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 PT_FIRST_AVAIL_BITS_SHIFT 9
83 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
85 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
87 #define PT64_LEVEL_BITS 9
89 #define PT64_LEVEL_SHIFT(level) \
90 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
92 #define PT64_LEVEL_MASK(level) \
93 (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
95 #define PT64_INDEX(address, level)\
96 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
99 #define PT32_LEVEL_BITS 10
101 #define PT32_LEVEL_SHIFT(level) \
102 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
104 #define PT32_LEVEL_MASK(level) \
105 (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
107 #define PT32_INDEX(address, level)\
108 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
111 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
112 #define PT64_DIR_BASE_ADDR_MASK \
113 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
115 #define PT32_BASE_ADDR_MASK PAGE_MASK
116 #define PT32_DIR_BASE_ADDR_MASK \
117 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
119 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
122 #define PFERR_PRESENT_MASK (1U << 0)
123 #define PFERR_WRITE_MASK (1U << 1)
124 #define PFERR_USER_MASK (1U << 2)
125 #define PFERR_FETCH_MASK (1U << 4)
127 #define PT_DIRECTORY_LEVEL 2
128 #define PT_PAGE_TABLE_LEVEL 1
132 #define ACC_EXEC_MASK 1
133 #define ACC_WRITE_MASK PT_WRITABLE_MASK
134 #define ACC_USER_MASK PT_USER_MASK
135 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
137 struct kvm_pv_mmu_op_buffer
{
141 char buf
[512] __aligned(sizeof(long));
144 struct kvm_rmap_desc
{
145 u64
*shadow_ptes
[RMAP_EXT
];
146 struct kvm_rmap_desc
*more
;
149 static struct kmem_cache
*pte_chain_cache
;
150 static struct kmem_cache
*rmap_desc_cache
;
151 static struct kmem_cache
*mmu_page_header_cache
;
153 static u64 __read_mostly shadow_trap_nonpresent_pte
;
154 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
156 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
158 shadow_trap_nonpresent_pte
= trap_pte
;
159 shadow_notrap_nonpresent_pte
= notrap_pte
;
161 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
163 static int is_write_protection(struct kvm_vcpu
*vcpu
)
165 return vcpu
->arch
.cr0
& X86_CR0_WP
;
168 static int is_cpuid_PSE36(void)
173 static int is_nx(struct kvm_vcpu
*vcpu
)
175 return vcpu
->arch
.shadow_efer
& EFER_NX
;
178 static int is_present_pte(unsigned long pte
)
180 return pte
& PT_PRESENT_MASK
;
183 static int is_shadow_present_pte(u64 pte
)
185 return pte
!= shadow_trap_nonpresent_pte
186 && pte
!= shadow_notrap_nonpresent_pte
;
189 static int is_large_pte(u64 pte
)
191 return pte
& PT_PAGE_SIZE_MASK
;
194 static int is_writeble_pte(unsigned long pte
)
196 return pte
& PT_WRITABLE_MASK
;
199 static int is_dirty_pte(unsigned long pte
)
201 return pte
& PT_DIRTY_MASK
;
204 static int is_rmap_pte(u64 pte
)
206 return is_shadow_present_pte(pte
);
209 static pfn_t
spte_to_pfn(u64 pte
)
211 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
214 static gfn_t
pse36_gfn_delta(u32 gpte
)
216 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
218 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
221 static void set_shadow_pte(u64
*sptep
, u64 spte
)
224 set_64bit((unsigned long *)sptep
, spte
);
226 set_64bit((unsigned long long *)sptep
, spte
);
230 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
231 struct kmem_cache
*base_cache
, int min
)
235 if (cache
->nobjs
>= min
)
237 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
238 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
241 cache
->objects
[cache
->nobjs
++] = obj
;
246 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
249 kfree(mc
->objects
[--mc
->nobjs
]);
252 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
257 if (cache
->nobjs
>= min
)
259 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
260 page
= alloc_page(GFP_KERNEL
);
263 set_page_private(page
, 0);
264 cache
->objects
[cache
->nobjs
++] = page_address(page
);
269 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
272 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
275 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
279 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
283 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
287 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
290 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
291 mmu_page_header_cache
, 4);
296 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
298 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
299 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
300 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
301 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
304 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
310 p
= mc
->objects
[--mc
->nobjs
];
315 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
317 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
318 sizeof(struct kvm_pte_chain
));
321 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
326 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
328 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
329 sizeof(struct kvm_rmap_desc
));
332 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
338 * Return the pointer to the largepage write count for a given
339 * gfn, handling slots that are not large page aligned.
341 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
345 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
346 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
347 return &slot
->lpage_info
[idx
].write_count
;
350 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
354 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
356 WARN_ON(*write_count
> KVM_PAGES_PER_HPAGE
);
359 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
363 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
365 WARN_ON(*write_count
< 0);
368 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
370 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
374 largepage_idx
= slot_largepage_idx(gfn
, slot
);
375 return *largepage_idx
;
381 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
383 struct vm_area_struct
*vma
;
386 addr
= gfn_to_hva(kvm
, gfn
);
387 if (kvm_is_error_hva(addr
))
390 vma
= find_vma(current
->mm
, addr
);
391 if (vma
&& is_vm_hugetlb_page(vma
))
397 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
399 struct kvm_memory_slot
*slot
;
401 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
404 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
407 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
408 if (slot
&& slot
->dirty_bitmap
)
415 * Take gfn and return the reverse mapping to it.
