[Qemu-devel] [PATCH v2 4/9] provide in-kernel apic

[Glauber Costa <glommer@redhat.com>]

This patch provides kvm with an in-kernel apic. 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/apic.c         |  135 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 kvm.h             |    3 +
 target-i386/kvm.c |   18 +++++++
 3 files changed, 152 insertions(+), 4 deletions(-)

diff --git a/hw/apic.c b/hw/apic.c
index c89008e..5635607 100644
--- a/hw/apic.c
+++ b/hw/apic.c
@@ -299,7 +299,11 @@ void cpu_set_apic_base(CPUState *env, uint64_t val)
 #endif
     if (!s)
         return;
-    s->apicbase = (val & 0xfffff000) |
+
+    if (kvm_enabled() && kvm_irqchip_in_kernel())
+        s->apicbase = val;
+    else
+        s->apicbase = (val & 0xfffff000) |
         (s->apicbase & (MSR_IA32_APICBASE_BSP | MSR_IA32_APICBASE_ENABLE));
     /* if disabled, cannot be enabled again */
     if (!(val & MSR_IA32_APICBASE_ENABLE)) {
@@ -497,6 +501,13 @@ void apic_init_reset(CPUState *env)
     s->wait_for_sipi = 1;
 
     env->halted = !(s->apicbase & MSR_IA32_APICBASE_BSP);
+
+#ifdef KVM_CAP_MP_STATE
+    if (kvm_enabled() && kvm_irqchip_in_kernel())
+        env->mp_state
+            = env->halted ? KVM_MP_STATE_UNINITIALIZED : KVM_MP_STATE_RUNNABLE;
+#endif
+
 }
 
 static void apic_startup(APICState *s, int vector_num)
@@ -903,12 +914,120 @@ static int apic_load_old(QEMUFile *f, void *opaque, int version_id)
     return 0;
 }
 
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+static inline uint32_t kapic_reg(struct kvm_lapic_state *kapic, int reg_id)
+{
+    return *((uint32_t *) (kapic->regs + (reg_id << 4)));
+}
+
+static inline void kapic_set_reg(struct kvm_lapic_state *kapic,
+                                 int reg_id, uint32_t val)
+{
+    *((uint32_t *) (kapic->regs + (reg_id << 4))) = val;
+}
+#endif
+
+static int kvm_kernel_lapic_load_from_user(APICState *s)
+{
+    int r = 0;
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+    struct kvm_lapic_state apic;
+    struct kvm_lapic_state *klapic = &apic;
+    int i;
+
+    if (!(kvm_enabled() && kvm_irqchip_in_kernel()))
+        return 0;
+
+    memset(klapic, 0, sizeof apic);
+    kapic_set_reg(klapic, 0x2, s->id << 24);
+    kapic_set_reg(klapic, 0x8, s->tpr);
+    kapic_set_reg(klapic, 0xd, s->log_dest << 24);
+    kapic_set_reg(klapic, 0xe, s->dest_mode << 28 | 0x0fffffff);
+    kapic_set_reg(klapic, 0xf, s->spurious_vec);
+    for (i = 0; i < 8; i++) {
+        kapic_set_reg(klapic, 0x10 + i, s->isr[i]);
+        kapic_set_reg(klapic, 0x18 + i, s->tmr[i]);
+        kapic_set_reg(klapic, 0x20 + i, s->irr[i]);
+    }
+    kapic_set_reg(klapic, 0x28, s->esr);
+    kapic_set_reg(klapic, 0x30, s->icr[0]);
+    kapic_set_reg(klapic, 0x31, s->icr[1]);
+    for (i = 0; i < APIC_LVT_NB; i++)
+        kapic_set_reg(klapic, 0x32 + i, s->lvt[i]);
+    kapic_set_reg(klapic, 0x38, s->initial_count);
+    kapic_set_reg(klapic, 0x3e, s->divide_conf);
+
+    r = kvm_set_lapic(s->cpu_env, klapic);
+#endif
+    return r;
+}
+
+static void kvm_kernel_lapic_save_to_user(APICState *s)
+{
+#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_I386)
+    struct kvm_lapic_state apic;
+    struct kvm_lapic_state *kapic = &apic;
+    int i, v;
+
+    if (!(kvm_enabled() && kvm_irqchip_in_kernel()))
+        return;
+
+    kvm_get_lapic(s->cpu_env, kapic);
+
+    s->id = kapic_reg(kapic, 0x2) >> 24;
+    s->tpr = kapic_reg(kapic, 0x8);
+    s->arb_id = kapic_reg(kapic, 0x9);
+    s->log_dest = kapic_reg(kapic, 0xd) >> 24;
+    s->dest_mode = kapic_reg(kapic, 0xe) >> 28;
+    s->spurious_vec = kapic_reg(kapic, 0xf);
+    for (i = 0; i < 8; i++) {
+        s->isr[i] = kapic_reg(kapic, 0x10 + i);
+        s->tmr[i] = kapic_reg(kapic, 0x18 + i);
+        s->irr[i] = kapic_reg(kapic, 0x20 + i);
+    }
+    s->esr = kapic_reg(kapic, 0x28);
+    s->icr[0] = kapic_reg(kapic, 0x30);
+    s->icr[1] = kapic_reg(kapic, 0x31);
+    for (i = 0; i < APIC_LVT_NB; i++)
+    s->lvt[i] = kapic_reg(kapic, 0x32 + i);
+    s->initial_count = kapic_reg(kapic, 0x38);
+    s->divide_conf = kapic_reg(kapic, 0x3e);
+
+    v = (s->divide_conf & 3) | ((s->divide_conf >> 1) & 4);
+    s->count_shift = (v + 1) & 7;
+
+    s->initial_count_load_time = qemu_get_clock(vm_clock);
+    apic_timer_update(s, s->initial_count_load_time);
+#endif
+}
+
+static void qemu_kvm_load_lapic(CPUState *env)
+{
+    kvm_kernel_lapic_load_from_user(env->apic_state);
+}
+
+static void apic_pre_save(void *opaque)
+{
+    APICState *s = (void *)opaque;
+
+    kvm_kernel_lapic_save_to_user(s);
+}
+
+static int apic_post_load(void *opaque, int version_id)
+{
+    APICState *s = opaque;
+
+    return kvm_kernel_lapic_load_from_user(s);
+}
+
 static const VMStateDescription vmstate_apic = {
     .name = "apic",
     .version_id = 3,
     .minimum_version_id = 3,
     .minimum_version_id_old = 1,
     .load_state_old = apic_load_old,
+    .pre_save = apic_pre_save,
+    .post_load = apic_post_load,
     .fields      = (VMStateField []) {
         VMSTATE_UINT32(apicbase, APICState),
         VMSTATE_UINT8(id, APICState),
@@ -933,9 +1052,8 @@ static const VMStateDescription vmstate_apic = {
     }
 };
 
