* [PATCH v3 01/14] ARM: Add page table and page defines needed by KVM
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 02/14] ARM: Section based HYP idmap Christoffer Dall
` (12 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
KVM uses the stage-2 page tables and the Hyp page table format,
so we define the fields and page protection flags needed by KVM.
The nomenclature is this:
- page_hyp: PL2 code/data mappings
- page_hyp_device: PL2 device mappings (vgic access)
- page_s2: Stage-2 code/data page mappings
- page_s2_device: Stage-2 device mappings (vgic access)
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/pgtable-3level.h | 18 ++++++++++++++++++
arch/arm/include/asm/pgtable.h | 7 +++++++
arch/arm/mm/mmu.c | 25 +++++++++++++++++++++++++
3 files changed, 50 insertions(+)
diff --git a/arch/arm/include/asm/pgtable-3level.h b/arch/arm/include/asm/pgtable-3level.h
index b249035..eaba5a4 100644
--- a/arch/arm/include/asm/pgtable-3level.h
+++ b/arch/arm/include/asm/pgtable-3level.h
@@ -102,11 +102,29 @@
*/
#define L_PGD_SWAPPER (_AT(pgdval_t, 1) << 55) /* swapper_pg_dir entry */
+/*
+ * 2nd stage PTE definitions for LPAE.
+ */
+#define L_PTE_S2_MT_UNCACHED (_AT(pteval_t, 0x5) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_MT_WRITETHROUGH (_AT(pteval_t, 0xa) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_MT_WRITEBACK (_AT(pteval_t, 0xf) << 2) /* MemAttr[3:0] */
+#define L_PTE_S2_RDONLY (_AT(pteval_t, 1) << 6) /* HAP[1] */
+#define L_PTE_S2_RDWR (_AT(pteval_t, 2) << 6) /* HAP[2:1] */
+
+/*
+ * Hyp-mode PL2 PTE definitions for LPAE.
+ */
+#define L_PTE_HYP L_PTE_USER
+
#ifndef __ASSEMBLY__
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!(pud_val(pud) & 2))
#define pud_present(pud) (pud_val(pud))
+#define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_TABLE)
+#define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \
+ PMD_TYPE_SECT)
#define pud_clear(pudp) \
do { \
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index 08c1231..dfb3918 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -70,6 +70,9 @@ extern void __pgd_error(const char *file, int line, pgd_t);
extern pgprot_t pgprot_user;
extern pgprot_t pgprot_kernel;
+extern pgprot_t pgprot_hyp_device;
+extern pgprot_t pgprot_s2;
+extern pgprot_t pgprot_s2_device;
#define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
@@ -82,6 +85,10 @@ extern pgprot_t pgprot_kernel;
#define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
#define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
#define PAGE_KERNEL_EXEC pgprot_kernel
+#define PAGE_HYP _MOD_PROT(pgprot_kernel, L_PTE_HYP)
+#define PAGE_HYP_DEVICE _MOD_PROT(pgprot_hyp_device, L_PTE_HYP)
+#define PAGE_S2 _MOD_PROT(pgprot_s2, L_PTE_S2_RDONLY)
+#define PAGE_S2_DEVICE _MOD_PROT(pgprot_s2_device, L_PTE_USER | L_PTE_S2_RDONLY)
#define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN)
#define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 941dfb9..087d949 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -57,43 +57,61 @@ static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
static unsigned int ecc_mask __initdata = 0;
pgprot_t pgprot_user;
pgprot_t pgprot_kernel;
+pgprot_t pgprot_hyp_device;
+pgprot_t pgprot_s2;
+pgprot_t pgprot_s2_device;
EXPORT_SYMBOL(pgprot_user);
EXPORT_SYMBOL(pgprot_kernel);
+EXPORT_SYMBOL(pgprot_hyp_device);
+EXPORT_SYMBOL(pgprot_s2);
+EXPORT_SYMBOL(pgprot_s2_device);
struct cachepolicy {
const char policy[16];
unsigned int cr_mask;
pmdval_t pmd;
pteval_t pte;
+ pteval_t pte_s2;
};
+#ifdef CONFIG_ARM_LPAE
+#define s2_policy(policy) policy
+#else
+#define s2_policy(policy) 0
+#endif
+
static struct cachepolicy cache_policies[] __initdata = {
{
.policy = "uncached",
.cr_mask = CR_W|CR_C,
.pmd = PMD_SECT_UNCACHED,
.pte = L_PTE_MT_UNCACHED,
+ .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
}, {
.policy = "buffered",
.cr_mask = CR_C,
.pmd = PMD_SECT_BUFFERED,
.pte = L_PTE_MT_BUFFERABLE,
+ .pte_s2 = s2_policy(L_PTE_S2_MT_UNCACHED),
}, {
.policy = "writethrough",
.cr_mask = 0,
.pmd = PMD_SECT_WT,
.pte = L_PTE_MT_WRITETHROUGH,
+ .pte_s2 = s2_policy(L_PTE_S2_MT_WRITETHROUGH),
}, {
.policy = "writeback",
.cr_mask = 0,
.pmd = PMD_SECT_WB,
.pte = L_PTE_MT_WRITEBACK,
+ .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
}, {
.policy = "writealloc",
.cr_mask = 0,
.pmd = PMD_SECT_WBWA,
.pte = L_PTE_MT_WRITEALLOC,
+ .pte_s2 = s2_policy(L_PTE_S2_MT_WRITEBACK),
}
};
@@ -310,6 +328,7 @@ static void __init build_mem_type_table(void)
struct cachepolicy *cp;
unsigned int cr = get_cr();
pteval_t user_pgprot, kern_pgprot, vecs_pgprot;
+ pteval_t hyp_device_pgprot, s2_pgprot, s2_device_pgprot;
int cpu_arch = cpu_architecture();
int i;
@@ -421,6 +440,8 @@ static void __init build_mem_type_table(void)
*/
cp = &cache_policies[cachepolicy];
vecs_pgprot = kern_pgprot = user_pgprot = cp->pte;
+ s2_pgprot = cp->pte_s2;
+ hyp_device_pgprot = s2_device_pgprot = mem_types[MT_DEVICE].prot_pte;
/*
* ARMv6 and above have extended page tables.
@@ -444,6 +465,7 @@ static void __init build_mem_type_table(void)
user_pgprot |= L_PTE_SHARED;
kern_pgprot |= L_PTE_SHARED;
vecs_pgprot |= L_PTE_SHARED;
+ s2_pgprot |= L_PTE_SHARED;
mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S;
mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED;
mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S;
@@ -498,6 +520,9 @@ static void __init build_mem_type_table(void)
pgprot_user = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | user_pgprot);
pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
L_PTE_DIRTY | kern_pgprot);
+ pgprot_s2 = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | s2_pgprot);
+ pgprot_s2_device = __pgprot(s2_device_pgprot);
+ pgprot_hyp_device = __pgprot(hyp_device_pgprot);
mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 02/14] ARM: Section based HYP idmap
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 01/14] ARM: Add page table and page defines needed by KVM Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 03/14] ARM: Factor out cpuid implementor and part number Christoffer Dall
` (11 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
Add a method (hyp_idmap_setup) to populate a hyp pgd with an
identity mapping of the code contained in the .hyp.idmap.text
section.
Offer a method to drop the this identity mapping through
hyp_idmap_teardown.
Make all the above depend on CONFIG_ARM_VIRT_EXT and CONFIG_ARM_LPAE.
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/idmap.h | 5 ++
arch/arm/include/asm/pgtable-3level-hwdef.h | 1
arch/arm/kernel/vmlinux.lds.S | 6 ++
arch/arm/mm/idmap.c | 74 +++++++++++++++++++++++----
4 files changed, 73 insertions(+), 13 deletions(-)
diff --git a/arch/arm/include/asm/idmap.h b/arch/arm/include/asm/idmap.h
index bf863ed..36708ba 100644
--- a/arch/arm/include/asm/idmap.h
+++ b/arch/arm/include/asm/idmap.h
@@ -11,4 +11,9 @@ extern pgd_t *idmap_pgd;
void setup_mm_for_reboot(void);
+#ifdef CONFIG_ARM_VIRT_EXT
+void hyp_idmap_teardown(pgd_t *hyp_pgd);
+void hyp_idmap_setup(pgd_t *hyp_pgd);
+#endif
+
#endif /* __ASM_IDMAP_H */
diff --git a/arch/arm/include/asm/pgtable-3level-hwdef.h b/arch/arm/include/asm/pgtable-3level-hwdef.h
index d795282..a2d404e 100644
--- a/arch/arm/include/asm/pgtable-3level-hwdef.h
+++ b/arch/arm/include/asm/pgtable-3level-hwdef.h
@@ -44,6 +44,7 @@
#define PMD_SECT_XN (_AT(pmdval_t, 1) << 54)
#define PMD_SECT_AP_WRITE (_AT(pmdval_t, 0))
#define PMD_SECT_AP_READ (_AT(pmdval_t, 0))
+#define PMD_SECT_AP1 (_AT(pmdval_t, 1) << 6)
#define PMD_SECT_TEX(x) (_AT(pmdval_t, 0))
/*
diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S
index 36ff15b..12fd2eb 100644
--- a/arch/arm/kernel/vmlinux.lds.S
+++ b/arch/arm/kernel/vmlinux.lds.S
@@ -19,7 +19,11 @@
ALIGN_FUNCTION(); \
VMLINUX_SYMBOL(__idmap_text_start) = .; \
*(.idmap.text) \
- VMLINUX_SYMBOL(__idmap_text_end) = .;
+ VMLINUX_SYMBOL(__idmap_text_end) = .; \
+ ALIGN_FUNCTION(); \
+ VMLINUX_SYMBOL(__hyp_idmap_text_start) = .; \
+ *(.hyp.idmap.text) \
+ VMLINUX_SYMBOL(__hyp_idmap_text_end) = .;
#ifdef CONFIG_HOTPLUG_CPU
#define ARM_CPU_DISCARD(x)
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index ab88ed4..ea7430e 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -1,4 +1,6 @@
+#include <linux/module.h>
#include <linux/kernel.h>
+#include <linux/slab.h>
#include <asm/cputype.h>
#include <asm/idmap.h>
@@ -6,6 +8,7 @@
#include <asm/pgtable.h>
#include <asm/sections.h>
#include <asm/system_info.h>
+#include <asm/virt.h>
pgd_t *idmap_pgd;
@@ -59,11 +62,20 @@ static void idmap_add_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
} while (pud++, addr = next, addr != end);
}
-static void identity_mapping_add(pgd_t *pgd, unsigned long addr, unsigned long end)
+static void identity_mapping_add(pgd_t *pgd, const char *text_start,
+ const char *text_end, unsigned long prot)
{
- unsigned long prot, next;
+ unsigned long addr, end;
+ unsigned long next;
+
+ addr = virt_to_phys(text_start);
+ end = virt_to_phys(text_end);
+
+ pr_info("Setting up static %sidentity map for 0x%llx - 0x%llx\n",
+ prot ? "HYP " : "",
+ (long long)addr, (long long)end);
+ prot |= PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;
- prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;
if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())
prot |= PMD_BIT4;
@@ -78,24 +90,62 @@ extern char __idmap_text_start[], __idmap_text_end[];
static int __init init_static_idmap(void)
{
- phys_addr_t idmap_start, idmap_end;
-
idmap_pgd = pgd_alloc(&init_mm);
if (!idmap_pgd)
return -ENOMEM;
- /* Add an identity mapping for the physical address of the section. */
- idmap_start = virt_to_phys((void *)__idmap_text_start);
- idmap_end = virt_to_phys((void *)__idmap_text_end);
-
- pr_info("Setting up static identity map for 0x%llx - 0x%llx\n",
- (long long)idmap_start, (long long)idmap_end);
- identity_mapping_add(idmap_pgd, idmap_start, idmap_end);
+ identity_mapping_add(idmap_pgd, __idmap_text_start,
+ __idmap_text_end, 0);
return 0;
}
early_initcall(init_static_idmap);
+#if defined(CONFIG_ARM_VIRT_EXT) && defined(CONFIG_ARM_LPAE)
+static void hyp_idmap_del_pmd(pgd_t *pgd, unsigned long addr)
+{
+ pud_t *pud;
+ pmd_t *pmd;
+
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
+ pud_clear(pud);
+ clean_pmd_entry(pmd);
+ pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
+}
+
+extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
+
+/*
+ * This version actually frees the underlying pmds for all pgds in range and
+ * clear the pgds themselves afterwards.
+ */
+void hyp_idmap_teardown(pgd_t *hyp_pgd)
+{
+ unsigned long addr, end;
+ unsigned long next;
+ pgd_t *pgd = hyp_pgd;
+
+ addr = virt_to_phys(__hyp_idmap_text_start);
+ end = virt_to_phys(__hyp_idmap_text_end);
+
+ pgd += pgd_index(addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (!pgd_none_or_clear_bad(pgd))
+ hyp_idmap_del_pmd(pgd, addr);
+ } while (pgd++, addr = next, addr < end);
+}
+EXPORT_SYMBOL_GPL(hyp_idmap_teardown);
+
+void hyp_idmap_setup(pgd_t *hyp_pgd)
+{
+ identity_mapping_add(hyp_pgd, __hyp_idmap_text_start,
+ __hyp_idmap_text_end, PMD_SECT_AP1);
+}
+EXPORT_SYMBOL_GPL(hyp_idmap_setup);
+#endif
+
/*
* In order to soft-boot, we need to switch to a 1:1 mapping for the
* cpu_reset functions. This will then ensure that we have predictable
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 03/14] ARM: Factor out cpuid implementor and part number
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 01/14] ARM: Add page table and page defines needed by KVM Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 02/14] ARM: Section based HYP idmap Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 04/14] KVM: ARM: Initial skeleton to compile KVM support Christoffer Dall
` (10 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
Decoding the implementor and part number of the CPU id in the CPU ID
register is needed by KVM, so we factor it out to share the code.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/cputype.h | 26 ++++++++++++++++++++++++++
arch/arm/kernel/perf_event_cpu.c | 30 +++++++++++++++---------------
2 files changed, 41 insertions(+), 15 deletions(-)
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index cb47d28..306fb2c 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -51,6 +51,22 @@ extern unsigned int processor_id;
#define read_cpuid_ext(reg) 0
#endif
+#define IMPLEMENTOR_ARM 0x41
+#define IMPLEMENTOR_INTEL 0x69
+
+#define PART_NUMBER_ARM1136 0xB360
+#define PART_NUMBER_ARM1156 0xB560
+#define PART_NUMBER_ARM1176 0xB760
+#define PART_NUMBER_ARM11MPCORE 0xB020
+#define PART_NUMBER_CORTEX_A8 0xC080
+#define PART_NUMBER_CORTEX_A9 0xC090
+#define PART_NUMBER_CORTEX_A5 0xC050
+#define PART_NUMBER_CORTEX_A15 0xC0F0
+#define PART_NUMBER_CORTEX_A7 0xC070
+
+#define PART_NUMBER_XSCALE1 0x1
+#define PART_NUMBER_XSCALE2 0x2
+
/*
* The CPU ID never changes at run time, so we might as well tell the
* compiler that it's constant. Use this function to read the CPU ID
@@ -61,6 +77,16 @@ static inline unsigned int __attribute_const__ read_cpuid_id(void)
return read_cpuid(CPUID_ID);
}
+static inline unsigned int __attribute_const__ read_cpuid_implementor(void)
+{
+ return (read_cpuid_id() & 0xFF000000) >> 24;
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_part_number(void)
+{
+ return (read_cpuid_id() & 0xFFF0);
+}
+
static inline unsigned int __attribute_const__ read_cpuid_cachetype(void)
{
return read_cpuid(CPUID_CACHETYPE);
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 8d7d8d4..ff18566 100644
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -200,46 +200,46 @@ static struct arm_pmu *__devinit probe_current_pmu(void)
struct arm_pmu *pmu = NULL;
int cpu = get_cpu();
unsigned long cpuid = read_cpuid_id();
- unsigned long implementor = (cpuid & 0xFF000000) >> 24;
- unsigned long part_number = (cpuid & 0xFFF0);
+ unsigned long implementor = read_cpuid_implementor();
+ unsigned long part_number = read_cpuid_part_number();
pr_info("probing PMU on CPU %d\n", cpu);
/* ARM Ltd CPUs. */
- if (0x41 == implementor) {
+ if (implementor == IMPLEMENTOR_ARM) {
switch (part_number) {
- case 0xB360: /* ARM1136 */
- case 0xB560: /* ARM1156 */
- case 0xB760: /* ARM1176 */
+ case PART_NUMBER_ARM1136:
+ case PART_NUMBER_ARM1156:
+ case PART_NUMBER_ARM1176:
pmu = armv6pmu_init();
break;
- case 0xB020: /* ARM11mpcore */
+ case PART_NUMBER_ARM11MPCORE:
pmu = armv6mpcore_pmu_init();
break;
- case 0xC080: /* Cortex-A8 */
+ case PART_NUMBER_CORTEX_A8:
pmu = armv7_a8_pmu_init();
break;
- case 0xC090: /* Cortex-A9 */
+ case PART_NUMBER_CORTEX_A9:
pmu = armv7_a9_pmu_init();
break;
- case 0xC050: /* Cortex-A5 */
+ case PART_NUMBER_CORTEX_A5:
pmu = armv7_a5_pmu_init();
break;
- case 0xC0F0: /* Cortex-A15 */
+ case PART_NUMBER_CORTEX_A15:
pmu = armv7_a15_pmu_init();
break;
- case 0xC070: /* Cortex-A7 */
+ case PART_NUMBER_CORTEX_A7:
pmu = armv7_a7_pmu_init();
break;
}
/* Intel CPUs [xscale]. */
- } else if (0x69 == implementor) {
+ } else if (implementor == IMPLEMENTOR_INTEL) {
part_number = (cpuid >> 13) & 0x7;
switch (part_number) {
- case 1:
+ case PART_NUMBER_XSCALE1:
pmu = xscale1pmu_init();
break;
- case 2:
+ case PART_NUMBER_XSCALE2:
pmu = xscale2pmu_init();
break;
}
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 04/14] KVM: ARM: Initial skeleton to compile KVM support
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (2 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 03/14] ARM: Factor out cpuid implementor and part number Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 05/14] KVM: ARM: Hypervisor inititalization Christoffer Dall
` (9 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
Targets KVM support for Cortex A-15 processors.
Contains all the framework components, make files, header files, some
tracing functionality, and basic user space API.
Only supported core is Cortex-A15 for now.
Most functionality is in arch/arm/kvm/* or arch/arm/include/asm/kvm_*.h.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
Documentation/virtual/kvm/api.txt | 58 ++++++
arch/arm/Kconfig | 2
arch/arm/Makefile | 1
arch/arm/include/asm/kvm_arm.h | 24 +++
arch/arm/include/asm/kvm_asm.h | 58 ++++++
arch/arm/include/asm/kvm_coproc.h | 24 +++
arch/arm/include/asm/kvm_emulate.h | 50 +++++
arch/arm/include/asm/kvm_host.h | 120 +++++++++++++
arch/arm/include/uapi/asm/kvm.h | 83 +++++++++
arch/arm/kvm/Kconfig | 44 +++++
arch/arm/kvm/Makefile | 21 ++
arch/arm/kvm/arm.c | 343 ++++++++++++++++++++++++++++++++++++
arch/arm/kvm/coproc.c | 22 ++
arch/arm/kvm/emulate.c | 151 ++++++++++++++++
arch/arm/kvm/guest.c | 221 +++++++++++++++++++++++
arch/arm/kvm/init.S | 19 ++
arch/arm/kvm/interrupts.S | 19 ++
arch/arm/kvm/mmu.c | 17 ++
arch/arm/kvm/reset.c | 74 ++++++++
arch/arm/kvm/trace.h | 52 +++++
include/uapi/linux/kvm.h | 7 +
21 files changed, 1406 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/include/asm/kvm_arm.h
create mode 100644 arch/arm/include/asm/kvm_asm.h
create mode 100644 arch/arm/include/asm/kvm_coproc.h
create mode 100644 arch/arm/include/asm/kvm_emulate.h
create mode 100644 arch/arm/include/asm/kvm_host.h
create mode 100644 arch/arm/include/uapi/asm/kvm.h
create mode 100644 arch/arm/kvm/Kconfig
create mode 100644 arch/arm/kvm/Makefile
create mode 100644 arch/arm/kvm/arm.c
create mode 100644 arch/arm/kvm/coproc.c
create mode 100644 arch/arm/kvm/emulate.c
create mode 100644 arch/arm/kvm/guest.c
create mode 100644 arch/arm/kvm/init.S
create mode 100644 arch/arm/kvm/interrupts.S
create mode 100644 arch/arm/kvm/mmu.c
create mode 100644 arch/arm/kvm/reset.c
create mode 100644 arch/arm/kvm/trace.h
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 4258180..b56bbd5 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -293,7 +293,7 @@ kvm_run' (see below).
4.11 KVM_GET_REGS
Capability: basic
-Architectures: all
+Architectures: all except ARM
Type: vcpu ioctl
Parameters: struct kvm_regs (out)
Returns: 0 on success, -1 on error
@@ -314,7 +314,7 @@ struct kvm_regs {
4.12 KVM_SET_REGS
Capability: basic
-Architectures: all
+Architectures: all except ARM
Type: vcpu ioctl
Parameters: struct kvm_regs (in)
Returns: 0 on success, -1 on error
@@ -600,7 +600,7 @@ struct kvm_fpu {
4.24 KVM_CREATE_IRQCHIP
Capability: KVM_CAP_IRQCHIP
-Architectures: x86, ia64
+Architectures: x86, ia64, ARM
Type: vm ioctl
Parameters: none
Returns: 0 on success, -1 on error
@@ -608,7 +608,8 @@ Returns: 0 on success, -1 on error
Creates an interrupt controller model in the kernel. On x86, creates a virtual
ioapic, a virtual PIC (two PICs, nested), and sets up future vcpus to have a
local APIC. IRQ routing for GSIs 0-15 is set to both PIC and IOAPIC; GSI 16-23
-only go to the IOAPIC. On ia64, a IOSAPIC is created.
+only go to the IOAPIC. On ia64, a IOSAPIC is created. On ARM, a GIC is
+created.
4.25 KVM_IRQ_LINE
@@ -1774,6 +1775,14 @@ registers, find a list below:
PPC | KVM_REG_PPC_VPA_SLB | 128
PPC | KVM_REG_PPC_VPA_DTL | 128
+ARM registers are mapped using the lower 32 bits. The upper 16 of that
+is the register group type, or coprocessor number:
+
+ARM core registers have the following id bit patterns:
+ 0x4002 0000 0010 <index into the kvm_regs struct:16>
+
+
+
4.69 KVM_GET_ONE_REG
Capability: KVM_CAP_ONE_REG
@@ -1791,6 +1800,7 @@ The list of registers accessible using this interface is identical to the
list in 4.68.
+
4.70 KVM_KVMCLOCK_CTRL
Capability: KVM_CAP_KVMCLOCK_CTRL
@@ -2072,6 +2082,46 @@ KVM_S390_INT_EXTERNAL_CALL (vcpu) - sigp external call; source cpu in parm
Note that the vcpu ioctl is asynchronous to vcpu execution.
+4.77 KVM_ARM_VCPU_INIT
+
+Capability: basic
+Architectures: arm
+Type: vcpu ioctl
+Parameters: struct struct kvm_vcpu_init (in)
+Returns: 0 on success; -1 on error
+Errors:
+ ?EINVAL: ???the target is unknown, or the combination of features is invalid.
+ ?ENOENT: ???a features bit specified is unknown.
+
+This tells KVM what type of CPU to present to the guest, and what
+optional features it should have. ?This will cause a reset of the cpu
+registers to their initial values. ?If this is not called, KVM_RUN will
+return ENOEXEC for that vcpu.
+
+Note that because some registers reflect machine topology, all vcpus
+should be created before this ioctl is invoked.
+
+
+4.78 KVM_GET_REG_LIST
+
+Capability: basic
+Architectures: arm
+Type: vcpu ioctl
+Parameters: struct kvm_reg_list (in/out)
+Returns: 0 on success; -1 on error
+Errors:
+ ?E2BIG: ????the reg index list is too big to fit in the array specified by
+ ????????????the user (the number required will be written into n).
+
+struct kvm_reg_list {
+ __u64 n; /* number of registers in reg[] */
+ __u64 reg[0];
+};
+
+This ioctl returns the guest registers that are supported for the
+KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
+
+
5. The kvm_run structure
------------------------
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 73067ef..263d47a 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -2310,3 +2310,5 @@ source "security/Kconfig"
source "crypto/Kconfig"
source "lib/Kconfig"
+
+source "arch/arm/kvm/Kconfig"
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index f023e3a..361a683 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -256,6 +256,7 @@ core-$(CONFIG_XEN) += arch/arm/xen/
core-y += arch/arm/kernel/ arch/arm/mm/ arch/arm/common/
core-y += arch/arm/net/
core-y += arch/arm/crypto/
+core-y += arch/arm/kvm/
core-y += $(machdirs) $(platdirs)
drivers-$(CONFIG_OPROFILE) += arch/arm/oprofile/
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
new file mode 100644
index 0000000..c196a22
--- /dev/null
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_ARM_H__
+#define __ARM_KVM_ARM_H__
+
+#include <asm/types.h>
+
+#endif /* __ARM_KVM_ARM_H__ */
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
new file mode 100644
index 0000000..48ddf99
--- /dev/null
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_ASM_H__
+#define __ARM_KVM_ASM_H__
+
+/* 0 is reserved as an invalid value. */
+#define c0_MPIDR 1 /* MultiProcessor ID Register */
+#define c0_CSSELR 2 /* Cache Size Selection Register */
+#define c1_SCTLR 3 /* System Control Register */
+#define c1_ACTLR 4 /* Auxilliary Control Register */
+#define c1_CPACR 5 /* Coprocessor Access Control */
+#define c2_TTBR0 6 /* Translation Table Base Register 0 */
+#define c2_TTBR0_high 7 /* TTBR0 top 32 bits */
+#define c2_TTBR1 8 /* Translation Table Base Register 1 */
+#define c2_TTBR1_high 9 /* TTBR1 top 32 bits */
+#define c2_TTBCR 10 /* Translation Table Base Control R. */
+#define c3_DACR 11 /* Domain Access Control Register */
+#define c5_DFSR 12 /* Data Fault Status Register */
+#define c5_IFSR 13 /* Instruction Fault Status Register */
+#define c5_ADFSR 14 /* Auxilary Data Fault Status R */
+#define c5_AIFSR 15 /* Auxilary Instrunction Fault Status R */
+#define c6_DFAR 16 /* Data Fault Address Register */
+#define c6_IFAR 17 /* Instruction Fault Address Register */
+#define c9_L2CTLR 18 /* Cortex A15 L2 Control Register */
+#define c10_PRRR 19 /* Primary Region Remap Register */
+#define c10_NMRR 20 /* Normal Memory Remap Register */
+#define c12_VBAR 21 /* Vector Base Address Register */
+#define c13_CID 22 /* Context ID Register */
+#define c13_TID_URW 23 /* Thread ID, User R/W */
+#define c13_TID_URO 24 /* Thread ID, User R/O */
+#define c13_TID_PRIV 25 /* Thread ID, Priveleged */
+#define NR_CP15_REGS 26 /* Number of regs (incl. invalid) */
+
+#define ARM_EXCEPTION_RESET 0
+#define ARM_EXCEPTION_UNDEFINED 1
+#define ARM_EXCEPTION_SOFTWARE 2
+#define ARM_EXCEPTION_PREF_ABORT 3
+#define ARM_EXCEPTION_DATA_ABORT 4
+#define ARM_EXCEPTION_IRQ 5
+#define ARM_EXCEPTION_FIQ 6
+
+#endif /* __ARM_KVM_ASM_H__ */
diff --git a/arch/arm/include/asm/kvm_coproc.h b/arch/arm/include/asm/kvm_coproc.h
new file mode 100644
index 0000000..b6d023d
--- /dev/null
+++ b/arch/arm/include/asm/kvm_coproc.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2012 Rusty Russell IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_COPROC_H__
+#define __ARM_KVM_COPROC_H__
+#include <linux/kvm_host.h>
+
+void kvm_reset_coprocs(struct kvm_vcpu *vcpu);
+
+#endif /* __ARM_KVM_COPROC_H__ */
diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
new file mode 100644
index 0000000..7d3e904
--- /dev/null
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_EMULATE_H__
+#define __ARM_KVM_EMULATE_H__
+
+#include <linux/kvm_host.h>
+#include <asm/kvm_asm.h>
+
+u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num);
+u32 *vcpu_spsr(struct kvm_vcpu *vcpu);
+
+static inline u32 *vcpu_pc(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.regs.pc;
+}
+
+static inline u32 *vcpu_cpsr(struct kvm_vcpu *vcpu)
+{
+ return &vcpu->arch.regs.cpsr;
+}
+
+static inline bool mode_has_spsr(struct kvm_vcpu *vcpu)
+{
+ unsigned long cpsr_mode = vcpu->arch.regs.cpsr & MODE_MASK;
+ return (cpsr_mode > USR_MODE && cpsr_mode < SYSTEM_MODE);
+}
+
+static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu)
+{
+ unsigned long cpsr_mode = vcpu->arch.regs.cpsr & MODE_MASK;
+ return cpsr_mode > USR_MODE;;
+}
+
+#endif /* __ARM_KVM_EMULATE_H__ */
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
new file mode 100644
index 0000000..15d4c0b
--- /dev/null
+++ b/arch/arm/include/asm/kvm_host.h
@@ -0,0 +1,120 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_HOST_H__
+#define __ARM_KVM_HOST_H__
+
+#include <asm/kvm.h>
+#include <asm/kvm_asm.h>
+
+#define KVM_MAX_VCPUS NR_CPUS
+#define KVM_MEMORY_SLOTS 32
+#define KVM_PRIVATE_MEM_SLOTS 4
+#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
+
+#define KVM_VCPU_MAX_FEATURES 0
+
+/* We don't currently support large pages. */
+#define KVM_HPAGE_GFN_SHIFT(x) 0
+#define KVM_NR_PAGE_SIZES 1
+#define KVM_PAGES_PER_HPAGE(x) (1UL<<31)
+
+struct kvm_vcpu;
+u32 *kvm_vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num, u32 mode);
+int kvm_target_cpu(void);
+int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
+void kvm_reset_coprocs(struct kvm_vcpu *vcpu);
+
+struct kvm_arch {
+ /* VTTBR value associated with below pgd and vmid */
+ u64 vttbr;
+
+ /*
+ * Anything that is not used directly from assembly code goes
+ * here.
+ */
+
+ /* The VMID generation used for the virt. memory system */
+ u64 vmid_gen;
+ u32 vmid;
+
+ /* Stage-2 page table */
+ pgd_t *pgd;
+};
+
+#define KVM_NR_MEM_OBJS 40
+
+/*
+ * We don't want allocation failures within the mmu code, so we preallocate
+ * enough memory for a single page fault in a cache.
+ */
+struct kvm_mmu_memory_cache {
+ int nobjs;
+ void *objects[KVM_NR_MEM_OBJS];
+};
+
+struct kvm_vcpu_arch {
+ struct kvm_regs regs;
+
+ int target; /* Processor target */
+ DECLARE_BITMAP(features, KVM_VCPU_MAX_FEATURES);
+
+ /* System control coprocessor (cp15) */
+ u32 cp15[NR_CP15_REGS];
+
+ /* The CPU type we expose to the VM */
+ u32 midr;
+
+ /* Exception Information */
+ u32 hsr; /* Hyp Syndrom Register */
+ u32 hxfar; /* Hyp Data/Inst Fault Address Register */
+ u32 hpfar; /* Hyp IPA Fault Address Register */
+
+ /* IO related fields */
+ struct {
+ bool sign_extend; /* for byte/halfword loads */
+ u32 rd;
+ } mmio;
+
+ /* Interrupt related fields */
+ u32 irq_lines; /* IRQ and FIQ levels */
+
+ /* Hyp exception information */
+ u32 hyp_pc; /* PC when exception was taken from Hyp mode */
+
+ /* Cache some mmu pages needed inside spinlock regions */
+ struct kvm_mmu_memory_cache mmu_page_cache;
+};
+
+struct kvm_vm_stat {
+ u32 remote_tlb_flush;
+};
+
+struct kvm_vcpu_stat {
+ u32 halt_wakeup;
+};
+
+struct kvm_vcpu_init;
+int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
+ const struct kvm_vcpu_init *init);
+unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
+int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
+struct kvm_one_reg;
+int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+#endif /* __ARM_KVM_HOST_H__ */
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
new file mode 100644
index 0000000..bfc2123
--- /dev/null
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_H__
+#define __ARM_KVM_H__
+
+#include <asm/types.h>
+
+#define __KVM_HAVE_GUEST_DEBUG
+
+#define KVM_REG_SIZE(id) \
+ (1U << (((id) & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT))
+
+struct kvm_regs {
+ __u32 usr_regs[15]; /* R0_usr - R14_usr */
+ __u32 svc_regs[3]; /* SP_svc, LR_svc, SPSR_svc */
+ __u32 abt_regs[3]; /* SP_abt, LR_abt, SPSR_abt */
+ __u32 und_regs[3]; /* SP_und, LR_und, SPSR_und */
+ __u32 irq_regs[3]; /* SP_irq, LR_irq, SPSR_irq */
+ __u32 fiq_regs[8]; /* R8_fiq - R14_fiq, SPSR_fiq */
+ __u32 pc; /* The program counter (r15) */
+ __u32 cpsr; /* The guest CPSR */
+};
+
+/* Supported Processor Types */
+#define KVM_ARM_TARGET_CORTEX_A15 0
+#define KVM_ARM_NUM_TARGETS 1
+
+struct kvm_vcpu_init {
+ __u32 target;
+ __u32 features[7];
+};
+
+struct kvm_sregs {
+};
+
+struct kvm_fpu {
+};
+
+struct kvm_guest_debug_arch {
+};
+
+struct kvm_debug_exit_arch {
+};
+
+struct kvm_sync_regs {
+};
+
+struct kvm_arch_memory_slot {
+};
+
+/* If you need to interpret the index values, here is the key: */
+#define KVM_REG_ARM_COPROC_MASK 0x000000000FFF0000
+#define KVM_REG_ARM_COPROC_SHIFT 16
+#define KVM_REG_ARM_32_OPC2_MASK 0x0000000000000007
+#define KVM_REG_ARM_32_OPC2_SHIFT 0
+#define KVM_REG_ARM_OPC1_MASK 0x0000000000000078
+#define KVM_REG_ARM_OPC1_SHIFT 3
+#define KVM_REG_ARM_CRM_MASK 0x0000000000000780
+#define KVM_REG_ARM_CRM_SHIFT 7
+#define KVM_REG_ARM_32_CRN_MASK 0x0000000000007800
+#define KVM_REG_ARM_32_CRN_SHIFT 11
+
+/* Normal registers are mapped as coprocessor 16. */
+#define KVM_REG_ARM_CORE (0x0010 << KVM_REG_ARM_COPROC_SHIFT)
+#define KVM_REG_ARM_CORE_REG(name) (offsetof(struct kvm_regs, name) / 4)
+
+#endif /* __ARM_KVM_H__ */
diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
new file mode 100644
index 0000000..a07ddcc
--- /dev/null
+++ b/arch/arm/kvm/Kconfig
@@ -0,0 +1,44 @@
+#
+# KVM configuration
+#
+
+source "virt/kvm/Kconfig"
+
+menuconfig VIRTUALIZATION
+ bool "Virtualization"
+ ---help---
+ Say Y here to get to see options for using your Linux host to run
+ other operating systems inside virtual machines (guests).
+ This option alone does not add any kernel code.
+
+ If you say N, all options in this submenu will be skipped and
+ disabled.
+
+if VIRTUALIZATION
+
+config KVM
+ bool "Kernel-based Virtual Machine (KVM) support"
+ select PREEMPT_NOTIFIERS
+ select ANON_INODES
+ select KVM_MMIO
+ depends on ARM_VIRT_EXT && ARM_LPAE
+ ---help---
+ Support hosting virtualized guest machines. You will also
+ need to select one or more of the processor modules below.
+
+ This module provides access to the hardware capabilities through
+ a character device node named /dev/kvm.
+
+ If unsure, say N.
+
+config KVM_ARM_HOST
+ bool "KVM host support for ARM cpus."
+ depends on KVM
+ depends on MMU
+ depends on CPU_V7 && ARM_VIRT_EXT
+ ---help---
+ Provides host support for ARM processors.
+
+source drivers/virtio/Kconfig
+
+endif # VIRTUALIZATION
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
new file mode 100644
index 0000000..7acf3ea
--- /dev/null
+++ b/arch/arm/kvm/Makefile
@@ -0,0 +1,21 @@
+#
+# Makefile for Kernel-based Virtual Machine module
+#
+
+plus_virt := $(call as-instr,.arch_extension virt,+virt)
+ifeq ($(plus_virt),+virt)
+ plus_virt_def := -DREQUIRES_VIRT=1
+endif
+
+ccflags-y += -Ivirt/kvm -Iarch/arm/kvm
+CFLAGS_arm.o := -I. $(plus_virt_def)
+CFLAGS_mmu.o := -I.
+
+AFLAGS_init.o := -Wa,-march=armv7-a$(plus_virt)
+AFLAGS_interrupts.o := -Wa,-march=armv7-a$(plus_virt)
+
+obj-$(CONFIG_KVM_ARM_HOST) += init.o interrupts.o
+
+obj-$(CONFIG_KVM_ARM_HOST) += $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o)
+
+obj-$(CONFIG_KVM_ARM_HOST) += arm.o guest.o mmu.o emulate.o reset.o coproc.o
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
new file mode 100644
index 0000000..ead5a4e
--- /dev/null
+++ b/arch/arm/kvm/arm.c
@@ -0,0 +1,343 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kvm_host.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/mman.h>
+#include <linux/sched.h>
+#include <trace/events/kvm.h>
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+#include <asm/unified.h>
+#include <asm/uaccess.h>
+#include <asm/ptrace.h>
+#include <asm/mman.h>
+#include <asm/cputype.h>
+
+#ifdef REQUIRES_VIRT
+__asm__(".arch_extension virt");
+#endif
+
+int kvm_arch_hardware_enable(void *garbage)
+{
+ return 0;
+}
+
+int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
+{
+ return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
+}
+
+void kvm_arch_hardware_disable(void *garbage)
+{
+}
+
+int kvm_arch_hardware_setup(void)
+{
+ return 0;
+}
+
+void kvm_arch_hardware_unsetup(void)
+{
+}
+
+void kvm_arch_check_processor_compat(void *rtn)
+{
+ *(int *)rtn = 0;
+}
+
+void kvm_arch_sync_events(struct kvm *kvm)
+{
+}
+
+int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
+{
+ if (type)
+ return -EINVAL;
+
+ return 0;
+}
+
+int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
+{
+ return VM_FAULT_SIGBUS;
+}
+
+void kvm_arch_free_memslot(struct kvm_memory_slot *free,
+ struct kvm_memory_slot *dont)
+{
+}
+
+int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
+{
+ return 0;
+}
+
+void kvm_arch_destroy_vm(struct kvm *kvm)
+{
+ int i;
+
+ for (i = 0; i < KVM_MAX_VCPUS; ++i) {
+ if (kvm->vcpus[i]) {
+ kvm_arch_vcpu_free(kvm->vcpus[i]);
+ kvm->vcpus[i] = NULL;
+ }
+ }
+}
+
+int kvm_dev_ioctl_check_extension(long ext)
+{
+ int r;
+ switch (ext) {
+ case KVM_CAP_USER_MEMORY:
+ case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
+ case KVM_CAP_ONE_REG:
+ r = 1;
+ break;
+ case KVM_CAP_COALESCED_MMIO:
+ r = KVM_COALESCED_MMIO_PAGE_OFFSET;
+ break;
+ default:
+ r = 0;
+ break;
+ }
+ return r;
+}
+
+long kvm_arch_dev_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_set_memory_region(struct kvm *kvm,
+ struct kvm_userspace_memory_region *mem,
+ struct kvm_memory_slot old,
+ int user_alloc)
+{
+ return 0;
+}
+
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+ struct kvm_memory_slot *memslot,
+ struct kvm_memory_slot old,
+ struct kvm_userspace_memory_region *mem,
+ int user_alloc)
+{
+ return 0;
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm,
+ struct kvm_userspace_memory_region *mem,
+ struct kvm_memory_slot old,
+ int user_alloc)
+{
+}
+
+void kvm_arch_flush_shadow_all(struct kvm *kvm)
+{
+}
+
+void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
+ struct kvm_memory_slot *slot)
+{
+}
+
+struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+{
+ int err;
+ struct kvm_vcpu *vcpu;
+
+ vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
+ if (!vcpu) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ err = kvm_vcpu_init(vcpu, kvm, id);
+ if (err)
+ goto free_vcpu;
+
+ return vcpu;
+free_vcpu:
+ kmem_cache_free(kvm_vcpu_cache, vcpu);
+out:
+ return ERR_PTR(err);
+}
+
+void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
+{
+}
+
+void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
+{
+ kvm_arch_vcpu_free(vcpu);
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+int __attribute_const__ kvm_target_cpu(void)
+{
+ unsigned long implementor = read_cpuid_implementor();
+ unsigned long part_number = read_cpuid_part_number();
+
+ if (implementor != IMPLEMENTOR_ARM)
+ return -EINVAL;
+
+ switch (part_number) {
+ case PART_NUMBER_CORTEX_A15:
+ return KVM_ARM_TARGET_CORTEX_A15;
+ default:
+ return -EINVAL;
+ }
+}
+
+int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
+{
+}
+
+void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+}
+
+void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
+{
+}
+
+int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
+ struct kvm_guest_debug *dbg)
+{
+ return -EINVAL;
+}
+
+
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+ struct kvm_mp_state *mp_state)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+ struct kvm_mp_state *mp_state)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
+{
+ return 0;
+}
+
+int kvm_arch_vcpu_in_guest_mode(struct kvm_vcpu *v)
+{
+ return 0;
+}
+
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ return -EINVAL;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ struct kvm_vcpu *vcpu = filp->private_data;
+ void __user *argp = (void __user *)arg;
+
+ switch (ioctl) {
+ case KVM_ARM_VCPU_INIT: {
+ struct kvm_vcpu_init init;
+
+ if (copy_from_user(&init, argp, sizeof init))
+ return -EFAULT;
+
+ return kvm_vcpu_set_target(vcpu, &init);
+
+ }
+ case KVM_SET_ONE_REG:
+ case KVM_GET_ONE_REG: {
+ struct kvm_one_reg reg;
+ if (copy_from_user(®, argp, sizeof(reg)))
+ return -EFAULT;
+ if (ioctl == KVM_SET_ONE_REG)
+ return kvm_arm_set_reg(vcpu, ®);
+ else
+ return kvm_arm_get_reg(vcpu, ®);
+ }
+ case KVM_GET_REG_LIST: {
+ struct kvm_reg_list __user *user_list = argp;
+ struct kvm_reg_list reg_list;
+ unsigned n;
+
+ if (copy_from_user(®_list, user_list, sizeof reg_list))
+ return -EFAULT;
+ n = reg_list.n;
+ reg_list.n = kvm_arm_num_regs(vcpu);
+ if (copy_to_user(user_list, ®_list, sizeof reg_list))
+ return -EFAULT;
+ if (n < reg_list.n)
+ return -E2BIG;
+ return kvm_arm_copy_reg_indices(vcpu, user_list->reg);
+ }
+ default:
+ return -EINVAL;
+ }
+}
+
+int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
+{
+ return -EINVAL;
+}
+
+long kvm_arch_vm_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_init(void *opaque)
+{
+ return 0;
+}
+
+/* NOP: Compiling as a module not supported */
+void kvm_arch_exit(void)
+{
+}
+
+static int arm_init(void)
+{
+ int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ return rc;
+}
+
+module_init(arm_init);
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
new file mode 100644
index 0000000..4b9dad8
--- /dev/null
+++ b/arch/arm/kvm/coproc.c
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <linux/kvm_host.h>
+
+void kvm_reset_coprocs(struct kvm_vcpu *vcpu)
+{
+}
diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
new file mode 100644
index 0000000..4e25b65
--- /dev/null
+++ b/arch/arm/kvm/emulate.c
@@ -0,0 +1,151 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <asm/kvm_emulate.h>
+
+#define VCPU_NR_MODES 6
+#define REG_OFFSET(_reg) \
+ (offsetof(struct kvm_regs, _reg) / sizeof(u32))
+
+#define USR_REG_OFFSET(_num) REG_OFFSET(usr_regs[_num])
+
+static const unsigned long vcpu_reg_offsets[VCPU_NR_MODES][15] = {
+ /* USR/SYS Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+ USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+ USR_REG_OFFSET(12), USR_REG_OFFSET(13), USR_REG_OFFSET(14),
+ },
+
+ /* FIQ Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7),
+ REG_OFFSET(fiq_regs[0]), /* r8 */
+ REG_OFFSET(fiq_regs[1]), /* r9 */
+ REG_OFFSET(fiq_regs[2]), /* r10 */
+ REG_OFFSET(fiq_regs[3]), /* r11 */
+ REG_OFFSET(fiq_regs[4]), /* r12 */
+ REG_OFFSET(fiq_regs[5]), /* r13 */
+ REG_OFFSET(fiq_regs[6]), /* r14 */
+ },
+
+ /* IRQ Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+ USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+ USR_REG_OFFSET(12),
+ REG_OFFSET(irq_regs[0]), /* r13 */
+ REG_OFFSET(irq_regs[1]), /* r14 */
+ },
+
+ /* SVC Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+ USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+ USR_REG_OFFSET(12),
+ REG_OFFSET(svc_regs[0]), /* r13 */
+ REG_OFFSET(svc_regs[1]), /* r14 */
+ },
+
+ /* ABT Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+ USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+ USR_REG_OFFSET(12),
+ REG_OFFSET(abt_regs[0]), /* r13 */
+ REG_OFFSET(abt_regs[1]), /* r14 */
+ },
+
+ /* UND Registers */
+ {
+ USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
+ USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
+ USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
+ USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
+ USR_REG_OFFSET(12),
+ REG_OFFSET(und_regs[0]), /* r13 */
+ REG_OFFSET(und_regs[1]), /* r14 */
+ },
+};
+
+/*
+ * Return a pointer to the register number valid in the current mode of
+ * the virtual CPU.