416 * Note: gfn must be unaliased before this function get called
419 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
421 struct kvm_memory_slot
*slot
;
424 slot
= gfn_to_memslot(kvm
, gfn
);
426 return &slot
->rmap
[gfn
- slot
->base_gfn
];
428 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
429 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
431 return &slot
->lpage_info
[idx
].rmap_pde
;
435 * Reverse mapping data structures:
437 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
438 * that points to page_address(page).
440 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
441 * containing more mappings.
443 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
445 struct kvm_mmu_page
*sp
;
446 struct kvm_rmap_desc
*desc
;
447 unsigned long *rmapp
;
450 if (!is_rmap_pte(*spte
))
452 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
453 sp
= page_header(__pa(spte
));
454 sp
->gfns
[spte
- sp
->spt
] = gfn
;
455 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
457 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
458 *rmapp
= (unsigned long)spte
;
459 } else if (!(*rmapp
& 1)) {
460 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
461 desc
= mmu_alloc_rmap_desc(vcpu
);
462 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
463 desc
->shadow_ptes
[1] = spte
;
464 *rmapp
= (unsigned long)desc
| 1;
466 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
467 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
468 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
470 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
471 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
474 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
476 desc
->shadow_ptes
[i
] = spte
;
480 static void rmap_desc_remove_entry(unsigned long *rmapp
,
481 struct kvm_rmap_desc
*desc
,
483 struct kvm_rmap_desc
*prev_desc
)
487 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
489 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
490 desc
->shadow_ptes
[j
] = NULL
;
493 if (!prev_desc
&& !desc
->more
)
494 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
497 prev_desc
->more
= desc
->more
;
499 *rmapp
= (unsigned long)desc
->more
| 1;
500 mmu_free_rmap_desc(desc
);
503 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
505 struct kvm_rmap_desc
*desc
;
506 struct kvm_rmap_desc
*prev_desc
;
507 struct kvm_mmu_page
*sp
;
509 unsigned long *rmapp
;
512 if (!is_rmap_pte(*spte
))
514 sp
= page_header(__pa(spte
));
515 pfn
= spte_to_pfn(*spte
);
516 if (*spte
& PT_ACCESSED_MASK
)
517 kvm_set_pfn_accessed(pfn
);
518 if (is_writeble_pte(*spte
))
519 kvm_release_pfn_dirty(pfn
);
521 kvm_release_pfn_clean(pfn
);
522 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
524 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
526 } else if (!(*rmapp
& 1)) {
527 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
528 if ((u64
*)*rmapp
!= spte
) {
529 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
535 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
536 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
539 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
540 if (desc
->shadow_ptes
[i
] == spte
) {
541 rmap_desc_remove_entry(rmapp
,
553 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
555 struct kvm_rmap_desc
*desc
;
556 struct kvm_rmap_desc
*prev_desc
;
562 else if (!(*rmapp
& 1)) {
564 return (u64
*)*rmapp
;
567 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
571 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
572 if (prev_spte
== spte
)
573 return desc
->shadow_ptes
[i
];
574 prev_spte
= desc
->shadow_ptes
[i
];
581 static void rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
583 unsigned long *rmapp
;
585 int write_protected
= 0;
587 gfn
= unalias_gfn(kvm
, gfn
);
588 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
590 spte
= rmap_next(kvm
, rmapp
, NULL
);
593 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
594 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
595 if (is_writeble_pte(*spte
)) {
596 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
599 spte
= rmap_next(kvm
, rmapp
, spte
);
601 if (write_protected
) {
604 spte
= rmap_next(kvm
, rmapp
, NULL
);
605 pfn
= spte_to_pfn(*spte
);
606 kvm_set_pfn_dirty(pfn
);
609 /* check for huge page mappings */
610 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
611 spte
= rmap_next(kvm
, rmapp
, NULL
);
614 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
615 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
616 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
617 if (is_writeble_pte(*spte
)) {
618 rmap_remove(kvm
, spte
);
620 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
623 spte
= rmap_next(kvm
, rmapp
, spte
);
627 kvm_flush_remote_tlbs(kvm
);
629 account_shadowed(kvm
, gfn
);
633 static int is_empty_shadow_page(u64
*spt
)
638 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
639 if (*pos
!= shadow_trap_nonpresent_pte
) {
640 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
648 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
650 ASSERT(is_empty_shadow_page(sp
->spt
));
652 __free_page(virt_to_page(sp
->spt
));
653 __free_page(virt_to_page(sp
->gfns
));
655 ++kvm
->arch
.n_free_mmu_pages
;
658 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
660 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
663 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
666 struct kvm_mmu_page
*sp
;
668 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
669 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
670 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
671 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
672 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
673 ASSERT(is_empty_shadow_page(sp
->spt
));
676 sp
->parent_pte
= parent_pte
;
677 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
681 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
682 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
684 struct kvm_pte_chain
*pte_chain
;
685 struct hlist_node
*node
;
690 if (!sp
->multimapped
) {
691 u64
*old
= sp
->parent_pte
;
694 sp
->parent_pte
= parent_pte
;
698 pte_chain
= mmu_alloc_pte_chain(vcpu
);
699 INIT_HLIST_HEAD(&sp
->parent_ptes
);
700 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
701 pte_chain
->parent_ptes
[0] = old
;
703 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
704 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
706 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
707 if (!pte_chain
->parent_ptes
[i
]) {
708 pte_chain
->parent_ptes
[i
] = parent_pte
;
712 pte_chain
= mmu_alloc_pte_chain(vcpu
);
714 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
715 pte_chain
->parent_ptes
[0] = parent_pte
;
718 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
721 struct kvm_pte_chain
*pte_chain
;
722 struct hlist_node
*node
;
725 if (!sp
->multimapped
) {
726 BUG_ON(sp
