X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=arch%2Fx86%2Fkvm%2Fmmu.c;h=a6f695d76928675008a99f2030b00299856840c4;hp=fd5579cc8abd9187fe71c5c78990d13b0b085e94;hb=69325a122580d3a7b26589e8efdd6663001c3297;hpb=08a3732bf2e68048c9166e929ca2115127a412ab diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index fd5579c..a6f695d 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -18,6 +18,7 @@ */ #include "mmu.h" +#include "x86.h" #include "kvm_cache_regs.h" #include @@ -29,6 +30,8 @@ #include #include #include +#include +#include #include #include @@ -108,6 +111,9 @@ module_param(oos_shadow, bool, 0644); #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)) #define PT32_INDEX(address, level)\ (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1)) @@ -116,23 +122,23 @@ module_param(oos_shadow, bool, 0644); #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1)) #define PT64_DIR_BASE_ADDR_MASK \ (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1)) +#define PT64_LVL_ADDR_MASK(level) \ + (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \ + * PT64_LEVEL_BITS))) - 1)) +#define PT64_LVL_OFFSET_MASK(level) \ + (PT64_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \ + * PT64_LEVEL_BITS))) - 1)) #define PT32_BASE_ADDR_MASK PAGE_MASK #define PT32_DIR_BASE_ADDR_MASK \ (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1)) +#define PT32_LVL_ADDR_MASK(level) \ + (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \ + * PT32_LEVEL_BITS))) - 1)) #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ | PT64_NX_MASK) -#define PFERR_PRESENT_MASK (1U << 0) -#define PFERR_WRITE_MASK (1U << 1) -#define PFERR_USER_MASK (1U << 2) -#define PFERR_RSVD_MASK (1U << 3) -#define PFERR_FETCH_MASK (1U << 4) - -#define PT_DIRECTORY_LEVEL 2 -#define PT_PAGE_TABLE_LEVEL 1 - #define RMAP_EXT 4 #define ACC_EXEC_MASK 1 @@ -140,6 +146,13 @@ module_param(oos_shadow, bool, 0644); #define ACC_USER_MASK PT_USER_MASK #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK) +#include + +#define CREATE_TRACE_POINTS +#include "mmutrace.h" + +#define SPTE_HOST_WRITEABLE (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) + #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level) struct kvm_rmap_desc { @@ -160,12 +173,7 @@ struct kvm_shadow_walk_iterator { shadow_walk_okay(&(_walker)); \ shadow_walk_next(&(_walker))) - -struct kvm_unsync_walk { - int (*entry) (struct kvm_mmu_page *sp, struct kvm_unsync_walk *walk); -}; - -typedef int (*mmu_parent_walk_fn) (struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp); +typedef int (*mmu_parent_walk_fn) (struct kvm_mmu_page *sp); static struct kmem_cache *pte_chain_cache; static struct kmem_cache *rmap_desc_cache; @@ -209,9 +217,9 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, } EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes); -static int is_write_protection(struct kvm_vcpu *vcpu) +static bool is_write_protection(struct kvm_vcpu *vcpu) { - return vcpu->arch.cr0 & X86_CR0_WP; + return kvm_read_cr0_bits(vcpu, X86_CR0_WP); } static int is_cpuid_PSE36(void) @@ -221,7 +229,7 @@ static int is_cpuid_PSE36(void) static int is_nx(struct kvm_vcpu *vcpu) { - return vcpu->arch.shadow_efer & EFER_NX; + return vcpu->arch.efer & EFER_NX; } static int is_shadow_present_pte(u64 pte) @@ -235,7 +243,7 @@ static int is_large_pte(u64 pte) return pte & PT_PAGE_SIZE_MASK; } -static int is_writeble_pte(unsigned long pte) +static int is_writable_pte(unsigned long pte) { return pte & PT_WRITABLE_MASK; } @@ -254,7 +262,7 @@ static int is_last_spte(u64 pte, int level) { if (level == PT_PAGE_TABLE_LEVEL) return 1; - if (level == PT_DIRECTORY_LEVEL && is_large_pte(pte)) + if (is_large_pte(pte)) return 1; return 0; } @@ -313,7 +321,6 @@ static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache, page = alloc_page(GFP_KERNEL); if (!page) return -ENOMEM; - set_page_private(page, 0); cache->objects[cache->nobjs++] = page_address(page); } return 0; @@ -390,37 +397,52 @@ static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd) * Return the pointer to the largepage write count for a given * gfn, handling slots that are not large page aligned. */ -static int *slot_largepage_idx(gfn_t gfn, struct kvm_memory_slot *slot) +static int *slot_largepage_idx(gfn_t gfn, + struct kvm_memory_slot *slot, + int level) { unsigned long idx; - idx = (gfn / KVM_PAGES_PER_HPAGE) - - (slot->base_gfn / KVM_PAGES_PER_HPAGE); - return &slot->lpage_info[idx].write_count; + idx = (gfn / KVM_PAGES_PER_HPAGE(level)) - + (slot->base_gfn / KVM_PAGES_PER_HPAGE(level)); + return &slot->lpage_info[level - 2][idx].write_count; } static void account_shadowed(struct kvm *kvm, gfn_t gfn) { + struct kvm_memory_slot *slot; int *write_count; + int i; gfn = unalias_gfn(kvm, gfn); - write_count = slot_largepage_idx(gfn, - gfn_to_memslot_unaliased(kvm, gfn)); - *write_count += 1; + + slot = gfn_to_memslot_unaliased(kvm, gfn); + for (i = PT_DIRECTORY_LEVEL; + i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { + write_count = slot_largepage_idx(gfn, slot, i); + *write_count += 1; + } } static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn) { + struct kvm_memory_slot *slot; int *write_count; + int i; gfn = unalias_gfn(kvm, gfn); - write_count = slot_largepage_idx(gfn, - gfn_to_memslot_unaliased(kvm, gfn)); - *write_count -= 1; - WARN_ON(*write_count < 0); + slot = gfn_to_memslot_unaliased(kvm, gfn); + for (i = PT_DIRECTORY_LEVEL; + i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { + write_count = slot_largepage_idx(gfn, slot, i); + *write_count -= 1; + WARN_ON(*write_count < 0); + } } -static int has_wrprotected_page(struct kvm *kvm, gfn_t gfn) +static int has_wrprotected_page(struct kvm *kvm, + gfn_t gfn, + int level) { struct kvm_memory_slot *slot; int *largepage_idx; @@ -428,47 +450,53 @@ static int has_wrprotected_page(struct kvm *kvm, gfn_t gfn) gfn = unalias_gfn(kvm, gfn); slot = gfn_to_memslot_unaliased(kvm, gfn); if (slot) { - largepage_idx = slot_largepage_idx(gfn, slot); + largepage_idx = slot_largepage_idx(gfn, slot, level); return *largepage_idx; } return 1; } -static int host_largepage_backed(struct kvm *kvm, gfn_t gfn) +static int host_mapping_level(struct kvm *kvm, gfn_t gfn) { - struct vm_area_struct *vma; - unsigned long addr; - int ret = 0; + unsigned long page_size; + int i, ret = 0; - addr = gfn_to_hva(kvm, gfn); - if (kvm_is_error_hva(addr)) - return ret; + page_size = kvm_host_page_size(kvm, gfn); - down_read(¤t->mm->mmap_sem); - vma = find_vma(current->mm, addr); - if (vma && is_vm_hugetlb_page(vma)) - ret = 1; - up_read(¤t->mm->mmap_sem); + for (i = PT_PAGE_TABLE_LEVEL; + i < (PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES); ++i) { + if (page_size >= KVM_HPAGE_SIZE(i)) + ret = i; + else + break; + } return ret; } -static int is_largepage_backed(struct kvm_vcpu *vcpu, gfn_t large_gfn) +static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) { struct kvm_memory_slot *slot; - - if (has_wrprotected_page(vcpu->kvm, large_gfn)) - return 0; - - if (!host_largepage_backed(vcpu->kvm, large_gfn)) - return 0; + int host_level, level, max_level; slot = gfn_to_memslot(vcpu->kvm, large_gfn); if (slot && slot->dirty_bitmap) - return 0; + return PT_PAGE_TABLE_LEVEL; - return 1; + host_level = host_mapping_level(vcpu->kvm, large_gfn); + + if (host_level == PT_PAGE_TABLE_LEVEL) + return host_level; + + max_level = kvm_x86_ops->get_lpage_level() < host_level ? + kvm_x86_ops->get_lpage_level() : host_level; + + for (level = PT_DIRECTORY_LEVEL; level <= max_level; ++level) + if (has_wrprotected_page(vcpu->kvm, large_gfn, level)) + break; + + return level - 1; } /* @@ -476,19 +504,19 @@ static int is_largepage_backed(struct kvm_vcpu *vcpu, gfn_t large_gfn) * Note: gfn must be unaliased before this function get called */ -static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int lpage) +static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level) { struct kvm_memory_slot *slot; unsigned long idx; slot = gfn_to_memslot(kvm, gfn); - if (!lpage) + if (likely(level == PT_PAGE_TABLE_LEVEL)) return &slot->rmap[gfn - slot->base_gfn]; - idx = (gfn / KVM_PAGES_PER_HPAGE) - - (slot->base_gfn / KVM_PAGES_PER_HPAGE); + idx = (gfn / KVM_PAGES_PER_HPAGE(level)) - + (slot->base_gfn / KVM_PAGES_PER_HPAGE(level)); - return &slot->lpage_info[idx].rmap_pde; + return &slot->lpage_info[level - 2][idx].rmap_pde; } /* @@ -504,7 +532,7 @@ static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int lpage) * the spte was not added. * */ -static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, int lpage) +static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) { struct kvm_mmu_page *sp; struct kvm_rmap_desc *desc; @@ -516,7 +544,7 @@ static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, int lpage) gfn = unalias_gfn(vcpu->kvm, gfn); sp = page_header(__pa(spte)); sp->gfns[spte - sp->spt] = gfn; - rmapp = gfn_to_rmap(vcpu->kvm, gfn, lpage); + rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); if (!*rmapp) { rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte); *rmapp = (unsigned long)spte; @@ -582,11 +610,9 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) pfn = spte_to_pfn(*spte); if (*spte & shadow_accessed_mask) kvm_set_pfn_accessed(pfn); - if (is_writeble_pte(*spte)) - kvm_release_pfn_dirty(pfn); - else - kvm_release_pfn_clean(pfn); - rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], is_large_pte(*spte)); + if (is_writable_pte(*spte)) + kvm_set_pfn_dirty(pfn); + rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], sp->role.level); if (!*rmapp) { printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte); BUG(); @@ -613,6 +639,7 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) prev_desc = desc; desc = desc->more; } + pr_err("rmap_remove: %p %llx many->many\n", spte, *spte); BUG(); } } @@ -620,7 +647,6 @@ static void rmap_remove(struct kvm *kvm, u64 *spte) static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) { struct kvm_rmap_desc *desc; - struct kvm_rmap_desc *prev_desc; u64 *prev_spte; int i; @@ -632,7 +658,6 @@ static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) return NULL; } desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); - prev_desc = NULL; prev_spte = NULL; while (desc) { for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) { @@ -649,17 +674,17 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) { unsigned long *rmapp; u64 *spte; - int write_protected = 0; + int i, write_protected = 0; gfn = unalias_gfn(kvm, gfn); - rmapp = gfn_to_rmap(kvm, gfn, 0); + rmapp = gfn_to_rmap(kvm, gfn, PT_PAGE_TABLE_LEVEL); spte = rmap_next(kvm, rmapp, NULL); while (spte) { BUG_ON(!spte); BUG_ON(!(*spte & PT_PRESENT_MASK)); rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); - if (is_writeble_pte(*spte)) { + if (is_writable_pte(*spte)) { __set_spte(spte, *spte & ~PT_WRITABLE_MASK); write_protected = 1; } @@ -674,27 +699,31 @@ static int rmap_write_protect(struct kvm *kvm, u64 gfn) } /* check for huge page mappings */ - rmapp = gfn_to_rmap(kvm, gfn, 1); - spte = rmap_next(kvm, rmapp, NULL); - while (spte) { - BUG_ON(!spte); - BUG_ON(!(*spte & PT_PRESENT_MASK)); - BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)); - pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn); - if (is_writeble_pte(*spte)) { - rmap_remove(kvm, spte); - --kvm->stat.lpages; - __set_spte(spte, shadow_trap_nonpresent_pte); - spte = NULL; - write_protected = 1; + for (i = PT_DIRECTORY_LEVEL; + i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { + rmapp = gfn_to_rmap(kvm, gfn, i); + spte = rmap_next(kvm, rmapp, NULL); + while (spte) { + BUG_ON(!spte); + BUG_ON(!