+ */
+u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
+{
+ u32 *reg_array = (u32 *)&vcpu->arch.regs;
+ u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+
+ BUG_ON(reg_num >= 15);
+
+ switch (mode) {
+ case USR_MODE...SVC_MODE:
+ mode &= ~MODE32_BIT; /* 0 ... 3 */
+ break;
+
+ case ABT_MODE:
+ mode = 4;
+ break;
+
+ case UND_MODE:
+ mode = 5;
+ break;
+
+ case SYSTEM_MODE:
+ mode = 0;
+ break;
+
+ default:
+ BUG();
+ }
+
+ return reg_array + vcpu_reg_offsets[mode][reg_num];
+}
+
+/*
+ * Return the SPSR for the current mode of the virtual CPU.
+ */
+u32 *vcpu_spsr(struct kvm_vcpu *vcpu)
+{
+ u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+ switch (mode) {
+ case SVC_MODE:
+ return &vcpu->arch.regs.svc_regs[2];
+ case ABT_MODE:
+ return &vcpu->arch.regs.abt_regs[2];
+ case UND_MODE:
+ return &vcpu->arch.regs.und_regs[2];
+ case IRQ_MODE:
+ return &vcpu->arch.regs.irq_regs[2];
+ case FIQ_MODE:
+ return &vcpu->arch.regs.fiq_regs[7];
+ default:
+ BUG();
+ }
+}
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
new file mode 100644
index 0000000..4fd0467
--- /dev/null
+++ b/arch/arm/kvm/guest.c
@@ -0,0 +1,221 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kvm_host.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+#include <asm/kvm.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_emulate.h>
+
+#define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
+#define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
+
+struct kvm_stats_debugfs_item debugfs_entries[] = {
+ { NULL }
+};
+
+int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+static u64 core_reg_offset_from_id(u64 id)
+{
+ return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
+}
+
+static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ u32 __user *uaddr = (u32 __user *)(long)reg->addr;
+ struct kvm_regs *regs = &vcpu->arch.regs;
+ u64 off;
+
+ if (KVM_REG_SIZE(reg->id) != 4)
+ return -ENOENT;
+
+ /* Our ID is an index into the kvm_regs struct. */
+ off = core_reg_offset_from_id(reg->id);
+ if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
+ return -ENOENT;
+
+ return put_user(((u32 *)regs)[off], uaddr);
+}
+
+static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ u32 __user *uaddr = (u32 __user *)(long)reg->addr;
+ struct kvm_regs *regs = &vcpu->arch.regs;
+ u64 off, val;
+
+ if (KVM_REG_SIZE(reg->id) != 4)
+ return -ENOENT;
+
+ /* Our ID is an index into the kvm_regs struct. */
+ off = core_reg_offset_from_id(reg->id);
+ if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
+ return -ENOENT;
+
+ if (get_user(val, uaddr) != 0)
+ return -EFAULT;
+
+ if (off == KVM_REG_ARM_CORE_REG(cpsr)) {
+ unsigned long mode = val & MODE_MASK;
+ switch (mode) {
+ case USR_MODE:
+ case FIQ_MODE:
+ case IRQ_MODE:
+ case SVC_MODE:
+ case ABT_MODE:
+ case UND_MODE:
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ ((u32 *)regs)[off] = val;
+ return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+ return -EINVAL;
+}
+
+static unsigned long num_core_regs(void)
+{
+ return sizeof(struct kvm_regs) / sizeof(u32);
+}
+
+/**
+ * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
+ *
+ * This is for all registers.
+ */
+unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
+{
+ return num_core_regs();
+}
+
+/**
+ * kvm_arm_copy_reg_indices - get indices of all registers.
+ *
+ * We do core registers right here, then we apppend coproc regs.
+ */
+int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+ unsigned int i;
+ const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
+
+ for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
+ if (put_user(core_reg | i, uindices))
+ return -EFAULT;
+ uindices++;
+ }
+
+ return 0;
+}
+
+int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ /* We currently use nothing arch-specific in upper 32 bits */
+ if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
+ return -EINVAL;
+
+ /* Register group 16 means we want a core register. */
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
+ return get_core_reg(vcpu, reg);
+
+ return -EINVAL;
+}
+
+int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ /* We currently use nothing arch-specific in upper 32 bits */
+ if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
+ return -EINVAL;
+
+ /* Register group 16 means we set a core register. */
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
+ return set_core_reg(vcpu, reg);
+
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+ struct kvm_sregs *sregs)
+{
+ return -EINVAL;
+}
+
+int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
+ const struct kvm_vcpu_init *init)
+{
+ unsigned int i;
+
+ /* We can only do a cortex A15 for now. */
+ if (init->target != kvm_target_cpu())
+ return -EINVAL;
+
+ vcpu->arch.target = init->target;
+ bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
+
+ /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
+ for (i = 0; i < sizeof(init->features)*8; i++) {
+ if (init->features[i / 32] & (1 << (i % 32))) {
+ if (i >= KVM_VCPU_MAX_FEATURES)
+ return -ENOENT;
+ set_bit(i, vcpu->arch.features);
+ }
+ }
+
+ /* Now we know what it is, we can reset it. */
+ return kvm_reset_vcpu(vcpu);
+}
+
+int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+ return -EINVAL;
+}
+
+int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+ struct kvm_translation *tr)
+{
+ return -EINVAL;
+}
diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S
new file mode 100644
index 0000000..1dc8926
--- /dev/null
+++ b/arch/arm/kvm/init.S
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <asm/asm-offsets.h>
+#include <asm/kvm_asm.h>
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
new file mode 100644
index 0000000..1dc8926
--- /dev/null
+++ b/arch/arm/kvm/interrupts.S
@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <asm/asm-offsets.h>
+#include <asm/kvm_asm.h>
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
new file mode 100644
index 0000000..10ed464
--- /dev/null
+++ b/arch/arm/kvm/mmu.c
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
diff --git a/arch/arm/kvm/reset.c b/arch/arm/kvm/reset.c
new file mode 100644
index 0000000..290a13d
--- /dev/null
+++ b/arch/arm/kvm/reset.c
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kvm_host.h>
+#include <linux/kvm.h>
+
+#include <asm/unified.h>
+#include <asm/ptrace.h>
+#include <asm/cputype.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_coproc.h>
+
+/******************************************************************************
+ * Cortex-A15 Reset Values
+ */
+
+static const int a15_max_cpu_idx = 3;
+
+static struct kvm_regs a15_regs_reset = {
+ .cpsr = SVC_MODE | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT,
+};
+
+
+/*******************************************************************************
+ * Exported reset function
+ */
+
+/**
+ * kvm_reset_vcpu - sets core registers and cp15 registers to reset value
+ * @vcpu: The VCPU pointer
+ *
+ * This function finds the right table above and sets the registers on the
+ * virtual CPU struct to their architectually defined reset values.
+ */
+int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
+{
+ struct kvm_regs *cpu_reset;
+
+ switch (vcpu->arch.target) {
+ case KVM_ARM_TARGET_CORTEX_A15:
+ if (vcpu->vcpu_id > a15_max_cpu_idx)
+ return -EINVAL;
+ cpu_reset = &a15_regs_reset;
+ vcpu->arch.midr = read_cpuid_id();
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ /* Reset core registers */
+ memcpy(&vcpu->arch.regs, cpu_reset, sizeof(vcpu->arch.regs));
+
+ /* Reset CP15 registers */
+ kvm_reset_coprocs(vcpu);
+
+ return 0;
+}
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
new file mode 100644
index 0000000..f8869c1
--- /dev/null
+++ b/arch/arm/kvm/trace.h
@@ -0,0 +1,52 @@
+#if !defined(_TRACE_KVM_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_KVM_H
+
+#include <linux/tracepoint.h>
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM kvm
+
+/*
+ * Tracepoints for entry/exit to guest
+ */
+TRACE_EVENT(kvm_entry,
+ TP_PROTO(unsigned long vcpu_pc),
+ TP_ARGS(vcpu_pc),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ ),
+
+ TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
+);
+
+TRACE_EVENT(kvm_exit,
+ TP_PROTO(unsigned long vcpu_pc),
+ TP_ARGS(vcpu_pc),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ ),
+
+ TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
+);
+
+
+
+#endif /* _TRACE_KVM_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH arch/arm/kvm
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 65ad5c6..ba9feed 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -759,6 +759,11 @@ struct kvm_dirty_tlb {
#define KVM_REG_SIZE_U512 0x0060000000000000ULL
#define KVM_REG_SIZE_U1024 0x0070000000000000ULL
+struct kvm_reg_list {
+ __u64 n; /* number of regs */
+ __u64 reg[0];
+};
+
struct kvm_one_reg {
__u64 id;
__u64 addr;
@@ -925,6 +930,8 @@ struct kvm_s390_ucas_mapping {
#define KVM_SET_ONE_REG _IOW(KVMIO, 0xac, struct kvm_one_reg)
/* VM is being stopped by host */
#define KVM_KVMCLOCK_CTRL _IO(KVMIO, 0xad)
+#define KVM_ARM_VCPU_INIT _IOW(KVMIO, 0xae, struct kvm_vcpu_init)
+#define KVM_GET_REG_LIST _IOWR(KVMIO, 0xb0, struct kvm_reg_list)
#define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0)
#define KVM_DEV_ASSIGN_PCI_2_3 (1 << 1)
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 05/14] KVM: ARM: Hypervisor inititalization
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (3 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 04/14] KVM: ARM: Initial skeleton to compile KVM support Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 06/14] KVM: ARM: Memory virtualization setup Christoffer Dall
` (8 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
Sets up KVM code to handle all exceptions taken to Hyp mode.
When the kernel is booted in Hyp mode, calling "hvc #0xff" with r0 pointing to
the new vectors, the HVBAR is changed to the the vector pointers. This allows
subsystems (like KVM here) to execute code in Hyp-mode with the MMU disabled.
We initialize other Hyp-mode registers and enables the MMU for Hyp-mode from
the id-mapped hyp initialization code. Afterwards, the HVBAR is changed to
point to KVM Hyp vectors used to catch guest faults and to switch to Hyp mode
to perform a world-switch into a KVM guest.
If the KVM module is unloaded we call "hvc #0xff" once more to disable the MMU
in Hyp mode again and install a vector handler to change the HVBAR for a
subsequent reload of KVM or another hypervisor.
Also provides memory mapping code to map required code pages, data structures,
and I/O regions accessed in Hyp mode at the same virtual address as the host
kernel virtual addresses, but which conforms to the architectural requirements
for translations in Hyp mode. This interface is added in arch/arm/kvm/arm_mmu.c
and comprises:
- create_hyp_mappings(from, to);
- create_hyp_io_mappings(from, to, phys_addr);
- free_hyp_pmds();
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 107 ++++++++++++++
arch/arm/include/asm/kvm_asm.h | 20 +++
arch/arm/include/asm/kvm_mmu.h | 39 +++++
arch/arm/include/asm/pgtable-3level-hwdef.h | 4 +
arch/arm/kvm/arm.c | 172 ++++++++++++++++++++++
arch/arm/kvm/init.S | 107 ++++++++++++++
arch/arm/kvm/interrupts.S | 48 ++++++
arch/arm/kvm/mmu.c | 210 +++++++++++++++++++++++++++
mm/memory.c | 2
9 files changed, 709 insertions(+)
create mode 100644 arch/arm/include/asm/kvm_mmu.h
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index c196a22..f6e8f6f 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -21,4 +21,111 @@
#include <asm/types.h>
+/* Hyp Configuration Register (HCR) bits */
+#define HCR_TGE (1 << 27)
+#define HCR_TVM (1 << 26)
+#define HCR_TTLB (1 << 25)
+#define HCR_TPU (1 << 24)
+#define HCR_TPC (1 << 23)
+#define HCR_TSW (1 << 22)
+#define HCR_TAC (1 << 21)
+#define HCR_TIDCP (1 << 20)
+#define HCR_TSC (1 << 19)
+#define HCR_TID3 (1 << 18)
+#define HCR_TID2 (1 << 17)
+#define HCR_TID1 (1 << 16)
+#define HCR_TID0 (1 << 15)
+#define HCR_TWE (1 << 14)
+#define HCR_TWI (1 << 13)
+#define HCR_DC (1 << 12)
+#define HCR_BSU (3 << 10)
+#define HCR_BSU_IS (1 << 10)
+#define HCR_FB (1 << 9)
+#define HCR_VA (1 << 8)
+#define HCR_VI (1 << 7)
+#define HCR_VF (1 << 6)
+#define HCR_AMO (1 << 5)
+#define HCR_IMO (1 << 4)
+#define HCR_FMO (1 << 3)
+#define HCR_PTW (1 << 2)
+#define HCR_SWIO (1 << 1)
+#define HCR_VM 1
+
+/*
+ * The bits we set in HCR:
+ * TAC: Trap ACTLR
+ * TSC: Trap SMC
+ * TSW: Trap cache operations by set/way
+ * TWI: Trap WFI
+ * TIDCP: Trap L2CTLR/L2ECTLR
+ * BSU_IS: Upgrade barriers to the inner shareable domain
+ * FB: Force broadcast of all maintainance operations
+ * AMO: Override CPSR.A and enable signaling with VA
+ * IMO: Override CPSR.I and enable signaling with VI
+ * FMO: Override CPSR.F and enable signaling with VF
+ * SWIO: Turn set/way invalidates into set/way clean+invalidate
+ */
+#define HCR_GUEST_MASK (HCR_TSC | HCR_TSW | HCR_TWI | HCR_VM | HCR_BSU_IS | \
+ HCR_FB | HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | \
+ HCR_SWIO | HCR_TIDCP)
+
+/* Hyp System Control Register (HSCTLR) bits */
+#define HSCTLR_TE (1 << 30)
+#define HSCTLR_EE (1 << 25)
+#define HSCTLR_FI (1 << 21)
+#define HSCTLR_WXN (1 << 19)
+#define HSCTLR_I (1 << 12)
+#define HSCTLR_C (1 << 2)
+#define HSCTLR_A (1 << 1)
+#define HSCTLR_M 1
+#define HSCTLR_MASK (HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I | \
+ HSCTLR_WXN | HSCTLR_FI | HSCTLR_EE | HSCTLR_TE)
+
+/* TTBCR and HTCR Registers bits */
+#define TTBCR_EAE (1 << 31)
+#define TTBCR_IMP (1 << 30)
+#define TTBCR_SH1 (3 << 28)
+#define TTBCR_ORGN1 (3 << 26)
+#define TTBCR_IRGN1 (3 << 24)
+#define TTBCR_EPD1 (1 << 23)
+#define TTBCR_A1 (1 << 22)
+#define TTBCR_T1SZ (3 << 16)
+#define TTBCR_SH0 (3 << 12)
+#define TTBCR_ORGN0 (3 << 10)
+#define TTBCR_IRGN0 (3 << 8)
+#define TTBCR_EPD0 (1 << 7)
+#define TTBCR_T0SZ 3
+#define HTCR_MASK (TTBCR_T0SZ | TTBCR_IRGN0 | TTBCR_ORGN0 | TTBCR_SH0)
+
+/* Hyp Debug Configuration Register bits */
+#define HDCR_TDRA (1 << 11)
+#define HDCR_TDOSA (1 << 10)
+#define HDCR_TDA (1 << 9)
+#define HDCR_TDE (1 << 8)
+#define HDCR_HPME (1 << 7)
+#define HDCR_TPM (1 << 6)
+#define HDCR_TPMCR (1 << 5)
+#define HDCR_HPMN_MASK (0x1F)
+
+/* Virtualization Translation Control Register (VTCR) bits */
+#define VTCR_SH0 (3 << 12)
+#define VTCR_ORGN0 (3 << 10)
+#define VTCR_IRGN0 (3 << 8)
+#define VTCR_SL0 (3 << 6)
+#define VTCR_S (1 << 4)
+#define VTCR_T0SZ 3
+#define VTCR_MASK (VTCR_SH0 | VTCR_ORGN0 | VTCR_IRGN0 | VTCR_SL0 | \
+ VTCR_S | VTCR_T0SZ | VTCR_MASK)
+#define VTCR_HTCR_SH (VTCR_SH0 | VTCR_ORGN0 | VTCR_IRGN0)
+#define VTCR_SL_L2 0 /* Starting-level: 2 */
+#define VTCR_SL_L1 (1 << 6) /* Starting-level: 1 */
+#define VTCR_GUEST_SL VTCR_SL_L1
+#define VTCR_GUEST_T0SZ 0
+#if VTCR_GUEST_SL == 0
+#define VTTBR_X (14 - VTCR_GUEST_T0SZ)
+#else
+#define VTTBR_X (5 - VTCR_GUEST_T0SZ)
+#endif
+
+
#endif /* __ARM_KVM_ARM_H__ */
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 48ddf99..954bf7c 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -54,5 +54,25 @@
#define ARM_EXCEPTION_DATA_ABORT 4
#define ARM_EXCEPTION_IRQ 5
#define ARM_EXCEPTION_FIQ 6
+#define ARM_EXCEPTION_HVC 7
+
+#ifndef __ASSEMBLY__
+struct kvm_vcpu;
+
+extern char __kvm_hyp_init[];
+extern char __kvm_hyp_init_end[];
+
+extern char __kvm_hyp_exit[];
+extern char __kvm_hyp_exit_end[];
+
+extern char __kvm_hyp_vector[];
+
+extern char __kvm_hyp_code_start[];
+extern char __kvm_hyp_code_end[];
+
+extern void __kvm_flush_vm_context(void);
+
+extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
+#endif
#endif /* __ARM_KVM_ASM_H__ */
diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
new file mode 100644
index 0000000..741ab8f
--- /dev/null
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_MMU_H__
+#define __ARM_KVM_MMU_H__
+
+/*
+ * The architecture supports 40-bit IPA as input to the 2nd stage translations
+ * and PTRS_PER_PGD2 could therefore be 1024.
+ *
+ * To save a bit of memory and to avoid alignment issues we assume 39-bit IPA
+ * for now, but remember that the level-1 table must be aligned to its size.
+ */
+#define PTRS_PER_PGD2 512
+#define PGD2_ORDER get_order(PTRS_PER_PGD2 * sizeof(pgd_t))
+
+int create_hyp_mappings(void *from, void *to);
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
+void free_hyp_pmds(void);
+
+unsigned long kvm_mmu_get_httbr(void);
+int kvm_mmu_init(void);
+void kvm_mmu_exit(void);
+#endif /* __ARM_KVM_MMU_H__ */
diff --git a/arch/arm/include/asm/pgtable-3level-hwdef.h b/arch/arm/include/asm/pgtable-3level-hwdef.h
index a2d404e..18f5cef 100644
--- a/arch/arm/include/asm/pgtable-3level-hwdef.h
+++ b/arch/arm/include/asm/pgtable-3level-hwdef.h
@@ -32,6 +32,9 @@
#define PMD_TYPE_SECT (_AT(pmdval_t, 1) << 0)
#define PMD_BIT4 (_AT(pmdval_t, 0))
#define PMD_DOMAIN(x) (_AT(pmdval_t, 0))
+#define PMD_APTABLE_SHIFT (61)
+#define PMD_APTABLE (_AT(pgdval_t, 3) << PGD_APTABLE_SHIFT)
+#define PMD_PXNTABLE (_AT(pgdval_t, 1) << 59)
/*
* - section
@@ -41,6 +44,7 @@
#define PMD_SECT_S (_AT(pmdval_t, 3) << 8)
#define PMD_SECT_AF (_AT(pmdval_t, 1) << 10)
#define PMD_SECT_nG (_AT(pmdval_t, 1) << 11)
+#define PMD_SECT_PXN (_AT(pmdval_t, 1) << 53)
#define PMD_SECT_XN (_AT(pmdval_t, 1) << 54)
#define PMD_SECT_AP_WRITE (_AT(pmdval_t, 0))
#define PMD_SECT_AP_READ (_AT(pmdval_t, 0))
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index ead5a4e..8e1ea2b 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -34,11 +34,21 @@
#include <asm/ptrace.h>
#include <asm/mman.h>
#include <asm/cputype.h>
+#include <asm/tlbflush.h>
+#include <asm/virt.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_mmu.h>
#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
#endif
+static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
+static struct vfp_hard_struct __percpu *kvm_host_vfp_state;
+static unsigned long hyp_default_vectors;
+
+
int kvm_arch_hardware_enable(void *garbage)
{
return 0;
@@ -324,9 +334,171 @@ long kvm_arch_vm_ioctl(struct file *filp,
return -EINVAL;
}
+static void cpu_init_hyp_mode(void *vector)
+{
+ unsigned long pgd_ptr;
+ unsigned long hyp_stack_ptr;
+ unsigned long stack_page;
+ unsigned long vector_ptr;
+
+ /* Switch from the HYP stub to our own HYP init vector */
+ __hyp_set_vectors((unsigned long)vector);
+
+ pgd_ptr = kvm_mmu_get_httbr();
+ stack_page = __get_cpu_var(kvm_arm_hyp_stack_page);
+ hyp_stack_ptr = stack_page + PAGE_SIZE;
+ vector_ptr = (unsigned long)__kvm_hyp_vector;
+
+ /*
+ * Call initialization code, and switch to the full blown
+ * HYP code. The init code corrupts r12, so set the clobber
+ * list accordingly.
+ */
+ asm volatile (
+ "mov r0, %[pgd_ptr]\n\t"
+ "mov r1, %[hyp_stack_ptr]\n\t"
+ "mov r2, %[vector_ptr]\n\t"
+ "hvc #0\n\t" : :
+ [pgd_ptr] "r" (pgd_ptr),
+ [hyp_stack_ptr] "r" (hyp_stack_ptr),
+ [vector_ptr] "r" (vector_ptr) :
+ "r0", "r1", "r2", "r12");
+}
+
+/**
+ * Inits Hyp-mode on all online CPUs
+ */
+static int init_hyp_mode(void)
+{
+ phys_addr_t init_phys_addr;
+ int cpu;
+ int err = 0;
+
+ /*
+ * Allocate Hyp PGD and setup Hyp identity mapping
+ */
+ err = kvm_mmu_init();
+ if (err)
+ return err;
+
+ /*
+ * It is probably enough to obtain the default on one
+ * CPU. It's unlikely to be different on the others.
+ */
+ hyp_default_vectors = __hyp_get_vectors();
+
+ /*
+ * Allocate stack pages for Hypervisor-mode
+ */
+ for_each_possible_cpu(cpu) {
+ unsigned long stack_page;
+
+ stack_page = __get_free_page(GFP_KERNEL);
+ if (!stack_page) {
+ err = -ENOMEM;
+ goto out_free_stack_pages;
+ }
+
+ per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page;
+ }
+
+ /*
+ * Execute the init code on each CPU.
+ *
+ * Note: The stack is not mapped yet, so don't do anything else than
+ * initializing the hypervisor mode on each CPU using a local stack
+ * space for temporary storage.
+ */
+ init_phys_addr = virt_to_phys(__kvm_hyp_init);
+ for_each_online_cpu(cpu) {
+ smp_call_function_single(cpu, cpu_init_hyp_mode,
+ (void *)(long)init_phys_addr, 1);
+ }
+
+ /*
+ * Unmap the identity mapping
+ */
+ kvm_mmu_exit();
+
+ /*
+ * Map the Hyp-code called directly from the host
+ */
+ err = create_hyp_mappings(__kvm_hyp_code_start, __kvm_hyp_code_end);
+ if (err) {
+ kvm_err("Cannot map world-switch code\n");
+ goto out_free_mappings;
+ }
+
+ /*
+ * Map the Hyp stack pages
+ */
+ for_each_possible_cpu(cpu) {
+ char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
+ err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE);
+
+ if (err) {
+ kvm_err("Cannot map hyp stack\n");
+ goto out_free_mappings;
+ }
+ }
+
+ /*
+ * Map the host VFP structures
+ */
+ kvm_host_vfp_state = alloc_percpu(struct vfp_hard_struct);
+ if (!kvm_host_vfp_state) {
+ err = -ENOMEM;
+ kvm_err("Cannot allocate host VFP state\n");
+ goto out_free_mappings;
+ }
+
+ for_each_possible_cpu(cpu) {
+ struct vfp_hard_struct *vfp;
+
+ vfp = per_cpu_ptr(kvm_host_vfp_state, cpu);
+ err = create_hyp_mappings(vfp, vfp + 1);
+
+ if (err) {
+ kvm_err("Cannot map host VFP state: %d\n", err);
+ goto out_free_vfp;
+ }
+ }
+
+ return 0;
+out_free_vfp:
+ free_percpu(kvm_host_vfp_state);
+out_free_mappings:
+ free_hyp_pmds();
+out_free_stack_pages:
+ for_each_possible_cpu(cpu)
+ free_page(per_cpu(kvm_arm_hyp_stack_page, cpu));
+ return err;
+}
+
+/**
+ * Initialize Hyp-mode and memory mappings on all CPUs.
+ */
int kvm_arch_init(void *opaque)
{
+ int err;
+
+ if (!is_hyp_mode_available()) {
+ kvm_err("HYP mode not available\n");
+ return -ENODEV;
+ }
+
+ if (kvm_target_cpu() < 0) {
+ kvm_err("Target CPU not supported!\n");
+ return -ENODEV;
+ }
+
+ err = init_hyp_mode();
+ if (err)
+ goto out_err;
+
return 0;
+out_err:
+ return err;
}
/* NOP: Compiling as a module not supported */
diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S
index 1dc8926..3e0690b 100644
--- a/arch/arm/kvm/init.S
+++ b/arch/arm/kvm/init.S
@@ -15,5 +15,112 @@
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+
+#include <linux/linkage.h>
+#include <asm/unified.h>
#include <asm/asm-offsets.h>
#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+
+/********************************************************************
+ * Hypervisor initialization
+ * - should be called with:
+ * r0 = Hypervisor pgd pointer
+ * r1 = top of Hyp stack (kernel VA)
+ * r2 = pointer to hyp vectors
+ */
+
+ .text
+ .pushsection .hyp.idmap.text,"ax"
+ .align 12
+__kvm_hyp_init:
+ .globl __kvm_hyp_init
+
+ @ Hyp-mode exception vector
+ W(b) .
+ W(b) .
+ W(b) .
+ W(b) .
+ W(b) .
+ W(b) __do_hyp_init
+ W(b) .
+ W(b) .
+
+__do_hyp_init:
+ @ Set the sp to end of this page and push data for later use
+ARM( add r12, pc, #(__kvm_init_sp - .) )
+ARM( sub r12, r12, #8 )
+THUMB( adr r12, __kvm_init_sp )
+ mov sp, r12
+ push {r1, r2}
+
+ @ Set the HTTBR to point to the hypervisor PGD pointer passed to
+ @ function and set the upper bits equal to the kernel PGD.
+ mrrc p15, 1, r1, r2, c2
+ mcrr p15, 4, r0, r2, c2
+
+ @ Set the HTCR and VTCR to the same shareability and cacheability
+ @ settings as the non-secure TTBCR and with T0SZ == 0.
+ mrc p15, 4, r0, c2, c0, 2 @ HTCR
+ ldr r12, =HTCR_MASK
+ bic r0, r0, r12
+ mrc p15, 0, r1, c2, c0, 2 @ TTBCR
+ and r1, r1, #(HTCR_MASK & ~TTBCR_T0SZ)
+ orr r0, r0, r1
+ mcr p15, 4, r0, c2, c0, 2 @ HTCR
+
+ mrc p15, 4, r1, c2, c1, 2 @ VTCR
+ bic r1, r1, #(VTCR_HTCR_SH | VTCR_SL0)
+ bic r0, r0, #(~VTCR_HTCR_SH)
+ orr r1, r0, r1
+ orr r1, r1, #(VTCR_SL_L1 | VTCR_GUEST_T0SZ)
+ mcr p15, 4, r1, c2, c1, 2 @ VTCR
+
+ @ Use the same memory attributes for hyp. accesses as the kernel
+ @ (copy MAIRx ro HMAIRx).
+ mrc p15, 0, r0, c10, c2, 0
+ mcr p15, 4, r0, c10, c2, 0
+ mrc p15, 0, r0, c10, c2, 1
+ mcr p15, 4, r0, c10, c2, 1
+
+ @ Set the HSCTLR to:
+ @ - ARM/THUMB exceptions: Kernel config (Thumb-2 kernel)
+ @ - Endianness: Kernel config
+ @ - Fast Interrupt Features: Kernel config
+ @ - Write permission implies XN: disabled
+ @ - Instruction cache: enabled
+ @ - Data/Unified cache: enabled
+ @ - Memory alignment checks: enabled
+ @ - MMU: enabled (this code must be run from an identity mapping)
+ mrc p15, 4, r0, c1, c0, 0 @ HSCR
+ ldr r12, =HSCTLR_MASK
+ bic r0, r0, r12
+ mrc p15, 0, r1, c1, c0, 0 @ SCTLR
+ ldr r12, =(HSCTLR_EE | HSCTLR_FI)
+ and r1, r1, r12
+ ARM( ldr r12, =(HSCTLR_M | HSCTLR_A | HSCTLR_I) )
+ THUMB( ldr r12, =(HSCTLR_M | HSCTLR_A | HSCTLR_I | HSCTLR_TE) )
+ orr r1, r1, r12
+ orr r0, r0, r1
+ isb
+ mcr p15, 4, r0, c1, c0, 0 @ HSCR
+ isb
+
+ @ Set stack pointer and return to the kernel
+ pop {r1, r2}
+ mov sp, r1
+
+ @ Set HVBAR to point to the HYP vectors
+ mcr p15, 4, r2, c12, c0, 0 @ HVBAR
+
+ eret
+
+ .ltorg
+
+ .align 12
+
+ __kvm_init_sp:
+ .globl __kvm_hyp_init_end
+__kvm_hyp_init_end:
+
+ .popsection
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 1dc8926..98a67ca 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -15,5 +15,53 @@
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+
+#include <linux/linkage.h>
+#include <linux/const.h>
+#include <asm/unified.h>
+#include <asm/page.h>
#include <asm/asm-offsets.h>
#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+
+ .text
+ .align PAGE_SHIFT
+
+__kvm_hyp_code_start:
+ .globl __kvm_hyp_code_start
+
+/********************************************************************
+ * Flush per-VMID TLBs
+ */
+
+ENTRY(__kvm_flush_vm_context)
+ bx lr
+ENDPROC(__kvm_flush_vm_context)
+
+/********************************************************************
+ * Hypervisor world-switch code
+ */
+
+ENTRY(__kvm_vcpu_run)
+ bx lr
+
+
+/********************************************************************
+ * Hypervisor exception vector and handlers
+ */
+
+ .align 5
+__kvm_hyp_vector:
+ .globl __kvm_hyp_vector
+ nop
+
+/*
+ * The below lines makes sure the HYP mode code fits in a single page (the
+ * assembler will bark at you if it doesn't). Please keep them together. If
+ * you plan to restructure the code or increase its size over a page, you'll
+ * have to fix the code in init_hyp_mode().
+ */
+__kvm_hyp_code_end:
+ .globl __kvm_hyp_code_end
+
+ .org __kvm_hyp_code_start + PAGE_SIZE
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 10ed464..17c2bf5 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -15,3 +15,213 @@
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+
+#include <linux/mman.h>
+#include <linux/kvm_host.h>
+#include <linux/io.h>
+#include <asm/idmap.h>
+#include <asm/pgalloc.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+#include <asm/mach/map.h>
+
+static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
+static pgd_t *hyp_pgd;
+
+static void free_ptes(pmd_t *pmd, unsigned long addr)
+{
+ pte_t *pte;
+ unsigned int i;
+
+ for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
+ if (!pmd_none(*pmd) && pmd_table(*pmd)) {
+ pte = pte_offset_kernel(pmd, addr);
+ pte_free_kernel(NULL, pte);
+ }
+ pmd++;
+ }
+}
+
+/**
+ * free_hyp_pmds - free a Hyp-mode level-2 tables and child level-3 tables
+ *
+ * Assumes this is a page table used strictly in Hyp-mode and therefore contains
+ * only mappings in the kernel memory area, which is above PAGE_OFFSET.
+ */
+void free_hyp_pmds(void)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ unsigned long addr;
+
+ mutex_lock(&kvm_hyp_pgd_mutex);
+ for (addr = PAGE_OFFSET; addr != 0; addr += PGDIR_SIZE) {
+ pgd = hyp_pgd + pgd_index(addr);
+ pud = pud_offset(pgd, addr);
+
+ if (pud_none(*pud))
+ continue;
+ BUG_ON(pud_bad(*pud));
+
+ pmd = pmd_offset(pud, addr);
+ free_ptes(pmd, addr);
+ pmd_free(NULL, pmd);
+ pud_clear(pud);
+ }
+ mutex_unlock(&kvm_hyp_pgd_mutex);
+}
+
+/*
+ * Create a HYP pte mapping.
+ *
+ * If pfn_base is NULL, we map kernel pages into HYP with the virtual
+ * address. Otherwise, this is considered an I/O mapping and we map
+ * the physical region starting@*pfn_base to [start, end[.
+ */
+static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
+ unsigned long end, unsigned long *pfn_base)
+{
+ pte_t *pte;
+ unsigned long addr;
+ pgprot_t prot;
+
+ if (pfn_base)
+ prot = PAGE_HYP_DEVICE;
+ else
+ prot = PAGE_HYP;
+
+ for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
+ pte = pte_offset_kernel(pmd, addr);
+ if (pfn_base) {
+ BUG_ON(pfn_valid(*pfn_base));
+ set_pte_ext(pte, pfn_pte(*pfn_base, prot), 0);
+ (*pfn_base)++;
+ } else {
+ struct page *page;
+ BUG_ON(!virt_addr_valid(addr));
+ page = virt_to_page(addr);
+ set_pte_ext(pte, mk_pte(page, prot), 0);
+ }
+
+ }
+}
+
+static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
+ unsigned long end, unsigned long *pfn_base)
+{
+ pmd_t *pmd;
+ pte_t *pte;
+ unsigned long addr, next;
+
+ for (addr = start; addr < end; addr = next) {
+ pmd = pmd_offset(pud, addr);
+
+ BUG_ON(pmd_sect(*pmd));
+
+ if (pmd_none(*pmd)) {
+ pte = pte_alloc_one_kernel(NULL, addr);
+ if (!pte) {
+ kvm_err("Cannot allocate Hyp pte\n");
+ return -ENOMEM;
+ }
+ pmd_populate_kernel(NULL, pmd, pte);
+ }
+
+ next = pmd_addr_end(addr, end);
+ create_hyp_pte_mappings(pmd, addr, next, pfn_base);
+ }
+
+ return 0;
+}
+
+static int __create_hyp_mappings(void *from, void *to, unsigned long *pfn_base)
+{
+ unsigned long start = (unsigned long)from;
+ unsigned long end = (unsigned long)to;
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ unsigned long addr, next;
+ int err = 0;
+
+ BUG_ON(start > end);
+ if (start < PAGE_OFFSET)
+ return -EINVAL;
+
+ mutex_lock(&kvm_hyp_pgd_mutex);
+ for (addr = start; addr < end; addr = next) {
+ pgd = hyp_pgd + pgd_index(addr);
+ pud = pud_offset(pgd, addr);
+
+ if (pud_none_or_clear_bad(pud)) {
+ pmd = pmd_alloc_one(NULL, addr);
+ if (!pmd) {
+ kvm_err("Cannot allocate Hyp pmd\n");
+ err = -ENOMEM;
+ goto out;
+ }
+ pud_populate(NULL, pud, pmd);
+ }
+
+ next = pgd_addr_end(addr, end);
+ err = create_hyp_pmd_mappings(pud, addr, next, pfn_base);
+ if (err)
+ goto out;
+ }
+out:
+ mutex_unlock(&kvm_hyp_pgd_mutex);
+ return err;
+}
+
+/**
+ * create_hyp_mappings - map a kernel virtual address range in Hyp mode
+ * @from: The virtual kernel start address of the range
+ * @to: The virtual kernel end address of the range (exclusive)
+ *
+ * The same virtual address as the kernel virtual address is also used in
+ * Hyp-mode mapping to the same underlying physical pages.
+ *
+ * Note: Wrapping around zero in the "to" address is not supported.
+ */
+int create_hyp_mappings(void *from, void *to)
+{
+ return __create_hyp_mappings(from, to, NULL);
+}
+
+/**
+ * create_hyp_io_mappings - map a physical IO range in Hyp mode
+ * @from: The virtual HYP start address of the range
+ * @to: The virtual HYP end address of the range (exclusive)
+ * @addr: The physical start address which gets mapped
+ */
+int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
+{
+ unsigned long pfn = __phys_to_pfn(addr);
+ return __create_hyp_mappings(from, to, &pfn);
+}
+
+int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ return -EINVAL;
+}
+
+unsigned long kvm_mmu_get_httbr(void)
+{
+ return virt_to_phys(hyp_pgd);
+}
+
+int kvm_mmu_init(void)
+{
+ hyp_pgd = kzalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL);
+ if (!hyp_pgd)
+ return -ENOMEM;
+
+ hyp_idmap_setup(hyp_pgd);
+ return 0;
+}
+
+void kvm_mmu_exit(void)
+{
+ hyp_idmap_teardown(hyp_pgd);
+}
diff --git a/mm/memory.c b/mm/memory.c
index fb135ba..5ae0164 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -383,12 +383,14 @@ void pgd_clear_bad(pgd_t *pgd)
pgd_ERROR(*pgd);
pgd_clear(pgd);
}
+EXPORT_SYMBOL_GPL(pgd_clear_bad);
void pud_clear_bad(pud_t *pud)
{
pud_ERROR(*pud);
pud_clear(pud);
}
+EXPORT_SYMBOL_GPL(pud_clear_bad);
void pmd_clear_bad(pmd_t *pmd)
{
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 06/14] KVM: ARM: Memory virtualization setup
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (4 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 05/14] KVM: ARM: Hypervisor inititalization Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-11-19 11:29 ` [kvmarm] " Sundaram, Senthilkumar
2012-10-22 6:49 ` [PATCH v3 07/14] KVM: ARM: Inject IRQs and FIQs from userspace Christoffer Dall
` (7 subsequent siblings)
13 siblings, 1 reply; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
This commit introduces the framework for guest memory management
through the use of 2nd stage translation. Each VM has a pointer
to a level-1 table (the pgd field in struct kvm_arch) which is
used for the 2nd stage translations. Entries are added when handling
guest faults (later patch) and the table itself can be allocated and
freed through the following functions implemented in
arch/arm/kvm/arm_mmu.c:
- kvm_alloc_stage2_pgd(struct kvm *kvm);
- kvm_free_stage2_pgd(struct kvm *kvm);
Each entry in TLBs and caches are tagged with a VMID identifier in
addition to ASIDs. The VMIDs are assigned consecutively to VMs in the
order that VMs are executed, and caches and tlbs are invalidated when
the VMID space has been used to allow for more than 255 simultaenously
running guests.
