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)
70 module_param(dbg
, bool, 0644);
73 static int oos_shadow
= 1;
74 module_param(oos_shadow
, bool, 0644);
77 #define ASSERT(x) do { } while (0)
81 printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
82 __FILE__, __LINE__, #x); \
86 #define PT_FIRST_AVAIL_BITS_SHIFT 9
87 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
89 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
91 #define PT64_LEVEL_BITS 9
93 #define PT64_LEVEL_SHIFT(level) \
94 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
96 #define PT64_LEVEL_MASK(level) \
97 (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
99 #define PT64_INDEX(address, level)\
100 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
103 #define PT32_LEVEL_BITS 10
105 #define PT32_LEVEL_SHIFT(level) \
106 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
108 #define PT32_LEVEL_MASK(level) \
109 (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
111 #define PT32_INDEX(address, level)\
112 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
115 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
116 #define PT64_DIR_BASE_ADDR_MASK \
117 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
119 #define PT32_BASE_ADDR_MASK PAGE_MASK
120 #define PT32_DIR_BASE_ADDR_MASK \
121 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
123 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
126 #define PFERR_PRESENT_MASK (1U << 0)
127 #define PFERR_WRITE_MASK (1U << 1)
128 #define PFERR_USER_MASK (1U << 2)
129 #define PFERR_FETCH_MASK (1U << 4)
131 #define PT_DIRECTORY_LEVEL 2
132 #define PT_PAGE_TABLE_LEVEL 1
136 #define ACC_EXEC_MASK 1
137 #define ACC_WRITE_MASK PT_WRITABLE_MASK
138 #define ACC_USER_MASK PT_USER_MASK
139 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
141 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
143 struct kvm_rmap_desc
{
144 u64
*shadow_ptes
[RMAP_EXT
];
145 struct kvm_rmap_desc
*more
;
148 struct kvm_shadow_walk
{
149 int (*entry
)(struct kvm_shadow_walk
*walk
, struct kvm_vcpu
*vcpu
,
150 u64 addr
, u64
*spte
, int level
);
153 struct kvm_unsync_walk
{
154 int (*entry
) (struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
);
157 typedef int (*mmu_parent_walk_fn
) (struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
);
159 static struct kmem_cache
*pte_chain_cache
;
160 static struct kmem_cache
*rmap_desc_cache
;
161 static struct kmem_cache
*mmu_page_header_cache
;
163 static u64 __read_mostly shadow_trap_nonpresent_pte
;
164 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
165 static u64 __read_mostly shadow_base_present_pte
;
166 static u64 __read_mostly shadow_nx_mask
;
167 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
168 static u64 __read_mostly shadow_user_mask
;
169 static u64 __read_mostly shadow_accessed_mask
;
170 static u64 __read_mostly shadow_dirty_mask
;
171 static u64 __read_mostly shadow_mt_mask
;
173 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
175 shadow_trap_nonpresent_pte
= trap_pte
;
176 shadow_notrap_nonpresent_pte
= notrap_pte
;
178 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
180 void kvm_mmu_set_base_ptes(u64 base_pte
)
182 shadow_base_present_pte
= base_pte
;
184 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes
);
186 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
187 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
, u64 mt_mask
)
189 shadow_user_mask
= user_mask
;
190 shadow_accessed_mask
= accessed_mask
;
191 shadow_dirty_mask
= dirty_mask
;
192 shadow_nx_mask
= nx_mask
;
193 shadow_x_mask
= x_mask
;
194 shadow_mt_mask
= mt_mask
;
196 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
198 static int is_write_protection(struct kvm_vcpu
*vcpu
)
200 return vcpu
->arch
.cr0
& X86_CR0_WP
;
203 static int is_cpuid_PSE36(void)
208 static int is_nx(struct kvm_vcpu
*vcpu
)
210 return vcpu
->arch
.shadow_efer
& EFER_NX
;
213 static int is_present_pte(unsigned long pte
)
215 return pte
& PT_PRESENT_MASK
;
218 static int is_shadow_present_pte(u64 pte
)
220 return pte
!= shadow_trap_nonpresent_pte
221 && pte
!= shadow_notrap_nonpresent_pte
;
224 static int is_large_pte(u64 pte
)
226 return pte
& PT_PAGE_SIZE_MASK
;
229 static int is_writeble_pte(unsigned long pte
)
231 return pte
& PT_WRITABLE_MASK
;
234 static int is_dirty_pte(unsigned long pte
)
236 return pte
& shadow_dirty_mask
;
239 static int is_rmap_pte(u64 pte
)
241 return is_shadow_present_pte(pte
);
244 static pfn_t
spte_to_pfn(u64 pte
)
246 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
249 static gfn_t
pse36_gfn_delta(u32 gpte
)
251 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
253 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
256 static void set_shadow_pte(u64
*sptep
, u64 spte
)
259 set_64bit((unsigned long *)sptep
, spte
);
261 set_64bit((unsigned long long *)sptep
, spte
);
265 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
266 struct kmem_cache
*base_cache
, int min
)
270 if (cache
->nobjs
>= min
)
272 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
273 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
276 cache
->objects
[cache
->nobjs
++] = obj
;
281 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
284 kfree(mc
->objects
[--mc
->nobjs
]);
287 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
292 if (cache
->nobjs
>= min
)
294 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
295 page
= alloc_page(GFP_KERNEL
);
298 set_page_private(page
, 0);
299 cache
->objects
[cache
->nobjs
++] = page_address(page
);
304 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
307 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
310 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
314 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
318 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
322 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
325 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
326 mmu_page_header_cache
, 4);
331 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
333 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
334 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
335 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
336 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
339 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
345 p
= mc
->objects
[--mc
->nobjs
];
350 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
352 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
353 sizeof(struct kvm_pte_chain
));
356 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
361 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
363 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
364 sizeof(struct kvm_rmap_desc
));
367 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
373 * Return the pointer to the largepage write count for a given
374 * gfn, handling slots that are not large page aligned.
376 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
380 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
381 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
382 return &slot
->lpage_info
[idx
].write_count
;
385 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
389 gfn
= unalias_gfn(kvm
, gfn
);
390 write_count
= slot_largepage_idx(gfn
,
391 gfn_to_memslot_unaliased(kvm
, gfn
));
395 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
399 gfn
= unalias_gfn(kvm
, gfn
);
400 write_count
= slot_largepage_idx(gfn
,
401 gfn_to_memslot_unaliased(kvm
, gfn
));
403 WARN_ON(*write_count
< 0);
406 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
408 struct kvm_memory_slot
*slot
;
411 gfn
= unalias_gfn(kvm
, gfn
);
412 slot
= gfn_to_memslot_unaliased(kvm
, gfn
);
414 largepage_idx
= slot_largepage_idx(gfn
, slot
);
415 return *largepage_idx
;
421 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
423 struct vm_area_struct
*vma
;
427 addr
= gfn_to_hva(kvm
, gfn
);
428 if (kvm_is_error_hva(addr
))
431 down_read(¤t
->mm
->mmap_sem
);
432 vma
= find_vma(current
->mm
, addr
);
433 if (vma
&& is_vm_hugetlb_page(vma
))
435 up_read(¤t
->mm
->mmap_sem
);
440 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
442 struct kvm_memory_slot
*slot
;
444 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
447 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
450 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
451 if (slot
&& slot
->dirty_bitmap
)
458 * Take gfn and return the reverse mapping to it.
