X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fkvm%2Fmmu.c;h=1249c12e1d5c50febda0129ccecbfac20e43217a;hb=7e4e4056f72da51c5dede48515df0ecd20eaf8ca;hp=f85d9953a6205efdbb7438b958d2ef182eac4342;hpb=776e6633363b5616be6fa4493a8b70ef8e2ea04b;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index f85d995..1249c12 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -108,6 +108,9 @@ 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)) @@ -116,10 +119,19 @@ 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) @@ -130,6 +142,7 @@ module_param(oos_shadow, bool, 0644); #define PFERR_RSVD_MASK (1U << 3) #define PFERR_FETCH_MASK (1U << 4) +#define PT_PDPE_LEVEL 3 #define PT_DIRECTORY_LEVEL 2 #define PT_PAGE_TABLE_LEVEL 1 @@ -140,6 +153,9 @@ 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) +#define CREATE_TRACE_POINTS +#include "mmutrace.h" + #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level) struct kvm_rmap_desc { @@ -254,7 +270,7 @@ 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; } @@ -390,37 +406,52 @@ 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); + for (i = PT_DIRECTORY_LEVEL; + i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { + slot = gfn_to_memslot_unaliased(kvm, gfn); + 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 +459,67 @@ 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) { + unsigned long page_size = PAGE_SIZE; struct vm_area_struct *vma; unsigned long addr; - int ret = 0; + int i, ret = 0; addr = gfn_to_hva(kvm, gfn); if (kvm_is_error_hva(addr)) - return ret; + return page_size; down_read(¤t->mm->mmap_sem); vma = find_vma(current->mm, addr); - if (vma && is_vm_hugetlb_page(vma)) - ret = 1; + if (!vma) + goto out; + + page_size = vma_kernel_pagesize(vma); + +out: 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; + int level = PT_PAGE_TABLE_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; + + for (level = PT_DIRECTORY_LEVEL; level <= host_level; ++level) { + + if (has_wrprotected_page(vcpu->kvm, large_gfn, level)) + break; + } + + return level - 1; } /* @@ -476,19 +527,19 @@ 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 +555,7 @@ 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 +567,7 @@ 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; @@ -586,7 +637,7 @@ static void rmap_remove(struct kvm *kvm, u64 *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)); + 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(); @@ -649,10 +700,10 @@ 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) { @@ -674,21 +725,24 @@ 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_writeble_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; @@ -712,7 +766,7 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp) static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, int (*handler)(struct kvm *kvm, unsigned long *rmapp)) { - int i; + int i, j; int retval = 0; /* @@ -731,11 +785,15 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, 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); + + for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) { + int idx = gfn_offset; + idx /= KVM_PAGES_PER_HPAGE(PT_DIRECTORY_LEVEL + j); + retval |= handler(kvm, + &memslot->lpage_info[j][idx].rmap_pde); + } } } @@ -773,12 +831,15 @@ 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_flush_remote_tlbs(vcpu->kvm); @@ -1119,6 +1180,7 @@ static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) return 1; } + trace_kvm_mmu_sync_page(sp); if (rmap_write_protect(vcpu->kvm, sp->gfn)) kvm_flush_remote_tlbs(vcpu->kvm); kvm_unlink_unsync_page(vcpu->kvm, sp); @@ -1241,8 +1303,6 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, 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) @@ -1259,14 +1319,13 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests); kvm_mmu_mark_parents_unsync(vcpu, 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 +1338,7 @@ 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 +1362,11 @@ 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; @@ -1402,6 +1467,8 @@ 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); @@ -1648,6 +1715,7 @@ static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) struct kvm_mmu_page *s; struct hlist_node *node, *n; + trace_kvm_mmu_unsync_page(sp); index = kvm_page_table_hashfn(sp->gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; /* don't unsync if pagetable is shadowed with multiple roles */ @@ -1686,7 +1754,7 @@ 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) { @@ -1709,7 +1777,7 @@ 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, @@ -1720,7 +1788,8 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, 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; @@ -1758,7 +1827,7 @@ 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, + int *ptwrite, int level, gfn_t gfn, pfn_t pfn, bool speculative) { int was_rmapped = 0; @@ -1775,7 +1844,8 @@ 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; @@ -1788,8 +1858,9 @@ 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)) { if (write_fault) *ptwrite = 1; kvm_x86_ops->tlb_flush(vcpu); @@ -1798,18 +1869,18 @@ 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); + rmap_count = rmap_add(vcpu, sptep, gfn); if (!is_rmap_spte(*sptep)) 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) kvm_release_pfn_dirty(pfn); @@ -1827,7 +1898,7 @@ 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 +1906,10 @@ 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); ++vcpu->stat.pf_fixed; break; } @@ -1867,14 +1937,20 @@ 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 +1966,7 @@ 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); @@ -2066,7 +2142,7 @@ 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 +2153,10 @@ 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 +2169,7 @@ 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; @@ -2210,7 +2286,9 @@ 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 */ @@ -2361,8 +2439,8 @@ int kvm_mmu_load(struct kvm_vcpu *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; } @@ -2400,11 +2478,8 @@ 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; @@ -2450,8 +2525,6 @@ static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, u64 gpte = 0; pfn_t pfn; - vcpu->arch.update_pte.largepage = 0; - if (bytes != 4 && bytes != 8) return; @@ -2479,10 +2552,6 @@ static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, 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); @@ -2716,12 +2785,14 @@ static int alloc_mmu_pages(struct kvm_vcpu *vcpu) ASSERT(vcpu); + spin_lock(&vcpu->kvm->mmu_lock); 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; + spin_unlock(&vcpu->kvm->mmu_lock); /* * 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 @@ -3033,6 +3104,24 @@ 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; @@ -3045,6 +3134,54 @@ static gva_t canonicalize(gva_t gva) return gva; } + +typedef void (*inspect_spte_fn) (struct kvm *kvm, struct kvm_mmu_page *sp, + u64 *sptep); + +static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp, + inspect_spte_fn fn) +{ + int i; + + for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { + u64 ent = sp->spt[i]; + + if (is_shadow_present_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); + } else + fn(kvm, sp, &sp->spt[i]); + } + } +} + +static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn) +{ + int i; + struct kvm_mmu_page *sp; + + if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) + return; + if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { + hpa_t root = vcpu->arch.mmu.root_hpa; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + return; + } + for (i = 0; i < 4; ++i) { + hpa_t root = vcpu->arch.mmu.pae_root[i]; + + if (root && VALID_PAGE(root)) { + root &= PT64_BASE_ADDR_MASK; + sp = page_header(root); + __mmu_spte_walk(vcpu->kvm, sp, fn); + } + } + return; +} + static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, gva_t va, int level) { @@ -3059,20 +3196,19 @@ 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 { + if (is_shadow_present_pte(ent) && !is_last_spte(ent, level)) + audit_mappings_page(vcpu, ent, va, level - 1); + else { gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va); 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" @@ -3137,9 +3273,48 @@ static int count_rmaps(struct kvm_vcpu *vcpu) return nmaps; } -static int count_writable_mappings(struct kvm_vcpu *vcpu) +void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep) +{ + unsigned long *rmapp; + struct kvm_mmu_page *rev_sp; + gfn_t gfn; + + if (*sptep & PT_WRITABLE_MASK) { + rev_sp = page_header(__pa(sptep)); + gfn = rev_sp->gfns[sptep - rev_sp->spt]; + + if (!gfn_to_memslot(kvm, gfn)) { + if (!printk_ratelimit()) + return; + 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, + rev_sp->gfn); + dump_stack(); + return; + } + + rmapp = gfn_to_rmap(kvm, rev_sp->gfns[sptep - rev_sp->spt], + is_large_pte(*sptep)); + if (!*rmapp) { + if (!printk_ratelimit()) + return; + printk(KERN_ERR "%s: no rmap for writable spte %llx\n", + audit_msg, *sptep); + dump_stack(); + } + } + +} + +void audit_writable_sptes_have_rmaps(struct kvm_vcpu *vcpu) +{ + mmu_spte_walk(vcpu, inspect_spte_has_rmap); +} + +static void check_writable_mappings_rmap(struct kvm_vcpu *vcpu) { - int nmaps = 0; struct kvm_mmu_page *sp; int i; @@ -3156,20 +3331,16 @@ static int count_writable_mappings(struct kvm_vcpu *vcpu) continue; if (!(ent & PT_WRITABLE_MASK)) continue; - ++nmaps; + inspect_spte_has_rmap(vcpu->kvm, sp, &pt[i]); } } - return nmaps; + return; } static void audit_rmap(struct kvm_vcpu *vcpu) { - int n_rmap = count_rmaps(vcpu); - int n_actual = count_writable_mappings(vcpu); - - if (n_rmap != n_actual) - printk(KERN_ERR "%s: (%s) rmap %d actual %d\n", - __func__, audit_msg, n_rmap, n_actual); + check_writable_mappings_rmap(vcpu); + count_rmaps(vcpu); } static void audit_write_protection(struct kvm_vcpu *vcpu) @@ -3177,20 +3348,28 @@ 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); + } } } @@ -3202,7 +3381,9 @@ 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; }