KVM: Introduce kvm_vcpu_is_bsp() function.

Use it instead of open code "vcpu_id zero is BSP" assumption.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

11 files changed, 28 insertions, 18 deletions

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index 8dde36953af3..4082665ace0a 100644
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -1216,7 +1216,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
         if (IS_ERR(vmm_vcpu))
                 return PTR_ERR(vmm_vcpu);
 
-        if (vcpu->vcpu_id == 0) {
+        if (kvm_vcpu_is_bsp(vcpu)) {
                 vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
 
                 /*Set entry address for first run.*/
diff --git a/arch/ia64/kvm/vcpu.c b/arch/ia64/kvm/vcpu.c
index cc406d064a09..61a3320b62c1 100644
--- a/arch/ia64/kvm/vcpu.c
+++ b/arch/ia64/kvm/vcpu.c
@@ -830,7 +830,7 @@ static void vcpu_set_itc(struct kvm_vcpu *vcpu, u64 val)
 
         kvm = (struct kvm *)KVM_VM_BASE;
 
-        if (vcpu->vcpu_id == 0) {
+        if (kvm_vcpu_is_bsp(vcpu)) {
                 for (i = 0; i < kvm->arch.online_vcpus; i++) {
                         v = (struct kvm_vcpu *)((char *)vcpu +
                                         sizeof(struct kvm_vcpu_data) * i);
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index 3837db65d33e..008a83185067 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -231,7 +231,7 @@ int pit_has_pending_timer(struct kvm_vcpu *vcpu)
 {
         struct kvm_pit *pit = vcpu->kvm->arch.vpit;
 
-        if (pit && vcpu->vcpu_id == 0 && pit->pit_state.irq_ack)
+        if (pit && kvm_vcpu_is_bsp(vcpu) && pit->pit_state.irq_ack)
                 return atomic_read(&pit->pit_state.pit_timer.pending);
         return 0;
 }
@@ -252,7 +252,7 @@ void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu)
         struct kvm_pit *pit = vcpu->kvm->arch.vpit;
         struct hrtimer *timer;
 
-        if (vcpu->vcpu_id != 0 || !pit)
+        if (!kvm_vcpu_is_bsp(vcpu) || !pit)
                 return;
 
         timer = &pit->pit_state.pit_timer.timer;
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index bf94a45f4f86..148c52a608d6 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -57,7 +57,7 @@ static void pic_unlock(struct kvm_pic *s)
         }
 
         if (wakeup) {
-                vcpu = s->kvm->vcpus[0];
+                vcpu = s->kvm->bsp_vcpu;
                 if (vcpu)
                         kvm_vcpu_kick(vcpu);
         }
@@ -254,7 +254,7 @@ void kvm_pic_reset(struct kvm_kpic_state *s)
 {
         int irq, irqbase, n;
         struct kvm *kvm = s->pics_state->irq_request_opaque;
-        struct kvm_vcpu *vcpu0 = kvm->vcpus[0];
+        struct kvm_vcpu *vcpu0 = kvm->bsp_vcpu;
 
         if (s == &s->pics_state->pics[0])
                 irqbase = 0;
@@ -512,7 +512,7 @@ static void picdev_read(struct kvm_io_device *this,
 static void pic_irq_request(void *opaque, int level)
 {
         struct kvm *kvm = opaque;
-        struct kvm_vcpu *vcpu = kvm->vcpus[0];
+        struct kvm_vcpu *vcpu = kvm->bsp_vcpu;
         struct kvm_pic *s = pic_irqchip(kvm);
         int irq = pic_get_irq(&s->pics[0]);
 
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 44f20cdb5709..b0661300eb28 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -793,7 +793,8 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
                 vcpu->arch.apic_base = value;
                 return;
         }
-        if (apic->vcpu->vcpu_id)
+
+        if (!kvm_vcpu_is_bsp(apic->vcpu))
                 value &= ~MSR_IA32_APICBASE_BSP;
 
         vcpu->arch.apic_base = value;
@@ -844,7 +845,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu)
         }
         update_divide_count(apic);
         atomic_set(&apic->lapic_timer.pending, 0);
-        if (vcpu->vcpu_id == 0)
+        if (kvm_vcpu_is_bsp(vcpu))
                 vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
         apic_update_ppr(apic);
 
@@ -985,7 +986,7 @@ int kvm_apic_accept_pic_intr(struct kvm_vcpu *vcpu)
         u32 lvt0 = apic_get_reg(vcpu->arch.apic, APIC_LVT0);
         int r = 0;
 
-        if (vcpu->vcpu_id == 0) {
+        if (kvm_vcpu_is_bsp(vcpu)) {
                 if (!apic_hw_enabled(vcpu->arch.apic))
                         r = 1;
                 if ((lvt0 & APIC_LVT_MASKED) == 0 &&
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7749b0692cb2..28b981409a8f 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -642,7 +642,7 @@ static int svm_vcpu_reset(struct kvm_vcpu *vcpu)
 
         init_vmcb(svm);
 
