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.
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>
38 * When setting this variable to true it enables Two-Dimensional-Paging
39 * where the hardware walks 2 page tables:
40 * 1. the guest-virtual to guest-physical
41 * 2. while doing 1. it walks guest-physical to host-physical
42 * If the hardware supports that we don't need to do shadow paging.
44 bool tdp_enabled
= false;
51 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
);
53 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
) {}
58 #define pgprintk(x...) do { if (dbg) printk(x); } while (0)
59 #define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
63 #define pgprintk(x...) do { } while (0)
64 #define rmap_printk(x...) do { } while (0)
68 #if defined(MMU_DEBUG) || defined(AUDIT)
73 #define ASSERT(x) do { } while (0)
77 printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
78 __FILE__, __LINE__, #x); \
82 #define PT64_PT_BITS 9
83 #define PT64_ENT_PER_PAGE (1 << PT64_PT_BITS)
84 #define PT32_PT_BITS 10
85 #define PT32_ENT_PER_PAGE (1 << PT32_PT_BITS)
87 #define PT_WRITABLE_SHIFT 1
89 #define PT_PRESENT_MASK (1ULL << 0)
90 #define PT_WRITABLE_MASK (1ULL << PT_WRITABLE_SHIFT)
91 #define PT_USER_MASK (1ULL << 2)
92 #define PT_PWT_MASK (1ULL << 3)
93 #define PT_PCD_MASK (1ULL << 4)
94 #define PT_ACCESSED_MASK (1ULL << 5)
95 #define PT_DIRTY_MASK (1ULL << 6)
96 #define PT_PAGE_SIZE_MASK (1ULL << 7)
97 #define PT_PAT_MASK (1ULL << 7)
98 #define PT_GLOBAL_MASK (1ULL << 8)
99 #define PT64_NX_SHIFT 63
100 #define PT64_NX_MASK (1ULL << PT64_NX_SHIFT)
102 #define PT_PAT_SHIFT 7
103 #define PT_DIR_PAT_SHIFT 12
104 #define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT)
106 #define PT32_DIR_PSE36_SIZE 4
107 #define PT32_DIR_PSE36_SHIFT 13
108 #define PT32_DIR_PSE36_MASK \
109 (((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT)
112 #define PT_FIRST_AVAIL_BITS_SHIFT 9
113 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
115 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
117 #define PT64_LEVEL_BITS 9
119 #define PT64_LEVEL_SHIFT(level) \
120 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
122 #define PT64_LEVEL_MASK(level) \
123 (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
125 #define PT64_INDEX(address, level)\
126 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
129 #define PT32_LEVEL_BITS 10
131 #define PT32_LEVEL_SHIFT(level) \
132 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
134 #define PT32_LEVEL_MASK(level) \
135 (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
137 #define PT32_INDEX(address, level)\
138 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
141 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
142 #define PT64_DIR_BASE_ADDR_MASK \
143 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
145 #define PT32_BASE_ADDR_MASK PAGE_MASK
146 #define PT32_DIR_BASE_ADDR_MASK \
147 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
149 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
152 #define PFERR_PRESENT_MASK (1U << 0)
153 #define PFERR_WRITE_MASK (1U << 1)
154 #define PFERR_USER_MASK (1U << 2)
155 #define PFERR_FETCH_MASK (1U << 4)
157 #define PT64_ROOT_LEVEL 4
158 #define PT32_ROOT_LEVEL 2
159 #define PT32E_ROOT_LEVEL 3
161 #define PT_DIRECTORY_LEVEL 2
162 #define PT_PAGE_TABLE_LEVEL 1
166 #define ACC_EXEC_MASK 1
167 #define ACC_WRITE_MASK PT_WRITABLE_MASK
168 #define ACC_USER_MASK PT_USER_MASK
169 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
171 struct kvm_pv_mmu_op_buffer
{
175 char buf
[512] __aligned(sizeof(long));
178 struct kvm_rmap_desc
{
179 u64
*shadow_ptes
[RMAP_EXT
];
180 struct kvm_rmap_desc
*more
;
183 static struct kmem_cache
*pte_chain_cache
;
184 static struct kmem_cache
*rmap_desc_cache
;
185 static struct kmem_cache
*mmu_page_header_cache
;
187 static u64 __read_mostly shadow_trap_nonpresent_pte
;
188 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
190 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
192 shadow_trap_nonpresent_pte
= trap_pte
;
193 shadow_notrap_nonpresent_pte
= notrap_pte
;
195 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
197 static int is_write_protection(struct kvm_vcpu
*vcpu
)
199 return vcpu
->arch
.cr0
& X86_CR0_WP
;
202 static int is_cpuid_PSE36(void)
207 static int is_nx(struct kvm_vcpu
*vcpu
)
209 return vcpu
->arch
.shadow_efer
& EFER_NX
;
212 static int is_present_pte(unsigned long pte
)
214 return pte
& PT_PRESENT_MASK
;
217 static int is_shadow_present_pte(u64 pte
)
219 return pte
!= shadow_trap_nonpresent_pte
220 && pte
!= shadow_notrap_nonpresent_pte
;
223 static int is_large_pte(u64 pte
)
225 return pte
& PT_PAGE_SIZE_MASK
;
228 static int is_writeble_pte(unsigned long pte
)
230 return pte
& PT_WRITABLE_MASK
;
233 static int is_dirty_pte(unsigned long pte
)
235 return pte
& PT_DIRTY_MASK
;
238 static int is_rmap_pte(u64 pte
)
240 return is_shadow_present_pte(pte
);
243 static struct page
*spte_to_page(u64 pte
)
245 hfn_t hfn
= (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
247 return pfn_to_page(hfn
);
250 static gfn_t
pse36_gfn_delta(u32 gpte
)
252 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
254 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
257 static void set_shadow_pte(u64
*sptep
, u64 spte
)
260 set_64bit((unsigned long *)sptep
, spte
);
262 set_64bit((unsigned long long *)sptep
, spte
);
266 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
267 struct kmem_cache
*base_cache
, int min
)
271 if (cache
->nobjs
>= min
)
273 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
274 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
277 cache
->objects
[cache
->nobjs
++] = obj
;
282 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
285 kfree(mc
->objects
[--mc
->nobjs
]);
288 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
293 if (cache
->nobjs
>= min
)
295 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
296 page
= alloc_page(GFP_KERNEL
);
299 set_page_private(page
, 0);
300 cache
->objects
[cache
->nobjs
++] = page_address(page
);
305 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
308 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
311 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
315 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
319 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
323 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
326 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
327 mmu_page_header_cache
, 4);
332 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
334 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
335 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
336 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
337 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
340 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
346 p
= mc
->objects
[--mc
->nobjs
];
351 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
353 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
354 sizeof(struct kvm_pte_chain
));
357 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
362 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
364 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
365 sizeof(struct kvm_rmap_desc
));
368 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
374 * Return the pointer to the largepage write count for a given
375 * gfn, handling slots that are not large page aligned.
