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
;
155 static u64 __read_mostly shadow_base_present_pte
;
156 static u64 __read_mostly shadow_nx_mask
;
157 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
158 static u64 __read_mostly shadow_user_mask
;
159 static u64 __read_mostly shadow_accessed_mask
;
160 static u64 __read_mostly shadow_dirty_mask
;
162 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
164 shadow_trap_nonpresent_pte
= trap_pte
;
165 shadow_notrap_nonpresent_pte
= notrap_pte
;
167 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
169 void kvm_mmu_set_base_ptes(u64 base_pte
)
171 shadow_base_present_pte
= base_pte
;
173 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes
);
175 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
176 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
)
178 shadow_user_mask
= user_mask
;
179 shadow_accessed_mask
= accessed_mask
;
180 shadow_dirty_mask
= dirty_mask
;
181 shadow_nx_mask
= nx_mask
;
182 shadow_x_mask
= x_mask
;
184 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
186 static int is_write_protection(struct kvm_vcpu
*vcpu
)
188 return vcpu
->arch
.cr0
& X86_CR0_WP
;
191 static int is_cpuid_PSE36(void)
196 static int is_nx(struct kvm_vcpu
*vcpu
)
198 return vcpu
->arch
.shadow_efer
& EFER_NX
;
201 static int is_present_pte(unsigned long pte
)
203 return pte
& PT_PRESENT_MASK
;
206 static int is_shadow_present_pte(u64 pte
)
208 return pte
!= shadow_trap_nonpresent_pte
209 && pte
!= shadow_notrap_nonpresent_pte
;
212 static int is_large_pte(u64 pte
)
214 return pte
& PT_PAGE_SIZE_MASK
;
217 static int is_writeble_pte(unsigned long pte
)
219 return pte
& PT_WRITABLE_MASK
;
222 static int is_dirty_pte(unsigned long pte
)
224 return pte
& shadow_dirty_mask
;
227 static int is_rmap_pte(u64 pte
)
229 return is_shadow_present_pte(pte
);
232 static pfn_t
spte_to_pfn(u64 pte
)
234 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
237 static gfn_t
pse36_gfn_delta(u32 gpte
)
239 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
241 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
244 static void set_shadow_pte(u64
*sptep
, u64 spte
)
247 set_64bit((unsigned long *)sptep
, spte
);
249 set_64bit((unsigned long long *)sptep
, spte
);
253 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
254 struct kmem_cache
*base_cache
, int min
)
258 if (cache
->nobjs
>= min
)
260 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
261 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
264 cache
->objects
[cache
->nobjs
++] = obj
;
269 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
272 kfree(mc
->objects
[--mc
->nobjs
]);
275 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
280 if (cache
->nobjs
>= min
)
282 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
283 page
= alloc_page(GFP_KERNEL
);
286 set_page_private(page
, 0);
287 cache
->objects
[cache
->nobjs
++] = page_address(page
);
292 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
295 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
298 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
302 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
306 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
310 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
313 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
314 mmu_page_header_cache
, 4);
319 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
321 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
322 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
323 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
324 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
327 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
333 p
= mc
->objects
[--mc
->nobjs
];
338 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
340 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
341 sizeof(struct kvm_pte_chain
));
344 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
349 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
351 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
352 sizeof(struct kvm_rmap_desc
));
355 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
361 * Return the pointer to the largepage write count for a given
362 * gfn, handling slots that are not large page aligned.
364 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
368 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
369 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
370 return &slot
->lpage_info
[idx
].write_count
;
373 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
377 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
381 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
385 write_count
= slot_largepage_idx(gfn
, gfn_to_memslot(kvm
, gfn
));
387 WARN_ON(*write_count
< 0);
390 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
392 struct kvm_memory_slot
*slot
= gfn_to_memslot(kvm
, gfn
);
396 largepage_idx
= slot_largepage_idx(gfn
, slot
);
397 return *largepage_idx
;
403 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
405 struct vm_area_struct
*vma
;
408 addr
= gfn_to_hva(kvm
, gfn
);
409 if (kvm_is_error_hva(addr
))
412 vma
= find_vma(current
->mm
, addr
);
413 if (vma
&& is_vm_hugetlb_page(vma
))
419 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
421 struct kvm_memory_slot
*slot
;
423 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
426 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
429 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
430 if (slot
&& slot
->dirty_bitmap
)
437 * Take gfn and return the reverse mapping to it.
438 * Note: gfn must be unaliased before this function get called
441 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
443 struct kvm_memory_slot
*slot
;
446 slot
= gfn_to_memslot(kvm
, gfn
);
448 return &slot
->rmap
[gfn
- slot
->base_gfn
];
450 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
451 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
453 return &slot
->lpage_info
[idx
].rmap_pde
;
457 * Reverse mapping data structures:
459 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
460 * that points to page_address(page).
462 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
463 * containing more mappings.