459 * Note: gfn must be unaliased before this function get called
462 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
464 struct kvm_memory_slot
*slot
;
467 slot
= gfn_to_memslot(kvm
, gfn
);
469 return &slot
->rmap
[gfn
- slot
->base_gfn
];
471 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
472 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
474 return &slot
->lpage_info
[idx
].rmap_pde
;
478 * Reverse mapping data structures:
480 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
481 * that points to page_address(page).
483 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
484 * containing more mappings.
486 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
488 struct kvm_mmu_page
*sp
;
489 struct kvm_rmap_desc
*desc
;
490 unsigned long *rmapp
;
493 if (!is_rmap_pte(*spte
))
495 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
496 sp
= page_header(__pa(spte
));
497 sp
->gfns
[spte
- sp
->spt
] = gfn
;
498 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
500 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
501 *rmapp
= (unsigned long)spte
;
502 } else if (!(*rmapp
& 1)) {
503 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
504 desc
= mmu_alloc_rmap_desc(vcpu
);
505 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
506 desc
->shadow_ptes
[1] = spte
;
507 *rmapp
= (unsigned long)desc
| 1;
509 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
510 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
511 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
513 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
514 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
517 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
519 desc
->shadow_ptes
[i
] = spte
;
523 static void rmap_desc_remove_entry(unsigned long *rmapp
,
524 struct kvm_rmap_desc
*desc
,
526 struct kvm_rmap_desc
*prev_desc
)
530 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
532 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
533 desc
->shadow_ptes
[j
] = NULL
;
536 if (!prev_desc
&& !desc
->more
)
537 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
540 prev_desc
->more
= desc
->more
;
542 *rmapp
= (unsigned long)desc
->more
| 1;
543 mmu_free_rmap_desc(desc
);
546 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
548 struct kvm_rmap_desc
*desc
;
549 struct kvm_rmap_desc
*prev_desc
;
550 struct kvm_mmu_page
*sp
;
552 unsigned long *rmapp
;
555 if (!is_rmap_pte(*spte
))
557 sp
= page_header(__pa(spte
));
558 pfn
= spte_to_pfn(*spte
);
559 if (*spte
& shadow_accessed_mask
)
560 kvm_set_pfn_accessed(pfn
);
561 if (is_writeble_pte(*spte
))
562 kvm_release_pfn_dirty(pfn
);
564 kvm_release_pfn_clean(pfn
);
565 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
567 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
569 } else if (!(*rmapp
& 1)) {
570 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
571 if ((u64
*)*rmapp
!= spte
) {
572 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
578 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
579 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
582 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
583 if (desc
->shadow_ptes
[i
] == spte
) {
584 rmap_desc_remove_entry(rmapp
,
596 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
598 struct kvm_rmap_desc
*desc
;
599 struct kvm_rmap_desc
*prev_desc
;
605 else if (!(*rmapp
& 1)) {
607 return (u64
*)*rmapp
;
610 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
614 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
615 if (prev_spte
== spte
)
616 return desc
->shadow_ptes
[i
];
617 prev_spte
= desc
->shadow_ptes
[i
];
624 static void rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
626 unsigned long *rmapp
;
628 int write_protected
= 0;
630 gfn
= unalias_gfn(kvm
, gfn
);
631 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
633 spte
= rmap_next(kvm
, rmapp
, NULL
);
636 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
637 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
638 if (is_writeble_pte(*spte
)) {
639 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
642 spte
= rmap_next(kvm
, rmapp
, spte
);
644 if (write_protected
) {
647 spte
= rmap_next(kvm
, rmapp
, NULL
);
648 pfn
= spte_to_pfn(*spte
);
649 kvm_set_pfn_dirty(pfn
);
652 /* check for huge page mappings */
653 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
654 spte
= rmap_next(kvm
, rmapp
, NULL
);
657 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
658 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
659 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
660 if (is_writeble_pte(*spte
)) {
661 rmap_remove(kvm
, spte
);
663 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
667 spte
= rmap_next(kvm
, rmapp
, spte
);
671 kvm_flush_remote_tlbs(kvm
);
674 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
677 int need_tlb_flush
= 0;
679 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
680 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
681 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
682 rmap_remove(kvm
, spte
);
683 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
686 return need_tlb_flush
;
689 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
690 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
))
696 * If mmap_sem isn't taken, we can look the memslots with only
697 * the mmu_lock by skipping over the slots with userspace_addr == 0.
699 for (i
= 0; i
< kvm
->nmemslots
; i
++) {
700 struct kvm_memory_slot
*memslot
= &kvm
->memslots
[i
];
701 unsigned long start
= memslot
->userspace_addr
;
704 /* mmu_lock protects userspace_addr */
708 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
709 if (hva
>= start
&& hva
< end
) {
710 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
711 retval
|= handler(kvm
, &memslot
->rmap
[gfn_offset
]);
712 retval
|= handler(kvm
,
713 &memslot
->lpage_info
[
715 KVM_PAGES_PER_HPAGE
].rmap_pde
);
722 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
724 return kvm_handle_hva(kvm
, hva
, kvm_unmap_rmapp
);
727 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
732 /* always return old for EPT */
733 if (!shadow_accessed_mask
)
736 spte
= rmap_next(kvm
, rmapp
, NULL
);
740 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
741 _young
= _spte
& PT_ACCESSED_MASK
;
744 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
746 spte
= rmap_next(kvm
, rmapp
, spte
);
751 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
753 return kvm_handle_hva(kvm
, hva
, kvm_age_rmapp
);
757 static int is_empty_shadow_page(u64
*spt
)
762 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
763 if (is_shadow_present_pte(*pos
)) {
764 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
772 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
774 ASSERT(is_empty_shadow_page(sp
->spt
));
776 __free_page(virt_to_page(sp
->spt
));
777 __free_page(virt_to_page(sp
->gfns
));
779 ++kvm
->arch
.n_free_mmu_pages
;
782 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
784 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
787 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
790 struct kvm_mmu_page
*sp
;
792 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
793 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
794 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
795 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
796 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
797 ASSERT(is_empty_shadow_page(sp
->spt
));
798 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
800 sp
->parent_pte
= parent_pte
;
801 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
805 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
806 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
808 struct kvm_pte_chain
*pte_chain
;
809 struct hlist_node
*node
;
814 if (!sp
->multimapped
) {
815 u64
*old
= sp
->parent_pte
;
818 sp
->parent_pte
= parent_pte
;
822 pte_chain
= mmu_alloc_pte_chain(vcpu
);
823 INIT_HLIST_HEAD(&sp
->parent_ptes
);
824 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