377 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
381 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
382 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
383 return &slot
->lpage_info
[idx
].write_count
;
386 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
390 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
392 WARN_ON(*write_count
> KVM_PAGES_PER_HPAGE
);
395 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
399 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
401 WARN_ON(*write_count
< 0);
404 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
406 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
410 largepage_idx
= slot_largepage_idx(gfn
, slot
);
411 return *largepage_idx
;
417 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
419 struct vm_area_struct
*vma
;
422 addr
= gfn_to_hva(kvm
, gfn
);
423 if (kvm_is_error_hva(addr
))
426 vma
= find_vma(current
->mm
, addr
);
427 if (vma
&& is_vm_hugetlb_page(vma
))
433 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
435 struct kvm_memory_slot
*slot
;
437 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
440 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
443 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
444 if (slot
&& slot
->dirty_bitmap
)
451 * Take gfn and return the reverse mapping to it.
452 * Note: gfn must be unaliased before this function get called
455 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
457 struct kvm_memory_slot
*slot
;
460 slot
= gfn_to_memslot(kvm
, gfn
);
462 return &slot
->rmap
[gfn
- slot
->base_gfn
];
464 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
465 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
467 return &slot
->lpage_info
[idx
].rmap_pde
;
471 * Reverse mapping data structures:
473 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
474 * that points to page_address(page).
476 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
477 * containing more mappings.
479 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
481 struct kvm_mmu_page
*sp
;
482 struct kvm_rmap_desc
*desc
;
483 unsigned long *rmapp
;
486 if (!is_rmap_pte(*spte
))
488 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
489 sp
= page_header(__pa(spte
));
490 sp
->gfns
[spte
- sp
->spt
] = gfn
;
491 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
493 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
494 *rmapp
= (unsigned long)spte
;
495 } else if (!(*rmapp
& 1)) {
496 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
497 desc
= mmu_alloc_rmap_desc(vcpu
);
498 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
499 desc
->shadow_ptes
[1] = spte
;
500 *rmapp
= (unsigned long)desc
| 1;
502 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
503 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
504 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
506 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
507 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
510 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
512 desc
->shadow_ptes
[i
] = spte
;
516 static void rmap_desc_remove_entry(unsigned long *rmapp
,
517 struct kvm_rmap_desc
*desc
,
519 struct kvm_rmap_desc
*prev_desc
)
523 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
525 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
526 desc
->shadow_ptes
[j
] = NULL
;
529 if (!prev_desc
&& !desc
->more
)
530 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
533 prev_desc
->more
= desc
->more
;
535 *rmapp
= (unsigned long)desc
->more
| 1;
536 mmu_free_rmap_desc(desc
);
539 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
541 struct kvm_rmap_desc
*desc
;
542 struct kvm_rmap_desc
*prev_desc
;
543 struct kvm_mmu_page
*sp
;
545 unsigned long *rmapp
;
548 if (!is_rmap_pte(*spte
))
550 sp
= page_header(__pa(spte
));
551 page
= spte_to_page(*spte
);
552 mark_page_accessed(page
);
553 if (is_writeble_pte(*spte
))
554 kvm_release_page_dirty(page
);
556 kvm_release_page_clean(page
);
557 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
559 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
561 } else if (!(*rmapp
& 1)) {
562 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
563 if ((u64
*)*rmapp
!= spte
) {
564 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
570 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
571 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
574 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
575 if (desc
->shadow_ptes
[i
] == spte
) {
576 rmap_desc_remove_entry(rmapp
,
588 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
590 struct kvm_rmap_desc
*desc
;
591 struct kvm_rmap_desc
*prev_desc
;
597 else if (!(*rmapp
& 1)) {
599 return (u64
*)*rmapp
;
602 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
606 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
607 if (prev_spte
== spte
)
608 return desc
->shadow_ptes
[i
];
609 prev_spte
= desc
->shadow_ptes
[i
];
616 static void rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
618 unsigned long *rmapp
;
620 int write_protected
= 0;
622 gfn
= unalias_gfn(kvm
, gfn
);
623 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
625 spte
= rmap_next(kvm
, rmapp
, NULL
);
628 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
629 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
630 if (is_writeble_pte(*spte
)) {
631 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
634 spte
= rmap_next(kvm
, rmapp
, spte
);
636 if (write_protected
) {
639 spte
= rmap_next(kvm
, rmapp
, NULL
);
640 page
= spte_to_page(*spte
);
644 /* check for huge page mappings */
645 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
646 spte
= rmap_next(kvm
, rmapp
, NULL
);
649 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
650 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
651 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
652 if (is_writeble_pte(*spte
)) {
653 rmap_remove(kvm
, spte
);
655 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
658 spte
= rmap_next(kvm
, rmapp
, spte
);
662 kvm_flush_remote_tlbs(kvm
);
664 account_shadowed(kvm
, gfn
);
668 static int is_empty_shadow_page(u64
*spt
)
673 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
674 if (*pos
!= shadow_trap_nonpresent_pte
) {
675 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
683 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
685 ASSERT(is_empty_shadow_page(sp
->spt
));
687 __free_page(virt_to_page(sp
->spt
));
688 __free_page(virt_to_page(sp
->gfns
));
