KVM: MMU: shadow support for 1gb pages
[safe/jmp/linux-2.6] / arch / x86 / kvm / mmu.c
index f85d995..1249c12 100644 (file)
@@ -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(&current->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(&current->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;
 }