]> pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - arch/x86/kvm/mmu.c
Fix nfsd truncation of readdir results
[linux-2.6-omap-h63xx.git] / arch / x86 / kvm / mmu.c
index 171bcea1be219e3ed93be697970f30a282dc993c..99c239c5c0ac7becff901a5bbdd399af4ec48293 100644 (file)
@@ -70,6 +70,9 @@ static int dbg = 0;
 module_param(dbg, bool, 0644);
 #endif
 
+static int oos_shadow = 1;
+module_param(oos_shadow, bool, 0644);
+
 #ifndef MMU_DEBUG
 #define ASSERT(x) do { } while (0)
 #else
@@ -135,11 +138,24 @@ module_param(dbg, bool, 0644);
 #define ACC_USER_MASK    PT_USER_MASK
 #define ACC_ALL          (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
 
+#define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
+
 struct kvm_rmap_desc {
        u64 *shadow_ptes[RMAP_EXT];
        struct kvm_rmap_desc *more;
 };
 
+struct kvm_shadow_walk {
+       int (*entry)(struct kvm_shadow_walk *walk, struct kvm_vcpu *vcpu,
+                    u64 addr, u64 *spte, int level);
+};
+
+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);
+
 static struct kmem_cache *pte_chain_cache;
 static struct kmem_cache *rmap_desc_cache;
 static struct kmem_cache *mmu_page_header_cache;
@@ -398,16 +414,19 @@ static int host_largepage_backed(struct kvm *kvm, gfn_t gfn)
 {
        struct vm_area_struct *vma;
        unsigned long addr;
+       int ret = 0;
 
        addr = gfn_to_hva(kvm, gfn);
        if (kvm_is_error_hva(addr))
-               return 0;
+               return ret;
 
+       down_read(&current->mm->mmap_sem);
        vma = find_vma(current->mm, addr);
        if (vma && is_vm_hugetlb_page(vma))
-               return 1;
+               ret = 1;
+       up_read(&current->mm->mmap_sem);
 
-       return 0;
+       return ret;
 }
 
 static int is_largepage_backed(struct kvm_vcpu *vcpu, gfn_t large_gfn)
@@ -642,8 +661,6 @@ static void rmap_write_protect(struct kvm *kvm, u64 gfn)
 
        if (write_protected)
                kvm_flush_remote_tlbs(kvm);
-
-       account_shadowed(kvm, gfn);
 }
 
 static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp)
@@ -852,6 +869,77 @@ static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
        BUG();
 }
 
+
+static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
+                           mmu_parent_walk_fn fn)
+{
+       struct kvm_pte_chain *pte_chain;
+       struct hlist_node *node;
+       struct kvm_mmu_page *parent_sp;
+       int i;
+
+       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);
+               return;
+       }
+       hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
+               for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
+                       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);
+               }
+}
+
+static void kvm_mmu_update_unsync_bitmap(u64 *spte)
+{
+       unsigned int index;
+       struct kvm_mmu_page *sp = page_header(__pa(spte));
+
+       index = spte - sp->spt;
+       __set_bit(index, sp->unsync_child_bitmap);
+       sp->unsync_children = 1;
+}
+
+static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page *sp)
+{
+       struct kvm_pte_chain *pte_chain;
+       struct hlist_node *node;
+       int i;
+
+       if (!sp->parent_pte)
+               return;
+
+       if (!sp->multimapped) {
+               kvm_mmu_update_unsync_bitmap(sp->parent_pte);
+               return;
+       }
+
+       hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
+               for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
+                       if (!pte_chain->parent_ptes[i])
+                               break;
+                       kvm_mmu_update_unsync_bitmap(pte_chain->parent_ptes[i]);
+               }
+}
+
+static int unsync_walk_fn(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+{
+       sp->unsync_children = 1;
+       kvm_mmu_update_parents_unsync(sp);
+       return 1;
+}
+
+static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu *vcpu,
+                                       struct kvm_mmu_page *sp)
+{
+       mmu_parent_walk(vcpu, sp, unsync_walk_fn);
+       kvm_mmu_update_parents_unsync(sp);
+}
+
 static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
                                    struct kvm_mmu_page *sp)
 {
@@ -861,6 +949,58 @@ static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
                sp->spt[i] = shadow_trap_nonpresent_pte;
 }
 