465 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
467 struct kvm_mmu_page
*sp
;
468 struct kvm_rmap_desc
*desc
;
469 unsigned long *rmapp
;
472 if (!is_rmap_pte(*spte
))
474 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
475 sp
= page_header(__pa(spte
));
476 sp
->gfns
[spte
- sp
->spt
] = gfn
;
477 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
479 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
480 *rmapp
= (unsigned long)spte
;
481 } else if (!(*rmapp
& 1)) {
482 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
483 desc
= mmu_alloc_rmap_desc(vcpu
);
484 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
485 desc
->shadow_ptes
[1] = spte
;
486 *rmapp
= (unsigned long)desc
| 1;
488 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
489 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
490 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
492 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
493 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
496 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
498 desc
->shadow_ptes
[i
] = spte
;
502 static void rmap_desc_remove_entry(unsigned long *rmapp
,
503 struct kvm_rmap_desc
*desc
,
505 struct kvm_rmap_desc
*prev_desc
)
509 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
511 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
512 desc
->shadow_ptes
[j
] = NULL
;
515 if (!prev_desc
&& !desc
->more
)
516 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
519 prev_desc
->more
= desc
->more
;
521 *rmapp
= (unsigned long)desc
->more
| 1;
522 mmu_free_rmap_desc(desc
);
525 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
527 struct kvm_rmap_desc
*desc
;
528 struct kvm_rmap_desc
*prev_desc
;
529 struct kvm_mmu_page
*sp
;
531 unsigned long *rmapp
;
534 if (!is_rmap_pte(*spte
))
536 sp
= page_header(__pa(spte
));
537 pfn
= spte_to_pfn(*spte
);
538 if (*spte
& shadow_accessed_mask
)
539 kvm_set_pfn_accessed(pfn
);
540 if (is_writeble_pte(*spte
))
541 kvm_release_pfn_dirty(pfn
);
543 kvm_release_pfn_clean(pfn
);
544 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
546 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
548 } else if (!(*rmapp
& 1)) {
549 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
550 if ((u64
*)*rmapp
!= spte
) {
551 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
557 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
558 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
561 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
562 if (desc
->shadow_ptes
[i
] == spte
) {
563 rmap_desc_remove_entry(rmapp
,
575 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
577 struct kvm_rmap_desc
*desc
;
578 struct kvm_rmap_desc
*prev_desc
;
584 else if (!(*rmapp
& 1)) {
586 return (u64
*)*rmapp
;
589 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
593 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
594 if (prev_spte
== spte
)
595 return desc
->shadow_ptes
[i
];
596 prev_spte
= desc
->shadow_ptes
[i
];
603 static void rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
605 unsigned long *rmapp
;
607 int write_protected
= 0;
609 gfn
= unalias_gfn(kvm
, gfn
);
610 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
612 spte
= rmap_next(kvm
, rmapp
, NULL
);
615 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
616 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
617 if (is_writeble_pte(*spte
)) {
618 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
621 spte
= rmap_next(kvm
, rmapp
, spte
);
623 if (write_protected
) {
626 spte
= rmap_next(kvm
, rmapp
, NULL
);
627 pfn
= spte_to_pfn(*spte
);
628 kvm_set_pfn_dirty(pfn
);
631 /* check for huge page mappings */
632 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
633 spte
= rmap_next(kvm
, rmapp
, NULL
);
636 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
637 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
638 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
639 if (is_writeble_pte(*spte
)) {
640 rmap_remove(kvm
, spte
);
642 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
646 spte
= rmap_next(kvm
, rmapp
, spte
);
650 kvm_flush_remote_tlbs(kvm
);
652 account_shadowed(kvm
, gfn
);
656 static int is_empty_shadow_page(u64
*spt
)
661 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
662 if (is_shadow_present_pte(*pos
)) {
663 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
671 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
673 ASSERT(is_empty_shadow_page(sp
->spt
));
675 __free_page(virt_to_page(sp
->spt
));
676 __free_page(virt_to_page(sp
->gfns
));
678 ++kvm
->arch
.n_free_mmu_pages
;
681 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
683 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
686 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
689 struct kvm_mmu_page
*sp
;
691 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
692 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
693 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
694 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
695 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
696 ASSERT(is_empty_shadow_page(sp
->spt
));
699 sp
->parent_pte
= parent_pte
;
700 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
704 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
705 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
707 struct kvm_pte_chain
*pte_chain
;
708 struct hlist_node
*node
;
713 if (!sp
->multimapped
) {
714 u64
*old
= sp
->parent_pte
;
717 sp
->parent_pte
= parent_pte
;
721 pte_chain
= mmu_alloc_pte_chain(vcpu
);
722 INIT_HLIST_HEAD(&sp
->parent_ptes
);
723 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
724 pte_chain
->parent_ptes
[0] = old
;
726 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
727 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
729 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
730 if (!pte_chain
->parent_ptes
[i
]) {
731 pte_chain
->parent_ptes
[i
] = parent_pte
;
735 pte_chain
= mmu_alloc_pte_chain(vcpu
);
737 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
738 pte_chain
->parent_ptes
[0] = parent_pte
;
741 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
744 struct kvm_pte_chain
*pte_chain
;
745 struct hlist_node
*node
;
748 if (!sp
->multimapped
) {
749 BUG_ON(sp
->parent_pte
!= parent_pte
);
750 sp
->parent_pte
= NULL
;
753 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
754 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
755 if (!pte_chain
->parent_ptes
[i
])
757 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
759 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
