From fb3f0f51d92d1496f9628ca6f0fb06a48dc9ed2a Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 27 Jul 2007 17:16:56 +1000 Subject: KVM: Dynamically allocate vcpus This patch converts the vcpus array in "struct kvm" to a pointer array, and changes the "vcpu_create" and "vcpu_setup" hooks into one "vcpu_create" call which does the allocation and initialization of the vcpu (calling back into the kvm_vcpu_init core helper). Signed-off-by: Rusty Russell Signed-off-by: Avi Kivity --- drivers/kvm/kvm_main.c | 198 +++++++++++++++++++++++++------------------------ 1 file changed, 103 insertions(+), 95 deletions(-) (limited to 'drivers/kvm/kvm_main.c') diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index bf8b8f030192..69d9ab4e7cb4 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -266,8 +266,10 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) atomic_set(&completed, 0); cpus_clear(cpus); needed = 0; - for (i = 0; i < kvm->nvcpus; ++i) { - vcpu = &kvm->vcpus[i]; + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + vcpu = kvm->vcpus[i]; + if (!vcpu) + continue; if (test_and_set_bit(KVM_TLB_FLUSH, &vcpu->requests)) continue; cpu = vcpu->cpu; @@ -291,10 +293,61 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) } } +int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) +{ + struct page *page; + int r; + + mutex_init(&vcpu->mutex); + vcpu->cpu = -1; + vcpu->mmu.root_hpa = INVALID_PAGE; + vcpu->kvm = kvm; + vcpu->vcpu_id = id; + + page = alloc_page(GFP_KERNEL | __GFP_ZERO); + if (!page) { + r = -ENOMEM; + goto fail; + } + vcpu->run = page_address(page); + + page = alloc_page(GFP_KERNEL | __GFP_ZERO); + if (!page) { + r = -ENOMEM; + goto fail_free_run; + } + vcpu->pio_data = page_address(page); + + vcpu->host_fx_image = (char*)ALIGN((hva_t)vcpu->fx_buf, + FX_IMAGE_ALIGN); + vcpu->guest_fx_image = vcpu->host_fx_image + FX_IMAGE_SIZE; + + r = kvm_mmu_create(vcpu); + if (r < 0) + goto fail_free_pio_data; + + return 0; + +fail_free_pio_data: + free_page((unsigned long)vcpu->pio_data); +fail_free_run: + free_page((unsigned long)vcpu->run); +fail: + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(kvm_vcpu_init); + +void kvm_vcpu_uninit(struct kvm_vcpu *vcpu) +{ + kvm_mmu_destroy(vcpu); + free_page((unsigned long)vcpu->pio_data); + free_page((unsigned long)vcpu->run); +} +EXPORT_SYMBOL_GPL(kvm_vcpu_uninit); + static struct kvm *kvm_create_vm(void) { struct kvm *kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL); - int i; if (!kvm) return ERR_PTR(-ENOMEM); @@ -303,14 +356,6 @@ static struct kvm *kvm_create_vm(void) spin_lock_init(&kvm->lock); INIT_LIST_HEAD(&kvm->active_mmu_pages); kvm_io_bus_init(&kvm->mmio_bus); - for (i = 0; i < KVM_MAX_VCPUS; ++i) { - struct kvm_vcpu *vcpu = &kvm->vcpus[i]; - - mutex_init(&vcpu->mutex); - vcpu->cpu = -1; - vcpu->kvm = kvm; - vcpu->mmu.root_hpa = INVALID_PAGE; - } spin_lock(&kvm_lock); list_add(&kvm->vm_list, &vm_list); spin_unlock(&kvm_lock); @@ -367,30 +412,11 @@ static void free_pio_guest_pages(struct kvm_vcpu *vcpu) static void kvm_unload_vcpu_mmu(struct kvm_vcpu *vcpu) { - if (!vcpu->valid) - return; - vcpu_load(vcpu); kvm_mmu_unload(vcpu); vcpu_put(vcpu); } -static void kvm_free_vcpu(struct kvm_vcpu *vcpu) -{ - if (!vcpu->valid) - return; - - vcpu_load(vcpu); - kvm_mmu_destroy(vcpu); - vcpu_put(vcpu); - kvm_arch_ops->vcpu_free(vcpu); - free_page((unsigned long)vcpu->run); - vcpu->run = NULL; - free_page((unsigned long)vcpu->pio_data); - vcpu->pio_data = NULL; - free_pio_guest_pages(vcpu); -} - static void