+static int nonpaging_sync_page(struct kvm_vcpu *vcpu,
+                              struct kvm_mmu_page *sp)
+{
+       return 1;
+}
+
+static void nonpaging_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
+{
+}
+
+#define for_each_unsync_children(bitmap, idx)          \
+       for (idx = find_first_bit(bitmap, 512);         \
+            idx < 512;                                 \
+            idx = find_next_bit(bitmap, 512, idx+1))
+
+static int mmu_unsync_walk(struct kvm_mmu_page *sp,
+                          struct kvm_unsync_walk *walker)
+{
+       int i, ret;
+
+       if (!sp->unsync_children)
+               return 0;
+
+       for_each_unsync_children(sp->unsync_child_bitmap, i) {
+               u64 ent = sp->spt[i];
+
+               if (is_shadow_present_pte(ent)) {
+                       struct kvm_mmu_page *child;
+                       child = page_header(ent & PT64_BASE_ADDR_MASK);
+
+                       if (child->unsync_children) {
+                               ret = mmu_unsync_walk(child, walker);
+                               if (ret)
+                                       return ret;
+                               __clear_bit(i, sp->unsync_child_bitmap);
+                       }
+
+                       if (child->unsync) {
+                               ret = walker->entry(child, walker);
+                               __clear_bit(i, sp->unsync_child_bitmap);
+                               if (ret)
+                                       return ret;
+                       }
+               }
+       }
+
+       if (find_first_bit(sp->unsync_child_bitmap, 512) == 512)
+               sp->unsync_children = 0;
+
+       return 0;
+}
+
 static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn)
 {
        unsigned index;
@@ -881,6 +1021,59 @@ static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn)
        return NULL;
 }
 
+static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+{
+       WARN_ON(!sp->unsync);
+       sp->unsync = 0;
+       --kvm->stat.mmu_unsync;
+}
+
+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) {
+               kvm_mmu_zap_page(vcpu->kvm, sp);
+               return 1;
+       }
+
+       rmap_write_protect(vcpu->kvm, sp->gfn);
+       if (vcpu->arch.mmu.sync_page(vcpu, sp)) {
+               kvm_mmu_zap_page(vcpu->kvm, sp);
+               return 1;
+       }
+
+       kvm_mmu_flush_tlb(vcpu);
+       kvm_unlink_unsync_page(vcpu->kvm, sp);
+       return 0;
+}
+
+struct sync_walker {
+       struct kvm_vcpu *vcpu;
+       struct kvm_unsync_walk walker;
+};
+
+static int mmu_sync_fn(struct kvm_mmu_page *sp, struct kvm_unsync_walk *walk)
+{
+       struct sync_walker *sync_walk = container_of(walk, struct sync_walker,
+                                                    walker);
+       struct kvm_vcpu *vcpu = sync_walk->vcpu;
+
+       kvm_sync_page(vcpu, sp);
+       return (need_resched() || spin_needbreak(&vcpu->kvm->mmu_lock));
+}
+
+static void mmu_sync_children(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
+{
+       struct sync_walker walker = {
+               .walker = { .entry = mmu_sync_fn, },
+               .vcpu = vcpu,
+       };
+
+       while (mmu_unsync_walk(sp, &walker.walker))
+               cond_resched_lock(&vcpu->kvm->mmu_lock);
+}
+
 static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
                                             gfn_t gfn,
                                             gva_t gaddr,
@@ -894,7 +1087,7 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
        unsigned quadrant;
        struct hlist_head *bucket;
        struct kvm_mmu_page *sp;
-       struct hlist_node *node;
+       struct hlist_node *node, *tmp;
 