760 && pte_chain
->parent_ptes
[i
+ 1]) {
761 pte_chain
->parent_ptes
[i
]
762 = pte_chain
->parent_ptes
[i
+ 1];
765 pte_chain
->parent_ptes
[i
] = NULL
;
767 hlist_del(&pte_chain
->link
);
768 mmu_free_pte_chain(pte_chain
);
769 if (hlist_empty(&sp
->parent_ptes
)) {
771 sp
->parent_pte
= NULL
;
779 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
782 struct hlist_head
*bucket
;
783 struct kvm_mmu_page
*sp
;
784 struct hlist_node
*node
;
786 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
787 index
= kvm_page_table_hashfn(gfn
);
788 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
789 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
790 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
791 && !sp
->role
.invalid
) {
792 pgprintk("%s: found role %x\n",
793 __func__
, sp
->role
.word
);
799 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
807 union kvm_mmu_page_role role
;
810 struct hlist_head
*bucket
;
811 struct kvm_mmu_page
*sp
;
812 struct hlist_node
*node
;
815 role
.glevels
= vcpu
->arch
.mmu
.root_level
;
817 role
.metaphysical
= metaphysical
;
818 role
.access
= access
;
819 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
820 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
821 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
822 role
.quadrant
= quadrant
;
824 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
826 index
= kvm_page_table_hashfn(gfn
);
827 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
828 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
829 if (sp
->gfn
== gfn
&& sp
->role
.word
== role
.word
) {
830 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
831 pgprintk("%s: found\n", __func__
);
834 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
835 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
838 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
841 hlist_add_head(&sp
->hash_link
, bucket
);
843 rmap_write_protect(vcpu
->kvm
, gfn
);
844 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
848 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
849 struct kvm_mmu_page
*sp
)
857 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
858 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
859 if (is_shadow_present_pte(pt
[i
]))
860 rmap_remove(kvm
, &pt
[i
]);
861 pt
[i
] = shadow_trap_nonpresent_pte
;
863 kvm_flush_remote_tlbs(kvm
);
867 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
870 if (is_shadow_present_pte(ent
)) {
871 if (!is_large_pte(ent
)) {
872 ent
&= PT64_BASE_ADDR_MASK
;
873 mmu_page_remove_parent_pte(page_header(ent
),
877 rmap_remove(kvm
, &pt
[i
]);
880 pt
[i
] = shadow_trap_nonpresent_pte
;
882 kvm_flush_remote_tlbs(kvm
);
885 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
887 mmu_page_remove_parent_pte(sp
, parent_pte
);
890 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
894 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
896 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
899 static void kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
903 ++kvm
->stat
.mmu_shadow_zapped
;
904 while (sp
->multimapped
|| sp
->parent_pte
) {
905 if (!sp
->multimapped
)
906 parent_pte
= sp
->parent_pte
;
908 struct kvm_pte_chain
*chain
;
910 chain
= container_of(sp
->parent_ptes
.first
,
911 struct kvm_pte_chain
, link
);
912 parent_pte
= chain
->parent_ptes
[0];
915 kvm_mmu_put_page(sp
, parent_pte
);
916 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
918 kvm_mmu_page_unlink_children(kvm
, sp
);
919 if (!sp
->root_count
) {
920 if (!sp
->role
.metaphysical
)
921 unaccount_shadowed(kvm
, sp
->gfn
);
922 hlist_del(&sp
->hash_link
);
923 kvm_mmu_free_page(kvm
, sp
);
925 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
926 sp
->role
.invalid
= 1;
927 kvm_reload_remote_mmus(kvm
);
929 kvm_mmu_reset_last_pte_updated(kvm
);
933 * Changing the number of mmu pages allocated to the vm
934 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
936 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
939 * If we set the number of mmu pages to be smaller be than the
940 * number of actived pages , we must to free some mmu pages before we
944 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
946 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
947 - kvm
->arch
.n_free_mmu_pages
;
949 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
950 struct kvm_mmu_page
*page
;
952 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
953 struct kvm_mmu_page
, link
);
954 kvm_mmu_zap_page(kvm
, page
);
957 kvm
->arch
.n_free_mmu_pages
= 0;
960 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
961 - kvm
->arch
.n_alloc_mmu_pages
;
963 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
966 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
969 struct hlist_head
*bucket
;
970 struct kvm_mmu_page
*sp
;
971 struct hlist_node
*node
, *n
;
974 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
976 index
= kvm_page_table_hashfn(gfn
);
977 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
978 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
979 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
980 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
982 kvm_mmu_zap_page(kvm
, sp
);
988 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
990 struct kvm_mmu_page
*sp
;
992 while ((sp
= kvm_mmu_lookup_page(kvm
, gfn
)) != NULL
) {
993 pgprintk("%s: zap %lx %x\n", __func__
, gfn
, sp
->role
.word
);
994 kvm_mmu_zap_page(kvm
, sp
);
998 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1000 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1001 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1003 __set_bit(slot
, &sp
->slot_bitmap
);
1006 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1010 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1012 if (gpa
== UNMAPPED_GVA
)
1015 down_read(¤t
->mm
->mmap_sem
);
1016 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1017 up_read(¤t
->mm
->mmap_sem
);
1022 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1023 unsigned pt_access
, unsigned pte_access
,
1024 int user_fault
, int write_fault
, int dirty
,
1025 int *ptwrite
, int largepage
, gfn_t gfn
,
1026 pfn_t pfn
, bool speculative
)
1029 int was_rmapped
= 0;
1030 int was_writeble
= is_writeble_pte(*shadow_pte
);
1032 pgprintk("%s: spte %llx access %x write_fault %d"
1033 " user_fault %d gfn %lx\n",
1034 __func__
, *shadow_pte
, pt_access
,
1035 write_fault
, user_fault
, gfn
);
1037 if (is_rmap_pte(*shadow_pte
)) {
1039 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1040 * the parent of the now unreachable PTE.
