[PATCH 02/10] ARM: KVM: Initial VGIC infrastructure support

Christoffer Dall
2012-09-15T15:37:10Z

Wire the basic framework code for VGIC support. Nothing to enable
yet.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_host.h | 8 +++++
arch/arm/include/asm/kvm_vgic.h | 65 +++++++++++++++++++++++++++++++++++++++
arch/arm/kvm/arm.c | 20 +++++++++++-
arch/arm/kvm/interrupts.S | 18 +++++++++++
arch/arm/kvm/mmu.c | 3 ++
virt/kvm/kvm_main.c | 5 ++-
6 files changed, 116 insertions(+), 3 deletions(-)
create mode 100644 arch/arm/include/asm/kvm_vgic.h

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 2e3ac1c..97e0e5a 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -28,6 +28,8 @@
#define KVM_COALESCED_MMIO_PAGE_OFFSET 1
#define KVM_HAVE_ONE_REG

+#include <asm/kvm_vgic.h>
+
#define NUM_FEATURES 0

/* We don't currently support large pages. */
@@ -52,6 +54,9 @@ struct kvm_arch {

/* VTTBR value associated with above pgd and vmid */
u64 vttbr;
+
+ /* Interrupt controller */
+ struct vgic_dist vgic;
};

#define EXCEPTION_NONE 0
@@ -144,6 +149,9 @@ struct kvm_vcpu_arch {
struct vfp_hard_struct vfp_guest;
struct vfp_hard_struct *vfp_host;

+ /* VGIC state */
+ struct vgic_cpu vgic_cpu;
+
/*
* Anything that is not used directly from assembly code goes
* here.
diff --git a/arch/arm/include/asm/kvm_vgic.h b/arch/arm/include/asm/kvm_vgic.h
new file mode 100644
index 0000000..e1fd530
--- /dev/null
+++ b/arch/arm/include/asm/kvm_vgic.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.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, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef __ASM_ARM_KVM_VGIC_H
+#define __ASM_ARM_KVM_VGIC_H
+
+struct vgic_dist {
+};
+
+struct vgic_cpu {
+};
+
+struct kvm;
+struct kvm_vcpu;
+struct kvm_run;
+struct kvm_exit_mmio;
+
+#ifndef CONFIG_KVM_ARM_VGIC
+static inline int kvm_vgic_hyp_init(void)
+{
+ return 0;
+}
+
+static inline int kvm_vgic_init(struct kvm *kvm)
+{
+ return 0;
+}
+
+static inline void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) {}
+static inline void kvm_vgic_sync_to_cpu(struct kvm_vcpu *vcpu) {}
+static inline void kvm_vgic_sync_from_cpu(struct kvm_vcpu *vcpu) {}
+
+static inline int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
+{
+ return 0;
+}
+
+static inline bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
+ struct kvm_exit_mmio *mmio)
+{
+ return false;
+}
+
+static inline int irqchip_in_kernel(struct kvm *kvm)
+{
+ return 0;
+}
+#endif
+
+#endif
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index e6c3743..665c6bd 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -185,6 +185,9 @@ int kvm_dev_ioctl_check_extension(long ext)
{
int r;
switch (ext) {
+#ifdef CONFIG_KVM_ARM_VGIC
+ case KVM_CAP_IRQCHIP:
+#endif
case KVM_CAP_USER_MEMORY:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_ONE_REG:
@@ -298,6 +301,9 @@ int __attribute_const__ kvm_target_cpu(void)

int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
+ /* Set up VGIC */
+ kvm_vgic_vcpu_init(vcpu);
+
return 0;
}

@@ -357,7 +363,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
*/
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
- return !!v->arch.irq_lines;
+ return !!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v);
}

int kvm_arch_vcpu_in_guest_mode(struct kvm_vcpu *v)
@@ -625,6 +631,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
cond_resched();
update_vttbr(vcpu->kvm);

+ kvm_vgic_sync_to_cpu(vcpu);
+
local_irq_disable();

/*
@@ -637,6 +645,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)

if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
local_irq_enable();
+ kvm_vgic_sync_from_cpu(vcpu);
continue;
}

@@ -677,6 +686,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
* Back from guest
*************************************************************/

+ kvm_vgic_sync_from_cpu(vcpu);
+
ret = handle_exit(vcpu, run, ret);
}

@@ -949,6 +960,13 @@ static int init_hyp_mode(void)
}
}

+ /*
+ * Init HYP view of VGIC
+ */
+ err = kvm_vgic_hyp_init();
+ if (err)
+ goto out_free_mappings;
+
return 0;
out_free_vfp:
free_percpu(kvm_host_vfp_state);
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index ab78477..dad9df7 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -311,6 +311,20 @@ ENDPROC(__kvm_flush_vm_context)
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
@@ -388,6 +402,8 @@ ENTRY(__kvm_vcpu_run)
store_mode_state sp, irq
store_mode_state sp, fiq

+ restore_vgic_state r0
+
@ Store hardware CP15 state and load guest state
read_cp15_state
write_cp15_state 1, r0
@@ -505,6 +521,8 @@ after_vfp_restore:
read_cp15_state 1, r1
write_cp15_state

+ save_vgic_state r1
+
load_mode_state sp, fiq
load_mode_state sp, irq
load_mode_state sp, und
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index dc760bb..82d0edf 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -845,6 +845,9 @@ static int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
if (mmio.is_write)
memcpy(mmio.data, vcpu_reg(vcpu, rd), mmio.len);

+ if (vgic_handle_mmio(vcpu, run, &mmio))
+ return 1;
+
kvm_prepare_mmio(run, &mmio);
return 0;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 35885b2..dd8b115 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1881,12 +1881,13 @@ static long kvm_vcpu_ioctl(struct file *filp,
if (vcpu->kvm->mm != current->mm)
return -EIO;

-#if defined(CONFIG_S390) || defined(CONFIG_PPC)
+#if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_ARM)
/*
* Special cases: vcpu ioctls that are asynchronous to vcpu execution,
* so vcpu_load() would break it.
*/
- if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT)
+ if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_INTERRUPT ||
+ ioctl == KVM_IRQ_LINE)
return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
#endif