2 * Kernel-based Virtual Machine driver for Linux
4 * This module enables machines with Intel VT-x extensions to run virtual
5 * machines without emulation or binary translation.
9 * Copyright (C) 2006 Qumranet, Inc.
12 * Yaniv Kamay <yaniv@qumranet.com>
13 * Avi Kivity <avi@qumranet.com>
15 * This work is licensed under the terms of the GNU GPL, version 2. See
16 * the COPYING file in the top-level directory.
21 #include "kvm_cache_regs.h"
23 #include <linux/kvm_host.h>
24 #include <linux/types.h>
25 #include <linux/string.h>
27 #include <linux/highmem.h>
28 #include <linux/module.h>
29 #include <linux/swap.h>
30 #include <linux/hugetlb.h>
31 #include <linux/compiler.h>
34 #include <asm/cmpxchg.h>
39 * When setting this variable to true it enables Two-Dimensional-Paging
40 * where the hardware walks 2 page tables:
41 * 1. the guest-virtual to guest-physical
42 * 2. while doing 1. it walks guest-physical to host-physical
43 * If the hardware supports that we don't need to do shadow paging.
45 bool tdp_enabled
= false;
52 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
);
54 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
) {}
59 #define pgprintk(x...) do { if (dbg) printk(x); } while (0)
60 #define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
64 #define pgprintk(x...) do { } while (0)
65 #define rmap_printk(x...) do { } while (0)
69 #if defined(MMU_DEBUG) || defined(AUDIT)
71 module_param(dbg
, bool, 0644);
74 static int oos_shadow
= 1;
75 module_param(oos_shadow
, bool, 0644);
78 #define ASSERT(x) do { } while (0)
82 printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
83 __FILE__, __LINE__, #x); \
87 #define PT_FIRST_AVAIL_BITS_SHIFT 9
88 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
90 #define VALID_PAGE(x) ((x) != INVALID_PAGE)
92 #define PT64_LEVEL_BITS 9
94 #define PT64_LEVEL_SHIFT(level) \
95 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
97 #define PT64_LEVEL_MASK(level) \
98 (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level))
100 #define PT64_INDEX(address, level)\
101 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
104 #define PT32_LEVEL_BITS 10
106 #define PT32_LEVEL_SHIFT(level) \
107 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
109 #define PT32_LEVEL_MASK(level) \
110 (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level))
112 #define PT32_INDEX(address, level)\
113 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
116 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
117 #define PT64_DIR_BASE_ADDR_MASK \
118 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
120 #define PT32_BASE_ADDR_MASK PAGE_MASK
121 #define PT32_DIR_BASE_ADDR_MASK \
122 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
124 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
127 #define PFERR_PRESENT_MASK (1U << 0)
128 #define PFERR_WRITE_MASK (1U << 1)
129 #define PFERR_USER_MASK (1U << 2)
130 #define PFERR_RSVD_MASK (1U << 3)
131 #define PFERR_FETCH_MASK (1U << 4)
133 #define PT_DIRECTORY_LEVEL 2
134 #define PT_PAGE_TABLE_LEVEL 1
138 #define ACC_EXEC_MASK 1
139 #define ACC_WRITE_MASK PT_WRITABLE_MASK
140 #define ACC_USER_MASK PT_USER_MASK
141 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
143 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
145 struct kvm_rmap_desc
{
146 u64
*sptes
[RMAP_EXT
];
147 struct kvm_rmap_desc
*more
;
150 struct kvm_shadow_walk_iterator
{
158 #define for_each_shadow_entry(_vcpu, _addr, _walker) \
159 for (shadow_walk_init(&(_walker), _vcpu, _addr); \
160 shadow_walk_okay(&(_walker)); \
161 shadow_walk_next(&(_walker)))
164 struct kvm_unsync_walk
{
165 int (*entry
) (struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
);
168 typedef int (*mmu_parent_walk_fn
) (struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
);
170 static struct kmem_cache
*pte_chain_cache
;
171 static struct kmem_cache
*rmap_desc_cache
;
172 static struct kmem_cache
*mmu_page_header_cache
;
174 static u64 __read_mostly shadow_trap_nonpresent_pte
;
175 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
176 static u64 __read_mostly shadow_base_present_pte
;
177 static u64 __read_mostly shadow_nx_mask
;
178 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
179 static u64 __read_mostly shadow_user_mask
;
180 static u64 __read_mostly shadow_accessed_mask
;
181 static u64 __read_mostly shadow_dirty_mask
;
183 static inline u64
rsvd_bits(int s
, int e
)
185 return ((1ULL << (e
- s
+ 1)) - 1) << s
;
188 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
190 shadow_trap_nonpresent_pte
= trap_pte
;
191 shadow_notrap_nonpresent_pte
= notrap_pte
;
193 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
195 void kvm_mmu_set_base_ptes(u64 base_pte
)
197 shadow_base_present_pte
= base_pte
;
199 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes
);
201 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
202 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
)
204 shadow_user_mask
= user_mask
;
205 shadow_accessed_mask
= accessed_mask
;
206 shadow_dirty_mask
= dirty_mask
;
207 shadow_nx_mask
= nx_mask
;
208 shadow_x_mask
= x_mask
;
210 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
212 static int is_write_protection(struct kvm_vcpu
*vcpu
)
214 return vcpu
->arch
.cr0
& X86_CR0_WP
;
217 static int is_cpuid_PSE36(void)
222 static int is_nx(struct kvm_vcpu
*vcpu
)
224 return vcpu
