2 * Kernel-based Virtual Machine driver for Linux
4 * This module enables machines with Intel VT-x extensions to run virtual
5 * machines without emulation or binary translation.
9 * Copyright (C) 2006 Qumranet, Inc.
12 * Yaniv Kamay <yaniv@qumranet.com>
13 * Avi Kivity <avi@qumranet.com>
15 * This work is licensed under the terms of the GNU GPL, version 2. See
16 * the COPYING file in the top-level directory.
21 #include "kvm_cache_regs.h"
23 #include <linux/kvm_host.h>
24 #include <linux/types.h>
25 #include <linux/string.h>
27 #include <linux/highmem.h>
28 #include <linux/module.h>
29 #include <linux/swap.h>
30 #include <linux/hugetlb.h>
31 #include <linux/compiler.h>
34 #include <asm/cmpxchg.h>
39 * When setting this variable to true it enables Two-Dimensional-Paging
40 * where the hardware walks 2 page tables:
41 * 1. the guest-virtual to guest-physical
42 * 2. while doing 1. it walks guest-physical to host-physical
43 * If the hardware supports that we don't need to do shadow paging.
45 bool tdp_enabled = false;
52 static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg);
54 static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {}
59 #define pgprintk(x...) do { if (dbg) printk(x); } while (0)
60 #define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
64 #define pgprintk(x...) do { } while (0)
65 #define rmap_printk(x...) do { } while (0)
69 #if defined(MMU_DEBUG) || defined(AUDIT)
71 module_param(dbg, bool, 0644);
74 static int oos_shadow = 1;
75 module_param(oos_shadow, bool, 0644);
78 #define ASSERT(x) do { } while (0)
82 printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
83 __FILE__, __LINE__, #x); \
87 #define PT_FIRST_AVAIL_BITS_SHIFT 9
88 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
90 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
92 #define PT64_LEVEL_BITS 9
94 #define PT64_LEVEL_SHIFT(level) \
95 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
97 #define PT64_LEVEL_MASK(level) \
98 (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
100 #define PT64_INDEX(address, level)\
101 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
104 #define PT32_LEVEL_BITS 10
106 #define PT32_LEVEL_SHIFT(level) \
107 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
109 #define PT32_LEVEL_MASK(level) \
110 (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
112 #define PT32_INDEX(address, level)\
113 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
116 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
117 #define PT64_DIR_BASE_ADDR_MASK \
118 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
120 #define PT32_BASE_ADDR_MASK PAGE_MASK
121 #define PT32_DIR_BASE_ADDR_MASK \
122 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
124 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
127 #define PFERR_PRESENT_MASK (1U << 0)
128 #define PFERR_WRITE_MASK (1U << 1)
129 #define PFERR_USER_MASK (1U << 2)
130 #define PFERR_RSVD_MASK (1U << 3)
131 #define PFERR_FETCH_MASK (1U << 4)
133 #define PT_DIRECTORY_LEVEL 2
134 #define PT_PAGE_TABLE_LEVEL 1
138 #define ACC_EXEC_MASK 1
139 #define ACC_WRITE_MASK PT_WRITABLE_MASK
140 #define ACC_USER_MASK PT_USER_MASK
141 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
143 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
145 struct kvm_rmap_desc {
146 u64 *sptes[RMAP_EXT];
147 struct kvm_rmap_desc *more;
150 struct kvm_shadow_walk_iterator {
158 #define for_each_shadow_entry(_vcpu, _addr, _walker) \
159 for (shadow_walk_init(&(_walker), _vcpu, _addr); \
160 shadow_walk_okay(&(_walker)); \
161 shadow_walk_next(&(_walker)))
164 struct kvm_unsync_walk {
165 int (*entry) (struct kvm_mmu_page *sp, struct kvm_unsync_walk *walk);
168 typedef int (*mmu_parent_walk_fn) (struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp);
170 static struct kmem_cache *pte_chain_cache;
171 static struct kmem_cache *rmap_desc_cache;
172 static struct kmem_cache *mmu_page_header_cache;
174 static u64 __read_mostly shadow_trap_nonpresent_pte;
175 static u64 __read_mostly shadow_notrap_nonpresent_pte;
176 static u64 __read_mostly shadow_base_present_pte;
177 static u64 __read_mostly shadow_nx_mask;
178 static u64 __read_mostly shadow_x_mask; /* mutual exclusive with nx_mask */
179 static u64 __read_mostly shadow_user_mask;
180 static u64 __read_mostly shadow_accessed_mask;
181 static u64 __read_mostly shadow_dirty_mask;
183 static inline u64 rsvd_bits(int s, int e)
185 return ((1ULL << (e - s + 1)) - 1) << s;
188 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte)
190 shadow_trap_nonpresent_pte = trap_pte;
191 shadow_notrap_nonpresent_pte = notrap_pte;
193 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes);
195 void kvm_mmu_set_base_ptes(u64 base_pte)
197 shadow_base_present_pte = base_pte;
199 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes);
201 void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask,
202 u64 dirty_mask, u64 nx_mask, u64 x_mask)
204 shadow_user_mask = user_mask;
205 shadow_accessed_mask = accessed_mask;
206 shadow_dirty_mask = dirty_mask;
207 shadow_nx_mask = nx_mask;
208 shadow_x_mask = x_mask;
210 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes);
212 static int is_write_protection(struct kvm_vcpu *vcpu)
214 return vcpu->arch.cr0 & X86_CR0_WP;
217 static int is_cpuid_PSE36(void)
222 static int is_nx(struct kvm_vcpu *vcpu)
224 return vcpu->arch.shadow_efer & EFER_NX;
227 static int is_shadow_present_pte(u64 pte)
229 return pte != shadow_trap_nonpresent_pte
230 && pte != shadow_notrap_nonpresent_pte;
233 static int is_large_pte(u64 pte)
235 return pte & PT_PAGE_SIZE_MASK;
238 static int is_writeble_pte(unsigned long pte)
240 return pte & PT_WRITABLE_MASK;
243 static int is_dirty_gpte(unsigned long pte)
245 return pte & PT_DIRTY_MASK;
248 static int is_rmap_spte(u64 pte)
250 return is_shadow_present_pte(pte);
253 static int is_last_spte(u64 pte, int level)
255 if (level == PT_PAGE_TABLE_LEVEL)
257 if (level == PT_DIRECTORY_LEVEL && is_large_pte(pte))
262 static pfn_t spte_to_pfn(u64 pte)
264 return (pte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
267 static gfn_t pse36_gfn_delta(u32 gpte)
269 int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT;
271 return (gpte & PT32_DIR_PSE36_MASK) << shift;
274 static void __set_spte(u64 *sptep, u64 spte)
277 set_64bit((unsigned long *)sptep, spte);
279 set_64bit((unsigned long long *)sptep, spte);
283 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
284 struct kmem_cache *base_cache, int min)
288 if (cache->nobjs >= min)
290 while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
291 obj = kmem_cache_zalloc(base_cache, GFP_KERNEL);
294 cache->objects[cache->nobjs++] = obj;
299 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
302 kfree(mc->objects[--mc->nobjs]);
305 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache,
310 if (cache->nobjs >= min)
312 while (cache->nobjs < ARRAY_SIZE(cache->objects)) {
313 page = alloc_page(GFP_KERNEL);
316 set_page_private(page, 0);
317 cache->objects[cache->nobjs++] = page_address(page);
322 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache *mc)
325 free_page((unsigned long)mc->objects[--mc->nobjs]);
328 static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu)
332 r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_chain_cache,
336 r = mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache,
340 r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8);
343 r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache,
344 mmu_page_header_cache, 4);
349 static void mmu_free_memory_caches(struct kvm_vcpu *vcpu)
351 mmu_free_memory_cache(&vcpu->arch.mmu_pte_chain_cache);
352 mmu_free_memory_cache(&vcpu->arch.mmu_rmap_desc_cache);
353 mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache);
354 mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache);
357 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc,
363 p = mc->objects[--mc->nobjs];
367 static struct kvm_pte_chain *mmu_alloc_pte_chain(struct kvm_vcpu *vcpu)
369 return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_chain_cache,
370 sizeof(struct kvm_pte_chain));
373 static void mmu_free_pte_chain(struct kvm_pte_chain *pc)
378 static struct kvm_rmap_desc *mmu_alloc_rmap_desc(struct kvm_vcpu *vcpu)
380 return mmu_memory_cache_alloc(&vcpu->arch.mmu_rmap_desc_cache,
381 sizeof(struct kvm_rmap_desc));
384 static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd)
390 * Return the pointer to the largepage write count for a given
391 * gfn, handling slots that are not large page aligned.
393 static int *slot_largepage_idx(gfn_t gfn, struct kvm_memory_slot *slot)
397 idx = (gfn / KVM_PAGES_PER_HPAGE) -
398 (slot->base_gfn / KVM_PAGES_PER_HPAGE);
399 return &slot->lpage_info[idx].write_count;
402 static void account_shadowed(struct kvm *kvm, gfn_t gfn)
406 gfn = unalias_gfn(kvm, gfn);
407 write_count = slot_largepage_idx(gfn,
408 gfn_to_memslot_unaliased(kvm, gfn));
412 static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn)
416 gfn = unalias_gfn(kvm, gfn);
417 write_count = slot_largepage_idx(gfn,
418 gfn_to_memslot_unaliased(kvm, gfn));
420 WARN_ON(*write_count < 0);
423 static int has_wrprotected_page(struct kvm *kvm, gfn_t gfn)
425 struct kvm_memory_slot *slot;
428 gfn = unalias_gfn(kvm, gfn);
429 slot = gfn_to_memslot_unaliased(kvm, gfn);
431 largepage_idx = slot_largepage_idx(gfn, slot);
432 return *largepage_idx;
438 static int host_largepage_backed(struct kvm *kvm, gfn_t gfn)
440 struct vm_area_struct *vma;
444 addr = gfn_to_hva(kvm, gfn);
445 if (kvm_is_error_hva(addr))
448 down_read(¤t->mm->mmap_sem);
449 vma = find_vma(current->mm, addr);
450 if (vma && is_vm_hugetlb_page(vma))
452 up_read(¤t->mm->mmap_sem);
457 static int is_largepage_backed(struct kvm_vcpu *vcpu, gfn_t large_gfn)
459 struct kvm_memory_slot *slot;
461 if (has_wrprotected_page(vcpu->kvm, large_gfn))
464 if (!host_largepage_backed(vcpu->kvm, large_gfn))
467 slot = gfn_to_memslot(vcpu->kvm, large_gfn);
468 if (slot && slot->dirty_bitmap)
475 * Take gfn and return the reverse mapping to it.
476 * Note: gfn must be unaliased before this function get called
479 static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int lpage)
481 struct kvm_memory_slot *slot;
484 slot = gfn_to_memslot(kvm, gfn);
486 return &slot->rmap[gfn - slot->base_gfn];
488 idx = (gfn / KVM_PAGES_PER_HPAGE) -
489 (slot->base_gfn / KVM_PAGES_PER_HPAGE);
491 return &slot->lpage_info[idx].rmap_pde;
495 * Reverse mapping data structures:
497 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
498 * that points to page_address(page).