825 pte_chain
->parent_ptes
[0] = old
;
827 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
828 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
830 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
831 if (!pte_chain
->parent_ptes
[i
]) {
832 pte_chain
->parent_ptes
[i
] = parent_pte
;
836 pte_chain
= mmu_alloc_pte_chain(vcpu
);
838 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
839 pte_chain
->parent_ptes
[0] = parent_pte
;
842 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
845 struct kvm_pte_chain
*pte_chain
;
846 struct hlist_node
*node
;
849 if (!sp
->multimapped
) {
850 BUG_ON(sp
->parent_pte
!= parent_pte
);
851 sp
->parent_pte
= NULL
;
854 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
855 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
856 if (!pte_chain
->parent_ptes
[i
])
858 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
860 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
861 && pte_chain
->parent_ptes
[i
+ 1]) {
862 pte_chain
->parent_ptes
[i
]
863 = pte_chain
->parent_ptes
[i
+ 1];
866 pte_chain
->parent_ptes
[i
] = NULL
;
868 hlist_del(&pte_chain
->link
);
869 mmu_free_pte_chain(pte_chain
);
870 if (hlist_empty(&sp
->parent_ptes
)) {
872 sp
->parent_pte
= NULL
;
881 static void mmu_parent_walk(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
882 mmu_parent_walk_fn fn
)
884 struct kvm_pte_chain
*pte_chain
;
885 struct hlist_node
*node
;
886 struct kvm_mmu_page
*parent_sp
;
889 if (!sp
->multimapped
&& sp
->parent_pte
) {
890 parent_sp
= page_header(__pa(sp
->parent_pte
));
892 mmu_parent_walk(vcpu
, parent_sp
, fn
);
895 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
896 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
897 if (!pte_chain
->parent_ptes
[i
])
899 parent_sp
= page_header(__pa(pte_chain
->parent_ptes
[i
]));
901 mmu_parent_walk(vcpu
, parent_sp
, fn
);
905 static void kvm_mmu_update_unsync_bitmap(u64
*spte
)
908 struct kvm_mmu_page
*sp
= page_header(__pa(spte
));
910 index
= spte
- sp
->spt
;
911 __set_bit(index
, sp
->unsync_child_bitmap
);
912 sp
->unsync_children
= 1;
915 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page
*sp
)
917 struct kvm_pte_chain
*pte_chain
;
918 struct hlist_node
*node
;
924 if (!sp
->multimapped
) {
925 kvm_mmu_update_unsync_bitmap(sp
->parent_pte
);
929 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
930 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
931 if (!pte_chain
->parent_ptes
[i
])
933 kvm_mmu_update_unsync_bitmap(pte_chain
->parent_ptes
[i
]);
937 static int unsync_walk_fn(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
939 sp
->unsync_children
= 1;
940 kvm_mmu_update_parents_unsync(sp
);
944 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu
*vcpu
,
945 struct kvm_mmu_page
*sp
)
947 mmu_parent_walk(vcpu
, sp
, unsync_walk_fn
);
948 kvm_mmu_update_parents_unsync(sp
);
951 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
952 struct kvm_mmu_page
*sp
)
956 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
957 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
960 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
961 struct kvm_mmu_page
*sp
)
966 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
970 #define for_each_unsync_children(bitmap, idx) \
971 for (idx = find_first_bit(bitmap, 512); \
973 idx = find_next_bit(bitmap, 512, idx+1))
975 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
976 struct kvm_unsync_walk
*walker
)
980 if (!sp
->unsync_children
)
983 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
984 u64 ent
= sp
->spt
[i
];
986 if (is_shadow_present_pte(ent
)) {
987 struct kvm_mmu_page
*child
;
988 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
990 if (child
->unsync_children
) {
991 ret
= mmu_unsync_walk(child
, walker
);
994 __clear_bit(i
, sp
->unsync_child_bitmap
);
998 ret
= walker
->entry(child
, walker
);
999 __clear_bit(i
, sp
->unsync_child_bitmap
);
1006 if (find_first_bit(sp
->unsync_child_bitmap
, 512) == 512)
1007 sp
->unsync_children
= 0;
1012 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
1015 struct hlist_head
*bucket
;
1016 struct kvm_mmu_page
*sp
;
1017 struct hlist_node
*node
;
1019 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1020 index
= kvm_page_table_hashfn(gfn
);
1021 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1022 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
1023 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
1024 && !sp
->role
.invalid
) {
1025 pgprintk("%s: found role %x\n",
1026 __func__
, sp
->role
.word
);
1032 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1034 WARN_ON(!sp
->unsync
);
1036 --kvm
->stat
.mmu_unsync
;
1039 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
);
1041 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1043 if (sp
->role
.glevels
!= vcpu
->arch
.mmu
.root_level
) {
1044 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1048 rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1049 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1050 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1051 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1055 kvm_mmu_flush_tlb(vcpu
);
1059 struct sync_walker
{
1060 struct kvm_vcpu
*vcpu
;
1061 struct kvm_unsync_walk walker
;
1064 static int mmu_sync_fn(struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
)
1066 struct sync_walker
*sync_walk
= container_of(walk
, struct sync_walker
,
1068 struct kvm_vcpu
*vcpu
= sync_walk
->vcpu
;
1070 kvm_sync_page(vcpu
, sp
);
1071 return (need_resched() || spin_needbreak(&vcpu
->kvm
->mmu_lock
));
1074 static void mmu_sync_children(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1076 struct sync_walker walker
= {
1077 .walker
= { .entry
= mmu_sync_fn
, },
1081 while (mmu_unsync_walk(sp
, &walker
.walker
))
1082 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1085 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1093 union kvm_mmu_page_role role
;
1096 struct hlist_head
*bucket
;
1097 struct kvm_mmu_page
*sp
;
1098 struct hlist_node
*node
, *tmp
;
1101 role
.glevels
= vcpu
->arch
.mmu
.root_level
;
1103 role
.metaphysical
= metaphysical
;
1104 role
.access
= access
;
1105 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1106 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1107 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1108 role
.quadrant
= quadrant
;
1110 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
1112 index
= kvm_page_table_hashfn(gfn
);
1113 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1114 hlist_for_each_entry_safe(sp
, node
, tmp
, bucket
, hash_link
)
1115 if (sp
->gfn
== gfn
) {
1117 if (kvm_sync_page(vcpu
, sp
))
1120 if (sp
->role
.word
!= role
.word
)
1123 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1124 if (sp
->unsync_children
) {
1125 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
1126 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1128 pgprintk("%s: found\n", __func__
);
1131 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1132 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
1135 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
1138 hlist_add_head(&sp
->hash_link
, bucket
);
1139 if (!metaphysical
) {
1140 rmap_write_protect(vcpu
->kvm
, gfn
);
1141 account_shadowed(vcpu
->kvm
, gfn
);
1143 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1144 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1146 nonpaging_prefetch_page(vcpu
, sp
);
1150 static int walk_shadow(struct kvm_shadow_walk
*walker
,
1151 struct kvm_vcpu
*vcpu
, u64 addr
)
1159 shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1160 level
= vcpu
->arch
.mmu
.shadow_root_level
;
1161 if (level
== PT32E_ROOT_LEVEL
) {
1162 shadow_addr
= vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1163 shadow_addr
&= PT64_BASE_ADDR_MASK
;
1167 while (level
>= PT_PAGE_TABLE_LEVEL
) {
1168 index
= SHADOW_PT_INDEX(addr
, level
);
1169 sptep
= ((u64
*)__va(shadow_addr
)) + index
;
1170 r
= walker
->entry(walker
, vcpu
, addr
, sptep
, level
);
1173 shadow_addr