->parent_pte
!= parent_pte
);
727 sp
->parent_pte
= NULL
;
730 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
731 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
732 if (!pte_chain
->parent_ptes
[i
])
734 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
736 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
737 && pte_chain
->parent_ptes
[i
+ 1]) {
738 pte_chain
->parent_ptes
[i
]
739 = pte_chain
->parent_ptes
[i
+ 1];
742 pte_chain
->parent_ptes
[i
] = NULL
;
744 hlist_del(&pte_chain
->link
);
745 mmu_free_pte_chain(pte_chain
);
746 if (hlist_empty(&sp
->parent_ptes
)) {
748 sp
->parent_pte
= NULL
;
756 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
759 struct hlist_head
*bucket
;
760 struct kvm_mmu_page
*sp
;
761 struct hlist_node
*node
;
763 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
764 index
= kvm_page_table_hashfn(gfn
);
765 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
766 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
767 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
768 && !sp
->role
.invalid
) {
769 pgprintk("%s: found role %x\n",
770 __func__
, sp
->role
.word
);
776 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
784 union kvm_mmu_page_role role
;
787 struct hlist_head
*bucket
;
788 struct kvm_mmu_page
*sp
;
789 struct hlist_node
*node
;
792 role
.glevels
= vcpu
->arch
.mmu
.root_level
;
794 role
.metaphysical
= metaphysical
;
795 role
.access
= access
;
796 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
797 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
798 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
799 role
.quadrant
= quadrant
;
801 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
803 index
= kvm_page_table_hashfn(gfn
);
804 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
805 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
806 if (sp
->gfn
== gfn
&& sp
->role
.word
== role
.word
) {
807 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
808 pgprintk("%s: found\n", __func__
);
811 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
812 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
815 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
818 hlist_add_head(&sp
->hash_link
, bucket
);
820 rmap_write_protect(vcpu
->kvm
, gfn
);
821 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
825 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
826 struct kvm_mmu_page
*sp
)
834 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
835 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
836 if (is_shadow_present_pte(pt
[i
]))
837 rmap_remove(kvm
, &pt
[i
]);
838 pt
[i
] = shadow_trap_nonpresent_pte
;
840 kvm_flush_remote_tlbs(kvm
);
844 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
847 if (is_shadow_present_pte(ent
)) {
848 if (!is_large_pte(ent
)) {
849 ent
&= PT64_BASE_ADDR_MASK
;
850 mmu_page_remove_parent_pte(page_header(ent
),
854 rmap_remove(kvm
, &pt
[i
]);
857 pt
[i
] = shadow_trap_nonpresent_pte
;
859 kvm_flush_remote_tlbs(kvm
);
862 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
864 mmu_page_remove_parent_pte(sp
, parent_pte
);
867 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
871 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
873 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
876 static void kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
880 ++kvm
->stat
.mmu_shadow_zapped
;
881 while (sp
->multimapped
|| sp
->parent_pte
) {
882 if (!sp
->multimapped
)
883 parent_pte
= sp
->parent_pte
;
885 struct kvm_pte_chain
*chain
;
887 chain
= container_of(sp
->parent_ptes
.first
,
888 struct kvm_pte_chain
, link
);
889 parent_pte
= chain
->parent_ptes
[0];
892 kvm_mmu_put_page(sp
, parent_pte
);
893 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
895 kvm_mmu_page_unlink_children(kvm
, sp
);
896 if (!sp
->root_count
) {
897 if (!sp
->role
.metaphysical
)
898 unaccount_shadowed(kvm
, sp
->gfn
);
899 hlist_del(&sp
->hash_link
);
900 kvm_mmu_free_page(kvm
, sp
);
902 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
903 sp
->role
.invalid
= 1;
904 kvm_reload_remote_mmus(kvm
);
906 kvm_mmu_reset_last_pte_updated(kvm
);
910 * Changing the number of mmu pages allocated to the vm
911 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
913 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
916 * If we set the number of mmu pages to be smaller be than the
917 * number of actived pages , we must to free some mmu pages before we
921 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
923 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
924 - kvm
->arch
.n_free_mmu_pages
;
926 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
927 struct kvm_mmu_page
*page
;
929 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
930 struct kvm_mmu_page
, link
);
931 kvm_mmu_zap_page(kvm
, page
);
934 kvm
->arch
.n_free_mmu_pages
= 0;
937 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
938 - kvm
->arch
.n_alloc_mmu_pages
;
940 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
943 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
946 struct hlist_head
*bucket
;
947 struct kvm_mmu_page
*sp
;
948 struct hlist_node
*node
, *n
;
951 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
953 index
= kvm_page_table_hashfn(gfn
);
954 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
955 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
956 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
957 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
959 kvm_mmu_zap_page(kvm
, sp
);
965 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
967 struct kvm_mmu_page
*sp
;
969 while ((sp
= kvm_mmu_lookup_page(kvm
, gfn
)) != NULL
) {
970 pgprintk("%s: zap %lx %x\n", __func__
, gfn
, sp
->role
.word
);
971 kvm_mmu_zap_page(kvm
, sp
);
975 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
977 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
978 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
980 __set_bit(slot
, &sp
->slot_bitmap
);
983 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
987 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
989 if (gpa
== UNMAPPED_GVA
)
992 down_read(¤t
->mm
->mmap_sem
);
993 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
994 up_read(¤t
->mm
->mmap_sem
);
999 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1000 unsigned pt_access
, unsigned pte_access
,
1001 int user_fault
, int write_fault
, int dirty
,
1002 int *ptwrite
, int largepage
, gfn_t gfn
,
1003 pfn_t pfn
, bool speculative
)
1006 int was_rmapped
= 0;
1007 int was_writeble
= is_writeble_pte(*shadow_pte
);
1009 pgprintk("%s: spte %llx access %x write_fault %d"
1010 " user_fault %d gfn %lx\n",
1011 __func__
, *shadow_pte
, pt_access
,
1012 write_fault
, user_fault
, gfn
);
1014 if (is_rmap_pte(*shadow_pte
)) {
1016 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1017 * the parent of the now unreachable PTE.