500 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
501 * containing more mappings.
503 * Returns the number of rmap entries before the spte was added or zero if
504 * the spte was not added.
507 static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn, int lpage)
509 struct kvm_mmu_page *sp;
510 struct kvm_rmap_desc *desc;
511 unsigned long *rmapp;
514 if (!is_rmap_spte(*spte))
516 gfn = unalias_gfn(vcpu->kvm, gfn);
517 sp = page_header(__pa(spte));
518 sp->gfns[spte - sp->spt] = gfn;
519 rmapp = gfn_to_rmap(vcpu->kvm, gfn, lpage);
521 rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte);
522 *rmapp = (unsigned long)spte;
523 } else if (!(*rmapp & 1)) {
524 rmap_printk("rmap_add: %p %llx 1->many\n", spte, *spte);
525 desc = mmu_alloc_rmap_desc(vcpu);
526 desc->sptes[0] = (u64 *)*rmapp;
527 desc->sptes[1] = spte;
528 *rmapp = (unsigned long)desc | 1;
530 rmap_printk("rmap_add: %p %llx many->many\n", spte, *spte);
531 desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
532 while (desc->sptes[RMAP_EXT-1] && desc->more) {
536 if (desc->sptes[RMAP_EXT-1]) {
537 desc->more = mmu_alloc_rmap_desc(vcpu);
540 for (i = 0; desc->sptes[i]; ++i)
542 desc->sptes[i] = spte;
547 static void rmap_desc_remove_entry(unsigned long *rmapp,
548 struct kvm_rmap_desc *desc,
550 struct kvm_rmap_desc *prev_desc)
554 for (j = RMAP_EXT - 1; !desc->sptes[j] && j > i; --j)
556 desc->sptes[i] = desc->sptes[j];
557 desc->sptes[j] = NULL;
560 if (!prev_desc && !desc->more)
561 *rmapp = (unsigned long)desc->sptes[0];
564 prev_desc->more = desc->more;
566 *rmapp = (unsigned long)desc->more | 1;
567 mmu_free_rmap_desc(desc);
570 static void rmap_remove(struct kvm *kvm, u64 *spte)
572 struct kvm_rmap_desc *desc;
573 struct kvm_rmap_desc *prev_desc;
574 struct kvm_mmu_page *sp;
576 unsigned long *rmapp;
579 if (!is_rmap_spte(*spte))
581 sp = page_header(__pa(spte));
582 pfn = spte_to_pfn(*spte);
583 if (*spte & shadow_accessed_mask)
584 kvm_set_pfn_accessed(pfn);
585 if (is_writeble_pte(*spte))
586 kvm_release_pfn_dirty(pfn);
588 kvm_release_pfn_clean(pfn);
589 rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt], is_large_pte(*spte));
591 printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte);
593 } else if (!(*rmapp & 1)) {
594 rmap_printk("rmap_remove: %p %llx 1->0\n", spte, *spte);
595 if ((u64 *)*rmapp != spte) {
596 printk(KERN_ERR "rmap_remove: %p %llx 1->BUG\n",
602 rmap_printk("rmap_remove: %p %llx many->many\n", spte, *spte);
603 desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
606 for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i)
607 if (desc->sptes[i] == spte) {
608 rmap_desc_remove_entry(rmapp,
620 static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte)
622 struct kvm_rmap_desc *desc;
623 struct kvm_rmap_desc *prev_desc;
629 else if (!(*rmapp & 1)) {
631 return (u64 *)*rmapp;
634 desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
638 for (i = 0; i < RMAP_EXT && desc->sptes[i]; ++i) {
639 if (prev_spte == spte)
640 return desc->sptes[i];
641 prev_spte = desc->sptes[i];
648 static int rmap_write_protect(struct kvm *kvm, u64 gfn)
650 unsigned long *rmapp;
652 int write_protected = 0;
654 gfn = unalias_gfn(kvm, gfn);
655 rmapp = gfn_to_rmap(kvm, gfn, 0);
657 spte = rmap_next(kvm, rmapp, NULL);
660 BUG_ON(!(*spte & PT_PRESENT_MASK));
661 rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte);
662 if (is_writeble_pte(*spte)) {
663 __set_spte(spte, *spte & ~PT_WRITABLE_MASK);
666 spte = rmap_next(kvm, rmapp, spte);
668 if (write_protected) {
671 spte = rmap_next(kvm, rmapp, NULL);
672 pfn = spte_to_pfn(*spte);
673 kvm_set_pfn_dirty(pfn);
676 /* check for huge page mappings */
677 rmapp = gfn_to_rmap(kvm, gfn, 1);
678 spte = rmap_next(kvm, rmapp, NULL);
681 BUG_ON(!(*spte & PT_PRESENT_MASK));
682 BUG_ON((*spte & (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK)) != (PT_PAGE_SIZE_MASK|PT_PRESENT_MASK));
683 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn);
684 if (is_writeble_pte(*spte)) {
685 rmap_remove(kvm, spte);
687 __set_spte(spte, shadow_trap_nonpresent_pte);
691 spte = rmap_next(kvm, rmapp, spte);
694 return write_protected;
697 static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp)
700 int need_tlb_flush = 0;
702 while ((spte = rmap_next(kvm, rmapp, NULL))) {
703 BUG_ON(!(*spte & PT_PRESENT_MASK));
704 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte, *spte);
705 rmap_remove(kvm, spte);
706 __set_spte(spte, shadow_trap_nonpresent_pte);
709 return need_tlb_flush;
712 static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
713 int (*handler)(struct kvm *kvm, unsigned long *rmapp))
719 * If mmap_sem isn't taken, we can look the memslots with only
720 * the mmu_lock by skipping over the slots with userspace_addr == 0.
722 for (i = 0; i < kvm->nmemslots; i++) {
723 struct kvm_memory_slot *memslot = &kvm->memslots[i];
724 unsigned long start = memslot->userspace_addr;
727 /* mmu_lock protects userspace_addr */
731 end = start + (memslot->npages << PAGE_SHIFT);
732 if (hva >= start && hva < end) {
733 gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT;
734 retval |= handler(kvm, &memslot->rmap[gfn_offset]);
735 retval |= handler(kvm,
736 &memslot->lpage_info[
738 KVM_PAGES_PER_HPAGE].rmap_pde);
745 int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
747 return kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
750 static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp)
755 /* always return old for EPT */
756 if (!shadow_accessed_mask)
759 spte = rmap_next(kvm, rmapp, NULL);
763 BUG_ON(!(_spte & PT_PRESENT_MASK));
764 _young = _spte & PT_ACCESSED_MASK;
767 clear_bit(PT_ACCESSED_SHIFT, (unsigned long *)spte);
769 spte = rmap_next(kvm, rmapp, spte);
774 #define RMAP_RECYCLE_THRESHOLD 1000
776 static void rmap_recycle(struct kvm_vcpu *vcpu, gfn_t gfn, int lpage)
778 unsigned long *rmapp;
780 gfn = unalias_gfn(vcpu->kvm, gfn);
781 rmapp = gfn_to_rmap(vcpu->kvm, gfn, lpage);
783 kvm_unmap_rmapp(vcpu->kvm, rmapp);
784 kvm_flush_remote_tlbs(vcpu->kvm);
787 int kvm_age_hva(struct kvm *kvm, unsigned long hva)
789 return kvm_handle_hva(kvm, hva, kvm_age_rmapp);
793 static int is_empty_shadow_page(u64 *spt)
798 for (pos = spt, end = pos + PAGE_SIZE / sizeof(u64); pos != end; pos++)
799 if (is_shadow_present_pte(*pos)) {
800 printk(KERN_ERR "%s: %p %llx\n", __func__,
808 static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp)
810 ASSERT(is_empty_shadow_page(sp->spt));
812 __free_page(virt_to_page(sp->spt));
813 __free_page(virt_to_page(sp->gfns));
815 ++kvm->arch.n_free_mmu_pages;
818 static unsigned kvm_page_table_hashfn(gfn_t gfn)
820 return gfn & ((1 << KVM_MMU_HASH_SHIFT) - 1);
823 static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu,
826 struct kvm_mmu_page *sp;
828 sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache, sizeof *sp);
829 sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
830 sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE);
831 set_page_private(virt_to_page(sp->spt), (unsigned long)sp);
832 list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages);
833 INIT_LIST_HEAD(&sp->oos_link);
834 bitmap_zero(sp->slot_bitmap, KVM_MEMORY_SLOTS + KVM_PRIVATE_MEM_SLOTS);
836 sp->parent_pte = parent_pte;
837 --vcpu->kvm->arch.n_free_mmu_pages;
841 static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu,
842 struct kvm_mmu_page *sp, u64 *parent_pte)
844 struct kvm_pte_chain *pte_chain;
845 struct hlist_node *node;
850 if (!sp->multimapped) {
851 u64 *old = sp->parent_pte;
854 sp->parent_pte = parent_pte;
858 pte_chain = mmu_alloc_pte_chain(vcpu);
859 INIT_HLIST_HEAD(&sp->parent_ptes);
860 hlist_add_head(&pte_chain->link, &sp->parent_ptes);
861 pte_chain->parent_ptes[0] = old;
863 hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) {
864 if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1])
866 for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i)
867 if (!pte_chain->parent_ptes[i]) {
868 pte_chain->parent_ptes[i] = parent_pte;
872 pte_chain = mmu_alloc_pte_chain(vcpu);
874 hlist_add_head(&pte_chain->link, &sp->parent_ptes);
875 pte_chain->parent_ptes[0] = parent_pte;
878 static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp,
881 struct kvm_pte_chain *pte_chain;
882 struct hlist_node *node;
885 if (!sp->multimapped) {
886 BUG_ON(sp->parent_pte != parent_pte);
887 sp->parent_pte = NULL;
890 hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
891 for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
892 if (!pte_chain->parent_ptes[i])
894 if (pte_chain->parent_ptes[i] != parent_pte)
896 while (i + 1 < NR_PTE_CHAIN_ENTRIES
897 && pte_chain->parent_ptes[i + 1]) {
898 pte_chain->parent_ptes[i]
899 = pte_chain->parent_ptes[i + 1];
902 pte_chain->parent_ptes[i] = NULL;
904 hlist_del(&pte_chain->link);
905 mmu_free_pte_chain(pte_chain);
906 if (hlist_empty(&sp->parent_ptes)) {
908 sp->parent_pte = NULL;
917 static void mmu_parent_walk(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,
918 mmu_parent_walk_fn fn)
920 struct kvm_pte_chain *pte_chain;
921 struct hlist_node *node;
922 struct kvm_mmu_page *parent_sp;
925 if (!sp->multimapped && sp->parent_pte) {