The 2nd stage pgd is allocated in kvm_arch_init_vm(). The table is
freed in kvm_arch_destroy_vm(). Both functions are called from the main
KVM code.
We pre-allocate page table memory to be able to synchronize using a
spinlock and be called under rcu_read_lock from the MMU notifiers. We
steal the mmu_memory_cache implementation from x86 and adapt for our
specific usage.
We support MMU notifiers (thanks to Marc Zyngier) through
kvm_unmap_hva and kvm_set_spte_hva.
Finally, define kvm_phys_addr_ioremap() to map a device at a guest IPA,
which is used by VGIC support to map the virtual CPU interface registers
to the guest. This support is added by Marc Zyngier.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_asm.h | 2
arch/arm/include/asm/kvm_host.h | 19 ++
arch/arm/include/asm/kvm_mmu.h | 9 +
arch/arm/kvm/Kconfig | 1
arch/arm/kvm/arm.c | 37 ++++
arch/arm/kvm/interrupts.S | 10 +
arch/arm/kvm/mmu.c | 393 +++++++++++++++++++++++++++++++++++++++
arch/arm/kvm/trace.h | 46 +++++
8 files changed, 515 insertions(+), 2 deletions(-)
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 954bf7c..47a0e57 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -57,6 +57,7 @@
#define ARM_EXCEPTION_HVC 7
#ifndef __ASSEMBLY__
+struct kvm;
struct kvm_vcpu;
extern char __kvm_hyp_init[];
@@ -71,6 +72,7 @@ extern char __kvm_hyp_code_start[];
extern char __kvm_hyp_code_end[];
extern void __kvm_flush_vm_context(void);
+extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
#endif
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 15d4c0b..68d1005 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -117,4 +117,23 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
struct kvm_one_reg;
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
+u64 kvm_call_hyp(void *hypfn, ...);
+
+#define KVM_ARCH_WANT_MMU_NOTIFIER
+struct kvm;
+int kvm_unmap_hva(struct kvm *kvm, unsigned long hva);
+int kvm_unmap_hva_range(struct kvm *kvm,
+ unsigned long start, unsigned long end);
+void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
+
+/* We do not have shadow page tables, hence the empty hooks */
+static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva)
+{
+ return 0;
+}
+
+static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
+{
+ return 0;
+}
#endif /* __ARM_KVM_HOST_H__ */
diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h
index 741ab8f..9bd0508 100644
--- a/arch/arm/include/asm/kvm_mmu.h
+++ b/arch/arm/include/asm/kvm_mmu.h
@@ -33,6 +33,15 @@ int create_hyp_mappings(void *from, void *to);
int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
void free_hyp_pmds(void);
+int kvm_alloc_stage2_pgd(struct kvm *kvm);
+void kvm_free_stage2_pgd(struct kvm *kvm);
+int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
+ phys_addr_t pa, unsigned long size);
+
+int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run);
+
+void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
+
unsigned long kvm_mmu_get_httbr(void);
int kvm_mmu_init(void);
void kvm_mmu_exit(void);
diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index a07ddcc..47c5500 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -36,6 +36,7 @@ config KVM_ARM_HOST
depends on KVM
depends on MMU
depends on CPU_V7 && ARM_VIRT_EXT
+ select MMU_NOTIFIER
---help---
Provides host support for ARM processors.
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 8e1ea2b..5ac3132 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -81,12 +81,33 @@ void kvm_arch_sync_events(struct kvm *kvm)
{
}
+/**
+ * kvm_arch_init_vm - initializes a VM data structure
+ * @kvm: pointer to the KVM struct
+ */
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
+ int ret = 0;
+
if (type)
return -EINVAL;
- return 0;
+ ret = kvm_alloc_stage2_pgd(kvm);
+ if (ret)
+ goto out_fail_alloc;
+
+ ret = create_hyp_mappings(kvm, kvm + 1);
+ if (ret)
+ goto out_free_stage2_pgd;
+
+ /* Mark the initial VMID generation invalid */
+ kvm->arch.vmid_gen = 0;
+
+ return ret;
+out_free_stage2_pgd:
+ kvm_free_stage2_pgd(kvm);
+out_fail_alloc:
+ return ret;
}
int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
@@ -104,10 +125,16 @@ int kvm_arch_create_memslot(struct kvm_memory_slot *slot, unsigned long npages)
return 0;
}
+/**
+ * kvm_arch_destroy_vm - destroy the VM data structure
+ * @kvm: pointer to the KVM struct
+ */
void kvm_arch_destroy_vm(struct kvm *kvm)
{
int i;
+ kvm_free_stage2_pgd(kvm);
+
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (kvm->vcpus[i]) {
kvm_arch_vcpu_free(kvm->vcpus[i]);
@@ -189,7 +216,13 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
if (err)
goto free_vcpu;
+ err = create_hyp_mappings(vcpu, vcpu + 1);
+ if (err)
+ goto vcpu_uninit;
+
return vcpu;
+vcpu_uninit:
+ kvm_vcpu_uninit(vcpu);
free_vcpu:
kmem_cache_free(kvm_vcpu_cache, vcpu);
out:
@@ -198,6 +231,8 @@ out:
void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
{
+ kvm_mmu_free_memory_caches(vcpu);
+ kmem_cache_free(kvm_vcpu_cache, vcpu);
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 98a67ca..1c83022 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -33,7 +33,13 @@ __kvm_hyp_code_start:
/********************************************************************
* Flush per-VMID TLBs
*/
+ENTRY(__kvm_tlb_flush_vmid)
+ bx lr
+ENDPROC(__kvm_tlb_flush_vmid)
+/********************************************************************
+ * Flush TLBs and instruction caches of current CPU for all VMIDs
+ */
ENTRY(__kvm_flush_vm_context)
bx lr
ENDPROC(__kvm_flush_vm_context)
@@ -41,10 +47,12 @@ ENDPROC(__kvm_flush_vm_context)
/********************************************************************
* Hypervisor world-switch code
*/
-
ENTRY(__kvm_vcpu_run)
bx lr
+ENTRY(kvm_call_hyp)
+ bx lr
+
/********************************************************************
* Hypervisor exception vector and handlers
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 17c2bf5..f45be86 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -23,11 +23,52 @@
#include <asm/pgalloc.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
+#include <asm/kvm_asm.h>
#include <asm/mach/map.h>
+#include <trace/events/kvm.h>
+
+#include "trace.h"
static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
static pgd_t *hyp_pgd;
+static void kvm_tlb_flush_vmid(struct kvm *kvm)
+{
+ kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
+}
+
+static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
+ int min, int max)
+{
+ void *page;
+
+ BUG_ON(max > KVM_NR_MEM_OBJS);
+ if (cache->nobjs >= min)
+ return 0;
+ while (cache->nobjs < max) {
+ page = (void *)__get_free_page(PGALLOC_GFP);
+ if (!page)
+ return -ENOMEM;
+ cache->objects[cache->nobjs++] = page;
+ }
+ return 0;
+}
+
+static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
+{
+ while (mc->nobjs)
+ free_page((unsigned long)mc->objects[--mc->nobjs]);
+}
+
+static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
+{
+ void *p;
+
+ BUG_ON(!mc || !mc->nobjs);
+ p = mc->objects[--mc->nobjs];
+ return p;
+}
+
static void free_ptes(pmd_t *pmd, unsigned long addr)
{
pte_t *pte;
@@ -201,11 +242,363 @@ int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
return __create_hyp_mappings(from, to, &pfn);
}
+/**
+ * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
+ * @kvm: The KVM struct pointer for the VM.
+ *
+ * Allocates the 1st level table only of size defined by PGD2_ORDER (can
+ * support either full 40-bit input addresses or limited to 32-bit input
+ * addresses). Clears the allocated pages.
+ *
+ * Note we don't need locking here as this is only called when the VM is
+ * created, which can only be done once.
+ */
+int kvm_alloc_stage2_pgd(struct kvm *kvm)
+{
+ pgd_t *pgd;
+
+ if (kvm->arch.pgd != NULL) {
+ kvm_err("kvm_arch already initialized?\n");
+ return -EINVAL;
+ }
+
+ pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, PGD2_ORDER);
+ if (!pgd)
+ return -ENOMEM;
+
+ memset(pgd, 0, PTRS_PER_PGD2 * sizeof(pgd_t));
+ clean_dcache_area(pgd, PTRS_PER_PGD2 * sizeof(pgd_t));
+ kvm->arch.pgd = pgd;
+
+ return 0;
+}
+
+static void free_guest_pages(pte_t *pte, unsigned long addr)
+{
+ unsigned int i;
+ struct page *pte_page;
+
+ pte_page = virt_to_page(pte);
+
+ for (i = 0; i < PTRS_PER_PTE; i++) {
+ if (pte_present(*pte))
+ put_page(pte_page);
+ pte++;
+ }
+
+ WARN_ON(page_count(pte_page) != 1);
+}
+
+static void free_stage2_ptes(pmd_t *pmd, unsigned long addr)
+{
+ unsigned int i;
+ pte_t *pte;
+ struct page *pmd_page;
+
+ pmd_page = virt_to_page(pmd);
+
+ for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
+ BUG_ON(pmd_sect(*pmd));
+ if (!pmd_none(*pmd) && pmd_table(*pmd)) {
+ pte = pte_offset_kernel(pmd, addr);
+ free_guest_pages(pte, addr);
+ pte_free_kernel(NULL, pte);
+
+ put_page(pmd_page);
+ }
+ pmd++;
+ }
+
+ WARN_ON(page_count(pmd_page) != 1);
+}
+
+/**
+ * kvm_free_stage2_pgd - free all stage-2 tables
+ * @kvm: The KVM struct pointer for the VM.
+ *
+ * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
+ * underlying level-2 and level-3 tables before freeing the actual level-1 table
+ * and setting the struct pointer to NULL.
+ *
+ * Note we don't need locking here as this is only called when the VM is
+ * destroyed, which can only be done once.
+ */
+void kvm_free_stage2_pgd(struct kvm *kvm)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ unsigned long long i, addr;
+ struct page *pud_page;
+
+ if (kvm->arch.pgd == NULL)
+ return;
+
+ /*
+ * We do this slightly different than other places, since we need more
+ * than 32 bits and for instance pgd_addr_end converts to unsigned long.
+ */
+ addr = 0;
+ for (i = 0; i < PTRS_PER_PGD2; i++) {
+ addr = i * (unsigned long long)PGDIR_SIZE;
+ pgd = kvm->arch.pgd + i;
+ pud = pud_offset(pgd, addr);
+ pud_page = virt_to_page(pud);
+
+ if (pud_none(*pud))
+ continue;
+
+ BUG_ON(pud_bad(*pud));
+
+ pmd = pmd_offset(pud, addr);
+ free_stage2_ptes(pmd, addr);
+ pmd_free(NULL, pmd);
+ put_page(pud_page);
+ }
+
+ WARN_ON(page_count(pud_page) != 1);
+ free_pages((unsigned long)kvm->arch.pgd, PGD2_ORDER);
+ kvm->arch.pgd = NULL;
+}
+
+/**
+ * stage2_clear_pte -- Clear a stage-2 PTE.
+ * @kvm: The VM pointer
+ * @addr: The physical address of the PTE
+ *
+ * Clear a stage-2 PTE, lowering the various ref-counts. Also takes
+ * care of invalidating the TLBs. Must be called while holding
+ * mmu_lock, otherwise another faulting VCPU may come in and mess
+ * things behind our back.
+ */
+static void stage2_clear_pte(struct kvm *kvm, phys_addr_t addr)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ struct page *page;
+
+ pgd = kvm->arch.pgd + pgd_index(addr);
+ pud = pud_offset(pgd, addr);
+ if (pud_none(*pud))
+ return;
+
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ return;
+
+ pte = pte_offset_kernel(pmd, addr);
+ set_pte_ext(pte, __pte(0), 0);
+
+ page = virt_to_page(pte);
+ put_page(page);
+ if (page_count(page) != 1) {
+ kvm_tlb_flush_vmid(kvm);
+ return;
+ }
+
+ /* Need to remove pte page */
+ pmd_clear(pmd);
+ pte_free_kernel(NULL, (pte_t *)((unsigned long)pte & PAGE_MASK));
+
+ page = virt_to_page(pmd);
+ put_page(page);
+ if (page_count(page) != 1) {
+ kvm_tlb_flush_vmid(kvm);
+ return;
+ }
+
+ pud_clear(pud);
+ pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
+
+ page = virt_to_page(pud);
+ put_page(page);
+ kvm_tlb_flush_vmid(kvm);
+}
+
+static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
+ phys_addr_t addr, const pte_t *new_pte, bool iomap)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte, old_pte;
+
+ /* Create 2nd stage page table mapping - Level 1 */
+ pgd = kvm->arch.pgd + pgd_index(addr);
+ pud = pud_offset(pgd, addr);
+ if (pud_none(*pud)) {
+ if (!cache)
+ return 0; /* ignore calls from kvm_set_spte_hva */
+ pmd = mmu_memory_cache_alloc(cache);
+ pud_populate(NULL, pud, pmd);
+ pmd += pmd_index(addr);
+ get_page(virt_to_page(pud));
+ } else
+ pmd = pmd_offset(pud, addr);
+
+ /* Create 2nd stage page table mapping - Level 2 */
+ if (pmd_none(*pmd)) {
+ if (!cache)
+ return 0; /* ignore calls from kvm_set_spte_hva */
+ pte = mmu_memory_cache_alloc(cache);
+ clean_pte_table(pte);
+ pmd_populate_kernel(NULL, pmd, pte);
+ pte += pte_index(addr);
+ get_page(virt_to_page(pmd));
+ } else
+ pte = pte_offset_kernel(pmd, addr);
+
+ if (iomap && pte_present(*pte))
+ return -EFAULT;
+
+ /* Create 2nd stage page table mapping - Level 3 */
+ old_pte = *pte;
+ set_pte_ext(pte, *new_pte, 0);
+ if (pte_present(old_pte))
+ kvm_tlb_flush_vmid(kvm);
+ else
+ get_page(virt_to_page(pte));
+
+ return 0;
+}
+
+/**
+ * kvm_phys_addr_ioremap - map a device range to guest IPA
+ *
+ * @kvm: The KVM pointer
+ * @guest_ipa: The IPA at which to insert the mapping
+ * @pa: The physical address of the device
+ * @size: The size of the mapping
+ */
+int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
+ phys_addr_t pa, unsigned long size)
+{
+ phys_addr_t addr, end;
+ int ret = 0;
+ unsigned long pfn;
+ struct kvm_mmu_memory_cache cache = { 0, };
+
+ end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
+ pfn = __phys_to_pfn(pa);
+
+ for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
+ pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE | L_PTE_S2_RDWR);
+
+ ret = mmu_topup_memory_cache(&cache, 2, 2);
+ if (ret)
+ goto out;
+ spin_lock(&kvm->mmu_lock);
+ ret = stage2_set_pte(kvm, &cache, addr, &pte, true);
+ spin_unlock(&kvm->mmu_lock);
+ if (ret)
+ goto out;
+
+ pfn++;
+ }
+
+out:
+ mmu_free_memory_cache(&cache);
+ return ret;
+}
+
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
return -EINVAL;
}
+static void handle_hva_to_gpa(struct kvm *kvm,
+ unsigned long start,
+ unsigned long end,
+ void (*handler)(struct kvm *kvm,
+ gpa_t gpa, void *data),
+ void *data)
+{
+ struct kvm_memslots *slots;
+ struct kvm_memory_slot *memslot;
+
+ slots = kvm_memslots(kvm);
+
+ /* we only care about the pages that the guest sees */
+ kvm_for_each_memslot(memslot, slots) {
+ unsigned long hva_start, hva_end;
+ gfn_t gfn, gfn_end;
+
+ hva_start = max(start, memslot->userspace_addr);
+ hva_end = min(end, memslot->userspace_addr +
+ (memslot->npages << PAGE_SHIFT));
+ if (hva_start >= hva_end)
+ continue;
+
+ /*
+ * {gfn(page) | page intersects with [hva_start, hva_end)} =
+ * {gfn_start, gfn_start+1, ..., gfn_end-1}.
+ */
+ gfn = hva_to_gfn_memslot(hva_start, memslot);
+ gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
+
+ for (; gfn < gfn_end; ++gfn) {
+ gpa_t gpa = gfn << PAGE_SHIFT;
+ handler(kvm, gpa, data);
+ }
+ }
+}
+
+static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
+{
+ stage2_clear_pte(kvm, gpa);
+}
+
+int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
+{
+ unsigned long end = hva + PAGE_SIZE;
+
+ if (!kvm->arch.pgd)
+ return 0;
+
+ trace_kvm_unmap_hva(hva);
+ handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL);
+ return 0;
+}
+
+int kvm_unmap_hva_range(struct kvm *kvm,
+ unsigned long start, unsigned long end)
+{
+ if (!kvm->arch.pgd)
+ return 0;
+
+ trace_kvm_unmap_hva_range(start, end);
+ handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
+ return 0;
+}
+
+static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data)
+{
+ pte_t *pte = (pte_t *)data;
+
+ stage2_set_pte(kvm, NULL, gpa, pte, false);
+}
+
+
+void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
+{
+ unsigned long end = hva + PAGE_SIZE;
+ pte_t stage2_pte;
+
+ if (!kvm->arch.pgd)
+ return;
+
+ trace_kvm_set_spte_hva(hva);
+ stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
+ handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
+}
+
+void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
+{
+ mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
+}
+
unsigned long kvm_mmu_get_httbr(void)
{
return virt_to_phys(hyp_pgd);
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index f8869c1..862b2cc 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -39,7 +39,53 @@ TRACE_EVENT(kvm_exit,
TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
);
+TRACE_EVENT(kvm_unmap_hva,
+ TP_PROTO(unsigned long hva),
+ TP_ARGS(hva),
+ TP_STRUCT__entry(
+ __field( unsigned long, hva )
+ ),
+
+ TP_fast_assign(
+ __entry->hva = hva;
+ ),
+
+ TP_printk("mmu notifier unmap hva: %#08lx", __entry->hva)
+);
+
+TRACE_EVENT(kvm_unmap_hva_range,
+ TP_PROTO(unsigned long start, unsigned long end),
+ TP_ARGS(start, end),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, start )
+ __field( unsigned long, end )
+ ),
+
+ TP_fast_assign(
+ __entry->start = start;
+ __entry->end = end;
+ ),
+
+ TP_printk("mmu notifier unmap range: %#08lx -- %#08lx",
+ __entry->start, __entry->end)
+);
+
+TRACE_EVENT(kvm_set_spte_hva,
+ TP_PROTO(unsigned long hva),
+ TP_ARGS(hva),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, hva )
+ ),
+
+ TP_fast_assign(
+ __entry->hva = hva;
+ ),
+
+ TP_printk("mmu notifier set pte hva: %#08lx", __entry->hva)
+);
#endif /* _TRACE_KVM_H */
^ permalink raw reply related [flat|nested] 17+ messages in thread* [kvmarm] [PATCH v3 06/14] KVM: ARM: Memory virtualization setup
2012-10-22 6:49 ` [PATCH v3 06/14] KVM: ARM: Memory virtualization setup Christoffer Dall
@ 2012-11-19 11:29 ` Sundaram, Senthilkumar
2012-11-19 14:42 ` Christoffer Dall
0 siblings, 1 reply; 17+ messages in thread
From: Sundaram, Senthilkumar @ 2012-11-19 11:29 UTC (permalink / raw)
To: linux-arm-kernel
What is the use of MMU Notifiers in the absence of Shadow Page Table?
Thanks
Senthil
> -----Original Message-----
> From: kvmarm-bounces at lists.cs.columbia.edu [mailto:kvmarm-
> bounces at lists.cs.columbia.edu] On Behalf Of Christoffer Dall
> Sent: Monday, October 22, 2012 12:20 PM
> To: kvm at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
> kvmarm at lists.cs.columbia.edu
> Cc: Marcelo Tosatti
> Subject: [kvmarm] [PATCH v3 06/14] KVM: ARM: Memory virtualization setup
>
> This commit introduces the framework for guest memory management
> through the use of 2nd stage translation. Each VM has a pointer to a level-1
> table (the pgd field in struct kvm_arch) which is used for the 2nd stage
> translations. Entries are added when handling guest faults (later patch) and
> the table itself can be allocated and freed through the following functions
> implemented in
> arch/arm/kvm/arm_mmu.c:
> - kvm_alloc_stage2_pgd(struct kvm *kvm);
> - kvm_free_stage2_pgd(struct kvm *kvm);
>
> Each entry in TLBs and caches are tagged with a VMID identifier in addition to
> ASIDs. The VMIDs are assigned consecutively to VMs in the order that VMs
> are executed, and caches and tlbs are invalidated when the VMID space has
> been used to allow for more than 255 simultaenously running guests.
>
> The 2nd stage pgd is allocated in kvm_arch_init_vm(). The table is freed in
> kvm_arch_destroy_vm(). Both functions are called from the main KVM code.
>
> We pre-allocate page table memory to be able to synchronize using a
> spinlock and be called under rcu_read_lock from the MMU notifiers. We
> steal the mmu_memory_cache implementation from x86 and adapt for our
> specific usage.
>
> We support MMU notifiers (thanks to Marc Zyngier) through
> kvm_unmap_hva and kvm_set_spte_hva.
>
> Finally, define kvm_phys_addr_ioremap() to map a device at a guest IPA,
> which is used by VGIC support to map the virtual CPU interface registers to
> the guest. This support is added by Marc Zyngier.
>
> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
> ---
> arch/arm/include/asm/kvm_asm.h | 2
> arch/arm/include/asm/kvm_host.h | 19 ++
> arch/arm/include/asm/kvm_mmu.h | 9 +
> arch/arm/kvm/Kconfig | 1
> arch/arm/kvm/arm.c | 37 ++++
> arch/arm/kvm/interrupts.S | 10 +
> arch/arm/kvm/mmu.c | 393
> +++++++++++++++++++++++++++++++++++++++
> arch/arm/kvm/trace.h | 46 +++++
> 8 files changed, 515 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/include/asm/kvm_asm.h
> b/arch/arm/include/asm/kvm_asm.h index 954bf7c..47a0e57 100644
> --- a/arch/arm/include/asm/kvm_asm.h
> +++ b/arch/arm/include/asm/kvm_asm.h
> @@ -57,6 +57,7 @@
> #define ARM_EXCEPTION_HVC 7
>
> #ifndef __ASSEMBLY__
> +struct kvm;
> struct kvm_vcpu;
>
> extern char __kvm_hyp_init[];
> @@ -71,6 +72,7 @@ extern char __kvm_hyp_code_start[]; extern char
> __kvm_hyp_code_end[];
>
> extern void __kvm_flush_vm_context(void);
> +extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
>
> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); #endif diff --git
> a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index 15d4c0b..68d1005 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -117,4 +117,23 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu
> *vcpu, u64 __user *indices); struct kvm_one_reg; int
> kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
> int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg
> *reg);
> +u64 kvm_call_hyp(void *hypfn, ...);
> +
> +#define KVM_ARCH_WANT_MMU_NOTIFIER
> +struct kvm;
> +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int
> +kvm_unmap_hva_range(struct kvm *kvm,
> + unsigned long start, unsigned long end); void
> +kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
> +
> +/* We do not have shadow page tables, hence the empty hooks */ static
> +inline int kvm_age_hva(struct kvm *kvm, unsigned long hva) {
> + return 0;
> +}
> +
> +static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
> +{
> + return 0;
> +}
> #endif /* __ARM_KVM_HOST_H__ */
> diff --git a/arch/arm/include/asm/kvm_mmu.h
> b/arch/arm/include/asm/kvm_mmu.h index 741ab8f..9bd0508 100644
> --- a/arch/arm/include/asm/kvm_mmu.h
> +++ b/arch/arm/include/asm/kvm_mmu.h
> @@ -33,6 +33,15 @@ int create_hyp_mappings(void *from, void *to); int
> create_hyp_io_mappings(void *from, void *to, phys_addr_t); void
> free_hyp_pmds(void);
>
> +int kvm_alloc_stage2_pgd(struct kvm *kvm); void
> +kvm_free_stage2_pgd(struct kvm *kvm); int
> kvm_phys_addr_ioremap(struct
> +kvm *kvm, phys_addr_t guest_ipa,
> + phys_addr_t pa, unsigned long size);
> +
> +int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run
> *run);
> +
> +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
> +
> unsigned long kvm_mmu_get_httbr(void);
> int kvm_mmu_init(void);
> void kvm_mmu_exit(void);
> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig index
> a07ddcc..47c5500 100644
> --- a/arch/arm/kvm/Kconfig
> +++ b/arch/arm/kvm/Kconfig
> @@ -36,6 +36,7 @@ config KVM_ARM_HOST
> depends on KVM
> depends on MMU
> depends on CPU_V7 && ARM_VIRT_EXT
> + select MMU_NOTIFIER
> ---help---
> Provides host support for ARM processors.
>
> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index
> 8e1ea2b..5ac3132 100644
> --- a/arch/arm/kvm/arm.c
> +++ b/arch/arm/kvm/arm.c
> @@ -81,12 +81,33 @@ void kvm_arch_sync_events(struct kvm *kvm) { }
>
> +/**
> + * kvm_arch_init_vm - initializes a VM data structure
> + * @kvm: pointer to the KVM struct
> + */
> int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) {
> + int ret = 0;
> +
> if (type)
> return -EINVAL;
>
> - return 0;
> + ret = kvm_alloc_stage2_pgd(kvm);
> + if (ret)
> + goto out_fail_alloc;
> +
> + ret = create_hyp_mappings(kvm, kvm + 1);
> + if (ret)
> + goto out_free_stage2_pgd;
> +
> + /* Mark the initial VMID generation invalid */
> + kvm->arch.vmid_gen = 0;
> +
> + return ret;
> +out_free_stage2_pgd:
> + kvm_free_stage2_pgd(kvm);
> +out_fail_alloc:
> + return ret;
> }
>
> int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) @@
> -104,10 +125,16 @@ int kvm_arch_create_memslot(struct
> kvm_memory_slot *slot, unsigned long npages)
> return 0;
> }
>
> +/**
> + * kvm_arch_destroy_vm - destroy the VM data structure
> + * @kvm: pointer to the KVM struct
> + */
> void kvm_arch_destroy_vm(struct kvm *kvm) {
> int i;
>
> + kvm_free_stage2_pgd(kvm);
> +
> for (i = 0; i < KVM_MAX_VCPUS; ++i) {
> if (kvm->vcpus[i]) {
> kvm_arch_vcpu_free(kvm->vcpus[i]);
> @@ -189,7 +216,13 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct
> kvm *kvm, unsigned int id)
> if (err)
> goto free_vcpu;
>
> + err = create_hyp_mappings(vcpu, vcpu + 1);
> + if (err)
> + goto vcpu_uninit;
> +
> return vcpu;
> +vcpu_uninit:
> + kvm_vcpu_uninit(vcpu);
> free_vcpu:
> kmem_cache_free(kvm_vcpu_cache, vcpu);
> out:
> @@ -198,6 +231,8 @@ out:
>
> void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) {
> + kvm_mmu_free_memory_caches(vcpu);
> + kmem_cache_free(kvm_vcpu_cache, vcpu);
> }
>
> void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) diff --git
> a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S index
> 98a67ca..1c83022 100644
> --- a/arch/arm/kvm/interrupts.S
> +++ b/arch/arm/kvm/interrupts.S
> @@ -33,7 +33,13 @@ __kvm_hyp_code_start:
>
> /**********************************************************
> **********
> * Flush per-VMID TLBs
> */
> +ENTRY(__kvm_tlb_flush_vmid)
> + bx lr
> +ENDPROC(__kvm_tlb_flush_vmid)
>
> +/*********************************************************
> ***********
> + * Flush TLBs and instruction caches of current CPU for all VMIDs */
> ENTRY(__kvm_flush_vm_context)
> bx lr
> ENDPROC(__kvm_flush_vm_context)
> @@ -41,10 +47,12 @@ ENDPROC(__kvm_flush_vm_context)
>
> /**********************************************************
> **********
> * Hypervisor world-switch code
> */
> -
> ENTRY(__kvm_vcpu_run)
> bx lr
>
> +ENTRY(kvm_call_hyp)
> + bx lr
> +
>
>
> /**********************************************************
> **********
> * Hypervisor exception vector and handlers diff --git
> a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 17c2bf5..f45be86
> 100644
> --- a/arch/arm/kvm/mmu.c
> +++ b/arch/arm/kvm/mmu.c
> @@ -23,11 +23,52 @@
> #include <asm/pgalloc.h>
> #include <asm/kvm_arm.h>
> #include <asm/kvm_mmu.h>
> +#include <asm/kvm_asm.h>
> #include <asm/mach/map.h>
> +#include <trace/events/kvm.h>
> +
> +#include "trace.h"
>
> static DEFINE_MUTEX(kvm_hyp_pgd_mutex); static pgd_t *hyp_pgd;
>
> +static void kvm_tlb_flush_vmid(struct kvm *kvm) {
> + kvm_call_hyp(__kvm_tlb_flush_vmid, kvm); }
> +
> +static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
> *cache,
> + int min, int max)
> +{
> + void *page;
> +
> + BUG_ON(max > KVM_NR_MEM_OBJS);
> + if (cache->nobjs >= min)
> + return 0;
> + while (cache->nobjs < max) {
> + page = (void *)__get_free_page(PGALLOC_GFP);
> + if (!page)
> + return -ENOMEM;
> + cache->objects[cache->nobjs++] = page;
> + }
> + return 0;
> +}
> +
> +static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
> *mc) {
> + while (mc->nobjs)
> + free_page((unsigned long)mc->objects[--mc->nobjs]); }
> +
> +static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
> *mc) {
> + void *p;
> +
> + BUG_ON(!mc || !mc->nobjs);
> + p = mc->objects[--mc->nobjs];
> + return p;
> +}
> +
> static void free_ptes(pmd_t *pmd, unsigned long addr) {
> pte_t *pte;
> @@ -201,11 +242,363 @@ int create_hyp_io_mappings(void *from, void *to,
> phys_addr_t addr)
> return __create_hyp_mappings(from, to, &pfn); }
>
> +/**
> + * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
> + * @kvm: The KVM struct pointer for the VM.
> + *
> + * Allocates the 1st level table only of size defined by PGD2_ORDER
> +(can
> + * support either full 40-bit input addresses or limited to 32-bit
> +input
> + * addresses). Clears the allocated pages.
> + *
> + * Note we don't need locking here as this is only called when the VM
> +is
> + * created, which can only be done once.
> + */
> +int kvm_alloc_stage2_pgd(struct kvm *kvm) {
> + pgd_t *pgd;
> +
> + if (kvm->arch.pgd != NULL) {
> + kvm_err("kvm_arch already initialized?\n");
> + return -EINVAL;
> + }
> +
> + pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, PGD2_ORDER);
> + if (!pgd)
> + return -ENOMEM;
> +
> + memset(pgd, 0, PTRS_PER_PGD2 * sizeof(pgd_t));
> + clean_dcache_area(pgd, PTRS_PER_PGD2 * sizeof(pgd_t));
> + kvm->arch.pgd = pgd;
> +
> + return 0;
> +}
> +
> +static void free_guest_pages(pte_t *pte, unsigned long addr) {
> + unsigned int i;
> + struct page *pte_page;
> +
> + pte_page = virt_to_page(pte);
> +
> + for (i = 0; i < PTRS_PER_PTE; i++) {
> + if (pte_present(*pte))
> + put_page(pte_page);
> + pte++;
> + }
> +
> + WARN_ON(page_count(pte_page) != 1);
> +}
> +
> +static void free_stage2_ptes(pmd_t *pmd, unsigned long addr) {
> + unsigned int i;
> + pte_t *pte;
> + struct page *pmd_page;
> +
> + pmd_page = virt_to_page(pmd);
> +
> + for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
> + BUG_ON(pmd_sect(*pmd));
> + if (!pmd_none(*pmd) && pmd_table(*pmd)) {
> + pte = pte_offset_kernel(pmd, addr);
> + free_guest_pages(pte, addr);
> + pte_free_kernel(NULL, pte);
> +
> + put_page(pmd_page);
> + }
> + pmd++;
> + }
> +
> + WARN_ON(page_count(pmd_page) != 1);
> +}
> +
> +/**
> + * kvm_free_stage2_pgd - free all stage-2 tables
> + * @kvm: The KVM struct pointer for the VM.
> + *
> + * Walks the level-1 page table pointed to by kvm->arch.pgd and frees
> +all
> + * underlying level-2 and level-3 tables before freeing the actual
> +level-1 table
> + * and setting the struct pointer to NULL.
> + *
> + * Note we don't need locking here as this is only called when the VM
> +is
> + * destroyed, which can only be done once.
> + */
> +void kvm_free_stage2_pgd(struct kvm *kvm) {
> + pgd_t *pgd;
> + pud_t *pud;
> + pmd_t *pmd;
> + unsigned long long i, addr;
> + struct page *pud_page;
> +
> + if (kvm->arch.pgd == NULL)
> + return;
> +
> + /*
> + * We do this slightly different than other places, since we need more
> + * than 32 bits and for instance pgd_addr_end converts to unsigned
> long.
> + */
> + addr = 0;
> + for (i = 0; i < PTRS_PER_PGD2; i++) {
> + addr = i * (unsigned long long)PGDIR_SIZE;
> + pgd = kvm->arch.pgd + i;
> + pud = pud_offset(pgd, addr);
> + pud_page = virt_to_page(pud);
> +
> + if (pud_none(*pud))
> + continue;
> +
> + BUG_ON(pud_bad(*pud));
> +
> + pmd = pmd_offset(pud, addr);
> + free_stage2_ptes(pmd, addr);
> + pmd_free(NULL, pmd);
> + put_page(pud_page);
> + }
> +
> + WARN_ON(page_count(pud_page) != 1);
> + free_pages((unsigned long)kvm->arch.pgd, PGD2_ORDER);
> + kvm->arch.pgd = NULL;
> +}
> +
> +/**
> + * stage2_clear_pte -- Clear a stage-2 PTE.
> + * @kvm: The VM pointer
> + * @addr: The physical address of the PTE
> + *
> + * Clear a stage-2 PTE, lowering the various ref-counts. Also takes
> + * care of invalidating the TLBs. Must be called while holding
> + * mmu_lock, otherwise another faulting VCPU may come in and mess
> + * things behind our back.
> + */
> +static void stage2_clear_pte(struct kvm *kvm, phys_addr_t addr) {
> + pgd_t *pgd;
> + pud_t *pud;
> + pmd_t *pmd;
> + pte_t *pte;
> + struct page *page;
> +
> + pgd = kvm->arch.pgd + pgd_index(addr);
> + pud = pud_offset(pgd, addr);
> + if (pud_none(*pud))
> + return;
> +
> + pmd = pmd_offset(pud, addr);
> + if (pmd_none(*pmd))
> + return;
> +
> + pte = pte_offset_kernel(pmd, addr);
> + set_pte_ext(pte, __pte(0), 0);
> +
> + page = virt_to_page(pte);
> + put_page(page);
> + if (page_count(page) != 1) {
> + kvm_tlb_flush_vmid(kvm);
> + return;
> + }
> +
> + /* Need to remove pte page */
> + pmd_clear(pmd);
> + pte_free_kernel(NULL, (pte_t *)((unsigned long)pte &
> PAGE_MASK));
> +
> + page = virt_to_page(pmd);
> + put_page(page);
> + if (page_count(page) != 1) {
> + kvm_tlb_flush_vmid(kvm);
> + return;
> + }
> +
> + pud_clear(pud);
> + pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
> +
> + page = virt_to_page(pud);
> + put_page(page);
> + kvm_tlb_flush_vmid(kvm);
> +}
> +
> +static int stage2_set_pte(struct kvm *kvm, struct
> kvm_mmu_memory_cache *cache,
> + phys_addr_t addr, const pte_t *new_pte, bool
> iomap) {
> + pgd_t *pgd;
> + pud_t *pud;
> + pmd_t *pmd;
> + pte_t *pte, old_pte;
> +
> + /* Create 2nd stage page table mapping - Level 1 */
> + pgd = kvm->arch.pgd + pgd_index(addr);
> + pud = pud_offset(pgd, addr);
> + if (pud_none(*pud)) {
> + if (!cache)
> + return 0; /* ignore calls from kvm_set_spte_hva */
> + pmd = mmu_memory_cache_alloc(cache);
> + pud_populate(NULL, pud, pmd);
> + pmd += pmd_index(addr);
> + get_page(virt_to_page(pud));
> + } else
> + pmd = pmd_offset(pud, addr);
> +
> + /* Create 2nd stage page table mapping - Level 2 */
> + if (pmd_none(*pmd)) {
> + if (!cache)
> + return 0; /* ignore calls from kvm_set_spte_hva */
> + pte = mmu_memory_cache_alloc(cache);
> + clean_pte_table(pte);
> + pmd_populate_kernel(NULL, pmd, pte);
> + pte += pte_index(addr);
> + get_page(virt_to_page(pmd));
> + } else
> + pte = pte_offset_kernel(pmd, addr);
> +
> + if (iomap && pte_present(*pte))
> + return -EFAULT;
> +
> + /* Create 2nd stage page table mapping - Level 3 */
> + old_pte = *pte;
> + set_pte_ext(pte, *new_pte, 0);
> + if (pte_present(old_pte))
> + kvm_tlb_flush_vmid(kvm);
> + else
> + get_page(virt_to_page(pte));
> +
> + return 0;
> +}
> +
> +/**
> + * kvm_phys_addr_ioremap - map a device range to guest IPA
> + *
> + * @kvm: The KVM pointer
> + * @guest_ipa: The IPA at which to insert the mapping
> + * @pa: The physical address of the device
> + * @size: The size of the mapping
> + */
> +int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
> + phys_addr_t pa, unsigned long size) {
> + phys_addr_t addr, end;
> + int ret = 0;
> + unsigned long pfn;
> + struct kvm_mmu_memory_cache cache = { 0, };
> +
> + end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
> + pfn = __phys_to_pfn(pa);
> +
> + for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
> + pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE |
> L_PTE_S2_RDWR);
> +
> + ret = mmu_topup_memory_cache(&cache, 2, 2);
> + if (ret)
> + goto out;
> + spin_lock(&kvm->mmu_lock);
> + ret = stage2_set_pte(kvm, &cache, addr, &pte, true);
> + spin_unlock(&kvm->mmu_lock);
> + if (ret)
> + goto out;
> +
> + pfn++;
> + }
> +
> +out:
> + mmu_free_memory_cache(&cache);
> + return ret;
> +}
> +
> int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
> {
> return -EINVAL;
> }
>
> +static void handle_hva_to_gpa(struct kvm *kvm,
> + unsigned long start,
> + unsigned long end,
> + void (*handler)(struct kvm *kvm,
> + gpa_t gpa, void *data),
> + void *data)
> +{
> + struct kvm_memslots *slots;
> + struct kvm_memory_slot *memslot;
> +
> + slots = kvm_memslots(kvm);
> +
> + /* we only care about the pages that the guest sees */
> + kvm_for_each_memslot(memslot, slots) {
> + unsigned long hva_start, hva_end;
> + gfn_t gfn, gfn_end;
> +
> + hva_start = max(start, memslot->userspace_addr);
> + hva_end = min(end, memslot->userspace_addr +
> + (memslot->npages << PAGE_SHIFT));
> + if (hva_start >= hva_end)
> + continue;
> +
> + /*
> + * {gfn(page) | page intersects with [hva_start, hva_end)} =
> + * {gfn_start, gfn_start+1, ..., gfn_end-1}.
