diff options
Diffstat (limited to 'arch/x86/kvm/mmu.c')
-rw-r--r-- | arch/x86/kvm/mmu.c | 150 |
1 files changed, 63 insertions, 87 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index f02b8edc3d4..22fae7593ee 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -111,9 +111,6 @@ module_param(oos_shadow, bool, 0644); #define PT64_LEVEL_SHIFT(level) \ (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS) -#define PT64_LEVEL_MASK(level) \ - (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level)) - #define PT64_INDEX(address, level)\ (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1)) @@ -123,8 +120,6 @@ module_param(oos_shadow, bool, 0644); #define PT32_LEVEL_SHIFT(level) \ (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS) -#define PT32_LEVEL_MASK(level) \ - (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level)) #define PT32_LVL_OFFSET_MASK(level) \ (PT32_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \ * PT32_LEVEL_BITS))) - 1)) @@ -379,15 +374,15 @@ static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc, static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache, int min) { - struct page *page; + void *page; if (cache->nobjs >= min) return 0; while (cache->nobjs < ARRAY_SIZE(cache->objects)) { - page = alloc_page(GFP_KERNEL); + page = (void *)__get_free_page(GFP_KERNEL); if (!page) return -ENOMEM; - cache->objects[cache->nobjs++] = page_address(page); + cache->objects[cache->nobjs++] = page; } return 0; } @@ -554,13 +549,23 @@ static int host_mapping_level(struct kvm *kvm, gfn_t gfn) return ret; } -static bool mapping_level_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t large_gfn) +static struct kvm_memory_slot * +gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn, + bool no_dirty_log) { struct kvm_memory_slot *slot; - slot = gfn_to_memslot(vcpu->kvm, large_gfn); - if (slot && slot->dirty_bitmap) - return true; - return false; + + slot = gfn_to_memslot(vcpu->kvm, gfn); + if (!slot || slot->flags & KVM_MEMSLOT_INVALID || + (no_dirty_log && slot->dirty_bitmap)) + slot = NULL; + + return slot; +} + +static bool mapping_level_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t large_gfn) +{ + return gfn_to_memslot_dirty_bitmap(vcpu, large_gfn, true); } static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) @@ -1032,9 +1037,9 @@ static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) ASSERT(is_empty_shadow_page(sp->spt)); hlist_del(&sp->hash_link); list_del(&sp->link); - __free_page(virt_to_page(sp->spt)); + free_page((unsigned long)sp->spt); if (!sp->role.direct) - __free_page(virt_to_page(sp->gfns)); + free_page((unsigned long)sp->gfns); kmem_cache_free(mmu_page_header_cache, sp); kvm_mod_used_mmu_pages(kvm, -1); } @@ -1199,6 +1204,13 @@ static void nonpaging_invlpg(struct kvm_vcpu *vcpu, gva_t gva) { } +static void nonpaging_update_pte(struct kvm_vcpu *vcpu, + struct kvm_mmu_page *sp, u64 *spte, + const void *pte, unsigned long mmu_seq) +{ + WARN_ON(1); +} + #define KVM_PAGE_ARRAY_NR 16 struct kvm_mmu_pages { @@ -2150,26 +2162,13 @@ static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) { } -static struct kvm_memory_slot * -pte_prefetch_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn, bool no_dirty_log) -{ - struct kvm_memory_slot *slot; - - slot = gfn_to_memslot(vcpu->kvm, gfn); - if (!slot || slot->flags & KVM_MEMSLOT_INVALID || - (no_dirty_log && slot->dirty_bitmap)) - slot = NULL; - - return slot; -} - static pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, bool no_dirty_log) { struct kvm_memory_slot *slot; unsigned long hva; - slot = pte_prefetch_gfn_to_memslot(vcpu, gfn, no_dirty_log); + slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log); if (!slot) { get_page(bad_page); return page_to_pfn(bad_page); @@ -2190,7 +2189,7 @@ static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, gfn_t gfn; gfn = kvm_mmu_page_get_gfn(sp, start - sp->spt); - if (!pte_prefetch_gfn_to_memslot(vcpu, gfn, access & ACC_WRITE_MASK)) + if (!gfn_to_memslot_dirty_bitmap(vcpu, gfn, access & ACC_WRITE_MASK)) return -1; ret = gfn_to_page_many_atomic(vcpu->kvm, gfn, pages, end - start); @@ -2804,6 +2803,7 @@ static int nonpaging_init_context(struct kvm_vcpu *vcpu, context->prefetch_page = nonpaging_prefetch_page; context->sync_page = nonpaging_sync_page; context->invlpg = nonpaging_invlpg; + context->update_pte = nonpaging_update_pte; context->root_level = 0; context->shadow_root_level = PT32E_ROOT_LEVEL; context->root_hpa = INVALID_PAGE; @@ -2933,6 +2933,7 @@ static int paging64_init_context_common(struct kvm_vcpu *vcpu, context->prefetch_page = paging64_prefetch_page; context->sync_page = paging64_sync_page; context->invlpg = paging64_invlpg; + context->update_pte = paging64_update_pte; context->free = paging_free; context->root_level = level; context->shadow_root_level = level; @@ -2961,6 +2962,7 @@ static int paging32_init_context(struct kvm_vcpu *vcpu, context->prefetch_page = paging32_prefetch_page; context->sync_page = paging32_sync_page; context->invlpg = paging32_invlpg; + context->update_pte = paging32_update_pte; context->root_level = PT32_ROOT_LEVEL; context->shadow_root_level = PT32E_ROOT_LEVEL; context->root_hpa = INVALID_PAGE; @@ -2985,6 +2987,7 @@ static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu) context->prefetch_page = nonpaging_prefetch_page; context->sync_page = nonpaging_sync_page; context->invlpg = nonpaging_invlpg; + context->update_pte = nonpaging_update_pte; context->shadow_root_level = kvm_x86_ops->get_tdp_level(); context->root_hpa = INVALID_PAGE; context->direct_map = true; @@ -3089,8 +3092,6 @@ static int init_kvm_nested_mmu(struct kvm_vcpu *vcpu) static int init_kvm_mmu(struct kvm_vcpu *vcpu) { - vcpu->arch.update_pte.pfn = bad_pfn; - if (mmu_is_nested(vcpu)) return init_kvm_nested_mmu(vcpu); else if (tdp_enabled) @@ -3164,7 +3165,7 @@ static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu, static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, u64 *spte, - const void *new) + const void *new, unsigned long mmu_seq) { if (sp->role.level != PT_PAGE_TABLE_LEVEL) { ++vcpu->kvm->stat.mmu_pde_zapped; @@ -3172,10 +3173,7 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, } ++vcpu->kvm->stat.mmu_pte_updated; - if (!sp->role.cr4_pae) - paging32_update_pte(vcpu, sp, spte, new); - else - paging64_update_pte(vcpu, sp, spte, new); + vcpu->arch.mmu.update_pte(vcpu, sp, spte, new, mmu_seq); } static bool need_remote_flush(u64 old, u64 new) @@ -3210,28 +3208,6 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) return !!(spte && (*spte & shadow_accessed_mask)); } -static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, - u64 gpte) -{ - gfn_t gfn; - pfn_t pfn; - - if (!is_present_gpte(gpte)) - return; - gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; - - vcpu->arch.update_pte.mmu_seq = vcpu->kvm->mmu_notifier_seq; - smp_rmb(); - pfn = gfn_to_pfn(vcpu->kvm, gfn); - - if (is_error_pfn(pfn)) { - kvm_release_pfn_clean(pfn); - return; - } - vcpu->arch.update_pte.gfn = gfn; - vcpu->arch.update_pte.pfn = pfn; -} - static void kvm_mmu_access_page(struct kvm_vcpu *vcpu, gfn_t gfn) { u64 *spte = vcpu->arch.last_pte_updated; @@ -3253,21 +3229,14 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, struct kvm_mmu_page *sp; struct hlist_node *node; LIST_HEAD(invalid_list); - u64 entry, gentry; - u64 *spte; - unsigned offset = offset_in_page(gpa); - unsigned pte_size; - unsigned page_offset; - unsigned misaligned; - unsigned quadrant; - int level; - int flooded = 0; - int npte; - int r; - int invlpg_counter; + unsigned long mmu_seq; + u64 entry, gentry, *spte; + unsigned pte_size, page_offset, misaligned, quadrant, offset; + int level, npte, invlpg_counter, r, flooded = 0; bool remote_flush, local_flush, zap_page; zap_page = remote_flush = local_flush = false; + offset = offset_in_page(gpa); pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); @@ -3275,9 +3244,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, /* * Assume that the pte write on a page table of the same type - * as the current vcpu paging mode. This is nearly always true - * (might be false while changing modes). Note it is verified later - * by update_pte(). + * as the current vcpu paging mode since we update the sptes only + * when they have the same mode. */ if ((is_pae(vcpu) && bytes == 4) || !new) { /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ @@ -3303,15 +3271,17 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, break; } - mmu_guess_page_from_pte_write(vcpu, gpa, gentry); + mmu_seq = vcpu->kvm->mmu_notifier_seq; + smp_rmb(); + spin_lock(&vcpu->kvm->mmu_lock); if (atomic_read(&vcpu->kvm->arch.invlpg_counter) != invlpg_counter) gentry = 0; - kvm_mmu_access_page(vcpu, gfn); kvm_mmu_free_some_pages(vcpu); ++vcpu->kvm->stat.mmu_pte_write; trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); if (guest_initiated) { + kvm_mmu_access_page(vcpu, gfn); if (gfn == vcpu->arch.last_pt_write_gfn && !last_updated_pte_accessed(vcpu)) { ++vcpu->arch.last_pt_write_count; @@ -3375,7 +3345,8 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, if (gentry && !((sp->role.word ^ vcpu->arch.mmu.base_role.word) & mask.word)) - mmu_pte_write_new_pte(vcpu, sp, spte, &gentry); + mmu_pte_write_new_pte(vcpu, sp, spte, &gentry, + mmu_seq); if (!remote_flush && need_remote_flush(entry, *spte)) remote_flush = true; ++spte; @@ -3385,10 +3356,6 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); trace_kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); spin_unlock(&vcpu->kvm->mmu_lock); - if (!is_error_pfn(vcpu->arch.update_pte.pfn)) { - kvm_release_pfn_clean(vcpu->arch.update_pte.pfn); - vcpu->arch.update_pte.pfn = bad_pfn; - } } int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) @@ -3538,14 +3505,23 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) if (!test_bit(slot, sp->slot_bitmap)) continue; - if (sp->role.level != PT_PAGE_TABLE_LEVEL) - continue; - pt = sp->spt; - for (i = 0; i < PT64_ENT_PER_PAGE; ++i) + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + if (!is_shadow_present_pte(pt[i]) || + !is_last_spte(pt[i], sp->role.level)) + continue; + + if (is_large_pte(pt[i])) { + drop_spte(kvm, &pt[i], + shadow_trap_nonpresent_pte); + --kvm->stat.lpages; + continue; + } + /* avoid RMW */ if (is_writable_pte(pt[i])) update_spte(&pt[i], pt[i] & ~PT_WRITABLE_MASK); + } } kvm_flush_remote_tlbs(kvm); } @@ -3583,7 +3559,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) if (nr_to_scan == 0) goto out; - spin_lock(&kvm_lock); + raw_spin_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) { int idx, freed_pages; @@ -3606,7 +3582,7 @@ static int mmu_shrink(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask) if (kvm_freed) list_move_tail(&kvm_freed->vm_list, &vm_list); - spin_unlock(&kvm_lock); + raw_spin_unlock(&kvm_lock); out: return percpu_counter_read_positive(&kvm_total_used_mmu_pages); |