926 parent_sp = page_header(__pa(sp->parent_pte));
928 mmu_parent_walk(vcpu, parent_sp, fn);
931 hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
932 for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
933 if (!pte_chain->parent_ptes[i])
935 parent_sp = page_header(__pa(pte_chain->parent_ptes[i]));
937 mmu_parent_walk(vcpu, parent_sp, fn);
941 static void kvm_mmu_update_unsync_bitmap(u64 *spte)
944 struct kvm_mmu_page *sp = page_header(__pa(spte));
946 index = spte - sp->spt;
947 if (!__test_and_set_bit(index, sp->unsync_child_bitmap))
948 sp->unsync_children++;
949 WARN_ON(!sp->unsync_children);
952 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page *sp)
954 struct kvm_pte_chain *pte_chain;
955 struct hlist_node *node;
961 if (!sp->multimapped) {
962 kvm_mmu_update_unsync_bitmap(sp->parent_pte);
966 hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link)
967 for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) {
968 if (!pte_chain->parent_ptes[i])
970 kvm_mmu_update_unsync_bitmap(pte_chain->parent_ptes[i]);
974 static int unsync_walk_fn(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
976 kvm_mmu_update_parents_unsync(sp);
980 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu *vcpu,
981 struct kvm_mmu_page *sp)
983 mmu_parent_walk(vcpu, sp, unsync_walk_fn);
984 kvm_mmu_update_parents_unsync(sp);
987 static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu,
988 struct kvm_mmu_page *sp)
992 for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
993 sp->spt[i] = shadow_trap_nonpresent_pte;
996 static int nonpaging_sync_page(struct kvm_vcpu *vcpu,
997 struct kvm_mmu_page *sp)
1002 static void nonpaging_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
1006 #define KVM_PAGE_ARRAY_NR 16
1008 struct kvm_mmu_pages {
1009 struct mmu_page_and_offset {
1010 struct kvm_mmu_page *sp;
1012 } page[KVM_PAGE_ARRAY_NR];
1016 #define for_each_unsync_children(bitmap, idx) \
1017 for (idx = find_first_bit(bitmap, 512); \
1019 idx = find_next_bit(bitmap, 512, idx+1))
1021 static int mmu_pages_add(struct kvm_mmu_pages *pvec, struct kvm_mmu_page *sp,
1027 for (i=0; i < pvec->nr; i++)
1028 if (pvec->page[i].sp == sp)
1031 pvec->page[pvec->nr].sp = sp;
1032 pvec->page[pvec->nr].idx = idx;
1034 return (pvec->nr == KVM_PAGE_ARRAY_NR);
1037 static int __mmu_unsync_walk(struct kvm_mmu_page *sp,
1038 struct kvm_mmu_pages *pvec)
1040 int i, ret, nr_unsync_leaf = 0;
1042 for_each_unsync_children(sp->unsync_child_bitmap, i) {
1043 u64 ent = sp->spt[i];
1045 if (is_shadow_present_pte(ent) && !is_large_pte(ent)) {
1046 struct kvm_mmu_page *child;
1047 child = page_header(ent & PT64_BASE_ADDR_MASK);
1049 if (child->unsync_children) {
1050 if (mmu_pages_add(pvec, child, i))
1053 ret = __mmu_unsync_walk(child, pvec);
1055 __clear_bit(i, sp->unsync_child_bitmap);
1057 nr_unsync_leaf += ret;
1062 if (child->unsync) {
1064 if (mmu_pages_add(pvec, child, i))
1070 if (find_first_bit(sp->unsync_child_bitmap, 512) == 512)
1071 sp->unsync_children = 0;
1073 return nr_unsync_leaf;
1076 static int mmu_unsync_walk(struct kvm_mmu_page *sp,
1077 struct kvm_mmu_pages *pvec)
1079 if (!sp->unsync_children)
1082 mmu_pages_add(pvec, sp, 0);
1083 return __mmu_unsync_walk(sp, pvec);
1086 static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn)
1089 struct hlist_head *bucket;
1090 struct kvm_mmu_page *sp;
1091 struct hlist_node *node;
1093 pgprintk("%s: looking for gfn %lx\n", __func__, gfn);
1094 index = kvm_page_table_hashfn(gfn);
1095 bucket = &kvm->arch.mmu_page_hash[index];
1096 hlist_for_each_entry(sp, node, bucket, hash_link)
1097 if (sp->gfn == gfn && !sp->role.direct
1098 && !sp->role.invalid) {
1099 pgprintk("%s: found role %x\n",
1100 __func__, sp->role.word);
1106 static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp)
1108 WARN_ON(!sp->unsync);
1110 --kvm->stat.mmu_unsync;
1113 static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp);
1115 static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
1117 if (sp->role.glevels != vcpu->arch.mmu.root_level) {
1118 kvm_mmu_zap_page(vcpu->kvm, sp);
1122 if (rmap_write_protect(vcpu->kvm, sp->gfn))
1123 kvm_flush_remote_tlbs(vcpu->kvm);
1124 kvm_unlink_unsync_page(vcpu->kvm, sp);
1125 if (vcpu->arch.mmu.sync_page(vcpu, sp)) {
1126 kvm_mmu_zap_page(vcpu->kvm, sp);
1130 kvm_mmu_flush_tlb(vcpu);
1134 struct mmu_page_path {
1135 struct kvm_mmu_page *parent[PT64_ROOT_LEVEL-1];
1136 unsigned int idx[PT64_ROOT_LEVEL-1];
1139 #define for_each_sp(pvec, sp, parents, i) \
1140 for (i = mmu_pages_next(&pvec, &parents, -1), \
1141 sp = pvec.page[i].sp; \
1142 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1143 i = mmu_pages_next(&pvec, &parents, i))
1145 static int mmu_pages_next(struct kvm_mmu_pages *pvec,
1146 struct mmu_page_path *parents,
1151 for (n = i+1; n < pvec->nr; n++) {
1152 struct kvm_mmu_page *sp = pvec->page[n].sp;
1154 if (sp->role.level == PT_PAGE_TABLE_LEVEL) {
1155 parents->idx[0] = pvec->page[n].idx;
1159 parents->parent[sp->role.level-2] = sp;
1160 parents->idx[sp->role.level-1] = pvec->page[n].idx;
1166 static void mmu_pages_clear_parents(struct mmu_page_path *parents)
1168 struct kvm_mmu_page *sp;
1169 unsigned int level = 0;
1172 unsigned int idx = parents->idx[level];
1174 sp = parents->parent[level];
1178 --sp->unsync_children;
1179 WARN_ON((int)sp->unsync_children < 0);
1180 __clear_bit(idx, sp->unsync_child_bitmap);
1182 } while (level < PT64_ROOT_LEVEL-1 && !sp->unsync_children);
1185 static void kvm_mmu_pages_init(struct kvm_mmu_page *parent,
1186 struct mmu_page_path *parents,
1187 struct kvm_mmu_pages *pvec)
1189 parents->parent[parent->role.level-1] = NULL;
1193 static void mmu_sync_children(struct kvm_vcpu *vcpu,
1194 struct kvm_mmu_page *parent)
1197 struct kvm_mmu_page *sp;
1198 struct mmu_page_path parents;
1199 struct kvm_mmu_pages pages;
1201 kvm_mmu_pages_init(parent, &parents, &pages);
1202 while (mmu_unsync_walk(parent, &pages)) {
1205 for_each_sp(pages, sp, parents, i)
1206 protected |= rmap_write_protect(vcpu->kvm, sp->gfn);
1209 kvm_flush_remote_tlbs(vcpu->kvm);
1211 for_each_sp(pages, sp, parents, i) {
1212 kvm_sync_page(vcpu, sp);
1213 mmu_pages_clear_parents(&parents);
1215 cond_resched_lock(&vcpu->kvm->mmu_lock);
1216 kvm_mmu_pages_init(parent, &parents, &pages);
1220 static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu,
1228 union kvm_mmu_page_role role;
1231 struct hlist_head *bucket;
1232 struct kvm_mmu_page *sp;
1233 struct hlist_node *node, *tmp;
1235 role = vcpu->arch.mmu.base_role;
1237 role.direct = direct;
1238 role.access = access;
1239 if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) {
1240 quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level));
1241 quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1;
1242 role.quadrant = quadrant;
1244 pgprintk("%s: looking gfn %lx role %x\n", __func__,
1246 index = kvm_page_table_hashfn(gfn);
1247 bucket = &vcpu->kvm->arch.mmu_page_hash[index];
1248 hlist_for_each_entry_safe(sp, node, tmp, bucket, hash_link)
1249 if (sp->gfn == gfn) {
1251 if (kvm_sync_page(vcpu, sp))
1254 if (sp->role.word != role.word)
1257 mmu_page_add_parent_pte(vcpu, sp, parent_pte);
1258 if (sp->unsync_children) {
1259 set_bit(KVM_REQ_MMU_SYNC, &vcpu->requests);
1260 kvm_mmu_mark_parents_unsync(vcpu, sp);
1262 pgprintk("%s: found\n", __func__);
1265 ++vcpu->kvm->stat.mmu_cache_miss;
1266 sp = kvm_mmu_alloc_page(vcpu, parent_pte);
1269 pgprintk("%s: adding gfn %lx role %x\n", __func__, gfn, role.word);
1272 hlist_add_head(&sp->hash_link, bucket);
1274 if (rmap_write_protect(vcpu->kvm, gfn))
1275 kvm_flush_remote_tlbs(vcpu->kvm);
1276 account_shadowed(vcpu->kvm, gfn);
1278 if (shadow_trap_nonpresent_pte != shadow_notrap_nonpresent_pte)
1279 vcpu->arch.mmu.prefetch_page(vcpu, sp);
1281 nonpaging_prefetch_page(vcpu, sp);
1285 static void shadow_walk_init(struct kvm_shadow_walk_iterator *iterator,
1286 struct kvm_vcpu *vcpu, u64 addr)
1288 iterator->addr = addr;
1289 iterator->shadow_addr = vcpu->arch.mmu.root_hpa;
1290 iterator->level = vcpu->arch.mmu.shadow_root_level;
1291 if (iterator->level == PT32E_ROOT_LEVEL) {
1292 iterator->shadow_addr
1293 = vcpu->arch.mmu.pae_root[(addr >> 30) & 3];
1294 iterator->shadow_addr &= PT64_BASE_ADDR_MASK;
1296 if (!iterator->shadow_addr)
1297 iterator->level = 0;
1301 static bool shadow_walk_okay(struct kvm_shadow_walk_iterator *iterator)
1303 if (iterator->level < PT_PAGE_TABLE_LEVEL)
1306 if (iterator->level == PT_PAGE_TABLE_LEVEL)
1307 if (is_large_pte(*iterator->sptep))
1310 iterator->index = SHADOW_PT_INDEX(iterator->addr, iterator->level);
1311 iterator->sptep = ((u64 *)__va(iterator->shadow_addr)) + iterator->index;
1315 static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator)
1317 iterator->shadow_addr = *iterator->sptep & PT64_BASE_ADDR_MASK;
1321 static void kvm_mmu_page_unlink_children(struct kvm *kvm,
1322 struct kvm_mmu_page *sp)
1330 for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
1333 if (is_shadow_present_pte(ent)) {
1334 if (!is_last_spte(ent, sp->role.level)) {
1335 ent &= PT64_BASE_ADDR_MASK;
1336 mmu_page_remove_parent_pte(page_header(ent),