> + */
> + gfn = hva_to_gfn_memslot(hva_start, memslot);
> + gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1,
> memslot);
> +
> + for (; gfn < gfn_end; ++gfn) {
> + gpa_t gpa = gfn << PAGE_SHIFT;
> + handler(kvm, gpa, data);
> + }
> + }
> +}
> +
> +static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void
> +*data) {
> + stage2_clear_pte(kvm, gpa);
> +}
> +
> +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) {
> + unsigned long end = hva + PAGE_SIZE;
> +
> + if (!kvm->arch.pgd)
> + return 0;
> +
> + trace_kvm_unmap_hva(hva);
> + handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler,
> NULL);
> + return 0;
> +}
> +
> +int kvm_unmap_hva_range(struct kvm *kvm,
> + unsigned long start, unsigned long end) {
> + if (!kvm->arch.pgd)
> + return 0;
> +
> + trace_kvm_unmap_hva_range(start, end);
> + handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler,
> NULL);
> + return 0;
> +}
> +
> +static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void
> +*data) {
> + pte_t *pte = (pte_t *)data;
> +
> + stage2_set_pte(kvm, NULL, gpa, pte, false); }
> +
> +
> +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) {
> + unsigned long end = hva + PAGE_SIZE;
> + pte_t stage2_pte;
> +
> + if (!kvm->arch.pgd)
> + return;
> +
> + trace_kvm_set_spte_hva(hva);
> + stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
> + handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler,
> &stage2_pte);
> +}
> +
> +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) {
> + mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
> +}
> +
> unsigned long kvm_mmu_get_httbr(void)
> {
> return virt_to_phys(hyp_pgd);
> diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index
> f8869c1..862b2cc 100644
> --- a/arch/arm/kvm/trace.h
> +++ b/arch/arm/kvm/trace.h
> @@ -39,7 +39,53 @@ TRACE_EVENT(kvm_exit,
> TP_printk("PC: 0x%08lx", __entry->vcpu_pc) );
>
> +TRACE_EVENT(kvm_unmap_hva,
> + TP_PROTO(unsigned long hva),
> + TP_ARGS(hva),
>
> + TP_STRUCT__entry(
> + __field( unsigned long, hva )
> + ),
> +
> + TP_fast_assign(
> + __entry->hva = hva;
> + ),
> +
> + TP_printk("mmu notifier unmap hva: %#08lx", __entry->hva) );
> +
> +TRACE_EVENT(kvm_unmap_hva_range,
> + TP_PROTO(unsigned long start, unsigned long end),
> + TP_ARGS(start, end),
> +
> + TP_STRUCT__entry(
> + __field( unsigned long, start )
> + __field( unsigned long, end )
> + ),
> +
> + TP_fast_assign(
> + __entry->start = start;
> + __entry->end = end;
> + ),
> +
> + TP_printk("mmu notifier unmap range: %#08lx -- %#08lx",
> + __entry->start, __entry->end)
> +);
> +
> +TRACE_EVENT(kvm_set_spte_hva,
> + TP_PROTO(unsigned long hva),
> + TP_ARGS(hva),
> +
> + TP_STRUCT__entry(
> + __field( unsigned long, hva )
> + ),
> +
> + TP_fast_assign(
> + __entry->hva = hva;
> + ),
> +
> + TP_printk("mmu notifier set pte hva: %#08lx", __entry->hva) );
>
> #endif /* _TRACE_KVM_H */
>
>
> _______________________________________________
> kvmarm mailing list
> kvmarm at lists.cs.columbia.edu
> https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
^ permalink raw reply [flat|nested] 17+ messages in thread* [kvmarm] [PATCH v3 06/14] KVM: ARM: Memory virtualization setup
2012-11-19 11:29 ` [kvmarm] " Sundaram, Senthilkumar
@ 2012-11-19 14:42 ` Christoffer Dall
0 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-11-19 14:42 UTC (permalink / raw)
To: linux-arm-kernel
On Mon, Nov 19, 2012 at 6:29 AM, Sundaram, Senthilkumar
<ssundara@qti.qualcomm.com> wrote:
> What is the use of MMU Notifiers in the absence of Shadow Page Table?
>
> Thanks
> Senthil
MMU notifiers are used to manage the stage-2 page tables in the event
of swapping or KSM. Please don't top-top post to this list.
-Christoffer
>> -----Original Message-----
>> From: kvmarm-bounces at lists.cs.columbia.edu [mailto:kvmarm-
>> bounces at lists.cs.columbia.edu] On Behalf Of Christoffer Dall
>> Sent: Monday, October 22, 2012 12:20 PM
>> To: kvm at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
>> kvmarm at lists.cs.columbia.edu
>> Cc: Marcelo Tosatti
>> Subject: [kvmarm] [PATCH v3 06/14] KVM: ARM: Memory virtualization setup
>>
>> This commit introduces the framework for guest memory management
>> through the use of 2nd stage translation. Each VM has a pointer to a level-1
>> table (the pgd field in struct kvm_arch) which is used for the 2nd stage
>> translations. Entries are added when handling guest faults (later patch) and
>> the table itself can be allocated and freed through the following functions
>> implemented in
>> arch/arm/kvm/arm_mmu.c:
>> - kvm_alloc_stage2_pgd(struct kvm *kvm);
>> - kvm_free_stage2_pgd(struct kvm *kvm);
>>
>> Each entry in TLBs and caches are tagged with a VMID identifier in addition to
>> ASIDs. The VMIDs are assigned consecutively to VMs in the order that VMs
>> are executed, and caches and tlbs are invalidated when the VMID space has
>> been used to allow for more than 255 simultaenously running guests.
>>
>> The 2nd stage pgd is allocated in kvm_arch_init_vm(). The table is freed in
>> kvm_arch_destroy_vm(). Both functions are called from the main KVM code.
>>
>> We pre-allocate page table memory to be able to synchronize using a
>> spinlock and be called under rcu_read_lock from the MMU notifiers. We
>> steal the mmu_memory_cache implementation from x86 and adapt for our
>> specific usage.
>>
>> We support MMU notifiers (thanks to Marc Zyngier) through
>> kvm_unmap_hva and kvm_set_spte_hva.
>>
>> Finally, define kvm_phys_addr_ioremap() to map a device at a guest IPA,
>> which is used by VGIC support to map the virtual CPU interface registers to
>> the guest. This support is added by Marc Zyngier.
>>
>> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
>> ---
>> arch/arm/include/asm/kvm_asm.h | 2
>> arch/arm/include/asm/kvm_host.h | 19 ++
>> arch/arm/include/asm/kvm_mmu.h | 9 +
>> arch/arm/kvm/Kconfig | 1
>> arch/arm/kvm/arm.c | 37 ++++
>> arch/arm/kvm/interrupts.S | 10 +
>> arch/arm/kvm/mmu.c | 393
>> +++++++++++++++++++++++++++++++++++++++
>> arch/arm/kvm/trace.h | 46 +++++
>> 8 files changed, 515 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/kvm_asm.h
>> b/arch/arm/include/asm/kvm_asm.h index 954bf7c..47a0e57 100644
>> --- a/arch/arm/include/asm/kvm_asm.h
>> +++ b/arch/arm/include/asm/kvm_asm.h
>> @@ -57,6 +57,7 @@
>> #define ARM_EXCEPTION_HVC 7
>>
>> #ifndef __ASSEMBLY__
>> +struct kvm;
>> struct kvm_vcpu;
>>
>> extern char __kvm_hyp_init[];
>> @@ -71,6 +72,7 @@ extern char __kvm_hyp_code_start[]; extern char
>> __kvm_hyp_code_end[];
>>
>> extern void __kvm_flush_vm_context(void);
>> +extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
>>
>> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); #endif diff --git
>> a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
>> index 15d4c0b..68d1005 100644
>> --- a/arch/arm/include/asm/kvm_host.h
>> +++ b/arch/arm/include/asm/kvm_host.h
>> @@ -117,4 +117,23 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu
>> *vcpu, u64 __user *indices); struct kvm_one_reg; int
>> kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
>> int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg
>> *reg);
>> +u64 kvm_call_hyp(void *hypfn, ...);
>> +
>> +#define KVM_ARCH_WANT_MMU_NOTIFIER
>> +struct kvm;
>> +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva); int
>> +kvm_unmap_hva_range(struct kvm *kvm,
>> + unsigned long start, unsigned long end); void
>> +kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
>> +
>> +/* We do not have shadow page tables, hence the empty hooks */ static
>> +inline int kvm_age_hva(struct kvm *kvm, unsigned long hva) {
>> + return 0;
>> +}
>> +
>> +static inline int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
>> +{
>> + return 0;
>> +}
>> #endif /* __ARM_KVM_HOST_H__ */
>> diff --git a/arch/arm/include/asm/kvm_mmu.h
>> b/arch/arm/include/asm/kvm_mmu.h index 741ab8f..9bd0508 100644
>> --- a/arch/arm/include/asm/kvm_mmu.h
>> +++ b/arch/arm/include/asm/kvm_mmu.h
>> @@ -33,6 +33,15 @@ int create_hyp_mappings(void *from, void *to); int
>> create_hyp_io_mappings(void *from, void *to, phys_addr_t); void
>> free_hyp_pmds(void);
>>
>> +int kvm_alloc_stage2_pgd(struct kvm *kvm); void
>> +kvm_free_stage2_pgd(struct kvm *kvm); int
>> kvm_phys_addr_ioremap(struct
>> +kvm *kvm, phys_addr_t guest_ipa,
>> + phys_addr_t pa, unsigned long size);
>> +
>> +int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run
>> *run);
>> +
>> +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
>> +
>> unsigned long kvm_mmu_get_httbr(void);
>> int kvm_mmu_init(void);
>> void kvm_mmu_exit(void);
>> diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig index
>> a07ddcc..47c5500 100644
>> --- a/arch/arm/kvm/Kconfig
>> +++ b/arch/arm/kvm/Kconfig
>> @@ -36,6 +36,7 @@ config KVM_ARM_HOST
>> depends on KVM
>> depends on MMU
>> depends on CPU_V7 && ARM_VIRT_EXT
>> + select MMU_NOTIFIER
>> ---help---
>> Provides host support for ARM processors.
>>
>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index
>> 8e1ea2b..5ac3132 100644
>> --- a/arch/arm/kvm/arm.c
>> +++ b/arch/arm/kvm/arm.c
>> @@ -81,12 +81,33 @@ void kvm_arch_sync_events(struct kvm *kvm) { }
>>
>> +/**
>> + * kvm_arch_init_vm - initializes a VM data structure
>> + * @kvm: pointer to the KVM struct
>> + */
>> int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) {
>> + int ret = 0;
>> +
>> if (type)
>> return -EINVAL;
>>
>> - return 0;
>> + ret = kvm_alloc_stage2_pgd(kvm);
>> + if (ret)
>> + goto out_fail_alloc;
>> +
>> + ret = create_hyp_mappings(kvm, kvm + 1);
>> + if (ret)
>> + goto out_free_stage2_pgd;
>> +
>> + /* Mark the initial VMID generation invalid */
>> + kvm->arch.vmid_gen = 0;
>> +
>> + return ret;
>> +out_free_stage2_pgd:
>> + kvm_free_stage2_pgd(kvm);
>> +out_fail_alloc:
>> + return ret;
>> }
>>
>> int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) @@
>> -104,10 +125,16 @@ int kvm_arch_create_memslot(struct
>> kvm_memory_slot *slot, unsigned long npages)
>> return 0;
>> }
>>
>> +/**
>> + * kvm_arch_destroy_vm - destroy the VM data structure
>> + * @kvm: pointer to the KVM struct
>> + */
>> void kvm_arch_destroy_vm(struct kvm *kvm) {
>> int i;
>>
>> + kvm_free_stage2_pgd(kvm);
>> +
>> for (i = 0; i < KVM_MAX_VCPUS; ++i) {
>> if (kvm->vcpus[i]) {
>> kvm_arch_vcpu_free(kvm->vcpus[i]);
>> @@ -189,7 +216,13 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct
>> kvm *kvm, unsigned int id)
>> if (err)
>> goto free_vcpu;
>>
>> + err = create_hyp_mappings(vcpu, vcpu + 1);
>> + if (err)
>> + goto vcpu_uninit;
>> +
>> return vcpu;
>> +vcpu_uninit:
>> + kvm_vcpu_uninit(vcpu);
>> free_vcpu:
>> kmem_cache_free(kvm_vcpu_cache, vcpu);
>> out:
>> @@ -198,6 +231,8 @@ out:
>>
>> void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) {
>> + kvm_mmu_free_memory_caches(vcpu);
>> + kmem_cache_free(kvm_vcpu_cache, vcpu);
>> }
>>
>> void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) diff --git
>> a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S index
>> 98a67ca..1c83022 100644
>> --- a/arch/arm/kvm/interrupts.S
>> +++ b/arch/arm/kvm/interrupts.S
>> @@ -33,7 +33,13 @@ __kvm_hyp_code_start:
>>
>> /**********************************************************
>> **********
>> * Flush per-VMID TLBs
>> */
>> +ENTRY(__kvm_tlb_flush_vmid)
>> + bx lr
>> +ENDPROC(__kvm_tlb_flush_vmid)
>>
>> +/*********************************************************
>> ***********
>> + * Flush TLBs and instruction caches of current CPU for all VMIDs */
>> ENTRY(__kvm_flush_vm_context)
>> bx lr
>> ENDPROC(__kvm_flush_vm_context)
>> @@ -41,10 +47,12 @@ ENDPROC(__kvm_flush_vm_context)
>>
>> /**********************************************************
>> **********
>> * Hypervisor world-switch code
>> */
>> -
>> ENTRY(__kvm_vcpu_run)
>> bx lr
>>
>> +ENTRY(kvm_call_hyp)
>> + bx lr
>> +
>>
>>
>> /**********************************************************
>> **********
>> * Hypervisor exception vector and handlers diff --git
>> a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 17c2bf5..f45be86
>> 100644
>> --- a/arch/arm/kvm/mmu.c
>> +++ b/arch/arm/kvm/mmu.c
>> @@ -23,11 +23,52 @@
>> #include <asm/pgalloc.h>
>> #include <asm/kvm_arm.h>
>> #include <asm/kvm_mmu.h>
>> +#include <asm/kvm_asm.h>
>> #include <asm/mach/map.h>
>> +#include <trace/events/kvm.h>
>> +
>> +#include "trace.h"
>>
>> static DEFINE_MUTEX(kvm_hyp_pgd_mutex); static pgd_t *hyp_pgd;
>>
>> +static void kvm_tlb_flush_vmid(struct kvm *kvm) {
>> + kvm_call_hyp(__kvm_tlb_flush_vmid, kvm); }
>> +
>> +static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
>> *cache,
>> + int min, int max)
>> +{
>> + void *page;
>> +
>> + BUG_ON(max > KVM_NR_MEM_OBJS);
>> + if (cache->nobjs >= min)
>> + return 0;
>> + while (cache->nobjs < max) {
>> + page = (void *)__get_free_page(PGALLOC_GFP);
>> + if (!page)
>> + return -ENOMEM;
>> + cache->objects[cache->nobjs++] = page;
>> + }
>> + return 0;
>> +}
>> +
>> +static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
>> *mc) {
>> + while (mc->nobjs)
>> + free_page((unsigned long)mc->objects[--mc->nobjs]); }
>> +
>> +static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
>> *mc) {
>> + void *p;
>> +
>> + BUG_ON(!mc || !mc->nobjs);
>> + p = mc->objects[--mc->nobjs];
>> + return p;
>> +}
>> +
>> static void free_ptes(pmd_t *pmd, unsigned long addr) {
>> pte_t *pte;
>> @@ -201,11 +242,363 @@ int create_hyp_io_mappings(void *from, void *to,
>> phys_addr_t addr)
>> return __create_hyp_mappings(from, to, &pfn); }
>>
>> +/**
>> + * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
>> + * @kvm: The KVM struct pointer for the VM.
>> + *
>> + * Allocates the 1st level table only of size defined by PGD2_ORDER
>> +(can
>> + * support either full 40-bit input addresses or limited to 32-bit
>> +input
>> + * addresses). Clears the allocated pages.
>> + *
>> + * Note we don't need locking here as this is only called when the VM
>> +is
>> + * created, which can only be done once.
>> + */
>> +int kvm_alloc_stage2_pgd(struct kvm *kvm) {
>> + pgd_t *pgd;
>> +
>> + if (kvm->arch.pgd != NULL) {
>> + kvm_err("kvm_arch already initialized?\n");
>> + return -EINVAL;
>> + }
>> +
>> + pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, PGD2_ORDER);
>> + if (!pgd)
>> + return -ENOMEM;
>> +
>> + memset(pgd, 0, PTRS_PER_PGD2 * sizeof(pgd_t));
>> + clean_dcache_area(pgd, PTRS_PER_PGD2 * sizeof(pgd_t));
>> + kvm->arch.pgd = pgd;
>> +
>> + return 0;
>> +}
>> +
>> +static void free_guest_pages(pte_t *pte, unsigned long addr) {
>> + unsigned int i;
>> + struct page *pte_page;
>> +
>> + pte_page = virt_to_page(pte);
>> +
>> + for (i = 0; i < PTRS_PER_PTE; i++) {
>> + if (pte_present(*pte))
>> + put_page(pte_page);
>> + pte++;
>> + }
>> +
>> + WARN_ON(page_count(pte_page) != 1);
>> +}
>> +
>> +static void free_stage2_ptes(pmd_t *pmd, unsigned long addr) {
>> + unsigned int i;
>> + pte_t *pte;
>> + struct page *pmd_page;
>> +
>> + pmd_page = virt_to_page(pmd);
>> +
>> + for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
>> + BUG_ON(pmd_sect(*pmd));
>> + if (!pmd_none(*pmd) && pmd_table(*pmd)) {
>> + pte = pte_offset_kernel(pmd, addr);
>> + free_guest_pages(pte, addr);
>> + pte_free_kernel(NULL, pte);
>> +
>> + put_page(pmd_page);
>> + }
>> + pmd++;
>> + }
>> +
>> + WARN_ON(page_count(pmd_page) != 1);
>> +}
>> +
>> +/**
>> + * kvm_free_stage2_pgd - free all stage-2 tables
>> + * @kvm: The KVM struct pointer for the VM.
>> + *
>> + * Walks the level-1 page table pointed to by kvm->arch.pgd and frees
>> +all
>> + * underlying level-2 and level-3 tables before freeing the actual
>> +level-1 table
>> + * and setting the struct pointer to NULL.
>> + *
>> + * Note we don't need locking here as this is only called when the VM
>> +is
>> + * destroyed, which can only be done once.
>> + */
>> +void kvm_free_stage2_pgd(struct kvm *kvm) {
>> + pgd_t *pgd;
>> + pud_t *pud;
>> + pmd_t *pmd;
>> + unsigned long long i, addr;
>> + struct page *pud_page;
>> +
>> + if (kvm->arch.pgd == NULL)
>> + return;
>> +
>> + /*
>> + * We do this slightly different than other places, since we need more
>> + * than 32 bits and for instance pgd_addr_end converts to unsigned
>> long.
>> + */
>> + addr = 0;
>> + for (i = 0; i < PTRS_PER_PGD2; i++) {
>> + addr = i * (unsigned long long)PGDIR_SIZE;
>> + pgd = kvm->arch.pgd + i;
>> + pud = pud_offset(pgd, addr);
>> + pud_page = virt_to_page(pud);
>> +
>> + if (pud_none(*pud))
>> + continue;
>> +
>> + BUG_ON(pud_bad(*pud));
>> +
>> + pmd = pmd_offset(pud, addr);
>> + free_stage2_ptes(pmd, addr);
>> + pmd_free(NULL, pmd);
>> + put_page(pud_page);
>> + }
>> +
>> + WARN_ON(page_count(pud_page) != 1);
>> + free_pages((unsigned long)kvm->arch.pgd, PGD2_ORDER);
>> + kvm->arch.pgd = NULL;
>> +}
>> +
>> +/**
>> + * stage2_clear_pte -- Clear a stage-2 PTE.
>> + * @kvm: The VM pointer
>> + * @addr: The physical address of the PTE
>> + *
>> + * Clear a stage-2 PTE, lowering the various ref-counts. Also takes
>> + * care of invalidating the TLBs. Must be called while holding
>> + * mmu_lock, otherwise another faulting VCPU may come in and mess
>> + * things behind our back.
>> + */
>> +static void stage2_clear_pte(struct kvm *kvm, phys_addr_t addr) {
>> + pgd_t *pgd;
>> + pud_t *pud;
>> + pmd_t *pmd;
>> + pte_t *pte;
>> + struct page *page;
>> +
>> + pgd = kvm->arch.pgd + pgd_index(addr);
>> + pud = pud_offset(pgd, addr);
>> + if (pud_none(*pud))
>> + return;
>> +
>> + pmd = pmd_offset(pud, addr);
>> + if (pmd_none(*pmd))
>> + return;
>> +
>> + pte = pte_offset_kernel(pmd, addr);
>> + set_pte_ext(pte, __pte(0), 0);
>> +
>> + page = virt_to_page(pte);
>> + put_page(page);
>> + if (page_count(page) != 1) {
>> + kvm_tlb_flush_vmid(kvm);
>> + return;
>> + }
>> +
>> + /* Need to remove pte page */
>> + pmd_clear(pmd);
>> + pte_free_kernel(NULL, (pte_t *)((unsigned long)pte &
>> PAGE_MASK));
>> +
>> + page = virt_to_page(pmd);
>> + put_page(page);
>> + if (page_count(page) != 1) {
>> + kvm_tlb_flush_vmid(kvm);
>> + return;
>> + }
>> +
>> + pud_clear(pud);
>> + pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
>> +
>> + page = virt_to_page(pud);
>> + put_page(page);
>> + kvm_tlb_flush_vmid(kvm);
>> +}
>> +
>> +static int stage2_set_pte(struct kvm *kvm, struct
>> kvm_mmu_memory_cache *cache,
>> + phys_addr_t addr, const pte_t *new_pte, bool
>> iomap) {
>> + pgd_t *pgd;
>> + pud_t *pud;
>> + pmd_t *pmd;
>> + pte_t *pte, old_pte;
>> +
>> + /* Create 2nd stage page table mapping - Level 1 */
>> + pgd = kvm->arch.pgd + pgd_index(addr);
>> + pud = pud_offset(pgd, addr);
>> + if (pud_none(*pud)) {
>> + if (!cache)
>> + return 0; /* ignore calls from kvm_set_spte_hva */
>> + pmd = mmu_memory_cache_alloc(cache);
>> + pud_populate(NULL, pud, pmd);
>> + pmd += pmd_index(addr);
>> + get_page(virt_to_page(pud));
>> + } else
>> + pmd = pmd_offset(pud, addr);
>> +
>> + /* Create 2nd stage page table mapping - Level 2 */
>> + if (pmd_none(*pmd)) {
>> + if (!cache)
>> + return 0; /* ignore calls from kvm_set_spte_hva */
>> + pte = mmu_memory_cache_alloc(cache);
>> + clean_pte_table(pte);
>> + pmd_populate_kernel(NULL, pmd, pte);
>> + pte += pte_index(addr);
>> + get_page(virt_to_page(pmd));
>> + } else
>> + pte = pte_offset_kernel(pmd, addr);
>> +
>> + if (iomap && pte_present(*pte))
>> + return -EFAULT;
>> +
>> + /* Create 2nd stage page table mapping - Level 3 */
>> + old_pte = *pte;
>> + set_pte_ext(pte, *new_pte, 0);
>> + if (pte_present(old_pte))
>> + kvm_tlb_flush_vmid(kvm);
>> + else
>> + get_page(virt_to_page(pte));
>> +
>> + return 0;
>> +}
>> +
>> +/**
>> + * kvm_phys_addr_ioremap - map a device range to guest IPA
>> + *
>> + * @kvm: The KVM pointer
>> + * @guest_ipa: The IPA at which to insert the mapping
>> + * @pa: The physical address of the device
>> + * @size: The size of the mapping
>> + */
>> +int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
>> + phys_addr_t pa, unsigned long size) {
>> + phys_addr_t addr, end;
>> + int ret = 0;
>> + unsigned long pfn;
>> + struct kvm_mmu_memory_cache cache = { 0, };
>> +
>> + end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
>> + pfn = __phys_to_pfn(pa);
>> +
>> + for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
>> + pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE |
>> L_PTE_S2_RDWR);
>> +
>> + ret = mmu_topup_memory_cache(&cache, 2, 2);
>> + if (ret)
>> + goto out;
>> + spin_lock(&kvm->mmu_lock);
>> + ret = stage2_set_pte(kvm, &cache, addr, &pte, true);
>> + spin_unlock(&kvm->mmu_lock);
>> + if (ret)
>> + goto out;
>> +
>> + pfn++;
>> + }
>> +
>> +out:
>> + mmu_free_memory_cache(&cache);
>> + return ret;
>> +}
>> +
>> int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
>> {
>> return -EINVAL;
>> }
>>
>> +static void handle_hva_to_gpa(struct kvm *kvm,
>> + unsigned long start,
>> + unsigned long end,
>> + void (*handler)(struct kvm *kvm,
>> + gpa_t gpa, void *data),
>> + void *data)
>> +{
>> + struct kvm_memslots *slots;
>> + struct kvm_memory_slot *memslot;
>> +
>> + slots = kvm_memslots(kvm);
>> +
>> + /* we only care about the pages that the guest sees */
>> + kvm_for_each_memslot(memslot, slots) {
>> + unsigned long hva_start, hva_end;
>> + gfn_t gfn, gfn_end;
>> +
>> + hva_start = max(start, memslot->userspace_addr);
>> + hva_end = min(end, memslot->userspace_addr +
>> + (memslot->npages << PAGE_SHIFT));
>> + if (hva_start >= hva_end)
>> + continue;
>> +
>> + /*
>> + * {gfn(page) | page intersects with [hva_start, hva_end)} =
>> + * {gfn_start, gfn_start+1, ..., gfn_end-1}.
>> + */
>> + gfn = hva_to_gfn_memslot(hva_start, memslot);
>> + gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1,
>> memslot);
>> +
>> + for (; gfn < gfn_end; ++gfn) {
>> + gpa_t gpa = gfn << PAGE_SHIFT;
>> + handler(kvm, gpa, data);
>> + }
>> + }
>> +}
>> +
>> +static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void
>> +*data) {
>> + stage2_clear_pte(kvm, gpa);
>> +}
>> +
>> +int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) {
>> + unsigned long end = hva + PAGE_SIZE;
>> +
>> + if (!kvm->arch.pgd)
>> + return 0;
>> +
>> + trace_kvm_unmap_hva(hva);
>> + handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler,
>> NULL);
>> + return 0;
>> +}
>> +
>> +int kvm_unmap_hva_range(struct kvm *kvm,
>> + unsigned long start, unsigned long end) {
>> + if (!kvm->arch.pgd)
>> + return 0;
>> +
>> + trace_kvm_unmap_hva_range(start, end);
>> + handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler,
>> NULL);
>> + return 0;
>> +}
>> +
>> +static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void
>> +*data) {
>> + pte_t *pte = (pte_t *)data;
>> +
>> + stage2_set_pte(kvm, NULL, gpa, pte, false); }
>> +
>> +
>> +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) {
>> + unsigned long end = hva + PAGE_SIZE;
>> + pte_t stage2_pte;
>> +
>> + if (!kvm->arch.pgd)
>> + return;
>> +
>> + trace_kvm_set_spte_hva(hva);
>> + stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
>> + handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler,
>> &stage2_pte);
>> +}
>> +
>> +void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) {
>> + mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
>> +}
>> +
>> unsigned long kvm_mmu_get_httbr(void)
>> {
>> return virt_to_phys(hyp_pgd);
>> diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index
>> f8869c1..862b2cc 100644
>> --- a/arch/arm/kvm/trace.h
>> +++ b/arch/arm/kvm/trace.h
>> @@ -39,7 +39,53 @@ TRACE_EVENT(kvm_exit,
>> TP_printk("PC: 0x%08lx", __entry->vcpu_pc) );
>>
>> +TRACE_EVENT(kvm_unmap_hva,
>> + TP_PROTO(unsigned long hva),
>> + TP_ARGS(hva),
>>
>> + TP_STRUCT__entry(
>> + __field( unsigned long, hva )
>> + ),
>> +
>> + TP_fast_assign(
>> + __entry->hva = hva;
>> + ),
>> +
>> + TP_printk("mmu notifier unmap hva: %#08lx", __entry->hva) );
>> +
>> +TRACE_EVENT(kvm_unmap_hva_range,
>> + TP_PROTO(unsigned long start, unsigned long end),
>> + TP_ARGS(start, end),
>> +
>> + TP_STRUCT__entry(
>> + __field( unsigned long, start )
>> + __field( unsigned long, end )
>> + ),
>> +
>> + TP_fast_assign(
>> + __entry->start = start;
>> + __entry->end = end;
>> + ),
>> +
>> + TP_printk("mmu notifier unmap range: %#08lx -- %#08lx",
>> + __entry->start, __entry->end)
>> +);
>> +
>> +TRACE_EVENT(kvm_set_spte_hva,
>> + TP_PROTO(unsigned long hva),
>> + TP_ARGS(hva),
>> +
>> + TP_STRUCT__entry(
>> + __field( unsigned long, hva )
>> + ),
>> +
>> + TP_fast_assign(
>> + __entry->hva = hva;
>> + ),
>> +
>> + TP_printk("mmu notifier set pte hva: %#08lx", __entry->hva) );
>>
>> #endif /* _TRACE_KVM_H */
>>
>>
>> _______________________________________________
>> kvmarm mailing list
>> kvmarm at lists.cs.columbia.edu
>> https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
^ permalink raw reply [flat|nested] 17+ messages in thread
* [PATCH v3 07/14] KVM: ARM: Inject IRQs and FIQs from userspace
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (5 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 06/14] KVM: ARM: Memory virtualization setup Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:49 ` [PATCH v3 08/14] KVM: ARM: World-switch implementation Christoffer Dall
` (6 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
From: Christoffer Dall <cdall@cs.columbia.edu>
All interrupt injection is now based on the VM ioctl KVM_IRQ_LINE. This
works semantically well for the GIC as we in fact raise/lower a line on
a machine component (the gic). The IOCTL uses the follwing struct.
struct kvm_irq_level {
union {
__u32 irq; /* GSI */
__s32 status; /* not used for KVM_IRQ_LEVEL */
};
__u32 level; /* 0 or 1 */
};
ARM can signal an interrupt either at the CPU level, or at the in-kernel irqchip
(GIC), and for in-kernel irqchip can tell the GIC to use PPIs designated for
specific cpus. The irq field is interpreted like this:
?bits: | 31 ... 24 | 23 ... 16 | 15 ... 0 |
field: | irq_type | vcpu_index | irq_number |
The irq_type field has the following values:
- irq_type[0]: out-of-kernel GIC: irq_number 0 is IRQ, irq_number 1 is FIQ
- irq_type[1]: in-kernel GIC: SPI, irq_number between 32 and 1019 (incl.)
(the vcpu_index field is ignored)
- irq_type[2]: in-kernel GIC: PPI, irq_number between 16 and 31 (incl.)
The irq_number thus corresponds to the irq ID in as in the GICv2 specs.
This is documented in Documentation/kvm/api.txt.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
Documentation/virtual/kvm/api.txt | 25 +++++++++++--
arch/arm/include/asm/kvm_arm.h | 1 +
arch/arm/include/uapi/asm/kvm.h | 21 +++++++++++
arch/arm/kvm/arm.c | 70 +++++++++++++++++++++++++++++++++++++
arch/arm/kvm/trace.h | 25 +++++++++++++
include/uapi/linux/kvm.h | 1 +
6 files changed, 139 insertions(+), 4 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index b56bbd5..4514292 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -615,15 +615,32 @@ created.
4.25 KVM_IRQ_LINE
Capability: KVM_CAP_IRQCHIP
-Architectures: x86, ia64
+Architectures: x86, ia64, arm
Type: vm ioctl
Parameters: struct kvm_irq_level
Returns: 0 on success, -1 on error
Sets the level of a GSI input to the interrupt controller model in the kernel.
-Requires that an interrupt controller model has been previously created with
-KVM_CREATE_IRQCHIP. Note that edge-triggered interrupts require the level
-to be set to 1 and then back to 0.
+On some architectures it is required that an interrupt controller model has
+been previously created with KVM_CREATE_IRQCHIP. Note that edge-triggered
+interrupts require the level to be set to 1 and then back to 0.
+
+ARM can signal an interrupt either at the CPU level, or at the in-kernel irqchip
+(GIC), and for in-kernel irqchip can tell the GIC to use PPIs designated for
+specific cpus. The irq field is interpreted like this:
+
+ ?bits: | 31 ... 24 | 23 ... 16 | 15 ... 0 |
+ field: | irq_type | vcpu_index | irq_id |
+
+The irq_type field has the following values:
+- irq_type[0]: out-of-kernel GIC: irq_id 0 is IRQ, irq_id 1 is FIQ
+- irq_type[1]: in-kernel GIC: SPI, irq_id between 32 and 1019 (incl.)
+ (the vcpu_index field is ignored)
+- irq_type[2]: in-kernel GIC: PPI, irq_id between 16 and 31 (incl.)
+
+(The irq_id field thus corresponds nicely to the IRQ ID in the ARM GIC specs)
+
+In both cases, level is used to raise/lower the line.
struct kvm_irq_level {
union {
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index f6e8f6f..4f54cda 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -68,6 +68,7 @@
#define HCR_GUEST_MASK (HCR_TSC | HCR_TSW | HCR_TWI | HCR_VM | HCR_BSU_IS | \
HCR_FB | HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | \
HCR_SWIO | HCR_TIDCP)
+#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
/* Hyp System Control Register (HSCTLR) bits */
#define HSCTLR_TE (1 << 30)
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index bfc2123..138a588c 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -22,6 +22,7 @@
#include <asm/types.h>
#define __KVM_HAVE_GUEST_DEBUG
+#define __KVM_HAVE_IRQ_LINE
#define KVM_REG_SIZE(id) \
(1U << (((id) & KVM_REG_SIZE_MASK) >> KVM_REG_SIZE_SHIFT))
@@ -80,4 +81,24 @@ struct kvm_arch_memory_slot {
#define KVM_REG_ARM_CORE (0x0010 << KVM_REG_ARM_COPROC_SHIFT)
#define KVM_REG_ARM_CORE_REG(name) (offsetof(struct kvm_regs, name) / 4)
+/* KVM_IRQ_LINE irq field index values */
+#define KVM_ARM_IRQ_TYPE_SHIFT 24
+#define KVM_ARM_IRQ_TYPE_MASK 0xff
+#define KVM_ARM_IRQ_VCPU_SHIFT 16
+#define KVM_ARM_IRQ_VCPU_MASK 0xff
+#define KVM_ARM_IRQ_NUM_SHIFT 0
+#define KVM_ARM_IRQ_NUM_MASK 0xffff
+
+/* irq_type field */
+#define KVM_ARM_IRQ_TYPE_CPU 0
+#define KVM_ARM_IRQ_TYPE_SPI 1
+#define KVM_ARM_IRQ_TYPE_PPI 2
+
+/* out-of-kernel GIC cpu interrupt injection irq_number field */
+#define KVM_ARM_IRQ_CPU_IRQ 0
+#define KVM_ARM_IRQ_CPU_FIQ 1
+
+/* Highest supported SPI, from VGIC_NR_IRQS */
+#define KVM_ARM_IRQ_GIC_MAX 127
+
#endif /* __ARM_KVM_H__ */
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 5ac3132..15e2ab1 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -24,6 +24,7 @@
#include <linux/fs.h>
#include <linux/mman.h>
#include <linux/sched.h>
+#include <linux/kvm.h>
#include <trace/events/kvm.h>
#define CREATE_TRACE_POINTS
@@ -272,6 +273,7 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
+ vcpu->cpu = cpu;
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -312,6 +314,74 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
return -EINVAL;
}
+static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
+{
+ int bit_index;
+ bool set;
+ unsigned long *ptr;
+
+ if (number == KVM_ARM_IRQ_CPU_IRQ)
+ bit_index = __ffs(HCR_VI);
+ else /* KVM_ARM_IRQ_CPU_FIQ */
+ bit_index = __ffs(HCR_VF);
+
+ ptr = (unsigned long *)&vcpu->arch.irq_lines;
+ if (level)
+ set = test_and_set_bit(bit_index, ptr);
+ else
+ set = test_and_clear_bit(bit_index, ptr);
+
+ /*
+ * If we didn't change anything, no need to wake up or kick other CPUs
+ */
+ if (set == level)
+ return 0;
+
+ /*
+ * The vcpu irq_lines field was updated, wake up sleeping VCPUs and
+ * trigger a world-switch round on the running physical CPU to set the
+ * virtual IRQ/FIQ fields in the HCR appropriately.
+ */
+ kvm_vcpu_kick(vcpu);
+
+ return 0;
+}
+
+int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level)
+{
+ u32 irq = irq_level->irq;
+ unsigned int irq_type, vcpu_idx, irq_num;
+ int nrcpus = atomic_read(&kvm->online_vcpus);
+ struct kvm_vcpu *vcpu = NULL;
+ bool level = irq_level->level;
+
+ irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK;
+ vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK;
+ irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK;
+
+ trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level);
+
+ if (irq_type == KVM_ARM_IRQ_TYPE_CPU ||
+ irq_type == KVM_ARM_IRQ_TYPE_PPI) {
+ if (vcpu_idx >= nrcpus)
+ return -EINVAL;
+
+ vcpu = kvm_get_vcpu(kvm, vcpu_idx);
+ if (!vcpu)
+ return -EINVAL;
+ }
+
+ switch (irq_type) {
+ case KVM_ARM_IRQ_TYPE_CPU:
+ if (irq_num > KVM_ARM_IRQ_CPU_FIQ)
+ return -EINVAL;
+
+ return vcpu_interrupt_line(vcpu, irq_num, level);
+ }
+
+ return -EINVAL;
+}
+
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index 862b2cc..105d1f7 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -39,6 +39,31 @@ TRACE_EVENT(kvm_exit,
TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
);
+TRACE_EVENT(kvm_irq_line,
+ TP_PROTO(unsigned int type, int vcpu_idx, int irq_num, int level),
+ TP_ARGS(type, vcpu_idx, irq_num, level),
+
+ TP_STRUCT__entry(
+ __field( unsigned int, type )
+ __field( int, vcpu_idx )
+ __field( int, irq_num )
+ __field( int, level )
+ ),
+
+ TP_fast_assign(
+ __entry->type = type;
+ __entry->vcpu_idx = vcpu_idx;
+ __entry->irq_num = irq_num;
+ __entry->level = level;
+ ),
+
+ TP_printk("Inject %s interrupt (%d), vcpu->idx: %d, num: %d, level: %d",
+ (__entry->type == KVM_ARM_IRQ_TYPE_CPU) ? "CPU" :
+ (__entry->type == KVM_ARM_IRQ_TYPE_PPI) ? "VGIC PPI" :
+ (__entry->type == KVM_ARM_IRQ_TYPE_SPI) ? "VGIC SPI" : "UNKNOWN",
+ __entry->type, __entry->vcpu_idx, __entry->irq_num, __entry->level)
+);
+
TRACE_EVENT(kvm_unmap_hva,
TP_PROTO(unsigned long hva),
TP_ARGS(hva),
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index ba9feed..72f018b 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -115,6 +115,7 @@ struct kvm_irq_level {
* ACPI gsi notion of irq.
* For IA-64 (APIC model) IOAPIC0: irq 0-23; IOAPIC1: irq 24-47..
* For X86 (standard AT mode) PIC0/1: irq 0-15. IOAPIC0: 0-23..
+ * For ARM: See Documentation/virtual/kvm/api.txt
*/
union {
__u32 irq;
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 08/14] KVM: ARM: World-switch implementation
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (6 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 07/14] KVM: ARM: Inject IRQs and FIQs from userspace Christoffer Dall
@ 2012-10-22 6:49 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 09/14] KVM: ARM: Emulation framework and CP15 emulation Christoffer Dall
` (5 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:49 UTC (permalink / raw)
To: linux-arm-kernel
Provides complete world-switch implementation to switch to other guests
running in non-secure modes. Includes Hyp exception handlers that
capture necessary exception information and stores the information on
the VCPU and KVM structures.
The following Hyp-ABI is also documented in the code:
Hyp-ABI: Calling HYP-mode functions from host (in SVC mode):
Switching to Hyp mode is done through a simple HVC #0 instruction. The
exception vector code will check that the HVC comes from VMID==0 and if
so will push the necessary state (SPSR, lr_usr) on the Hyp stack.
- r0 contains a pointer to a HYP function
- r1, r2, and r3 contain arguments to the above function.
- The HYP function will be called with its arguments in r0, r1 and r2.
On HYP function return, we return directly to SVC.
A call to a function executing in Hyp mode is performed like the following:
<svc code>
ldr r0, =BSYM(my_hyp_fn)
ldr r1, =my_param
hvc #0 ; Call my_hyp_fn(my_param) from HYP mode
<svc code>
Otherwise, the world-switch is pretty straight-forward. All state that
can be modified by the guest is first backed up on the Hyp stack and the
VCPU values is loaded onto the hardware. State, which is not loaded, but
theoretically modifiable by the guest is protected through the
virtualiation features to generate a trap and cause software emulation.
Upon guest returns, all state is restored from hardware onto the VCPU
struct and the original state is restored from the Hyp-stack onto the
hardware.
SMP support using the VMPIDR calculated on the basis of the host MPIDR
and overriding the low bits with KVM vcpu_id contributed by Marc Zyngier.
Reuse of VMIDs has been implemented by Antonios Motakis and adapated from
a separate patch into the appropriate patches introducing the
functionality. Note that the VMIDs are stored per VM as required by the ARM
architecture reference manual.
To support VFP/NEON we trap those instructions using the HPCTR. When
we trap, we switch the FPU. After a guest exit, the VFP state is
returned to the host. When disabling access to floating point
instructions, we also mask FPEXC_EN in order to avoid the guest
receiving Undefined instruction exceptions before we have a chance to
switch back the floating point state. We are reusing vfp_hard_struct,
so we depend on VFPv3 being enabled in the host kernel, if not, we still
trap cp10 and cp11 in order to inject an undefined instruction exception
whenever the guest tries to use VFP/NEON. VFP/NEON developed by
Antionios Motakis and Rusty Russell.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 38 ++++
arch/arm/include/asm/kvm_host.h | 9 +
arch/arm/kernel/asm-offsets.c | 23 ++
arch/arm/kvm/arm.c | 165 ++++++++++++++++
arch/arm/kvm/interrupts.S | 352 +++++++++++++++++++++++++++++++++-
arch/arm/kvm/interrupts_head.S | 409 +++++++++++++++++++++++++++++++++++++++
6 files changed, 993 insertions(+), 3 deletions(-)
create mode 100644 arch/arm/kvm/interrupts_head.S
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index 4f54cda..aecd05f 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -98,6 +98,18 @@
#define TTBCR_T0SZ 3
#define HTCR_MASK (TTBCR_T0SZ | TTBCR_IRGN0 | TTBCR_ORGN0 | TTBCR_SH0)
+/* Hyp System Trap Register */
+#define HSTR_T(x) (1 << x)
+#define HSTR_TTEE (1 << 16)
+#define HSTR_TJDBX (1 << 17)
+
+/* Hyp Coprocessor Trap Register */
+#define HCPTR_TCP(x) (1 << x)
+#define HCPTR_TCP_MASK (0x3fff)
+#define HCPTR_TASE (1 << 15)
+#define HCPTR_TTA (1 << 20)
+#define HCPTR_TCPAC (1 << 31)
+
/* Hyp Debug Configuration Register bits */
#define HDCR_TDRA (1 << 11)
#define HDCR_TDOSA (1 << 10)
@@ -128,5 +140,31 @@
#define VTTBR_X (5 - VTCR_GUEST_T0SZ)
#endif
+/* Hyp Syndrome Register (HSR) bits */
+#define HSR_EC_SHIFT (26)
+#define HSR_EC (0x3fU << HSR_EC_SHIFT)
+#define HSR_IL (1U << 25)
+#define HSR_ISS (HSR_IL - 1)
+#define HSR_ISV_SHIFT (24)
+#define HSR_ISV (1U << HSR_ISV_SHIFT)
+
+#define HSR_EC_UNKNOWN (0x00)
+#define HSR_EC_WFI (0x01)
+#define HSR_EC_CP15_32 (0x03)
+#define HSR_EC_CP15_64 (0x04)
+#define HSR_EC_CP14_MR (0x05)
+#define HSR_EC_CP14_LS (0x06)
+#define HSR_EC_CP_0_13 (0x07)
+#define HSR_EC_CP10_ID (0x08)
+#define HSR_EC_JAZELLE (0x09)
+#define HSR_EC_BXJ (0x0A)
+#define HSR_EC_CP14_64 (0x0C)
+#define HSR_EC_SVC_HYP (0x11)
+#define HSR_EC_HVC (0x12)
+#define HSR_EC_SMC (0x13)
+#define HSR_EC_IABT (0x20)
+#define HSR_EC_IABT_HYP (0x21)
+#define HSR_EC_DABT (0x24)
+#define HSR_EC_DABT_HYP (0x25)
#endif /* __ARM_KVM_ARM_H__ */
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 68d1005..5f5c975 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -21,6 +21,7 @@
#include <asm/kvm.h>
#include <asm/kvm_asm.h>
+#include <asm/fpstate.h>
#define KVM_MAX_VCPUS NR_CPUS
#define KVM_MEMORY_SLOTS 32
@@ -85,6 +86,14 @@ struct kvm_vcpu_arch {
u32 hxfar; /* Hyp Data/Inst Fault Address Register */
u32 hpfar; /* Hyp IPA Fault Address Register */
+ /* Floating point registers (VFP and Advanced SIMD/NEON) */
+ struct vfp_hard_struct vfp_guest;
+ struct vfp_hard_struct *vfp_host;
+
+ /*
+ * Anything that is not used directly from assembly code goes
+ * here.