= *sptep
& PT64_BASE_ADDR_MASK
;
1179 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1180 struct kvm_mmu_page
*sp
)
1188 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1189 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1190 if (is_shadow_present_pte(pt
[i
]))
1191 rmap_remove(kvm
, &pt
[i
]);
1192 pt
[i
] = shadow_trap_nonpresent_pte
;
1197 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1200 if (is_shadow_present_pte(ent
)) {
1201 if (!is_large_pte(ent
)) {
1202 ent
&= PT64_BASE_ADDR_MASK
;
1203 mmu_page_remove_parent_pte(page_header(ent
),
1207 rmap_remove(kvm
, &pt
[i
]);
1210 pt
[i
] = shadow_trap_nonpresent_pte
;
1214 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1216 mmu_page_remove_parent_pte(sp
, parent_pte
);
1219 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1223 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
1225 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
1228 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1232 while (sp
->multimapped
|| sp
->parent_pte
) {
1233 if (!sp
->multimapped
)
1234 parent_pte
= sp
->parent_pte
;
1236 struct kvm_pte_chain
*chain
;
1238 chain
= container_of(sp
->parent_ptes
.first
,
1239 struct kvm_pte_chain
, link
);
1240 parent_pte
= chain
->parent_ptes
[0];
1242 BUG_ON(!parent_pte
);
1243 kvm_mmu_put_page(sp
, parent_pte
);
1244 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
1249 struct kvm_unsync_walk walker
;
1254 static int mmu_zap_fn(struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
)
1256 struct zap_walker
*zap_walk
= container_of(walk
, struct zap_walker
,
1258 kvm_mmu_zap_page(zap_walk
->kvm
, sp
);
1259 zap_walk
->zapped
= 1;
1263 static int mmu_zap_unsync_children(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1265 struct zap_walker walker
= {
1266 .walker
= { .entry
= mmu_zap_fn
, },
1271 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1273 mmu_unsync_walk(sp
, &walker
.walker
);
1274 return walker
.zapped
;
1277 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1280 ++kvm
->stat
.mmu_shadow_zapped
;
1281 ret
= mmu_zap_unsync_children(kvm
, sp
);
1282 kvm_mmu_page_unlink_children(kvm
, sp
);
1283 kvm_mmu_unlink_parents(kvm
, sp
);
1284 kvm_flush_remote_tlbs(kvm
);
1285 if (!sp
->role
.invalid
&& !sp
->role
.metaphysical
)
1286 unaccount_shadowed(kvm
, sp
->gfn
);
1288 kvm_unlink_unsync_page(kvm
, sp
);
1289 if (!sp
->root_count
) {
1290 hlist_del(&sp
->hash_link
);
1291 kvm_mmu_free_page(kvm
, sp
);
1293 sp
->role
.invalid
= 1;
1294 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1295 kvm_reload_remote_mmus(kvm
);
1297 kvm_mmu_reset_last_pte_updated(kvm
);
1302 * Changing the number of mmu pages allocated to the vm
1303 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1305 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
1308 * If we set the number of mmu pages to be smaller be than the
1309 * number of actived pages , we must to free some mmu pages before we
1313 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
1315 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
1316 - kvm
->arch
.n_free_mmu_pages
;
1318 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
1319 struct kvm_mmu_page
*page
;
1321 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1322 struct kvm_mmu_page
, link
);
1323 kvm_mmu_zap_page(kvm
, page
);
1326 kvm
->arch
.n_free_mmu_pages
= 0;
1329 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
1330 - kvm
->arch
.n_alloc_mmu_pages
;
1332 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
1335 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1338 struct hlist_head
*bucket
;
1339 struct kvm_mmu_page
*sp
;
1340 struct hlist_node
*node
, *n
;
1343 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1345 index
= kvm_page_table_hashfn(gfn
);
1346 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1347 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
1348 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
1349 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
1352 if (kvm_mmu_zap_page(kvm
, sp
))
1358 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1360 struct kvm_mmu_page
*sp
;
1362 while ((sp
= kvm_mmu_lookup_page(kvm
, gfn
)) != NULL
) {
1363 pgprintk("%s: zap %lx %x\n", __func__
, gfn
, sp
->role
.word
);
1364 kvm_mmu_zap_page(kvm
, sp
);
1368 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1370 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1371 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1373 __set_bit(slot
, sp
->slot_bitmap
);
1376 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1381 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1384 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1385 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1386 set_shadow_pte(&pt
[i
], shadow_trap_nonpresent_pte
);
1390 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1394 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1396 if (gpa
== UNMAPPED_GVA
)
1399 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1405 * The function is based on mtrr_type_lookup() in
1406 * arch/x86/kernel/cpu/mtrr/generic.c
1408 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1413 u8 prev_match
, curr_match
;
1414 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1416 if (!mtrr_state
->enabled
)
1419 /* Make end inclusive end, instead of exclusive */
1422 /* Look in fixed ranges. Just return the type as per start */
1423 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1426 if (start
< 0x80000) {
1428 idx
+= (start
>> 16);
1429 return mtrr_state
->fixed_ranges
[idx
];
1430 } else if (start
< 0xC0000) {
1432 idx
+= ((start
- 0x80000) >> 14);
1433 return mtrr_state
->fixed_ranges
[idx
];
1434 } else if (start
< 0x1000000) {
1436 idx
+= ((start
- 0xC0000) >> 12);
1437 return mtrr_state
->fixed_ranges
[idx
];
1442 * Look in variable ranges
1443 * Look of multiple ranges matching this address and pick type
1444 * as per MTRR precedence
1446 if (!(mtrr_state
->enabled
& 2))
1447 return mtrr_state
->def_type
;
1450 for (i
= 0; i
< num_var_ranges
; ++i
) {
1451 unsigned short start_state
, end_state
;
1453 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1456 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1457 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1458 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1459 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1461 start_state
= ((start
& mask
) == (base
& mask
));
1462 end_state
= ((end
& mask
) == (base
& mask
));
1463 if (start_state
!= end_state
)
1466 if ((start
& mask
) != (base
& mask
))
1469 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1470 if (prev_match
== 0xFF) {
1471 prev_match
= curr_match
;
1475 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1476 curr_match
== MTRR_TYPE_UNCACHABLE
)
1477 return MTRR_TYPE_UNCACHABLE
;
1479 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1480 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1481 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1482 curr_match
== MTRR_TYPE_WRBACK
)) {
1483 prev_match
= MTRR_TYPE_WRTHROUGH
;
1484 curr_match
= MTRR_TYPE_WRTHROUGH
;
1487 if (prev_match
!= curr_match
)
1488 return MTRR_TYPE_UNCACHABLE
;
1491 if (prev_match
!= 0xFF)
1494 return mtrr_state
->def_type
;
1497 static u8
get_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1501 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1502 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1503 if (mtrr
== 0xfe || mtrr
== 0xff)
1504 mtrr
= MTRR_TYPE_WRBACK
;
1508 static int kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1511 struct hlist_head
*bucket
;
1512 struct kvm_mmu_page
*s
;
1513 struct hlist_node
*node
, *n
;
1515 index
= kvm_page_table_hashfn(sp
->gfn
);
1516 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1517 /* don't unsync if pagetable is shadowed with multiple roles */
1518 hlist_for_each_entry_safe(s
, node
, n
, bucket
, hash_link
) {
1519 if (s
->gfn
!= sp
->gfn
|| s
->role
.metaphysical
)
1521 if (s
->role
.word
!= sp
->role
.word
)