1339 if (is_large_pte(ent))
1341 rmap_remove(kvm, &pt[i]);
1344 pt[i] = shadow_trap_nonpresent_pte;
1348 static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte)
1350 mmu_page_remove_parent_pte(sp, parent_pte);
1353 static void kvm_mmu_reset_last_pte_updated(struct kvm *kvm)
1356 struct kvm_vcpu *vcpu;
1358 kvm_for_each_vcpu(i, vcpu, kvm)
1359 vcpu->arch.last_pte_updated = NULL;
1362 static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp)
1366 while (sp->multimapped || sp->parent_pte) {
1367 if (!sp->multimapped)
1368 parent_pte = sp->parent_pte;
1370 struct kvm_pte_chain *chain;
1372 chain = container_of(sp->parent_ptes.first,
1373 struct kvm_pte_chain, link);
1374 parent_pte = chain->parent_ptes[0];
1376 BUG_ON(!parent_pte);
1377 kvm_mmu_put_page(sp, parent_pte);
1378 __set_spte(parent_pte, shadow_trap_nonpresent_pte);
1382 static int mmu_zap_unsync_children(struct kvm *kvm,
1383 struct kvm_mmu_page *parent)
1386 struct mmu_page_path parents;
1387 struct kvm_mmu_pages pages;
1389 if (parent->role.level == PT_PAGE_TABLE_LEVEL)
1392 kvm_mmu_pages_init(parent, &parents, &pages);
1393 while (mmu_unsync_walk(parent, &pages)) {
1394 struct kvm_mmu_page *sp;
1396 for_each_sp(pages, sp, parents, i) {
1397 kvm_mmu_zap_page(kvm, sp);
1398 mmu_pages_clear_parents(&parents);
1401 kvm_mmu_pages_init(parent, &parents, &pages);
1407 static int kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp)
1410 ++kvm->stat.mmu_shadow_zapped;
1411 ret = mmu_zap_unsync_children(kvm, sp);
1412 kvm_mmu_page_unlink_children(kvm, sp);
1413 kvm_mmu_unlink_parents(kvm, sp);
1414 kvm_flush_remote_tlbs(kvm);
1415 if (!sp->role.invalid && !sp->role.direct)
1416 unaccount_shadowed(kvm, sp->gfn);
1418 kvm_unlink_unsync_page(kvm, sp);
1419 if (!sp->root_count) {
1420 hlist_del(&sp->hash_link);
1421 kvm_mmu_free_page(kvm, sp);
1423 sp->role.invalid = 1;
1424 list_move(&sp->link, &kvm->arch.active_mmu_pages);
1425 kvm_reload_remote_mmus(kvm);
1427 kvm_mmu_reset_last_pte_updated(kvm);
1432 * Changing the number of mmu pages allocated to the vm
1433 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1435 void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages)
1439 used_pages = kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages;
1440 used_pages = max(0, used_pages);
1443 * If we set the number of mmu pages to be smaller be than the
1444 * number of actived pages , we must to free some mmu pages before we
1448 if (used_pages > kvm_nr_mmu_pages) {
1449 while (used_pages > kvm_nr_mmu_pages) {
1450 struct kvm_mmu_page *page;
1452 page = container_of(kvm->arch.active_mmu_pages.prev,
1453 struct kvm_mmu_page, link);
1454 kvm_mmu_zap_page(kvm, page);
1457 kvm->arch.n_free_mmu_pages = 0;
1460 kvm->arch.n_free_mmu_pages += kvm_nr_mmu_pages
1461 - kvm->arch.n_alloc_mmu_pages;
1463 kvm->arch.n_alloc_mmu_pages = kvm_nr_mmu_pages;
1466 static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn)
1469 struct hlist_head *bucket;
1470 struct kvm_mmu_page *sp;
1471 struct hlist_node *node, *n;
1474 pgprintk("%s: looking for gfn %lx\n", __func__, gfn);
1476 index = kvm_page_table_hashfn(gfn);
1477 bucket = &kvm->arch.mmu_page_hash[index];
1478 hlist_for_each_entry_safe(sp, node, n, bucket, hash_link)
1479 if (sp->gfn == gfn && !sp->role.direct) {
1480 pgprintk("%s: gfn %lx role %x\n", __func__, gfn,
1483 if (kvm_mmu_zap_page(kvm, sp))
1489 static void mmu_unshadow(struct kvm *kvm, gfn_t gfn)
1492 struct hlist_head *bucket;
1493 struct kvm_mmu_page *sp;
1494 struct hlist_node *node, *nn;
1496 index = kvm_page_table_hashfn(gfn);
1497 bucket = &kvm->arch.mmu_page_hash[index];
1498 hlist_for_each_entry_safe(sp, node, nn, bucket, hash_link) {
1499 if (sp->gfn == gfn && !sp->role.direct
1500 && !sp->role.invalid) {
1501 pgprintk("%s: zap %lx %x\n",
1502 __func__, gfn, sp->role.word);
1503 kvm_mmu_zap_page(kvm, sp);
1508 static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn)
1510 int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn));
1511 struct kvm_mmu_page *sp = page_header(__pa(pte));
1513 __set_bit(slot, sp->slot_bitmap);
1516 static void mmu_convert_notrap(struct kvm_mmu_page *sp)
1521 if (shadow_trap_nonpresent_pte == shadow_notrap_nonpresent_pte)
1524 for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
1525 if (pt[i] == shadow_notrap_nonpresent_pte)
1526 __set_spte(&pt[i], shadow_trap_nonpresent_pte);
1530 struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva)
1534 gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva);
1536 if (gpa == UNMAPPED_GVA)
1539 page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT);
1545 * The function is based on mtrr_type_lookup() in
1546 * arch/x86/kernel/cpu/mtrr/generic.c
1548 static int get_mtrr_type(struct mtrr_state_type *mtrr_state,
1553 u8 prev_match, curr_match;
1554 int num_var_ranges = KVM_NR_VAR_MTRR;
1556 if (!mtrr_state->enabled)
1559 /* Make end inclusive end, instead of exclusive */
1562 /* Look in fixed ranges. Just return the type as per start */
1563 if (mtrr_state->have_fixed && (start < 0x100000)) {
1566 if (start < 0x80000) {
1568 idx += (start >> 16);
1569 return mtrr_state->fixed_ranges[idx];
1570 } else if (start < 0xC0000) {
1572 idx += ((start - 0x80000) >> 14);
1573 return mtrr_state->fixed_ranges[idx];
1574 } else if (start < 0x1000000) {
1576 idx += ((start - 0xC0000) >> 12);
1577 return mtrr_state->fixed_ranges[idx];
1582 * Look in variable ranges
1583 * Look of multiple ranges matching this address and pick type
1584 * as per MTRR precedence
1586 if (!(mtrr_state->enabled & 2))
1587 return mtrr_state->def_type;
1590 for (i = 0; i < num_var_ranges; ++i) {
1591 unsigned short start_state, end_state;
1593 if (!(mtrr_state->var_ranges[i].mask_lo & (1 << 11)))
1596 base = (((u64)mtrr_state->var_ranges[i].base_hi) << 32) +
1597 (mtrr_state->var_ranges[i].base_lo & PAGE_MASK);
1598 mask = (((u64)mtrr_state->var_ranges[i].mask_hi) << 32) +
1599 (mtrr_state->var_ranges[i].mask_lo & PAGE_MASK);
1601 start_state = ((start & mask) == (base & mask));
1602 end_state = ((end & mask) == (base & mask));
1603 if (start_state != end_state)
1606 if ((start & mask) != (base & mask))
1609 curr_match = mtrr_state->var_ranges[i].base_lo & 0xff;
1610 if (prev_match == 0xFF) {
1611 prev_match = curr_match;
1615 if (prev_match == MTRR_TYPE_UNCACHABLE ||
1616 curr_match == MTRR_TYPE_UNCACHABLE)
1617 return MTRR_TYPE_UNCACHABLE;
1619 if ((prev_match == MTRR_TYPE_WRBACK &&
1620 curr_match == MTRR_TYPE_WRTHROUGH) ||
1621 (prev_match == MTRR_TYPE_WRTHROUGH &&
1622 curr_match == MTRR_TYPE_WRBACK)) {
1623 prev_match = MTRR_TYPE_WRTHROUGH;
1624 curr_match = MTRR_TYPE_WRTHROUGH;
1627 if (prev_match != curr_match)
1628 return MTRR_TYPE_UNCACHABLE;
1631 if (prev_match != 0xFF)
1634 return mtrr_state->def_type;
1637 u8 kvm_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn)
1641 mtrr = get_mtrr_type(&vcpu->arch.mtrr_state, gfn << PAGE_SHIFT,
1642 (gfn << PAGE_SHIFT) + PAGE_SIZE);
1643 if (mtrr == 0xfe || mtrr == 0xff)
1644 mtrr = MTRR_TYPE_WRBACK;
1647 EXPORT_SYMBOL_GPL(kvm_get_guest_memory_type);
1649 static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
1652 struct hlist_head *bucket;
1653 struct kvm_mmu_page *s;
1654 struct hlist_node *node, *n;
1656 index = kvm_page_table_hashfn(sp->gfn);
1657 bucket = &vcpu->kvm->arch.mmu_page_hash[index];
1658 /* don't unsync if pagetable is shadowed with multiple roles */
1659 hlist_for_each_entry_safe(s, node, n, bucket, hash_link) {
1660 if (s->gfn != sp->gfn || s->role.direct)
1662 if (s->role.word != sp->role.word)
1665 ++vcpu->kvm->stat.mmu_unsync;
1668 kvm_mmu_mark_parents_unsync(vcpu, sp);
1670 mmu_convert_notrap(sp);
1674 static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
1677 struct kvm_mmu_page *shadow;
1679 shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn);
1681 if (shadow->role.level != PT_PAGE_TABLE_LEVEL)
1685 if (can_unsync && oos_shadow)
1686 return kvm_unsync_page(vcpu, shadow);
1692 static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
1693 unsigned pte_access, int user_fault,
1694 int write_fault, int dirty, int largepage,
1695 gfn_t gfn, pfn_t pfn, bool speculative,
1702 * We don't set the accessed bit, since we sometimes want to see
1703 * whether the guest actually used the pte (in order to detect
1706 spte = shadow_base_present_pte | shadow_dirty_mask;
1708 spte |= shadow_accessed_mask;
1710 pte_access &= ~ACC_WRITE_MASK;
1711 if (pte_access & ACC_EXEC_MASK)
1712 spte |= shadow_x_mask;
1714 spte |= shadow_nx_mask;
1715 if (pte_access & ACC_USER_MASK)
1716 spte |= shadow_user_mask;
1718 spte |= PT_PAGE_SIZE_MASK;
1720 spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn,
1721 kvm_is_mmio_pfn(pfn));
1723 spte |= (u64)pfn << PAGE_SHIFT;
1725 if ((pte_access & ACC_WRITE_MASK)
1726 || (write_fault && !is_write_protection(vcpu) && !user_fault)) {
1728 if (largepage && has_wrprotected_page(vcpu->kvm, gfn)) {
1730 spte = shadow_trap_nonpresent_pte;
1734 spte |= PT_WRITABLE_MASK;
1737 * Optimization: for pte sync, if spte was writable the hash
1738 * lookup is unnecessary (and expensive). Write protection
1739 * is responsibility of mmu_get_page / kvm_sync_page.
