[Qemu-devel] [PATCH 1/6] provide in-kernel ioapic

[Glauber Costa <glommer@redhat.com>]

This patch provides kvm with an in-kernel ioapic. We are currently not enabling it.
The code is heavily based on what's in qemu-kvm.git.

Signed-off-by: Glauber Costa <glommer@redhat.com>
---
 hw/ioapic.c |   85 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 kvm-all.c   |   20 ++++++++++++++
 kvm.h       |    4 +++
 3 files changed, 108 insertions(+), 1 deletions(-)

diff --git a/hw/ioapic.c b/hw/ioapic.c
index b0ad78f..3af86f1 100644
--- a/hw/ioapic.c
+++ b/hw/ioapic.c
@@ -24,10 +24,12 @@
 #include "pc.h"
 #include "qemu-timer.h"
 #include "host-utils.h"
+#include "kvm.h"
 
 //#define DEBUG_IOAPIC
 
 #define IOAPIC_NUM_PINS			0x18
+#define IOAPIC_DEFAULT_BASE_ADDRESS  0xfec00000
 #define IOAPIC_LVT_MASKED 		(1<<16)
 
 #define IOAPIC_TRIGGER_EDGE		0
@@ -191,6 +193,79 @@ static void ioapic_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t va
     }
 }
 
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+static void kvm_kernel_ioapic_load_from_user(IOAPICState *s)
+{
+    struct kvm_irqchip chip;
+    struct kvm_ioapic_state *kioapic;
+    int i;
+
+    chip.chip_id = KVM_IRQCHIP_IOAPIC;
+    kioapic = &chip.chip.ioapic;
+
+    kioapic->id = s->id;
+    kioapic->ioregsel = s->ioregsel;
+    kioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
+    kioapic->irr = s->irr;
+    for (i = 0; i < IOAPIC_NUM_PINS; i++) {
+        kioapic->redirtbl[i].bits = s->ioredtbl[i];
+    }
+
+    kvm_set_irqchip(&chip);
+}
+
+static void kvm_kernel_ioapic_save_to_user(IOAPICState *s)
+{
+    struct kvm_irqchip chip;
+    struct kvm_ioapic_state *kioapic;
+    int i;
+
+    chip.chip_id = KVM_IRQCHIP_IOAPIC;
+    kvm_get_irqchip(&chip);
+    kioapic = &chip.chip.ioapic;
+
+    s->id = kioapic->id;
+    s->ioregsel = kioapic->ioregsel;
+    s->irr = kioapic->irr;
+    for (i = 0; i < IOAPIC_NUM_PINS; i++) {
+        s->ioredtbl[i] = kioapic->redirtbl[i].bits;
+    }
+}
+#endif
+
+static void ioapic_pre_save(const void *opaque)
+{
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+    IOAPICState *s = (void *)opaque;
+
+    if (kvm_enabled() && kvm_irqchip_in_kernel()) {
+        kvm_kernel_ioapic_save_to_user(s);
+    }
+#endif
+}
+
+static int ioapic_pre_load(void *opaque)
+{
+    IOAPICState *s = opaque;
+
+    /* in case we are doing version 1, we just set these to sane values */
+    s->irr = 0;
+    return 0;
+}
+
+static int ioapic_post_load(void *opaque)
+{
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+    IOAPICState *s = opaque;
+
+    if (kvm_enabled() && kvm_irqchip_in_kernel()) {
+        kvm_kernel_ioapic_load_from_user(s);
+    }
+#endif
+    return 0;
+}
+
+
 static const VMStateDescription vmstate_ioapic = {
     .name = "ioapic",
     .version_id = 1,
@@ -201,7 +276,10 @@ static const VMStateDescription vmstate_ioapic = {
         VMSTATE_UINT8(ioregsel, IOAPICState),
         VMSTATE_UINT64_ARRAY(ioredtbl, IOAPICState, IOAPIC_NUM_PINS),
         VMSTATE_END_OF_LIST()
-    }
+    },
+    .pre_load = ioapic_pre_load,
+    .post_load = ioapic_post_load,
+    .pre_save = ioapic_pre_save,
 };
 
 static void ioapic_reset(void *opaque)
@@ -212,6 +290,11 @@ static void ioapic_reset(void *opaque)
     memset(s, 0, sizeof(*s));
     for(i = 0; i < IOAPIC_NUM_PINS; i++)
         s->ioredtbl[i] = 1 << 16; /* mask LVT */
+#ifdef KVM_CAP_IRQCHIP
+    if (kvm_enabled() && kvm_irqchip_in_kernel()) {
+        kvm_kernel_ioapic_load_from_user(s);
+    }
+#endif
 }
 
 static CPUReadMemoryFunc * const ioapic_mem_read[3] = {
diff --git a/kvm-all.c b/kvm-all.c
index f8a05cc..ff439a5 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -411,6 +411,26 @@ int kvm_check_extension(KVMState *s, unsigned int extension)
     return ret;
 }
 
+#ifdef KVM_CAP_IRQCHIP
+int kvm_set_irqchip(struct kvm_irqchip *chip)
+{
+    if (!kvm_state->irqchip_in_kernel) {
+        return 0;
+    }
+
+    return kvm_vm_ioctl(kvm_state, KVM_SET_IRQCHIP, chip);
+}
+
+int kvm_get_irqchip(struct kvm_irqchip *chip)
+{
+    if (!kvm_state->irqchip_in_kernel) {
+        return 0;
+    }
+
+    return kvm_vm_ioctl(kvm_state, KVM_GET_IRQCHIP, chip);
+}
+#endif
+
 int kvm_init(int smp_cpus)
 {
     static const char upgrade_note[] =
diff --git a/kvm.h b/kvm.h
index e7d5beb..8d4afa0 100644
--- a/kvm.h
+++ b/kvm.h
@@ -16,6 +16,7 @@
 
 #include "config.h"
 #include "qemu-queue.h"
+#include <linux/kvm.h>
 
 #ifdef CONFIG_KVM
 extern int kvm_allowed;
@@ -63,6 +64,9 @@ int kvm_update_guest_debug(CPUState *env, unsigned long reinject_trap);
 int kvm_pit_in_kernel(void);
 int kvm_irqchip_in_kernel(void);
 
+int kvm_set_irqchip(struct kvm_irqchip *chip);
+int kvm_get_irqchip(struct kvm_irqchip *chip);
+
 /* internal API */
 
 struct KVMState;
-- 
1.6.2.5