        role.word = 0;
        role.glevels = vcpu->arch.mmu.root_level;
@@ -910,9 +1103,20 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
                 gfn, role.word);
        index = kvm_page_table_hashfn(gfn);
        bucket = &vcpu->kvm->arch.mmu_page_hash[index];
-       hlist_for_each_entry(sp, node, bucket, hash_link)
-               if (sp->gfn == gfn && sp->role.word == role.word) {
+       hlist_for_each_entry_safe(sp, node, tmp, bucket, hash_link)
+               if (sp->gfn == gfn) {
+                       if (sp->unsync)
+                               if (kvm_sync_page(vcpu, sp))
+                                       continue;
+
+                       if (sp->role.word != role.word)
+                               continue;
+
                        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);
+                       }
                        pgprintk("%s: found\n", __func__);
                        return sp;
                }
@@ -924,8 +1128,10 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
        sp->gfn = gfn;
        sp->role = role;
        hlist_add_head(&sp->hash_link, bucket);
-       if (!metaphysical)
+       if (!metaphysical) {
                rmap_write_protect(vcpu->kvm, gfn);
+               account_shadowed(vcpu->kvm, gfn);
+       }
        if (shadow_trap_nonpresent_pte != shadow_notrap_nonpresent_pte)
                vcpu->arch.mmu.prefetch_page(vcpu, sp);
        else
@@ -933,6 +1139,35 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
        return sp;
 }
 
+static int walk_shadow(struct kvm_shadow_walk *walker,
+                      struct kvm_vcpu *vcpu, u64 addr)
+{
+       hpa_t shadow_addr;
+       int level;
+       int r;
+       u64 *sptep;
+       unsigned index;
+
+       shadow_addr = vcpu->arch.mmu.root_hpa;
+       level = vcpu->arch.mmu.shadow_root_level;
+       if (level == PT32E_ROOT_LEVEL) {
+               shadow_addr = vcpu->arch.mmu.pae_root[(addr >> 30) & 3];
+               shadow_addr &= PT64_BASE_ADDR_MASK;
+               --level;
+       }
+
+       while (level >= PT_PAGE_TABLE_LEVEL) {
+               index = SHADOW_PT_INDEX(addr, level);
+               sptep = ((u64 *)__va(shadow_addr)) + index;
+               r = walker->entry(walker, vcpu, addr, sptep, level);
+               if (r)
+                       return r;
+               shadow_addr = *sptep & PT64_BASE_ADDR_MASK;
+               --level;
+       }
+       return 0;
+}
+
 static void kvm_mmu_page_unlink_children(struct kvm *kvm,
                                         struct kvm_mmu_page *sp)
 {
@@ -1002,14 +1237,47 @@ static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp)
        }
 }
 
-static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+struct zap_walker {
+       struct kvm_unsync_walk walker;
+       struct kvm *kvm;
+       int zapped;
+};
+
+static int mmu_zap_fn(struct kvm_mmu_page *sp, struct kvm_unsync_walk *walk)
+{
+       struct zap_walker *zap_walk = container_of(walk, struct zap_walker,
+                                                    walker);
+       kvm_mmu_zap_page(zap_walk->kvm, sp);
+       zap_walk->zapped = 1;
+       return 0;
+}
+
+static int mmu_zap_unsync_children(struct kvm *kvm, struct kvm_mmu_page *sp)
 {
+       struct zap_walker walker = {
+               .walker = { .entry = mmu_zap_fn, },
+               .kvm = kvm,
+               .zapped = 0,
+       };
+
+       if (sp->role.level == PT_PAGE_TABLE_LEVEL)
+               return 0;
+       mmu_unsync_walk(sp, &walker.walker);
+       return walker.zapped;
+}
+
+static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
+{
+       int ret;
        ++kvm->stat.mmu_shadow_zapped;
+       ret = mmu_zap_unsync_children(kvm, sp);
        kvm_mmu_page_unlink_children(kvm, sp);
        kvm_mmu_unlink_parents(kvm, sp);
        kvm_flush_remote_tlbs(kvm);
        if (!sp->role.invalid && !sp->role.metaphysical)
                unaccount_shadowed(kvm, sp->gfn);
+       if (sp->unsync)
+               kvm_unlink_unsync_page(kvm, sp);
        if (!sp->root_count) {
                hlist_del(&sp->hash_link);
                kvm_mmu_free_page(kvm, sp);
@@ -1019,6 +1287,7 @@ static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
                kvm_reload_remote_mmus(kvm);
        }
        kvm_mmu_reset_last_pte_updated(kvm);
+       return ret;
 }
 