1740 * Same reasoning can be applied to dirty page accounting.
1742 if (!can_unsync && is_writeble_pte(*sptep))
1745 if (mmu_need_write_protect(vcpu, gfn, can_unsync)) {
1746 pgprintk("%s: found shadow page for %lx, marking ro\n",
1749 pte_access &= ~ACC_WRITE_MASK;
1750 if (is_writeble_pte(spte))
1751 spte &= ~PT_WRITABLE_MASK;
1755 if (pte_access & ACC_WRITE_MASK)
1756 mark_page_dirty(vcpu->kvm, gfn);
1759 __set_spte(sptep, spte);
1763 static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
1764 unsigned pt_access, unsigned pte_access,
1765 int user_fault, int write_fault, int dirty,
1766 int *ptwrite, int largepage, gfn_t gfn,
1767 pfn_t pfn, bool speculative)
1769 int was_rmapped = 0;
1770 int was_writeble = is_writeble_pte(*sptep);
1773 pgprintk("%s: spte %llx access %x write_fault %d"
1774 " user_fault %d gfn %lx\n",
1775 __func__, *sptep, pt_access,
1776 write_fault, user_fault, gfn);
1778 if (is_rmap_spte(*sptep)) {
1780 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1781 * the parent of the now unreachable PTE.
1783 if (largepage && !is_large_pte(*sptep)) {
1784 struct kvm_mmu_page *child;
1787 child = page_header(pte & PT64_BASE_ADDR_MASK);
1788 mmu_page_remove_parent_pte(child, sptep);
1789 } else if (pfn != spte_to_pfn(*sptep)) {
1790 pgprintk("hfn old %lx new %lx\n",
1791 spte_to_pfn(*sptep), pfn);
1792 rmap_remove(vcpu->kvm, sptep);
1796 if (set_spte(vcpu, sptep, pte_access, user_fault, write_fault,
1797 dirty, largepage, gfn, pfn, speculative, true)) {
1800 kvm_x86_ops->tlb_flush(vcpu);
1803 pgprintk("%s: setting spte %llx\n", __func__, *sptep);
1804 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1805 is_large_pte(*sptep)? "2MB" : "4kB",
1806 is_present_pte(*sptep)?"RW":"R", gfn,
1807 *shadow_pte, sptep);
1808 if (!was_rmapped && is_large_pte(*sptep))
1809 ++vcpu->kvm->stat.lpages;
1811 page_header_update_slot(vcpu->kvm, sptep, gfn);
1813 rmap_count = rmap_add(vcpu, sptep, gfn, largepage);
1814 if (!is_rmap_spte(*sptep))
1815 kvm_release_pfn_clean(pfn);
1816 if (rmap_count > RMAP_RECYCLE_THRESHOLD)
1817 rmap_recycle(vcpu, gfn, largepage);
1820 kvm_release_pfn_dirty(pfn);
1822 kvm_release_pfn_clean(pfn);
1825 vcpu->arch.last_pte_updated = sptep;
1826 vcpu->arch.last_pte_gfn = gfn;
1830 static void nonpaging_new_cr3(struct kvm_vcpu *vcpu)
1834 static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write,
1835 int largepage, gfn_t gfn, pfn_t pfn)
1837 struct kvm_shadow_walk_iterator iterator;
1838 struct kvm_mmu_page *sp;
1842 for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) {
1843 if (iterator.level == PT_PAGE_TABLE_LEVEL
1844 || (largepage && iterator.level == PT_DIRECTORY_LEVEL)) {
1845 mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, ACC_ALL,
1846 0, write, 1, &pt_write,
1847 largepage, gfn, pfn, false);
1848 ++vcpu->stat.pf_fixed;
1852 if (*iterator.sptep == shadow_trap_nonpresent_pte) {
1853 pseudo_gfn = (iterator.addr & PT64_DIR_BASE_ADDR_MASK) >> PAGE_SHIFT;
1854 sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr,
1856 1, ACC_ALL, iterator.sptep);
1858 pgprintk("nonpaging_map: ENOMEM\n");
1859 kvm_release_pfn_clean(pfn);
1863 __set_spte(iterator.sptep,
1865 | PT_PRESENT_MASK | PT_WRITABLE_MASK
1866 | shadow_user_mask | shadow_x_mask);
1872 static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn)
1877 unsigned long mmu_seq;
1879 if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) {
1880 gfn &= ~(KVM_PAGES_PER_HPAGE-1);
1884 mmu_seq = vcpu->kvm->mmu_notifier_seq;
1886 pfn = gfn_to_pfn(vcpu->kvm, gfn);
1889 if (is_error_pfn(pfn)) {
1890 kvm_release_pfn_clean(pfn);
1894 spin_lock(&vcpu->kvm->mmu_lock);
1895 if (mmu_notifier_retry(vcpu, mmu_seq))
1897 kvm_mmu_free_some_pages(vcpu);
1898 r = __direct_map(vcpu, v, write, largepage, gfn, pfn);
1899 spin_unlock(&vcpu->kvm->mmu_lock);
1905 spin_unlock(&vcpu->kvm->mmu_lock);
1906 kvm_release_pfn_clean(pfn);
1911 static void mmu_free_roots(struct kvm_vcpu *vcpu)
1914 struct kvm_mmu_page *sp;
1916 if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
1918 spin_lock(&vcpu->kvm->mmu_lock);
1919 if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
1920 hpa_t root = vcpu->arch.mmu.root_hpa;
1922 sp = page_header(root);
1924 if (!sp->root_count && sp->role.invalid)
1925 kvm_mmu_zap_page(vcpu->kvm, sp);
1926 vcpu->arch.mmu.root_hpa = INVALID_PAGE;
1927 spin_unlock(&vcpu->kvm->mmu_lock);
1930 for (i = 0; i < 4; ++i) {
1931 hpa_t root = vcpu->arch.mmu.pae_root[i];
1934 root &= PT64_BASE_ADDR_MASK;
1935 sp = page_header(root);
1937 if (!sp->root_count && sp->role.invalid)
1938 kvm_mmu_zap_page(vcpu->kvm, sp);
1940 vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
1942 spin_unlock(&vcpu->kvm->mmu_lock);
1943 vcpu->arch.mmu.root_hpa = INVALID_PAGE;
1946 static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn)
1950 if (!kvm_is_visible_gfn(vcpu->kvm, root_gfn)) {
1951 set_bit(KVM_REQ_TRIPLE_FAULT, &vcpu->requests);
1958 static int mmu_alloc_roots(struct kvm_vcpu *vcpu)
1962 struct kvm_mmu_page *sp;
1966 root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT;
1968 if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
1969 hpa_t root = vcpu->arch.mmu.root_hpa;
1971 ASSERT(!VALID_PAGE(root));
1974 if (mmu_check_root(vcpu, root_gfn))
1976 sp = kvm_mmu_get_page(vcpu, root_gfn, 0,
1977 PT64_ROOT_LEVEL, direct,
1979 root = __pa(sp->spt);
1981 vcpu->arch.mmu.root_hpa = root;
1984 direct = !is_paging(vcpu);
1987 for (i = 0; i < 4; ++i) {
1988 hpa_t root = vcpu->arch.mmu.pae_root[i];
1990 ASSERT(!VALID_PAGE(root));
1991 if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) {
1992 pdptr = kvm_pdptr_read(vcpu, i);
1993 if (!is_present_gpte(pdptr)) {
1994 vcpu->arch.mmu.pae_root[i] = 0;
1997 root_gfn = pdptr >> PAGE_SHIFT;
1998 } else if (vcpu->arch.mmu.root_level == 0)
2000 if (mmu_check_root(vcpu, root_gfn))
2002 sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30,
2003 PT32_ROOT_LEVEL, direct,
2005 root = __pa(sp->spt);
2007 vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK;
2009 vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root);
2013 static void mmu_sync_roots(struct kvm_vcpu *vcpu)
2016 struct kvm_mmu_page *sp;
2018 if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
2020 if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
2021 hpa_t root = vcpu->arch.mmu.root_hpa;
2022 sp = page_header(root);
2023 mmu_sync_children(vcpu, sp);
2026 for (i = 0; i < 4; ++i) {
2027 hpa_t root = vcpu->arch.mmu.pae_root[i];
2029 if (root && VALID_PAGE(root)) {
2030 root &= PT64_BASE_ADDR_MASK;
2031 sp = page_header(root);
2032 mmu_sync_children(vcpu, sp);
2037 void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
2039 spin_lock(&vcpu->kvm->mmu_lock);
2040 mmu_sync_roots(vcpu);
2041 spin_unlock(&vcpu->kvm->mmu_lock);
2044 static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr)
2049 static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva,
2055 pgprintk("%s: gva %lx error %x\n", __func__, gva, error_code);
2056 r = mmu_topup_memory_caches(vcpu);
2061 ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));
2063 gfn = gva >> PAGE_SHIFT;
2065 return nonpaging_map(vcpu, gva & PAGE_MASK,
2066 error_code & PFERR_WRITE_MASK, gfn);
2069 static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa,
2075 gfn_t gfn = gpa >> PAGE_SHIFT;
2076 unsigned long mmu_seq;
2079 ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa));
2081 r = mmu_topup_memory_caches(vcpu);
2085 if (is_largepage_backed(vcpu, gfn & ~(KVM_PAGES_PER_HPAGE-1))) {
2086 gfn &= ~(KVM_PAGES_PER_HPAGE-1);
2089 mmu_seq = vcpu->kvm->mmu_notifier_seq;
2091 pfn = gfn_to_pfn(vcpu->kvm, gfn);
2092 if (is_error_pfn(pfn)) {
2093 kvm_release_pfn_clean(pfn);
2096 spin_lock(&vcpu->kvm->mmu_lock);
2097 if (mmu_notifier_retry(vcpu, mmu_seq))
2099 kvm_mmu_free_some_pages(vcpu);
2100 r = __direct_map(vcpu, gpa, error_code & PFERR_WRITE_MASK,
2101 largepage, gfn, pfn);
2102 spin_unlock(&vcpu->kvm->mmu_lock);
2107 spin_unlock(&vcpu->kvm->mmu_lock);
2108 kvm_release_pfn_clean(pfn);
2112 static void nonpaging_free(struct kvm_vcpu *vcpu)
2114 mmu_free_roots(vcpu);
2117 static int nonpaging_init_context(struct kvm_vcpu *vcpu)
2119 struct kvm_mmu *context = &vcpu->arch.mmu;
2121 context->new_cr3 = nonpaging_new_cr3;
2122 context->page_fault = nonpaging_page_fault;
2123 context->gva_to_gpa = nonpaging_gva_to_gpa;
2124 context->free = nonpaging_free;
2125 context->prefetch_page = nonpaging_prefetch_page;
2126 context->sync_page = nonpaging_sync_page;
2127 context->invlpg = nonpaging_invlpg;
2128 context->root_level = 0;
2129 context->shadow_root_level = PT32E_ROOT_LEVEL;
2130 context->root_hpa = INVALID_PAGE;
2134 void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu)
2136 ++vcpu->stat.tlb_flush;
2137 kvm_x86_ops->tlb_flush(vcpu);
2140 static void paging_new_cr3(struct kvm_vcpu *vcpu)
2142 pgprintk("%s: cr3 %lx\n", __func__, vcpu->arch.cr3);
2143 mmu_free_roots(vcpu);