690 ++kvm
->arch
.n_free_mmu_pages
;
693 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
695 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
698 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
701 struct kvm_mmu_page
*sp
;
703 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
704 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
705 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
706 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
707 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
708 ASSERT(is_empty_shadow_page(sp
->spt
));
711 sp
->parent_pte
= parent_pte
;
712 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
716 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
717 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
719 struct kvm_pte_chain
*pte_chain
;
720 struct hlist_node
*node
;
725 if (!sp
->multimapped
) {
726 u64
*old
= sp
->parent_pte
;
729 sp
->parent_pte
= parent_pte
;
733 pte_chain
= mmu_alloc_pte_chain(vcpu
);
734 INIT_HLIST_HEAD(&sp
->parent_ptes
);
735 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
736 pte_chain
->parent_ptes
[0] = old
;
738 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
739 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
741 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
742 if (!pte_chain
->parent_ptes
[i
]) {
743 pte_chain
->parent_ptes
[i
] = parent_pte
;
747 pte_chain
= mmu_alloc_pte_chain(vcpu
);
749 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
750 pte_chain
->parent_ptes
[0] = parent_pte
;
753 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
756 struct kvm_pte_chain
*pte_chain
;
757 struct hlist_node
*node
;
760 if (!sp
->multimapped
) {
761 BUG_ON(sp
->parent_pte
!= parent_pte
);
762 sp
->parent_pte
= NULL
;
765 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
766 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
767 if (!pte_chain
->parent_ptes
[i
])
769 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
771 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
772 && pte_chain
->parent_ptes
[i
+ 1]) {
773 pte_chain
->parent_ptes
[i
]
774 = pte_chain
->parent_ptes
[i
+ 1];
777 pte_chain
->parent_ptes
[i
] = NULL
;
779 hlist_del(&pte_chain
->link
);
780 mmu_free_pte_chain(pte_chain
);
781 if (hlist_empty(&sp
->parent_ptes
)) {
783 sp
->parent_pte
= NULL
;
791 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
794 struct hlist_head
*bucket
;
795 struct kvm_mmu_page
*sp
;
796 struct hlist_node
*node
;
798 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
799 index
= kvm_page_table_hashfn(gfn
);
800 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
801 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
802 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
803 && !sp
->role
.invalid
) {
804 pgprintk("%s: found role %x\n",
805 __func__
, sp
->role
.word
);
811 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
819 union kvm_mmu_page_role role
;
822 struct hlist_head
*bucket
;
823 struct kvm_mmu_page
*sp
;
824 struct hlist_node
*node
;
827 role
.glevels
= vcpu
->arch
.mmu
.root_level
;
829 role
.metaphysical
= metaphysical
;
830 role
.access
= access
;
831 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
832 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
833 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
834 role
.quadrant
= quadrant
;
836 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
838 index
= kvm_page_table_hashfn(gfn
);
839 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
840 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
841 if (sp
->gfn
== gfn
&& sp
->role
.word
== role
.word
) {
842 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
843 pgprintk("%s: found\n", __func__
);
846 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
847 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
850 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
853 hlist_add_head(&sp
->hash_link
, bucket
);
854 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
856 rmap_write_protect(vcpu
->kvm
, gfn
);
860 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
861 struct kvm_mmu_page
*sp
)
869 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
870 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
871 if (is_shadow_present_pte(pt
[i
]))
872 rmap_remove(kvm
, &pt
[i
]);
873 pt
[i
] = shadow_trap_nonpresent_pte
;
875 kvm_flush_remote_tlbs(kvm
);
879 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
882 if (is_shadow_present_pte(ent
)) {
883 if (!is_large_pte(ent
)) {
884 ent
&= PT64_BASE_ADDR_MASK
;
885 mmu_page_remove_parent_pte(page_header(ent
),
889 rmap_remove(kvm
, &pt
[i
]);
892 pt
[i
] = shadow_trap_nonpresent_pte
;
894 kvm_flush_remote_tlbs(kvm
);
897 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
899 mmu_page_remove_parent_pte(sp
, parent_pte
);
902 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
906 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
908 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
911 static void kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
915 ++kvm
->stat
.mmu_shadow_zapped
;
916 while (sp
->multimapped
|| sp
->parent_pte
) {
917 if (!sp
->multimapped
)
918 parent_pte
= sp
->parent_pte
;
920 struct kvm_pte_chain
*chain
;
922 chain
= container_of(sp
->parent_ptes
.first
,
923 struct kvm_pte_chain
, link
);
924 parent_pte
= chain
->parent_ptes
[0];
927 kvm_mmu_put_page(sp
, parent_pte
);
928 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
930 kvm_mmu_page_unlink_children(kvm
, sp
);
931 if (!sp
->root_count
) {
932 if (!sp
->role
.metaphysical
)
933 unaccount_shadowed(kvm
, sp
->gfn
);
934 hlist_del(&sp
->hash_link
);
935 kvm_mmu_free_page(kvm
, sp
);
937 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
938 sp
->role
.invalid
= 1;
939 kvm_reload_remote_mmus(kvm
);
941 kvm_mmu_reset_last_pte_updated(kvm
);
945 * Changing the number of mmu pages allocated to the vm
946 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
948 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
951 * If we set the number of mmu pages to be smaller be than the
952 * number of actived pages , we must to free some mmu pages before we
956 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
958 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
959 - kvm
->arch
.n_free_mmu_pages
;
961 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
962 struct kvm_mmu_page
*page
;
964 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