->arch
.shadow_efer
& EFER_NX
;
227 static int is_shadow_present_pte(u64 pte
)
229 return pte
!= shadow_trap_nonpresent_pte
230 && pte
!= shadow_notrap_nonpresent_pte
;
233 static int is_large_pte(u64 pte
)
235 return pte
& PT_PAGE_SIZE_MASK
;
238 static int is_writeble_pte(unsigned long pte
)
240 return pte
& PT_WRITABLE_MASK
;
243 static int is_dirty_gpte(unsigned long pte
)
245 return pte
& PT_DIRTY_MASK
;
248 static int is_rmap_spte(u64 pte
)
250 return is_shadow_present_pte(pte
);
253 static int is_last_spte(u64 pte
, int level
)
255 if (level
== PT_PAGE_TABLE_LEVEL
)
257 if (level
== PT_DIRECTORY_LEVEL
&& is_large_pte(pte
))
262 static pfn_t
spte_to_pfn(u64 pte
)
264 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
267 static gfn_t
pse36_gfn_delta(u32 gpte
)
269 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
271 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
274 static void __set_spte(u64
*sptep
, u64 spte
)
277 set_64bit((unsigned long *)sptep
, spte
);
279 set_64bit((unsigned long long *)sptep
, spte
);
283 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
284 struct kmem_cache
*base_cache
, int min
)
288 if (cache
->nobjs
>= min
)
290 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
291 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
294 cache
->objects
[cache
->nobjs
++] = obj
;
299 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
302 kfree(mc
->objects
[--mc
->nobjs
]);
305 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
310 if (cache
->nobjs
>= min
)
312 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
313 page
= alloc_page(GFP_KERNEL
);
316 set_page_private(page
, 0);
317 cache
->objects
[cache
->nobjs
++] = page_address(page
);
322 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
325 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
328 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
332 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
336 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
340 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
343 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
344 mmu_page_header_cache
, 4);
349 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
351 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
352 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
353 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
354 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
357 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
363 p
= mc
->objects
[--mc
->nobjs
];
367 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
369 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
370 sizeof(struct kvm_pte_chain
));
373 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
378 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
380 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
381 sizeof(struct kvm_rmap_desc
));
384 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
390 * Return the pointer to the largepage write count for a given
391 * gfn, handling slots that are not large page aligned.
393 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
397 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
398 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
399 return &slot
->lpage_info
[idx
].write_count
;
402 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
406 gfn
= unalias_gfn(kvm
, gfn
);
407 write_count
= slot_largepage_idx(gfn
,
408 gfn_to_memslot_unaliased(kvm
, gfn
));
412 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
416 gfn
= unalias_gfn(kvm
, gfn
);
417 write_count
= slot_largepage_idx(gfn
,
418 gfn_to_memslot_unaliased(kvm
, gfn
));
420 WARN_ON(*write_count
< 0);
423 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
425 struct kvm_memory_slot
*slot
;
428 gfn
= unalias_gfn(kvm
, gfn
);
429 slot
= gfn_to_memslot_unaliased(kvm
, gfn
);
431 largepage_idx
= slot_largepage_idx(gfn
, slot
);
432 return *largepage_idx
;
438 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
440 struct vm_area_struct
*vma
;
444 addr
= gfn_to_hva(kvm
, gfn
);
445 if (kvm_is_error_hva(addr
))
448 down_read(¤t
->mm
->mmap_sem
);
449 vma
= find_vma(current
->mm
, addr
);
450 if (vma
&& is_vm_hugetlb_page(vma
))
452 up_read(¤t
->mm
->mmap_sem
);
457 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
459 struct kvm_memory_slot
*slot
;
461 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
464 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
467 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
468 if (slot
&& slot
->dirty_bitmap
)
475 * Take gfn and return the reverse mapping to it.
476 * Note: gfn must be unaliased before this function get called
479 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
481 struct kvm_memory_slot
*slot
;
484 slot
= gfn_to_memslot(kvm
, gfn
);
486 return &slot
->rmap
[gfn
- slot
->base_gfn
];
488 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
489 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
491 return &slot
->lpage_info
[idx
].rmap_pde
;
495 * Reverse mapping data structures:
497 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
498 * that points to page_address(page).
500 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
501 * containing more mappings.
503 * Returns the number of rmap entries before the spte was added or zero if
504 * the spte was not added.