2146 static void inject_page_fault(struct kvm_vcpu *vcpu,
2150 kvm_inject_page_fault(vcpu, addr, err_code);
2153 static void paging_free(struct kvm_vcpu *vcpu)
2155 nonpaging_free(vcpu);
2158 static bool is_rsvd_bits_set(struct kvm_vcpu *vcpu, u64 gpte, int level)
2162 bit7 = (gpte >> 7) & 1;
2163 return (gpte & vcpu->arch.mmu.rsvd_bits_mask[bit7][level-1]) != 0;
2167 #include "paging_tmpl.h"
2171 #include "paging_tmpl.h"
2174 static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, int level)
2176 struct kvm_mmu *context = &vcpu->arch.mmu;
2177 int maxphyaddr = cpuid_maxphyaddr(vcpu);
2178 u64 exb_bit_rsvd = 0;
2181 exb_bit_rsvd = rsvd_bits(63, 63);
2183 case PT32_ROOT_LEVEL:
2184 /* no rsvd bits for 2 level 4K page table entries */
2185 context->rsvd_bits_mask[0][1] = 0;
2186 context->rsvd_bits_mask[0][0] = 0;
2187 if (is_cpuid_PSE36())
2188 /* 36bits PSE 4MB page */
2189 context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21);
2191 /* 32 bits PSE 4MB page */
2192 context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21);
2193 context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
2195 case PT32E_ROOT_LEVEL:
2196 context->rsvd_bits_mask[0][2] =
2197 rsvd_bits(maxphyaddr, 63) |
2198 rsvd_bits(7, 8) | rsvd_bits(1, 2); /* PDPTE */
2199 context->rsvd_bits_mask[0][1] = exb_bit_rsvd |
2200 rsvd_bits(maxphyaddr, 62); /* PDE */
2201 context->rsvd_bits_mask[0][0] = exb_bit_rsvd |
2202 rsvd_bits(maxphyaddr, 62); /* PTE */
2203 context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
2204 rsvd_bits(maxphyaddr, 62) |
2205 rsvd_bits(13, 20); /* large page */
2206 context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
2208 case PT64_ROOT_LEVEL:
2209 context->rsvd_bits_mask[0][3] = exb_bit_rsvd |
2210 rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
2211 context->rsvd_bits_mask[0][2] = exb_bit_rsvd |
2212 rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8);
2213 context->rsvd_bits_mask[0][1] = exb_bit_rsvd |
2214 rsvd_bits(maxphyaddr, 51);
2215 context->rsvd_bits_mask[0][0] = exb_bit_rsvd |
2216 rsvd_bits(maxphyaddr, 51);
2217 context->rsvd_bits_mask[1][3] = context->rsvd_bits_mask[0][3];
2218 context->rsvd_bits_mask[1][2] = context->rsvd_bits_mask[0][2];
2219 context->rsvd_bits_mask[1][1] = exb_bit_rsvd |
2220 rsvd_bits(maxphyaddr, 51) |
2221 rsvd_bits(13, 20); /* large page */
2222 context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[1][0];
2227 static int paging64_init_context_common(struct kvm_vcpu *vcpu, int level)
2229 struct kvm_mmu *context = &vcpu->arch.mmu;
2231 ASSERT(is_pae(vcpu));
2232 context->new_cr3 = paging_new_cr3;
2233 context->page_fault = paging64_page_fault;
2234 context->gva_to_gpa = paging64_gva_to_gpa;
2235 context->prefetch_page = paging64_prefetch_page;
2236 context->sync_page = paging64_sync_page;
2237 context->invlpg = paging64_invlpg;
2238 context->free = paging_free;
2239 context->root_level = level;
2240 context->shadow_root_level = level;
2241 context->root_hpa = INVALID_PAGE;
2245 static int paging64_init_context(struct kvm_vcpu *vcpu)
2247 reset_rsvds_bits_mask(vcpu, PT64_ROOT_LEVEL);
2248 return paging64_init_context_common(vcpu, PT64_ROOT_LEVEL);
2251 static int paging32_init_context(struct kvm_vcpu *vcpu)
2253 struct kvm_mmu *context = &vcpu->arch.mmu;
2255 reset_rsvds_bits_mask(vcpu, PT32_ROOT_LEVEL);
2256 context->new_cr3 = paging_new_cr3;
2257 context->page_fault = paging32_page_fault;
2258 context->gva_to_gpa = paging32_gva_to_gpa;
2259 context->free = paging_free;
2260 context->prefetch_page = paging32_prefetch_page;
2261 context->sync_page = paging32_sync_page;
2262 context->invlpg = paging32_invlpg;
2263 context->root_level = PT32_ROOT_LEVEL;
2264 context->shadow_root_level = PT32E_ROOT_LEVEL;
2265 context->root_hpa = INVALID_PAGE;
2269 static int paging32E_init_context(struct kvm_vcpu *vcpu)
2271 reset_rsvds_bits_mask(vcpu, PT32E_ROOT_LEVEL);
2272 return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL);
2275 static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu)
2277 struct kvm_mmu *context = &vcpu->arch.mmu;
2279 context->new_cr3 = nonpaging_new_cr3;
2280 context->page_fault = tdp_page_fault;
2281 context->free = nonpaging_free;
2282 context->prefetch_page = nonpaging_prefetch_page;
2283 context->sync_page = nonpaging_sync_page;
2284 context->invlpg = nonpaging_invlpg;
2285 context->shadow_root_level = kvm_x86_ops->get_tdp_level();
2286 context->root_hpa = INVALID_PAGE;
2288 if (!is_paging(vcpu)) {
2289 context->gva_to_gpa = nonpaging_gva_to_gpa;
2290 context->root_level = 0;
2291 } else if (is_long_mode(vcpu)) {
2292 reset_rsvds_bits_mask(vcpu, PT64_ROOT_LEVEL);
2293 context->gva_to_gpa = paging64_gva_to_gpa;
2294 context->root_level = PT64_ROOT_LEVEL;
2295 } else if (is_pae(vcpu)) {
2296 reset_rsvds_bits_mask(vcpu, PT32E_ROOT_LEVEL);
2297 context->gva_to_gpa = paging64_gva_to_gpa;
2298 context->root_level = PT32E_ROOT_LEVEL;
2300 reset_rsvds_bits_mask(vcpu, PT32_ROOT_LEVEL);
2301 context->gva_to_gpa = paging32_gva_to_gpa;
2302 context->root_level = PT32_ROOT_LEVEL;
2308 static int init_kvm_softmmu(struct kvm_vcpu *vcpu)
2313 ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
2315 if (!is_paging(vcpu))
2316 r = nonpaging_init_context(vcpu);
2317 else if (is_long_mode(vcpu))
2318 r = paging64_init_context(vcpu);
2319 else if (is_pae(vcpu))
2320 r = paging32E_init_context(vcpu);
2322 r = paging32_init_context(vcpu);
2324 vcpu->arch.mmu.base_role.glevels = vcpu->arch.mmu.root_level;
2329 static int init_kvm_mmu(struct kvm_vcpu *vcpu)
2331 vcpu->arch.update_pte.pfn = bad_pfn;
2334 return init_kvm_tdp_mmu(vcpu);
2336 return init_kvm_softmmu(vcpu);
2339 static void destroy_kvm_mmu(struct kvm_vcpu *vcpu)
2342 if (VALID_PAGE(vcpu->arch.mmu.root_hpa)) {
2343 vcpu->arch.mmu.free(vcpu);
2344 vcpu->arch.mmu.root_hpa = INVALID_PAGE;
2348 int kvm_mmu_reset_context(struct kvm_vcpu *vcpu)
2350 destroy_kvm_mmu(vcpu);
2351 return init_kvm_mmu(vcpu);
2353 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context);
2355 int kvm_mmu_load(struct kvm_vcpu *vcpu)
2359 r = mmu_topup_memory_caches(vcpu);
2362 spin_lock(&vcpu->kvm->mmu_lock);
2363 kvm_mmu_free_some_pages(vcpu);
2364 r = mmu_alloc_roots(vcpu);
2365 mmu_sync_roots(vcpu);
2366 spin_unlock(&vcpu->kvm->mmu_lock);
2369 kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa);
2370 kvm_mmu_flush_tlb(vcpu);
2374 EXPORT_SYMBOL_GPL(kvm_mmu_load);
2376 void kvm_mmu_unload(struct kvm_vcpu *vcpu)
2378 mmu_free_roots(vcpu);
2381 static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu,
2382 struct kvm_mmu_page *sp,
2386 struct kvm_mmu_page *child;
2389 if (is_shadow_present_pte(pte)) {
2390 if (is_last_spte(pte, sp->role.level))
2391 rmap_remove(vcpu->kvm, spte);
2393 child = page_header(pte & PT64_BASE_ADDR_MASK);
2394 mmu_page_remove_parent_pte(child, spte);
2397 __set_spte(spte, shadow_trap_nonpresent_pte);
2398 if (is_large_pte(pte))
2399 --vcpu->kvm->stat.lpages;
2402 static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu,
2403 struct kvm_mmu_page *sp,
2407 if (sp->role.level != PT_PAGE_TABLE_LEVEL) {
2408 if (!vcpu->arch.update_pte.largepage ||
2409 sp->role.glevels == PT32_ROOT_LEVEL) {
2410 ++vcpu->kvm->stat.mmu_pde_zapped;
2415 ++vcpu->kvm->stat.mmu_pte_updated;
2416 if (sp->role.glevels == PT32_ROOT_LEVEL)
2417 paging32_update_pte(vcpu, sp, spte, new);
2419 paging64_update_pte(vcpu, sp, spte, new);
2422 static bool need_remote_flush(u64 old, u64 new)
2424 if (!is_shadow_present_pte(old))
2426 if (!is_shadow_present_pte(new))
2428 if ((old ^ new) & PT64_BASE_ADDR_MASK)
2430 old ^= PT64_NX_MASK;
2431 new ^= PT64_NX_MASK;
2432 return (old & ~new & PT64_PERM_MASK) != 0;
2435 static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, u64 old, u64 new)
2437 if (need_remote_flush(old, new))
2438 kvm_flush_remote_tlbs(vcpu->kvm);
2440 kvm_mmu_flush_tlb(vcpu);
2443 static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu)
2445 u64 *spte = vcpu->arch.last_pte_updated;
2447 return !!(spte && (*spte & shadow_accessed_mask));
2450 static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
2451 const u8 *new, int bytes)
2458 vcpu->arch.update_pte.largepage = 0;
2460 if (bytes != 4 && bytes != 8)
2464 * Assume that the pte write on a page table of the same type
2465 * as the current vcpu paging mode. This is nearly always true
2466 * (might be false while changing modes). Note it is verified later
2470 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2471 if ((bytes == 4) && (gpa % 4 == 0)) {
2472 r = kvm_read_guest(vcpu->kvm, gpa & ~(u64)7, &gpte, 8);
2475 memcpy((void *)&gpte + (gpa % 8), new, 4);
2476 } else if ((bytes == 8) && (gpa % 8 == 0)) {
2477 memcpy((void *)&gpte, new, 8);
2480 if ((bytes == 4) && (gpa % 4 == 0))
2481 memcpy((void *)&gpte, new, 4);
2483 if (!is_present_gpte(gpte))
2485 gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
2487 if (is_large_pte(gpte) && is_largepage_backed(vcpu, gfn)) {
