diff options
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu.c | 24 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/mmu_internal.h | 20 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 102 | ||||
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.h | 5 |
5 files changed, 146 insertions, 6 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f6d47ac74a52..082684ce2d1b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1004,6 +1004,7 @@ struct kvm_arch { * operations. */ bool tdp_mmu_enabled; + struct list_head tdp_mmu_roots; }; struct kvm_vm_stat { diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 2afaf17284bb..017d37b19cf3 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -185,7 +185,7 @@ struct kvm_shadow_walk_iterator { __shadow_walk_next(&(_walker), spte)) static struct kmem_cache *pte_list_desc_cache; -static struct kmem_cache *mmu_page_header_cache; +struct kmem_cache *mmu_page_header_cache; static struct percpu_counter kvm_total_used_mmu_pages; static void mmu_spte_set(u64 *sptep, u64 spte); @@ -3132,9 +3132,13 @@ static void mmu_free_root_page(struct kvm *kvm, hpa_t *root_hpa, return; sp = to_shadow_page(*root_hpa & PT64_BASE_ADDR_MASK); - --sp->root_count; - if (!sp->root_count && sp->role.invalid) - kvm_mmu_prepare_zap_page(kvm, sp, invalid_list); + + if (kvm_mmu_put_root(kvm, sp)) { + if (sp->tdp_mmu_page) + kvm_tdp_mmu_free_root(kvm, sp); + else if (sp->role.invalid) + kvm_mmu_prepare_zap_page(kvm, sp, invalid_list); + } *root_hpa = INVALID_PAGE; } @@ -3224,8 +3228,16 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) hpa_t root; unsigned i; - if (shadow_root_level >= PT64_ROOT_4LEVEL) { - root = mmu_alloc_root(vcpu, 0, 0, shadow_root_level, true); + if (vcpu->kvm->arch.tdp_mmu_enabled) { + root = kvm_tdp_mmu_get_vcpu_root_hpa(vcpu); + + if (!VALID_PAGE(root)) + return -ENOSPC; + vcpu->arch.mmu->root_hpa = root; + } else if (shadow_root_level >= PT64_ROOT_4LEVEL) { + root = mmu_alloc_root(vcpu, 0, 0, shadow_root_level, + true); + if (!VALID_PAGE(root)) return -ENOSPC; vcpu->arch.mmu->root_hpa = root; diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index fc72f199eaa6..6665b10288ce 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -55,8 +55,12 @@ struct kvm_mmu_page { /* Number of writes since the last time traversal visited this page. */ atomic_t write_flooding_count; + + bool tdp_mmu_page; }; +extern struct kmem_cache *mmu_page_header_cache; + static inline struct kvm_mmu_page *to_shadow_page(hpa_t shadow_page) { struct page *page = pfn_to_page(shadow_page >> PAGE_SHIFT); @@ -89,4 +93,20 @@ void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, struct kvm_memory_slot *slot, u64 gfn); +static inline void kvm_mmu_get_root(struct kvm *kvm, struct kvm_mmu_page *sp) +{ + BUG_ON(!sp->root_count); + lockdep_assert_held(&kvm->mmu_lock); + + ++sp->root_count; +} + +static inline bool kvm_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *sp) +{ + lockdep_assert_held(&kvm->mmu_lock); + --sp->root_count; + + return !sp->root_count; +} + #endif /* __KVM_X86_MMU_INTERNAL_H */ diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index e567e8aa61a1..76ebb5898dd7 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -1,6 +1,9 @@ // SPDX-License-Identifier: GPL-2.0 +#include "mmu.h" +#include "mmu_internal.h" #include "tdp_mmu.h" +#include "spte.h" static bool __read_mostly tdp_mmu_enabled = false; @@ -21,10 +24,109 @@ void kvm_mmu_init_tdp_mmu(struct kvm *kvm) /* This should not be changed for the lifetime of the VM. */ kvm->arch.tdp_mmu_enabled = true; + + INIT_LIST_HEAD(&kvm->arch.tdp_mmu_roots); } void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) { if (!kvm->arch.tdp_mmu_enabled) return; + + WARN_ON(!list_empty(&kvm->arch.tdp_mmu_roots)); +} + +#define for_each_tdp_mmu_root(_kvm, _root) \ + list_for_each_entry(_root, &_kvm->arch.tdp_mmu_roots, link) + +bool is_tdp_mmu_root(struct kvm *kvm, hpa_t hpa) +{ + struct kvm_mmu_page *sp; + + sp = to_shadow_page(hpa); + + return sp->tdp_mmu_page && sp->root_count; +} + +void kvm_tdp_mmu_free_root(struct kvm *kvm, struct kvm_mmu_page *root) +{ + lockdep_assert_held(&kvm->mmu_lock); + + WARN_ON(root->root_count); + WARN_ON(!root->tdp_mmu_page); + + list_del(&root->link); + + free_page((unsigned long)root->spt); + kmem_cache_free(mmu_page_header_cache, root); +} + +static union kvm_mmu_page_role page_role_for_level(struct kvm_vcpu *vcpu, + int level) +{ + union kvm_mmu_page_role role; + + role = vcpu->arch.mmu->mmu_role.base; + role.level = level; + role.direct = true; + role.gpte_is_8_bytes = true; + role.access = ACC_ALL; + + return role; +} + +static struct kvm_mmu_page *alloc_tdp_mmu_page(struct kvm_vcpu *vcpu, gfn_t gfn, + int level) +{ + struct kvm_mmu_page *sp; + + sp = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache); + sp->spt = kvm_mmu_memory_cache_alloc(&vcpu->arch.mmu_shadow_page_cache); + set_page_private(virt_to_page(sp->spt), (unsigned long)sp); + + sp->role.word = page_role_for_level(vcpu, level).word; + sp->gfn = gfn; + sp->tdp_mmu_page = true; + + return sp; +} + +static struct kvm_mmu_page *get_tdp_mmu_vcpu_root(struct kvm_vcpu *vcpu) +{ + union kvm_mmu_page_role role; + struct kvm *kvm = vcpu->kvm; + struct kvm_mmu_page *root; + + role = page_role_for_level(vcpu, vcpu->arch.mmu->shadow_root_level); + + spin_lock(&kvm->mmu_lock); + + /* Check for an existing root before allocating a new one. */ + for_each_tdp_mmu_root(kvm, root) { + if (root->role.word == role.word) { + kvm_mmu_get_root(kvm, root); + spin_unlock(&kvm->mmu_lock); + return root; + } + } + + root = alloc_tdp_mmu_page(vcpu, 0, vcpu->arch.mmu->shadow_root_level); + root->root_count = 1; + + list_add(&root->link, &kvm->arch.tdp_mmu_roots); + + spin_unlock(&kvm->mmu_lock); + + return root; +} + +hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu) +{ + struct kvm_mmu_page *root; + + root = get_tdp_mmu_vcpu_root(vcpu); + if (!root) + return INVALID_PAGE; + + return __pa(root->spt); } diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h index cd4a562a70e9..ac0ef9129442 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.h +++ b/arch/x86/kvm/mmu/tdp_mmu.h @@ -7,4 +7,9 @@ void kvm_mmu_init_tdp_mmu(struct kvm *kvm); void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm); + +bool is_tdp_mmu_root(struct kvm *kvm, hpa_t root); +hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu); +void kvm_tdp_mmu_free_root(struct kvm *kvm, struct kvm_mmu_page *root); + #endif /* __KVM_X86_MMU_TDP_MMU_H */ |