(*spte & PT_PRESENT_MASK)); + BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)); + pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn); + if (is_writable_pte(*spte)) { + rmap_remove(kvm, spte); + --kvm->stat.lpages; + __set_spte(spte, shadow_trap_nonpresent_pte); + spte = NULL; + write_protected = 1; + } + spte = rmap_next(kvm, rmapp, spte); } - spte = rmap_next(kvm, rmapp, spte); } return write_protected; } -static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) { u64 *spte; int need_tlb_flush = 0; @@ -709,33 +738,75 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) return need_tlb_flush; } +static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) +{ + int need_flush = 0; + u64 *spte, new_spte; + pte_t *ptep = (pte_t *)data; + pfn_t new_pfn; + + WARN_ON(pte_huge(*ptep)); + new_pfn = pte_pfn(*ptep); + spte = rmap_next(kvm, rmapp, NULL); + while (spte) { + BUG_ON(!is_shadow_present_pte(*spte)); + rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", spte, *spte); + need_flush = 1; + if (pte_write(*ptep)) { + rmap_remove(kvm, spte); + __set_spte(spte, shadow_trap_nonpresent_pte); + spte = rmap_next(kvm, rmapp, NULL); + } else { + new_spte = *spte &~ (PT64_BASE_ADDR_MASK); + new_spte |= (u64)new_pfn << PAGE_SHIFT; + + new_spte &= ~PT_WRITABLE_MASK; + new_spte &= ~SPTE_HOST_WRITEABLE; + if (is_writable_pte(*spte)) + kvm_set_pfn_dirty(spte_to_pfn(*spte)); + __set_spte(spte, new_spte); + spte = rmap_next(kvm, rmapp, spte); + } + } + if (need_flush) + kvm_flush_remote_tlbs(kvm); + + return 0; +} + static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, - int (*handler)(struct kvm *kvm, unsigned long *rmapp)) + unsigned long data, + int (*handler)(struct kvm *kvm, unsigned long *rmapp, + unsigned long data)) { - int i; + int i, j; + int ret; int retval = 0; + struct kvm_memslots *slots; - /* - * If mmap_sem isn't taken, we can look the memslots with only - * the mmu_lock by skipping over the slots with userspace_addr == 0. - */ - for (i = 0; i < kvm->nmemslots; i++) { - struct kvm_memory_slot *memslot = &kvm->memslots[i]; + slots = kvm_memslots(kvm); + + for (i = 0; i < slots->nmemslots; i++) { + struct kvm_memory_slot *memslot = &slots->memslots[i]; unsigned long start = memslot->userspace_addr; unsigned long end; - /* mmu_lock protects userspace_addr */ - if (!start) - continue; - end = start + (memslot->npages << PAGE_SHIFT); if (hva >= start && hva < end) { gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT; - retval |= handler(kvm, &memslot->rmap[gfn_offset]); - retval |= handler(kvm, - &memslot->lpage_info[ - gfn_offset / - KVM_PAGES_PER_HPAGE].rmap_pde); + + ret = handler(kvm, &memslot->rmap[gfn_offset], data); + + for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) { + int idx = gfn_offset; + idx /= KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL + j); + ret |= handler(kvm, + &memslot->lpage_info[j][idx].rmap_pde, + data); + } + trace_kvm_age_page(hva, memslot, ret); + retval |= ret; } } @@ -744,17 +815,29 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_unmap_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp); +} + +void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) +{ + kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); } -static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp) +static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, + unsigned long data) { u64 *spte; int young = 0; - /* always return old for EPT */ + /* + * Emulate the accessed bit for EPT, by checking if this page has + * an EPT mapping, and clearing it if it does. On the next access, + * a new EPT mapping will be established. + * This has some overhead, but not as much as the cost of swapping + * out actively used pages or breaking up actively used hugepages. + */ if (!shadow_accessed_mask) - return 0; + return kvm_unmap_rmapp(kvm, rmapp, data); spte = rmap_next(kvm, rmapp, NULL); while (spte) { @@ -773,20 +856,23 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp) #define RMAP_RECYCLE_THRESHOLD 1000 -static void rmap_recycle(struct kvm_vcpu *vcpu, gfn_t gfn, int lpage) +static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) { unsigned long *rmapp; + struct kvm_mmu_page *sp; + + sp = page_header(__pa(spte)); gfn = unalias_gfn(vcpu->kvm, gfn); - rmapp = gfn_to_rmap(vcpu->kvm, gfn, lpage); + rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); - kvm_unmap_rmapp(vcpu->kvm, rmapp); + kvm_unmap_rmapp(vcpu->kvm, rmapp, 0); kvm_flush_remote_tlbs(vcpu->kvm); } int kvm_age_hva(struct kvm *kvm, unsigned long hva) { - return kvm_handle_hva(kvm, hva, kvm_age_rmapp); + return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp); } #ifdef MMU_DEBUG @@ -830,7 +916,6 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); set_page_private(virt_to_page(sp->spt), (unsigned long)sp); list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); - INIT_LIST_HEAD(&sp->oos_link); bitmap_zero(sp->slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS); sp->multimapped = 0; sp->parent_pte = parent_pte; @@ -914,8 +999,7 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, } -static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, - mmu_parent_walk_fn fn) +static void mmu_parent_walk(struct kvm_mmu_page *sp, mmu_parent_walk_fn fn) { struct kvm_pte_chain *pte_chain; struct hlist_node *node; @@ -924,8 +1008,8 @@ static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (!sp->multimapped && sp->parent_pte) { parent_sp = page_header(__pa(sp->parent_pte)); - fn(vcpu, parent_sp); - mmu_parent_walk(vcpu, parent_sp, fn); + fn(parent_sp); + mmu_parent_walk(parent_sp, fn); return; } hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) @@ -933,8 +1017,8 @@ static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (!pte_chain->parent_ptes[i]) break; parent_sp = page_header(__pa(pte_chain->parent_ptes[i])); - fn(vcpu, parent_sp); - mmu_parent_walk(vcpu, parent_sp, fn); + fn(parent_sp); + mmu_parent_walk(parent_sp, fn); } } @@ -971,16 +1055,15 @@ static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page *sp) } } -static int