1019 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1020 struct kvm_mmu_page
*child
;
1021 u64 pte
= *shadow_pte
;
1023 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1024 mmu_page_remove_parent_pte(child
, shadow_pte
);
1025 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1026 pgprintk("hfn old %lx new %lx\n",
1027 spte_to_pfn(*shadow_pte
), pfn
);
1028 rmap_remove(vcpu
->kvm
, shadow_pte
);
1031 was_rmapped
= is_large_pte(*shadow_pte
);
1038 * We don't set the accessed bit, since we sometimes want to see
1039 * whether the guest actually used the pte (in order to detect
1042 spte
= PT_PRESENT_MASK
| PT_DIRTY_MASK
;
1044 pte_access
|= PT_ACCESSED_MASK
;
1046 pte_access
&= ~ACC_WRITE_MASK
;
1047 if (!(pte_access
& ACC_EXEC_MASK
))
1048 spte
|= PT64_NX_MASK
;
1050 spte
|= PT_PRESENT_MASK
;
1051 if (pte_access
& ACC_USER_MASK
)
1052 spte
|= PT_USER_MASK
;
1054 spte
|= PT_PAGE_SIZE_MASK
;
1056 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1058 if ((pte_access
& ACC_WRITE_MASK
)
1059 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1060 struct kvm_mmu_page
*shadow
;
1062 spte
|= PT_WRITABLE_MASK
;
1064 mmu_unshadow(vcpu
->kvm
, gfn
);
1068 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1070 (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
))) {
1071 pgprintk("%s: found shadow page for %lx, marking ro\n",
1073 pte_access
&= ~ACC_WRITE_MASK
;
1074 if (is_writeble_pte(spte
)) {
1075 spte
&= ~PT_WRITABLE_MASK
;
1076 kvm_x86_ops
->tlb_flush(vcpu
);
1085 if (pte_access
& ACC_WRITE_MASK
)
1086 mark_page_dirty(vcpu
->kvm
, gfn
);
1088 pgprintk("%s: setting spte %llx\n", __func__
, spte
);
1089 pgprintk("instantiating %s PTE (%s) at %d (%llx) addr %llx\n",
1090 (spte
&PT_PAGE_SIZE_MASK
)? "2MB" : "4kB",
1091 (spte
&PT_WRITABLE_MASK
)?"RW":"R", gfn
, spte
, shadow_pte
);
1092 set_shadow_pte(shadow_pte
, spte
);
1093 if (!was_rmapped
&& (spte
& PT_PAGE_SIZE_MASK
)
1094 && (spte
& PT_PRESENT_MASK
))
1095 ++vcpu
->kvm
->stat
.lpages
;
1097 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1099 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1100 if (!is_rmap_pte(*shadow_pte
))
1101 kvm_release_pfn_clean(pfn
);
1104 kvm_release_pfn_dirty(pfn
);
1106 kvm_release_pfn_clean(pfn
);
1108 if (!ptwrite
|| !*ptwrite
)
1109 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1112 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1116 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1117 int largepage
, gfn_t gfn
, pfn_t pfn
,
1120 hpa_t table_addr
= vcpu
->arch
.mmu
.root_hpa
;
1124 u32 index
= PT64_INDEX(v
, level
);
1127 ASSERT(VALID_PAGE(table_addr
));
1128 table
= __va(table_addr
);
1131 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1132 0, write
, 1, &pt_write
, 0, gfn
, pfn
, false);
1136 if (largepage
&& level
== 2) {
1137 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1138 0, write
, 1, &pt_write
, 1, gfn
, pfn
, false);
1142 if (table
[index
] == shadow_trap_nonpresent_pte
) {
1143 struct kvm_mmu_page
*new_table
;
1146 pseudo_gfn
= (v
& PT64_DIR_BASE_ADDR_MASK
)
1148 new_table
= kvm_mmu_get_page(vcpu
, pseudo_gfn
,
1150 1, ACC_ALL
, &table
[index
]);
1152 pgprintk("nonpaging_map: ENOMEM\n");
1153 kvm_release_pfn_clean(pfn
);
1157 table
[index
] = __pa(new_table
->spt
) | PT_PRESENT_MASK
1158 | PT_WRITABLE_MASK
| PT_USER_MASK
;
1160 table_addr
= table
[index
] & PT64_BASE_ADDR_MASK
;
1164 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1170 down_read(¤t
->mm
->mmap_sem
);
1171 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1172 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1176 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1177 up_read(¤t
->mm
->mmap_sem
);
1180 if (is_error_pfn(pfn
)) {
1181 kvm_release_pfn_clean(pfn
);
1185 spin_lock(&vcpu
->kvm
->mmu_lock
);
1186 kvm_mmu_free_some_pages(vcpu
);
1187 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
,
1189 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1196 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
1197 struct kvm_mmu_page
*sp
)
1201 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1202 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
1205 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1208 struct kvm_mmu_page
*sp
;
1210 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1212 spin_lock(&vcpu
->kvm
->mmu_lock
);
1213 #ifdef CONFIG_X86_64
1214 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1215 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1217 sp
= page_header(root
);
1219 if (!sp
->root_count
&& sp
->role
.invalid
)
1220 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1221 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1222 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1226 for (i
= 0; i
< 4; ++i
) {
1227 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1230 root
&= PT64_BASE_ADDR_MASK
;
1231 sp
= page_header(root
);
1233 if (!sp
->root_count
&& sp
->role
.invalid
)
1234 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1236 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1238 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1239 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1242 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1246 struct kvm_mmu_page
*sp
;
1247 int metaphysical
= 0;
1249 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1251 #ifdef CONFIG_X86_64
1252 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1253 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1255 ASSERT(!VALID_PAGE(root
));
1258 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1259 PT64_ROOT_LEVEL
, metaphysical
,
1261 root
= __pa(sp
->spt
);
1263 vcpu
->arch
.mmu
.root_hpa
= root
;
1267 metaphysical
= !is_paging(vcpu
);
1270 for (i
= 0; i
< 4; ++i
) {