2488 gfn &= ~(KVM_PAGES_PER_HPAGE-1);
2489 vcpu->arch.update_pte.largepage = 1;
2491 vcpu->arch.update_pte.mmu_seq = vcpu->kvm->mmu_notifier_seq;
2493 pfn = gfn_to_pfn(vcpu->kvm, gfn);
2495 if (is_error_pfn(pfn)) {
2496 kvm_release_pfn_clean(pfn);
2499 vcpu->arch.update_pte.gfn = gfn;
2500 vcpu->arch.update_pte.pfn = pfn;
2503 static void kvm_mmu_access_page(struct kvm_vcpu *vcpu, gfn_t gfn)
2505 u64 *spte = vcpu->arch.last_pte_updated;
2508 && vcpu->arch.last_pte_gfn == gfn
2509 && shadow_accessed_mask
2510 && !(*spte & shadow_accessed_mask)
2511 && is_shadow_present_pte(*spte))
2512 set_bit(PT_ACCESSED_SHIFT, (unsigned long *)spte);
2515 void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa,
2516 const u8 *new, int bytes,
2517 bool guest_initiated)
2519 gfn_t gfn = gpa >> PAGE_SHIFT;
2520 struct kvm_mmu_page *sp;
2521 struct hlist_node *node, *n;
2522 struct hlist_head *bucket;
2526 unsigned offset = offset_in_page(gpa);
2528 unsigned page_offset;
2529 unsigned misaligned;
2536 pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes);
2537 mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes);
2538 spin_lock(&vcpu->kvm->mmu_lock);
2539 kvm_mmu_access_page(vcpu, gfn);
2540 kvm_mmu_free_some_pages(vcpu);
2541 ++vcpu->kvm->stat.mmu_pte_write;
2542 kvm_mmu_audit(vcpu, "pre pte write");
2543 if (guest_initiated) {
2544 if (gfn == vcpu->arch.last_pt_write_gfn
2545 && !last_updated_pte_accessed(vcpu)) {
2546 ++vcpu->arch.last_pt_write_count;
2547 if (vcpu->arch.last_pt_write_count >= 3)
2550 vcpu->arch.last_pt_write_gfn = gfn;
2551 vcpu->arch.last_pt_write_count = 1;
2552 vcpu->arch.last_pte_updated = NULL;
2555 index = kvm_page_table_hashfn(gfn);
2556 bucket = &vcpu->kvm->arch.mmu_page_hash[index];
2557 hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) {
2558 if (sp->gfn != gfn || sp->role.direct || sp->role.invalid)
2560 pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8;
2561 misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1);
2562 misaligned |= bytes < 4;
2563 if (misaligned || flooded) {
2565 * Misaligned accesses are too much trouble to fix
2566 * up; also, they usually indicate a page is not used
2569 * If we're seeing too many writes to a page,
2570 * it may no longer be a page table, or we may be
2571 * forking, in which case it is better to unmap the
2574 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2575 gpa, bytes, sp->role.word);
2576 if (kvm_mmu_zap_page(vcpu->kvm, sp))
2578 ++vcpu->kvm->stat.mmu_flooded;
2581 page_offset = offset;
2582 level = sp->role.level;
2584 if (sp->role.glevels == PT32_ROOT_LEVEL) {
2585 page_offset <<= 1; /* 32->64 */
2587 * A 32-bit pde maps 4MB while the shadow pdes map
2588 * only 2MB. So we need to double the offset again
2589 * and zap two pdes instead of one.
2591 if (level == PT32_ROOT_LEVEL) {
2592 page_offset &= ~7; /* kill rounding error */
2596 quadrant = page_offset >> PAGE_SHIFT;
2597 page_offset &= ~PAGE_MASK;
2598 if (quadrant != sp->role.quadrant)
2601 spte = &sp->spt[page_offset / sizeof(*spte)];
2602 if ((gpa & (pte_size - 1)) || (bytes < pte_size)) {
2604 r = kvm_read_guest_atomic(vcpu->kvm,
2605 gpa & ~(u64)(pte_size - 1),
2607 new = (const void *)&gentry;
2613 mmu_pte_write_zap_pte(vcpu, sp, spte);
2615 mmu_pte_write_new_pte(vcpu, sp, spte, new);
2616 mmu_pte_write_flush_tlb(vcpu, entry, *spte);
2620 kvm_mmu_audit(vcpu, "post pte write");
2621 spin_unlock(&vcpu->kvm->mmu_lock);
2622 if (!is_error_pfn(vcpu->arch.update_pte.pfn)) {
2623 kvm_release_pfn_clean(vcpu->arch.update_pte.pfn);
2624 vcpu->arch.update_pte.pfn = bad_pfn;
2628 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva)
2633 gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva);
2635 spin_lock(&vcpu->kvm->mmu_lock);
2636 r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT);
2637 spin_unlock(&vcpu->kvm->mmu_lock);
2640 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt);
2642 void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
2644 while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) {
2645 struct kvm_mmu_page *sp;
2647 sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev,
2648 struct kvm_mmu_page, link);
2649 kvm_mmu_zap_page(vcpu->kvm, sp);
2650 ++vcpu->kvm->stat.mmu_recycled;
2654 int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code)
2657 enum emulation_result er;
2659 r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code);
2668 r = mmu_topup_memory_caches(vcpu);
2672 er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0);
2677 case EMULATE_DO_MMIO:
2678 ++vcpu->stat.mmio_exits;
2681 vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
2682 vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
2690 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault);
2692 void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
2694 vcpu->arch.mmu.invlpg(vcpu, gva);
2695 kvm_mmu_flush_tlb(vcpu);
2696 ++vcpu->stat.invlpg;
2698 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
2700 void kvm_enable_tdp(void)
2704 EXPORT_SYMBOL_GPL(kvm_enable_tdp);
2706 void kvm_disable_tdp(void)
2708 tdp_enabled = false;
2710 EXPORT_SYMBOL_GPL(kvm_disable_tdp);
2712 static void free_mmu_pages(struct kvm_vcpu *vcpu)
2714 free_page((unsigned long)vcpu->arch.mmu.pae_root);
2717 static int alloc_mmu_pages(struct kvm_vcpu *vcpu)
2724 if (vcpu->kvm->arch.n_requested_mmu_pages)
2725 vcpu->kvm->arch.n_free_mmu_pages =
2726 vcpu->kvm->arch.n_requested_mmu_pages;
2728 vcpu->kvm->arch.n_free_mmu_pages =
2729 vcpu->kvm->arch.n_alloc_mmu_pages;
2731 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2732 * Therefore we need to allocate shadow page tables in the first
2733 * 4GB of memory, which happens to fit the DMA32 zone.
2735 page = alloc_page(GFP_KERNEL | __GFP_DMA32);
2738 vcpu->arch.mmu.pae_root = page_address(page);
2739 for (i = 0; i < 4; ++i)
2740 vcpu->arch.mmu.pae_root[i] = INVALID_PAGE;
2745 free_mmu_pages(vcpu);
2749 int kvm_mmu_create(struct kvm_vcpu *vcpu)
2752 ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
2754 return alloc_mmu_pages(vcpu);
2757 int kvm_mmu_setup(struct kvm_vcpu *vcpu)
2760 ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa));
2762 return init_kvm_mmu(vcpu);
2765 void kvm_mmu_destroy(struct kvm_vcpu *vcpu)
2769 destroy_kvm_mmu(vcpu);
2770 free_mmu_pages(vcpu);
2771 mmu_free_memory_caches(vcpu);
2774 void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot)
2776 struct kvm_mmu_page *sp;
2778 list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) {
2782 if (!test_bit(slot, sp->slot_bitmap))
2786 for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
2788 if (pt[i] & PT_WRITABLE_MASK)
2789 pt[i] &= ~PT_WRITABLE_MASK;
2791 kvm_flush_remote_tlbs(kvm);
2794 void kvm_mmu_zap_all(struct kvm *kvm)
2796 struct kvm_mmu_page *sp, *node;
2798 spin_lock(&kvm->mmu_lock);
2799 list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link)
2800 if (kvm_mmu_zap_page(kvm, sp))
2801 node = container_of(kvm->arch.active_mmu_pages.next,
2802 struct kvm_mmu_page, link);
2803 spin_unlock(&kvm->mmu_lock);
2805 kvm_flush_remote_tlbs(kvm);
2808 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm *kvm)
2810 struct kvm_mmu_page *page;
2812 page = container_of(kvm->arch.active_mmu_pages.prev,
2813 struct kvm_mmu_page, link);
2814 kvm_mmu_zap_page(kvm, page);
2817 static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask)
2820 struct kvm *kvm_freed = NULL;
2821 int cache_count = 0;
2823 spin_lock(&kvm_lock);
2825 list_for_each_entry(kvm, &vm_list, vm_list) {
2828 if (!down_read_trylock(&kvm->slots_lock))
2830 spin_lock(&kvm->mmu_lock);
2831 npages = kvm->arch.n_alloc_mmu_pages -
2832 kvm->arch.n_free_mmu_pages;
2833 cache_count += npages;
2834 if (!kvm_freed && nr_to_scan > 0 && npages > 0) {
2835 kvm_mmu_remove_one_alloc_mmu_page(kvm);
2841 spin_unlock(&kvm->mmu_lock);
2842 up_read(&kvm->slots_lock);
2845 list_move_tail(&kvm_freed->vm_list, &vm_list);
2847 spin_unlock(&kvm_lock);
2852 static struct shrinker mmu_shrinker = {
2853 .shrink = mmu_shrink,
2854 .seeks = DEFAULT_SEEKS * 10,
2857 static void mmu_destroy_caches(void)
2859 if (pte_chain_cache)
2860 kmem_cache_destroy(pte_chain_cache);
2861 if (rmap_desc_cache)
2862 kmem_cache_destroy(rmap_desc_cache);
2863 if (mmu_page_header_cache)
2864 kmem_cache_destroy(mmu_page_header_cache);
2867 void kvm_mmu_module_exit(void)
2869 mmu_destroy_caches();
2870 unregister_shrinker(&mmu_shrinker);
2873 int kvm_mmu_module_init(void)
2875 pte_chain_cache = kmem_cache_create("kvm_pte_chain",
2876 sizeof(struct kvm_pte_chain),
2878 if (!pte_chain_cache)
2880 rmap_desc_cache = kmem_cache_create("kvm_rmap_desc",
2881 sizeof(struct kvm_rmap_desc),
2883 if (!rmap_desc_cache)
2886 mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header",
2887 sizeof(struct kvm_mmu_page),
2889 if (!mmu_page_header_cache)
2892 register_shrinker(&mmu_shrinker);
2897 mmu_destroy_caches();
2902 * Caculate mmu pages needed for kvm.