+ */
/* IO related fields */
struct {
bool sign_extend; /* for byte/halfword loads */
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index c985b48..cf97d92 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -13,6 +13,7 @@
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
+#include <linux/kvm_host.h>
#include <asm/cacheflush.h>
#include <asm/glue-df.h>
#include <asm/glue-pf.h>
@@ -146,5 +147,27 @@ int main(void)
DEFINE(DMA_BIDIRECTIONAL, DMA_BIDIRECTIONAL);
DEFINE(DMA_TO_DEVICE, DMA_TO_DEVICE);
DEFINE(DMA_FROM_DEVICE, DMA_FROM_DEVICE);
+#ifdef CONFIG_KVM_ARM_HOST
+ DEFINE(VCPU_KVM, offsetof(struct kvm_vcpu, kvm));
+ DEFINE(VCPU_MIDR, offsetof(struct kvm_vcpu, arch.midr));
+ DEFINE(VCPU_CP15, offsetof(struct kvm_vcpu, arch.cp15));
+ DEFINE(VCPU_VFP_GUEST, offsetof(struct kvm_vcpu, arch.vfp_guest));
+ DEFINE(VCPU_VFP_HOST, offsetof(struct kvm_vcpu, arch.vfp_host));
+ DEFINE(VCPU_REGS, offsetof(struct kvm_vcpu, arch.regs));
+ DEFINE(VCPU_USR_REGS, offsetof(struct kvm_vcpu, arch.regs.usr_regs));
+ DEFINE(VCPU_SVC_REGS, offsetof(struct kvm_vcpu, arch.regs.svc_regs));
+ DEFINE(VCPU_ABT_REGS, offsetof(struct kvm_vcpu, arch.regs.abt_regs));
+ DEFINE(VCPU_UND_REGS, offsetof(struct kvm_vcpu, arch.regs.und_regs));
+ DEFINE(VCPU_IRQ_REGS, offsetof(struct kvm_vcpu, arch.regs.irq_regs));
+ DEFINE(VCPU_FIQ_REGS, offsetof(struct kvm_vcpu, arch.regs.fiq_regs));
+ DEFINE(VCPU_PC, offsetof(struct kvm_vcpu, arch.regs.pc));
+ DEFINE(VCPU_CPSR, offsetof(struct kvm_vcpu, arch.regs.cpsr));
+ DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines));
+ DEFINE(VCPU_HSR, offsetof(struct kvm_vcpu, arch.hsr));
+ DEFINE(VCPU_HxFAR, offsetof(struct kvm_vcpu, arch.hxfar));
+ DEFINE(VCPU_HPFAR, offsetof(struct kvm_vcpu, arch.hpfar));
+ DEFINE(VCPU_HYP_PC, offsetof(struct kvm_vcpu, arch.hyp_pc));
+ DEFINE(KVM_VTTBR, offsetof(struct kvm, arch.vttbr));
+#endif
return 0;
}
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 15e2ab1..3335d2b 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -40,6 +40,7 @@
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
+#include <asm/kvm_emulate.h>
#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
@@ -49,6 +50,10 @@ static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
static struct vfp_hard_struct __percpu *kvm_host_vfp_state;
static unsigned long hyp_default_vectors;
+/* The VMID used in the VTTBR */
+static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
+static u8 kvm_next_vmid;
+static DEFINE_SPINLOCK(kvm_vmid_lock);
int kvm_arch_hardware_enable(void *garbage)
{
@@ -264,6 +269,8 @@ int __attribute_const__ kvm_target_cpu(void)
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
+ /* Force users to call KVM_ARM_VCPU_INIT */
+ vcpu->arch.target = -1;
return 0;
}
@@ -274,6 +281,7 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
vcpu->cpu = cpu;
+ vcpu->arch.vfp_host = this_cpu_ptr(kvm_host_vfp_state);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -306,12 +314,167 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
int kvm_arch_vcpu_in_guest_mode(struct kvm_vcpu *v)
{
+ return v->mode == IN_GUEST_MODE;
+}
+
+static void reset_vm_context(void *info)
+{
+ kvm_call_hyp(__kvm_flush_vm_context);
+}
+
+/**
+ * need_new_vmid_gen - check that the VMID is still valid
+ * @kvm: The VM's VMID to checkt
+ *
+ * return true if there is a new generation of VMIDs being used
+ *
+ * The hardware supports only 256 values with the value zero reserved for the
+ * host, so we check if an assigned value belongs to a previous generation,
+ * which which requires us to assign a new value. If we're the first to use a
+ * VMID for the new generation, we must flush necessary caches and TLBs on all
+ * CPUs.
+ */
+static bool need_new_vmid_gen(struct kvm *kvm)
+{
+ return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen));
+}
+
+/**
+ * update_vttbr - Update the VTTBR with a valid VMID before the guest runs
+ * @kvm The guest that we are about to run
+ *
+ * Called from kvm_arch_vcpu_ioctl_run before entering the guest to ensure the
+ * VM has a valid VMID, otherwise assigns a new one and flushes corresponding
+ * caches and TLBs.
+ */
+static void update_vttbr(struct kvm *kvm)
+{
+ phys_addr_t pgd_phys;
+
+ if (!need_new_vmid_gen(kvm))
+ return;
+
+ spin_lock(&kvm_vmid_lock);
+
+ /* First user of a new VMID generation? */
+ if (unlikely(kvm_next_vmid == 0)) {
+ atomic64_inc(&kvm_vmid_gen);
+ kvm_next_vmid = 1;
+
+ /*
+ * On SMP we know no other CPUs can use this CPU's or
+ * each other's VMID since the kvm_vmid_lock blocks
+ * them from reentry to the guest.
+ */
+ on_each_cpu(reset_vm_context, NULL, 1);
+ }
+
+ kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen);
+ kvm->arch.vmid = kvm_next_vmid;
+ kvm_next_vmid++;
+
+ /* update vttbr to be used with the new vmid */
+ pgd_phys = virt_to_phys(kvm->arch.pgd);
+ kvm->arch.vttbr = pgd_phys & ((1LLU << 40) - 1)
+ & ~((2 << VTTBR_X) - 1);
+ kvm->arch.vttbr |= (u64)(kvm->arch.vmid) << 48;
+
+ spin_unlock(&kvm_vmid_lock);
+}
+
+/*
+ * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
+ * proper exit to QEMU.
+ */
+static int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ int exception_index)
+{
+ run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return 0;
}
+/**
+ * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code
+ * @vcpu: The VCPU pointer
+ * @run: The kvm_run structure pointer used for userspace state exchange
+ *
+ * This function is called through the VCPU_RUN ioctl called from user space. It
+ * will execute VM code in a loop until the time slice for the process is used
+ * or some emulation is needed from user space in which case the function will
+ * return with return value 0 and with the kvm_run structure filled in with the
+ * required data for the requested emulation.
+ */
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
- return -EINVAL;
+ int ret;
+ sigset_t sigsaved;
+
+ /* Make sure they initialize the vcpu with KVM_ARM_VCPU_INIT */
+ if (unlikely(vcpu->arch.target < 0))
+ return -ENOEXEC;
+
+ if (vcpu->sigset_active)
+ sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
+
+ ret = 1;
+ run->exit_reason = KVM_EXIT_UNKNOWN;
+ while (ret > 0) {
+ /*
+ * Check conditions before entering the guest
+ */
+ cond_resched();
+
+ update_vttbr(vcpu->kvm);
+
+ local_irq_disable();
+
+ /*
+ * Re-check atomic conditions
+ */
+ if (signal_pending(current)) {
+ ret = -EINTR;
+ run->exit_reason = KVM_EXIT_INTR;
+ }
+
+ if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
+ local_irq_enable();
+ continue;
+ }
+
+ /**************************************************************
+ * Enter the guest
+ */
+ trace_kvm_entry(*vcpu_pc(vcpu));
+ kvm_guest_enter();
+ vcpu->mode = IN_GUEST_MODE;
+
+ ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
+
+ vcpu->mode = OUTSIDE_GUEST_MODE;
+ kvm_guest_exit();
+ trace_kvm_exit(*vcpu_pc(vcpu));
+ /*
+ * We may have taken a host interrupt in HYP mode (ie
+ * while executing the guest). This interrupt is still
+ * pending, as we haven't serviced it yet!
+ *
+ * We're now back in SVC mode, with interrupts
+ * disabled. Enabling the interrupts now will have
+ * the effect of taking the interrupt again, in SVC
+ * mode this time.
+ */
+ local_irq_enable();
+
+ /*
+ * Back from guest
+ *************************************************************/
+
+ ret = handle_exit(vcpu, run, ret);
+ }
+
+ if (vcpu->sigset_active)
+ sigprocmask(SIG_SETMASK, &sigsaved, NULL);
+ return ret;
}
static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level)
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index 1c83022..d79f1d4 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -20,9 +20,12 @@
#include <linux/const.h>
#include <asm/unified.h>
#include <asm/page.h>
+#include <asm/ptrace.h>
#include <asm/asm-offsets.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_arm.h>
+#include <asm/vfpmacros.h>
+#include "interrupts_head.S"
.text
.align PAGE_SHIFT
@@ -32,36 +35,381 @@ __kvm_hyp_code_start:
/********************************************************************
* Flush per-VMID TLBs
+ *
+ * void __kvm_tlb_flush_vmid(struct kvm *kvm);
+ *
+ * We rely on the hardware to broadcast the TLB invalidation to all CPUs
+ * inside the inner-shareable domain (which is the case for all v7
+ * implementations). If we come across a non-IS SMP implementation, we'll
+ * have to use an IPI based mechanism. Until then, we stick to the simple
+ * hardware assisted version.
*/
ENTRY(__kvm_tlb_flush_vmid)
+ push {r2, r3}
+
+ add r0, r0, #KVM_VTTBR
+ ldrd r2, r3, [r0]
+ mcrr p15, 6, r2, r3, c2 @ Write VTTBR
+ isb
+ mcr p15, 0, r0, c8, c3, 0 @ TLBIALLIS (rt ignored)
+ dsb
+ isb
+ mov r2, #0
+ mov r3, #0
+ mcrr p15, 6, r2, r3, c2 @ Back to VMID #0
+ isb @ Not necessary if followed by eret
+
+ pop {r2, r3}
bx lr
ENDPROC(__kvm_tlb_flush_vmid)
/********************************************************************
* Flush TLBs and instruction caches of current CPU for all VMIDs
+ *
+ * void __kvm_flush_vm_context(void);
*/
ENTRY(__kvm_flush_vm_context)
+ mov r0, #0 @ rn parameter for c15 flushes is SBZ
+ mcr p15, 4, r0, c8, c7, 4 @ Invalidate Non-secure Non-Hyp TLB
+ mcr p15, 0, r0, c7, c5, 0 @ Invalidate instruction caches
+ dsb
+ isb @ Not necessary if followed by eret
+
bx lr
ENDPROC(__kvm_flush_vm_context)
+
/********************************************************************
* Hypervisor world-switch code
+ *
+ *
+ * int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
*/
ENTRY(__kvm_vcpu_run)
- bx lr
+ @ Save the vcpu pointer
+ mcr p15, 4, r0, c13, c0, 2 @ HTPIDR
+
+ save_host_regs
+
+ @ Store hardware CP15 state and load guest state
+ read_cp15_state
+ write_cp15_state 1, r0
+
+ @ If the host kernel has not been configured with VFPv3 support,
+ @ then it is safer if we deny guests from using it as well.
+#ifdef CONFIG_VFPv3
+ @ Set FPEXC_EN so the guest doesn't trap floating point instructions
+ VFPFMRX r2, FPEXC @ VMRS
+ push {r2}
+ orr r2, r2, #FPEXC_EN
+ VFPFMXR FPEXC, r2 @ VMSR
+#endif
+
+ @ Configure Hyp-role
+ configure_hyp_role 1, r0
+
+ @ Trap coprocessor CRx accesses
+ set_hstr 1
+ set_hcptr 1, (HCPTR_TTA | HCPTR_TCP(10) | HCPTR_TCP(11))
+ set_hdcr 1
+
+ @ Write configured ID register into MIDR alias
+ ldr r1, [r0, #VCPU_MIDR]
+ mcr p15, 4, r1, c0, c0, 0
+
+ @ Write guest view of MPIDR into VMPIDR
+ ldr r1, [r0, #CP15_OFFSET(c0_MPIDR)]
+ mcr p15, 4, r1, c0, c0, 5
+
+ @ Set up guest memory translation
+ ldr r1, [r0, #VCPU_KVM]
+ add r1, r1, #KVM_VTTBR
+ ldrd r2, r3, [r1]
+ mcrr p15, 6, r2, r3, c2 @ Write VTTBR
+
+ @ At this point, r0 must contain the pointer to the VCPU
+ restore_guest_regs
+ clrex @ Clear exclusive monitor
+ eret
+
+__kvm_vcpu_return:
+ /*
+ * return convention:
+ * vcpu r0, r1, r2 saved on the stack
+ * r0: exception code
+ * r1: vcpu pointer
+ */
+ save_guest_regs
+
+ @ Set VMID == 0
+ mov r2, #0
+ mov r3, #0
+ mcrr p15, 6, r2, r3, c2 @ Write VTTBR
+
+ @ Don't trap coprocessor accesses for host kernel
+ set_hstr 0
+ set_hdcr 0
+ set_hcptr 0, (HCPTR_TTA | HCPTR_TCP(10) | HCPTR_TCP(11))
+
+#ifdef CONFIG_VFPv3
+ @ Save floating point registers we if let guest use them.
+ tst r2, #(HCPTR_TCP(10) | HCPTR_TCP(11))
+ bne after_vfp_restore
+
+ @ Switch VFP/NEON hardware state to the host's
+ add r7, r1, #VCPU_VFP_GUEST
+ store_vfp_state r7
+ add r7, r1, #VCPU_VFP_HOST
+ ldr r7, [r7]
+ restore_vfp_state r7
+
+after_vfp_restore:
+ @ Restore FPEXC_EN which we clobbered on entry
+ pop {r2}
+ VFPFMXR FPEXC, r2
+#endif
+
+ @ Reset Hyp-role
+ configure_hyp_role 0, r1
+
+ @ Let host read hardware MIDR
+ mrc p15, 0, r2, c0, c0, 0
+ mcr p15, 4, r2, c0, c0, 0
+
+ @ Back to hardware MPIDR
+ mrc p15, 0, r2, c0, c0, 5
+ mcr p15, 4, r2, c0, c0, 5
+
+ @ Store guest CP15 state and restore host state
+ read_cp15_state 1, r1
+ write_cp15_state
+
+ restore_host_regs
+ clrex @ Clear exclusive monitor
+ bx lr @ return to IOCTL
ENTRY(kvm_call_hyp)
+ hvc #0
bx lr
/********************************************************************
* Hypervisor exception vector and handlers
+ *
+ *
+ * The KVM/ARM Hypervisor ABI is defined as follows:
+ *
+ * Entry to Hyp mode from the host kernel will happen _only_ when an HVC
+ * instruction is issued since all traps are disabled when running the host
+ * kernel as per the Hyp-mode initialization at boot time.
+ *
+ * HVC instructions cause a trap to the vector page + offset 0x18 (see hyp_hvc
+ * below) when the HVC instruction is called from SVC mode (i.e. a guest or the
+ * host kernel) and they cause a trap to the vector page + offset 0xc when HVC
+ * instructions are called from within Hyp-mode.
+ *
+ * Hyp-ABI: Calling HYP-mode functions from host (in SVC mode):
+ * Switching to Hyp mode is done through a simple HVC #0 instruction. The
+ * exception vector code will check that the HVC comes from VMID==0 and if
+ * so will push the necessary state (SPSR, lr_usr) on the Hyp stack.
+ * - r0 contains a pointer to a HYP function
+ * - r1, r2, and r3 contain arguments to the above function.
+ * - The HYP function will be called with its arguments in r0, r1 and r2.
+ * On HYP function return, we return directly to SVC.
+ *
+ * Note that the above is used to execute code in Hyp-mode from a host-kernel
+ * point of view, and is a different concept from performing a world-switch and
+ * executing guest code SVC mode (with a VMID != 0).
*/
+/* Handle undef, svc, pabt, or dabt by crashing with a user notice */
+.macro bad_exception exception_code, panic_str
+ push {r0-r2}
+ mrrc p15, 6, r0, r1, c2 @ Read VTTBR
+ lsr r1, r1, #16
+ ands r1, r1, #0xff
+ beq 99f
+
+ load_vcpu r1 @ Load VCPU pointer
+ .if \exception_code == ARM_EXCEPTION_DATA_ABORT
+ mrc p15, 4, r2, c5, c2, 0 @ HSR
+ mrc p15, 4, r0, c6, c0, 0 @ HDFAR
+ str r2, [r1, #VCPU_HSR]
+ str r0, [r1, #VCPU_HxFAR]
+ .endif
+ .if \exception_code == ARM_EXCEPTION_PREF_ABORT
+ mrc p15, 4, r2, c5, c2, 0 @ HSR
+ mrc p15, 4, r0, c6, c0, 2 @ HIFAR
+ str r2, [r1, #VCPU_HSR]
+ str r0, [r1, #VCPU_HxFAR]
+ .endif
+ mov r0, #\exception_code
+ b __kvm_vcpu_return
+
+ @ We were in the host already. Let's craft a panic-ing return to SVC.
+99: mrs r2, cpsr
+ bic r2, r2, #MODE_MASK
+ orr r2, r2, #SVC_MODE
+THUMB( orr r2, r2, #PSR_T_BIT )
+ msr spsr_cxsf, r2
+ mrs r1, ELR_hyp
+ ldr r2, =BSYM(panic)
+ msr ELR_hyp, r2
+ ldr r0, \panic_str
+ eret
+.endm
+
+ .text
+
.align 5
__kvm_hyp_vector:
.globl __kvm_hyp_vector
- nop
+
+ @ Hyp-mode exception vector
+ W(b) hyp_reset
+ W(b) hyp_undef
+ W(b) hyp_svc
+ W(b) hyp_pabt
+ W(b) hyp_dabt
+ W(b) hyp_hvc
+ W(b) hyp_irq
+ W(b) hyp_fiq
+
+ .align
+hyp_reset:
+ b hyp_reset
+
+ .align
+hyp_undef:
+ bad_exception ARM_EXCEPTION_UNDEFINED, und_die_str
+
+ .align
+hyp_svc:
+ bad_exception ARM_EXCEPTION_HVC, svc_die_str
+
+ .align
+hyp_pabt:
+ bad_exception ARM_EXCEPTION_PREF_ABORT, pabt_die_str
+
+ .align
+hyp_dabt:
+ bad_exception ARM_EXCEPTION_DATA_ABORT, dabt_die_str
+
+ .align
+hyp_hvc:
+ /*
+ * Getting here is either becuase of a trap from a guest or from calling
+ * HVC from the host kernel, which means "switch to Hyp mode".
+ */
+ push {r0, r1, r2}
+
+ @ Check syndrome register
+ mrc p15, 4, r0, c5, c2, 0 @ HSR
+ lsr r1, r0, #HSR_EC_SHIFT
+#ifdef CONFIG_VFPv3
+ cmp r1, #HSR_EC_CP_0_13
+ beq switch_to_guest_vfp
+#endif
+ cmp r1, #HSR_EC_HVC
+ bne guest_trap @ Not HVC instr.
+
+ /*
+ * Let's check if the HVC came from VMID 0 and allow simple
+ * switch to Hyp mode
+ */
+ mrrc p15, 6, r1, r2, c2
+ lsr r2, r2, #16
+ and r2, r2, #0xff
+ cmp r2, #0
+ bne guest_trap @ Guest called HVC
+
+host_switch_to_hyp:
+ pop {r0, r1, r2}
+
+ push {lr}
+ mrs lr, SPSR
+ push {lr}
+
+ mov lr, r0
+ mov r0, r1
+ mov r1, r2
+ mov r2, r3
+
+THUMB( orr lr, #1)
+ blx lr @ Call the HYP function
+
+ pop {lr}
+ msr SPSR_csxf, lr
+ pop {lr}
+ eret
+
+guest_trap:
+ load_vcpu r1 @ Load VCPU pointer
+ str r0, [r1, #VCPU_HSR]
+
+ @ Check if we need the fault information
+ lsr r0, r0, #HSR_EC_SHIFT
+ cmp r0, #HSR_EC_IABT
+ mrceq p15, 4, r2, c6, c0, 2 @ HIFAR
+ beq 2f
+ cmp r0, #HSR_EC_DABT
+ bne 1f
+ mrc p15, 4, r2, c6, c0, 0 @ HDFAR
+
+2: str r2, [r1, #VCPU_HxFAR]
+ mrc p15, 4, r2, c6, c0, 4 @ HPFAR
+ str r2, [r1, #VCPU_HPFAR]
+
+1: mov r0, #ARM_EXCEPTION_HVC
+ b __kvm_vcpu_return
+
+/*
+ * If VFPv3 support is not available, then we will not switch the VFP
+ * registers; however cp10 and cp11 accesses will still trap and fallback
+ * to the regular coprocessor emulation code, which currently will
+ * inject an undefined exception to the guest.
+ */
+#ifdef CONFIG_VFPv3
+switch_to_guest_vfp:
+ load_vcpu r0 @ Load VCPU pointer
+ push {r3-r7}
+
+ @ NEON/VFP used. Turn on VFP access.
+ set_hcptr 0, (HCPTR_TCP(10) | HCPTR_TCP(11))
+
+ @ Switch VFP/NEON hardware state to the guest's
+ add r7, r0, #VCPU_VFP_HOST
+ ldr r7, [r7]
+ store_vfp_state r7
+ add r7, r0, #VCPU_VFP_GUEST
+ restore_vfp_state r7
+
+ pop {r3-r7}
+ pop {r0-r2}
+ eret
+#endif
+
+ .align
+hyp_irq:
+ push {r0, r1, r2}
+ mov r0, #ARM_EXCEPTION_IRQ
+ load_vcpu r1 @ Load VCPU pointer
+ b __kvm_vcpu_return
+
+ .align
+hyp_fiq:
+ b hyp_fiq
+
+ .ltorg
+
+und_die_str:
+ .ascii "unexpected undefined exception in Hyp mode at: %#08x"
+pabt_die_str:
+ .ascii "unexpected prefetch abort in Hyp mode at: %#08x"
+dabt_die_str:
+ .ascii "unexpected data abort in Hyp mode at: %#08x"
+svc_die_str:
+ .ascii "unexpected HVC/SVC trap in Hyp mode at: %#08x"
/*
* The below lines makes sure the HYP mode code fits in a single page (the
diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S
new file mode 100644
index 0000000..2ac8b4a
--- /dev/null
+++ b/arch/arm/kvm/interrupts_head.S
@@ -0,0 +1,409 @@
+#define VCPU_USR_REG(_reg_nr) (VCPU_USR_REGS + (_reg_nr * 4))
+#define VCPU_USR_SP (VCPU_USR_REG(13))
+#define VCPU_USR_LR (VCPU_USR_REG(14))
+#define CP15_OFFSET(_cp15_reg_idx) (VCPU_CP15 + (_cp15_reg_idx * 4))
+
+/* Clobbers {r2-r6} */
+.macro store_vfp_state vfp_base
+ @ The VFPFMRX and VFPFMXR macros are the VMRS and VMSR instructions
+ VFPFMRX r2, FPEXC
+ @ Make sure VFP is enabled so we can touch the registers.
+ orr r6, r2, #FPEXC_EN
+ VFPFMXR FPEXC, r6
+
+ VFPFMRX r3, FPSCR
+ tst r2, #FPEXC_EX @ Check for VFP Subarchitecture
+ beq 1f
+ @ If FPEXC_EX is 0, then FPINST/FPINST2 reads are upredictable, so
+ @ we only need to save them if FPEXC_EX is set.
+ VFPFMRX r4, FPINST
+ tst r2, #FPEXC_FP2V
+ VFPFMRX r5, FPINST2, ne @ vmrsne
+ bic r6, r2, #FPEXC_EX @ FPEXC_EX disable
+ VFPFMXR FPEXC, r6
+1:
+ VFPFSTMIA \vfp_base, r6 @ Save VFP registers
+ stm \vfp_base, {r2-r5} @ Save FPEXC, FPSCR, FPINST, FPINST2
+.endm
+
+/* Assume FPEXC_EN is on and FPEXC_EX is off, clobbers {r2-r6} */
+.macro restore_vfp_state vfp_base
+ VFPFLDMIA \vfp_base, r6 @ Load VFP registers
+ ldm \vfp_base, {r2-r5} @ Load FPEXC, FPSCR, FPINST, FPINST2
+
+ VFPFMXR FPSCR, r3
+ tst r2, #FPEXC_EX @ Check for VFP Subarchitecture
+ beq 1f
+ VFPFMXR FPINST, r4
+ tst r2, #FPEXC_FP2V
+ VFPFMXR FPINST2, r5, ne
+1:
+ VFPFMXR FPEXC, r2 @ FPEXC (last, in case !EN)
+.endm
+
+/* These are simply for the macros to work - value don't have meaning */
+.equ usr, 0
+.equ svc, 1
+.equ abt, 2
+.equ und, 3
+.equ irq, 4
+.equ fiq, 5
+
+.macro push_host_regs_mode mode
+ mrs r2, SP_\mode
+ mrs r3, LR_\mode
+ mrs r4, SPSR_\mode
+ push {r2, r3, r4}
+.endm
+
+.macro save_host_regs
+ /* Hyp regs. Only ELR_hyp (SPSR_hyp already saved) */
+ mrs r2, ELR_hyp
+ push {r2}
+
+ /* usr regs */
+ push {r4-r12} @ r0-r3 are always clobbered
+ mrs r2, SP_usr
+ mov r3, lr
+ push {r2, r3}
+
+ push_host_regs_mode svc
+ push_host_regs_mode abt
+ push_host_regs_mode und
+ push_host_regs_mode irq
+
+ /* fiq regs */
+ mrs r2, r8_fiq
+ mrs r3, r9_fiq
+ mrs r4, r10_fiq
+ mrs r5, r11_fiq
+ mrs r6, r12_fiq
+ mrs r7, SP_fiq
+ mrs r8, LR_fiq
+ mrs r9, SPSR_fiq
+ push {r2-r9}
+.endm
+
+.macro pop_host_regs_mode mode
+ pop {r2, r3, r4}
+ msr SP_\mode, r2
+ msr LR_\mode, r3
+ msr SPSR_\mode, r4
+.endm
+
+.macro restore_host_regs
+ pop {r2-r9}
+ msr r8_fiq, r2
+ msr r9_fiq, r3
+ msr r10_fiq, r4
+ msr r11_fiq, r5
+ msr r12_fiq, r6
+ msr SP_fiq, r7
+ msr LR_fiq, r8
+ msr SPSR_fiq, r9
+
+ pop_host_regs_mode irq
+ pop_host_regs_mode und
+ pop_host_regs_mode abt
+ pop_host_regs_mode svc
+
+ pop {r2, r3}
+ msr SP_usr, r2
+ mov lr, r3
+ pop {r4-r12}
+
+ pop {r2}
+ msr ELR_hyp, r2
+.endm
+
+/*
+ * Restore SP, LR and SPSR for a given mode. offset is the offset of
+ * this mode's registers from the VCPU base.
+ * r0: VCPU address
+ * Clobbers r1, r2, r3, r4.
+ */
+.macro restore_guest_regs_mode mode, offset
+ add r1, r0, \offset
+ ldm r1, {r2, r3, r4}
+ msr SP_\mode, r2
+ msr LR_\mode, r3
+ msr SPSR_\mode, r4
+.endm
+
+/*
+ * Restore all guest registers.
+ * r0: VCPU address
+ * Clobbers *all* registers.
+ */
+.macro restore_guest_regs
+ restore_guest_regs_mode svc, #VCPU_SVC_REGS
+ restore_guest_regs_mode abt, #VCPU_ABT_REGS
+ restore_guest_regs_mode und, #VCPU_UND_REGS
+ restore_guest_regs_mode irq, #VCPU_IRQ_REGS
+
+ add r1, r0, #VCPU_FIQ_REGS
+ ldm r1, {r2-r9}
+ msr r8_fiq, r2
+ msr r9_fiq, r3
+ msr r10_fiq, r4
+ msr r11_fiq, r5
+ msr r12_fiq, r6
+ msr SP_fiq, r7
+ msr LR_fiq, r8
+ msr SPSR_fiq, r9
+
+ @ Load return state
+ ldr r2, [r0, #VCPU_PC]
+ ldr r3, [r0, #VCPU_CPSR]
+ msr ELR_hyp, r2
+ msr SPSR_cxsf, r3
+
+ @ Load user registers
+ ldr r2, [r0, #VCPU_USR_SP]
+ ldr r3, [r0, #VCPU_USR_LR]
+ msr SP_usr, r2
+ mov lr, r3
+ add r0, r0, #(VCPU_USR_REGS)
+ ldm r0, {r0-r12}
+.endm
+
+/*
+ * Save SP, LR and SPSR for a given mode. offset is the offset of
+ * this mode's registers from the VCPU base.
+ * r1: VCPU address
+ * Clobbers r2, r3, r4, r5.
+ */
+.macro save_guest_regs_mode mode, offset
+ add r2, r1, \offset
+ mrs r3, SP_\mode
+ mrs r4, LR_\mode
+ mrs r5, SPSR_\mode
+ stm r2, {r3, r4, r5}
+.endm
+
+/*
+ * Save all guest registers
+ * r1: VCPU address
+ * Expects guest's r0, r1, r2 on the stack.
+ * Clobbers r2, r3, r4, r5.
+ */
+.macro save_guest_regs
+ @ Store usr registers
+ add r2, r1, #VCPU_USR_REG(3)
+ stm r2, {r3-r12}
+ add r2, r1, #VCPU_USR_REG(0)
+ pop {r3, r4, r5} @ r0, r1, r2
+ stm r2, {r3, r4, r5}
+ mrs r2, SP_usr
+ mov r3, lr
+ str r2, [r1, #VCPU_USR_SP]
+ str r3, [r1, #VCPU_USR_LR]
+
+ @ Store return state
+ mrs r2, ELR_hyp
+ mrs r3, spsr
+ str r2, [r1, #VCPU_PC]
+ str r3, [r1, #VCPU_CPSR]
+
+ @ Store other guest registers
+ save_guest_regs_mode svc, #VCPU_SVC_REGS
+ save_guest_regs_mode abt, #VCPU_ABT_REGS
+ save_guest_regs_mode und, #VCPU_UND_REGS
+ save_guest_regs_mode irq, #VCPU_IRQ_REGS
+.endm
+
+/* Reads cp15 registers from hardware and stores them in memory
+ * @vcpu: If 0, registers are written in-order to the stack,
+ * otherwise to the VCPU struct pointed to by vcpup
+ * @vcpup: Register pointing to VCPU struct
+ */
+.macro read_cp15_state vcpu=0, vcpup
+ mrc p15, 0, r2, c1, c0, 0 @ SCTLR
+ mrc p15, 0, r3, c1, c0, 2 @ CPACR
+ mrc p15, 0, r4, c2, c0, 2 @ TTBCR
+ mrc p15, 0, r5, c3, c0, 0 @ DACR
+ mrrc p15, 0, r6, r7, c2 @ TTBR 0
+ mrrc p15, 1, r8, r9, c2 @ TTBR 1
+ mrc p15, 0, r10, c10, c2, 0 @ PRRR
+ mrc p15, 0, r11, c10, c2, 1 @ NMRR
+ mrc p15, 2, r12, c0, c0, 0 @ CSSELR
+
+ .if \vcpu == 0
+ push {r2-r12} @ Push CP15 registers
+ .else
+ str r2, [\vcpup, #CP15_OFFSET(c1_SCTLR)]
+ str r3, [\vcpup, #CP15_OFFSET(c1_CPACR)]
+ str r4, [\vcpup, #CP15_OFFSET(c2_TTBCR)]
+ str r5, [\vcpup, #CP15_OFFSET(c3_DACR)]
+ add \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR0)
+ strd r6, r7, [\vcpup]
+ add \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR1) - CP15_OFFSET(c2_TTBR0)
+ strd r8, r9, [\vcpup]
+ sub \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR1)
+ str r10, [\vcpup, #CP15_OFFSET(c10_PRRR)]
+ str r11, [\vcpup, #CP15_OFFSET(c10_NMRR)]
+ str r12, [\vcpup, #CP15_OFFSET(c0_CSSELR)]
+ .endif
+
+ mrc p15, 0, r2, c13, c0, 1 @ CID
+ mrc p15, 0, r3, c13, c0, 2 @ TID_URW
+ mrc p15, 0, r4, c13, c0, 3 @ TID_URO
+ mrc p15, 0, r5, c13, c0, 4 @ TID_PRIV
+ mrc p15, 0, r6, c5, c0, 0 @ DFSR
+ mrc p15, 0, r7, c5, c0, 1 @ IFSR
+ mrc p15, 0, r8, c5, c1, 0 @ ADFSR
+ mrc p15, 0, r9, c5, c1, 1 @ AIFSR
+ mrc p15, 0, r10, c6, c0, 0 @ DFAR
+ mrc p15, 0, r11, c6, c0, 2 @ IFAR
+ mrc p15, 0, r12, c12, c0, 0 @ VBAR
+
+ .if \vcpu == 0
+ push {r2-r12} @ Push CP15 registers
+ .else
+ str r2, [\vcpup, #CP15_OFFSET(c13_CID)]
+ str r3, [\vcpup, #CP15_OFFSET(c13_TID_URW)]
+ str r4, [\vcpup, #CP15_OFFSET(c13_TID_URO)]
+ str r5, [\vcpup, #CP15_OFFSET(c13_TID_PRIV)]
+ str r6, [\vcpup, #CP15_OFFSET(c5_DFSR)]
+ str r7, [\vcpup, #CP15_OFFSET(c5_IFSR)]
+ str r8, [\vcpup, #CP15_OFFSET(c5_ADFSR)]
+ str r9, [\vcpup, #CP15_OFFSET(c5_AIFSR)]
+ str r10, [\vcpup, #CP15_OFFSET(c6_DFAR)]
+ str r11, [\vcpup, #CP15_OFFSET(c6_IFAR)]
+ str r12, [\vcpup, #CP15_OFFSET(c12_VBAR)]
+ .endif
+.endm
+
+/* Reads cp15 registers from memory and writes them to hardware
+ * @vcpu: If 0, registers are read in-order from the stack,
+ * otherwise from the VCPU struct pointed to by vcpup
+ * @vcpup: Register pointing to VCPU struct
+ */
+.macro write_cp15_state vcpu=0, vcpup
+ .if \vcpu == 0
+ pop {r2-r12}
+ .else
+ ldr r2, [\vcpup, #CP15_OFFSET(c13_CID)]
+ ldr r3, [\vcpup, #CP15_OFFSET(c13_TID_URW)]
+ ldr r4, [\vcpup, #CP15_OFFSET(c13_TID_URO)]
+ ldr r5, [\vcpup, #CP15_OFFSET(c13_TID_PRIV)]
+ ldr r6, [\vcpup, #CP15_OFFSET(c5_DFSR)]
+ ldr r7, [\vcpup, #CP15_OFFSET(c5_IFSR)]
+ ldr r8, [\vcpup, #CP15_OFFSET(c5_ADFSR)]
+ ldr r9, [\vcpup, #CP15_OFFSET(c5_AIFSR)]
+ ldr r10, [\vcpup, #CP15_OFFSET(c6_DFAR)]
+ ldr r11, [\vcpup, #CP15_OFFSET(c6_IFAR)]
+ ldr r12, [\vcpup, #CP15_OFFSET(c12_VBAR)]
+ .endif
+
+ mcr p15, 0, r2, c13, c0, 1 @ CID
+ mcr p15, 0, r3, c13, c0, 2 @ TID_URW
+ mcr p15, 0, r4, c13, c0, 3 @ TID_URO
+ mcr p15, 0, r5, c13, c0, 4 @ TID_PRIV
+ mcr p15, 0, r6, c5, c0, 0 @ DFSR
+ mcr p15, 0, r7, c5, c0, 1 @ IFSR
+ mcr p15, 0, r8, c5, c1, 0 @ ADFSR
+ mcr p15, 0, r9, c5, c1, 1 @ AIFSR
+ mcr p15, 0, r10, c6, c0, 0 @ DFAR
+ mcr p15, 0, r11, c6, c0, 2 @ IFAR
+ mcr p15, 0, r12, c12, c0, 0 @ VBAR
+
+ .if \vcpu == 0
+ pop {r2-r12}
+ .else
+ ldr r2, [\vcpup, #CP15_OFFSET(c1_SCTLR)]
+ ldr r3, [\vcpup, #CP15_OFFSET(c1_CPACR)]
+ ldr r4, [\vcpup, #CP15_OFFSET(c2_TTBCR)]
+ ldr r5, [\vcpup, #CP15_OFFSET(c3_DACR)]
+ add \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR0)
+ ldrd r6, r7, [\vcpup]
+ add \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR1) - CP15_OFFSET(c2_TTBR0)
+ ldrd r8, r9, [\vcpup]
+ sub \vcpup, \vcpup, #CP15_OFFSET(c2_TTBR1)
+ ldr r10, [\vcpup, #CP15_OFFSET(c10_PRRR)]
+ ldr r11, [\vcpup, #CP15_OFFSET(c10_NMRR)]
+ ldr r12, [\vcpup, #CP15_OFFSET(c0_CSSELR)]
+ .endif
+
+ mcr p15, 0, r2, c1, c0, 0 @ SCTLR
+ mcr p15, 0, r3, c1, c0, 2 @ CPACR
+ mcr p15, 0, r4, c2, c0, 2 @ TTBCR
+ mcr p15, 0, r5, c3, c0, 0 @ DACR
+ mcrr p15, 0, r6, r7, c2 @ TTBR 0
+ mcrr p15, 1, r8, r9, c2 @ TTBR 1
+ mcr p15, 0, r10, c10, c2, 0 @ PRRR
+ mcr p15, 0, r11, c10, c2, 1 @ NMRR
+ mcr p15, 2, r12, c0, c0, 0 @ CSSELR
+.endm
+
+/*
+ * Save the VGIC CPU state into memory
+ * @vcpup: Register pointing to VCPU struct
+ */
+.macro save_vgic_state vcpup
+.endm
+
+/*
+ * Restore the VGIC CPU state from memory
+ * @vcpup: Register pointing to VCPU struct
+ */
+.macro restore_vgic_state vcpup
+.endm
+
+/* Configures the HSTR (Hyp System Trap Register) on entry/return
+ * (hardware reset value is 0) */
+.macro set_hstr entry
+ mrc p15, 4, r2, c1, c1, 3
+ ldr r3, =HSTR_T(15)
+ .if \entry == 1
+ orr r2, r2, r3 @ Trap CR{15}
+ .else
+ bic r2, r2, r3 @ Don't trap any CRx accesses
+ .endif
+ mcr p15, 4, r2, c1, c1, 3
+.endm
+
+/* Configures the HCPTR (Hyp Coprocessor Trap Register) on entry/return
+ * (hardware reset value is 0). Keep previous value in r2. */
+.macro set_hcptr entry, mask
+ mrc p15, 4, r2, c1, c1, 2
+ ldr r3, =\mask
+ .if \entry == 1
+ orr r3, r2, r3 @ Trap coproc-accesses defined in mask
+ .else
+ bic r3, r2, r3 @ Don't trap defined coproc-accesses
+ .endif
+ mcr p15, 4, r3, c1, c1, 2
+.endm
+
+/* Configures the HDCR (Hyp Debug Configuration Register) on entry/return
+ * (hardware reset value is 0) */
+.macro set_hdcr entry
+ mrc p15, 4, r2, c1, c1, 1
+ ldr r3, =(HDCR_TPM|HDCR_TPMCR)
+ .if \entry == 1
+ orr r2, r2, r3 @ Trap some perfmon accesses
+ .else
+ bic r2, r2, r3 @ Don't trap any perfmon accesses
+ .endif
+ mcr p15, 4, r2, c1, c1, 1
+.endm
+
+/* Enable/Disable: stage-2 trans., trap interrupts, trap wfi, trap smc */
+.macro configure_hyp_role entry, vcpu_ptr
+ mrc p15, 4, r2, c1, c1, 0 @ HCR
+ bic r2, r2, #HCR_VIRT_EXCP_MASK
+ ldr r3, =HCR_GUEST_MASK
+ .if \entry == 1
+ orr r2, r2, r3
+ ldr r3, [\vcpu_ptr, #VCPU_IRQ_LINES]
+ orr r2, r2, r3
+ .else
+ bic r2, r2, r3
+ .endif
+ mcr p15, 4, r2, c1, c1, 0
+.endm
+
+.macro load_vcpu reg
+ mrc p15, 4, \reg, c13, c0, 2 @ HTPIDR
+.endm
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 09/14] KVM: ARM: Emulation framework and CP15 emulation
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (7 preceding siblings ...)