1271 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1273 ASSERT(!VALID_PAGE(root
));
1274 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1275 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1276 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1279 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1280 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1282 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1283 PT32_ROOT_LEVEL
, metaphysical
,
1285 root
= __pa(sp
->spt
);
1287 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1289 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1292 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
1297 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
1303 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
1304 r
= mmu_topup_memory_caches(vcpu
);
1309 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1311 gfn
= gva
>> PAGE_SHIFT
;
1313 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
1314 error_code
& PFERR_WRITE_MASK
, gfn
);
1317 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
1323 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1326 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1328 r
= mmu_topup_memory_caches(vcpu
);
1332 down_read(¤t
->mm
->mmap_sem
);
1333 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1334 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1337 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1338 up_read(¤t
->mm
->mmap_sem
);
1339 if (is_error_pfn(pfn
)) {
1340 kvm_release_pfn_clean(pfn
);
1343 spin_lock(&vcpu
->kvm
->mmu_lock
);
1344 kvm_mmu_free_some_pages(vcpu
);
1345 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
1346 largepage
, gfn
, pfn
, kvm_x86_ops
->get_tdp_level());
1347 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1352 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
1354 mmu_free_roots(vcpu
);
1357 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
1359 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1361 context
->new_cr3
= nonpaging_new_cr3
;
1362 context
->page_fault
= nonpaging_page_fault
;
1363 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1364 context
->free
= nonpaging_free
;
1365 context
->prefetch_page
= nonpaging_prefetch_page
;
1366 context
->root_level
= 0;
1367 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1368 context
->root_hpa
= INVALID_PAGE
;
1372 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
1374 ++vcpu
->stat
.tlb_flush
;
1375 kvm_x86_ops
->tlb_flush(vcpu
);
1378 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
1380 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
1381 mmu_free_roots(vcpu
);
1384 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
1388 kvm_inject_page_fault(vcpu
, addr
, err_code
);
1391 static void paging_free(struct kvm_vcpu
*vcpu
)
1393 nonpaging_free(vcpu
);
1397 #include "paging_tmpl.h"
1401 #include "paging_tmpl.h"
1404 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
1406 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1408 ASSERT(is_pae(vcpu
));
1409 context
->new_cr3
= paging_new_cr3
;
1410 context
->page_fault
= paging64_page_fault
;
1411 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1412 context
->prefetch_page
= paging64_prefetch_page
;
1413 context
->free
= paging_free
;
1414 context
->root_level
= level
;
1415 context
->shadow_root_level
= level
;
1416 context
->root_hpa
= INVALID_PAGE
;
1420 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
1422 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
1425 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
1427 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1429 context
->new_cr3
= paging_new_cr3
;
1430 context
->page_fault
= paging32_page_fault
;
1431 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1432 context
->free
= paging_free
;
1433 context
->prefetch_page
= paging32_prefetch_page
;
1434 context
->root_level
= PT32_ROOT_LEVEL
;
1435 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1436 context
->root_hpa
= INVALID_PAGE
;
1440 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
1442 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
1445 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
1447 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1449 context
->new_cr3
= nonpaging_new_cr3
;
1450 context
->page_fault
= tdp_page_fault
;
1451 context
->free
= nonpaging_free
;
1452 context
->prefetch_page
= nonpaging_prefetch_page
;
1453 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
1454 context
->root_hpa
= INVALID_PAGE
;
1456 if (!is_paging(vcpu
)) {
1457 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1458 context
->root_level
= 0;
1459 } else if (is_long_mode(vcpu
)) {
1460 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1461 context
->root_level
= PT64_ROOT_LEVEL
;
1462 } else if (is_pae(vcpu
)) {
1463 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1464 context
->root_level
= PT32E_ROOT_LEVEL
;
1466 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1467 context
->root_level
= PT32_ROOT_LEVEL
;
1473 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
1476 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1478 if (!is_paging(vcpu
))
1479 return nonpaging_init_context(vcpu
);
1480 else if (is_long_mode(vcpu
))
1481 return paging64_init_context(vcpu
);
1482 else if (is_pae(vcpu
))
1483 return paging32E_init_context(vcpu
);
1485 return paging32_init_context(vcpu
);
1488 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
1490 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
1493 return init_kvm_tdp_mmu(vcpu
);
1495 return init_kvm_softmmu(vcpu
);
1498 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
1501 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
1502 vcpu