965 struct kvm_mmu_page
, link
);
966 kvm_mmu_zap_page(kvm
, page
);
969 kvm
->arch
.n_free_mmu_pages
= 0;
972 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
973 - kvm
->arch
.n_alloc_mmu_pages
;
975 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
978 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
981 struct hlist_head
*bucket
;
982 struct kvm_mmu_page
*sp
;
983 struct hlist_node
*node
, *n
;
986 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
988 index
= kvm_page_table_hashfn(gfn
);
989 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
990 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
991 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
992 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
994 kvm_mmu_zap_page(kvm
, sp
);
1000 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1002 struct kvm_mmu_page
*sp
;
1004 while ((sp
= kvm_mmu_lookup_page(kvm
, gfn
)) != NULL
) {
1005 pgprintk("%s: zap %lx %x\n", __func__
, gfn
, sp
->role
.word
);
1006 kvm_mmu_zap_page(kvm
, sp
);
1010 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1012 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1013 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1015 __set_bit(slot
, &sp
->slot_bitmap
);
1018 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1022 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1024 if (gpa
== UNMAPPED_GVA
)
1027 down_read(¤t
->mm
->mmap_sem
);
1028 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1029 up_read(¤t
->mm
->mmap_sem
);
1034 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1035 unsigned pt_access
, unsigned pte_access
,
1036 int user_fault
, int write_fault
, int dirty
,
1037 int *ptwrite
, int largepage
, gfn_t gfn
,
1038 struct page
*page
, bool speculative
)
1041 int was_rmapped
= 0;
1042 int was_writeble
= is_writeble_pte(*shadow_pte
);
1044 pgprintk("%s: spte %llx access %x write_fault %d"
1045 " user_fault %d gfn %lx\n",
1046 __func__
, *shadow_pte
, pt_access
,
1047 write_fault
, user_fault
, gfn
);
1049 if (is_rmap_pte(*shadow_pte
)) {
1051 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1052 * the parent of the now unreachable PTE.
1054 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1055 struct kvm_mmu_page
*child
;
1056 u64 pte
= *shadow_pte
;
1058 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1059 mmu_page_remove_parent_pte(child
, shadow_pte
);
1060 } else if (page
!= spte_to_page(*shadow_pte
)) {
1061 pgprintk("hfn old %lx new %lx\n",
1062 page_to_pfn(spte_to_page(*shadow_pte
)),
1064 rmap_remove(vcpu
->kvm
, shadow_pte
);
1067 was_rmapped
= is_large_pte(*shadow_pte
);
1074 * We don't set the accessed bit, since we sometimes want to see
1075 * whether the guest actually used the pte (in order to detect
1078 spte
= PT_PRESENT_MASK
| PT_DIRTY_MASK
;
1080 pte_access
|= PT_ACCESSED_MASK
;
1082 pte_access
&= ~ACC_WRITE_MASK
;
1083 if (!(pte_access
& ACC_EXEC_MASK
))
1084 spte
|= PT64_NX_MASK
;
1086 spte
|= PT_PRESENT_MASK
;
1087 if (pte_access
& ACC_USER_MASK
)
1088 spte
|= PT_USER_MASK
;
1090 spte
|= PT_PAGE_SIZE_MASK
;
1092 spte
|= page_to_phys(page
);
1094 if ((pte_access
& ACC_WRITE_MASK
)
1095 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1096 struct kvm_mmu_page
*shadow
;
1098 spte
|= PT_WRITABLE_MASK
;
1100 mmu_unshadow(vcpu
->kvm
, gfn
);
1104 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1106 (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
))) {
1107 pgprintk("%s: found shadow page for %lx, marking ro\n",
1109 pte_access
&= ~ACC_WRITE_MASK
;
1110 if (is_writeble_pte(spte
)) {
1111 spte
&= ~PT_WRITABLE_MASK
;
1112 kvm_x86_ops
->tlb_flush(vcpu
);
1121 if (pte_access
& ACC_WRITE_MASK
)
1122 mark_page_dirty(vcpu
->kvm
, gfn
);
1124 pgprintk("%s: setting spte %llx\n", __func__
, spte
);
1125 pgprintk("instantiating %s PTE (%s) at %d (%llx) addr %llx\n",
1126 (spte
&PT_PAGE_SIZE_MASK
)? "2MB" : "4kB",
1127 (spte
&PT_WRITABLE_MASK
)?"RW":"R", gfn
, spte
, shadow_pte
);
1128 set_shadow_pte(shadow_pte
, spte
);
1129 if (!was_rmapped
&& (spte
& PT_PAGE_SIZE_MASK
)
1130 && (spte
& PT_PRESENT_MASK
))
1131 ++vcpu
->kvm
->stat
.lpages
;
1133 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1135 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1136 if (!is_rmap_pte(*shadow_pte
))
1137 kvm_release_page_clean(page
);
1140 kvm_release_page_dirty(page
);
1142 kvm_release_page_clean(page
);
1144 if (!ptwrite
|| !*ptwrite
)
1145 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1148 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1152 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1153 int largepage
, gfn_t gfn
, struct page
*page
,
1156 hpa_t table_addr
= vcpu
->arch
.mmu
.root_hpa
;
1160 u32 index
= PT64_INDEX(v
, level
);
1163 ASSERT(VALID_PAGE(table_addr
));
1164 table
= __va(table_addr
);
1167 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1168 0, write
, 1, &pt_write
, 0, gfn
, page
, false);
1172 if (largepage
&& level
== 2) {
1173 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1174 0, write
, 1, &pt_write
, 1, gfn
, page
, false);
1178 if (table
[index
] == shadow_trap_nonpresent_pte
) {
1179 struct kvm_mmu_page
*new_table
;
1182 pseudo_gfn
= (v
& PT64_DIR_BASE_ADDR_MASK
)
1184 new_table
= kvm_mmu_get_page(vcpu
, pseudo_gfn
,
1186 1, ACC_ALL
, &table
[index
]);
1188 pgprintk("nonpaging_map: ENOMEM\n");
1189 kvm_release_page_clean(page
);
1193 table
[index
] = __pa(new_table
->spt
) | PT_PRESENT_MASK
1194 | PT_WRITABLE_MASK
| PT_USER_MASK
;
1196 table_addr
= table
[index
] & PT64_BASE_ADDR_MASK
;
1200 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1207 down_read(&vcpu
->kvm
->slots_lock
);
1209 down_read(¤t
->mm
->mmap_sem
);
1210 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1211 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1215 page
= gfn_to_page(vcpu
->kvm
, gfn
);
1216 up_read(¤t
->mm
->mmap_sem
);
1219 if (is_error_page(page
)) {
1220 kvm_release_page_clean(page
);
1221 up_read(&vcpu
->kvm
->slots_lock
);
1225 spin_lock(&vcpu
->kvm
->mmu_lock
);
1226 kvm_mmu_free_some_pages(vcpu
);
1227 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, page
,
1229 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1231 up_read(&vcpu
->kvm
->slots_lock
);
1237 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
1238 struct kvm_mmu_page
*sp
)
1242 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1243 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
1246 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1249 struct kvm_mmu_page