2012-10-22 6:49 ` [PATCH v3 08/14] KVM: ARM: World-switch implementation Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 10/14] KVM: ARM: User space API for getting/setting co-proc registers Christoffer Dall
` (4 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
Adds a new important function in the main KVM/ARM code called
handle_exit() which is called from kvm_arch_vcpu_ioctl_run() on returns
from guest execution. This function examines the Hyp-Syndrome-Register
(HSR), which contains information telling KVM what caused the exit from
the guest.
Some of the reasons for an exit are CP15 accesses, which are
not allowed from the guest and this commit handles these exits by
emulating the intended operation in software and skipping the guest
instruction.
Minor notes about the coproc register reset:
1) We reserve a value of 0 as an invalid cp15 offset, to catch bugs in our
table, at cost of 4 bytes per vcpu.
2) Added comments on the table indicating how we handle each register, for
simplicity of understanding.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 9 +
arch/arm/include/asm/kvm_coproc.h | 14 +
arch/arm/include/asm/kvm_emulate.h | 6 +
arch/arm/include/asm/kvm_host.h | 4
arch/arm/kvm/Makefile | 3
arch/arm/kvm/arm.c | 175 +++++++++++++++++
arch/arm/kvm/coproc.c | 363 ++++++++++++++++++++++++++++++++++++
arch/arm/kvm/coproc.h | 153 +++++++++++++++
arch/arm/kvm/coproc_a15.c | 164 ++++++++++++++++
arch/arm/kvm/emulate.c | 218 ++++++++++++++++++++++
arch/arm/kvm/trace.h | 45 ++++
11 files changed, 1149 insertions(+), 5 deletions(-)
create mode 100644 arch/arm/kvm/coproc.h
create mode 100644 arch/arm/kvm/coproc_a15.c
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index aecd05f..6b8bb51 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -70,6 +70,11 @@
HCR_SWIO | HCR_TIDCP)
#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF)
+/* System Control Register (SCTLR) bits */
+#define SCTLR_TE (1 << 30)
+#define SCTLR_EE (1 << 25)
+#define SCTLR_V (1 << 13)
+
/* Hyp System Control Register (HSCTLR) bits */
#define HSCTLR_TE (1 << 30)
#define HSCTLR_EE (1 << 25)
@@ -147,6 +152,10 @@
#define HSR_ISS (HSR_IL - 1)
#define HSR_ISV_SHIFT (24)
#define HSR_ISV (1U << HSR_ISV_SHIFT)
+#define HSR_CV_SHIFT (24)
+#define HSR_CV (1U << HSR_CV_SHIFT)
+#define HSR_COND_SHIFT (20)
+#define HSR_COND (0xfU << HSR_COND_SHIFT)
#define HSR_EC_UNKNOWN (0x00)
#define HSR_EC_WFI (0x01)
diff --git a/arch/arm/include/asm/kvm_coproc.h b/arch/arm/include/asm/kvm_coproc.h
index b6d023d..bd1ace0 100644
--- a/arch/arm/include/asm/kvm_coproc.h
+++ b/arch/arm/include/asm/kvm_coproc.h
@@ -21,4 +21,18 @@
void kvm_reset_coprocs(struct kvm_vcpu *vcpu);
+struct kvm_coproc_target_table {
+ unsigned target;
+ const struct coproc_reg *table;
+ size_t num;
+};
+void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table);
+
+int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run);
+void kvm_coproc_table_init(void);
#endif /* __ARM_KVM_COPROC_H__ */
diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index 7d3e904..ac48156 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -25,6 +25,12 @@
u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num);
u32 *vcpu_spsr(struct kvm_vcpu *vcpu);
+int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run);
+void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr);
+void kvm_inject_undefined(struct kvm_vcpu *vcpu);
+void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
+void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr);
+
static inline u32 *vcpu_pc(struct kvm_vcpu *vcpu)
{
return &vcpu->arch.regs.pc;
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 5f5c975..2ce654c 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -94,6 +94,10 @@ struct kvm_vcpu_arch {
* Anything that is not used directly from assembly code goes
* here.
*/
+ /* dcache set/way operation pending */
+ int last_pcpu;
+ cpumask_t require_dcache_flush;
+
/* IO related fields */
struct {
bool sign_extend; /* for byte/halfword loads */
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index 7acf3ea..ea5b282 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -18,4 +18,5 @@ obj-$(CONFIG_KVM_ARM_HOST) += init.o interrupts.o
obj-$(CONFIG_KVM_ARM_HOST) += $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o)
-obj-$(CONFIG_KVM_ARM_HOST) += arm.o guest.o mmu.o emulate.o reset.o coproc.o
+obj-$(CONFIG_KVM_ARM_HOST) += arm.o guest.o mmu.o emulate.o reset.o
+obj-$(CONFIG_KVM_ARM_HOST) += coproc.o coproc_a15.o
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 3335d2b..c547797 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -36,11 +36,14 @@
#include <asm/mman.h>
#include <asm/cputype.h>
#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
#include <asm/virt.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_emulate.h>
+#include <asm/kvm_coproc.h>
+#include <asm/opcodes.h>
#ifdef REQUIRES_VIRT
__asm__(".arch_extension virt");
@@ -282,6 +285,17 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
vcpu->cpu = cpu;
vcpu->arch.vfp_host = this_cpu_ptr(kvm_host_vfp_state);
+
+ /*
+ * Check whether this vcpu requires the cache to be flushed on
+ * this physical CPU. This is a consequence of doing dcache
+ * operations by set/way on this vcpu. We do it here to be in
+ * a non-preemptible section.
+ */
+ if (cpumask_test_cpu(cpu, &vcpu->arch.require_dcache_flush)) {
+ cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);
+ flush_cache_all(); /* We'd really want v7_flush_dcache_all() */
+ }
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
@@ -307,9 +321,16 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
return -EINVAL;
}
+/**
+ * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled
+ * @v: The VCPU pointer
+ *
+ * If the guest CPU is not waiting for interrupts or an interrupt line is
+ * asserted, the CPU is by definition runnable.
+ */
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
- return 0;
+ return !!v->arch.irq_lines;
}
int kvm_arch_vcpu_in_guest_mode(struct kvm_vcpu *v)
@@ -382,6 +403,114 @@ static void update_vttbr(struct kvm *kvm)
spin_unlock(&kvm_vmid_lock);
}
+static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /* SVC called from Hyp mode should never get here */
+ kvm_debug("SVC called from Hyp mode shouldn't go here\n");
+ BUG();
+ return -EINVAL; /* Squash warning */
+}
+
+static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /*
+ * Guest called HVC instruction:
+ * Let it know we don't want that by injecting an undefined exception.
+ */
+ kvm_debug("hvc: %x (at %08x)", vcpu->arch.hsr & ((1 << 16) - 1),
+ *vcpu_pc(vcpu));
+ kvm_debug(" HSR: %8x", vcpu->arch.hsr);
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /* We don't support SMC; don't do that. */
+ kvm_debug("smc: at %08x", *vcpu_pc(vcpu));
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+static int handle_pabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /* The hypervisor should never cause aborts */
+ kvm_err("Prefetch Abort taken from Hyp mode at %#08x (HSR: %#08x)\n",
+ vcpu->arch.hxfar, vcpu->arch.hsr);
+ return -EFAULT;
+}
+
+static int handle_dabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /* This is either an error in the ws. code or an external abort */
+ kvm_err("Data Abort taken from Hyp mode at %#08x (HSR: %#08x)\n",
+ vcpu->arch.hxfar, vcpu->arch.hsr);
+ return -EFAULT;
+}
+
+typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *);
+static exit_handle_fn arm_exit_handlers[] = {
+ [HSR_EC_WFI] = kvm_handle_wfi,
+ [HSR_EC_CP15_32] = kvm_handle_cp15_32,
+ [HSR_EC_CP15_64] = kvm_handle_cp15_64,
+ [HSR_EC_CP14_MR] = kvm_handle_cp14_access,
+ [HSR_EC_CP14_LS] = kvm_handle_cp14_load_store,
+ [HSR_EC_CP14_64] = kvm_handle_cp14_access,
+ [HSR_EC_CP_0_13] = kvm_handle_cp_0_13_access,
+ [HSR_EC_CP10_ID] = kvm_handle_cp10_id,
+ [HSR_EC_SVC_HYP] = handle_svc_hyp,
+ [HSR_EC_HVC] = handle_hvc,
+ [HSR_EC_SMC] = handle_smc,
+ [HSR_EC_IABT] = kvm_handle_guest_abort,
+ [HSR_EC_IABT_HYP] = handle_pabt_hyp,
+ [HSR_EC_DABT] = kvm_handle_guest_abort,
+ [HSR_EC_DABT_HYP] = handle_dabt_hyp,
+};
+
+/*
+ * A conditional instruction is allowed to trap, even though it
+ * wouldn't be executed. So let's re-implement the hardware, in
+ * software!
+ */
+static bool kvm_condition_valid(struct kvm_vcpu *vcpu)
+{
+ unsigned long cpsr, cond, insn;
+
+ /*
+ * Exception Code 0 can only happen if we set HCR.TGE to 1, to
+ * catch undefined instructions, and then we won't get past
+ * the arm_exit_handlers test anyway.
+ */
+ BUG_ON(((vcpu->arch.hsr & HSR_EC) >> HSR_EC_SHIFT) == 0);
+
+ /* Top two bits non-zero? Unconditional. */
+ if (vcpu->arch.hsr >> 30)
+ return true;
+
+ cpsr = *vcpu_cpsr(vcpu);
+
+ /* Is condition field valid? */
+ if ((vcpu->arch.hsr & HSR_CV) >> HSR_CV_SHIFT)
+ cond = (vcpu->arch.hsr & HSR_COND) >> HSR_COND_SHIFT;
+ else {
+ /* This can happen in Thumb mode: examine IT state. */
+ unsigned long it;
+
+ it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3);
+
+ /* it == 0 => unconditional. */
+ if (it == 0)
+ return true;
+
+ /* The cond for this insn works out as the top 4 bits. */
+ cond = (it >> 4);
+ }
+
+ /* Shift makes it look like an ARM-mode instruction */
+ insn = cond << 28;
+ return arm_check_condition(insn, cpsr) != ARM_OPCODE_CONDTEST_FAIL;
+}
+
/*
* Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on
* proper exit to QEMU.
@@ -389,8 +518,46 @@ static void update_vttbr(struct kvm *kvm)
static int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
int exception_index)
{
- run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
- return 0;
+ unsigned long hsr_ec;
+
+ switch (exception_index) {
+ case ARM_EXCEPTION_IRQ:
+ return 1;
+ case ARM_EXCEPTION_UNDEFINED:
+ kvm_err("Undefined exception in Hyp mode at: %#08x\n",
+ vcpu->arch.hyp_pc);
+ BUG();
+ panic("KVM: Hypervisor undefined exception!\n");
+ case ARM_EXCEPTION_DATA_ABORT:
+ case ARM_EXCEPTION_PREF_ABORT:
+ case ARM_EXCEPTION_HVC:
+ hsr_ec = (vcpu->arch.hsr & HSR_EC) >> HSR_EC_SHIFT;
+
+ if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers)
+ || !arm_exit_handlers[hsr_ec]) {
+ kvm_err("Unkown exception class: %#08lx, "
+ "hsr: %#08x\n", hsr_ec,
+ (unsigned int)vcpu->arch.hsr);
+ BUG();
+ }
+
+ /*
+ * See ARM ARM B1.14.1: "Hyp traps on instructions
+ * that fail their condition code check"
+ */
+ if (!kvm_condition_valid(vcpu)) {
+ bool is_wide = vcpu->arch.hsr & HSR_IL;
+ kvm_skip_instr(vcpu, is_wide);
+ return 1;
+ }
+
+ return arm_exit_handlers[hsr_ec](vcpu, run);
+ default:
+ kvm_pr_unimpl("Unsupported exception type: %d",
+ exception_index);
+ run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+ return 0;
+ }
}
/**
@@ -451,6 +618,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
vcpu->mode = OUTSIDE_GUEST_MODE;
+ vcpu->arch.last_pcpu = smp_processor_id();
kvm_guest_exit();
trace_kvm_exit(*vcpu_pc(vcpu));
/*
@@ -764,6 +932,7 @@ int kvm_arch_init(void *opaque)
if (err)
goto out_err;
+ kvm_coproc_table_init();
return 0;
out_err:
return err;
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 4b9dad8..722efe3 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -1,6 +1,7 @@
/*
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
- * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ * Authors: Rusty Russell <rusty@rustcorp.com.au>
+ * Christoffer Dall <c.dall@virtualopensystems.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
@@ -15,8 +16,368 @@
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+#include <linux/mm.h>
#include <linux/kvm_host.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_host.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_coproc.h>
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <trace/events/kvm.h>
+#include "trace.h"
+#include "coproc.h"
+
+
+/******************************************************************************
+ * Co-processor emulation
+ *****************************************************************************/
+
+int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ /*
+ * We can get here, if the host has been built without VFPv3 support,
+ * but the guest attempted a floating point operation.
+ */
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+/* See note at ARM ARM B1.14.4 */
+static bool access_dcsw(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ u32 val;
+ int cpu;
+
+ cpu = get_cpu();
+
+ if (!p->is_write)
+ return read_from_write_only(vcpu, p);
+
+ cpumask_setall(&vcpu->arch.require_dcache_flush);
+ cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);
+
+ /* If we were already preempted, take the long way around */
+ if (cpu != vcpu->arch.last_pcpu) {
+ flush_cache_all();
+ goto done;
+ }
+
+ val = *vcpu_reg(vcpu, p->Rt1);
+
+ switch (p->CRm) {
+ case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */
+ case 14: /* DCCISW */
+ asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val));
+ break;
+
+ case 10: /* DCCSW */
+ asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val));
+ break;
+ }
+
+done:
+ put_cpu();
+
+ return true;
+}
+
+/*
+ * We could trap ID_DFR0 and tell the guest we don't support performance
+ * monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was
+ * NAKed, so it will read the PMCR anyway.
+ *
+ * Therefore we tell the guest we have 0 counters. Unfortunately, we
+ * must always support PMCCNTR (the cycle counter): we just RAZ/WI for
+ * all PM registers, which doesn't crash the guest kernel at least.
+ */
+static bool pm_fake(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ if (p->is_write)
+ return ignore_write(vcpu, p);
+ else
+ return read_zero(vcpu, p);
+}
+
+#define access_pmcr pm_fake
+#define access_pmcntenset pm_fake
+#define access_pmcntenclr pm_fake
+#define access_pmovsr pm_fake
+#define access_pmselr pm_fake
+#define access_pmceid0 pm_fake
+#define access_pmceid1 pm_fake
+#define access_pmccntr pm_fake
+#define access_pmxevtyper pm_fake
+#define access_pmxevcntr pm_fake
+#define access_pmuserenr pm_fake
+#define access_pmintenset pm_fake
+#define access_pmintenclr pm_fake
+
+/* Architected CP15 registers.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ */
+static const struct coproc_reg cp15_regs[] = {
+ /* CSSELR: swapped by interrupt.S. */
+ { CRn( 0), CRm( 0), Op1( 2), Op2( 0), is32,
+ NULL, reset_unknown, c0_CSSELR },
+
+ /* TTBR0/TTBR1: swapped by interrupt.S. */
+ { CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 },
+ { CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 },
+
+ /* TTBCR: swapped by interrupt.S. */
+ { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32,
+ NULL, reset_val, c2_TTBCR, 0x00000000 },
+
+ /* DACR: swapped by interrupt.S. */
+ { CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32,
+ NULL, reset_unknown, c3_DACR },
+
+ /* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */
+ { CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32,
+ NULL, reset_unknown, c5_DFSR },
+ { CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32,
+ NULL, reset_unknown, c5_IFSR },
+ { CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32,
+ NULL, reset_unknown, c5_ADFSR },
+ { CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32,
+ NULL, reset_unknown, c5_AIFSR },
+
+ /* DFAR/IFAR: swapped by interrupt.S. */
+ { CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32,
+ NULL, reset_unknown, c6_DFAR },
+ { CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32,
+ NULL, reset_unknown, c6_IFAR },
+ /*
+ * DC{C,I,CI}SW operations:
+ */
+ { CRn( 7), CRm( 6), Op1( 0), Op2( 2), is32, access_dcsw},
+ { CRn( 7), CRm(10), Op1( 0), Op2( 2), is32, access_dcsw},
+ { CRn( 7), CRm(14), Op1( 0), Op2( 2), is32, access_dcsw},
+ /*
+ * Dummy performance monitor implementation.
+ */
+ { CRn( 9), CRm(12), Op1( 0), Op2( 0), is32, access_pmcr},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 1), is32, access_pmcntenset},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 2), is32, access_pmcntenclr},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 3), is32, access_pmovsr},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 5), is32, access_pmselr},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 6), is32, access_pmceid0},
+ { CRn( 9), CRm(12), Op1( 0), Op2( 7), is32, access_pmceid1},
+ { CRn( 9), CRm(13), Op1( 0), Op2( 0), is32, access_pmccntr},
+ { CRn( 9), CRm(13), Op1( 0), Op2( 1), is32, access_pmxevtyper},
+ { CRn( 9), CRm(13), Op1( 0), Op2( 2), is32, access_pmxevcntr},
+ { CRn( 9), CRm(14), Op1( 0), Op2( 0), is32, access_pmuserenr},
+ { CRn( 9), CRm(14), Op1( 0), Op2( 1), is32, access_pmintenset},
+ { CRn( 9), CRm(14), Op1( 0), Op2( 2), is32, access_pmintenclr},
+
+ /* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */
+ { CRn(10), CRm( 2), Op1( 0), Op2( 0), is32,
+ NULL, reset_unknown, c10_PRRR},
+ { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32,
+ NULL, reset_unknown, c10_NMRR},
+
+ /* VBAR: swapped by interrupt.S. */
+ { CRn(12), CRm( 0), Op1( 0), Op2( 0), is32,
+ NULL, reset_val, c12_VBAR, 0x00000000 },
+
+ /* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */
+ { CRn(13), CRm( 0), Op1( 0), Op2( 1), is32,
+ NULL, reset_val, c13_CID, 0x00000000 },
+ { CRn(13), CRm( 0), Op1( 0), Op2( 2), is32,
+ NULL, reset_unknown, c13_TID_URW },
+ { CRn(13), CRm( 0), Op1( 0), Op2( 3), is32,
+ NULL, reset_unknown, c13_TID_URO },
+ { CRn(13), CRm( 0), Op1( 0), Op2( 4), is32,
+ NULL, reset_unknown, c13_TID_PRIV },
+};
+
+/* Target specific emulation tables */
+static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS];
+
+void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table)
+{
+ target_tables[table->target] = table;
+}
+
+/* Get specific register table for this target. */
+static const struct coproc_reg *get_target_table(unsigned target, size_t *num)
+{
+ struct kvm_coproc_target_table *table;
+
+ table = target_tables[target];
+ *num = table->num;
+ return table->table;
+}
+
+static const struct coproc_reg *find_reg(const struct coproc_params *params,
+ const struct coproc_reg table[],
+ unsigned int num)
+{
+ unsigned int i;
+
+ for (i = 0; i < num; i++) {
+ const struct coproc_reg *r = &table[i];
+
+ if (params->is_64bit != r->is_64)
+ continue;
+ if (params->CRn != r->CRn)
+ continue;
+ if (params->CRm != r->CRm)
+ continue;
+ if (params->Op1 != r->Op1)
+ continue;
+ if (params->Op2 != r->Op2)
+ continue;
+
+ return r;
+ }
+ return NULL;
+}
+
+static int emulate_cp15(struct kvm_vcpu *vcpu,
+ const struct coproc_params *params)
+{
+ size_t num;
+ const struct coproc_reg *table, *r;
+
+ trace_kvm_emulate_cp15_imp(params->Op1, params->Rt1, params->CRn,
+ params->CRm, params->Op2, params->is_write);
+
+ table = get_target_table(vcpu->arch.target, &num);
+
+ /* Search target-specific then generic table. */
+ r = find_reg(params, table, num);
+ if (!r)
+ r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs));
+
+ if (likely(r)) {
+ /* If we don't have an accessor, we should never get here! */
+ BUG_ON(!r->access);
+
+ if (likely(r->access(vcpu, params, r))) {
+ /* Skip instruction, since it was emulated */
+ kvm_skip_instr(vcpu, (vcpu->arch.hsr >> 25) & 1);
+ return 1;
+ }
+ /* If access function fails, it should complain. */
+ } else {
+ kvm_err("Unsupported guest CP15 access at: %08x\n",
+ *vcpu_pc(vcpu));
+ print_cp_instr(params);
+ }
+ kvm_inject_undefined(vcpu);
+ return 1;
+}
+
+/**
+ * kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access
+ * @vcpu: The VCPU pointer
+ * @run: The kvm_run struct
+ */
+int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ struct coproc_params params;
+
+ params.CRm = (vcpu->arch.hsr >> 1) & 0xf;
+ params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf;
+ params.is_write = ((vcpu->arch.hsr & 1) == 0);
+ params.is_64bit = true;
+
+ params.Op1 = (vcpu->arch.hsr >> 16) & 0xf;
+ params.Op2 = 0;
+ params.Rt2 = (vcpu->arch.hsr >> 10) & 0xf;
+ params.CRn = 0;
+
+ return emulate_cp15(vcpu, ¶ms);
+}
+
+static void reset_coproc_regs(struct kvm_vcpu *vcpu,
+ const struct coproc_reg *table, size_t num)
+{
+ unsigned long i;
+
+ for (i = 0; i < num; i++)
+ if (table[i].reset)
+ table[i].reset(vcpu, &table[i]);
+}
+
+/**
+ * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access
+ * @vcpu: The VCPU pointer
+ * @run: The kvm_run struct
+ */
+int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ struct coproc_params params;
+
+ params.CRm = (vcpu->arch.hsr >> 1) & 0xf;
+ params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf;
+ params.is_write = ((vcpu->arch.hsr & 1) == 0);
+ params.is_64bit = false;
+
+ params.CRn = (vcpu->arch.hsr >> 10) & 0xf;
+ params.Op1 = (vcpu->arch.hsr >> 14) & 0x7;
+ params.Op2 = (vcpu->arch.hsr >> 17) & 0x7;
+ params.Rt2 = 0;
+
+ return emulate_cp15(vcpu, ¶ms);
+}
+
+void kvm_coproc_table_init(void)
+{
+ unsigned int i;
+
+ /* Make sure tables are unique and in order. */
+ for (i = 1; i < ARRAY_SIZE(cp15_regs); i++)
+ BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0);
+}
+
+/**
+ * kvm_reset_coprocs - sets cp15 registers to reset value
+ * @vcpu: The VCPU pointer
+ *
+ * This function finds the right table above and sets the registers on the
+ * virtual CPU struct to their architecturally defined reset values.
+ */
void kvm_reset_coprocs(struct kvm_vcpu *vcpu)
{
+ size_t num;
+ const struct coproc_reg *table;
+
+ /* Catch someone adding a register without putting in reset entry. */
+ memset(vcpu->arch.cp15, 0x42, sizeof(vcpu->arch.cp15));
+
+ /* Generic chip reset first (so target could override). */
+ reset_coproc_regs(vcpu, cp15_regs, ARRAY_SIZE(cp15_regs));
+
+ table = get_target_table(vcpu->arch.target, &num);
+ reset_coproc_regs(vcpu, table, num);
+
+ for (num = 1; num < NR_CP15_REGS; num++)
+ if (vcpu->arch.cp15[num] == 0x42424242)
+ panic("Didn't reset vcpu->arch.cp15[%zi]", num);
}
diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h
new file mode 100644
index 0000000..992adfa
--- /dev/null
+++ b/arch/arm/kvm/coproc.h
@@ -0,0 +1,153 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Authors: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_COPROC_LOCAL_H__
+#define __ARM_KVM_COPROC_LOCAL_H__
+
+struct coproc_params {
+ unsigned long CRn;
+ unsigned long CRm;
+ unsigned long Op1;
+ unsigned long Op2;
+ unsigned long Rt1;
+ unsigned long Rt2;
+ bool is_64bit;
+ bool is_write;
+};
+
+struct coproc_reg {
+ /* MRC/MCR/MRRC/MCRR instruction which accesses it. */
+ unsigned long CRn;
+ unsigned long CRm;
+ unsigned long Op1;
+ unsigned long Op2;
+
+ bool is_64;
+
+ /* Trapped access from guest, if non-NULL. */
+ bool (*access)(struct kvm_vcpu *,
+ const struct coproc_params *,
+ const struct coproc_reg *);
+
+ /* Initialization for vcpu. */
+ void (*reset)(struct kvm_vcpu *, const struct coproc_reg *);
+
+ /* Index into vcpu->arch.cp15[], or 0 if we don't need to save it. */
+ unsigned long reg;
+
+ /* Value (usually reset value) */
+ u64 val;
+};
+
+static inline void print_cp_instr(const struct coproc_params *p)
+{
+ /* Look, we even formatted it for you to paste into the table! */
+ if (p->is_64bit) {
+ kvm_pr_unimpl(" { CRm(%2lu), Op1(%2lu), is64, func_%s },\n",
+ p->CRm, p->Op1, p->is_write ? "write" : "read");
+ } else {
+ kvm_pr_unimpl(" { CRn(%2lu), CRm(%2lu), Op1(%2lu), Op2(%2lu), is32,"
+ " func_%s },\n",
+ p->CRn, p->CRm, p->Op1, p->Op2,
+ p->is_write ? "write" : "read");
+ }
+}
+
+static inline bool ignore_write(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p)
+{
+ return true;
+}
+
+static inline bool read_zero(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p)
+{
+ *vcpu_reg(vcpu, p->Rt1) = 0;
+ return true;
+}
+
+static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
+ const struct coproc_params *params)
+{
+ kvm_debug("CP15 write to read-only register at: %08x\n",
+ *vcpu_pc(vcpu));
+ print_cp_instr(params);
+ return false;
+}
+
+static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
+ const struct coproc_params *params)
+{
+ kvm_debug("CP15 read to write-only register at: %08x\n",
+ *vcpu_pc(vcpu));
+ print_cp_instr(params);
+ return false;
+}
+
+/* Reset functions */
+static inline void reset_unknown(struct kvm_vcpu *vcpu,
+ const struct coproc_reg *r)
+{
+ BUG_ON(!r->reg);
+ BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15));
+ vcpu->arch.cp15[r->reg] = 0xdecafbad;
+}
+
+static inline void reset_val(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
+{
+ BUG_ON(!r->reg);
+ BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15));
+ vcpu->arch.cp15[r->reg] = r->val;
+}
+
+static inline void reset_unknown64(struct kvm_vcpu *vcpu,
+ const struct coproc_reg *r)
+{
+ BUG_ON(!r->reg);
+ BUG_ON(r->reg + 1 >= ARRAY_SIZE(vcpu->arch.cp15));
+
+ vcpu->arch.cp15[r->reg] = 0xdecafbad;
+ vcpu->arch.cp15[r->reg+1] = 0xd0c0ffee;
+}
+
+static inline int cmp_reg(const struct coproc_reg *i1,
+ const struct coproc_reg *i2)
+{
+ BUG_ON(i1 == i2);
+ if (!i1)
+ return 1;
+ else if (!i2)
+ return -1;
+ if (i1->CRn != i2->CRn)
+ return i1->CRn - i2->CRn;
+ if (i1->CRm != i2->CRm)
+ return i1->CRm - i2->CRm;
+ if (i1->Op1 != i2->Op1)
+ return i1->Op1 - i2->Op1;
+ return i1->Op2 - i2->Op2;
+}
+
+
+#define CRn(_x) .CRn = _x
+#define CRm(_x) .CRm = _x
+#define Op1(_x) .Op1 = _x
+#define Op2(_x) .Op2 = _x
+#define is64 .is_64 = true
+#define is32 .is_64 = false
+
+#endif /* __ARM_KVM_COPROC_LOCAL_H__ */
diff --git a/arch/arm/kvm/coproc_a15.c b/arch/arm/kvm/coproc_a15.c
new file mode 100644
index 0000000..55cb4a3
--- /dev/null
+++ b/arch/arm/kvm/coproc_a15.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Authors: Rusty Russell <rusty@rustcorp.au>
+ * Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include <linux/kvm_host.h>
+#include <asm/cputype.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_host.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_coproc.h>
+#include <linux/init.h>
+
+#define MPIDR_CPUID 0x3
+
+static void reset_mpidr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
+{
+ /*
+ * Compute guest MPIDR:
+ * (Even if we present only one VCPU to the guest on an SMP
+ * host we don't set the U bit in the MPIDR, or vice versa, as
+ * revealing the underlying hardware properties is likely to
+ * be the best choice).
+ */
+ vcpu->arch.cp15[c0_MPIDR] = (read_cpuid_mpidr() & ~MPIDR_CPUID)
+ | (vcpu->vcpu_id & MPIDR_CPUID);
+}
+
+#include "coproc.h"
+
+/* A15 TRM 4.3.28: RO WI */
+static bool access_actlr(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ if (p->is_write)
+ return ignore_write(vcpu, p);
+
+ *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c1_ACTLR];
+ return true;
+}
+
+/* A15 TRM 4.3.60: R/O. */
+static bool access_cbar(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ if (p->is_write)
+ return write_to_read_only(vcpu, p);
+ return read_zero(vcpu, p);
+}
+
+/* A15 TRM 4.3.48: R/O WI. */
+static bool access_l2ctlr(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ if (p->is_write)
+ return ignore_write(vcpu, p);
+
+ *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c9_L2CTLR];
+ return true;
+}
+
+static void reset_l2ctlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
+{
+ u32 l2ctlr, ncores;
+
+ asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r" (l2ctlr));
+ l2ctlr &= ~(3 << 24);
+ ncores = atomic_read(&vcpu->kvm->online_vcpus) - 1;
+ l2ctlr |= (ncores & 3) << 24;
+
+ vcpu->arch.cp15[c9_L2CTLR] = l2ctlr;
+}
+
+static void reset_actlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r)
+{
+ u32 actlr;
+
+ /* ACTLR contains SMP bit: make sure you create all cpus first! */
+ asm volatile("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
+ /* Make the SMP bit consistent with the guest configuration */
+ if (atomic_read(&vcpu->kvm->online_vcpus) > 1)
+ actlr |= 1U << 6;
+ else
+ actlr &= ~(1U << 6);
+
+ vcpu->arch.cp15[c1_ACTLR] = actlr;
+}
+
+/* A15 TRM 4.3.49: R/O WI (even if NSACR.NS_L2ERR, a write of 1 is ignored). */
+static bool access_l2ectlr(struct kvm_vcpu *vcpu,
+ const struct coproc_params *p,
+ const struct coproc_reg *r)
+{
+ if (p->is_write)
+ return ignore_write(vcpu, p);
+
+ *vcpu_reg(vcpu, p->Rt1) = 0;
+ return true;
+}
+
+/*
+ * A15-specific CP15 registers.
+ * Important: Must be sorted ascending by CRn, CRM, Op1, Op2
+ */
+static const struct coproc_reg a15_regs[] = {
+ /* MPIDR: we use VMPIDR for guest access. */
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 5), is32,
+ NULL, reset_mpidr, c0_MPIDR },
+
+ /* SCTLR: swapped by interrupt.S. */
+ { CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32,
+ NULL, reset_val, c1_SCTLR, 0x00C50078 },
+ /* ACTLR: trapped by HCR.TAC bit. */
+ { CRn( 1), CRm( 0), Op1( 0), Op2( 1), is32,
+ access_actlr, reset_actlr, c1_ACTLR },
+ /* CPACR: swapped by interrupt.S. */
+ { CRn( 1), CRm( 0), Op1( 0), Op2( 2), is32,
+ NULL, reset_val, c1_CPACR, 0x00000000 },
+
+ /*
+ * L2CTLR access (guest wants to know #CPUs).
+ */
+ { CRn( 9), CRm( 0), Op1( 1), Op2( 2), is32,
+ access_l2ctlr, reset_l2ctlr, c9_L2CTLR },
+ { CRn( 9), CRm( 0), Op1( 1), Op2( 3), is32, access_l2ectlr},
+
+ /* The Configuration Base Address Register. */
+ { CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar},
+};
+
+static struct kvm_coproc_target_table a15_target_table = {
+ .target = KVM_ARM_TARGET_CORTEX_A15,
+ .table = a15_regs,
+ .num = ARRAY_SIZE(a15_regs),
+};
+
+static int __init coproc_a15_init(void)
+{
+ unsigned int i;
+
+ for (i = 1; i < ARRAY_SIZE(a15_regs); i++)
+ BUG_ON(cmp_reg(&a15_regs[i-1],
+ &a15_regs[i]) >= 0);
+
+ kvm_register_target_coproc_table(&a15_target_table);
+ return 0;
+}
+late_initcall(coproc_a15_init);
diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
index 4e25b65..546cdaf 100644
--- a/arch/arm/kvm/emulate.c
+++ b/arch/arm/kvm/emulate.c
@@ -16,7 +16,13 @@
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
+#include <linux/mm.h>
+#include <linux/kvm_host.h>
+#include <asm/kvm_arm.h>
#include <asm/kvm_emulate.h>
+#include <trace/events/kvm.h>
+
+#include "trace.h"
#define VCPU_NR_MODES 6
#define REG_OFFSET(_reg) \
@@ -149,3 +155,215 @@ u32 *vcpu_spsr(struct kvm_vcpu *vcpu)
BUG();
}
}
+
+/**
+ * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest
+ * @vcpu: the vcpu pointer
+ * @run: the kvm_run structure pointer
+ *
+ * Simply sets the wait_for_interrupts flag on the vcpu structure, which will
+ * halt execution of world-switches and schedule other host processes until
+ * there is an incoming IRQ or FIQ to the VM.
+ */
+int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ trace_kvm_wfi(*vcpu_pc(vcpu));
+ kvm_vcpu_block(vcpu);
+ return 1;
+}
+
+/**
+ * adjust_itstate - adjust ITSTATE when emulating instructions in IT-block
+ * @vcpu: The VCPU pointer
+ *
+ * When exceptions occur while instructions are executed in Thumb IF-THEN
+ * blocks, the ITSTATE field of the CPSR is not advanved (updated), so we have
+ * to do this little bit of work manually. The fields map like this:
+ *
+ * IT[7:0] -> CPSR[26:25],CPSR[15:10]
+ */
+static void kvm_adjust_itstate(struct kvm_vcpu *vcpu)
+{
+ unsigned long itbits, cond;
+ unsigned long cpsr = *vcpu_cpsr(vcpu);
+ bool is_arm = !(cpsr & PSR_T_BIT);
+
+ BUG_ON(is_arm && (cpsr & PSR_IT_MASK));
+
+ if (!(cpsr & PSR_IT_MASK))
+ return;
+
+ cond = (cpsr & 0xe000) >> 13;
+ itbits = (cpsr & 0x1c00) >> (10 - 2);
+ itbits |= (cpsr & (0x3 << 25)) >> 25;
+
+ /* Perform ITAdvance (see page A-52 in ARM DDI 0406C) */
+ if ((itbits & 0x7) == 0)
+ itbits = cond = 0;
+ else
+ itbits = (itbits << 1) & 0x1f;
+
+ cpsr &= ~PSR_IT_MASK;
+ cpsr |= cond << 13;
+ cpsr |= (itbits & 0x1c) << (10 - 2);
+ cpsr |= (itbits & 0x3) << 25;
+ *vcpu_cpsr(vcpu) = cpsr;
+}
+
+/**
+ * kvm_skip_instr - skip a trapped instruction and proceed to the next
+ * @vcpu: The vcpu pointer
+ */
+void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
+{
+ bool is_thumb;
+
+ is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_T_BIT);
+ if (is_thumb && !is_wide_instr)
+ *vcpu_pc(vcpu) += 2;
+ else
+ *vcpu_pc(vcpu) += 4;
+ kvm_adjust_itstate(vcpu);
+}
+
+
+/******************************************************************************
+ * Inject exceptions into the guest
+ */
+
+static u32 exc_vector_base(struct kvm_vcpu *vcpu)
+{
+ u32 sctlr = vcpu->arch.cp15[c1_SCTLR];
+ u32 vbar = vcpu->arch.cp15[c12_VBAR];
+
+ if (sctlr & SCTLR_V)
+ return 0xffff0000;
+ else /* always have security exceptions */
+ return vbar;
+}
+
+/**
+ * kvm_inject_undefined - inject an undefined exception into the guest
+ * @vcpu: The VCPU to receive the undefined exception
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ *
+ * Modelled after TakeUndefInstrException() pseudocode.
+ */
+void kvm_inject_undefined(struct kvm_vcpu *vcpu)
+{
+ u32 new_lr_value;
+ u32 new_spsr_value;
+ u32 cpsr = *vcpu_cpsr(vcpu);
+ u32 sctlr = vcpu->arch.cp15[c1_SCTLR];
+ bool is_thumb = (cpsr & PSR_T_BIT);
+ u32 vect_offset = 4;
+ u32 return_offset = (is_thumb) ? 2 : 4;
+
+ new_spsr_value = cpsr;
+ new_lr_value = *vcpu_pc(vcpu) - return_offset;
+
+ *vcpu_cpsr(vcpu) = (cpsr & ~MODE_MASK) | UND_MODE;
+ *vcpu_cpsr(vcpu) |= PSR_I_BIT;
+ *vcpu_cpsr(vcpu) &= ~(PSR_IT_MASK | PSR_J_BIT | PSR_E_BIT | PSR_T_BIT);
+
+ if (sctlr & SCTLR_TE)
+ *vcpu_cpsr(vcpu) |= PSR_T_BIT;
+ if (sctlr & SCTLR_EE)
+ *vcpu_cpsr(vcpu) |= PSR_E_BIT;
+
+ /* Note: These now point to UND banked copies */
+ *vcpu_spsr(vcpu) = cpsr;
+ *vcpu_reg(vcpu, 14) = new_lr_value;
+
+ /* Branch to exception vector */
+ *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset;
+}
+
+/*
+ * Modelled after TakeDataAbortException() and TakePrefetchAbortException
+ * pseudocode.
+ */
+static void inject_abt(struct kvm_vcpu *vcpu, bool is_pabt, unsigned long addr)
+{
+ u32 new_lr_value;
+ u32 new_spsr_value;
+ u32 cpsr = *vcpu_cpsr(vcpu);
+ u32 sctlr = vcpu->arch.cp15[c1_SCTLR];
+ bool is_thumb = (cpsr & PSR_T_BIT);
+ u32 vect_offset;
+ u32 return_offset = (is_thumb) ? 4 : 0;
+ bool is_lpae;
+
+ new_spsr_value = cpsr;
+ new_lr_value = *vcpu_pc(vcpu) + return_offset;
+
+ *vcpu_cpsr(vcpu) = (cpsr & ~MODE_MASK) | ABT_MODE;
+ *vcpu_cpsr(vcpu) |= PSR_I_BIT | PSR_A_BIT;
+ *vcpu_cpsr(vcpu) &= ~(PSR_IT_MASK | PSR_J_BIT | PSR_E_BIT | PSR_T_BIT);
+
+ if (sctlr & SCTLR_TE)
+ *vcpu_cpsr(vcpu) |= PSR_T_BIT;
+ if (sctlr & SCTLR_EE)
+ *vcpu_cpsr(vcpu) |= PSR_E_BIT;
+
+ /* Note: These now point to ABT banked copies */
+ *vcpu_spsr(vcpu) = cpsr;
+ *vcpu_reg(vcpu, 14) = new_lr_value;
+
+ if (is_pabt)
+ vect_offset = 12;
+ else
+ vect_offset = 16;
+
+ /* Branch to exception vector */
+ *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset;
+
+ if (is_pabt) {
+ /* Set DFAR and DFSR */
+ vcpu->arch.cp15[c6_IFAR] = addr;
+ is_lpae = (vcpu->arch.cp15[c2_TTBCR] >> 31);
+ /* Always give debug fault for now - should give guest a clue */
+ if (is_lpae)
+ vcpu->arch.cp15[c5_IFSR] = 1 << 9 | 0x22;
+ else
+ vcpu->arch.cp15[c5_IFSR] = 2;
+ } else { /* !iabt */
+ /* Set DFAR and DFSR */
+ vcpu->arch.cp15[c6_DFAR] = addr;
+ is_lpae = (vcpu->arch.cp15[c2_TTBCR] >> 31);
+ /* Always give debug fault for now - should give guest a clue */
+ if (is_lpae)
+ vcpu->arch.cp15[c5_DFSR] = 1 << 9 | 0x22;
+ else
+ vcpu->arch.cp15[c5_DFSR] = 2;
+ }
+
+}
+
+/**
+ * kvm_inject_dabt - inject a data abort into the guest
+ * @vcpu: The VCPU to receive the undefined exception
+ * @addr: The address to report in the DFAR
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr)
+{
+ inject_abt(vcpu, false, addr);
+}
+
+/**
+ * kvm_inject_pabt - inject a prefetch abort into the guest
+ * @vcpu: The VCPU to receive the undefined exception
+ * @addr: The address to report in the DFAR
+ *
+ * It is assumed that this code is called from the VCPU thread and that the
+ * VCPU therefore is not currently executing guest code.