1524 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1525 ++vcpu
->kvm
->stat
.mmu_unsync
;
1527 mmu_convert_notrap(sp
);
1531 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1534 struct kvm_mmu_page
*shadow
;
1536 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1538 if (shadow
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1542 if (can_unsync
&& oos_shadow
)
1543 return kvm_unsync_page(vcpu
, shadow
);
1549 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1550 unsigned pte_access
, int user_fault
,
1551 int write_fault
, int dirty
, int largepage
,
1552 gfn_t gfn
, pfn_t pfn
, bool speculative
,
1557 u64 mt_mask
= shadow_mt_mask
;
1560 * We don't set the accessed bit, since we sometimes want to see
1561 * whether the guest actually used the pte (in order to detect
1564 spte
= shadow_base_present_pte
| shadow_dirty_mask
;
1566 spte
|= shadow_accessed_mask
;
1568 pte_access
&= ~ACC_WRITE_MASK
;
1569 if (pte_access
& ACC_EXEC_MASK
)
1570 spte
|= shadow_x_mask
;
1572 spte
|= shadow_nx_mask
;
1573 if (pte_access
& ACC_USER_MASK
)
1574 spte
|= shadow_user_mask
;
1576 spte
|= PT_PAGE_SIZE_MASK
;
1578 mt_mask
= get_memory_type(vcpu
, gfn
) <<
1579 kvm_x86_ops
->get_mt_mask_shift();
1583 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1585 if ((pte_access
& ACC_WRITE_MASK
)
1586 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1588 if (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
)) {
1590 spte
= shadow_trap_nonpresent_pte
;
1594 spte
|= PT_WRITABLE_MASK
;
1596 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1597 pgprintk("%s: found shadow page for %lx, marking ro\n",
1600 pte_access
&= ~ACC_WRITE_MASK
;
1601 if (is_writeble_pte(spte
))
1602 spte
&= ~PT_WRITABLE_MASK
;
1606 if (pte_access
& ACC_WRITE_MASK
)
1607 mark_page_dirty(vcpu
->kvm
, gfn
);
1610 set_shadow_pte(shadow_pte
, spte
);
1614 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1615 unsigned pt_access
, unsigned pte_access
,
1616 int user_fault
, int write_fault
, int dirty
,
1617 int *ptwrite
, int largepage
, gfn_t gfn
,
1618 pfn_t pfn
, bool speculative
)
1620 int was_rmapped
= 0;
1621 int was_writeble
= is_writeble_pte(*shadow_pte
);
1623 pgprintk("%s: spte %llx access %x write_fault %d"
1624 " user_fault %d gfn %lx\n",
1625 __func__
, *shadow_pte
, pt_access
,
1626 write_fault
, user_fault
, gfn
);
1628 if (is_rmap_pte(*shadow_pte
)) {
1630 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1631 * the parent of the now unreachable PTE.
1633 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1634 struct kvm_mmu_page
*child
;
1635 u64 pte
= *shadow_pte
;
1637 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1638 mmu_page_remove_parent_pte(child
, shadow_pte
);
1639 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1640 pgprintk("hfn old %lx new %lx\n",
1641 spte_to_pfn(*shadow_pte
), pfn
);
1642 rmap_remove(vcpu
->kvm
, shadow_pte
);
1645 was_rmapped
= is_large_pte(*shadow_pte
);
1650 if (set_spte(vcpu
, shadow_pte
, pte_access
, user_fault
, write_fault
,
1651 dirty
, largepage
, gfn
, pfn
, speculative
, true)) {
1654 kvm_x86_ops
->tlb_flush(vcpu
);
1657 pgprintk("%s: setting spte %llx\n", __func__
, *shadow_pte
);
1658 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1659 is_large_pte(*shadow_pte
)? "2MB" : "4kB",
1660 is_present_pte(*shadow_pte
)?"RW":"R", gfn
,
1661 *shadow_pte
, shadow_pte
);
1662 if (!was_rmapped
&& is_large_pte(*shadow_pte
))
1663 ++vcpu
->kvm
->stat
.lpages
;
1665 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1667 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1668 if (!is_rmap_pte(*shadow_pte
))
1669 kvm_release_pfn_clean(pfn
);
1672 kvm_release_pfn_dirty(pfn
);
1674 kvm_release_pfn_clean(pfn
);
1677 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1678 vcpu
->arch
.last_pte_gfn
= gfn
;
1682 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1686 struct direct_shadow_walk
{
1687 struct kvm_shadow_walk walker
;
1694 static int direct_map_entry(struct kvm_shadow_walk
*_walk
,
1695 struct kvm_vcpu
*vcpu
,
1696 u64 addr
, u64
*sptep
, int level
)
1698 struct direct_shadow_walk
*walk
=
1699 container_of(_walk
, struct direct_shadow_walk
, walker
);
1700 struct kvm_mmu_page
*sp
;
1702 gfn_t gfn
= addr
>> PAGE_SHIFT
;
1704 if (level
== PT_PAGE_TABLE_LEVEL
1705 || (walk
->largepage
&& level
== PT_DIRECTORY_LEVEL
)) {
1706 mmu_set_spte(vcpu
, sptep
, ACC_ALL
, ACC_ALL
,
1707 0, walk
->write
, 1, &walk
->pt_write
,
1708 walk
->largepage
, gfn
, walk
->pfn
, false);
1709 ++vcpu
->stat
.pf_fixed
;
1713 if (*sptep
== shadow_trap_nonpresent_pte
) {
1714 pseudo_gfn
= (addr
& PT64_DIR_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1715 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, (gva_t
)addr
, level
- 1,
1718 pgprintk("nonpaging_map: ENOMEM\n");
1719 kvm_release_pfn_clean(walk
->pfn
);
1723 set_shadow_pte(sptep
,
1725 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1726 | shadow_user_mask
| shadow_x_mask
);
1731 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1732 int largepage
, gfn_t gfn
, pfn_t pfn
)
1735 struct direct_shadow_walk walker
= {
1736 .walker
= { .entry
= direct_map_entry
, },
1738 .largepage
= largepage
,
1743 r
= walk_shadow(&walker
.walker
, vcpu
, gfn
<< PAGE_SHIFT
);
1746 return walker
.pt_write
;
1749 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1754 unsigned long mmu_seq
;
1756 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1757 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1761 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1763 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1766 if (is_error_pfn(pfn
)) {
1767 kvm_release_pfn_clean(pfn
);
1771 spin_lock(&vcpu
->kvm
->mmu_lock
);
1772 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1774 kvm_mmu_free_some_pages(vcpu
);
1775 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
);
1776 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1782 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1783 kvm_release_pfn_clean(pfn
);
1788 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1791 struct kvm_mmu_page
*sp
;
1793 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1795 spin_lock(&vcpu
->kvm
->mmu_lock
);
1796 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1797 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1799 sp
= page_header(root
);
1801 if (!sp
->root_count
&& sp
->role
.invalid
)
1802 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1803 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1804 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1807 for (i
= 0; i
< 4; ++i
) {
1808 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1811 root
&= PT64_BASE_ADDR_MASK
;
1812 sp
= page_header(root
);
1814 if (!sp
->root_count
&& sp
->role
.invalid
)
1815 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1817 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1819 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1820 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1823 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1827 struct kvm_mmu_page
*sp
;
1828 int metaphysical
= 0;
1830 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1832 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1833 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1835 ASSERT(!VALID_PAGE(root
));
1838 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1839 PT64_ROOT_LEVEL
, metaphysical
,
1841 root
= __pa(sp
->spt
);
1843 vcpu
->arch
.mmu
.root_hpa
= root
;
1846 metaphysical
= !is_paging(vcpu
);
1849 for (i
= 0; i
< 4; ++i
) {
1850 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1852 ASSERT(!VALID_PAGE(root
));
1853 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1854 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1855 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1858 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1859 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1861 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1862 PT32_ROOT_LEVEL
, metaphysical
,
1864 root
= __pa(sp
->spt
);