1042 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1043 struct kvm_mmu_page
*child
;
1044 u64 pte
= *shadow_pte
;
1046 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1047 mmu_page_remove_parent_pte(child
, shadow_pte
);
1048 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1049 pgprintk("hfn old %lx new %lx\n",
1050 spte_to_pfn(*shadow_pte
), pfn
);
1051 rmap_remove(vcpu
->kvm
, shadow_pte
);
1054 was_rmapped
= is_large_pte(*shadow_pte
);
1061 * We don't set the accessed bit, since we sometimes want to see
1062 * whether the guest actually used the pte (in order to detect
1065 spte
= shadow_base_present_pte
| shadow_dirty_mask
;
1067 pte_access
|= PT_ACCESSED_MASK
;
1069 pte_access
&= ~ACC_WRITE_MASK
;
1070 if (pte_access
& ACC_EXEC_MASK
)
1071 spte
|= shadow_x_mask
;
1073 spte
|= shadow_nx_mask
;
1074 if (pte_access
& ACC_USER_MASK
)
1075 spte
|= shadow_user_mask
;
1077 spte
|= PT_PAGE_SIZE_MASK
;
1079 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1081 if ((pte_access
& ACC_WRITE_MASK
)
1082 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1083 struct kvm_mmu_page
*shadow
;
1085 spte
|= PT_WRITABLE_MASK
;
1087 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1089 (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
))) {
1090 pgprintk("%s: found shadow page for %lx, marking ro\n",
1092 pte_access
&= ~ACC_WRITE_MASK
;
1093 if (is_writeble_pte(spte
)) {
1094 spte
&= ~PT_WRITABLE_MASK
;
1095 kvm_x86_ops
->tlb_flush(vcpu
);
1102 if (pte_access
& ACC_WRITE_MASK
)
1103 mark_page_dirty(vcpu
->kvm
, gfn
);
1105 pgprintk("%s: setting spte %llx\n", __func__
, spte
);
1106 pgprintk("instantiating %s PTE (%s) at %d (%llx) addr %llx\n",
1107 (spte
&PT_PAGE_SIZE_MASK
)? "2MB" : "4kB",
1108 (spte
&PT_WRITABLE_MASK
)?"RW":"R", gfn
, spte
, shadow_pte
);
1109 set_shadow_pte(shadow_pte
, spte
);
1110 if (!was_rmapped
&& (spte
& PT_PAGE_SIZE_MASK
)
1111 && (spte
& PT_PRESENT_MASK
))
1112 ++vcpu
->kvm
->stat
.lpages
;
1114 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1116 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1117 if (!is_rmap_pte(*shadow_pte
))
1118 kvm_release_pfn_clean(pfn
);
1121 kvm_release_pfn_dirty(pfn
);
1123 kvm_release_pfn_clean(pfn
);
1125 if (!ptwrite
|| !*ptwrite
)
1126 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1129 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1133 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1134 int largepage
, gfn_t gfn
, pfn_t pfn
,
1137 hpa_t table_addr
= vcpu
->arch
.mmu
.root_hpa
;
1141 u32 index
= PT64_INDEX(v
, level
);
1144 ASSERT(VALID_PAGE(table_addr
));
1145 table
= __va(table_addr
);
1148 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1149 0, write
, 1, &pt_write
, 0, gfn
, pfn
, false);
1153 if (largepage
&& level
== 2) {
1154 mmu_set_spte(vcpu
, &table
[index
], ACC_ALL
, ACC_ALL
,
1155 0, write
, 1, &pt_write
, 1, gfn
, pfn
, false);
1159 if (table
[index
] == shadow_trap_nonpresent_pte
) {
1160 struct kvm_mmu_page
*new_table
;
1163 pseudo_gfn
= (v
& PT64_DIR_BASE_ADDR_MASK
)
1165 new_table
= kvm_mmu_get_page(vcpu
, pseudo_gfn
,
1167 1, ACC_ALL
, &table
[index
]);
1169 pgprintk("nonpaging_map: ENOMEM\n");
1170 kvm_release_pfn_clean(pfn
);
1174 table
[index
] = __pa(new_table
->spt
)
1175 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1176 | shadow_user_mask
| shadow_x_mask
;
1178 table_addr
= table
[index
] & PT64_BASE_ADDR_MASK
;
1182 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1188 down_read(¤t
->mm
->mmap_sem
);
1189 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1190 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1194 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1195 up_read(¤t
->mm
->mmap_sem
);
1198 if (is_error_pfn(pfn
)) {
1199 kvm_release_pfn_clean(pfn
);
1203 spin_lock(&vcpu
->kvm
->mmu_lock
);
1204 kvm_mmu_free_some_pages(vcpu
);
1205 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
,
1207 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1214 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
1215 struct kvm_mmu_page
*sp
)
1219 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1220 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
1223 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1226 struct kvm_mmu_page
*sp
;
1228 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1230 spin_lock(&vcpu
->kvm
->mmu_lock
);
1231 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1232 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1234 sp
= page_header(root
);
1236 if (!sp
->root_count
&& sp
->role
.invalid
)
1237 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1238 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1239 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1242 for (i
= 0; i
< 4; ++i
) {
1243 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1246 root
&= PT64_BASE_ADDR_MASK
;
1247 sp
= page_header(root
);
1249 if (!sp
->root_count
&& sp
->role
.invalid
)
1250 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1252 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1254 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1255 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1258 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1262 struct kvm_mmu_page
*sp
;
1263 int metaphysical
= 0;
1265 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1267 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1268 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1270 ASSERT(!VALID_PAGE(root
));
1273 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1274 PT64_ROOT_LEVEL
, metaphysical
,
1276 root
= __pa(sp
->spt
);
1278 vcpu
->arch
.mmu
.root_hpa
= root
;
1281 metaphysical
= !is_paging(vcpu
);
1284 for (i
= 0; i
< 4; ++i
) {