+ */
+void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr)
+{
+ inject_abt(vcpu, true, addr);
+}
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index 105d1f7..c86a513 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -64,6 +64,51 @@ TRACE_EVENT(kvm_irq_line,
__entry->type, __entry->vcpu_idx, __entry->irq_num, __entry->level)
);
+/* Architecturally implementation defined CP15 register access */
+TRACE_EVENT(kvm_emulate_cp15_imp,
+ TP_PROTO(unsigned long Op1, unsigned long Rt1, unsigned long CRn,
+ unsigned long CRm, unsigned long Op2, bool is_write),
+ TP_ARGS(Op1, Rt1, CRn, CRm, Op2, is_write),
+
+ TP_STRUCT__entry(
+ __field( unsigned int, Op1 )
+ __field( unsigned int, Rt1 )
+ __field( unsigned int, CRn )
+ __field( unsigned int, CRm )
+ __field( unsigned int, Op2 )
+ __field( bool, is_write )
+ ),
+
+ TP_fast_assign(
+ __entry->is_write = is_write;
+ __entry->Op1 = Op1;
+ __entry->Rt1 = Rt1;
+ __entry->CRn = CRn;
+ __entry->CRm = CRm;
+ __entry->Op2 = Op2;
+ ),
+
+ TP_printk("Implementation defined CP15: %s\tp15, %u, r%u, c%u, c%u, %u",
+ (__entry->is_write) ? "mcr" : "mrc",
+ __entry->Op1, __entry->Rt1, __entry->CRn,
+ __entry->CRm, __entry->Op2)
+);
+
+TRACE_EVENT(kvm_wfi,
+ TP_PROTO(unsigned long vcpu_pc),
+ TP_ARGS(vcpu_pc),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ ),
+
+ TP_printk("guest executed wfi at: 0x%08lx", __entry->vcpu_pc)
+);
+
TRACE_EVENT(kvm_unmap_hva,
TP_PROTO(unsigned long hva),
TP_ARGS(hva),
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 10/14] KVM: ARM: User space API for getting/setting co-proc registers
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (8 preceding siblings ...)
2012-10-22 6:50 ` [PATCH v3 09/14] KVM: ARM: Emulation framework and CP15 emulation Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 11/14] KVM: ARM: Demux CCSIDR in the userspace API Christoffer Dall
` (3 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
The following three ioctls are implemented:
- KVM_GET_REG_LIST
- KVM_GET_ONE_REG
- KVM_SET_ONE_REG
Now we have a table for all the cp15 registers, we can drive a generic
API.
The register IDs carry the following encoding:
ARM registers are mapped using the lower 32 bits. The upper 16 of that
is the register group type, or coprocessor number:
ARM 32-bit CP15 registers have the following id bit patterns:
0x4002 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>
ARM 64-bit CP15 registers have the following id bit patterns:
0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
For futureproofing, we need to tell QEMU about the CP15 registers the
host lets the guest access.
It will need this information to restore a current guest on a future
CPU or perhaps a future KVM which allow some of these to be changed.
We use a separate table for these, as they're only for the userspace API.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
Documentation/virtual/kvm/api.txt | 44 +++++
arch/arm/include/asm/kvm_coproc.h | 9 +
arch/arm/include/asm/kvm_host.h | 4
arch/arm/kvm/coproc.c | 327 +++++++++++++++++++++++++++++++++++++
arch/arm/kvm/guest.c | 9 +
5 files changed, 389 insertions(+), 4 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 4514292..242ff3e 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1798,6 +1798,11 @@ is the register group type, or coprocessor number:
ARM core registers have the following id bit patterns:
0x4002 0000 0010 <index into the kvm_regs struct:16>
+ARM 32-bit CP15 registers have the following id bit patterns:
+ 0x4002 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>
+
+ARM 64-bit CP15 registers have the following id bit patterns:
+ 0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
4.69 KVM_GET_ONE_REG
@@ -2139,6 +2144,45 @@ This ioctl returns the guest registers that are supported for the
KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
+4.77 KVM_ARM_VCPU_INIT
+
+Capability: basic
+Architectures: arm
+Type: vcpu ioctl
+Parameters: struct struct kvm_vcpu_init (in)
+Returns: 0 on success; -1 on error
+Errors:
+ ?EINVAL: ???the target is unknown, or the combination of features is invalid.
+ ?ENOENT: ???a features bit specified is unknown.
+
+This tells KVM what type of CPU to present to the guest, and what
+optional features it should have. ?This will cause a reset of the cpu
+registers to their initial values. ?If this is not called, KVM_RUN will
+return ENOEXEC for that vcpu.
+
+Note that because some registers reflect machine topology, all vcpus
+should be created before this ioctl is invoked.
+
+4.78 KVM_GET_REG_LIST
+
+Capability: basic
+Architectures: arm
+Type: vcpu ioctl
+Parameters: struct kvm_reg_list (in/out)
+Returns: 0 on success; -1 on error
+Errors:
+ ?E2BIG: ????the reg index list is too big to fit in the array specified by
+ ????????????the user (the number required will be written into n).
+
+struct kvm_reg_list {
+ __u64 n; /* number of registers in reg[] */
+ __u64 reg[0];
+};
+
+This ioctl returns the guest registers that are supported for the
+KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
+
+
5. The kvm_run structure
------------------------
diff --git a/arch/arm/include/asm/kvm_coproc.h b/arch/arm/include/asm/kvm_coproc.h
index bd1ace0..4917c2f 100644
--- a/arch/arm/include/asm/kvm_coproc.h
+++ b/arch/arm/include/asm/kvm_coproc.h
@@ -34,5 +34,14 @@ int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run);
+
+unsigned long kvm_arm_num_guest_msrs(struct kvm_vcpu *vcpu);
+int kvm_arm_copy_msrindices(struct kvm_vcpu *vcpu, u64 __user *uindices);
void kvm_coproc_table_init(void);
+
+struct kvm_one_reg;
+int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices);
+int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
+int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *);
+unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu);
#endif /* __ARM_KVM_COPROC_H__ */
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 2ce654c..606e21a 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -27,6 +27,7 @@
#define KVM_MEMORY_SLOTS 32
#define KVM_PRIVATE_MEM_SLOTS 4
#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
+#define KVM_HAVE_ONE_REG
#define KVM_VCPU_MAX_FEATURES 0
@@ -139,6 +140,9 @@ int kvm_unmap_hva_range(struct kvm *kvm,
unsigned long start, unsigned long end);
void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
+unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
+int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
+
/* We do not have shadow page tables, hence the empty hooks */
static inline int kvm_age_hva(struct kvm *kvm, unsigned long hva)
{
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 722efe3..95a0f5e 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -18,6 +18,7 @@
*/
#include <linux/mm.h>
#include <linux/kvm_host.h>
+#include <linux/uaccess.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_host.h>
#include <asm/kvm_emulate.h>
@@ -347,6 +348,328 @@ int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
return emulate_cp15(vcpu, ¶ms);
}
+/******************************************************************************
+ * Userspace API
+ *****************************************************************************/
+
+static bool index_to_params(u64 id, struct coproc_params *params)
+{
+ switch (id & KVM_REG_SIZE_MASK) {
+ case KVM_REG_SIZE_U32:
+ /* Any unused index bits means it's not valid. */
+ if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
+ | KVM_REG_ARM_COPROC_MASK
+ | KVM_REG_ARM_32_CRN_MASK
+ | KVM_REG_ARM_CRM_MASK
+ | KVM_REG_ARM_OPC1_MASK
+ | KVM_REG_ARM_32_OPC2_MASK))
+ return false;
+
+ params->is_64bit = false;
+ params->CRn = ((id & KVM_REG_ARM_32_CRN_MASK)
+ >> KVM_REG_ARM_32_CRN_SHIFT);
+ params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
+ >> KVM_REG_ARM_CRM_SHIFT);
+ params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
+ >> KVM_REG_ARM_OPC1_SHIFT);
+ params->Op2 = ((id & KVM_REG_ARM_32_OPC2_MASK)
+ >> KVM_REG_ARM_32_OPC2_SHIFT);
+ return true;
+ case KVM_REG_SIZE_U64:
+ /* Any unused index bits means it's not valid. */
+ if (id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK
+ | KVM_REG_ARM_COPROC_MASK
+ | KVM_REG_ARM_CRM_MASK
+ | KVM_REG_ARM_OPC1_MASK))
+ return false;
+ params->is_64bit = true;
+ params->CRm = ((id & KVM_REG_ARM_CRM_MASK)
+ >> KVM_REG_ARM_CRM_SHIFT);
+ params->Op1 = ((id & KVM_REG_ARM_OPC1_MASK)
+ >> KVM_REG_ARM_OPC1_SHIFT);
+ params->Op2 = 0;
+ params->CRn = 0;
+ return true;
+ default:
+ return false;
+ }
+}
+
+/* Decode an index value, and find the cp15 coproc_reg entry. */
+static const struct coproc_reg *index_to_coproc_reg(struct kvm_vcpu *vcpu,
+ u64 id)
+{
+ size_t num;
+ const struct coproc_reg *table, *r;
+ struct coproc_params params;
+
+ /* We only do cp15 for now. */
+ if ((id & KVM_REG_ARM_COPROC_MASK) >> KVM_REG_ARM_COPROC_SHIFT != 15)
+ return NULL;
+
+ if (!index_to_params(id, ¶ms))
+ return NULL;
+
+ table = get_target_table(vcpu->arch.target, &num);
+ r = find_reg(¶ms, table, num);
+ if (!r)
+ r = find_reg(¶ms, cp15_regs, ARRAY_SIZE(cp15_regs));
+
+ /* Not saved in the cp15 array? */
+ if (r && !r->reg)
+ r = NULL;
+
+ return r;
+}
+
+/*
+ * These are the invariant cp15 registers: we let the guest see the host
+ * versions of these, so they're part of the guest state.
+ *
+ * A future CPU may provide a mechanism to present different values to
+ * the guest, or a future kvm may trap them.
+ */
+/* Unfortunately, there's no register-argument for mrc, so generate. */
+#define FUNCTION_FOR32(crn, crm, op1, op2, name) \
+ static void get_##name(struct kvm_vcpu *v, \
+ const struct coproc_reg *r) \
+ { \
+ u32 val; \
+ \
+ asm volatile("mrc p15, " __stringify(op1) \
+ ", %0, c" __stringify(crn) \
+ ", c" __stringify(crm) \
+ ", " __stringify(op2) "\n" : "=r" (val)); \
+ ((struct coproc_reg *)r)->val = val; \
+ }
+
+FUNCTION_FOR32(0, 0, 0, 0, MIDR)
+FUNCTION_FOR32(0, 0, 0, 1, CTR)
+FUNCTION_FOR32(0, 0, 0, 2, TCMTR)
+FUNCTION_FOR32(0, 0, 0, 3, TLBTR)
+FUNCTION_FOR32(0, 0, 0, 6, REVIDR)
+FUNCTION_FOR32(0, 1, 0, 0, ID_PFR0)
+FUNCTION_FOR32(0, 1, 0, 1, ID_PFR1)
+FUNCTION_FOR32(0, 1, 0, 2, ID_DFR0)
+FUNCTION_FOR32(0, 1, 0, 3, ID_AFR0)
+FUNCTION_FOR32(0, 1, 0, 4, ID_MMFR0)
+FUNCTION_FOR32(0, 1, 0, 5, ID_MMFR1)
+FUNCTION_FOR32(0, 1, 0, 6, ID_MMFR2)
+FUNCTION_FOR32(0, 1, 0, 7, ID_MMFR3)
+FUNCTION_FOR32(0, 2, 0, 0, ID_ISAR0)
+FUNCTION_FOR32(0, 2, 0, 1, ID_ISAR1)
+FUNCTION_FOR32(0, 2, 0, 2, ID_ISAR2)
+FUNCTION_FOR32(0, 2, 0, 3, ID_ISAR3)
+FUNCTION_FOR32(0, 2, 0, 4, ID_ISAR4)
+FUNCTION_FOR32(0, 2, 0, 5, ID_ISAR5)
+FUNCTION_FOR32(0, 0, 1, 1, CLIDR)
+FUNCTION_FOR32(0, 0, 1, 7, AIDR)
+
+/* ->val is filled in by kvm_invariant_coproc_table_init() */
+static struct coproc_reg invariant_cp15[] = {
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 0), is32, NULL, get_MIDR },
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 1), is32, NULL, get_CTR },
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 2), is32, NULL, get_TCMTR },
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 3), is32, NULL, get_TLBTR },
+ { CRn( 0), CRm( 0), Op1( 0), Op2( 6), is32, NULL, get_REVIDR },
+
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 0), is32, NULL, get_ID_PFR0 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 1), is32, NULL, get_ID_PFR1 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 2), is32, NULL, get_ID_DFR0 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 3), is32, NULL, get_ID_AFR0 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 4), is32, NULL, get_ID_MMFR0 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 5), is32, NULL, get_ID_MMFR1 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 6), is32, NULL, get_ID_MMFR2 },
+ { CRn( 0), CRm( 1), Op1( 0), Op2( 7), is32, NULL, get_ID_MMFR3 },
+
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 0), is32, NULL, get_ID_ISAR0 },
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 1), is32, NULL, get_ID_ISAR1 },
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 2), is32, NULL, get_ID_ISAR2 },
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 3), is32, NULL, get_ID_ISAR3 },
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 4), is32, NULL, get_ID_ISAR4 },
+ { CRn( 0), CRm( 2), Op1( 0), Op2( 5), is32, NULL, get_ID_ISAR5 },
+
+ { CRn( 0), CRm( 0), Op1( 1), Op2( 1), is32, NULL, get_CLIDR },
+ { CRn( 0), CRm( 0), Op1( 1), Op2( 7), is32, NULL, get_AIDR },
+};
+
+static int reg_from_user(void *val, const void __user *uaddr, u64 id)
+{
+ /* This Just Works because we are little endian. */
+ if (copy_from_user(val, uaddr, KVM_REG_SIZE(id)) != 0)
+ return -EFAULT;
+ return 0;
+}
+
+static int reg_to_user(void __user *uaddr, const void *val, u64 id)
+{
+ /* This Just Works because we are little endian. */
+ if (copy_to_user(uaddr, val, KVM_REG_SIZE(id)) != 0)
+ return -EFAULT;
+ return 0;
+}
+
+static int get_invariant_cp15(u64 id, void __user *uaddr)
+{
+ struct coproc_params params;
+ const struct coproc_reg *r;
+
+ if (!index_to_params(id, ¶ms))
+ return -ENOENT;
+
+ r = find_reg(¶ms, invariant_cp15, ARRAY_SIZE(invariant_cp15));
+ if (!r)
+ return -ENOENT;
+
+ return reg_to_user(uaddr, &r->val, id);
+}
+
+static int set_invariant_cp15(u64 id, void __user *uaddr)
+{
+ struct coproc_params params;
+ const struct coproc_reg *r;
+ int err;
+ u64 val = 0; /* Make sure high bits are 0 for 32-bit regs */
+
+ if (!index_to_params(id, ¶ms))
+ return -ENOENT;
+ r = find_reg(¶ms, invariant_cp15, ARRAY_SIZE(invariant_cp15));
+ if (!r)
+ return -ENOENT;
+
+ err = reg_from_user(&val, uaddr, id);
+ if (err)
+ return err;
+
+ /* This is what we mean by invariant: you can't change it. */
+ if (r->val != val)
+ return -EINVAL;
+
+ return 0;
+}
+
+int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ const struct coproc_reg *r;
+ void __user *uaddr = (void __user *)(long)reg->addr;
+
+ r = index_to_coproc_reg(vcpu, reg->id);
+ if (!r)
+ return get_invariant_cp15(reg->id, uaddr);
+
+ /* Note: copies two regs if size is 64 bit. */
+ return reg_to_user(uaddr, &vcpu->arch.cp15[r->reg], reg->id);
+}
+
+int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+{
+ const struct coproc_reg *r;
+ void __user *uaddr = (void __user *)(long)reg->addr;
+
+ r = index_to_coproc_reg(vcpu, reg->id);
+ if (!r)
+ return set_invariant_cp15(reg->id, uaddr);
+
+ /* Note: copies two regs if size is 64 bit */
+ return reg_from_user(&vcpu->arch.cp15[r->reg], uaddr, reg->id);
+}
+
+static u64 cp15_to_index(const struct coproc_reg *reg)
+{
+ u64 val = KVM_REG_ARM | (15 << KVM_REG_ARM_COPROC_SHIFT);
+ if (reg->is_64) {
+ val |= KVM_REG_SIZE_U64;
+ val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
+ val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
+ } else {
+ val |= KVM_REG_SIZE_U32;
+ val |= (reg->Op1 << KVM_REG_ARM_OPC1_SHIFT);
+ val |= (reg->Op2 << KVM_REG_ARM_32_OPC2_SHIFT);
+ val |= (reg->CRm << KVM_REG_ARM_CRM_SHIFT);
+ val |= (reg->CRn << KVM_REG_ARM_32_CRN_SHIFT);
+ }
+ return val;
+}
+
+static bool copy_reg_to_user(const struct coproc_reg *reg, u64 __user **uind)
+{
+ if (!*uind)
+ return true;
+
+ if (put_user(cp15_to_index(reg), *uind))
+ return false;
+
+ (*uind)++;
+ return true;
+}
+
+/* Assumed ordered tables, see kvm_coproc_table_init. */
+static int walk_cp15(struct kvm_vcpu *vcpu, u64 __user *uind)
+{
+ const struct coproc_reg *i1, *i2, *end1, *end2;
+ unsigned int total = 0;
+ size_t num;
+
+ /* We check for duplicates here, to allow arch-specific overrides. */
+ i1 = get_target_table(vcpu->arch.target, &num);
+ end1 = i1 + num;
+ i2 = cp15_regs;
+ end2 = cp15_regs + ARRAY_SIZE(cp15_regs);
+
+ BUG_ON(i1 == end1 || i2 == end2);
+
+ /* Walk carefully, as both tables may refer to the same register. */
+ while (i1 || i2) {
+ int cmp = cmp_reg(i1, i2);
+ /* target-specific overrides generic entry. */
+ if (cmp <= 0) {
+ /* Ignore registers we trap but don't save. */
+ if (i1->reg) {
+ if (!copy_reg_to_user(i1, &uind))
+ return -EFAULT;
+ total++;
+ }
+ } else {
+ /* Ignore registers we trap but don't save. */
+ if (i2->reg) {
+ if (!copy_reg_to_user(i2, &uind))
+ return -EFAULT;
+ total++;
+ }
+ }
+
+ if (cmp <= 0 && ++i1 == end1)
+ i1 = NULL;
+ if (cmp >= 0 && ++i2 == end2)
+ i2 = NULL;
+ }
+ return total;
+}
+
+unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
+{
+ return ARRAY_SIZE(invariant_cp15)
+ + walk_cp15(vcpu, (u64 __user *)NULL);
+}
+
+int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+{
+ unsigned int i;
+ int err;
+
+ /* Then give them all the invariant registers' indices. */
+ for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++) {
+ if (put_user(cp15_to_index(&invariant_cp15[i]), uindices))
+ return -EFAULT;
+ uindices++;
+ }
+
+ err = walk_cp15(vcpu, uindices);
+ if (err > 0)
+ err = 0;
+ return err;
+}
+
void kvm_coproc_table_init(void)
{
unsigned int i;
@@ -354,6 +677,10 @@ void kvm_coproc_table_init(void)
/* Make sure tables are unique and in order. */
for (i = 1; i < ARRAY_SIZE(cp15_regs); i++)
BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0);
+
+ /* We abuse the reset function to overwrite the table itself. */
+ for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++)
+ invariant_cp15[i].reset(NULL, &invariant_cp15[i]);
}
/**
diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
index 4fd0467..de05c557c 100644
--- a/arch/arm/kvm/guest.c
+++ b/arch/arm/kvm/guest.c
@@ -26,6 +26,7 @@
#include <asm/kvm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
+#include <asm/kvm_coproc.h>
#define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
#define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
@@ -119,7 +120,7 @@ static unsigned long num_core_regs(void)
*/
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
{
- return num_core_regs();
+ return num_core_regs() + kvm_arm_num_coproc_regs(vcpu);
}
/**
@@ -138,7 +139,7 @@ int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
uindices++;
}
- return 0;
+ return kvm_arm_copy_coproc_indices(vcpu, uindices);
}
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
@@ -151,7 +152,7 @@ int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
return get_core_reg(vcpu, reg);
- return -EINVAL;
+ return kvm_arm_coproc_get_reg(vcpu, reg);
}
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
@@ -164,7 +165,7 @@ int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
return set_core_reg(vcpu, reg);
- return -EINVAL;
+ return kvm_arm_coproc_set_reg(vcpu, reg);
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 11/14] KVM: ARM: Demux CCSIDR in the userspace API
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (9 preceding siblings ...)
2012-10-22 6:50 ` [PATCH v3 10/14] KVM: ARM: User space API for getting/setting co-proc registers Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 12/14] KVM: ARM: VFP userspace interface Christoffer Dall
` (2 subsequent siblings)
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
The Cache Size Selection Register (CSSELR) selects the current Cache
Size ID Register (CCSIDR). You write which cache you are interested
in to CSSELR, and read the information out of CCSIDR.
Which cache numbers are valid is known by reading the Cache Level ID
Register (CLIDR).
To export this state to userspace, we add a KVM_REG_ARM_DEMUX
numberspace (17), which uses 8 bits to represent which register is
being demultiplexed (0 for CCSIDR), and the lower 8 bits to represent
this demultiplexing (in our case, the CSSELR value, which is 4 bits).
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
---
Documentation/virtual/kvm/api.txt | 2
arch/arm/include/uapi/asm/kvm.h | 9 ++
arch/arm/kvm/coproc.c | 163 ++++++++++++++++++++++++++++++++++++-
3 files changed, 171 insertions(+), 3 deletions(-)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 242ff3e..6f87d61 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1804,6 +1804,8 @@ ARM 32-bit CP15 registers have the following id bit patterns:
ARM 64-bit CP15 registers have the following id bit patterns:
0x4003 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
+ARM CCSIDR registers are demultiplexed by CSSELR value:
+ 0x4002 0000 0011 00 <csselr:8>
4.69 KVM_GET_ONE_REG
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 138a588c..d79d064 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -81,6 +81,15 @@ struct kvm_arch_memory_slot {
#define KVM_REG_ARM_CORE (0x0010 << KVM_REG_ARM_COPROC_SHIFT)
#define KVM_REG_ARM_CORE_REG(name) (offsetof(struct kvm_regs, name) / 4)
+/* Some registers need more space to represent values. */
+#define KVM_REG_ARM_DEMUX (0x0011 << KVM_REG_ARM_COPROC_SHIFT)
+#define KVM_REG_ARM_DEMUX_ID_MASK 0x000000000000FF00
+#define KVM_REG_ARM_DEMUX_ID_SHIFT 8
+#define KVM_REG_ARM_DEMUX_ID_CCSIDR (0x00 << KVM_REG_ARM_DEMUX_ID_SHIFT)
+#define KVM_REG_ARM_DEMUX_VAL_MASK 0x00000000000000FF
+#define KVM_REG_ARM_DEMUX_VAL_SHIFT 0
+
+
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
#define KVM_ARM_IRQ_TYPE_MASK 0xff
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 95a0f5e..9ce5861 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -35,6 +35,12 @@
* Co-processor emulation
*****************************************************************************/
+/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
+static u32 cache_levels;
+
+/* CSSELR values; used to index KVM_REG_ARM_DEMUX_ID_CCSIDR */
+#define CSSELR_MAX 12
+
int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
kvm_inject_undefined(vcpu);
@@ -548,11 +554,112 @@ static int set_invariant_cp15(u64 id, void __user *uaddr)
return 0;
}
+static bool is_valid_cache(u32 val)
+{
+ u32 level, ctype;
+
+ if (val >= CSSELR_MAX)
+ return -ENOENT;
+
+ /* Bottom bit is Instruction or Data bit. Next 3 bits are level. */
+ level = (val >> 1);
+ ctype = (cache_levels >> (level * 3)) & 7;
+
+ switch (ctype) {
+ case 0: /* No cache */
+ return false;
+ case 1: /* Instruction cache only */
+ return (val & 1);
+ case 2: /* Data cache only */
+ case 4: /* Unified cache */
+ return !(val & 1);
+ case 3: /* Separate instruction and data caches */
+ return true;
+ default: /* Reserved: we can't know instruction or data. */
+ return false;
+ }
+}
+
+/* Which cache CCSIDR represents depends on CSSELR value. */
+static u32 get_ccsidr(u32 csselr)
+{
+ u32 ccsidr;
+
+ /* Make sure noone else changes CSSELR during this! */
+ local_irq_disable();
+ /* Put value into CSSELR */
+ asm volatile("mcr p15, 2, %0, c0, c0, 0" : : "r" (csselr));
+ /* Read result out of CCSIDR */
+ asm volatile("mrc p15, 1, %0, c0, c0, 0" : "=r" (ccsidr));
+ local_irq_enable();
+
+ return ccsidr;
+}
+
+static int demux_c15_get(u64 id, void __user *uaddr)
+{
+ u32 val;
+ u32 __user *uval = uaddr;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+ case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+ val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+ >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+ if (!is_valid_cache(val))
+ return -ENOENT;
+
+ return put_user(get_ccsidr(val), uval);
+ default:
+ return -ENOENT;
+ }
+}
+
+static int demux_c15_set(u64 id, void __user *uaddr)
+{
+ u32 val, newval;
+ u32 __user *uval = uaddr;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ switch (id & KVM_REG_ARM_DEMUX_ID_MASK) {
+ case KVM_REG_ARM_DEMUX_ID_CCSIDR:
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+ val = (id & KVM_REG_ARM_DEMUX_VAL_MASK)
+ >> KVM_REG_ARM_DEMUX_VAL_SHIFT;
+ if (!is_valid_cache(val))
+ return -ENOENT;
+
+ if (get_user(newval, uval))
+ return -EFAULT;
+
+ /* This is also invariant: you can't change it. */
+ if (newval != get_ccsidr(val))
+ return -EINVAL;
+ return 0;
+ default:
+ return -ENOENT;
+ }
+}
+
int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+ return demux_c15_get(reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return get_invariant_cp15(reg->id, uaddr);
@@ -566,6 +673,9 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
const struct coproc_reg *r;
void __user *uaddr = (void __user *)(long)reg->addr;
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
+ return demux_c15_set(reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return set_invariant_cp15(reg->id, uaddr);
@@ -574,6 +684,33 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return reg_from_user(&vcpu->arch.cp15[r->reg], uaddr, reg->id);
}
+static unsigned int num_demux_regs(void)
+{
+ unsigned int i, count = 0;
+
+ for (i = 0; i < CSSELR_MAX; i++)
+ if (is_valid_cache(i))
+ count++;
+
+ return count;
+}
+
+static int write_demux_regids(u64 __user *uindices)
+{
+ u64 val = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_DEMUX;
+ unsigned int i;
+
+ val |= KVM_REG_ARM_DEMUX_ID_CCSIDR;
+ for (i = 0; i < CSSELR_MAX; i++) {
+ if (!is_valid_cache(i))
+ continue;
+ if (put_user(val | i, uindices))
+ return -EFAULT;
+ uindices++;
+ }
+ return 0;
+}
+
static u64 cp15_to_index(const struct coproc_reg *reg)
{
u64 val = KVM_REG_ARM | (15 << KVM_REG_ARM_COPROC_SHIFT);
@@ -649,6 +786,7 @@ static int walk_cp15(struct kvm_vcpu *vcpu, u64 __user *uind)
unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
{
return ARRAY_SIZE(invariant_cp15)
+ + num_demux_regs()
+ walk_cp15(vcpu, (u64 __user *)NULL);
}
@@ -665,9 +803,11 @@ int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
}
err = walk_cp15(vcpu, uindices);
- if (err > 0)
- err = 0;
- return err;
+ if (err < 0)
+ return err;
+ uindices += err;
+
+ return write_demux_regids(uindices);
}
void kvm_coproc_table_init(void)
@@ -681,6 +821,23 @@ void kvm_coproc_table_init(void)
/* We abuse the reset function to overwrite the table itself. */
for (i = 0; i < ARRAY_SIZE(invariant_cp15); i++)
invariant_cp15[i].reset(NULL, &invariant_cp15[i]);
+
+ /*
+ * CLIDR format is awkward, so clean it up. See ARM B4.1.20:
+ *
+ * If software reads the Cache Type fields from Ctype1
+ * upwards, once it has seen a value of 0b000, no caches
+ * exist@further-out levels of the hierarchy. So, for
+ * example, if Ctype3 is the first Cache Type field with a
+ * value of 0b000, the values of Ctype4 to Ctype7 must be
+ * ignored.
+ */
+ asm volatile("mrc p15, 1, %0, c0, c0, 1" : "=r" (cache_levels));
+ for (i = 0; i < 7; i++)
+ if (((cache_levels >> (i*3)) & 7) == 0)
+ break;
+ /* Clear all higher bits. */
+ cache_levels &= (1 << (i*3))-1;
}
/**
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 12/14] KVM: ARM: VFP userspace interface
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (10 preceding siblings ...)
2012-10-22 6:50 ` [PATCH v3 11/14] KVM: ARM: Demux CCSIDR in the userspace API Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 13/14] KVM: ARM: Handle guest faults in KVM Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 14/14] KVM: ARM: Handle I/O aborts Christoffer Dall
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
From: Rusty Russell <rusty.russell@linaro.org>
We use space #18 for floating point regs.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
Documentation/virtual/kvm/api.txt | 6 +
arch/arm/include/uapi/asm/kvm.h | 12 ++
arch/arm/kvm/coproc.c | 178 +++++++++++++++++++++++++++++++++++++
3 files changed, 196 insertions(+)
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 6f87d61..764c5df 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -1807,6 +1807,12 @@ ARM 64-bit CP15 registers have the following id bit patterns:
ARM CCSIDR registers are demultiplexed by CSSELR value:
0x4002 0000 0011 00 <csselr:8>
+ARM 32-bit VFP control registers have the following id bit patterns:
+ 0x4002 0000 0012 1 <regno:12>
+
+ARM 64-bit FP registers have the following id bit patterns:
+ 0x4002 0000 0012 0 <regno:12>
+
4.69 KVM_GET_ONE_REG
Capability: KVM_CAP_ONE_REG
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index d79d064..fb41608 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -89,6 +89,18 @@ struct kvm_arch_memory_slot {
#define KVM_REG_ARM_DEMUX_VAL_MASK 0x00000000000000FF
#define KVM_REG_ARM_DEMUX_VAL_SHIFT 0
+/* VFP registers: we could overload CP10 like ARM does, but that's ugly. */
+#define KVM_REG_ARM_VFP (0x0012 << KVM_REG_ARM_COPROC_SHIFT)
+#define KVM_REG_ARM_VFP_MASK 0x000000000000FFFF
+#define KVM_REG_ARM_VFP_BASE_REG 0x0
+#define KVM_REG_ARM_VFP_FPSID 0x1000
+#define KVM_REG_ARM_VFP_FPSCR 0x1001
+#define KVM_REG_ARM_VFP_MVFR1 0x1006
+#define KVM_REG_ARM_VFP_MVFR0 0x1007
+#define KVM_REG_ARM_VFP_FPEXC 0x1008
+#define KVM_REG_ARM_VFP_FPINST 0x1009
+#define KVM_REG_ARM_VFP_FPINST2 0x100A
+
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 9ce5861..0b9b521 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -26,6 +26,8 @@
#include <asm/cacheflush.h>
#include <asm/cputype.h>
#include <trace/events/kvm.h>
+#include <asm/vfp.h>
+#include "../vfp/vfpinstr.h"
#include "trace.h"
#include "coproc.h"
@@ -652,6 +654,170 @@ static int demux_c15_set(u64 id, void __user *uaddr)
}
}
+#ifdef CONFIG_VFPv3
+static const int vfp_sysregs[] = { KVM_REG_ARM_VFP_FPEXC,
+ KVM_REG_ARM_VFP_FPSCR,
+ KVM_REG_ARM_VFP_FPINST,
+ KVM_REG_ARM_VFP_FPINST2,
+ KVM_REG_ARM_VFP_MVFR0,
+ KVM_REG_ARM_VFP_MVFR1,
+ KVM_REG_ARM_VFP_FPSID };
+
+static unsigned int num_fp_regs(void)
+{
+ if (((fmrx(MVFR0) & MVFR0_A_SIMD_MASK) >> MVFR0_A_SIMD_BIT) == 2)
+ return 32;
+ else
+ return 16;
+}
+
+static unsigned int num_vfp_regs(void)
+{
+ /* Normal FP regs + control regs. */
+ return num_fp_regs() + ARRAY_SIZE(vfp_sysregs);
+}
+
+static int copy_vfp_regids(u64 __user *uindices)
+{
+ unsigned int i;
+ const u64 u32reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP;
+ const u64 u64reg = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
+
+ for (i = 0; i < num_fp_regs(); i++) {
+ if (put_user((u64reg | KVM_REG_ARM_VFP_BASE_REG) + i,
+ uindices))
+ return -EFAULT;
+ uindices++;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(vfp_sysregs); i++) {
+ if (put_user(u32reg | vfp_sysregs[i], uindices))
+ return -EFAULT;
+ uindices++;
+ }
+
+ return num_vfp_regs();
+}
+
+static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)
+{
+ u32 vfpid = (id & KVM_REG_ARM_VFP_MASK);
+ u32 val;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ if (vfpid < num_fp_regs()) {
+ if (KVM_REG_SIZE(id) != 8)
+ return -ENOENT;
+ return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpregs[vfpid],
+ id);
+ }
+
+ /* FP control registers are all 32 bit. */
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+
+ switch (vfpid) {
+ case KVM_REG_ARM_VFP_FPEXC:
+ return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpexc, id);
+ case KVM_REG_ARM_VFP_FPSCR:
+ return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpscr, id);
+ case KVM_REG_ARM_VFP_FPINST:
+ return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst, id);
+ case KVM_REG_ARM_VFP_FPINST2:
+ return reg_to_user(uaddr, &vcpu->arch.vfp_guest.fpinst2, id);
+ case KVM_REG_ARM_VFP_MVFR0:
+ val = fmrx(MVFR0);
+ return reg_to_user(uaddr, &val, id);
+ case KVM_REG_ARM_VFP_MVFR1:
+ val = fmrx(MVFR1);
+ return reg_to_user(uaddr, &val, id);
+ case KVM_REG_ARM_VFP_FPSID:
+ val = fmrx(FPSID);
+ return reg_to_user(uaddr, &val, id);
+ default:
+ return -ENOENT;
+ }
+}
+
+static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)
+{
+ u32 vfpid = (id & KVM_REG_ARM_VFP_MASK);
+ u32 val;
+
+ /* Fail if we have unknown bits set. */
+ if (id & ~(KVM_REG_ARCH_MASK|KVM_REG_SIZE_MASK|KVM_REG_ARM_COPROC_MASK
+ | ((1 << KVM_REG_ARM_COPROC_SHIFT)-1)))
+ return -ENOENT;
+
+ if (vfpid < num_fp_regs()) {
+ if (KVM_REG_SIZE(id) != 8)
+ return -ENOENT;
+ return reg_from_user(&vcpu->arch.vfp_guest.fpregs[vfpid],
+ uaddr, id);
+ }
+
+ /* FP control registers are all 32 bit. */
+ if (KVM_REG_SIZE(id) != 4)
+ return -ENOENT;
+
+ switch (vfpid) {
+ case KVM_REG_ARM_VFP_FPEXC:
+ return reg_from_user(&vcpu->arch.vfp_guest.fpexc, uaddr, id);
+ case KVM_REG_ARM_VFP_FPSCR:
+ return reg_from_user(&vcpu->arch.vfp_guest.fpscr, uaddr, id);
+ case KVM_REG_ARM_VFP_FPINST:
+ return reg_from_user(&vcpu->arch.vfp_guest.fpinst, uaddr, id);
+ case KVM_REG_ARM_VFP_FPINST2:
+ return reg_from_user(&vcpu->arch.vfp_guest.fpinst2, uaddr, id);
+ /* These are invariant. */
+ case KVM_REG_ARM_VFP_MVFR0:
+ if (reg_from_user(&val, uaddr, id))
+ return -EFAULT;
+ if (val != fmrx(MVFR0))
+ return -EINVAL;
+ return 0;
+ case KVM_REG_ARM_VFP_MVFR1:
+ if (reg_from_user(&val, uaddr, id))
+ return -EFAULT;
+ if (val != fmrx(MVFR1))
+ return -EINVAL;
+ return 0;
+ case KVM_REG_ARM_VFP_FPSID:
+ if (reg_from_user(&val, uaddr, id))
+ return -EFAULT;
+ if (val != fmrx(FPSID))
+ return -EINVAL;
+ return 0;
+ default:
+ return -ENOENT;
+ }
+}
+#else /* !CONFIG_VFPv3 */
+static unsigned int num_vfp_regs(void)
+{
+ return 0;
+}
+
+static int copy_vfp_regids(u64 __user *uindices)
+{
+ return 0;
+}
+
+static int vfp_get_reg(const struct kvm_vcpu *vcpu, u64 id, void __user *uaddr)
+{
+ return -ENOENT;
+}
+
+static int vfp_set_reg(struct kvm_vcpu *vcpu, u64 id, const void __user *uaddr)
+{
+ return -ENOENT;
+}
+#endif /* !CONFIG_VFPv3 */
+
int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
{
const struct coproc_reg *r;
@@ -660,6 +826,9 @@ int kvm_arm_coproc_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
return demux_c15_get(reg->id, uaddr);
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_VFP)
+ return vfp_get_reg(vcpu, reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return get_invariant_cp15(reg->id, uaddr);
@@ -676,6 +845,9 @@ int kvm_arm_coproc_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_DEMUX)
return demux_c15_set(reg->id, uaddr);
+ if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_VFP)
+ return vfp_set_reg(vcpu, reg->id, uaddr);
+
r = index_to_coproc_reg(vcpu, reg->id);
if (!r)
return set_invariant_cp15(reg->id, uaddr);
@@ -787,6 +959,7 @@ unsigned long kvm_arm_num_coproc_regs(struct kvm_vcpu *vcpu)
{
return ARRAY_SIZE(invariant_cp15)
+ num_demux_regs()
+ + num_vfp_regs()
+ walk_cp15(vcpu, (u64 __user *)NULL);
}
@@ -807,6 +980,11 @@ int kvm_arm_copy_coproc_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
return err;
uindices += err;
+ err = copy_vfp_regids(uindices);
+ if (err < 0)
+ return err;
+ uindices += err;
+
return write_demux_regids(uindices);
}
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 13/14] KVM: ARM: Handle guest faults in KVM
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (11 preceding siblings ...)
2012-10-22 6:50 ` [PATCH v3 12/14] KVM: ARM: VFP userspace interface Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
2012-10-22 6:50 ` [PATCH v3 14/14] KVM: ARM: Handle I/O aborts Christoffer Dall
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
Handles the guest faults in KVM by mapping in corresponding user pages
in the 2nd stage page tables.
We invalidate the instruction cache by MVA whenever we map a page to the
guest (no, we cannot only do it when we have an iabt because the guest
may happily read/write a page before hitting the icache) if the hardware
uses VIPT or PIPT. In the latter case, we can invalidate only that
physical page. In the first case, all bets are off and we simply must
invalidate the whole affair. Not that VIVT icaches are tagged with
vmids, and we are out of the woods on that one. Alexander Graf was nice
enough to remind us of this massive pain.
There is also a subtle bug hidden somewhere, which we currently hide by
marking all pages dirty even when the pages are only mapped read-only. The
current hypothesis is that marking pages dirty may exercise the IO system and
data cache more and therefore we don't see stale data in the guest, but it's
purely guesswork. The bug is manifested by seemingly random kernel crashes in
guests when the host is under extreme memory pressure and swapping is enabled.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 9 ++
arch/arm/include/asm/kvm_asm.h | 2 +
arch/arm/kvm/mmu.c | 145 ++++++++++++++++++++++++++++++++++++++++
arch/arm/kvm/trace.h | 26 +++++++
4 files changed, 181 insertions(+), 1 deletion(-)
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index 6b8bb51..61d8a26 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -152,11 +152,20 @@
#define HSR_ISS (HSR_IL - 1)
#define HSR_ISV_SHIFT (24)
#define HSR_ISV (1U << HSR_ISV_SHIFT)
+#define HSR_FSC (0x3f)
+#define HSR_FSC_TYPE (0x3c)
+#define HSR_WNR (1 << 6)
#define HSR_CV_SHIFT (24)
#define HSR_CV (1U << HSR_CV_SHIFT)
#define HSR_COND_SHIFT (20)
#define HSR_COND (0xfU << HSR_COND_SHIFT)
+#define FSC_FAULT (0x04)
+#define FSC_PERM (0x0c)
+
+/* Hyp Prefetch Fault Address Register (HPFAR/HDFAR) */
+#define HPFAR_MASK (~0xf)
+
#define HSR_EC_UNKNOWN (0x00)
#define HSR_EC_WFI (0x01)
#define HSR_EC_CP15_32 (0x03)
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 47a0e57..6fccdb3 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -71,6 +71,8 @@ extern char __kvm_hyp_vector[];
extern char __kvm_hyp_code_start[];
extern char __kvm_hyp_code_end[];
+extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
+
extern void __kvm_flush_vm_context(void);
extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index f45be86..9e2230d 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -21,9 +21,11 @@
#include <linux/io.h>
#include <asm/idmap.h>
#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_asm.h>
+#include <asm/kvm_emulate.h>
#include <asm/mach/map.h>
#include <trace/events/kvm.h>
@@ -503,9 +505,150 @@ out:
return ret;
}
+static void coherent_icache_guest_page(struct kvm *kvm, gfn_t gfn)
+{
+ /*
+ * If we are going to insert an instruction page and the icache is
+ * either VIPT or PIPT, there is a potential problem where the host
+ * (or another VM) may have used this page at the same virtual address
+ * as this guest, and we read incorrect data from the icache. If
+ * we're using a PIPT cache, we can invalidate just that page, but if
+ * we are using a VIPT cache we need to invalidate the entire icache -
+ * damn shame - as written in the ARM ARM (DDI 0406C - Page B3-1384)
+ */
+ if (icache_is_pipt()) {
+ unsigned long hva = gfn_to_hva(kvm, gfn);
+ __cpuc_coherent_user_range(hva, hva + PAGE_SIZE);
+ } else if (!icache_is_vivt_asid_tagged()) {
+ /* any kind of VIPT cache */
+ __flush_icache_all();
+ }
+}
+
+static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
+ gfn_t gfn, struct kvm_memory_slot *memslot,
+ bool is_iabt, unsigned long fault_status)
+{
+ pte_t new_pte;
+ pfn_t pfn;
+ int ret;
+ bool write_fault, writable;
+ unsigned long mmu_seq;
+ struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
+
+ if (is_iabt)
+ write_fault = false;
+ else if ((vcpu->arch.hsr & HSR_ISV) && !(vcpu->arch.hsr & HSR_WNR))
+ write_fault = false;
+ else
+ write_fault = true;
+
+ if (fault_status == FSC_PERM && !write_fault) {
+ kvm_err("Unexpected L2 read permission error\n");
+ return -EFAULT;
+ }
+
+ /* We need minimum second+third level pages */
+ ret = mmu_topup_memory_cache(memcache, 2, KVM_NR_MEM_OBJS);
+ if (ret)
+ return ret;
+
+ mmu_seq = vcpu->kvm->mmu_notifier_seq;
+ smp_rmb();
+
+ pfn = gfn_to_pfn_prot(vcpu->kvm, gfn, write_fault, &writable);
+ if (is_error_pfn(pfn))
+ return -EFAULT;
+
+ new_pte = pfn_pte(pfn, PAGE_S2);
+ coherent_icache_guest_page(vcpu->kvm, gfn);
+
+ spin_lock(&vcpu->kvm->mmu_lock);
+ if (mmu_notifier_retry(vcpu, mmu_seq))
+ goto out_unlock;
+ if (writable) {
+ pte_val(new_pte) |= L_PTE_S2_RDWR;
+ kvm_set_pfn_dirty(pfn);
+ }
+ stage2_set_pte(vcpu->kvm, memcache, fault_ipa, &new_pte, false);
+
+out_unlock:
+ spin_unlock(&vcpu->kvm->mmu_lock);
+ /*
+ * XXX TODO FIXME:
+- * This is _really_ *weird* !!!