*sp
;
1251 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1253 spin_lock(&vcpu
->kvm
->mmu_lock
);
1254 #ifdef CONFIG_X86_64
1255 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1256 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1258 sp
= page_header(root
);
1260 if (!sp
->root_count
&& sp
->role
.invalid
)
1261 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1262 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1263 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1267 for (i
= 0; i
< 4; ++i
) {
1268 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1271 root
&= PT64_BASE_ADDR_MASK
;
1272 sp
= page_header(root
);
1274 if (!sp
->root_count
&& sp
->role
.invalid
)
1275 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1277 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1279 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1280 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1283 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1287 struct kvm_mmu_page
*sp
;
1288 int metaphysical
= 0;
1290 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1292 #ifdef CONFIG_X86_64
1293 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1294 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1296 ASSERT(!VALID_PAGE(root
));
1299 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1300 PT64_ROOT_LEVEL
, metaphysical
,
1302 root
= __pa(sp
->spt
);
1304 vcpu
->arch
.mmu
.root_hpa
= root
;
1308 metaphysical
= !is_paging(vcpu
);
1311 for (i
= 0; i
< 4; ++i
) {
1312 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1314 ASSERT(!VALID_PAGE(root
));
1315 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1316 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1317 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1320 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1321 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1323 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1324 PT32_ROOT_LEVEL
, metaphysical
,
1326 root
= __pa(sp
->spt
);
1328 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1330 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1333 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
1338 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
1344 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
1345 r
= mmu_topup_memory_caches(vcpu
);
1350 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1352 gfn
= gva
>> PAGE_SHIFT
;
1354 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
1355 error_code
& PFERR_WRITE_MASK
, gfn
);
1358 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
1364 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1367 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1369 r
= mmu_topup_memory_caches(vcpu
);
1373 down_read(¤t
->mm
->mmap_sem
);
1374 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1375 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1378 page
= gfn_to_page(vcpu
->kvm
, gfn
);
1379 if (is_error_page(page
)) {
1380 kvm_release_page_clean(page
);
1381 up_read(¤t
->mm
->mmap_sem
);
1384 spin_lock(&vcpu
->kvm
->mmu_lock
);
1385 kvm_mmu_free_some_pages(vcpu
);
1386 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
1387 largepage
, gfn
, page
, TDP_ROOT_LEVEL
);
1388 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1389 up_read(¤t
->mm
->mmap_sem
);
1394 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
1396 mmu_free_roots(vcpu
);
1399 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
1401 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1403 context
->new_cr3
= nonpaging_new_cr3
;
1404 context
->page_fault
= nonpaging_page_fault
;
1405 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1406 context
->free
= nonpaging_free
;
1407 context
->prefetch_page
= nonpaging_prefetch_page
;
1408 context
->root_level
= 0;
1409 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1410 context
->root_hpa
= INVALID_PAGE
;
1414 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
1416 ++vcpu
->stat
.tlb_flush
;
1417 kvm_x86_ops
->tlb_flush(vcpu
);
1420 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
1422 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
1423 mmu_free_roots(vcpu
);
1426 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
1430 kvm_inject_page_fault(vcpu
, addr
, err_code
);
1433 static void paging_free(struct kvm_vcpu
*vcpu
)
1435 nonpaging_free(vcpu
);
1439 #include "paging_tmpl.h"
1443 #include "paging_tmpl.h"
1446 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
1448 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1450 ASSERT(is_pae(vcpu
));
1451 context
->new_cr3
= paging_new_cr3
;
1452 context
->page_fault
= paging64_page_fault
;
1453 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1454 context
->prefetch_page
= paging64_prefetch_page
;
1455 context
->free
= paging_free
;
1456 context
->root_level
= level
;
1457 context
->shadow_root_level
= level
;
1458 context
->root_hpa
= INVALID_PAGE
;
1462 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
1464 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
1467 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
1469 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1471 context
->new_cr3
= paging_new_cr3
;
1472 context
->page_fault
= paging32_page_fault
;
1473 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1474 context
->free
= paging_free
;
1475 context
->prefetch_page
= paging32_prefetch_page
;
1476 context
->root_level
= PT32_ROOT_LEVEL
;
1477 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1478 context
->root_hpa
= INVALID_PAGE
;
1482 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
1484 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
1487 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
1489 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1491 context
->new_cr3
= nonpaging_new_cr3
;
1492 context
->page_fault
= tdp_page_fault
;
1493 context
->free
= nonpaging_free
;
1494 context
->prefetch_page
= nonpaging_prefetch_page
;
1495 context
->shadow_root_level
= TDP_ROOT_LEVEL
;
1496 context
->root_hpa
= INVALID_PAGE
;
1498 if (!is_paging(vcpu
)) {
1499 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1500 context
->root_level
= 0;
1501 } else if (is_long_mode(vcpu
)) {
1502 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1503 context
->root_level
= PT64_ROOT_LEVEL
;
1504 } else if (is_pae(vcpu
)) {
1505 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1506 context
->root_level
= PT32E_ROOT_LEVEL