1285 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1287 ASSERT(!VALID_PAGE(root
));
1288 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1289 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1290 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1293 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1294 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1296 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1297 PT32_ROOT_LEVEL
, metaphysical
,
1299 root
= __pa(sp
->spt
);
1301 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1303 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1306 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
1311 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
1317 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
1318 r
= mmu_topup_memory_caches(vcpu
);
1323 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1325 gfn
= gva
>> PAGE_SHIFT
;
1327 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
1328 error_code
& PFERR_WRITE_MASK
, gfn
);
1331 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
1337 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1340 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1342 r
= mmu_topup_memory_caches(vcpu
);
1346 down_read(¤t
->mm
->mmap_sem
);
1347 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1348 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1351 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1352 up_read(¤t
->mm
->mmap_sem
);
1353 if (is_error_pfn(pfn
)) {
1354 kvm_release_pfn_clean(pfn
);
1357 spin_lock(&vcpu
->kvm
->mmu_lock
);
1358 kvm_mmu_free_some_pages(vcpu
);
1359 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
1360 largepage
, gfn
, pfn
, kvm_x86_ops
->get_tdp_level());
1361 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1366 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
1368 mmu_free_roots(vcpu
);
1371 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
1373 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1375 context
->new_cr3
= nonpaging_new_cr3
;
1376 context
->page_fault
= nonpaging_page_fault
;
1377 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1378 context
->free
= nonpaging_free
;
1379 context
->prefetch_page
= nonpaging_prefetch_page
;
1380 context
->root_level
= 0;
1381 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1382 context
->root_hpa
= INVALID_PAGE
;
1386 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
1388 ++vcpu
->stat
.tlb_flush
;
1389 kvm_x86_ops
->tlb_flush(vcpu
);
1392 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
1394 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
1395 mmu_free_roots(vcpu
);
1398 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
1402 kvm_inject_page_fault(vcpu
, addr
, err_code
);
1405 static void paging_free(struct kvm_vcpu
*vcpu
)
1407 nonpaging_free(vcpu
);
1411 #include "paging_tmpl.h"
1415 #include "paging_tmpl.h"
1418 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
1420 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1422 ASSERT(is_pae(vcpu
));
1423 context
->new_cr3
= paging_new_cr3
;
1424 context
->page_fault
= paging64_page_fault
;
1425 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1426 context
->prefetch_page
= paging64_prefetch_page
;
1427 context
->free
= paging_free
;
1428 context
->root_level
= level
;
1429 context
->shadow_root_level
= level
;
1430 context
->root_hpa
= INVALID_PAGE
;
1434 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
1436 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
1439 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
1441 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1443 context
->new_cr3
= paging_new_cr3
;
1444 context
->page_fault
= paging32_page_fault
;
1445 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1446 context
->free
= paging_free
;
1447 context
->prefetch_page
= paging32_prefetch_page
;
1448 context
->root_level
= PT32_ROOT_LEVEL
;
1449 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1450 context
->root_hpa
= INVALID_PAGE
;
1454 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
1456 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
1459 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
1461 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1463 context
->new_cr3
= nonpaging_new_cr3
;
1464 context
->page_fault
= tdp_page_fault
;
1465 context
->free
= nonpaging_free
;
1466 context
->prefetch_page
= nonpaging_prefetch_page
;
1467 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
1468 context
->root_hpa
= INVALID_PAGE
;
1470 if (!is_paging(vcpu
)) {
1471 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1472 context
->root_level
= 0;
1473 } else if (is_long_mode(vcpu
)) {
1474 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1475 context
->root_level
= PT64_ROOT_LEVEL
;
1476 } else if (is_pae(vcpu
)) {
1477 context
->gva_to_gpa
= paging64_gva_to_gpa
;
1478 context
->root_level
= PT32E_ROOT_LEVEL
;
1480 context
->gva_to_gpa
= paging32_gva_to_gpa
;
1481 context
->root_level
= PT32_ROOT_LEVEL
;
1487 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
1490 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1492 if (!is_paging(vcpu
))
1493 return nonpaging_init_context(vcpu
);
1494 else if (is_long_mode(vcpu
))
1495 return paging64_init_context(vcpu
);
1496 else if (is_pae(vcpu
))
1497 return paging32E_init_context(vcpu
);
1499 return paging32_init_context(vcpu
);
1502 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
1504 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
1507 return init_kvm_tdp_mmu(vcpu
);
1509 return init_kvm_softmmu(vcpu
);
1512 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
1515 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
1516 vcpu
->arch
.mmu
.free(vcpu
);