->arch
.mmu
.free(vcpu
);
1503 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1507 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
1509 destroy_kvm_mmu(vcpu
);
1510 return init_kvm_mmu(vcpu
);
1512 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
1514 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
1518 r
= mmu_topup_memory_caches(vcpu
);
1521 spin_lock(&vcpu
->kvm
->mmu_lock
);
1522 kvm_mmu_free_some_pages(vcpu
);
1523 mmu_alloc_roots(vcpu
);
1524 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1525 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
1526 kvm_mmu_flush_tlb(vcpu
);
1530 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
1532 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
1534 mmu_free_roots(vcpu
);
1537 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
1538 struct kvm_mmu_page
*sp
,
1542 struct kvm_mmu_page
*child
;
1545 if (is_shadow_present_pte(pte
)) {
1546 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
1548 rmap_remove(vcpu
->kvm
, spte
);
1550 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1551 mmu_page_remove_parent_pte(child
, spte
);
1554 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
1555 if (is_large_pte(pte
))
1556 --vcpu
->kvm
->stat
.lpages
;
1559 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
1560 struct kvm_mmu_page
*sp
,
1564 if ((sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1565 && !vcpu
->arch
.update_pte
.largepage
) {
1566 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
1570 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
1571 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
1572 paging32_update_pte(vcpu
, sp
, spte
, new);
1574 paging64_update_pte(vcpu
, sp
, spte
, new);
1577 static bool need_remote_flush(u64 old
, u64
new)
1579 if (!is_shadow_present_pte(old
))
1581 if (!is_shadow_present_pte(new))
1583 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
1585 old
^= PT64_NX_MASK
;
1586 new ^= PT64_NX_MASK
;
1587 return (old
& ~new & PT64_PERM_MASK
) != 0;
1590 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
1592 if (need_remote_flush(old
, new))
1593 kvm_flush_remote_tlbs(vcpu
->kvm
);
1595 kvm_mmu_flush_tlb(vcpu
);
1598 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
1600 u64
*spte
= vcpu
->arch
.last_pte_updated
;
1602 return !!(spte
&& (*spte
& PT_ACCESSED_MASK
));
1605 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1606 const u8
*new, int bytes
)
1613 vcpu
->arch
.update_pte
.largepage
= 0;
1615 if (bytes
!= 4 && bytes
!= 8)
1619 * Assume that the pte write on a page table of the same type
1620 * as the current vcpu paging mode. This is nearly always true
1621 * (might be false while changing modes). Note it is verified later
1625 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
1626 if ((bytes
== 4) && (gpa
% 4 == 0)) {
1627 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
1630 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
1631 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
1632 memcpy((void *)&gpte
, new, 8);
1635 if ((bytes
== 4) && (gpa
% 4 == 0))
1636 memcpy((void *)&gpte
, new, 4);
1638 if (!is_present_pte(gpte
))
1640 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1642 down_read(¤t
->mm
->mmap_sem
);
1643 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
1644 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1645 vcpu
->arch
.update_pte
.largepage
= 1;
1647 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1648 up_read(¤t
->mm
->mmap_sem
);
1650 if (is_error_pfn(pfn
)) {
1651 kvm_release_pfn_clean(pfn
);
1654 vcpu
->arch
.update_pte
.gfn
= gfn
;
1655 vcpu
->arch
.update_pte
.pfn
= pfn
;
1658 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1659 const u8
*new, int bytes
)
1661 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1662 struct kvm_mmu_page
*sp
;
1663 struct hlist_node
*node
, *n
;
1664 struct hlist_head
*bucket
;
1668 unsigned offset
= offset_in_page(gpa
);
1670 unsigned page_offset
;
1671 unsigned misaligned
;
1678 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
1679 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
1680 spin_lock(&vcpu
->kvm
->mmu_lock
);
1681 kvm_mmu_free_some_pages(vcpu
);
1682 ++vcpu
->kvm
->stat
.mmu_pte_write
;
1683 kvm_mmu_audit(vcpu
, "pre pte write");
1684 if (gfn
== vcpu
->arch
.last_pt_write_gfn
1685 && !last_updated_pte_accessed(vcpu
)) {
1686 ++vcpu
->arch
.last_pt_write_count
;
1687 if (vcpu
->arch
.last_pt_write_count
>= 3)
1690 vcpu
->arch
.last_pt_write_gfn
= gfn
;
1691 vcpu
->arch
.last_pt_write_count
= 1;
1692 vcpu
->arch
.last_pte_updated
= NULL
;
1694 index
= kvm_page_table_hashfn(gfn
);
1695 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1696 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
1697 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
)
1699 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
1700 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
1701 misaligned
|= bytes
< 4;
1702 if (misaligned
|| flooded
) {
1704 * Misaligned accesses are too much trouble to fix
1705 * up; also, they usually indicate a page is not used
1708 * If we're seeing too many writes to a page,
1709 * it may no longer be a page table, or we may be
1710 * forking, in which case it is better to unmap the
1713 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
1714 gpa
, bytes
, sp
->role
.word
);
1715 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1716 ++vcpu
->kvm
->stat
.mmu_flooded
;
1719 page_offset
= offset
;
1720 level
= sp
->role
.level
;
1722 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
1723 page_offset
<<= 1; /* 32->64 */
1725 * A 32-bit pde maps 4MB while the shadow pdes map
1726 * only 2MB. So we need to double the offset again
1727 * and zap two pdes instead of one.