 /*
@@ -1071,8 +1340,9 @@ static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn)
                if (sp->gfn == gfn && !sp->role.metaphysical) {
                        pgprintk("%s: gfn %lx role %x\n", __func__, gfn,
                                 sp->role.word);
-                       kvm_mmu_zap_page(kvm, sp);
                        r = 1;
+                       if (kvm_mmu_zap_page(kvm, sp))
+                               n = bucket->first;
                }
        return r;
 }
@@ -1095,6 +1365,20 @@ static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn)
        __set_bit(slot, &sp->slot_bitmap);
 }
 
+static void mmu_convert_notrap(struct kvm_mmu_page *sp)
+{
+       int i;
+       u64 *pt = sp->spt;
+
+       if (shadow_trap_nonpresent_pte == shadow_notrap_nonpresent_pte)
+               return;
+
+       for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
+               if (pt[i] == shadow_notrap_nonpresent_pte)
+                       set_shadow_pte(&pt[i], shadow_trap_nonpresent_pte);
+       }
+}
+
 struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva)
 {
        struct page *page;
@@ -1104,51 +1388,60 @@ struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva)
        if (gpa == UNMAPPED_GVA)
                return NULL;
 
-       down_read(&current->mm->mmap_sem);
        page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);
-       up_read(&current->mm->mmap_sem);
 
        return page;
 }
 
-static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
-                        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)
+static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
 {
-       u64 spte;
-       int was_rmapped = 0;
-       int was_writeble = is_writeble_pte(*shadow_pte);
+       unsigned index;
+       struct hlist_head *bucket;
+       struct kvm_mmu_page *s;
+       struct hlist_node *node, *n;
 
-       pgprintk("%s: spte %llx access %x write_fault %d"
-                " user_fault %d gfn %lx\n",
-                __func__, *shadow_pte, pt_access,
-                write_fault, user_fault, gfn);
+       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 */
+       hlist_for_each_entry_safe(s, node, n, bucket, hash_link) {
+               if (s->gfn != sp->gfn || s->role.metaphysical)
+                       continue;
+               if (s->role.word != sp->role.word)
+                       return 1;
+       }
+       kvm_mmu_mark_parents_unsync(vcpu, sp);
+       ++vcpu->kvm->stat.mmu_unsync;
+       sp->unsync = 1;
+       mmu_convert_notrap(sp);
+       return 0;
+}
 
-       if (is_rmap_pte(*shadow_pte)) {
-               /*
-                * If we overwrite a PTE page pointer with a 2MB PMD, unlink
-                * the parent of the now unreachable PTE.
-                */
-               if (largepage && !is_large_pte(*shadow_pte)) {
-                       struct kvm_mmu_page *child;
-                       u64 pte = *shadow_pte;
+static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
+                                 bool can_unsync)
+{
+       struct kvm_mmu_page *shadow;
 
-                       child = page_header(pte & PT64_BASE_ADDR_MASK);
-                       mmu_page_remove_parent_pte(child, shadow_pte);
-               } else if (pfn != spte_to_pfn(*shadow_pte)) {
-                       pgprintk("hfn old %lx new %lx\n",
-                                spte_to_pfn(*shadow_pte), pfn);
-                       rmap_remove(vcpu->kvm, shadow_pte);
-               } else {
-                       if (largepage)
-                               was_rmapped = is_large_pte(*shadow_pte);
-                       else
-                               was_rmapped = 1;
-               }
+       shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn);
+       if (shadow) {
+               if (shadow->role.level != PT_PAGE_TABLE_LEVEL)
+                       return 1;
+               if (shadow->unsync)
+                       return 0;
+               if (can_unsync && oos_shadow)
+                       return kvm_unsync_page(vcpu, shadow);
+               return 1;
        }
+       return 0;
+}
 