1517 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1521 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
1523 destroy_kvm_mmu(vcpu
);
1524 return init_kvm_mmu(vcpu
);
1526 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
1528 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
1532 r
= mmu_topup_memory_caches(vcpu
);
1535 spin_lock(&vcpu
->kvm
->mmu_lock
);
1536 kvm_mmu_free_some_pages(vcpu
);
1537 mmu_alloc_roots(vcpu
);
1538 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1539 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
1540 kvm_mmu_flush_tlb(vcpu
);
1544 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
1546 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
1548 mmu_free_roots(vcpu
);
1551 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
1552 struct kvm_mmu_page
*sp
,
1556 struct kvm_mmu_page
*child
;
1559 if (is_shadow_present_pte(pte
)) {
1560 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
1562 rmap_remove(vcpu
->kvm
, spte
);
1564 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1565 mmu_page_remove_parent_pte(child
, spte
);
1568 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
1569 if (is_large_pte(pte
))
1570 --vcpu
->kvm
->stat
.lpages
;
1573 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
1574 struct kvm_mmu_page
*sp
,
1578 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
1579 if (!vcpu
->arch
.update_pte
.largepage
||
1580 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
1581 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
1586 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
1587 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
1588 paging32_update_pte(vcpu
, sp
, spte
, new);
1590 paging64_update_pte(vcpu
, sp
, spte
, new);
1593 static bool need_remote_flush(u64 old
, u64
new)
1595 if (!is_shadow_present_pte(old
))
1597 if (!is_shadow_present_pte(new))
1599 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
1601 old
^= PT64_NX_MASK
;
1602 new ^= PT64_NX_MASK
;
1603 return (old
& ~new & PT64_PERM_MASK
) != 0;
1606 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
1608 if (need_remote_flush(old
, new))
1609 kvm_flush_remote_tlbs(vcpu
->kvm
);
1611 kvm_mmu_flush_tlb(vcpu
);
1614 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
1616 u64
*spte
= vcpu
->arch
.last_pte_updated
;
1618 return !!(spte
&& (*spte
& shadow_accessed_mask
));
1621 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1622 const u8
*new, int bytes
)
1629 vcpu
->arch
.update_pte
.largepage
= 0;
1631 if (bytes
!= 4 && bytes
!= 8)
1635 * Assume that the pte write on a page table of the same type
1636 * as the current vcpu paging mode. This is nearly always true
1637 * (might be false while changing modes). Note it is verified later
1641 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
1642 if ((bytes
== 4) && (gpa
% 4 == 0)) {
1643 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
1646 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
1647 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
1648 memcpy((void *)&gpte
, new, 8);
1651 if ((bytes
== 4) && (gpa
% 4 == 0))
1652 memcpy((void *)&gpte
, new, 4);
1654 if (!is_present_pte(gpte
))
1656 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1658 down_read(¤t
->mm
->mmap_sem
);
1659 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
1660 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1661 vcpu
->arch
.update_pte
.largepage
= 1;
1663 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1664 up_read(¤t
->mm
->mmap_sem
);
1666 if (is_error_pfn(pfn
)) {
1667 kvm_release_pfn_clean(pfn
);
1670 vcpu
->arch
.update_pte
.gfn
= gfn
;
1671 vcpu
->arch
.update_pte
.pfn
= pfn
;
1674 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
1675 const u8
*new, int bytes
)
1677 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1678 struct kvm_mmu_page
*sp
;
1679 struct hlist_node
*node
, *n
;
1680 struct hlist_head
*bucket
;
1684 unsigned offset
= offset_in_page(gpa
);
1686 unsigned page_offset
;
1687 unsigned misaligned
;
1694 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
1695 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
1696 spin_lock(&vcpu
->kvm
->mmu_lock
);
1697 kvm_mmu_free_some_pages(vcpu
);
1698 ++vcpu
->kvm
->stat
.mmu_pte_write
;
1699 kvm_mmu_audit(vcpu
, "pre pte write");
1700 if (gfn
== vcpu
->arch
.last_pt_write_gfn
1701 && !last_updated_pte_accessed(vcpu
)) {
1702 ++vcpu
->arch
.last_pt_write_count
;
1703 if (vcpu
->arch
.last_pt_write_count
>= 3)
1706 vcpu
->arch
.last_pt_write_gfn
= gfn
;
1707 vcpu
->arch
.last_pt_write_count
= 1;
1708 vcpu
->arch
.last_pte_updated
= NULL
;
1710 index
= kvm_page_table_hashfn(gfn
);
1711 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1712 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
1713 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
)
1715 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
1716 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
1717 misaligned
|= bytes
< 4;
1718 if (misaligned
|| flooded
) {
1720 * Misaligned accesses are too much trouble to fix
1721 * up; also, they usually indicate a page is not used
1724 * If we're seeing too many writes to a page,
1725 * it may no longer be a page table, or we may be
1726 * forking, in which case it is better to unmap the
1729 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
1730 gpa
, bytes
, sp
->role
.word
);
1731 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1732 ++vcpu
->kvm
->stat
.mmu_flooded
;
1735 page_offset
= offset
;
1736 level
= sp
->role
.level
;
1738 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
1739 page_offset
<<= 1; /* 32->64 */
1741 * A 32-bit pde maps 4MB while the shadow pdes map
1742 * only 2MB. So we need to double the offset again
1743 * and zap two pdes instead of one.