;
1508 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1509 context
->root_level
= PT32_ROOT_LEVEL
;
1515 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
1518 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1520 if (!is_paging(vcpu
))
1521 return nonpaging_init_context(vcpu
);
1522 else if (is_long_mode(vcpu
))
1523 return paging64_init_context(vcpu
);
1524 else if (is_pae(vcpu
))
1525 return paging32E_init_context(vcpu
);
1527 return paging32_init_context(vcpu
);
1530 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
1533 return init_kvm_tdp_mmu(vcpu
);
1535 return init_kvm_softmmu(vcpu
);
1538 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
1541 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
1542 vcpu
->arch
.mmu
.free(vcpu
);
1543 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1547 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
1549 destroy_kvm_mmu(vcpu
);
1550 return init_kvm_mmu(vcpu
);
1552 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
1554 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
1558 r
= mmu_topup_memory_caches(vcpu
);
1561 spin_lock(&vcpu
->kvm
->mmu_lock
);
1562 kvm_mmu_free_some_pages(vcpu
);
1563 mmu_alloc_roots(vcpu
);
1564 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1565 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
1566 kvm_mmu_flush_tlb(vcpu
);
1570 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
1572 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
1574 mmu_free_roots(vcpu
);
1577 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
1578 struct kvm_mmu_page
*sp
,
1582 struct kvm_mmu_page
*child
;
1585 if (is_shadow_present_pte(pte
)) {
1586 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
1588 rmap_remove(vcpu
->kvm
, spte
);
1590 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1591 mmu_page_remove_parent_pte(child
, spte
);
1594 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
1595 if (is_large_pte(pte
))
1596 --vcpu
->kvm
->stat
.lpages
;
1599 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
1600 struct kvm_mmu_page
*sp
,
1604 if ((sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1605 && !vcpu
->arch
.update_pte
.largepage
) {
1606 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
1610 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
1611 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
1612 paging32_update_pte(vcpu
, sp
, spte
, new);
1614 paging64_update_pte(vcpu
, sp
, spte
, new);
1617 static bool need_remote_flush(u64 old
, u64
new)
1619 if (!is_shadow_present_pte(old
))
1621 if (!is_shadow_present_pte(new))
1623 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
1625 old
^= PT64_NX_MASK
;
1626 new ^= PT64_NX_MASK
;
1627 return (old
& ~new & PT64_PERM_MASK
) != 0;
1630 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
1632 if (need_remote_flush(old
, new))
1633 kvm_flush_remote_tlbs(vcpu
->kvm
);
1635 kvm_mmu_flush_tlb(vcpu
);
1638 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
1640 u64
*spte
= vcpu
->arch
.last_pte_updated
;
1642 return !!(spte
&& (*spte
& PT_ACCESSED_MASK
));
1645 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1646 const u8
*new, int bytes
)
1653 vcpu
->arch
.update_pte
.largepage
= 0;
1655 if (bytes
!= 4 && bytes
!= 8)
1659 * Assume that the pte write on a page table of the same type
1660 * as the current vcpu paging mode. This is nearly always true
1661 * (might be false while changing modes). Note it is verified later
1665 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
1666 if ((bytes
== 4) && (gpa
% 4 == 0)) {
1667 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
1670 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
1671 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
1672 memcpy((void *)&gpte
, new, 8);
1675 if ((bytes
== 4) && (gpa
% 4 == 0))
1676 memcpy((void *)&gpte
, new, 4);
1678 if (!is_present_pte(gpte
))
1680 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1682 down_read(¤t
->mm
->mmap_sem
);
1683 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
1684 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1685 vcpu
->arch
.update_pte
.largepage
= 1;
1687 page
= gfn_to_page(vcpu
->kvm
, gfn
);
1688 up_read(¤t
->mm
->mmap_sem
);
1690 if (is_error_page(page
)) {
1691 kvm_release_page_clean(page
);
1694 vcpu
->arch
.update_pte
.gfn
= gfn
;
1695 vcpu
->arch
.update_pte
.page
= page
;
1698 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1699 const u8
*new, int bytes
)
1701 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1702 struct kvm_mmu_page
*sp
;
1703 struct hlist_node
*node
, *n
;
1704 struct hlist_head
*bucket
;
1708 unsigned offset
= offset_in_page(gpa
);
1710 unsigned page_offset
;
1711 unsigned misaligned
;
1718 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
1719 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
1720 spin_lock(&vcpu
->kvm
->mmu_lock
);
1721 kvm_mmu_free_some_pages(vcpu
);
1722 ++vcpu
->kvm
->stat
.mmu_pte_write
;
1723 kvm_mmu_audit(vcpu
, "pre pte write");
1724 if (gfn
== vcpu
->arch
.last_pt_write_gfn
1725 && !last_updated_pte_accessed(vcpu
)) {
1726 ++vcpu
->arch
.last_pt_write_count
;
1727 if (vcpu
->arch
.last_pt_write_count
>= 3)
1730 vcpu
->arch
.last_pt_write_gfn
= gfn
;
1731 vcpu
->arch
.last_pt_write_count
= 1;
1732 vcpu
->arch
.last_pte_updated
= NULL
;
1734 index
= kvm_page_table_hashfn(gfn
);
1735 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1736 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
1737 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
)
1739 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
1740 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
1741 misaligned
|= bytes
< 4;
1742 if (misaligned
|| flooded
) {
1744 * Misaligned accesses are too much trouble to fix
1745 * up; also, they usually indicate a page is not used
1748 * If we're seeing too many writes to a page,
1749 * it may no longer be a page table, or we may be
1750 * forking, in which case it is better to unmap the
1753 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
1754 gpa
, bytes
, sp
->role
.word
);
1755 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1756 ++vcpu
->kvm
->stat
.mmu_flooded
;
1759 page_offset
= offset
;
1760 level
= sp
->role
.level
;
1762 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
1763 page_offset
<<= 1; /* 32->64 */
1765 * A 32-bit pde maps 4MB while the shadow pdes map
1766 * only 2MB. So we need to double the offset again
1767 * and zap two pdes instead of one.