2904 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm)
2907 unsigned int nr_mmu_pages;
2908 unsigned int nr_pages = 0;
2910 for (i = 0; i < kvm->nmemslots; i++)
2911 nr_pages += kvm->memslots[i].npages;
2913 nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000;
2914 nr_mmu_pages = max(nr_mmu_pages,
2915 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES);
2917 return nr_mmu_pages;
2920 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer *buffer,
2923 if (len > buffer->len)
2928 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer *buffer,
2933 ret = pv_mmu_peek_buffer(buffer, len);
2938 buffer->processed += len;
2942 static int kvm_pv_mmu_write(struct kvm_vcpu *vcpu,
2943 gpa_t addr, gpa_t value)
2948 if (!is_long_mode(vcpu) && !is_pae(vcpu))
2951 r = mmu_topup_memory_caches(vcpu);
2955 if (!emulator_write_phys(vcpu, addr, &value, bytes))
2961 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu *vcpu)
2963 kvm_set_cr3(vcpu, vcpu->arch.cr3);
2967 static int kvm_pv_mmu_release_pt(struct kvm_vcpu *vcpu, gpa_t addr)
2969 spin_lock(&vcpu->kvm->mmu_lock);
2970 mmu_unshadow(vcpu->kvm, addr >> PAGE_SHIFT);
2971 spin_unlock(&vcpu->kvm->mmu_lock);
2975 static int kvm_pv_mmu_op_one(struct kvm_vcpu *vcpu,
2976 struct kvm_pv_mmu_op_buffer *buffer)
2978 struct kvm_mmu_op_header *header;
2980 header = pv_mmu_peek_buffer(buffer, sizeof *header);
2983 switch (header->op) {
2984 case KVM_MMU_OP_WRITE_PTE: {
2985 struct kvm_mmu_op_write_pte *wpte;
2987 wpte = pv_mmu_read_buffer(buffer, sizeof *wpte);
2990 return kvm_pv_mmu_write(vcpu, wpte->pte_phys,
2993 case KVM_MMU_OP_FLUSH_TLB: {
2994 struct kvm_mmu_op_flush_tlb *ftlb;
2996 ftlb = pv_mmu_read_buffer(buffer, sizeof *ftlb);
2999 return kvm_pv_mmu_flush_tlb(vcpu);
3001 case KVM_MMU_OP_RELEASE_PT: {
3002 struct kvm_mmu_op_release_pt *rpt;
3004 rpt = pv_mmu_read_buffer(buffer, sizeof *rpt);
3007 return kvm_pv_mmu_release_pt(vcpu, rpt->pt_phys);
3013 int kvm_pv_mmu_op(struct kvm_vcpu *vcpu, unsigned long bytes,
3014 gpa_t addr, unsigned long *ret)
3017 struct kvm_pv_mmu_op_buffer *buffer = &vcpu->arch.mmu_op_buffer;
3019 buffer->ptr = buffer->buf;
3020 buffer->len = min_t(unsigned long, bytes, sizeof buffer->buf);
3021 buffer->processed = 0;
3023 r = kvm_read_guest(vcpu->kvm, addr, buffer->buf, buffer->len);
3027 while (buffer->len) {
3028 r = kvm_pv_mmu_op_one(vcpu, buffer);
3037 *ret = buffer->processed;
3041 int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4])
3043 struct kvm_shadow_walk_iterator iterator;
3046 spin_lock(&vcpu->kvm->mmu_lock);
3047 for_each_shadow_entry(vcpu, addr, iterator) {
3048 sptes[iterator.level-1] = *iterator.sptep;
3050 if (!is_shadow_present_pte(*iterator.sptep))
3053 spin_unlock(&vcpu->kvm->mmu_lock);
3057 EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy);
3061 static const char *audit_msg;
3063 static gva_t canonicalize(gva_t gva)
3065 #ifdef CONFIG_X86_64
3066 gva = (long long)(gva << 16) >> 16;
3072 typedef void (*inspect_spte_fn) (struct kvm *kvm, struct kvm_mmu_page *sp,
3075 static void __mmu_spte_walk(struct kvm *kvm, struct kvm_mmu_page *sp,
3080 for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
3081 u64 ent = sp->spt[i];
3083 if (is_shadow_present_pte(ent)) {
3084 if (!is_last_spte(ent, sp->role.level)) {
3085 struct kvm_mmu_page *child;
3086 child = page_header(ent & PT64_BASE_ADDR_MASK);
3087 __mmu_spte_walk(kvm, child, fn);
3089 fn(kvm, sp, &sp->spt[i]);
3094 static void mmu_spte_walk(struct kvm_vcpu *vcpu, inspect_spte_fn fn)
3097 struct kvm_mmu_page *sp;
3099 if (!VALID_PAGE(vcpu->arch.mmu.root_hpa))
3101 if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) {
3102 hpa_t root = vcpu->arch.mmu.root_hpa;
3103 sp = page_header(root);
3104 __mmu_spte_walk(vcpu->kvm, sp, fn);
3107 for (i = 0; i < 4; ++i) {
3108 hpa_t root = vcpu->arch.mmu.pae_root[i];
3110 if (root && VALID_PAGE(root)) {
3111 root &= PT64_BASE_ADDR_MASK;
3112 sp = page_header(root);
3113 __mmu_spte_walk(vcpu->kvm, sp, fn);
3119 static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte,
3120 gva_t va, int level)
3122 u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK);
3124 gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1));
3126 for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) {
3129 if (ent == shadow_trap_nonpresent_pte)
3132 va = canonicalize(va);
3133 if (is_shadow_present_pte(ent) && !is_last_spte(ent, level))
3134 audit_mappings_page(vcpu, ent, va, level - 1);
3136 gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va);
3137 gfn_t gfn = gpa >> PAGE_SHIFT;
3138 pfn_t pfn = gfn_to_pfn(vcpu->kvm, gfn);
3139 hpa_t hpa = (hpa_t)pfn << PAGE_SHIFT;
3141 if (is_error_pfn(pfn)) {
3142 kvm_release_pfn_clean(pfn);
3146 if (is_shadow_present_pte(ent)
3147 && (ent & PT64_BASE_ADDR_MASK) != hpa)
3148 printk(KERN_ERR "xx audit error: (%s) levels %d"
3149 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
3150 audit_msg, vcpu->arch.mmu.root_level,
3152 is_shadow_present_pte(ent));
3153 else if (ent == shadow_notrap_nonpresent_pte
3154 && !is_error_hpa(hpa))
3155 printk(KERN_ERR "audit: (%s) notrap shadow,"
3156 " valid guest gva %lx\n", audit_msg, va);
3157 kvm_release_pfn_clean(pfn);
3163 static void audit_mappings(struct kvm_vcpu *vcpu)
3167 if (vcpu->arch.mmu.root_level == 4)
3168 audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4);
3170 for (i = 0; i < 4; ++i)
3171 if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK)
3172 audit_mappings_page(vcpu,
3173 vcpu->arch.mmu.pae_root[i],
3178 static int count_rmaps(struct kvm_vcpu *vcpu)
3183 for (i = 0; i < KVM_MEMORY_SLOTS; ++i) {
3184 struct kvm_memory_slot *m = &vcpu->kvm->memslots[i];
3185 struct kvm_rmap_desc *d;
3187 for (j = 0; j < m->npages; ++j) {
3188 unsigned long *rmapp = &m->rmap[j];
3192 if (!(*rmapp & 1)) {
3196 d = (struct kvm_rmap_desc *)(*rmapp & ~1ul);
3198 for (k = 0; k < RMAP_EXT; ++k)
3210 void inspect_spte_has_rmap(struct kvm *kvm, struct kvm_mmu_page *sp, u64 *sptep)
3212 unsigned long *rmapp;
3213 struct kvm_mmu_page *rev_sp;
3216 if (*sptep & PT_WRITABLE_MASK) {
3217 rev_sp = page_header(__pa(sptep));
3218 gfn = rev_sp->gfns[sptep - rev_sp->spt];
3220 if (!gfn_to_memslot(kvm, gfn)) {
3221 if (!printk_ratelimit())
3223 printk(KERN_ERR "%s: no memslot for gfn %ld\n",
3225 printk(KERN_ERR "%s: index %ld of sp (gfn=%lx)\n",
3226 audit_msg, sptep - rev_sp->spt,
3232 rmapp = gfn_to_rmap(kvm, rev_sp->gfns[sptep - rev_sp->spt],
3233 is_large_pte(*sptep));
3235 if (!printk_ratelimit())
3237 printk(KERN_ERR "%s: no rmap for writable spte %llx\n",
3245 void audit_writable_sptes_have_rmaps(struct kvm_vcpu *vcpu)
3247 mmu_spte_walk(vcpu, inspect_spte_has_rmap);
3250 static void check_writable_mappings_rmap(struct kvm_vcpu *vcpu)
3252 struct kvm_mmu_page *sp;
3255 list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
3258 if (sp->role.level != PT_PAGE_TABLE_LEVEL)
3261 for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
3264 if (!(ent & PT_PRESENT_MASK))
3266 if (!(ent & PT_WRITABLE_MASK))
3268 inspect_spte_has_rmap(vcpu->kvm, sp, &pt[i]);
3274 static void audit_rmap(struct kvm_vcpu *vcpu)
3276 check_writable_mappings_rmap(vcpu);
3280 static void audit_write_protection(struct kvm_vcpu *vcpu)
3282 struct kvm_mmu_page *sp;
3283 struct kvm_memory_slot *slot;
3284 unsigned long *rmapp;
3288 list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) {
3289 if (sp->role.direct)
3294 gfn = unalias_gfn(vcpu->kvm, sp->gfn);
3295 slot = gfn_to_memslot_unaliased(vcpu->kvm, sp->gfn);
3296 rmapp = &slot->rmap[gfn - slot->base_gfn];
3298 spte = rmap_next(vcpu->kvm, rmapp, NULL);
3300 if (*spte & PT_WRITABLE_MASK)
3301 printk(KERN_ERR "%s: (%s) shadow page has "
3302 "writable mappings: gfn %lx role %x\n",
3303 __func__, audit_msg, sp->gfn,
3305 spte = rmap_next(vcpu->kvm, rmapp, spte);
3310 static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg)
3317 audit_write_protection(vcpu);
3318 if (strcmp("pre pte write", audit_msg) != 0)
3319 audit_mappings(vcpu);
3320 audit_writable_sptes_have_rmaps(vcpu);