-        if (vcpu->vcpu_id != 0) {
+        if (!kvm_vcpu_is_bsp(vcpu)) {
                 kvm_rip_write(vcpu, 0);
                 svm->vmcb->save.cs.base = svm->vcpu.arch.sipi_vector << 12;
                 svm->vmcb->save.cs.selector = svm->vcpu.arch.sipi_vector << 8;
@@ -706,7 +706,7 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id)
         fx_init(&svm->vcpu);
         svm->vcpu.fpu_active = 1;
         svm->vcpu.arch.apic_base = 0xfee00000 | MSR_IA32_APICBASE_ENABLE;
-        if (svm->vcpu.vcpu_id == 0)
+        if (kvm_vcpu_is_bsp(&svm->vcpu))
                 svm->vcpu.arch.apic_base |= MSR_IA32_APICBASE_BSP;
 
         return &svm->vcpu;
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ae682929a642..c08bb4cf372e 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2411,7 +2411,7 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
         vmx->vcpu.arch.regs[VCPU_REGS_RDX] = get_rdx_init_val();
         kvm_set_cr8(&vmx->vcpu, 0);
         msr = 0xfee00000 | MSR_IA32_APICBASE_ENABLE;
-        if (vmx->vcpu.vcpu_id == 0)
+        if (kvm_vcpu_is_bsp(&vmx->vcpu))
                 msr |= MSR_IA32_APICBASE_BSP;
         kvm_set_apic_base(&vmx->vcpu, msr);
 
@@ -2422,7 +2422,7 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
          * GUEST_CS_BASE should really be 0xffff0000, but VT vm86 mode
          * insists on having GUEST_CS_BASE == GUEST_CS_SELECTOR << 4.  Sigh.
          */
-        if (vmx->vcpu.vcpu_id == 0) {
+        if (kvm_vcpu_is_bsp(&vmx->vcpu)) {
                 vmcs_write16(GUEST_CS_SELECTOR, 0xf000);
                 vmcs_writel(GUEST_CS_BASE, 0x000f0000);
         } else {
@@ -2451,7 +2451,7 @@ static int vmx_vcpu_reset(struct kvm_vcpu *vcpu)
         vmcs_writel(GUEST_SYSENTER_EIP, 0);
 
         vmcs_writel(GUEST_RFLAGS, 0x02);
-        if (vmx->vcpu.vcpu_id == 0)
+        if (kvm_vcpu_is_bsp(&vmx->vcpu))
                 kvm_rip_write(vcpu, 0xfff0);
         else
                 kvm_rip_write(vcpu, 0);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e877efa37620..d8adc1da76dd 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4330,7 +4330,7 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
         kvm_set_segment(vcpu, &sregs->ldt, VCPU_SREG_LDTR);
 
         /* Older userspace won't unhalt the vcpu on reset. */
-        if (vcpu->vcpu_id == 0 && kvm_rip_read(vcpu) == 0xfff0 &&
+        if (kvm_vcpu_is_bsp(vcpu) && kvm_rip_read(vcpu) == 0xfff0 &&
             sregs->cs.selector == 0xf000 && sregs->cs.base == 0xffff0000 &&
             !(vcpu->arch.cr0 & X86_CR0_PE))
                 vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
@@ -4601,7 +4601,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
         kvm = vcpu->kvm;
 
         vcpu->arch.mmu.root_hpa = INVALID_PAGE;
-        if (!irqchip_in_kernel(kvm) || vcpu->vcpu_id == 0)
+        if (!irqchip_in_kernel(kvm) || kvm_vcpu_is_bsp(vcpu))
                 vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
         else
                 vcpu->arch.mp_state = KVM_MP_STATE_UNINITIALIZED;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index a29ea030dd8e..a5bd429e9bd3 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -131,6 +131,7 @@ struct kvm {
         int nmemslots;
         struct kvm_memory_slot memslots[KVM_MEMORY_SLOTS +
                                         KVM_PRIVATE_MEM_SLOTS];
+        struct kvm_vcpu *bsp_vcpu;
         struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
         struct list_head vm_list;
         struct mutex lock;
@@ -549,4 +550,8 @@ static inline void kvm_irqfd_release(struct kvm *kvm) {}
 
 #endif /* CONFIG_HAVE_KVM_EVENTFD */
 
+static inline bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu)
+{
+        return vcpu->kvm->bsp_vcpu == vcpu;
+}
 #endif
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 2a5667173995..0532fa68f5d1 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -164,7 +164,9 @@ static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
         /* Always delivery PIT interrupt to vcpu 0 */
         if (irq == 0) {
                 irqe.dest_mode = 0; /* Physical mode. */
-                irqe.dest_id = ioapic->kvm->vcpus[0]->vcpu_id;
+                /* need to read apic_id from apic regiest since
+                 * it can be rewritten */
+                irqe.dest_id = ioapic->kvm->bsp_vcpu->vcpu_id;
         }
 #endif
         return kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0d481b282448..0d54edecbc70 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1747,6 +1747,8 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
                 goto vcpu_destroy;
         }
         kvm->vcpus[n] = vcpu;
+        if (n == 0)
+                kvm->bsp_vcpu = vcpu;
         mutex_unlock(&kvm->lock);
 
         /* Now it's all set up, let userspace reach it */