507 static int rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
509 struct kvm_mmu_page
*sp
;
510 struct kvm_rmap_desc
*desc
;
511 unsigned long *rmapp
;
514 if (!is_rmap_spte(*spte
))
516 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
517 sp
= page_header(__pa(spte
));
518 sp
->gfns
[spte
- sp
->spt
] = gfn
;
519 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
521 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
522 *rmapp
= (unsigned long)spte
;
523 } else if (!(*rmapp
& 1)) {
524 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
525 desc
= mmu_alloc_rmap_desc(vcpu
);
526 desc
->sptes
[0] = (u64
*)*rmapp
;
527 desc
->sptes
[1] = spte
;
528 *rmapp
= (unsigned long)desc
| 1;
530 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
531 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
532 while (desc
->sptes
[RMAP_EXT
-1] && desc
->more
) {
536 if (desc
->sptes
[RMAP_EXT
-1]) {
537 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
540 for (i
= 0; desc
->sptes
[i
]; ++i
)
542 desc
->sptes
[i
] = spte
;
547 static void rmap_desc_remove_entry(unsigned long *rmapp
,
548 struct kvm_rmap_desc
*desc
,
550 struct kvm_rmap_desc
*prev_desc
)
554 for (j
= RMAP_EXT
- 1; !desc
->sptes
[j
] && j
> i
; --j
)
556 desc
->sptes
[i
] = desc
->sptes
[j
];
557 desc
->sptes
[j
] = NULL
;
560 if (!prev_desc
&& !desc
->more
)
561 *rmapp
= (unsigned long)desc
->sptes
[0];
564 prev_desc
->more
= desc
->more
;
566 *rmapp
= (unsigned long)desc
->more
| 1;
567 mmu_free_rmap_desc(desc
);
570 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
572 struct kvm_rmap_desc
*desc
;
573 struct kvm_rmap_desc
*prev_desc
;
574 struct kvm_mmu_page
*sp
;
576 unsigned long *rmapp
;
579 if (!is_rmap_spte(*spte
))
581 sp
= page_header(__pa(spte
));
582 pfn
= spte_to_pfn(*spte
);
583 if (*spte
& shadow_accessed_mask
)
584 kvm_set_pfn_accessed(pfn
);
585 if (is_writeble_pte(*spte
))
586 kvm_release_pfn_dirty(pfn
);
588 kvm_release_pfn_clean(pfn
);
589 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
591 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
593 } else if (!(*rmapp
& 1)) {
594 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
595 if ((u64
*)*rmapp
!= spte
) {
596 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
602 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
603 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
606 for (i
= 0; i
< RMAP_EXT
&& desc
->sptes
[i
]; ++i
)
607 if (desc
->sptes
[i
] == spte
) {
608 rmap_desc_remove_entry(rmapp
,
620 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
622 struct kvm_rmap_desc
*desc
;
623 struct kvm_rmap_desc
*prev_desc
;
629 else if (!(*rmapp
& 1)) {
631 return (u64
*)*rmapp
;
634 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
638 for (i
= 0; i
< RMAP_EXT
&& desc
->sptes
[i
]; ++i
) {
639 if (prev_spte
== spte
)
640 return desc
->sptes
[i
];
641 prev_spte
= desc
->sptes
[i
];
648 static int rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
650 unsigned long *rmapp
;
652 int write_protected
= 0;
654 gfn
= unalias_gfn(kvm
, gfn
);
655 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
657 spte
= rmap_next(kvm
, rmapp
, NULL
);
660 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
661 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
662 if (is_writeble_pte(*spte
)) {
663 __set_spte(spte
, *spte
& ~PT_WRITABLE_MASK
);
666 spte
= rmap_next(kvm
, rmapp
, spte
);
668 if (write_protected
) {
671 spte
= rmap_next(kvm
, rmapp
, NULL
);
672 pfn
= spte_to_pfn(*spte
);
673 kvm_set_pfn_dirty(pfn
);
676 /* check for huge page mappings */
677 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
678 spte
= rmap_next(kvm
, rmapp
, NULL
);
681 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
682 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
683 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
684 if (is_writeble_pte(*spte
)) {
685 rmap_remove(kvm
, spte
);
687 __set_spte(spte
, shadow_trap_nonpresent_pte
);
691 spte
= rmap_next(kvm
, rmapp
, spte
);
694 return write_protected
;
697 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
700 int need_tlb_flush
= 0;
702 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
703 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
704 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
705 rmap_remove(kvm
, spte
);
706 __set_spte(spte
, shadow_trap_nonpresent_pte
);
709 return need_tlb_flush
;
712 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
713 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
))
719 * If mmap_sem isn't taken, we can look the memslots with only
720 * the mmu_lock by skipping over the slots with userspace_addr == 0.