-static void apic_reset(void *opaque)
+static void apic_do_reset(APICState *s)
 {
-    APICState *s = opaque;
     int bsp;
 
     cpu_synchronize_state(s->cpu_env);
@@ -957,6 +1075,15 @@ static void apic_reset(void *opaque)
     }
 }
 
+static void apic_reset(void *opaque)
+{
+    APICState *s = opaque;
+
+    apic_do_reset(s);
+
+    qemu_kvm_load_lapic(s->cpu_env);
+}
+
 static CPUReadMemoryFunc * const apic_mem_read[3] = {
     apic_mem_readb,
     apic_mem_readw,
@@ -981,7 +1108,7 @@ int apic_init(CPUState *env)
     s->id = env->cpuid_apic_id;
     s->cpu_env = env;
 
-    apic_reset(s);
+    apic_do_reset(s);
     msix_supported = 1;
 
     /* XXX: mapping more APICs at the same memory location */
diff --git a/kvm.h b/kvm.h
index 8d4afa0..099b55e 100644
--- a/kvm.h
+++ b/kvm.h
@@ -97,6 +97,9 @@ int kvm_arch_init(KVMState *s, int smp_cpus);
 
 int kvm_arch_init_vcpu(CPUState *env);
 
+int kvm_set_lapic(CPUState *env, struct kvm_lapic_state *s);
+int kvm_get_lapic(CPUState *env, struct kvm_lapic_state *s);
+
 struct kvm_guest_debug;
 struct kvm_debug_exit_arch;
 
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 7010999..d485d4c 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -957,3 +957,21 @@ void kvm_arch_update_guest_debug(CPUState *env, struct kvm_guest_debug *dbg)
     }
 }
 #endif /* KVM_CAP_SET_GUEST_DEBUG */
+
+#ifdef KVM_CAP_IRQCHIP
+int kvm_set_lapic(CPUState *env, struct kvm_lapic_state *s)
+{
+    if (!kvm_irqchip_in_kernel())
+        return 0;
+
+    return kvm_vcpu_ioctl(env, KVM_SET_LAPIC, s);
+}
+
+int kvm_get_lapic(CPUState *env, struct kvm_lapic_state *s)
+{
+    if (!kvm_irqchip_in_kernel())
+        return 0;
+
+    return kvm_vcpu_ioctl(env, KVM_GET_LAPIC, s);
+}
+#endif
-- 
1.6.2.5