1745 if (level
== PT32_ROOT_LEVEL
) {
1746 page_offset
&= ~7; /* kill rounding error */
1750 quadrant
= page_offset
>> PAGE_SHIFT
;
1751 page_offset
&= ~PAGE_MASK
;
1752 if (quadrant
!= sp
->role
.quadrant
)
1755 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
1756 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
1758 r
= kvm_read_guest_atomic(vcpu
->kvm
,
1759 gpa
& ~(u64
)(pte_size
- 1),
1761 new = (const void *)&gentry
;
1767 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
1769 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
1770 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
1774 kvm_mmu_audit(vcpu
, "post pte write");
1775 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1776 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
1777 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
1778 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
1782 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
1787 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1789 spin_lock(&vcpu
->kvm
->mmu_lock
);
1790 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1791 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1795 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
1797 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
1798 struct kvm_mmu_page
*sp
;
1800 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
1801 struct kvm_mmu_page
, link
);
1802 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1803 ++vcpu
->kvm
->stat
.mmu_recycled
;
1807 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
1810 enum emulation_result er
;
1812 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
1821 r
= mmu_topup_memory_caches(vcpu
);
1825 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
1830 case EMULATE_DO_MMIO
:
1831 ++vcpu
->stat
.mmio_exits
;
1834 kvm_report_emulation_failure(vcpu
, "pagetable");
1842 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
1844 void kvm_enable_tdp(void)
1848 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
1850 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
1852 struct kvm_mmu_page
*sp
;
1854 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
1855 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
1856 struct kvm_mmu_page
, link
);
1857 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1860 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
1863 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
1870 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
1871 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1872 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
1874 vcpu
->kvm
->arch
.n_free_mmu_pages
=
1875 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
1877 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
1878 * Therefore we need to allocate shadow page tables in the first
1879 * 4GB of memory, which happens to fit the DMA32 zone.
1881 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
1884 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
1885 for (i
= 0; i
< 4; ++i
)
1886 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1891 free_mmu_pages(vcpu
);
1895 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
1898 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1900 return alloc_mmu_pages(vcpu
);
1903 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
1906 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1908 return init_kvm_mmu(vcpu
);
1911 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
1915 destroy_kvm_mmu(vcpu
);
1916 free_mmu_pages(vcpu
);
1917 mmu_free_memory_caches(vcpu
);
1920 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
1922 struct kvm_mmu_page
*sp
;
1924 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
1928 if (!test_bit(slot
, &sp
->slot_bitmap
))
1932 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1934 if (pt
[i
] & PT_WRITABLE_MASK
)
1935 pt
[i
] &= ~PT_WRITABLE_MASK
;
1939 void kvm_mmu_zap_all(struct kvm
*kvm
)
1941 struct kvm_mmu_page
*sp
, *node
;
1943 spin_lock(&kvm
->mmu_lock
);
1944 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
1945 kvm_mmu_zap_page(kvm
, sp
);
1946 spin_unlock(&kvm
->mmu_lock
);
1948 kvm_flush_remote_tlbs(kvm
);
1951 void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
1953 struct kvm_mmu_page
*page
;
1955 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1956 struct kvm_mmu_page
, link
);
1957 kvm_mmu_zap_page(kvm
, page
);
1960 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
1963 struct kvm
*kvm_freed
= NULL
;
1964 int cache_count
= 0;
1966 spin_lock(&kvm_lock
);
1968 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
1971 spin_lock(&kvm
->mmu_lock
);
1972 npages
= kvm
->arch
.n_alloc_mmu_pages
-
1973 kvm
->arch
.n_free_mmu_pages
;
1974 cache_count
+= npages
;
1975 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
1976 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
1982 spin_unlock(&kvm
->mmu_lock
);
1985 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
1987 spin_unlock(&kvm_lock
);
1992 static struct shrinker mmu_shrinker
= {
1993 .shrink
= mmu_shrink
,
1994 .seeks
= DEFAULT_SEEKS
* 10,
1997 static void mmu_destroy_caches(void)
1999 if (pte_chain_cache
)
2000 kmem_cache_destroy(pte_chain_cache
);
2001 if (rmap_desc_cache
)
2002 kmem_cache_destroy(rmap_desc_cache
);
2003 if (mmu_page_header_cache
)
2004 kmem_cache_destroy(mmu_page_header_cache
);
2007 void kvm_mmu_module_exit(void)
2009 mmu_destroy_caches();
2010 unregister_shrinker(&mmu_shrinker
);
2013 int kvm_mmu_module_init(void)
2015 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2016 sizeof(struct kvm_pte_chain
),
2018 if (!pte_chain_cache
)
2020 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2021 sizeof(struct kvm_rmap_desc
),
2023 if (!rmap_desc_cache
)
2026 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2027 sizeof(struct kvm_mmu_page
),
2029 if (!mmu_page_header_cache
)
2032 register_shrinker(&mmu_shrinker
);
2037 mmu_destroy_caches();
2042 * Caculate mmu pages needed for kvm.