1729 if (level
== PT32_ROOT_LEVEL
) {
1730 page_offset
&= ~7; /* kill rounding error */
1734 quadrant
= page_offset
>> PAGE_SHIFT
;
1735 page_offset
&= ~PAGE_MASK
;
1736 if (quadrant
!= sp
->role
.quadrant
)
1739 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
1740 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
1742 r
= kvm_read_guest_atomic(vcpu
->kvm
,
1743 gpa
& ~(u64
)(pte_size
- 1),
1745 new = (const void *)&gentry
;
1751 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
1753 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
1754 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
1758 kvm_mmu_audit(vcpu
, "post pte write");
1759 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1760 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
1761 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
1762 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
1766 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
1771 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1773 spin_lock(&vcpu
->kvm
->mmu_lock
);
1774 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1775 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1779 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
1781 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
1782 struct kvm_mmu_page
*sp
;
1784 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
1785 struct kvm_mmu_page
, link
);
1786 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1787 ++vcpu
->kvm
->stat
.mmu_recycled
;
1791 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
1794 enum emulation_result er
;
1796 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
1805 r
= mmu_topup_memory_caches(vcpu
);
1809 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
1814 case EMULATE_DO_MMIO
:
1815 ++vcpu
->stat
.mmio_exits
;
1818 kvm_report_emulation_failure(vcpu
, "pagetable");
1826 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
1828 void kvm_enable_tdp(void)
1832 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
1834 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
1836 struct kvm_mmu_page
*sp
;
1838 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
1839 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
1840 struct kvm_mmu_page
, link
);
1841 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1843 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
1846 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
1853 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
1854 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1855 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
1857 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1858 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
1860 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
1861 * Therefore we need to allocate shadow page tables in the first
1862 * 4GB of memory, which happens to fit the DMA32 zone.
1864 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
1867 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
1868 for (i
= 0; i
< 4; ++i
)
1869 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1874 free_mmu_pages(vcpu
);
1878 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
1881 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1883 return alloc_mmu_pages(vcpu
);
1886 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
1889 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1891 return init_kvm_mmu(vcpu
);
1894 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
1898 destroy_kvm_mmu(vcpu
);
1899 free_mmu_pages(vcpu
);
1900 mmu_free_memory_caches(vcpu
);
1903 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
1905 struct kvm_mmu_page
*sp
;
1907 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
1911 if (!test_bit(slot
, &sp
->slot_bitmap
))
1915 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1917 if (pt
[i
] & PT_WRITABLE_MASK
)
1918 pt
[i
] &= ~PT_WRITABLE_MASK
;
1922 void kvm_mmu_zap_all(struct kvm
*kvm
)
1924 struct kvm_mmu_page
*sp
, *node
;
1926 spin_lock(&kvm
->mmu_lock
);
1927 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
1928 kvm_mmu_zap_page(kvm
, sp
);
1929 spin_unlock(&kvm
->mmu_lock
);
1931 kvm_flush_remote_tlbs(kvm
);
1934 void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
1936 struct kvm_mmu_page
*page
;
1938 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1939 struct kvm_mmu_page
, link
);
1940 kvm_mmu_zap_page(kvm
, page
);
1943 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
1946 struct kvm
*kvm_freed
= NULL
;
1947 int cache_count
= 0;
1949 spin_lock(&kvm_lock
);
1951 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
1954 spin_lock(&kvm
->mmu_lock
);
1955 npages
= kvm
->arch
.n_alloc_mmu_pages
-
1956 kvm
->arch
.n_free_mmu_pages
;
1957 cache_count
+= npages
;
1958 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
1959 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
1965 spin_unlock(&kvm
->mmu_lock
);
1968 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
1970 spin_unlock(&kvm_lock
);
1975 static struct shrinker mmu_shrinker
= {
1976 .shrink
= mmu_shrink
,
1977 .seeks
= DEFAULT_SEEKS
* 10,
1980 void mmu_destroy_caches(void)
1982 if (pte_chain_cache
)
1983 kmem_cache_destroy(pte_chain_cache
);
1984 if (rmap_desc_cache
)
1985 kmem_cache_destroy(rmap_desc_cache
);
1986 if (mmu_page_header_cache
)
1987 kmem_cache_destroy(mmu_page_header_cache
);
1990 void kvm_mmu_module_exit(void)
1992 mmu_destroy_caches();
1993 unregister_shrinker(&mmu_shrinker
);
1996 int kvm_mmu_module_init(void)
1998 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
1999 sizeof(struct kvm_pte_chain
),
2001 if (!pte_chain_cache
)
2003 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2004 sizeof(struct kvm_rmap_desc
),
2006 if (!rmap_desc_cache
)
2009 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2010 sizeof(struct kvm_mmu_page
),
2012 if (!mmu_page_header_cache
)
2015 register_shrinker(&mmu_shrinker
);
2020 mmu_destroy_caches();
2025 * Caculate mmu pages needed for kvm.