722 for (i
= 0; i
< kvm
->nmemslots
; i
++) {
723 struct kvm_memory_slot
*memslot
= &kvm
->memslots
[i
];
724 unsigned long start
= memslot
->userspace_addr
;
727 /* mmu_lock protects userspace_addr */
731 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
732 if (hva
>= start
&& hva
< end
) {
733 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
734 retval
|= handler(kvm
, &memslot
->rmap
[gfn_offset
]);
735 retval
|= handler(kvm
,
736 &memslot
->lpage_info
[
738 KVM_PAGES_PER_HPAGE
].rmap_pde
);
745 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
747 return kvm_handle_hva(kvm
, hva
, kvm_unmap_rmapp
);
750 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
755 /* always return old for EPT */
756 if (!shadow_accessed_mask
)
759 spte
= rmap_next(kvm
, rmapp
, NULL
);
763 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
764 _young
= _spte
& PT_ACCESSED_MASK
;
767 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
769 spte
= rmap_next(kvm
, rmapp
, spte
);
774 #define RMAP_RECYCLE_THRESHOLD 1000
776 static void rmap_recycle(struct kvm_vcpu
*vcpu
, gfn_t gfn
, int lpage
)
778 unsigned long *rmapp
;
780 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
781 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
783 kvm_unmap_rmapp(vcpu
->kvm
, rmapp
);
784 kvm_flush_remote_tlbs(vcpu
->kvm
);
787 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
789 return kvm_handle_hva(kvm
, hva
, kvm_age_rmapp
);
793 static int is_empty_shadow_page(u64
*spt
)
798 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
799 if (is_shadow_present_pte(*pos
)) {
800 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
808 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
810 ASSERT(is_empty_shadow_page(sp
->spt
));
812 __free_page(virt_to_page(sp
->spt
));
813 __free_page(virt_to_page(sp
->gfns
));
815 ++kvm
->arch
.n_free_mmu_pages
;
818 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
820 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
823 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
826 struct kvm_mmu_page
*sp
;
828 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
829 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
830 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
831 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
832 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
833 INIT_LIST_HEAD(&sp
->oos_link
);
834 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
836 sp
->parent_pte
= parent_pte
;
837 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
841 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
842 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
844 struct kvm_pte_chain
*pte_chain
;
845 struct hlist_node
*node
;
850 if (!sp
->multimapped
) {
851 u64
*old
= sp
->parent_pte
;
854 sp
->parent_pte
= parent_pte
;
858 pte_chain
= mmu_alloc_pte_chain(vcpu
);
859 INIT_HLIST_HEAD(&sp
->parent_ptes
);
860 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
861 pte_chain
->parent_ptes
[0] = old
;
863 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
864 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
866 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
867 if (!pte_chain
->parent_ptes
[i
]) {
868 pte_chain
->parent_ptes
[i
] = parent_pte
;
872 pte_chain
= mmu_alloc_pte_chain(vcpu
);
874 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
875 pte_chain
->parent_ptes
[0] = parent_pte
;
878 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
881 struct kvm_pte_chain
*pte_chain
;
882 struct hlist_node
*node
;
885 if (!sp
->multimapped
) {
886 BUG_ON(sp
->parent_pte
!= parent_pte
);
887 sp
->parent_pte
= NULL
;
890 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
891 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
892 if (!pte_chain
->parent_ptes
[i
])
894 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
896 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
897 && pte_chain
->parent_ptes
[i
+ 1]) {
898 pte_chain
->parent_ptes
[i
]
899 = pte_chain
->parent_ptes
[i
+ 1];
902 pte_chain
->parent_ptes
[i
] = NULL
;
904 hlist_del(&pte_chain
->link
);
905 mmu_free_pte_chain(pte_chain
);
906 if (hlist_empty(&sp
->parent_ptes
)) {
908 sp
->parent_pte
= NULL
;
917 static void mmu_parent_walk(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
918 mmu_parent_walk_fn fn
)
920 struct kvm_pte_chain
*pte_chain
;
921 struct hlist_node
*node
;
922 struct kvm_mmu_page
*parent_sp
;
925 if (!sp
->multimapped
&& sp
->parent_pte
) {
926 parent_sp
= page_header(__pa(sp
->parent_pte
));
928 mmu_parent_walk(vcpu
, parent_sp
, fn
);
931 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
932 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
933 if (!pte_chain
->parent_ptes
[i
])
935 parent_sp
= page_header(__pa(pte_chain
->parent_ptes
[i
]));
937 mmu_parent_walk(vcpu
, parent_sp
, fn
);
941 static void kvm_mmu_update_unsync_bitmap(u64
*spte
)
944 struct kvm_mmu_page
*sp
= page_header(__pa(spte
));
946 index
= spte
- sp
->spt
;
947 if (!__test_and_set_bit(index
, sp
->unsync_child_bitmap
))
948 sp
->unsync_children
++;
949 WARN_ON(!sp
->unsync_children
);
952 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page
*sp
)
954 struct kvm_pte_chain
*pte_chain