+static int set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
+                   unsigned pte_access, int user_fault,
+                   int write_fault, int dirty, int largepage,
+                   gfn_t gfn, pfn_t pfn, bool speculative,
+                   bool can_unsync)
+{
+       u64 spte;
+       int ret = 0;
        /*
         * We don't set the accessed bit, since we sometimes want to see
         * whether the guest actually used the pte (in order to detect
@@ -1156,7 +1449,7 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
         */
        spte = shadow_base_present_pte | shadow_dirty_mask;
        if (!speculative)
-               pte_access |= PT_ACCESSED_MASK;
+               spte |= shadow_accessed_mask;
        if (!dirty)
                pte_access &= ~ACC_WRITE_MASK;
        if (pte_access & ACC_EXEC_MASK)
@@ -1172,35 +1465,82 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
 
        if ((pte_access & ACC_WRITE_MASK)
            || (write_fault && !is_write_protection(vcpu) && !user_fault)) {
-               struct kvm_mmu_page *shadow;
+
+               if (largepage && has_wrprotected_page(vcpu->kvm, gfn)) {
+                       ret = 1;
+                       spte = shadow_trap_nonpresent_pte;
+                       goto set_pte;
+               }
 
                spte |= PT_WRITABLE_MASK;
 
-               shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn);
-               if (shadow ||
-                  (largepage && has_wrprotected_page(vcpu->kvm, gfn))) {
+               if (mmu_need_write_protect(vcpu, gfn, can_unsync)) {
                        pgprintk("%s: found shadow page for %lx, marking ro\n",
                                 __func__, gfn);
+                       ret = 1;
                        pte_access &= ~ACC_WRITE_MASK;
-                       if (is_writeble_pte(spte)) {
+                       if (is_writeble_pte(spte))
                                spte &= ~PT_WRITABLE_MASK;
-                               kvm_x86_ops->tlb_flush(vcpu);
-                       }
-                       if (write_fault)
-                               *ptwrite = 1;
                }
        }
 
        if (pte_access & ACC_WRITE_MASK)
                mark_page_dirty(vcpu->kvm, gfn);
 
-       pgprintk("%s: setting spte %llx\n", __func__, spte);
-       pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
-                (spte&PT_PAGE_SIZE_MASK)? "2MB" : "4kB",
-                (spte&PT_WRITABLE_MASK)?"RW":"R", gfn, spte, shadow_pte);
+set_pte:
        set_shadow_pte(shadow_pte, spte);
-       if (!was_rmapped && (spte & PT_PAGE_SIZE_MASK)
-           && (spte & PT_PRESENT_MASK))
+       return ret;
+}
+
+static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
+                        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 was_rmapped = 0;
+       int was_writeble = is_writeble_pte(*shadow_pte);
+
+       pgprintk("%s: spte %llx access %x write_fault %d"
+                " user_fault %d gfn %lx\n",
+                __func__, *shadow_pte, pt_access,
+                write_fault, user_fault, gfn);
+
+       if (is_rmap_pte(*shadow_pte)) {
+               /*
+                * If we overwrite a PTE page pointer with a 2MB PMD, unlink
+                * the parent of the now unreachable PTE.
+                */
+               if (largepage && !is_large_pte(*shadow_pte)) {
+                       struct kvm_mmu_page *child;
+                       u64 pte = *shadow_pte;
+
+                       child = page_header(pte & PT64_BASE_ADDR_MASK);
+                       mmu_page_remove_parent_pte(child, shadow_pte);
+               } else if (pfn != spte_to_pfn(*shadow_pte)) {
+                       pgprintk("hfn old %lx new %lx\n",
+                                spte_to_pfn(*shadow_pte), pfn);
+                       rmap_remove(vcpu->kvm, shadow_pte);
+               } else {
+                       if (largepage)
+                               was_rmapped = is_large_pte(*shadow_pte);
+                       else
+                               was_rmapped = 1;
+               }
+       }
+       if (set_spte(vcpu, shadow_pte, pte_access, user_fault, write_fault,
+                     dirty, largepage, gfn, pfn, speculative, true)) {
+               if (write_fault)
+                       *ptwrite = 1;
+               kvm_x86_ops->tlb_flush(vcpu);
+       }
+
+       pgprintk("%s: setting spte %llx\n", __func__, *shadow_pte);
+       pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
+                is_large_pte(*shadow_pte)? "2MB" : "4kB",
+                is_present_pte(*shadow_pte)?"RW":"R", gfn,
+                *shadow_pte, shadow_pte);
+       if (!was_rmapped && is_large_pte(*shadow_pte))
                ++vcpu->kvm->stat.lpages;
 