1769 if (level
== PT32_ROOT_LEVEL
) {
1770 page_offset
&= ~7; /* kill rounding error */
1774 quadrant
= page_offset
>> PAGE_SHIFT
;
1775 page_offset
&= ~PAGE_MASK
;
1776 if (quadrant
!= sp
->role
.quadrant
)
1779 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
1780 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
1782 r
= kvm_read_guest_atomic(vcpu
->kvm
,
1783 gpa
& ~(u64
)(pte_size
- 1),
1785 new = (const void *)&gentry
;
1791 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
1793 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
1794 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
1798 kvm_mmu_audit(vcpu
, "post pte write");
1799 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1800 if (vcpu
->arch
.update_pte
.page
) {
1801 kvm_release_page_clean(vcpu
->arch
.update_pte
.page
);
1802 vcpu
->arch
.update_pte
.page
= NULL
;
1806 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
1811 down_read(&vcpu
->kvm
->slots_lock
);
1812 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1813 up_read(&vcpu
->kvm
->slots_lock
);
1815 spin_lock(&vcpu
->kvm
->mmu_lock
);
1816 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1817 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1821 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
1823 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
1824 struct kvm_mmu_page
*sp
;
1826 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
1827 struct kvm_mmu_page
, link
);
1828 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1829 ++vcpu
->kvm
->stat
.mmu_recycled
;
1833 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
1836 enum emulation_result er
;
1838 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
1847 r
= mmu_topup_memory_caches(vcpu
);
1851 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
1856 case EMULATE_DO_MMIO
:
1857 ++vcpu
->stat
.mmio_exits
;
1860 kvm_report_emulation_failure(vcpu
, "pagetable");
1868 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
1870 void kvm_enable_tdp(void)
1874 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
1876 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
1878 struct kvm_mmu_page
*sp
;
1880 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
1881 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
1882 struct kvm_mmu_page
, link
);
1883 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1885 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
1888 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
1895 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
1896 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1897 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
1899 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1900 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
1902 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
1903 * Therefore we need to allocate shadow page tables in the first
1904 * 4GB of memory, which happens to fit the DMA32 zone.
1906 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
1909 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
1910 for (i
= 0; i
< 4; ++i
)
1911 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1916 free_mmu_pages(vcpu
);
1920 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
1923 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1925 return alloc_mmu_pages(vcpu
);
1928 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
1931 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1933 return init_kvm_mmu(vcpu
);
1936 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
1940 destroy_kvm_mmu(vcpu
);
1941 free_mmu_pages(vcpu
);
1942 mmu_free_memory_caches(vcpu
);
1945 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
1947 struct kvm_mmu_page
*sp
;
1949 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
1953 if (!test_bit(slot
, &sp
->slot_bitmap
))
1957 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1959 if (pt
[i
] & PT_WRITABLE_MASK
)
1960 pt
[i
] &= ~PT_WRITABLE_MASK
;
1964 void kvm_mmu_zap_all(struct kvm
*kvm
)
1966 struct kvm_mmu_page
*sp
, *node
;
1968 spin_lock(&kvm
->mmu_lock
);
1969 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
1970 kvm_mmu_zap_page(kvm
, sp
);
1971 spin_unlock(&kvm
->mmu_lock
);
1973 kvm_flush_remote_tlbs(kvm
);
1976 void kvm_mmu_module_exit(void)
1978 if (pte_chain_cache
)
1979 kmem_cache_destroy(pte_chain_cache
);
1980 if (rmap_desc_cache
)
1981 kmem_cache_destroy(rmap_desc_cache
);
1982 if (mmu_page_header_cache
)
1983 kmem_cache_destroy(mmu_page_header_cache
);
1986 int kvm_mmu_module_init(void)
1988 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
1989 sizeof(struct kvm_pte_chain
),
1991 if (!pte_chain_cache
)
1993 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
1994 sizeof(struct kvm_rmap_desc
),
1996 if (!rmap_desc_cache
)
1999 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2000 sizeof(struct kvm_mmu_page
),
2002 if (!mmu_page_header_cache
)
2008 kvm_mmu_module_exit();
2013 * Caculate mmu pages needed for kvm.