2027 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2030 unsigned int nr_mmu_pages
;
2031 unsigned int nr_pages
= 0;
2033 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2034 nr_pages
+= kvm
->memslots
[i
].npages
;
2036 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2037 nr_mmu_pages
= max(nr_mmu_pages
,
2038 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2040 return nr_mmu_pages
;
2043 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2046 if (len
> buffer
->len
)
2051 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2056 ret
= pv_mmu_peek_buffer(buffer
, len
);
2061 buffer
->processed
+= len
;
2065 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2066 gpa_t addr
, gpa_t value
)
2071 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2074 r
= mmu_topup_memory_caches(vcpu
);
2078 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2084 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2086 kvm_x86_ops
->tlb_flush(vcpu
);
2090 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2092 spin_lock(&vcpu
->kvm
->mmu_lock
);
2093 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2094 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2098 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2099 struct kvm_pv_mmu_op_buffer
*buffer
)
2101 struct kvm_mmu_op_header
*header
;
2103 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2106 switch (header
->op
) {
2107 case KVM_MMU_OP_WRITE_PTE
: {
2108 struct kvm_mmu_op_write_pte
*wpte
;
2110 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2113 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2116 case KVM_MMU_OP_FLUSH_TLB
: {
2117 struct kvm_mmu_op_flush_tlb
*ftlb
;
2119 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2122 return kvm_pv_mmu_flush_tlb(vcpu
);
2124 case KVM_MMU_OP_RELEASE_PT
: {
2125 struct kvm_mmu_op_release_pt
*rpt
;
2127 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2130 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2136 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2137 gpa_t addr
, unsigned long *ret
)
2140 struct kvm_pv_mmu_op_buffer buffer
;
2142 buffer
.ptr
= buffer
.buf
;
2143 buffer
.len
= min_t(unsigned long, bytes
, sizeof buffer
.buf
);
2144 buffer
.processed
= 0;
2146 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
.buf
, buffer
.len
);
2150 while (buffer
.len
) {
2151 r
= kvm_pv_mmu_op_one(vcpu
, &buffer
);
2160 *ret
= buffer
.processed
;
2166 static const char *audit_msg
;
2168 static gva_t
canonicalize(gva_t gva
)
2170 #ifdef CONFIG_X86_64
2171 gva
= (long long)(gva
<< 16) >> 16;
2176 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2177 gva_t va
, int level
)
2179 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
2181 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
2183 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
2186 if (ent
== shadow_trap_nonpresent_pte
)
2189 va
= canonicalize(va
);
2191 if (ent
== shadow_notrap_nonpresent_pte
)
2192 printk(KERN_ERR
"audit: (%s) nontrapping pte"
2193 " in nonleaf level: levels %d gva %lx"
2194 " level %d pte %llx\n", audit_msg
,
2195 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
2197 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
2199 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
2200 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
2202 if (is_shadow_present_pte(ent
)
2203 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
2204 printk(KERN_ERR
"xx audit error: (%s) levels %d"
2205 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
2206 audit_msg
, vcpu
->arch
.mmu
.root_level
,
2208 is_shadow_present_pte(ent
));
2209 else if (ent
== shadow_notrap_nonpresent_pte
2210 && !is_error_hpa(hpa
))
2211 printk(KERN_ERR
"audit: (%s) notrap shadow,"
2212 " valid guest gva %lx\n", audit_msg
, va
);
2213 kvm_release_pfn_clean(pfn
);
2219 static void audit_mappings(struct kvm_vcpu
*vcpu
)
2223 if (vcpu
->arch
.mmu
.root_level
== 4)
2224 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
2226 for (i
= 0; i
< 4; ++i
)
2227 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
2228 audit_mappings_page(vcpu
,
2229 vcpu
->arch
.mmu
.pae_root
[i
],
2234 static int count_rmaps(struct kvm_vcpu
*vcpu
)
2239 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
2240 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
2241 struct kvm_rmap_desc
*d
;
2243 for (j
= 0; j
< m
->npages
; ++j
) {
2244 unsigned long *rmapp
= &m
->rmap
[j
];
2248 if (!(*rmapp
& 1)) {
2252 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
2254 for (k
= 0; k
< RMAP_EXT
; ++k
)
2255 if (d
->shadow_ptes
[k
])
2266 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
2269 struct kvm_mmu_page
*sp
;
2272 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2275 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
2278 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
2281 if (!(ent
& PT_PRESENT_MASK
))
2283 if (!(ent
& PT_WRITABLE_MASK
))
2291 static void audit_rmap(struct kvm_vcpu
*vcpu
)
2293 int n_rmap
= count_rmaps(vcpu
);
2294 int n_actual
= count_writable_mappings(vcpu
);
2296 if (n_rmap
!= n_actual
)
2297 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
2298 __func__
, audit_msg
, n_rmap
, n_actual
);
2301 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
2303 struct kvm_mmu_page
*sp
;
2304 struct kvm_memory_slot
*slot
;
2305 unsigned long *rmapp
;
2308 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2309 if (sp
->role
.metaphysical
)
2312 slot
= gfn_to_memslot(vcpu
->kvm
, sp
->gfn
);
2313 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
2314 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
2316 printk(KERN_ERR
"%s: (%s) shadow page has writable"
2317 " mappings: gfn %lx role %x\n",
2318 __func__
, audit_msg
, sp
->gfn
,
2323 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
2330 audit_write_protection(vcpu
);
2331 audit_mappings(vcpu
);