        page_header_update_slot(vcpu->kvm, shadow_pte, gfn);
@@ -1224,54 +1564,67 @@ 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)
-{
-       hpa_t table_addr = vcpu->arch.mmu.root_hpa;
-       int pt_write = 0;
-
-       for (; ; level--) {
-               u32 index = PT64_INDEX(v, level);
-               u64 *table;
-
-               ASSERT(VALID_PAGE(table_addr));
-               table = __va(table_addr);
+struct direct_shadow_walk {
+       struct kvm_shadow_walk walker;
+       pfn_t pfn;
+       int write;
+       int largepage;
+       int pt_write;
+};
 
-               if (level == 1) {
-                       mmu_set_spte(vcpu, &table[index], ACC_ALL, ACC_ALL,
-                                    0, write, 1, &pt_write, 0, gfn, pfn, false);
-                       return pt_write;
-               }
+static int direct_map_entry(struct kvm_shadow_walk *_walk,
+                           struct kvm_vcpu *vcpu,
+                           u64 addr, u64 *sptep, int level)
+{
+       struct direct_shadow_walk *walk =
+               container_of(_walk, struct direct_shadow_walk, walker);
+       struct kvm_mmu_page *sp;
+       gfn_t pseudo_gfn;
+       gfn_t gfn = addr >> PAGE_SHIFT;
+
+       if (level == PT_PAGE_TABLE_LEVEL
+           || (walk->largepage && level == PT_DIRECTORY_LEVEL)) {
+               mmu_set_spte(vcpu, sptep, ACC_ALL, ACC_ALL,
+                            0, walk->write, 1, &walk->pt_write,
+                            walk->largepage, gfn, walk->pfn, false);
+               ++vcpu->stat.pf_fixed;
+               return 1;
+       }
 
-               if (largepage && level == 2) {
-                       mmu_set_spte(vcpu, &table[index], ACC_ALL, ACC_ALL,
-                                    0, write, 1, &pt_write, 1, gfn, pfn, false);
-                       return pt_write;
+       if (*sptep == shadow_trap_nonpresent_pte) {
+               pseudo_gfn = (addr & PT64_DIR_BASE_ADDR_MASK) >> PAGE_SHIFT;
+               sp = kvm_mmu_get_page(vcpu, pseudo_gfn, (gva_t)addr, level - 1,
+                                     1, ACC_ALL, sptep);
+               if (!sp) {
+                       pgprintk("nonpaging_map: ENOMEM\n");
+                       kvm_release_pfn_clean(walk->pfn);
+                       return -ENOMEM;
                }
 
-               if (table[index] == shadow_trap_nonpresent_pte) {
-                       struct kvm_mmu_page *new_table;
-                       gfn_t pseudo_gfn;
-
-                       pseudo_gfn = (v & PT64_DIR_BASE_ADDR_MASK)
-                               >> PAGE_SHIFT;
-                       new_table = kvm_mmu_get_page(vcpu, pseudo_gfn,
-                                                    v, level - 1,
-                                                    1, ACC_ALL, &table[index]);
-                       if (!new_table) {
-                               pgprintk("nonpaging_map: ENOMEM\n");
-                               kvm_release_pfn_clean(pfn);
-                               return -ENOMEM;
-                       }
-
-                       set_shadow_pte(&table[index],
-                                      __pa(new_table->spt)
-                                      | PT_PRESENT_MASK | PT_WRITABLE_MASK
-                                      | shadow_user_mask | shadow_x_mask);
-               }
-               table_addr = table[index] & PT64_BASE_ADDR_MASK;
+               set_shadow_pte(sptep,
+                              __pa(sp->spt)
+                              | PT_PRESENT_MASK | PT_WRITABLE_MASK
+                              | shadow_user_mask | shadow_x_mask);
        }
+       return 0;
+}
+
+static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
+                       int largepage, gfn_t gfn, pfn_t pfn)
+{
+       int r;
+       struct direct_shadow_walk walker = {
+               .walker = { .entry = direct_map_entry, },
+               .pfn = pfn,
+               .largepage = largepage,
+               .write = write,
+               .pt_write = 0,
+       };
+
+       r = walk_shadow(&walker.walker, vcpu, gfn << PAGE_SHIFT);
+       if (r < 0)
+               return r;
+       return walker.pt_write;
 }
 