;
955 struct hlist_node
*node
;
961 if (!sp
->multimapped
) {
962 kvm_mmu_update_unsync_bitmap(sp
->parent_pte
);
966 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
967 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
968 if (!pte_chain
->parent_ptes
[i
])
970 kvm_mmu_update_unsync_bitmap(pte_chain
->parent_ptes
[i
]);
974 static int unsync_walk_fn(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
976 kvm_mmu_update_parents_unsync(sp
);
980 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu
*vcpu
,
981 struct kvm_mmu_page
*sp
)
983 mmu_parent_walk(vcpu
, sp
, unsync_walk_fn
);
984 kvm_mmu_update_parents_unsync(sp
);
987 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
988 struct kvm_mmu_page
*sp
)
992 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
993 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
996 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
997 struct kvm_mmu_page
*sp
)
1002 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
1006 #define KVM_PAGE_ARRAY_NR 16
1008 struct kvm_mmu_pages
{
1009 struct mmu_page_and_offset
{
1010 struct kvm_mmu_page
*sp
;
1012 } page
[KVM_PAGE_ARRAY_NR
];
1016 #define for_each_unsync_children(bitmap, idx) \
1017 for (idx = find_first_bit(bitmap, 512); \
1019 idx = find_next_bit(bitmap, 512, idx+1))
1021 static int mmu_pages_add(struct kvm_mmu_pages
*pvec
, struct kvm_mmu_page
*sp
,
1027 for (i
=0; i
< pvec
->nr
; i
++)
1028 if (pvec
->page
[i
].sp
== sp
)
1031 pvec
->page
[pvec
->nr
].sp
= sp
;
1032 pvec
->page
[pvec
->nr
].idx
= idx
;
1034 return (pvec
->nr
== KVM_PAGE_ARRAY_NR
);
1037 static int __mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1038 struct kvm_mmu_pages
*pvec
)
1040 int i
, ret
, nr_unsync_leaf
= 0;
1042 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
1043 u64 ent
= sp
->spt
[i
];
1045 if (is_shadow_present_pte(ent
) && !is_large_pte(ent
)) {
1046 struct kvm_mmu_page
*child
;
1047 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
1049 if (child
->unsync_children
) {
1050 if (mmu_pages_add(pvec
, child
, i
))
1053 ret
= __mmu_unsync_walk(child
, pvec
);
1055 __clear_bit(i
, sp
->unsync_child_bitmap
);
1057 nr_unsync_leaf
+= ret
;
1062 if (child
->unsync
) {
1064 if (mmu_pages_add(pvec
, child
, i
))
1070 if (find_first_bit(sp
->unsync_child_bitmap
, 512) == 512)
1071 sp
->unsync_children
= 0;
1073 return nr_unsync_leaf
;
1076 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1077 struct kvm_mmu_pages
*pvec
)
1079 if (!sp
->unsync_children
)
1082 mmu_pages_add(pvec
, sp
, 0);
1083 return __mmu_unsync_walk(sp
, pvec
);
1086 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
1089 struct hlist_head
*bucket
;
1090 struct kvm_mmu_page
*sp
;
1091 struct hlist_node
*node
;
1093 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1094 index
= kvm_page_table_hashfn(gfn
);
1095 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1096 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
1097 if (sp
->gfn
== gfn
&& !sp
->role
.direct
1098 && !sp
->role
.invalid
) {
1099 pgprintk("%s: found role %x\n",
1100 __func__
, sp
->role
.word
);
1106 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1108 WARN_ON(!sp
->unsync
);
1110 --kvm
->stat
.mmu_unsync
;
1113 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
);
1115 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1117 if (sp
->role
.glevels
!= vcpu
->arch
.mmu
.root_level
) {
1118 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1122 if (rmap_write_protect(vcpu
->kvm
, sp
->gfn
))
1123 kvm_flush_remote_tlbs(vcpu
->kvm
);
1124 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1125 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1126 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1130 kvm_mmu_flush_tlb(vcpu
);
1134 struct mmu_page_path
{
1135 struct kvm_mmu_page
*parent
[PT64_ROOT_LEVEL
-1];
1136 unsigned int idx
[PT64_ROOT_LEVEL
-1];
1139 #define for_each_sp(pvec, sp, parents, i) \
1140 for (i = mmu_pages_next(&pvec, &parents, -1), \
1141 sp = pvec.page[i].sp; \
1142 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1143 i = mmu_pages_next(&pvec, &parents, i))
1145 static int mmu_pages_next(struct kvm_mmu_pages
*pvec
,
1146 struct mmu_page_path
*parents
,
1151 for (n
= i
+1; n
< pvec
->nr
; n
++) {
1152 struct kvm_mmu_page
*sp
= pvec
->page
[n
].sp
;
1154 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1155 parents
->idx
[0] = pvec
->page
[n
].idx
;
1159 parents
->parent
[sp
->role
.level
-2] = sp
;
1160 parents
->idx
[sp
->role
.level
-1] = pvec
->page
[n
].idx
;
1166 static void mmu_pages_clear_parents(struct mmu_page_path
*parents
)
1168 struct kvm_mmu_page
*sp
;
1169 unsigned int level
= 0;
1172 unsigned int idx
= parents
->idx
[level
];
1174 sp
= parents
->parent
[level
];
1178 --sp
->unsync_children
;
1179 WARN_ON((int)sp
->unsync_children
< 0);
1180 __clear_bit(idx
, sp
->unsync_child_bitmap
);
1182 } while (level
< PT64_ROOT_LEVEL
-1 && !sp
->unsync_children
);
1185 static void kvm_mmu_pages_init(struct kvm_mmu_page
*parent
,
1186 struct mmu_page_path
*parents
,
1187 struct kvm_mmu_pages
*pvec
)
1189 parents
->parent
[parent
->role
.level
-1] = NULL
;
1193 static void mmu_sync_children(struct kvm_vcpu
*vcpu
,
1194 struct kvm_mmu_page
*parent
)