kvm_free_vcpus(struct kvm *kvm) { unsigned int i; @@ -399,9 +425,15 @@ static void kvm_free_vcpus(struct kvm *kvm) * Unpin any mmu pages first. */ for (i = 0; i < KVM_MAX_VCPUS; ++i) - kvm_unload_vcpu_mmu(&kvm->vcpus[i]); - for (i = 0; i < KVM_MAX_VCPUS; ++i) - kvm_free_vcpu(&kvm->vcpus[i]); + if (kvm->vcpus[i]) + kvm_unload_vcpu_mmu(kvm->vcpus[i]); + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + if (kvm->vcpus[i]) { + kvm_arch_ops->vcpu_free(kvm->vcpus[i]); + kvm->vcpus[i] = NULL; + } + } + } static int kvm_dev_release(struct inode *inode, struct file *filp) @@ -2372,77 +2404,47 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n) { int r; struct kvm_vcpu *vcpu; - struct page *page; - r = -EINVAL; if (!valid_vcpu(n)) - goto out; - - vcpu = &kvm->vcpus[n]; - vcpu->vcpu_id = n; - - mutex_lock(&vcpu->mutex); - - if (vcpu->valid) { - mutex_unlock(&vcpu->mutex); - return -EEXIST; - } - - page = alloc_page(GFP_KERNEL | __GFP_ZERO); - r = -ENOMEM; - if (!page) - goto out_unlock; - vcpu->run = page_address(page); - - page = alloc_page(GFP_KERNEL | __GFP_ZERO); - r = -ENOMEM; - if (!page) - goto out_free_run; - vcpu->pio_data = page_address(page); - - vcpu->host_fx_image = (char*)ALIGN((hva_t)vcpu->fx_buf, - FX_IMAGE_ALIGN); - vcpu->guest_fx_image = vcpu->host_fx_image + FX_IMAGE_SIZE; - vcpu->cr0 = 0x10; - - r = kvm_arch_ops->vcpu_create(vcpu); - if (r < 0) - goto out_free_vcpus; + return -EINVAL; - r = kvm_mmu_create(vcpu); - if (r < 0) - goto out_free_vcpus; + vcpu = kvm_arch_ops->vcpu_create(kvm, n); + if (IS_ERR(vcpu)) + return PTR_ERR(vcpu); - kvm_arch_ops->vcpu_load(vcpu); + vcpu_load(vcpu); r = kvm_mmu_setup(vcpu); - if (r >= 0) - r = kvm_arch_ops->vcpu_setup(vcpu); vcpu_put(vcpu); - if (r < 0) - goto out_free_vcpus; + goto free_vcpu; + spin_lock(&kvm->lock); + if (kvm->vcpus[n]) { + r = -EEXIST; + spin_unlock(&kvm->lock); + goto mmu_unload; + } + kvm->vcpus[n] = vcpu; + spin_unlock(&kvm->lock); + + /* Now it's all set up, let userspace reach it */ r = create_vcpu_fd(vcpu); if (r < 0) - goto out_free_vcpus; - - spin_lock(&kvm_lock); - if (n >= kvm->nvcpus) - kvm->nvcpus = n + 1; - spin_unlock(&kvm_lock); + goto unlink; + return r; - vcpu->valid = 1; +unlink: + spin_lock(&kvm->lock); + kvm->vcpus[n] = NULL; + spin_unlock(&kvm->lock); - return r; +mmu_unload: + vcpu_load(vcpu); + kvm_mmu_unload(vcpu); + vcpu_put(vcpu); -out_free_vcpus: - kvm_free_vcpu(vcpu); -out_free_run: - free_page((unsigned long)vcpu->run); - vcpu->run = NULL; -out_unlock: - mutex_unlock(&vcpu->mutex); -out: +free_vcpu: + kvm_arch_ops->vcpu_free(vcpu); return r; } @@ -2935,9 +2937,12 @@ static void decache_vcpus_on_cpu(int cpu) int i; spin_lock(&kvm_lock); - list_for_each_entry(vm, &vm_list, vm_list) + list_for_each_entry(vm, &vm_list, vm_list) { + spin_lock(&vm->lock); for (i = 0; i < KVM_MAX_VCPUS; ++i) { - vcpu = &vm->vcpus[i]; + vcpu = vm->vcpus[i]; + if (!vcpu) + continue; /* * If the vcpu is locked, then it is running on some * other cpu and therefore it is not cached on the @@ -2954,6 +2959,8 @@ static void decache_vcpus_on_cpu(int cpu) mutex_unlock(&vcpu->mutex); } } + spin_unlock(&vm->lock); + } spin_unlock(&kvm_lock); } @@ -3078,8 +3085,9 @@ static u64 stat_get(void *_offset) spin_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) for (i = 0; i < KVM_MAX_VCPUS; ++i) { - vcpu = &kvm->vcpus[i]; - total += *(u32 *)((void *)vcpu + offset); + vcpu = kvm->vcpus[i]; + if (vcpu) + total += *(u32 *)((void *)vcpu + offset); } spin_unlock(&kvm_lock); return total; -- cgit v1.2.1