1866 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1868 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1871 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
1874 struct kvm_mmu_page
*sp
;
1876 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1878 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1879 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1880 sp
= page_header(root
);
1881 mmu_sync_children(vcpu
, sp
);
1884 for (i
= 0; i
< 4; ++i
) {
1885 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1888 root
&= PT64_BASE_ADDR_MASK
;
1889 sp
= page_header(root
);
1890 mmu_sync_children(vcpu
, sp
);
1895 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
1897 spin_lock(&vcpu
->kvm
->mmu_lock
);
1898 mmu_sync_roots(vcpu
);
1899 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1902 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
1907 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
1913 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
1914 r
= mmu_topup_memory_caches(vcpu
);
1919 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1921 gfn
= gva
>> PAGE_SHIFT
;
1923 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
1924 error_code
& PFERR_WRITE_MASK
, gfn
);
1927 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
1933 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
1934 unsigned long mmu_seq
;
1937 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
1939 r
= mmu_topup_memory_caches(vcpu
);
1943 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1944 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1947 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1949 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1950 if (is_error_pfn(pfn
)) {
1951 kvm_release_pfn_clean(pfn
);
1954 spin_lock(&vcpu
->kvm
->mmu_lock
);
1955 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1957 kvm_mmu_free_some_pages(vcpu
);
1958 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
1959 largepage
, gfn
, pfn
);
1960 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1965 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1966 kvm_release_pfn_clean(pfn
);
1970 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
1972 mmu_free_roots(vcpu
);
1975 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
1977 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
1979 context
->new_cr3
= nonpaging_new_cr3
;
1980 context
->page_fault
= nonpaging_page_fault
;
1981 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
1982 context
->free
= nonpaging_free
;
1983 context
->prefetch_page
= nonpaging_prefetch_page
;
1984 context
->sync_page
= nonpaging_sync_page
;
1985 context
->invlpg
= nonpaging_invlpg
;
1986 context
->root_level
= 0;
1987 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
1988 context
->root_hpa
= INVALID_PAGE
;
1992 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
1994 ++vcpu
->stat
.tlb_flush
;
1995 kvm_x86_ops
->tlb_flush(vcpu
);
1998 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2000 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
2001 mmu_free_roots(vcpu
);
2004 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2008 kvm_inject_page_fault(vcpu
, addr
, err_code
);
2011 static void paging_free(struct kvm_vcpu
*vcpu
)
2013 nonpaging_free(vcpu
);
2017 #include "paging_tmpl.h"
2021 #include "paging_tmpl.h"
2024 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
2026 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2028 ASSERT(is_pae(vcpu
));
2029 context
->new_cr3
= paging_new_cr3
;
2030 context
->page_fault
= paging64_page_fault
;
2031 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2032 context
->prefetch_page
= paging64_prefetch_page
;
2033 context
->sync_page
= paging64_sync_page
;
2034 context
->invlpg
= paging64_invlpg
;
2035 context
->free
= paging_free
;
2036 context
->root_level
= level
;
2037 context
->shadow_root_level
= level
;
2038 context
->root_hpa
= INVALID_PAGE
;
2042 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
2044 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
2047 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
2049 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2051 context
->new_cr3
= paging_new_cr3
;
2052 context
->page_fault
= paging32_page_fault
;
2053 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2054 context
->free
= paging_free
;
2055 context
->prefetch_page
= paging32_prefetch_page
;
2056 context
->sync_page
= paging32_sync_page
;
2057 context
->invlpg
= paging32_invlpg
;
2058 context
->root_level
= PT32_ROOT_LEVEL
;
2059 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2060 context
->root_hpa
= INVALID_PAGE
;
2064 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
2066 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
2069 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2071 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2073 context
->new_cr3
= nonpaging_new_cr3
;
2074 context
->page_fault
= tdp_page_fault
;
2075 context
->free
= nonpaging_free
;
2076 context
->prefetch_page
= nonpaging_prefetch_page
;
2077 context
->sync_page
= nonpaging_sync_page
;
2078 context
->invlpg
= nonpaging_invlpg
;
2079 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2080 context
->root_hpa
= INVALID_PAGE
;
2082 if (!is_paging(vcpu
)) {
2083 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2084 context
->root_level
= 0;
2085 } else if (is_long_mode(vcpu
)) {
2086 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2087 context
->root_level
= PT64_ROOT_LEVEL
;
2088 } else if (is_pae(vcpu
)) {
2089 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2090 context
->root_level
= PT32E_ROOT_LEVEL
;
2092 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2093 context
->root_level
= PT32_ROOT_LEVEL
;
2099 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2102 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2104 if (!is_paging(vcpu
))
2105 return nonpaging_init_context(vcpu
);
2106 else if (is_long_mode(vcpu
))
2107 return paging64_init_context(vcpu
);
2108 else if (is_pae(vcpu
))
2109 return paging32E_init_context(vcpu
);
2111 return paging32_init_context(vcpu
);
2114 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
2116 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2119 return init_kvm_tdp_mmu(vcpu
);
2121 return init_kvm_softmmu(vcpu
);
2124 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
2127 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
2128 vcpu
->arch
.mmu
.free(vcpu
);
2129 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2133 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
2135 destroy_kvm_mmu(vcpu
);
2136 return init_kvm_mmu(vcpu
);
2138 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
2140 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
2144 r
= mmu_topup_memory_caches(vcpu
);
2147 spin_lock(&vcpu
->kvm
->mmu_lock
);
2148 kvm_mmu_free_some_pages(vcpu
);
2149 mmu_alloc_roots(vcpu
);
2150 mmu_sync_roots(vcpu
);
2151 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2152 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
2153 kvm_mmu_flush_tlb(vcpu
);
2157 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
2159 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
2161 mmu_free_roots(vcpu
);
2164 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
2165 struct kvm_mmu_page
*sp
,
2169 struct kvm_mmu_page
*child
;
2172 if (is_shadow_present_pte(pte
)) {
2173 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
2175 rmap_remove(vcpu
->kvm
, spte
);
2177 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2178 mmu_page_remove_parent_pte(child
, spte
);
2181 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
2182 if (is_large_pte(pte
))
2183 --vcpu
->kvm
->stat
.lpages
;
2186 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
2187 struct kvm_mmu_page
*sp
,
2191 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
2192 if (!vcpu
->arch
.update_pte
.largepage
||
2193 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2194 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