 static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
@@ -1281,16 +1634,14 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
        pfn_t pfn;
        unsigned long mmu_seq;
 
-       down_read(&current->mm->mmap_sem);
        if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) {
                gfn &= ~(KVM_PAGES_PER_HPAGE-1);
                largepage = 1;
        }
 
        mmu_seq = vcpu->kvm->mmu_notifier_seq;
-       /* implicit mb(), we'll read before PT lock is unlocked */
+       smp_rmb();
        pfn = gfn_to_pfn(vcpu->kvm, gfn);
-       up_read(&current->mm->mmap_sem);
 
        /* mmio */
        if (is_error_pfn(pfn)) {
@@ -1302,8 +1653,7 @@ 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,
-                        PT32E_ROOT_LEVEL);
+       r = __direct_map(vcpu, v, write, largepage, gfn, pfn);
        spin_unlock(&vcpu->kvm->mmu_lock);
 
 
@@ -1399,6 +1749,37 @@ static void mmu_alloc_roots(struct kvm_vcpu *vcpu)
        vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
 }
 
+static void mmu_sync_roots(struct kvm_vcpu *vcpu)
+{
+       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_sync_children(vcpu, sp);
+               return;
+       }
+       for (i = 0; i < 4; ++i) {
+               hpa_t root = vcpu->arch.mmu.pae_root[i];
+
+               if (root) {
+                       root &= PT64_BASE_ADDR_MASK;
+                       sp = page_header(root);
+                       mmu_sync_children(vcpu, sp);
+               }
+       }
+}
+
+void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
+{
+       spin_lock(&vcpu->kvm->mmu_lock);
+       mmu_sync_roots(vcpu);
+       spin_unlock(&vcpu->kvm->mmu_lock);
+}
+
 static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr)
 {
        return vaddr;
@@ -1440,15 +1821,13 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa,
        if (r)
                return r;
 
-       down_read(&current->mm->mmap_sem);
        if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) {
                gfn &= ~(KVM_PAGES_PER_HPAGE-1);
                largepage = 1;
        }
        mmu_seq = vcpu->kvm->mmu_notifier_seq;
-       /* implicit mb(), we'll read before PT lock is unlocked */
+       smp_rmb();
        pfn = gfn_to_pfn(vcpu->kvm, gfn);
-       up_read(&current->mm->mmap_sem);
        if (is_error_pfn(pfn)) {
                kvm_release_pfn_clean(pfn);
                return 1;
@@ -1458,7 +1837,7 @@ 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, kvm_x86_ops->get_tdp_level());
+                        largepage, gfn, pfn);
        spin_unlock(&vcpu->kvm->mmu_lock);
 