+- * We should be calling the _clean version, because we set the pfn dirty
+ * if we map the page writable, but this causes memory failures in
+ * guests under heavy memory pressure on the host and heavy swapping.
+ */
+ kvm_release_pfn_dirty(pfn);
+ return 0;
+}
+
+/**
+ * kvm_handle_guest_abort - handles all 2nd stage aborts
+ * @vcpu: the VCPU pointer
+ * @run: the kvm_run structure
+ *
+ * Any abort that gets to the host is almost guaranteed to be caused by a
+ * missing second stage translation table entry, which can mean that either the
+ * guest simply needs more memory and we must allocate an appropriate page or it
+ * can mean that the guest tried to access I/O memory, which is emulated by user
+ * space. The distinction is based on the IPA causing the fault and whether this
+ * memory region has been registered as standard RAM by user space.
+ */
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
- return -EINVAL;
+ unsigned long hsr_ec;
+ unsigned long fault_status;
+ phys_addr_t fault_ipa;
+ struct kvm_memory_slot *memslot = NULL;
+ bool is_iabt;
+ gfn_t gfn;
+ int ret;
+
+ hsr_ec = vcpu->arch.hsr >> HSR_EC_SHIFT;
+ is_iabt = (hsr_ec == HSR_EC_IABT);
+ fault_ipa = ((phys_addr_t)vcpu->arch.hpfar & HPFAR_MASK) << 8;
+
+ trace_kvm_guest_fault(*vcpu_pc(vcpu), vcpu->arch.hsr,
+ vcpu->arch.hxfar, fault_ipa);
+
+ /* Check the stage-2 fault is trans. fault or write fault */
+ fault_status = (vcpu->arch.hsr & HSR_FSC_TYPE);
+ if (fault_status != FSC_FAULT && fault_status != FSC_PERM) {
+ kvm_err("Unsupported fault status: EC=%#lx DFCS=%#lx\n",
+ hsr_ec, fault_status);
+ return -EFAULT;
+ }
+
+ gfn = fault_ipa >> PAGE_SHIFT;
+ if (!kvm_is_visible_gfn(vcpu->kvm, gfn)) {
+ if (is_iabt) {
+ /* Prefetch Abort on I/O address */
+ kvm_inject_pabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ }
+
+ if (fault_status != FSC_FAULT) {
+ kvm_err("Unsupported fault status on io memory: %#lx\n",
+ fault_status);
+ return -EFAULT;
+ }
+
+ kvm_pr_unimpl("I/O address abort...");
+ return 0;
+ }
+
+ memslot = gfn_to_memslot(vcpu->kvm, gfn);
+ if (!memslot->user_alloc) {
+ kvm_err("non user-alloc memslots not supported\n");
+ return -EINVAL;
+ }
+
+ ret = user_mem_abort(vcpu, fault_ipa, gfn, memslot,
+ is_iabt, fault_status);
+ return ret ? ret : 1;
}
static void handle_hva_to_gpa(struct kvm *kvm,
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index c86a513..e2a9d2e 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -39,6 +39,32 @@ TRACE_EVENT(kvm_exit,
TP_printk("PC: 0x%08lx", __entry->vcpu_pc)
);
+TRACE_EVENT(kvm_guest_fault,
+ TP_PROTO(unsigned long vcpu_pc, unsigned long hsr,
+ unsigned long hxfar,
+ unsigned long ipa),
+ TP_ARGS(vcpu_pc, hsr, hxfar, ipa),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( unsigned long, hsr )
+ __field( unsigned long, hxfar )
+ __field( unsigned long, ipa )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->hsr = hsr;
+ __entry->hxfar = hxfar;
+ __entry->ipa = ipa;
+ ),
+
+ TP_printk("guest fault at PC %#08lx (hxfar %#08lx, "
+ "ipa %#08lx, hsr %#08lx",
+ __entry->vcpu_pc, __entry->hxfar,
+ __entry->hsr, __entry->ipa)
+);
+
TRACE_EVENT(kvm_irq_line,
TP_PROTO(unsigned int type, int vcpu_idx, int irq_num, int level),
TP_ARGS(type, vcpu_idx, irq_num, level),
^ permalink raw reply related [flat|nested] 17+ messages in thread* [PATCH v3 14/14] KVM: ARM: Handle I/O aborts
2012-10-22 6:48 [PATCH v3 00/14] KVM/ARM Implementation Christoffer Dall
` (12 preceding siblings ...)
2012-10-22 6:50 ` [PATCH v3 13/14] KVM: ARM: Handle guest faults in KVM Christoffer Dall
@ 2012-10-22 6:50 ` Christoffer Dall
13 siblings, 0 replies; 17+ messages in thread
From: Christoffer Dall @ 2012-10-22 6:50 UTC (permalink / raw)
To: linux-arm-kernel
When the guest accesses I/O memory this will create data abort
exceptions and they are handled by decoding the HSR information
(physical address, read/write, length, register) and forwarding reads
and writes to QEMU which performs the device emulation.
Certain classes of load/store operations do not support the syndrome
information provided in the HSR and we therefore must be able to fetch
the offending instruction from guest memory and decode it manually.
We only support instruction decoding for valid reasonable MMIO operations
where trapping them do not provide sufficient information in the HSR (no
16-bit Thumb instructions provide register writeback that we care about).
The following instruciton types are NOT supported for MMIO operations
despite the HSR not containing decode info:
- any Load/Store multiple
- any load/store exclusive
- any load/store dual
- anything with the PC as the dest register
This requires changing the general flow somewhat since new calls to run
the VCPU must check if there's a pending MMIO load and perform the write
after userspace has made the data available.
Rusty Russell fixed a horrible race pointed out by Ben Herrenschmidt:
(1) Guest complicated mmio instruction traps.
(2) The hardware doesn't tell us enough, so we need to read the actual
instruction which was being exectuted.
(3) KVM maps the instruction virtual address to a physical address.
(4) The guest (SMP) swaps out that page, and fills it with something else.
(5) We read the physical address, but now that's the wrong thing.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Rusty Russell <rusty.russell@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 3
arch/arm/include/asm/kvm_asm.h | 2
arch/arm/include/asm/kvm_emulate.h | 8
arch/arm/include/asm/kvm_host.h | 3
arch/arm/include/asm/kvm_mmio.h | 51 +++
arch/arm/kvm/Makefile | 2
arch/arm/kvm/arm.c | 14 +
arch/arm/kvm/emulate.c | 581 ++++++++++++++++++++++++++++++++++++
arch/arm/kvm/interrupts.S | 38 ++
arch/arm/kvm/mmio.c | 152 +++++++++
arch/arm/kvm/mmu.c | 7
arch/arm/kvm/trace.h | 21 +
12 files changed, 878 insertions(+), 4 deletions(-)
create mode 100644 arch/arm/include/asm/kvm_mmio.h
create mode 100644 arch/arm/kvm/mmio.c
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index 61d8a26..4f1bb01 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -152,8 +152,11 @@
#define HSR_ISS (HSR_IL - 1)
#define HSR_ISV_SHIFT (24)
#define HSR_ISV (1U << HSR_ISV_SHIFT)
+#define HSR_SRT_SHIFT (16)
+#define HSR_SRT_MASK (0xf << HSR_SRT_SHIFT)
#define HSR_FSC (0x3f)
#define HSR_FSC_TYPE (0x3c)
+#define HSR_SSE (1 << 21)
#define HSR_WNR (1 << 6)
#define HSR_CV_SHIFT (24)
#define HSR_CV (1U << HSR_CV_SHIFT)
diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h
index 6fccdb3..99c0faf 100644
--- a/arch/arm/include/asm/kvm_asm.h
+++ b/arch/arm/include/asm/kvm_asm.h
@@ -77,6 +77,8 @@ extern void __kvm_flush_vm_context(void);
extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
+
+extern u64 __kvm_va_to_pa(struct kvm_vcpu *vcpu, u32 va, bool priv);
#endif
#endif /* __ARM_KVM_ASM_H__ */
diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h
index ac48156..b94863a 100644
--- a/arch/arm/include/asm/kvm_emulate.h
+++ b/arch/arm/include/asm/kvm_emulate.h
@@ -21,11 +21,14 @@
#include <linux/kvm_host.h>
#include <asm/kvm_asm.h>
+#include <asm/kvm_mmio.h>
u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num);
u32 *vcpu_spsr(struct kvm_vcpu *vcpu);
int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int kvm_emulate_mmio_ls(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
+ struct kvm_exit_mmio *mmio);
void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr);
void kvm_inject_undefined(struct kvm_vcpu *vcpu);
void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr);
@@ -53,4 +56,9 @@ static inline bool vcpu_mode_priv(struct kvm_vcpu *vcpu)
return cpsr_mode > USR_MODE;;
}
+static inline bool kvm_vcpu_reg_is_pc(struct kvm_vcpu *vcpu, int reg)
+{
+ return reg == 15;
+}
+
#endif /* __ARM_KVM_EMULATE_H__ */
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 606e21a..2eddd96 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -99,6 +99,9 @@ struct kvm_vcpu_arch {
int last_pcpu;
cpumask_t require_dcache_flush;
+ /* Don't run the guest: see copy_current_insn() */
+ bool pause;
+
/* IO related fields */
struct {
bool sign_extend; /* for byte/halfword loads */
diff --git a/arch/arm/include/asm/kvm_mmio.h b/arch/arm/include/asm/kvm_mmio.h
new file mode 100644
index 0000000..31ab9f5
--- /dev/null
+++ b/arch/arm/include/asm/kvm_mmio.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __ARM_KVM_MMIO_H__
+#define __ARM_KVM_MMIO_H__
+
+#include <linux/kvm_host.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+
+/*
+ * The in-kernel MMIO emulation code wants to use a copy of run->mmio,
+ * which is an anonymous type. Use our own type instead.
+ */
+struct kvm_exit_mmio {
+ phys_addr_t phys_addr;
+ u8 data[8];
+ u32 len;
+ bool is_write;
+};
+
+static inline void kvm_prepare_mmio(struct kvm_run *run,
+ struct kvm_exit_mmio *mmio)
+{
+ run->mmio.phys_addr = mmio->phys_addr;
+ run->mmio.len = mmio->len;
+ run->mmio.is_write = mmio->is_write;
+ memcpy(run->mmio.data, mmio->data, mmio->len);
+ run->exit_reason = KVM_EXIT_MMIO;
+}
+
+int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run);
+int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ phys_addr_t fault_ipa, struct kvm_memory_slot *memslot);
+
+#endif /* __ARM_KVM_MMIO_H__ */
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index ea5b282..574c67c 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -19,4 +19,4 @@ obj-$(CONFIG_KVM_ARM_HOST) += init.o interrupts.o
obj-$(CONFIG_KVM_ARM_HOST) += $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o)
obj-$(CONFIG_KVM_ARM_HOST) += arm.o guest.o mmu.o emulate.o reset.o
-obj-$(CONFIG_KVM_ARM_HOST) += coproc.o coproc_a15.o
+obj-$(CONFIG_KVM_ARM_HOST) += coproc.o coproc_a15.o mmio.o
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index c547797..acdfa63 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -580,6 +580,12 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
if (unlikely(vcpu->arch.target < 0))
return -ENOEXEC;
+ if (run->exit_reason == KVM_EXIT_MMIO) {
+ ret = kvm_handle_mmio_return(vcpu, vcpu->run);
+ if (ret)
+ return ret;
+ }
+
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
@@ -615,7 +621,13 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
kvm_guest_enter();
vcpu->mode = IN_GUEST_MODE;
- ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
+ smp_mb(); /* set mode before reading vcpu->arch.pause */
+ if (unlikely(vcpu->arch.pause)) {
+ /* This means ignore, try again. */
+ ret = ARM_EXCEPTION_IRQ;
+ } else {
+ ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
+ }
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->arch.last_pcpu = smp_processor_id();
diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
index 546cdaf..30124cb 100644
--- a/arch/arm/kvm/emulate.c
+++ b/arch/arm/kvm/emulate.c
@@ -172,6 +172,587 @@ int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
return 1;
}
+static u64 kvm_va_to_pa(struct kvm_vcpu *vcpu, u32 va, bool priv)
+{
+ return kvm_call_hyp(__kvm_va_to_pa, vcpu, va, priv);
+}
+
+/**
+ * copy_from_guest_va - copy memory from guest (very slow!)
+ * @vcpu: vcpu pointer
+ * @dest: memory to copy into
+ * @gva: virtual address in guest to copy from
+ * @len: length to copy
+ * @priv: use guest PL1 (ie. kernel) mappings
+ * otherwise use guest PL0 mappings.
+ *
+ * Returns true on success, false on failure (unlikely, but retry).
+ */
+static bool copy_from_guest_va(struct kvm_vcpu *vcpu,
+ void *dest, unsigned long gva, size_t len,
+ bool priv)
+{
+ u64 par;
+ phys_addr_t pc_ipa;
+ int err;
+
+ BUG_ON((gva & PAGE_MASK) != ((gva + len) & PAGE_MASK));
+ par = kvm_va_to_pa(vcpu, gva & PAGE_MASK, priv);
+ if (par & 1) {
+ kvm_err("IO abort from invalid instruction address"
+ " %#lx!\n", gva);
+ return false;
+ }
+
+ BUG_ON(!(par & (1U << 11)));
+ pc_ipa = par & PAGE_MASK & ((1ULL << 32) - 1);
+ pc_ipa += gva & ~PAGE_MASK;
+
+
+ err = kvm_read_guest(vcpu->kvm, pc_ipa, dest, len);
+ if (unlikely(err))
+ return false;
+
+ return true;
+}
+
+/* Just ensure we're not running the guest. */
+static void do_nothing(void *info)
+{
+}
+
+/*
+ * We have to be very careful copying memory from a running (ie. SMP) guest.
+ * Another CPU may remap the page (eg. swap out a userspace text page) as we
+ * read the instruction. Unlike normal hardware operation, to emulate an
+ * instruction we map the virtual to physical address then read that memory
+ * as separate steps, thus not atomic.
+ *
+ * Fortunately this is so rare (we don't usually need the instruction), we
+ * can go very slowly and noone will mind.
+ */
+static bool copy_current_insn(struct kvm_vcpu *vcpu, unsigned long *instr)
+{
+ int i;
+ bool ret;
+ struct kvm_vcpu *v;
+ bool is_thumb;
+ size_t instr_len;
+
+ /* Don't cross with IPIs in kvm_main.c */
+ spin_lock(&vcpu->kvm->mmu_lock);
+
+ /* Tell them all to pause, so no more will enter guest. */
+ kvm_for_each_vcpu(i, v, vcpu->kvm)
+ v->arch.pause = true;
+
+ /* Set ->pause before we read ->mode */
+ smp_mb();
+
+ /* Kick out any which are still running. */
+ kvm_for_each_vcpu(i, v, vcpu->kvm) {
+ /* Guest could exit now, making cpu wrong. That's OK. */
+ if (kvm_vcpu_exiting_guest_mode(v) == IN_GUEST_MODE)
+ smp_call_function_single(v->cpu, do_nothing, NULL, 1);
+ }
+
+
+ is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_T_BIT);
+ instr_len = (is_thumb) ? 2 : 4;
+
+ BUG_ON(!is_thumb && *vcpu_pc(vcpu) & 0x3);
+
+ /* Now guest isn't running, we can va->pa map and copy atomically. */
+ ret = copy_from_guest_va(vcpu, instr, *vcpu_pc(vcpu), instr_len,
+ vcpu_mode_priv(vcpu));
+ if (!ret)
+ goto out;
+
+ /* A 32-bit thumb2 instruction can actually go over a page boundary! */
+ if (is_thumb && is_wide_instruction(*instr)) {
+ *instr = *instr << 16;
+ ret = copy_from_guest_va(vcpu, instr, *vcpu_pc(vcpu) + 2, 2,
+ vcpu_mode_priv(vcpu));
+ }
+
+out:
+ /* Release them all. */
+ kvm_for_each_vcpu(i, v, vcpu->kvm)
+ v->arch.pause = false;
+
+ spin_unlock(&vcpu->kvm->mmu_lock);
+
+ return ret;
+}
+
+/******************************************************************************
+ * Load-Store instruction emulation
+ *****************************************************************************/
+
+struct arm_instr {
+ /* Instruction decoding */
+ u32 opc;
+ u32 opc_mask;
+
+ /* Decoding for the register write back */
+ bool register_form;
+ u32 imm;
+ u8 Rm;
+ u8 type;
+ u8 shift_n;
+
+ /* Common decoding */
+ u8 len;
+ bool sign_extend;
+ bool w;
+
+ bool (*decode)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, struct arm_instr *ai);
+};
+
+enum SRType {
+ SRType_LSL,
+ SRType_LSR,
+ SRType_ASR,
+ SRType_ROR,
+ SRType_RRX
+};
+
+/* Modelled after DecodeImmShift() in the ARM ARM */
+enum SRType decode_imm_shift(u8 type, u8 imm5, u8 *amount)
+{
+ switch (type) {
+ case 0x0:
+ *amount = imm5;
+ return SRType_LSL;
+ case 0x1:
+ *amount = (imm5 == 0) ? 32 : imm5;
+ return SRType_LSR;
+ case 0x2:
+ *amount = (imm5 == 0) ? 32 : imm5;
+ return SRType_ASR;
+ case 0x3:
+ if (imm5 == 0) {
+ *amount = 1;
+ return SRType_RRX;
+ } else {
+ *amount = imm5;
+ return SRType_ROR;
+ }
+ }
+
+ return SRType_LSL;
+}
+
+/* Modelled after Shift() in the ARM ARM */
+u32 shift(u32 value, u8 N, enum SRType type, u8 amount, bool carry_in)
+{
+ u32 mask = (1 << N) - 1;
+ s32 svalue = (s32)value;
+
+ BUG_ON(N > 32);
+ BUG_ON(type == SRType_RRX && amount != 1);
+ BUG_ON(amount > N);
+
+ if (amount == 0)
+ return value;
+
+ switch (type) {
+ case SRType_LSL:
+ value <<= amount;
+ break;
+ case SRType_LSR:
+ value >>= amount;
+ break;
+ case SRType_ASR:
+ if (value & (1 << (N - 1)))
+ svalue |= ((-1UL) << N);
+ value = svalue >> amount;
+ break;
+ case SRType_ROR:
+ value = (value >> amount) | (value << (N - amount));
+ break;
+ case SRType_RRX: {
+ u32 C = (carry_in) ? 1 : 0;
+ value = (value >> 1) | (C << (N - 1));
+ break;
+ }
+ }
+
+ return value & mask;
+}
+
+static bool decode_arm_wb(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, const struct arm_instr *ai)
+{
+ u8 Rt = (instr >> 12) & 0xf;
+ u8 Rn = (instr >> 16) & 0xf;
+ u8 W = (instr >> 21) & 1;
+ u8 U = (instr >> 23) & 1;
+ u8 P = (instr >> 24) & 1;
+ u32 base_addr = *vcpu_reg(vcpu, Rn);
+ u32 offset_addr, offset;
+
+ /*
+ * Technically this is allowed in certain circumstances,
+ * but we don't support it.
+ */
+ if (Rt == 15 || Rn == 15)
+ return false;
+
+ if (P && !W) {
+ kvm_err("Decoding operation with valid ISV?\n");
+ return false;
+ }
+
+ vcpu->arch.mmio.rd = Rt;
+
+ if (ai->register_form) {
+ /* Register operation */
+ enum SRType s_type;
+ u8 shift_n;
+ bool c_bit = *vcpu_cpsr(vcpu) & PSR_C_BIT;
+ u32 s_reg = *vcpu_reg(vcpu, ai->Rm);
+
+ s_type = decode_imm_shift(ai->type, ai->shift_n, &shift_n);
+ offset = shift(s_reg, 5, s_type, shift_n, c_bit);
+ } else {
+ /* Immediate operation */
+ offset = ai->imm;
+ }
+
+ /* Handle Writeback */
+ if (U)
+ offset_addr = base_addr + offset;
+ else
+ offset_addr = base_addr - offset;
+ *vcpu_reg(vcpu, Rn) = offset_addr;
+ return true;
+}
+
+static bool decode_arm_ls(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, struct arm_instr *ai)
+{
+ u8 A = (instr >> 25) & 1;
+
+ mmio->is_write = ai->w;
+ mmio->len = ai->len;
+ vcpu->arch.mmio.sign_extend = false;
+
+ ai->register_form = A;
+ ai->imm = instr & 0xfff;
+ ai->Rm = instr & 0xf;
+ ai->type = (instr >> 5) & 0x3;
+ ai->shift_n = (instr >> 7) & 0x1f;
+
+ return decode_arm_wb(vcpu, mmio, instr, ai);
+}
+
+static bool decode_arm_extra(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, struct arm_instr *ai)
+{
+ mmio->is_write = ai->w;
+ mmio->len = ai->len;
+ vcpu->arch.mmio.sign_extend = ai->sign_extend;
+
+ ai->register_form = !((instr >> 22) & 1);
+ ai->imm = ((instr >> 4) & 0xf0) | (instr & 0xf);
+ ai->Rm = instr & 0xf;
+ ai->type = 0; /* SRType_LSL */
+ ai->shift_n = 0;
+
+ return decode_arm_wb(vcpu, mmio, instr, ai);
+}
+
+/*
+ * The encodings in this table assumes that a fault was generated where the
+ * ISV field in the HSR was clear, and the decoding information was invalid,
+ * which means that a register write-back occurred, the PC was used as the
+ * destination or a load/store multiple operation was used. Since the latter
+ * two cases are crazy for MMIO on the guest side, we simply inject a fault
+ * when this happens and support the common case.
+ *
+ * We treat unpriviledged loads and stores of words and bytes like all other
+ * loads and stores as their encodings mandate the W bit set and the P bit
+ * clear.
+ */
+static const struct arm_instr arm_instr[] = {
+ /**************** Load/Store Word and Byte **********************/
+ /* Store word with writeback */
+ { .opc = 0x04000000, .opc_mask = 0x0c500000, .len = 4, .w = true,
+ .sign_extend = false, .decode = decode_arm_ls },
+ /* Store byte with writeback */
+ { .opc = 0x04400000, .opc_mask = 0x0c500000, .len = 1, .w = true,
+ .sign_extend = false, .decode = decode_arm_ls },
+ /* Load word with writeback */
+ { .opc = 0x04100000, .opc_mask = 0x0c500000, .len = 4, .w = false,
+ .sign_extend = false, .decode = decode_arm_ls },
+ /* Load byte with writeback */
+ { .opc = 0x04500000, .opc_mask = 0x0c500000, .len = 1, .w = false,
+ .sign_extend = false, .decode = decode_arm_ls },
+
+ /*************** Extra load/store instructions ******************/
+
+ /* Store halfword with writeback */
+ { .opc = 0x000000b0, .opc_mask = 0x0c1000f0, .len = 2, .w = true,
+ .sign_extend = false, .decode = decode_arm_extra },
+ /* Load halfword with writeback */
+ { .opc = 0x001000b0, .opc_mask = 0x0c1000f0, .len = 2, .w = false,
+ .sign_extend = false, .decode = decode_arm_extra },
+
+ /* Load dual with writeback */
+ { .opc = 0x000000d0, .opc_mask = 0x0c1000f0, .len = 8, .w = false,
+ .sign_extend = false, .decode = decode_arm_extra },
+ /* Load signed byte with writeback */
+ { .opc = 0x001000d0, .opc_mask = 0x0c1000f0, .len = 1, .w = false,
+ .sign_extend = true, .decode = decode_arm_extra },
+
+ /* Store dual with writeback */
+ { .opc = 0x000000f0, .opc_mask = 0x0c1000f0, .len = 8, .w = true,
+ .sign_extend = false, .decode = decode_arm_extra },
+ /* Load signed halfword with writeback */
+ { .opc = 0x001000f0, .opc_mask = 0x0c1000f0, .len = 2, .w = false,
+ .sign_extend = true, .decode = decode_arm_extra },
+
+ /* Store halfword unprivileged */
+ { .opc = 0x002000b0, .opc_mask = 0x0f3000f0, .len = 2, .w = true,
+ .sign_extend = false, .decode = decode_arm_extra },
+ /* Load halfword unprivileged */
+ { .opc = 0x003000b0, .opc_mask = 0x0f3000f0, .len = 2, .w = false,
+ .sign_extend = false, .decode = decode_arm_extra },
+ /* Load signed byte unprivileged */
+ { .opc = 0x003000d0, .opc_mask = 0x0f3000f0, .len = 1, .w = false,
+ .sign_extend = true , .decode = decode_arm_extra },
+ /* Load signed halfword unprivileged */
+ { .opc = 0x003000d0, .opc_mask = 0x0f3000f0, .len = 2, .w = false,
+ .sign_extend = true , .decode = decode_arm_extra },
+};
+
+static bool kvm_decode_arm_ls(struct kvm_vcpu *vcpu, unsigned long instr,
+ struct kvm_exit_mmio *mmio)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(arm_instr); i++) {
+ const struct arm_instr *ai = &arm_instr[i];
+ if ((instr & ai->opc_mask) == ai->opc) {
+ struct arm_instr ai_copy = *ai;
+ return ai->decode(vcpu, mmio, instr, &ai_copy);
+ }
+ }
+ return false;
+}
+
+struct thumb_instr {
+ bool is32;
+
+ union {
+ struct {
+ u8 opcode;
+ u8 mask;
+ } t16;
+
+ struct {
+ u8 op1;
+ u8 op2;
+ u8 op2_mask;
+ } t32;
+ };
+
+ bool (*decode)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, const struct thumb_instr *ti);
+};
+
+static bool decode_thumb_wb(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr)
+{
+ bool P = (instr >> 10) & 1;
+ bool U = (instr >> 9) & 1;
+ u8 imm8 = instr & 0xff;
+ u32 offset_addr = vcpu->arch.hxfar;
+ u8 Rn = (instr >> 16) & 0xf;
+
+ vcpu->arch.mmio.rd = (instr >> 12) & 0xf;
+
+ if (kvm_vcpu_reg_is_pc(vcpu, Rn))
+ return false;
+
+ /* Handle Writeback */
+ if (!P && U)
+ *vcpu_reg(vcpu, Rn) = offset_addr + imm8;
+ else if (!P && !U)
+ *vcpu_reg(vcpu, Rn) = offset_addr - imm8;
+ return true;
+}
+
+static bool decode_thumb_str(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, const struct thumb_instr *ti)
+{
+ u8 op1 = (instr >> (16 + 5)) & 0x7;
+ u8 op2 = (instr >> 6) & 0x3f;
+
+ mmio->is_write = true;
+ vcpu->arch.mmio.sign_extend = false;
+
+ switch (op1) {
+ case 0x0: mmio->len = 1; break;
+ case 0x1: mmio->len = 2; break;
+ case 0x2: mmio->len = 4; break;
+ default:
+ return false; /* Only register write-back versions! */
+ }
+
+ if ((op2 & 0x24) == 0x24) {
+ /* STRB (immediate, thumb, W=1) */
+ return decode_thumb_wb(vcpu, mmio, instr);
+ }
+
+ return false;
+}
+
+static bool decode_thumb_ldr(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
+ unsigned long instr, const struct thumb_instr *ti)
+{
+ u8 op1 = (instr >> (16 + 7)) & 0x3;
+ u8 op2 = (instr >> 6) & 0x3f;
+
+ mmio->is_write = false;
+
+ switch (ti->t32.op2 & 0x7) {
+ case 0x1: mmio->len = 1; break;
+ case 0x3: mmio->len = 2; break;
+ case 0x5: mmio->len = 4; break;
+ }
+
+ if (op1 == 0x0)
+ vcpu->arch.mmio.sign_extend = false;
+ else if (op1 == 0x2 && (ti->t32.op2 & 0x7) != 0x5)
+ vcpu->arch.mmio.sign_extend = true;
+ else
+ return false; /* Only register write-back versions! */
+
+ if ((op2 & 0x24) == 0x24) {
+ /* LDR{S}X (immediate, thumb, W=1) */
+ return decode_thumb_wb(vcpu, mmio, instr);
+ }
+
+ return false;
+}
+
+/*
+ * We only support instruction decoding for valid reasonable MMIO operations
+ * where trapping them do not provide sufficient information in the HSR (no
+ * 16-bit Thumb instructions provide register writeback that we care about).
+ *
+ * The following instruciton types are NOT supported for MMIO operations
+ * despite the HSR not containing decode info:
+ * - any Load/Store multiple
+ * - any load/store exclusive
+ * - any load/store dual
+ * - anything with the PC as the dest register
+ */
+static const struct thumb_instr thumb_instr[] = {
+ /**************** 32-bit Thumb instructions **********************/
+ /* Store single data item: Op1 == 11, Op2 == 000xxx0 */
+ { .is32 = true, .t32 = { 3, 0x00, 0x71}, decode_thumb_str },
+ /* Load byte: Op1 == 11, Op2 == 00xx001 */
+ { .is32 = true, .t32 = { 3, 0x01, 0x67}, decode_thumb_ldr },
+ /* Load halfword: Op1 == 11, Op2 == 00xx011 */
+ { .is32 = true, .t32 = { 3, 0x03, 0x67}, decode_thumb_ldr },
+ /* Load word: Op1 == 11, Op2 == 00xx101 */
+ { .is32 = true, .t32 = { 3, 0x05, 0x67}, decode_thumb_ldr },
+};
+
+
+
+static bool kvm_decode_thumb_ls(struct kvm_vcpu *vcpu, unsigned long instr,
+ struct kvm_exit_mmio *mmio)
+{
+ bool is32 = is_wide_instruction(instr);
+ bool is16 = !is32;
+ struct thumb_instr tinstr; /* re-use to pass on already decoded info */
+ int i;
+
+ if (is16) {
+ tinstr.t16.opcode = (instr >> 10) & 0x3f;
+ } else {
+ tinstr.t32.op1 = (instr >> (16 + 11)) & 0x3;
+ tinstr.t32.op2 = (instr >> (16 + 4)) & 0x7f;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(thumb_instr); i++) {
+ const struct thumb_instr *ti = &thumb_instr[i];
+ if (ti->is32 != is32)
+ continue;
+
+ if (is16) {
+ if ((tinstr.t16.opcode & ti->t16.mask) != ti->t16.opcode)
+ continue;
+ } else {
+ if (ti->t32.op1 != tinstr.t32.op1)
+ continue;
+ if ((ti->t32.op2_mask & tinstr.t32.op2) != ti->t32.op2)
+ continue;
+ }
+
+ return ti->decode(vcpu, mmio, instr, &tinstr);
+ }
+
+ return false;
+}
+
+/**
+ * kvm_emulate_mmio_ls - emulates load/store instructions made to I/O memory
+ * @vcpu: The vcpu pointer
+ * @fault_ipa: The IPA that caused the 2nd stage fault
+ * @mmio: Pointer to struct to hold decode information
+ *
+ * Some load/store instructions cannot be emulated using the information
+ * presented in the HSR, for instance, register write-back instructions are not
+ * supported. We therefore need to fetch the instruction, decode it, and then
+ * emulate its behavior.
+ *
+ * Handles emulation of load/store instructions which cannot be emulated through
+ * information found in the HSR on faults. It is necessary in this case to
+ * simply decode the offending instruction in software and determine the
+ * required operands.
+ */
+int kvm_emulate_mmio_ls(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
+ struct kvm_exit_mmio *mmio)
+{
+ bool is_thumb;
+ unsigned long instr = 0;
+
+ trace_kvm_mmio_emulate(*vcpu_pc(vcpu), instr, *vcpu_cpsr(vcpu));
+
+ /* If it fails (SMP race?), we reenter guest for it to retry. */
+ if (!copy_current_insn(vcpu, &instr))
+ return 1;
+
+ mmio->phys_addr = fault_ipa;
+ is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_T_BIT);
+ if (!is_thumb && !kvm_decode_arm_ls(vcpu, instr, mmio)) {
+ kvm_debug("Unable to decode inst: %#08lx (cpsr: %#08x (T=0)"
+ "pc: %#08x)\n",
+ instr, *vcpu_cpsr(vcpu), *vcpu_pc(vcpu));
+ kvm_inject_dabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ } else if (is_thumb && !kvm_decode_thumb_ls(vcpu, instr, mmio)) {
+ kvm_debug("Unable to decode inst: %#08lx (cpsr: %#08x (T=1)"
+ "pc: %#08x)\n",
+ instr, *vcpu_cpsr(vcpu), *vcpu_pc(vcpu));
+ kvm_inject_dabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ }
+
+ /*
+ * The MMIO instruction is emulated and should not be re-executed
+ * in the guest.
+ */
+ kvm_skip_instr(vcpu, is_wide_instruction(instr));
+ return 0;
+}
+
/**
* adjust_itstate - adjust ITSTATE when emulating instructions in IT-block
* @vcpu: The VCPU pointer
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index d79f1d4..7c89708 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -188,6 +188,44 @@ after_vfp_restore:
clrex @ Clear exclusive monitor
bx lr @ return to IOCTL
+
+/********************************************************************
+ * Translate VA to PA
+ *
+ * u64 __kvm_va_to_pa(struct kvm_vcpu *vcpu, u32 va, bool priv)
+ *
+ * Arguments:
+ * r0: pointer to vcpu struct
+ * r1: virtual address to map (rounded to page)
+ * r2: 1 = P1 (read) mapping, 0 = P0 (read) mapping.
+ * Returns 64 bit PAR value.
+ */
+ENTRY(__kvm_va_to_pa)
+ push {r4-r12}
+
+ @ Fold flag into r1, easier than using stack.
+ cmp r2, #0
+ movne r2, #1
+ orr r1, r1, r2
+
+ @ This swaps too many registers, but we're in the slow path anyway.
+ read_cp15_state
+ write_cp15_state 1, r0
+
+ ands r2, r1, #1
+ bic r1, r1, r2
+ mcrne p15, 0, r1, c7, c8, 0 @ VA to PA, ATS1CPR
+ mcreq p15, 0, r1, c7, c8, 2 @ VA to PA, ATS1CUR
+ isb
+
+ @ Restore host state.
+ read_cp15_state 1, r0
+ write_cp15_state
+
+ mrrc p15, 0, r0, r1, c7 @ PAR
+ pop {r4-r12}
+ bx lr
+
ENTRY(kvm_call_hyp)
hvc #0
bx lr
diff --git a/arch/arm/kvm/mmio.c b/arch/arm/kvm/mmio.c
new file mode 100644
index 0000000..28bd5eb
--- /dev/null
+++ b/arch/arm/kvm/mmio.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) 2012 - Virtual Open Systems and Columbia University
+ * Author: Christoffer Dall <c.dall@virtualopensystems.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <asm/kvm_mmio.h>
+#include <asm/kvm_emulate.h>
+#include <trace/events/kvm.h>
+
+#include "trace.h"
+
+/**
+ * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation
+ * @vcpu: The VCPU pointer
+ * @run: The VCPU run struct containing the mmio data
+ *
+ * This should only be called after returning from userspace for MMIO load
+ * emulation.
+ */
+int kvm_handle_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+ __u32 *dest;
+ unsigned int len;
+ int mask;
+
+ if (!run->mmio.is_write) {
+ dest = vcpu_reg(vcpu, vcpu->arch.mmio.rd);
+ memset(dest, 0, sizeof(int));
+
+ len = run->mmio.len;
+ if (len > 4)
+ return -EINVAL;
+
+ memcpy(dest, run->mmio.data, len);
+
+ trace_kvm_mmio(KVM_TRACE_MMIO_READ, len, run->mmio.phys_addr,
+ *((u64 *)run->mmio.data));
+
+ if (vcpu->arch.mmio.sign_extend && len < 4) {
+ mask = 1U << ((len * 8) - 1);
+ *dest = (*dest ^ mask) - mask;
+ }
+ }
+
+ return 0;
+}
+
+static int decode_hsr(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
+ struct kvm_exit_mmio *mmio)
+{
+ unsigned long rd, len;
+ bool is_write, sign_extend;
+
+ if ((vcpu->arch.hsr >> 8) & 1) {
+ /* cache operation on I/O addr, tell guest unsupported */
+ kvm_inject_dabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ }
+
+ if ((vcpu->arch.hsr >> 7) & 1) {
+ /* page table accesses IO mem: tell guest to fix its TTBR */
+ kvm_inject_dabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ }
+
+ switch ((vcpu->arch.hsr >> 22) & 0x3) {
+ case 0:
+ len = 1;
+ break;
+ case 1:
+ len = 2;
+ break;
+ case 2:
+ len = 4;
+ break;
+ default:
+ kvm_err("Hardware is weird: SAS 0b11 is reserved\n");
+ return -EFAULT;
+ }
+
+ is_write = vcpu->arch.hsr & HSR_WNR;
+ sign_extend = vcpu->arch.hsr & HSR_SSE;
+ rd = (vcpu->arch.hsr & HSR_SRT_MASK) >> HSR_SRT_SHIFT;
+
+ if (kvm_vcpu_reg_is_pc(vcpu, rd)) {
+ /* IO memory trying to read/write pc */
+ kvm_inject_pabt(vcpu, vcpu->arch.hxfar);
+ return 1;
+ }
+
+ mmio->is_write = is_write;
+ mmio->phys_addr = fault_ipa;
+ mmio->len = len;
+ vcpu->arch.mmio.sign_extend = sign_extend;
+ vcpu->arch.mmio.rd = rd;
+
+ /*
+ * The MMIO instruction is emulated and should not be re-executed
+ * in the guest.
+ */
+ kvm_skip_instr(vcpu, (vcpu->arch.hsr >> 25) & 1);
+ return 0;
+}
+
+int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ phys_addr_t fault_ipa, struct kvm_memory_slot *memslot)
+{
+ struct kvm_exit_mmio mmio;
+ unsigned long rd;
+ int ret;
+
+ /*
+ * Prepare MMIO operation. First stash it in a private
+ * structure that we can use for in-kernel emulation. If the
+ * kernel can't handle it, copy it into run->mmio and let user
+ * space do its magic.
+ */
+
+ if (vcpu->arch.hsr & HSR_ISV)
+ ret = decode_hsr(vcpu, fault_ipa, &mmio);
+ else
+ ret = kvm_emulate_mmio_ls(vcpu, fault_ipa, &mmio);
+
+ if (ret != 0)
+ return ret;
+
+ rd = vcpu->arch.mmio.rd;
+ trace_kvm_mmio((mmio.is_write) ? KVM_TRACE_MMIO_WRITE :
+ KVM_TRACE_MMIO_READ_UNSATISFIED,
+ mmio.len, fault_ipa,
+ (mmio.is_write) ? *vcpu_reg(vcpu, rd) : 0);
+
+ if (mmio.is_write)
+ memcpy(mmio.data, vcpu_reg(vcpu, rd), mmio.len);
+
+ kvm_prepare_mmio(run, &mmio);
+ return 0;
+}
+
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 9e2230d..cb03d45 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -19,11 +19,13 @@
#include <linux/mman.h>
#include <linux/kvm_host.h>
#include <linux/io.h>
+#include <trace/events/kvm.h>
#include <asm/idmap.h>
#include <asm/pgalloc.h>
#include <asm/cacheflush.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
+#include <asm/kvm_mmio.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/mach/map.h>
@@ -636,8 +638,9 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
return -EFAULT;
}
- kvm_pr_unimpl("I/O address abort...");
- return 0;
+ /* Adjust page offset */
+ fault_ipa |= vcpu->arch.hxfar & ~PAGE_MASK;
+ return io_mem_abort(vcpu, run, fault_ipa, memslot);
}
memslot = gfn_to_memslot(vcpu->kvm, gfn);
diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h
index e2a9d2e..c3d05f4 100644
--- a/arch/arm/kvm/trace.h
+++ b/arch/arm/kvm/trace.h
@@ -90,6 +90,27 @@ TRACE_EVENT(kvm_irq_line,
__entry->type, __entry->vcpu_idx, __entry->irq_num, __entry->level)
);
+TRACE_EVENT(kvm_mmio_emulate,
+ TP_PROTO(unsigned long vcpu_pc, unsigned long instr,
+ unsigned long cpsr),
+ TP_ARGS(vcpu_pc, instr, cpsr),
+
+ TP_STRUCT__entry(
+ __field( unsigned long, vcpu_pc )
+ __field( unsigned long, instr )
+ __field( unsigned long, cpsr )
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_pc = vcpu_pc;
+ __entry->instr = instr;
+ __entry->cpsr = cpsr;
+ ),
+
+ TP_printk("Emulate MMIO at: 0x%08lx (instr: %08lx, cpsr: %08lx)",
+ __entry->vcpu_pc, __entry->instr, __entry->cpsr)
+);
+
/* Architecturally implementation defined CP15 register access */
TRACE_EVENT(kvm_emulate_cp15_imp,
TP_PROTO(unsigned long Op1, unsigned long Rt1, unsigned long CRn,
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