2199 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
2200 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
2201 paging32_update_pte(vcpu
, sp
, spte
, new);
2203 paging64_update_pte(vcpu
, sp
, spte
, new);
2206 static bool need_remote_flush(u64 old
, u64
new)
2208 if (!is_shadow_present_pte(old
))
2210 if (!is_shadow_present_pte(new))
2212 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
2214 old
^= PT64_NX_MASK
;
2215 new ^= PT64_NX_MASK
;
2216 return (old
& ~new & PT64_PERM_MASK
) != 0;
2219 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
2221 if (need_remote_flush(old
, new))
2222 kvm_flush_remote_tlbs(vcpu
->kvm
);
2224 kvm_mmu_flush_tlb(vcpu
);
2227 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
2229 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2231 return !!(spte
&& (*spte
& shadow_accessed_mask
));
2234 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2235 const u8
*new, int bytes
)
2242 vcpu
->arch
.update_pte
.largepage
= 0;
2244 if (bytes
!= 4 && bytes
!= 8)
2248 * Assume that the pte write on a page table of the same type
2249 * as the current vcpu paging mode. This is nearly always true
2250 * (might be false while changing modes). Note it is verified later
2254 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2255 if ((bytes
== 4) && (gpa
% 4 == 0)) {
2256 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
2259 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
2260 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
2261 memcpy((void *)&gpte
, new, 8);
2264 if ((bytes
== 4) && (gpa
% 4 == 0))
2265 memcpy((void *)&gpte
, new, 4);
2267 if (!is_present_pte(gpte
))
2269 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
2271 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
2272 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2273 vcpu
->arch
.update_pte
.largepage
= 1;
2275 vcpu
->arch
.update_pte
.mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2277 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2279 if (is_error_pfn(pfn
)) {
2280 kvm_release_pfn_clean(pfn
);
2283 vcpu
->arch
.update_pte
.gfn
= gfn
;
2284 vcpu
->arch
.update_pte
.pfn
= pfn
;
2287 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2289 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2292 && vcpu
->arch
.last_pte_gfn
== gfn
2293 && shadow_accessed_mask
2294 && !(*spte
& shadow_accessed_mask
)
2295 && is_shadow_present_pte(*spte
))
2296 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
2299 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2300 const u8
*new, int bytes
)
2302 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2303 struct kvm_mmu_page
*sp
;
2304 struct hlist_node
*node
, *n
;
2305 struct hlist_head
*bucket
;
2309 unsigned offset
= offset_in_page(gpa
);
2311 unsigned page_offset
;
2312 unsigned misaligned
;
2319 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
2320 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
2321 spin_lock(&vcpu
->kvm
->mmu_lock
);
2322 kvm_mmu_access_page(vcpu
, gfn
);
2323 kvm_mmu_free_some_pages(vcpu
);
2324 ++vcpu
->kvm
->stat
.mmu_pte_write
;
2325 kvm_mmu_audit(vcpu
, "pre pte write");
2326 if (gfn
== vcpu
->arch
.last_pt_write_gfn
2327 && !last_updated_pte_accessed(vcpu
)) {
2328 ++vcpu
->arch
.last_pt_write_count
;
2329 if (vcpu
->arch
.last_pt_write_count
>= 3)
2332 vcpu
->arch
.last_pt_write_gfn
= gfn
;
2333 vcpu
->arch
.last_pt_write_count
= 1;
2334 vcpu
->arch
.last_pte_updated
= NULL
;
2336 index
= kvm_page_table_hashfn(gfn
);
2337 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
2338 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
2339 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
|| sp
->role
.invalid
)
2341 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
2342 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
2343 misaligned
|= bytes
< 4;
2344 if (misaligned
|| flooded
) {
2346 * Misaligned accesses are too much trouble to fix
2347 * up; also, they usually indicate a page is not used
2350 * If we're seeing too many writes to a page,
2351 * it may no longer be a page table, or we may be
2352 * forking, in which case it is better to unmap the
2355 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2356 gpa
, bytes
, sp
->role
.word
);
2357 if (kvm_mmu_zap_page(vcpu
->kvm
, sp
))
2359 ++vcpu
->kvm
->stat
.mmu_flooded
;
2362 page_offset
= offset
;
2363 level
= sp
->role
.level
;
2365 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2366 page_offset
<<= 1; /* 32->64 */
2368 * A 32-bit pde maps 4MB while the shadow pdes map
2369 * only 2MB. So we need to double the offset again
2370 * and zap two pdes instead of one.
2372 if (level
== PT32_ROOT_LEVEL
) {
2373 page_offset
&= ~7; /* kill rounding error */
2377 quadrant
= page_offset
>> PAGE_SHIFT
;
2378 page_offset
&= ~PAGE_MASK
;
2379 if (quadrant
!= sp
->role
.quadrant
)
2382 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
2383 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
2385 r
= kvm_read_guest_atomic(vcpu
->kvm
,
2386 gpa
& ~(u64
)(pte_size
- 1),
2388 new = (const void *)&gentry
;
2394 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
2396 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
2397 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
2401 kvm_mmu_audit(vcpu
, "post pte write");
2402 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2403 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
2404 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
2405 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2409 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
2414 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
2416 spin_lock(&vcpu
->kvm
->mmu_lock
);
2417 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
2418 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2421 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
2423 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
2425 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
2426 struct kvm_mmu_page
*sp
;
2428 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
2429 struct kvm_mmu_page
, link
);
2430 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2431 ++vcpu
->kvm
->stat
.mmu_recycled
;
2435 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
2438 enum emulation_result er
;
2440 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
2449 r
= mmu_topup_memory_caches(vcpu
);
2453 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
2458 case EMULATE_DO_MMIO
:
2459 ++vcpu
->stat
.mmio_exits
;
2462 kvm_report_emulation_failure(vcpu
, "pagetable");
2470 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
2472 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
2474 spin_lock(&vcpu
->kvm
->mmu_lock
);
2475 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
2476 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2477 kvm_mmu_flush_tlb(vcpu
);
2478 ++vcpu
->stat
.invlpg
;
2480 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
2482 void kvm_enable_tdp(void)
2486 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
2488 void kvm_disable_tdp(void)
2490 tdp_enabled
= false;
2492 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
2494 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
2496 struct kvm_mmu_page
*sp
;
2498 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
2499 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
2500 struct kvm_mmu_page
, link
);
2501 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2504 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
2507 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
2514 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
2515 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2516 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
2518 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2519 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
2521 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2522 * Therefore we need to allocate shadow page tables in the first
2523 * 4GB of memory, which happens to fit the DMA32 zone.