1197 struct kvm_mmu_page
*sp
;
1198 struct mmu_page_path parents
;
1199 struct kvm_mmu_pages pages
;
1201 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1202 while (mmu_unsync_walk(parent
, &pages
)) {
1205 for_each_sp(pages
, sp
, parents
, i
)
1206 protected |= rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1209 kvm_flush_remote_tlbs(vcpu
->kvm
);
1211 for_each_sp(pages
, sp
, parents
, i
) {
1212 kvm_sync_page(vcpu
, sp
);
1213 mmu_pages_clear_parents(&parents
);
1215 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1216 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1220 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1228 union kvm_mmu_page_role role
;
1231 struct hlist_head
*bucket
;
1232 struct kvm_mmu_page
*sp
;
1233 struct hlist_node
*node
, *tmp
;
1235 role
= vcpu
->arch
.mmu
.base_role
;
1237 role
.direct
= direct
;
1238 role
.access
= access
;
1239 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1240 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1241 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1242 role
.quadrant
= quadrant
;
1244 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
1246 index
= kvm_page_table_hashfn(gfn
);
1247 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1248 hlist_for_each_entry_safe(sp
, node
, tmp
, bucket
, hash_link
)
1249 if (sp
->gfn
== gfn
) {
1251 if (kvm_sync_page(vcpu
, sp
))
1254 if (sp
->role
.word
!= role
.word
)
1257 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1258 if (sp
->unsync_children
) {
1259 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
1260 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1262 pgprintk("%s: found\n", __func__
);
1265 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1266 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
1269 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
1272 hlist_add_head(&sp
->hash_link
, bucket
);
1274 if (rmap_write_protect(vcpu
->kvm
, gfn
))
1275 kvm_flush_remote_tlbs(vcpu
->kvm
);
1276 account_shadowed(vcpu
->kvm
, gfn
);
1278 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1279 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1281 nonpaging_prefetch_page(vcpu
, sp
);
1285 static void shadow_walk_init(struct kvm_shadow_walk_iterator
*iterator
,
1286 struct kvm_vcpu
*vcpu
, u64 addr
)
1288 iterator
->addr
= addr
;
1289 iterator
->shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1290 iterator
->level
= vcpu
->arch
.mmu
.shadow_root_level
;
1291 if (iterator
->level
== PT32E_ROOT_LEVEL
) {
1292 iterator
->shadow_addr
1293 = vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1294 iterator
->shadow_addr
&= PT64_BASE_ADDR_MASK
;
1296 if (!iterator
->shadow_addr
)
1297 iterator
->level
= 0;
1301 static bool shadow_walk_okay(struct kvm_shadow_walk_iterator
*iterator
)
1303 if (iterator
->level
< PT_PAGE_TABLE_LEVEL
)
1305 iterator
->index
= SHADOW_PT_INDEX(iterator
->addr
, iterator
->level
);
1306 iterator
->sptep
= ((u64
*)__va(iterator
->shadow_addr
)) + iterator
->index
;
1310 static void shadow_walk_next(struct kvm_shadow_walk_iterator
*iterator
)
1312 iterator
->shadow_addr
= *iterator
->sptep
& PT64_BASE_ADDR_MASK
;
1316 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1317 struct kvm_mmu_page
*sp
)
1325 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1328 if (is_shadow_present_pte(ent
)) {
1329 if (!is_last_spte(ent
, sp
->role
.level
)) {
1330 ent
&= PT64_BASE_ADDR_MASK
;
1331 mmu_page_remove_parent_pte(page_header(ent
),
1334 if (is_large_pte(ent
))
1336 rmap_remove(kvm
, &pt
[i
]);
1339 pt
[i
] = shadow_trap_nonpresent_pte
;
1343 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1345 mmu_page_remove_parent_pte(sp
, parent_pte
);
1348 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1351 struct kvm_vcpu
*vcpu
;
1353 kvm_for_each_vcpu(i
, vcpu
, kvm
)
1354 vcpu
->arch
.last_pte_updated
= NULL
;
1357 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1361 while (sp
->multimapped
|| sp
->parent_pte
) {
1362 if (!sp
->multimapped
)
1363 parent_pte
= sp
->parent_pte
;
1365 struct kvm_pte_chain
*chain
;
1367 chain
= container_of(sp
->parent_ptes
.first
,
1368 struct kvm_pte_chain
, link
);
1369 parent_pte
= chain
->parent_ptes
[0];
1371 BUG_ON(!parent_pte
);
1372 kvm_mmu_put_page(sp
, parent_pte
);
1373 __set_spte(parent_pte
, shadow_trap_nonpresent_pte
);
1377 static int mmu_zap_unsync_children(struct kvm
*kvm
,
1378 struct kvm_mmu_page
*parent
)
1381 struct mmu_page_path parents
;
1382 struct kvm_mmu_pages pages
;
1384 if (parent
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1387 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1388 while (mmu_unsync_walk(parent
, &pages
)) {
1389 struct kvm_mmu_page
*sp
;
1391 for_each_sp(pages
, sp
, parents
, i
) {
1392 kvm_mmu_zap_page(kvm
, sp
);
1393 mmu_pages_clear_parents(&parents
);
1396 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1402 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1405 ++kvm
->stat
.mmu_shadow_zapped
;
1406 ret
= mmu_zap_unsync_children(kvm
, sp
);
1407 kvm_mmu_page_unlink_children(kvm
, sp
);
1408 kvm_mmu_unlink_parents(kvm
, sp
);
1409 kvm_flush_remote_tlbs(kvm
);
1410 if (!sp
->role
.invalid
&& !sp
->role
.direct
)
1411 unaccount_shadowed(kvm