2044 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2047 unsigned int nr_mmu_pages
;
2048 unsigned int nr_pages
= 0;
2050 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2051 nr_pages
+= kvm
->memslots
[i
].npages
;
2053 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2054 nr_mmu_pages
= max(nr_mmu_pages
,
2055 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2057 return nr_mmu_pages
;
2060 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2063 if (len
> buffer
->len
)
2068 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2073 ret
= pv_mmu_peek_buffer(buffer
, len
);
2078 buffer
->processed
+= len
;
2082 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2083 gpa_t addr
, gpa_t value
)
2088 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2091 r
= mmu_topup_memory_caches(vcpu
);
2095 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2101 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2103 kvm_x86_ops
->tlb_flush(vcpu
);
2107 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2109 spin_lock(&vcpu
->kvm
->mmu_lock
);
2110 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2111 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2115 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2116 struct kvm_pv_mmu_op_buffer
*buffer
)
2118 struct kvm_mmu_op_header
*header
;
2120 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2123 switch (header
->op
) {
2124 case KVM_MMU_OP_WRITE_PTE
: {
2125 struct kvm_mmu_op_write_pte
*wpte
;
2127 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2130 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2133 case KVM_MMU_OP_FLUSH_TLB
: {
2134 struct kvm_mmu_op_flush_tlb
*ftlb
;
2136 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2139 return kvm_pv_mmu_flush_tlb(vcpu
);
2141 case KVM_MMU_OP_RELEASE_PT
: {
2142 struct kvm_mmu_op_release_pt
*rpt
;
2144 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2147 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2153 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2154 gpa_t addr
, unsigned long *ret
)
2157 struct kvm_pv_mmu_op_buffer buffer
;
2159 buffer
.ptr
= buffer
.buf
;
2160 buffer
.len
= min_t(unsigned long, bytes
, sizeof buffer
.buf
);
2161 buffer
.processed
= 0;
2163 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
.buf
, buffer
.len
);
2167 while (buffer
.len
) {
2168 r
= kvm_pv_mmu_op_one(vcpu
, &buffer
);
2177 *ret
= buffer
.processed
;
2183 static const char *audit_msg
;
2185 static gva_t
canonicalize(gva_t gva
)
2187 #ifdef CONFIG_X86_64
2188 gva
= (long long)(gva
<< 16) >> 16;
2193 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2194 gva_t va
, int level
)
2196 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
2198 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
2200 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
2203 if (ent
== shadow_trap_nonpresent_pte
)
2206 va
= canonicalize(va
);
2208 if (ent
== shadow_notrap_nonpresent_pte
)
2209 printk(KERN_ERR
"audit: (%s) nontrapping pte"
2210 " in nonleaf level: levels %d gva %lx"
2211 " level %d pte %llx\n", audit_msg
,
2212 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
2214 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
2216 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
2217 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
2219 if (is_shadow_present_pte(ent
)
2220 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
2221 printk(KERN_ERR
"xx audit error: (%s) levels %d"
2222 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
2223 audit_msg
, vcpu
->arch
.mmu
.root_level
,
2225 is_shadow_present_pte(ent
));
2226 else if (ent
== shadow_notrap_nonpresent_pte
2227 && !is_error_hpa(hpa
))
2228 printk(KERN_ERR
"audit: (%s) notrap shadow,"
2229 " valid guest gva %lx\n", audit_msg
, va
);
2230 kvm_release_pfn_clean(pfn
);
2236 static void audit_mappings(struct kvm_vcpu
*vcpu
)
2240 if (vcpu
->arch
.mmu
.root_level
== 4)
2241 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
2243 for (i
= 0; i
< 4; ++i
)
2244 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
2245 audit_mappings_page(vcpu
,
2246 vcpu
->arch
.mmu
.pae_root
[i
],
2251 static int count_rmaps(struct kvm_vcpu
*vcpu
)
2256 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
2257 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
2258 struct kvm_rmap_desc
*d
;
2260 for (j
= 0; j
< m
->npages
; ++j
) {
2261 unsigned long *rmapp
= &m
->rmap
[j
];
2265 if (!(*rmapp
& 1)) {
2269 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
2271 for (k
= 0; k
< RMAP_EXT
; ++k
)
2272 if (d
->shadow_ptes
[k
])
2283 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
2286 struct kvm_mmu_page
*sp
;
2289 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2292 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
2295 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
2298 if (!(ent
& PT_PRESENT_MASK
))
2300 if (!(ent
& PT_WRITABLE_MASK
))
2308 static void audit_rmap(struct kvm_vcpu
*vcpu
)
2310 int n_rmap
= count_rmaps(vcpu
);
2311 int n_actual
= count_writable_mappings(vcpu
);
2313 if (n_rmap
!= n_actual
)
2314 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
2315 __func__
, audit_msg
, n_rmap
, n_actual
);
2318 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
2320 struct kvm_mmu_page
*sp
;
2321 struct kvm_memory_slot
*slot
;
2322 unsigned long *rmapp
;
2325 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2326 if (sp
->role
.metaphysical
)
2329 slot
= gfn_to_memslot(vcpu
->kvm
, sp
->gfn
);
2330 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
2331 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
2333 printk(KERN_ERR
"%s: (%s) shadow page has writable"
2334 " mappings: gfn %lx role %x\n",
2335 __func__
, audit_msg
, sp
->gfn
,
2340 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
2347 audit_write_protection(vcpu
);
2348 audit_mappings(vcpu
);