2015 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2018 unsigned int nr_mmu_pages
;
2019 unsigned int nr_pages
= 0;
2021 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2022 nr_pages
+= kvm
->memslots
[i
].npages
;
2024 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2025 nr_mmu_pages
= max(nr_mmu_pages
,
2026 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2028 return nr_mmu_pages
;
2031 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2034 if (len
> buffer
->len
)
2039 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2044 ret
= pv_mmu_peek_buffer(buffer
, len
);
2049 buffer
->processed
+= len
;
2053 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2054 gpa_t addr
, gpa_t value
)
2059 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2062 r
= mmu_topup_memory_caches(vcpu
);
2066 if (!__emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2072 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2074 kvm_x86_ops
->tlb_flush(vcpu
);
2078 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2080 spin_lock(&vcpu
->kvm
->mmu_lock
);
2081 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2082 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2086 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2087 struct kvm_pv_mmu_op_buffer
*buffer
)
2089 struct kvm_mmu_op_header
*header
;
2091 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2094 switch (header
->op
) {
2095 case KVM_MMU_OP_WRITE_PTE
: {
2096 struct kvm_mmu_op_write_pte
*wpte
;
2098 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2101 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2104 case KVM_MMU_OP_FLUSH_TLB
: {
2105 struct kvm_mmu_op_flush_tlb
*ftlb
;
2107 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2110 return kvm_pv_mmu_flush_tlb(vcpu
);
2112 case KVM_MMU_OP_RELEASE_PT
: {
2113 struct kvm_mmu_op_release_pt
*rpt
;
2115 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2118 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2124 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2125 gpa_t addr
, unsigned long *ret
)
2128 struct kvm_pv_mmu_op_buffer buffer
;
2130 down_read(&vcpu
->kvm
->slots_lock
);
2131 down_read(¤t
->mm
->mmap_sem
);
2133 buffer
.ptr
= buffer
.buf
;
2134 buffer
.len
= min_t(unsigned long, bytes
, sizeof buffer
.buf
);
2135 buffer
.processed
= 0;
2137 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
.buf
, buffer
.len
);
2141 while (buffer
.len
) {
2142 r
= kvm_pv_mmu_op_one(vcpu
, &buffer
);
2151 *ret
= buffer
.processed
;
2152 up_read(¤t
->mm
->mmap_sem
);
2153 up_read(&vcpu
->kvm
->slots_lock
);
2159 static const char *audit_msg
;
2161 static gva_t
canonicalize(gva_t gva
)
2163 #ifdef CONFIG_X86_64
2164 gva
= (long long)(gva
<< 16) >> 16;
2169 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2170 gva_t va
, int level
)
2172 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
2174 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
2176 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
2179 if (ent
== shadow_trap_nonpresent_pte
)
2182 va
= canonicalize(va
);
2184 if (ent
== shadow_notrap_nonpresent_pte
)
2185 printk(KERN_ERR
"audit: (%s) nontrapping pte"
2186 " in nonleaf level: levels %d gva %lx"
2187 " level %d pte %llx\n", audit_msg
,
2188 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
2190 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
2192 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
2193 struct page
*page
= gpa_to_page(vcpu
, gpa
);
2194 hpa_t hpa
= page_to_phys(page
);
2196 if (is_shadow_present_pte(ent
)
2197 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
2198 printk(KERN_ERR
"xx audit error: (%s) levels %d"
2199 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
2200 audit_msg
, vcpu
->arch
.mmu
.root_level
,
2202 is_shadow_present_pte(ent
));
2203 else if (ent
== shadow_notrap_nonpresent_pte
2204 && !is_error_hpa(hpa
))
2205 printk(KERN_ERR
"audit: (%s) notrap shadow,"
2206 " valid guest gva %lx\n", audit_msg
, va
);
2207 kvm_release_page_clean(page
);
2213 static void audit_mappings(struct kvm_vcpu
*vcpu
)
2217 if (vcpu
->arch
.mmu
.root_level
== 4)
2218 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
2220 for (i
= 0; i
< 4; ++i
)
2221 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
2222 audit_mappings_page(vcpu
,
2223 vcpu
->arch
.mmu
.pae_root
[i
],
2228 static int count_rmaps(struct kvm_vcpu
*vcpu
)
2233 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
2234 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
2235 struct kvm_rmap_desc
*d
;
2237 for (j
= 0; j
< m
->npages
; ++j
) {
2238 unsigned long *rmapp
= &m
->rmap
[j
];
2242 if (!(*rmapp
& 1)) {
2246 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
2248 for (k
= 0; k
< RMAP_EXT
; ++k
)
2249 if (d
->shadow_ptes
[k
])
2260 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
2263 struct kvm_mmu_page
*sp
;
2266 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2269 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
2272 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
2275 if (!(ent
& PT_PRESENT_MASK
))
2277 if (!(ent
& PT_WRITABLE_MASK
))
2285 static void audit_rmap(struct kvm_vcpu
*vcpu
)
2287 int n_rmap
= count_rmaps(vcpu
);
2288 int n_actual
= count_writable_mappings(vcpu
);
2290 if (n_rmap
!= n_actual
)
2291 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
2292 __func__
, audit_msg
, n_rmap
, n_actual
);
2295 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
2297 struct kvm_mmu_page
*sp
;
2298 struct kvm_memory_slot
*slot
;
2299 unsigned long *rmapp
;
2302 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2303 if (sp
->role
.metaphysical
)
2306 slot
= gfn_to_memslot(vcpu
->kvm
, sp
->gfn
);
2307 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
2308 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
2310 printk(KERN_ERR
"%s: (%s) shadow page has writable"
2311 " mappings: gfn %lx role %x\n",
2312 __func__
, audit_msg
, sp
->gfn
,
2317 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
2324 audit_write_protection(vcpu
);
2325 audit_mappings(vcpu
);