        return r;
@@ -1483,6 +1862,8 @@ static int nonpaging_init_context(struct kvm_vcpu *vcpu)
        context->gva_to_gpa = nonpaging_gva_to_gpa;
        context->free = nonpaging_free;
        context->prefetch_page = nonpaging_prefetch_page;
+       context->sync_page = nonpaging_sync_page;
+       context->invlpg = nonpaging_invlpg;
        context->root_level = 0;
        context->shadow_root_level = PT32E_ROOT_LEVEL;
        context->root_hpa = INVALID_PAGE;
@@ -1530,6 +1911,8 @@ static int paging64_init_context_common(struct kvm_vcpu *vcpu, int level)
        context->page_fault = paging64_page_fault;
        context->gva_to_gpa = paging64_gva_to_gpa;
        context->prefetch_page = paging64_prefetch_page;
+       context->sync_page = paging64_sync_page;
+       context->invlpg = paging64_invlpg;
        context->free = paging_free;
        context->root_level = level;
        context->shadow_root_level = level;
@@ -1551,6 +1934,8 @@ static int paging32_init_context(struct kvm_vcpu *vcpu)
        context->gva_to_gpa = paging32_gva_to_gpa;
        context->free = paging_free;
        context->prefetch_page = paging32_prefetch_page;
+       context->sync_page = paging32_sync_page;
+       context->invlpg = paging32_invlpg;
        context->root_level = PT32_ROOT_LEVEL;
        context->shadow_root_level = PT32E_ROOT_LEVEL;
        context->root_hpa = INVALID_PAGE;
@@ -1570,6 +1955,8 @@ static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
        context->page_fault = tdp_page_fault;
        context->free = nonpaging_free;
        context->prefetch_page = nonpaging_prefetch_page;
+       context->sync_page = nonpaging_sync_page;
+       context->invlpg = nonpaging_invlpg;
        context->shadow_root_level = kvm_x86_ops->get_tdp_level();
        context->root_hpa = INVALID_PAGE;
 
@@ -1641,6 +2028,7 @@ int kvm_mmu_load(struct kvm_vcpu *vcpu)
        spin_lock(&vcpu->kvm->mmu_lock);
        kvm_mmu_free_some_pages(vcpu);
        mmu_alloc_roots(vcpu);
+       mmu_sync_roots(vcpu);
        spin_unlock(&vcpu->kvm->mmu_lock);
        kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa);
        kvm_mmu_flush_tlb(vcpu);
@@ -1761,15 +2149,13 @@ static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
                return;
        gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
 
-       down_read(&current->mm->mmap_sem);
        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;
-       /* implicit mb(), we'll read before PT lock is unlocked */
+       smp_rmb();
        pfn = gfn_to_pfn(vcpu->kvm, gfn);
-       up_read(&current->mm->mmap_sem);
 
        if (is_error_pfn(pfn)) {
                kvm_release_pfn_clean(pfn);
@@ -1849,7 +2235,8 @@ 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);
-                       kvm_mmu_zap_page(vcpu->kvm, sp);
+                       if (kvm_mmu_zap_page(vcpu->kvm, sp))
+                               n = bucket->first;
                        ++vcpu->kvm->stat.mmu_flooded;
                        continue;
                }
@@ -1963,6 +2350,16 @@ out:
 }
 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
 
+void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
+{
+       spin_lock(&vcpu->kvm->mmu_lock);
+       vcpu->arch.mmu.invlpg(vcpu, gva);
+       spin_unlock(&vcpu->kvm->mmu_lock);
+       kvm_mmu_flush_tlb(vcpu);
+       ++vcpu->stat.invlpg;
+}
+EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
+
 void kvm_enable_tdp(void)
 {
        tdp_enabled = true;
@@ -2049,6 +2446,7 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
 {
        struct kvm_mmu_page *sp;
 
+       spin_lock(&kvm->mmu_lock);
        list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) {
                int i;
                u64 *pt;
@@ -2062,6 +2460,8 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
                        if (pt[i] & PT_WRITABLE_MASK)
                                pt[i] &= ~PT_WRITABLE_MASK;
        }
+       kvm_flush_remote_tlbs(kvm);
+       spin_unlock(&kvm->mmu_lock);
 }
 
 void kvm_mmu_zap_all(struct kvm *kvm)
@@ -2070,7 +2470,9 @@ void kvm_mmu_zap_all(struct kvm *kvm)
 
        spin_lock(&kvm->mmu_lock);
        list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link)
-               kvm_mmu_zap_page(kvm, sp);
+               if (kvm_mmu_zap_page(kvm, sp))
+                       node = container_of(kvm->arch.active_mmu_pages.next,
+                                           struct kvm_mmu_page, link);
        spin_unlock(&kvm->mmu_lock);
 
        kvm_flush_remote_tlbs(kvm);