unsync_walk_fn(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) +static int unsync_walk_fn(struct kvm_mmu_page *sp) { kvm_mmu_update_parents_unsync(sp); return 1; } -static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu *vcpu, - struct kvm_mmu_page *sp) +static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page *sp) { - mmu_parent_walk(vcpu, sp, unsync_walk_fn); + mmu_parent_walk(sp, unsync_walk_fn); kvm_mmu_update_parents_unsync(sp); } @@ -1106,6 +1189,7 @@ static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn) static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp) { WARN_ON(!sp->unsync); + trace_kvm_mmu_sync_page(sp); sp->unsync = 0; --kvm->stat.mmu_unsync; } @@ -1114,7 +1198,7 @@ static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp); static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) { - if (sp->role.glevels != vcpu->arch.mmu.root_level) { + if (sp->role.cr4_pae != !!is_pae(vcpu)) { kvm_mmu_zap_page(vcpu->kvm, sp); return 1; } @@ -1235,14 +1319,14 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, role = vcpu->arch.mmu.base_role; role.level = level; role.direct = direct; + if (role.direct) + role.cr4_pae = 0; role.access = access; if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) { quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1; role.quadrant = quadrant; } - pgprintk("%s: looking gfn %lx role %x\n", __func__, - gfn, role.word); index = kvm_page_table_hashfn(gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; hlist_for_each_entry_safe(sp, node, tmp, bucket, hash_link) @@ -1257,16 +1341,15 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, mmu_page_add_parent_pte(vcpu, sp, parent_pte); if (sp->unsync_children) { set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests); - kvm_mmu_mark_parents_unsync(vcpu, sp); + kvm_mmu_mark_parents_unsync(sp); } - pgprintk("%s: found\n", __func__); + trace_kvm_mmu_get_page(sp, false); return sp; } ++vcpu->kvm->stat.mmu_cache_miss; sp = kvm_mmu_alloc_page(vcpu, parent_pte); if (!sp) return sp; - pgprintk("%s: adding gfn %lx role %x\n", __func__, gfn, role.word); sp->gfn = gfn; sp->role = role; hlist_add_head(&sp->hash_link, bucket); @@ -1279,6 +1362,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, vcpu->arch.mmu.prefetch_page(vcpu, sp); else nonpaging_prefetch_page(vcpu, sp); + trace_kvm_mmu_get_page(sp, true); return sp; } @@ -1302,6 +1386,11 @@ static bool shadow_walk_okay(struct kvm_shadow_walk_iterator *iterator) { if (iterator->level < PT_PAGE_TABLE_LEVEL) return false; + + if (iterator->level == PT_PAGE_TABLE_LEVEL) + if (is_large_pte(*iterator->sptep)) + return false; + iterator->index = SHADOW_PT_INDEX(iterator->addr, iterator->level); iterator->sptep = ((u64 *)__va(iterator->shadow_addr)) + iterator->index; return true; @@ -1391,8 +1480,8 @@ static int mmu_zap_unsync_children(struct kvm *kvm, for_each_sp(pages, sp, parents, i) { kvm_mmu_zap_page(kvm, sp); mmu_pages_clear_parents(&parents); + zapped++; } - zapped += pages.nr; kvm_mmu_pages_init(parent, &parents, &pages); } @@ -1402,6 +1491,8 @@ static int mmu_zap_unsync_children(struct kvm *kvm, static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp) { int ret; + + trace_kvm_mmu_zap_page(sp); ++kvm->stat.mmu_shadow_zapped; ret = mmu_zap_unsync_children(kvm, sp); kvm_mmu_page_unlink_children(kvm, sp); @@ -1441,14 +1532,16 @@ void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) */ if (used_pages > kvm_nr_mmu_pages) { - while (used_pages > kvm_nr_mmu_pages) { + while (used_pages > kvm_nr_mmu_pages && + !list_empty(&kvm->arch.active_mmu_pages)) { struct kvm_mmu_page *page; page = container_of(kvm->arch.active_mmu_pages.prev, struct kvm_mmu_page, link); - kvm_mmu_zap_page(kvm, page); + used_pages -= kvm_mmu_zap_page(kvm, page); used_pages--; } + kvm_nr_mmu_pages = used_pages; kvm->arch.n_free_mmu_pages = 0; } else @@ -1470,13 +1563,14 @@ static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) r = 0; index = kvm_page_table_hashfn(gfn); bucket = &kvm->arch.mmu_page_hash[index]; +restart: hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) if (sp->gfn == gfn && !sp->role.direct) { pgprintk("%s: gfn %lx role %x\n", __func__, gfn, sp->role.word); r = 1; if (kvm_mmu_zap_page(kvm, sp)) - n = bucket->first; + goto restart; } return r; } @@ -1490,19 +1584,21 @@ static void mmu_unshadow(struct kvm *kvm, gfn_t gfn) index = kvm_page_table_hashfn(gfn); bucket = &kvm->arch.mmu_page_hash[index]; +restart: hlist_for_each_entry_safe(sp, node, nn, bucket, hash_link) { if (sp->gfn == gfn && !sp->role.direct && !sp->role.invalid) { pgprintk("%s: zap %lx %x\n", __func__, gfn, sp->role.word); - kvm_mmu_zap_page(kvm, sp); + if (kvm_mmu_zap_page(kvm, sp)) + goto restart; } } } static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn) { - int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn)); + int slot = memslot_id(kvm, gfn); struct kvm_mmu_page *sp = page_header(__pa(pte)); __set_bit(slot, sp->slot_bitmap); @@ -1522,20 +1618,6 @@ static void mmu_convert_notrap(struct kvm_mmu_page *sp) } } -struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva) -{ - struct page *page; - - gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); - - if (gpa == UNMAPPED_GVA) - return NULL; - - page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); - - return page; -} - /* * The function is based on mtrr_type_lookup() in * arch/x86/kernel/cpu/mtrr/generic.c @@ -1657,10 +1739,11 @@ static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) if (s->role.word != sp->role.word) return 1; } + trace_kvm_mmu_unsync_page(sp); ++vcpu->kvm->stat.mmu_unsync; sp->unsync = 1; - kvm_mmu_mark_parents_unsync(vcpu, sp); + kvm_mmu_mark_parents_unsync(sp); mmu_convert_notrap(sp); return 0; @@ -1686,9 +1769,9 @@ static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn, static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned pte_access, int