2525 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
2528 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
2529 for (i
= 0; i
< 4; ++i
)
2530 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2535 free_mmu_pages(vcpu
);
2539 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
2542 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2544 return alloc_mmu_pages(vcpu
);
2547 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
2550 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2552 return init_kvm_mmu(vcpu
);
2555 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
2559 destroy_kvm_mmu(vcpu
);
2560 free_mmu_pages(vcpu
);
2561 mmu_free_memory_caches(vcpu
);
2564 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
2566 struct kvm_mmu_page
*sp
;
2568 spin_lock(&kvm
->mmu_lock
);
2569 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
2573 if (!test_bit(slot
, sp
->slot_bitmap
))
2577 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
2579 if (pt
[i
] & PT_WRITABLE_MASK
)
2580 pt
[i
] &= ~PT_WRITABLE_MASK
;
2582 kvm_flush_remote_tlbs(kvm
);
2583 spin_unlock(&kvm
->mmu_lock
);
2586 void kvm_mmu_zap_all(struct kvm
*kvm
)
2588 struct kvm_mmu_page
*sp
, *node
;
2590 spin_lock(&kvm
->mmu_lock
);
2591 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
2592 if (kvm_mmu_zap_page(kvm
, sp
))
2593 node
= container_of(kvm
->arch
.active_mmu_pages
.next
,
2594 struct kvm_mmu_page
, link
);
2595 spin_unlock(&kvm
->mmu_lock
);
2597 kvm_flush_remote_tlbs(kvm
);
2600 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
2602 struct kvm_mmu_page
*page
;
2604 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
2605 struct kvm_mmu_page
, link
);
2606 kvm_mmu_zap_page(kvm
, page
);
2609 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
2612 struct kvm
*kvm_freed
= NULL
;
2613 int cache_count
= 0;
2615 spin_lock(&kvm_lock
);
2617 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
2620 if (!down_read_trylock(&kvm
->slots_lock
))
2622 spin_lock(&kvm
->mmu_lock
);
2623 npages
= kvm
->arch
.n_alloc_mmu_pages
-
2624 kvm
->arch
.n_free_mmu_pages
;
2625 cache_count
+= npages
;
2626 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
2627 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
2633 spin_unlock(&kvm
->mmu_lock
);
2634 up_read(&kvm
->slots_lock
);
2637 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
2639 spin_unlock(&kvm_lock
);
2644 static struct shrinker mmu_shrinker
= {
2645 .shrink
= mmu_shrink
,
2646 .seeks
= DEFAULT_SEEKS
* 10,
2649 static void mmu_destroy_caches(void)
2651 if (pte_chain_cache
)
2652 kmem_cache_destroy(pte_chain_cache
);
2653 if (rmap_desc_cache
)
2654 kmem_cache_destroy(rmap_desc_cache
);
2655 if (mmu_page_header_cache
)
2656 kmem_cache_destroy(mmu_page_header_cache
);
2659 void kvm_mmu_module_exit(void)
2661 mmu_destroy_caches();
2662 unregister_shrinker(&mmu_shrinker
);
2665 int kvm_mmu_module_init(void)
2667 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2668 sizeof(struct kvm_pte_chain
),
2670 if (!pte_chain_cache
)
2672 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2673 sizeof(struct kvm_rmap_desc
),
2675 if (!rmap_desc_cache
)
2678 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2679 sizeof(struct kvm_mmu_page
),
2681 if (!mmu_page_header_cache
)
2684 register_shrinker(&mmu_shrinker
);
2689 mmu_destroy_caches();
2694 * Caculate mmu pages needed for kvm.
2696 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2699 unsigned int nr_mmu_pages
;
2700 unsigned int nr_pages
= 0;
2702 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2703 nr_pages
+= kvm
->memslots
[i
].npages
;
2705 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2706 nr_mmu_pages
= max(nr_mmu_pages
,
2707 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2709 return nr_mmu_pages
;
2712 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2715 if (len
> buffer
->len
)
2720 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2725 ret
= pv_mmu_peek_buffer(buffer
, len
);
2730 buffer
->processed
+= len
;
2734 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2735 gpa_t addr
, gpa_t value
)
2740 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2743 r
= mmu_topup_memory_caches(vcpu
);
2747 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2753 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2755 kvm_x86_ops
->tlb_flush(vcpu
);
2756 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
2760 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2762 spin_lock(&vcpu
->kvm
->mmu_lock
);
2763 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2764 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2768 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2769 struct kvm_pv_mmu_op_buffer
*buffer
)
2771 struct kvm_mmu_op_header
*header
;
2773 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2776 switch (header
->op
) {
2777 case KVM_MMU_OP_WRITE_PTE
: {
2778 struct kvm_mmu_op_write_pte
*wpte
;
2780 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2783 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2786 case KVM_MMU_OP_FLUSH_TLB
: {
2787 struct kvm_mmu_op_flush_tlb
*ftlb
;
2789 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2792 return kvm_pv_mmu_flush_tlb(vcpu
);
2794 case KVM_MMU_OP_RELEASE_PT
: {
2795 struct kvm_mmu_op_release_pt
*rpt
;
2797 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2800 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2806 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2807 gpa_t addr
, unsigned long *ret
)
2810 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
2812 buffer
->ptr
= buffer
->buf
;
2813 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
2814 buffer
->processed
= 0;
2816 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
2820 while (buffer
->len
) {
2821 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
2830 *ret
= buffer
->processed
;
2836 static const char *audit_msg
;
2838 static gva_t
canonicalize(gva_t gva
)
2840 #ifdef CONFIG_X86_64
2841 gva
= (long long)(gva
<< 16) >> 16;
2846 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2847 gva_t va
, int level
)
2849 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
2851 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
2853 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
2856 if (ent
== shadow_trap_nonpresent_pte
)
2859 va
= canonicalize(va
);
2861 if (ent
== shadow_notrap_nonpresent_pte
)
2862 printk(KERN_ERR
"audit: (%s) nontrapping pte"
2863 " in nonleaf level: levels %d gva %lx"
2864 " level %d pte %llx\n", audit_msg
,
2865 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
2867 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
2869 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
2870 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
2872 if (is_shadow_present_pte(ent
)
2873 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
2874 printk(KERN_ERR
"xx audit error: (%s) levels %d"
2875 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
2876 audit_msg
, vcpu
->arch
.mmu
.root_level
,
2878 is_shadow_present_pte(ent
));
2879 else if (ent
== shadow_notrap_nonpresent_pte
2880 && !is_error_hpa(hpa
))
2881 printk(KERN_ERR
"audit: (%s) notrap shadow,"
2882 " valid guest gva %lx\n", audit_msg
, va
);
2883 kvm_release_pfn_clean(pfn
);
2889 static void audit_mappings(struct kvm_vcpu
*vcpu
)
2893 if (vcpu
->arch
.mmu
.root_level
== 4)
2894 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
2896 for (i
= 0; i
< 4; ++i
)
2897 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
2898 audit_mappings_page(vcpu
,
2899 vcpu
->arch
.mmu
.pae_root
[i
],
2904 static int count_rmaps(struct kvm_vcpu
*vcpu
)
2909 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
2910 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
2911 struct kvm_rmap_desc
*d
;
2913 for (j
= 0; j
< m
->npages
; ++j
) {
2914 unsigned long *rmapp
= &m
->rmap
[j
];
2918 if (!(*rmapp
& 1)) {
2922 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
2924 for (k
= 0; k
< RMAP_EXT
; ++k
)
2925 if (d
->shadow_ptes
[k
])
2936 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
2939 struct kvm_mmu_page
*sp
;
2942 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2945 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
2948 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
2951 if (!(ent
& PT_PRESENT_MASK
))
2953 if (!(ent
& PT_WRITABLE_MASK
))
2961 static void audit_rmap(struct kvm_vcpu
*vcpu
)
2963 int n_rmap
= count_rmaps(vcpu
);
2964 int n_actual
= count_writable_mappings(vcpu
);
2966 if (n_rmap
!= n_actual
)
2967 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
2968 __func__
, audit_msg
, n_rmap
, n_actual
);
2971 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
2973 struct kvm_mmu_page
*sp
;
2974 struct kvm_memory_slot
*slot
;
2975 unsigned long *rmapp
;
2978 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
2979 if (sp
->role
.metaphysical
)
2982 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
2983 slot
= gfn_to_memslot_unaliased(vcpu
->kvm
, sp
->gfn
);
2984 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
2986 printk(KERN_ERR
"%s: (%s) shadow page has writable"
2987 " mappings: gfn %lx role %x\n",
2988 __func__
, audit_msg
, sp
->gfn
,
2993 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
3000 audit_write_protection(vcpu
);
3001 audit_mappings(vcpu
);