, sp
->gfn
);
1413 kvm_unlink_unsync_page(kvm
, sp
);
1414 if (!sp
->root_count
) {
1415 hlist_del(&sp
->hash_link
);
1416 kvm_mmu_free_page(kvm
, sp
);
1418 sp
->role
.invalid
= 1;
1419 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1420 kvm_reload_remote_mmus(kvm
);
1422 kvm_mmu_reset_last_pte_updated(kvm
);
1427 * Changing the number of mmu pages allocated to the vm
1428 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1430 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
1434 used_pages
= kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
;
1435 used_pages
= max(0, used_pages
);
1438 * If we set the number of mmu pages to be smaller be than the
1439 * number of actived pages , we must to free some mmu pages before we
1443 if (used_pages
> kvm_nr_mmu_pages
) {
1444 while (used_pages
> kvm_nr_mmu_pages
) {
1445 struct kvm_mmu_page
*page
;
1447 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1448 struct kvm_mmu_page
, link
);
1449 kvm_mmu_zap_page(kvm
, page
);
1452 kvm
->arch
.n_free_mmu_pages
= 0;
1455 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
1456 - kvm
->arch
.n_alloc_mmu_pages
;
1458 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
1461 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1464 struct hlist_head
*bucket
;
1465 struct kvm_mmu_page
*sp
;
1466 struct hlist_node
*node
, *n
;
1469 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1471 index
= kvm_page_table_hashfn(gfn
);
1472 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1473 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
1474 if (sp
->gfn
== gfn
&& !sp
->role
.direct
) {
1475 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
1478 if (kvm_mmu_zap_page(kvm
, sp
))
1484 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1487 struct hlist_head
*bucket
;
1488 struct kvm_mmu_page
*sp
;
1489 struct hlist_node
*node
, *nn
;
1491 index
= kvm_page_table_hashfn(gfn
);
1492 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1493 hlist_for_each_entry_safe(sp
, node
, nn
, bucket
, hash_link
) {
1494 if (sp
->gfn
== gfn
&& !sp
->role
.direct
1495 && !sp
->role
.invalid
) {
1496 pgprintk("%s: zap %lx %x\n",
1497 __func__
, gfn
, sp
->role
.word
);
1498 kvm_mmu_zap_page(kvm
, sp
);
1503 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1505 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1506 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1508 __set_bit(slot
, sp
->slot_bitmap
);
1511 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1516 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1519 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1520 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1521 __set_spte(&pt
[i
], shadow_trap_nonpresent_pte
);
1525 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1529 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1531 if (gpa
== UNMAPPED_GVA
)
1534 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1540 * The function is based on mtrr_type_lookup() in
1541 * arch/x86/kernel/cpu/mtrr/generic.c
1543 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1548 u8 prev_match
, curr_match
;
1549 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1551 if (!mtrr_state
->enabled
)
1554 /* Make end inclusive end, instead of exclusive */
1557 /* Look in fixed ranges. Just return the type as per start */
1558 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1561 if (start
< 0x80000) {
1563 idx
+= (start
>> 16);
1564 return mtrr_state
->fixed_ranges
[idx
];
1565 } else if (start
< 0xC0000) {
1567 idx
+= ((start
- 0x80000) >> 14);
1568 return mtrr_state
->fixed_ranges
[idx
];
1569 } else if (start
< 0x1000000) {
1571 idx
+= ((start
- 0xC0000) >> 12);
1572 return mtrr_state
->fixed_ranges
[idx
];
1577 * Look in variable ranges
1578 * Look of multiple ranges matching this address and pick type
1579 * as per MTRR precedence
1581 if (!(mtrr_state
->enabled
& 2))
1582 return mtrr_state
->def_type
;
1585 for (i
= 0; i
< num_var_ranges
; ++i
) {
1586 unsigned short start_state
, end_state
;
1588 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1591 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1592 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1593 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1594 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1596 start_state
= ((start
& mask
) == (base
& mask
));
1597 end_state
= ((end
& mask
) == (base
& mask
));
1598 if (start_state
!= end_state
)
1601 if ((start
& mask
) != (base
& mask
))
1604 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1605 if (prev_match
== 0xFF) {
1606 prev_match
= curr_match
;
1610 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1611 curr_match
== MTRR_TYPE_UNCACHABLE
)
1612 return MTRR_TYPE_UNCACHABLE
;
1614 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1615 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1616 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1617 curr_match
== MTRR_TYPE_WRBACK
)) {
1618 prev_match
= MTRR_TYPE_WRTHROUGH
;
1619 curr_match
= MTRR_TYPE_WRTHROUGH
;
1622 if (prev_match
!= curr_match
)
1623 return MTRR_TYPE_UNCACHABLE
;
1626 if (prev_match
!= 0xFF)
1629 return mtrr_state
->def_type
;
1632 u8