user_fault, - int write_fault, int dirty, int largepage, + int write_fault, int dirty, int level, gfn_t gfn, pfn_t pfn, bool speculative, - bool can_unsync) + bool can_unsync, bool reset_host_protection) { u64 spte; int ret = 0; @@ -1709,18 +1792,22 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, spte |= shadow_nx_mask; if (pte_access & ACC_USER_MASK) spte |= shadow_user_mask; - if (largepage) + if (level > PT_PAGE_TABLE_LEVEL) spte |= PT_PAGE_SIZE_MASK; if (tdp_enabled) spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn, kvm_is_mmio_pfn(pfn)); + if (reset_host_protection) + spte |= SPTE_HOST_WRITEABLE; + spte |= (u64)pfn << PAGE_SHIFT; if ((pte_access & ACC_WRITE_MASK) || (write_fault && !is_write_protection(vcpu) && !user_fault)) { - if (largepage && has_wrprotected_page(vcpu->kvm, gfn)) { + if (level > PT_PAGE_TABLE_LEVEL && + has_wrprotected_page(vcpu->kvm, gfn, level)) { ret = 1; spte = shadow_trap_nonpresent_pte; goto set_pte; @@ -1728,13 +1815,16 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, spte |= PT_WRITABLE_MASK; + if (!tdp_enabled && !(pte_access & ACC_WRITE_MASK)) + spte &= ~PT_USER_MASK; + /* * Optimization: for pte sync, if spte was writable the hash * lookup is unnecessary (and expensive). Write protection * is responsibility of mmu_get_page / kvm_sync_page. * Same reasoning can be applied to dirty page accounting. */ - if (!can_unsync && is_writeble_pte(*sptep)) + if (!can_unsync && is_writable_pte(*sptep)) goto set_pte; if (mmu_need_write_protect(vcpu, gfn, can_unsync)) { @@ -1742,7 +1832,7 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, __func__, gfn); ret = 1; pte_access &= ~ACC_WRITE_MASK; - if (is_writeble_pte(spte)) + if (is_writable_pte(spte)) spte &= ~PT_WRITABLE_MASK; } } @@ -1758,11 +1848,12 @@ set_pte: static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, unsigned pt_access, unsigned pte_access, int user_fault, int write_fault, int dirty, - int *ptwrite, int largepage, gfn_t gfn, - pfn_t pfn, bool speculative) + int *ptwrite, int level, gfn_t gfn, + pfn_t pfn, bool speculative, + bool reset_host_protection) { int was_rmapped = 0; - int was_writeble = is_writeble_pte(*sptep); + int was_writable = is_writable_pte(*sptep); int rmap_count; pgprintk("%s: spte %llx access %x write_fault %d" @@ -1775,12 +1866,15 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, * If we overwrite a PTE page pointer with a 2MB PMD, unlink * the parent of the now unreachable PTE. */ - if (largepage && !is_large_pte(*sptep)) { + if (level > PT_PAGE_TABLE_LEVEL && + !is_large_pte(*sptep)) { struct kvm_mmu_page *child; u64 pte = *sptep; child = page_header(pte & PT64_BASE_ADDR_MASK); mmu_page_remove_parent_pte(child, sptep); + __set_spte(sptep, shadow_trap_nonpresent_pte); + kvm_flush_remote_tlbs(vcpu->kvm); } else if (pfn != spte_to_pfn(*sptep)) { pgprintk("hfn old %lx new %lx\n", spte_to_pfn(*sptep), pfn); @@ -1788,8 +1882,10 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, } else was_rmapped = 1; } + if (set_spte(vcpu, sptep, pte_access, user_fault, write_fault, - dirty, largepage, gfn, pfn, speculative, true)) { + dirty, level, gfn, pfn, speculative, true, + reset_host_protection)) { if (write_fault) *ptwrite = 1; kvm_x86_ops->tlb_flush(vcpu); @@ -1798,20 +1894,19 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, pgprintk("%s: setting spte %llx\n", __func__, *sptep); pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n", is_large_pte(*sptep)? "2MB" : "4kB", - is_present_pte(*sptep)?"RW":"R", gfn, - *shadow_pte, sptep); + *sptep & PT_PRESENT_MASK ?"RW":"R", gfn, + *sptep, sptep); if (!was_rmapped && is_large_pte(*sptep)) ++vcpu->kvm->stat.lpages; page_header_update_slot(vcpu->kvm, sptep, gfn); if (!was_rmapped) { - rmap_count = rmap_add(vcpu, sptep, gfn, largepage); - if (!is_rmap_spte(*sptep)) - kvm_release_pfn_clean(pfn); + rmap_count = rmap_add(vcpu, sptep, gfn); + kvm_release_pfn_clean(pfn); if (rmap_count > RMAP_RECYCLE_THRESHOLD) - rmap_recycle(vcpu, gfn, largepage); + rmap_recycle(vcpu, sptep, gfn); } else { - if (was_writeble) + if (was_writable) kvm_release_pfn_dirty(pfn); else kvm_release_pfn_clean(pfn); @@ -1827,7 +1922,7 @@ static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) } static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, - int largepage, gfn_t gfn, pfn_t pfn) + int level, gfn_t gfn, pfn_t pfn) { struct kvm_shadow_walk_iterator iterator; struct kvm_mmu_page *sp; @@ -1835,11 +1930,10 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, gfn_t pseudo_gfn; for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { - if (iterator.level == PT_PAGE_TABLE_LEVEL - || (largepage && iterator.level == PT_DIRECTORY_LEVEL)) { + if (iterator.level == level) { mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, ACC_ALL, 0, write, 1, &pt_write, - largepage, gfn, pfn, false); + level, gfn, pfn, false, true); ++vcpu->stat.pf_fixed; break; } @@ -1867,14 +1961,20 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) { int r; - int largepage = 0; + int level; pfn_t pfn; unsigned long mmu_seq; - if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) { - gfn &= ~(KVM_PAGES_PER_HPAGE-1); - largepage = 1; - } + level = mapping_level(vcpu, gfn); + + /* + * This path builds a PAE pagetable - so we can map 2mb pages at + * maximum. Therefore check if the level is larger than that. + */ + if (level > PT_DIRECTORY_LEVEL) + level = PT_DIRECTORY_LEVEL; + + gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); @@ -1890,7 +1990,7 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) if (mmu_notifier_retry(vcpu, mmu_seq)) goto out_unlock; kvm_mmu_free_some_pages(vcpu); - r = __direct_map(vcpu, v, write, largepage, gfn, pfn); + r = __direct_map(vcpu, v, write, level, gfn, pfn); spin_unlock(&vcpu->kvm->mmu_lock); @@ -1964,21 +2064,23 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) hpa_t root = vcpu->arch.mmu.root_hpa; ASSERT(!VALID_PAGE(root)); - if (tdp_enabled) - direct = 1; if (mmu_check_root(vcpu, root_gfn)) return 1; + if (tdp_enabled) { + direct = 1; + root_gfn = 0; + } + spin_lock(&vcpu->kvm->mmu_lock); sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, direct, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); vcpu->arch.mmu.root_hpa = root; return 0; } direct = !is_paging(vcpu); - if (tdp_enabled) - direct = 1; for (i = 0; i < 4; ++i) { hpa_t root = vcpu->arch.mmu.pae_root[i]; @@ -1994,11 +2096,18 @@ static int mmu_alloc_roots(struct kvm_vcpu *vcpu) root_gfn = 0; if (mmu_check_root(vcpu, root_gfn)) return 1; + if (tdp_enabled) { + direct = 1; + root_gfn = i << 30; + } + spin_lock(&vcpu->kvm->mmu_lock); sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, PT32_ROOT_LEVEL, direct, ACC_ALL, NULL); root = __pa(sp->spt); ++sp->root_count; + spin_unlock(&vcpu->kvm->mmu_lock); + vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; } vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); @@ -2036,8 +2145,11 @@ void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) spin_unlock(&vcpu->kvm->mmu_lock); } -static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr) +static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr, + u32 access, u32 *error) { + if (error) + *error = 0; return vaddr; } @@ -2066,7 +2178,7 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, { pfn_t pfn; int r; - int largepage = 0; + int level; gfn_t gfn = gpa >> PAGE_SHIFT; unsigned long mmu_seq; @@ -2077,10 +2189,10 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, if (r) return r; - if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) { - gfn &= ~(KVM_PAGES_PER_HPAGE-1); - largepage = 1; - } + level = mapping_level(vcpu, gfn); + + gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); + mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); pfn = gfn_to_pfn(vcpu->kvm, gfn); @@ -2093,7 +2205,7 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, goto out_unlock; kvm_mmu_free_some_pages(vcpu); r = __direct_map(vcpu, gpa, error_code & PFERR_WRITE_MASK, - largepage, gfn, pfn); + level, gfn, pfn); spin_unlock(&vcpu->kvm->mmu_lock); return r; @@ -2179,13 +2291,19 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) /* no rsvd bits for 2 level 4K page table entries */ context->rsvd_bits_mask[0][1] = 0; context->rsvd_bits_mask[0][0] = 0; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; + + if (!is_pse(vcpu)) { + context->rsvd_bits_mask[1][1] = 0; + break; + } + if (is_cpuid_PSE36()) /* 36bits PSE 4MB page */ context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21); else /* 32 bits PSE 4MB page */ context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21); - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; break; case PT32E_ROOT_LEVEL: context->rsvd_bits_mask[0][2] = @@ -2198,7 +2316,7 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) context->rsvd_bits_mask[1][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 62) | rsvd_bits(13, 20); /* large page */ - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; break; case PT64_ROOT_LEVEL: context->rsvd_bits_mask[0][3] = exb_bit_rsvd | @@ -2210,11 +2328,13 @@ static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level) context->rsvd_bits_mask[0][0] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51); context->rsvd_bits_mask[1][3] = context->rsvd_bits_mask[0][3]; - context->rsvd_bits_mask[1][2] = context->rsvd_bits_mask[0][2]; + context->rsvd_bits_mask[1][2] = exb_bit_rsvd | + rsvd_bits(maxphyaddr, 51) | + rsvd_bits(13, 29); context->rsvd_bits_mask[1][1] = exb_bit_rsvd | rsvd_bits(maxphyaddr, 51) | rsvd_bits(13, 20); /* large page */ - context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0]; + context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; break; } } @@ -2316,7 +2436,8 @@ static int init_kvm_softmmu(struct kvm_vcpu *vcpu) else r = paging32_init_context(vcpu); - vcpu->arch.mmu.base_role.glevels = vcpu->arch.mmu.root_level; + vcpu->arch.mmu.base_role.cr4_pae = !!is_pae(vcpu); + vcpu->arch.mmu.base_role.cr0_wp = is_write_protection(vcpu); return r; } @@ -2356,13 +2477,15 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu) goto out; spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); + spin_unlock(&vcpu->kvm->mmu_lock); r = mmu_alloc_roots(vcpu); + spin_lock(&vcpu->kvm->mmu_lock); mmu_sync_roots(vcpu); spin_unlock(&vcpu->kvm->mmu_lock); if (r) goto out; + /* set_cr3() should ensure TLB has been flushed */ kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa); - kvm_mmu_flush_tlb(vcpu); out: return r; } @@ -2400,15 +2523,12 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, const void *new) { if (sp->role.level != PT_PAGE_TABLE_LEVEL) { - if (!vcpu->arch.update_pte.largepage || - sp->role.glevels == PT32_ROOT_LEVEL) { - ++vcpu->kvm->stat.mmu_pde_zapped; - return; - } + ++vcpu->kvm->stat.mmu_pde_zapped; + return; } ++vcpu->kvm->stat.mmu_pte_updated; - if (sp->role.glevels == PT32_ROOT_LEVEL) + if (!sp->role.cr4_pae) paging32_update_pte(vcpu, sp, spte, new); else paging64_update_pte(vcpu, sp, spte, new); @@ -2443,46 +2563,15 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) } static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, - const u8 *new, int bytes) + u64 gpte) { gfn_t gfn; - int r; - u64 gpte = 0; pfn_t pfn; - vcpu->arch.update_pte.largepage = 0; - - if (bytes != 4 && bytes != 8) - return; - - /* - * 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(). - */ - if (is_pae(vcpu)) { - /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ - if ((bytes == 4) && (gpa % 4 == 0)) { - r = kvm_read_guest(vcpu->kvm, gpa & ~(u64)7, &gpte, 8); - if (r) - return; - memcpy((void *)&gpte + (gpa % 8), new, 4); - } else if ((bytes == 8) && (gpa % 8 == 0)) { - memcpy((void *)&gpte, new, 8); - } - } else { - if ((bytes == 4) && (gpa % 4 == 0)) - memcpy((void *)&gpte, new, 4); - } if (!is_present_gpte(gpte)) return; gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; - if (is_large_pte(gpte) && is_largepage_backed(vcpu, gfn)) { - gfn &= ~(KVM_PAGES_PER_HPAGE-1); - vcpu->arch.update_pte.largepage = 1; - } vcpu->arch.update_pte.mmu_seq = vcpu->kvm->mmu_notifier_seq; smp_rmb(); pfn = gfn_to_pfn(vcpu->kvm, gfn); @@ -2527,10 +2616,46 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, int flooded = 0; int npte; int r; + int invlpg_counter; pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); - mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes); + + invlpg_counter = atomic_read(&vcpu->kvm->arch.invlpg_counter); + + /* + * 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(). + */ + if ((is_pae(vcpu) && bytes == 4) || !new) { + /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ + if (is_pae(vcpu)) { + gpa &= ~(gpa_t)7; + bytes = 8; + } + r = kvm_read_guest(vcpu->kvm, gpa, &gentry, min(bytes, 8)); + if (r) + gentry = 0; + new = (const u8 *)&gentry; + } + + switch (bytes) { + case 4: + gentry = *(const u32 *)new; + break; + case 8: + gentry = *(const u64 *)new; + break; + default: + gentry = 0; + break; + } + + mmu_guess_page_from_pte_write(vcpu, gpa, gentry); 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; @@ -2549,10 +2674,12 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, } index = kvm_page_table_hashfn(gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; + +restart: hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) { if (sp->gfn != gfn || sp->role.direct || sp->role.invalid) continue; - pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8; + pte_size = sp->role.cr4_pae ? 8 : 4; misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); misaligned |= bytes < 4; if (misaligned || flooded) { @@ -2569,14 +2696,14 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, pgprintk("misaligned: gpa %llx bytes %d role %x\n", gpa, bytes, sp->role.word); if (kvm_mmu_zap_page(vcpu->kvm, sp)) - n = bucket->first; + goto restart; ++vcpu->kvm->stat.mmu_flooded; continue; } page_offset = offset; level = sp->role.level; npte = 1; - if (sp->role.glevels == PT32_ROOT_LEVEL) { + if (!sp->role.cr4_pae) { page_offset <<= 1; /* 32->64 */ /* * A 32-bit pde maps 4MB while the shadow pdes map @@ -2594,20 +2721,11 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, continue; } spte = &sp->spt[page_offset / sizeof(*spte)]; - if ((gpa & (pte_size - 1)) || (bytes < pte_size)) { - gentry = 0; - r = kvm_read_guest_atomic(vcpu->kvm, - gpa & ~(u64)(pte_size - 1), - &gentry, pte_size); - new = (const void *)&gentry; - if (r < 0) - new = NULL; - } while (npte--) { entry = *spte; mmu_pte_write_zap_pte(vcpu, sp, spte); - if (new) - mmu_pte_write_new_pte(vcpu, sp, spte, new); + if (gentry) + mmu_pte_write_new_pte(vcpu, sp, spte, &gentry); mmu_pte_write_flush_tlb(vcpu, entry, *spte); ++spte; } @@ -2625,7 +2743,10 @@ int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) gpa_t gpa; int r; - gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); + if (tdp_enabled) + return 0; + + gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL); spin_lock(&vcpu->kvm->mmu_lock); r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT); @@ -2636,7 +2757,8 @@ EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt); void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) { - while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) { + while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES && + !list_empty(&vcpu->kvm->arch.active_mmu_pages)) { struct kvm_mmu_page *sp; sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev, @@ -2664,7 +2786,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code) if (r) goto out; - er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0); + er = emulate_instruction(vcpu, cr2, error_code, 0); switch (er) { case EMULATE_DONE: @@ -2675,6 +2797,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code) case EMULATE_FAIL: vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR; vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION; + vcpu->run->internal.ndata = 0; return 0; default: BUG(); @@ -2716,12 +2839,6 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) ASSERT(vcpu); - if (vcpu->kvm->arch.n_requested_mmu_pages) - vcpu->kvm->arch.n_free_mmu_pages = - vcpu->kvm->arch.n_requested_mmu_pages; - else - vcpu->kvm->arch.n_free_mmu_pages = - vcpu->kvm->arch.n_alloc_mmu_pages; /* * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. * Therefore we need to allocate shadow page tables in the first @@ -2729,16 +2846,13 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) */ page = alloc_page(GFP_KERNEL | __GFP_DMA32); if (!page) - goto error_1; + return -ENOMEM; + vcpu->arch.mmu.pae_root = page_address(page); for (i = 0; i < 4; ++i) vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; return 0; - -error_1: - free_mmu_pages(vcpu); - return -ENOMEM; } int kvm_mmu_create(struct kvm_vcpu *vcpu) @@ -2791,22 +2905,23 @@ void kvm_mmu_zap_all(struct kvm *kvm) struct kvm_mmu_page *sp, *node; spin_lock(&kvm->mmu_lock); +restart: list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) if (kvm_mmu_zap_page(kvm, sp)) - node = container_of(kvm->arch.active_mmu_pages.next, - struct kvm_mmu_page, link); + goto restart; + spin_unlock(&kvm->mmu_lock); kvm_flush_remote_tlbs(kvm); } -static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm) +static int kvm_mmu_remove_some_alloc_mmu_pages(struct kvm *kvm) { struct kvm_mmu_page *page; page = container_of(kvm->arch.active_mmu_pages.prev, struct kvm_mmu_page, link); - kvm_mmu_zap_page(kvm, page); + return kvm_mmu_zap_page(kvm, page) + 1; } static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) @@ -2818,23 +2933,22 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) spin_lock(&kvm_lock); list_for_each_entry(kvm, &vm_list, vm_list) { - int npages; + int npages, idx, freed_pages; - if (!down_read_trylock(&kvm->slots_lock)) - continue; + idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); npages = kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages; cache_count += npages; if (!kvm_freed && nr_to_scan > 0 && npages > 0) { - kvm_mmu_remove_one_alloc_mmu_page(kvm); - cache_count--; + freed_pages = kvm_mmu_remove_some_alloc_mmu_pages(kvm); + cache_count -= freed_pages; kvm_freed = kvm; } nr_to_scan--; spin_unlock(&kvm->mmu_lock); - up_read(&kvm->slots_lock); + srcu_read_unlock(&kvm->srcu, idx); } if (kvm_freed) list_move_tail(&kvm_freed->vm_list, &vm_list); @@ -2901,9 +3015,12 @@ unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) int i; unsigned int nr_mmu_pages; unsigned int nr_pages = 0; + struct kvm_memslots *slots; - for (i = 0; i < kvm->nmemslots; i++) - nr_pages += kvm->memslots[i].npages; + slots = kvm_memslots(kvm); + + for (i = 0; i < slots->nmemslots; i++) + nr_pages += slots->memslots[i].npages; nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; nr_mmu_pages = max(nr_mmu_pages, @@ -3033,6 +3150,24 @@ out: return r; } +int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) +{ + struct kvm_shadow_walk_iterator iterator; + int nr_sptes = 0; + + spin_lock(&vcpu->kvm->mmu_lock); + for_each_shadow_entry(vcpu, addr, iterator) { + sptes[iterator.level-1] = *iterator.sptep; + nr_sptes++; + if (!is_shadow_present_pte(*iterator.sptep)) + break; + } + spin_unlock(&vcpu->kvm->mmu_lock); + + return nr_sptes; +} +EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy); + #ifdef AUDIT static const char *audit_msg; @@ -3046,8 +3181,7 @@ static gva_t canonicalize(gva_t gva) } -typedef void (*inspect_spte_fn) (struct kvm *kvm, struct kvm_mmu_page *sp, - u64 *sptep); +typedef void (*inspect_spte_fn) (struct kvm *kvm, u64 *sptep); static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, inspect_spte_fn fn) @@ -3058,13 +3192,12 @@ static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, u64 ent = sp->spt[i]; if (is_shadow_present_pte(ent)) { - if (sp->role.level > 1 && !is_large_pte(ent)) { + if (!is_last_spte(ent, sp->role.level)) { struct kvm_mmu_page *child; child = page_header(ent & PT64_BASE_ADDR_MASK); __mmu_spte_walk(kvm, child, fn); - } - if (sp->role.level == 1) - fn(kvm, sp, &sp->spt[i]); + } else + fn(kvm, &sp->spt[i]); } } } @@ -3108,20 +3241,19 @@ static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, continue; va = canonicalize(va); - if (level > 1) { - if (ent == shadow_notrap_nonpresent_pte) - printk(KERN_ERR "audit: (%s) nontrapping pte" - " in nonleaf level: levels %d gva %lx" - " level %d pte %llx\n", audit_msg, - vcpu->arch.mmu.root_level, va, level, ent); - else - audit_mappings_page(vcpu, ent, va, level - 1); - } else { - gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va); + if (is_shadow_present_pte(ent) && !is_last_spte(ent, level)) + audit_mappings_page(vcpu, ent, va, level - 1); + else { + gpa_t gpa = kvm_mmu_gva_to_gpa_read(vcpu, va, NULL); gfn_t gfn = gpa >> PAGE_SHIFT; pfn_t pfn = gfn_to_pfn(vcpu->kvm, gfn); hpa_t hpa = (hpa_t)pfn << PAGE_SHIFT; + if (is_error_pfn(pfn)) { + kvm_release_pfn_clean(pfn); + continue; + } + if (is_shadow_present_pte(ent) && (ent & PT64_BASE_ADDR_MASK) != hpa) printk(KERN_ERR "xx audit error: (%s) levels %d" @@ -3156,11 +3288,15 @@ static void audit_mappings(struct kvm_vcpu *vcpu) static int count_rmaps(struct kvm_vcpu *vcpu) { + struct kvm *kvm = vcpu->kvm; + struct kvm_memslots *slots; int nmaps = 0; - int i, j, k; + int i, j, k, idx; + idx = srcu_read_lock(&kvm->srcu); + slots = kvm_memslots(kvm); for (i = 0; i < KVM_MEMORY_SLOTS; ++i) { - struct kvm_memory_slot *m = &vcpu->kvm->memslots[i]; + struct kvm_memory_slot *m = &slots->memslots[i]; struct kvm_rmap_desc *d; for (j = 0; j < m->npages; ++j) { @@ -3183,10 +3319,11 @@ static int count_rmaps(struct kvm_vcpu *vcpu) } } } + srcu_read_unlock(&kvm->srcu, idx); return nmaps; } -void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep) +void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) { unsigned long *rmapp; struct kvm_mmu_page *rev_sp; @@ -3202,13 +3339,14 @@ void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep) printk(KERN_ERR "%s: no memslot for gfn %ld\n", audit_msg, gfn); printk(KERN_ERR "%s: index %ld of sp (gfn=%lx)\n", - audit_msg, sptep - rev_sp->spt, + audit_msg, (long int)(sptep - rev_sp->spt), rev_sp->gfn); dump_stack(); return; } - rmapp = gfn_to_rmap(kvm, rev_sp->gfns[sptep - rev_sp->spt], 0); + rmapp = gfn_to_rmap(kvm, rev_sp->gfns[sptep - rev_sp->spt], + rev_sp->role.level); if (!*rmapp) { if (!printk_ratelimit()) return; @@ -3243,7 +3381,7 @@ static void check_writable_mappings_rmap(struct kvm_vcpu *vcpu) continue; if (!(ent & PT_WRITABLE_MASK)) continue; - inspect_spte_has_rmap(vcpu->kvm, sp, &pt[i]); + inspect_spte_has_rmap(vcpu->kvm, &pt[i]); } } return; @@ -3260,20 +3398,28 @@ static void audit_write_protection(struct kvm_vcpu *vcpu) struct kvm_mmu_page *sp; struct kvm_memory_slot *slot; unsigned long *rmapp; + u64 *spte; gfn_t gfn; list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { if (sp->role.direct) continue; + if (sp->unsync) + continue; gfn = unalias_gfn(vcpu->kvm, sp->gfn); slot = gfn_to_memslot_unaliased(vcpu->kvm, sp->gfn); rmapp = &slot->rmap[gfn - slot->base_gfn]; - if (*rmapp) - printk(KERN_ERR "%s: (%s) shadow page has writable" - " mappings: gfn %lx role %x\n", + + spte = rmap_next(vcpu->kvm, rmapp, NULL); + while (spte) { + if (*spte & PT_WRITABLE_MASK) + printk(KERN_ERR "%s: (%s) shadow page has " + "writable mappings: gfn %lx role %x\n", __func__, audit_msg, sp->gfn, sp->role.word); + spte = rmap_next(vcpu->kvm, rmapp, spte); + } } } @@ -3285,7 +3431,8 @@ static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) audit_msg = msg; audit_rmap(vcpu); audit_write_protection(vcpu); - audit_mappings(vcpu); + if (strcmp("pre pte write", audit_msg) != 0) + audit_mappings(vcpu); audit_writable_sptes_have_rmaps(vcpu); dbg = olddbg; }