kvm_get_guest_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1636 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1637 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1638 if (mtrr
== 0xfe || mtrr
== 0xff)
1639 mtrr
= MTRR_TYPE_WRBACK
;
1642 EXPORT_SYMBOL_GPL(kvm_get_guest_memory_type
);
1644 static int kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1647 struct hlist_head
*bucket
;
1648 struct kvm_mmu_page
*s
;
1649 struct hlist_node
*node
, *n
;
1651 index
= kvm_page_table_hashfn(sp
->gfn
);
1652 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1653 /* don't unsync if pagetable is shadowed with multiple roles */
1654 hlist_for_each_entry_safe(s
, node
, n
, bucket
, hash_link
) {
1655 if (s
->gfn
!= sp
->gfn
|| s
->role
.direct
)
1657 if (s
->role
.word
!= sp
->role
.word
)
1660 ++vcpu
->kvm
->stat
.mmu_unsync
;
1663 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1665 mmu_convert_notrap(sp
);
1669 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1672 struct kvm_mmu_page
*shadow
;
1674 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1676 if (shadow
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1680 if (can_unsync
&& oos_shadow
)
1681 return kvm_unsync_page(vcpu
, shadow
);
1687 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
,
1688 unsigned pte_access
, int user_fault
,
1689 int write_fault
, int dirty
, int largepage
,
1690 gfn_t gfn
, pfn_t pfn
, bool speculative
,
1697 * We don't set the accessed bit, since we sometimes want to see
1698 * whether the guest actually used the pte (in order to detect
1701 spte
= shadow_base_present_pte
| shadow_dirty_mask
;
1703 spte
|= shadow_accessed_mask
;
1705 pte_access
&= ~ACC_WRITE_MASK
;
1706 if (pte_access
& ACC_EXEC_MASK
)
1707 spte
|= shadow_x_mask
;
1709 spte
|= shadow_nx_mask
;
1710 if (pte_access
& ACC_USER_MASK
)
1711 spte
|= shadow_user_mask
;
1713 spte
|= PT_PAGE_SIZE_MASK
;
1715 spte
|= kvm_x86_ops
->get_mt_mask(vcpu
, gfn
,
1716 kvm_is_mmio_pfn(pfn
));
1718 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1720 if ((pte_access
& ACC_WRITE_MASK
)
1721 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1723 if (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
)) {
1725 spte
= shadow_trap_nonpresent_pte
;
1729 spte
|= PT_WRITABLE_MASK
;
1732 * Optimization: for pte sync, if spte was writable the hash
1733 * lookup is unnecessary (and expensive). Write protection
1734 * is responsibility of mmu_get_page / kvm_sync_page.
1735 * Same reasoning can be applied to dirty page accounting.
1737 if (!can_unsync
&& is_writeble_pte(*sptep
))
1740 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1741 pgprintk("%s: found shadow page for %lx, marking ro\n",
1744 pte_access
&= ~ACC_WRITE_MASK
;
1745 if (is_writeble_pte(spte
))
1746 spte
&= ~PT_WRITABLE_MASK
;
1750 if (pte_access
& ACC_WRITE_MASK
)
1751 mark_page_dirty(vcpu
->kvm
, gfn
);
1754 __set_spte(sptep
, spte
);
1758 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
,
1759 unsigned pt_access
, unsigned pte_access
,
1760 int user_fault
, int write_fault
, int dirty
,
1761 int *ptwrite
, int largepage
, gfn_t gfn
,
1762 pfn_t pfn
, bool speculative
)
1764 int was_rmapped
= 0;
1765 int was_writeble
= is_writeble_pte(*sptep
);
1768 pgprintk("%s: spte %llx access %x write_fault %d"
1769 " user_fault %d gfn %lx\n",
1770 __func__
, *sptep
, pt_access
,
1771 write_fault
, user_fault
, gfn
);
1773 if (is_rmap_spte(*sptep
)) {
1775 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1776 * the parent of the now unreachable PTE.
1778 if (largepage
&& !is_large_pte(*sptep
)) {
1779 struct kvm_mmu_page
*child
;
1782 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1783 mmu_page_remove_parent_pte(child
, sptep
);
1784 } else if (pfn
!= spte_to_pfn(*sptep
)) {
1785 pgprintk("hfn old %lx new %lx\n",
1786 spte_to_pfn(*sptep
), pfn
);
1787 rmap_remove(vcpu
->kvm
, sptep
);
1791 if (set_spte(vcpu
, sptep
, pte_access
, user_fault
, write_fault
,
1792 dirty
, largepage
, gfn
, pfn
, speculative
, true)) {
1795 kvm_x86_ops
->tlb_flush(vcpu
);
1798 pgprintk("%s: setting spte %llx\n", __func__
, *sptep
);
1799 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1800 is_large_pte(*sptep
)? "2MB" : "4kB",
1801 is_present_pte(*sptep
)?"RW":"R", gfn
,
1802 *shadow_pte
, sptep
);
1803 if (!was_rmapped
&& is_large_pte(*sptep
))
1804 ++vcpu
->kvm
->stat
.lpages
;
1806 page_header_update_slot(vcpu
->kvm
, sptep
, gfn
);
1808 rmap_count
= rmap_add(vcpu
, sptep
, gfn
, largepage
);
1809 if (!is_rmap_spte(*sptep
))
1810 kvm_release_pfn_clean(pfn
);
1811 if (rmap_count
> RMAP_RECYCLE_THRESHOLD
)
1812 rmap_recycle(vcpu
, gfn
, largepage
);
1815 kvm_release_pfn_dirty(pfn
);
1817 kvm_release_pfn_clean(pfn
);
1820 vcpu
->arch
.last_pte_updated
= sptep
;
1821 vcpu
->arch
.last_pte_gfn
= gfn
;
1825 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1829 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1830 int largepage
, gfn_t gfn
, pfn_t pfn
)
1832 struct kvm_shadow_walk_iterator iterator
;
1833 struct kvm_mmu_page
*sp
;
1837 for_each_shadow_entry(vcpu
, (u64
)gfn
<< PAGE_SHIFT
, iterator
) {
1838 if (iterator
.level
== PT_PAGE_TABLE_LEVEL
1839 || (largepage
&& iterator
.level
== PT_DIRECTORY_LEVEL
)) {
1840 mmu_set_spte(vcpu
, iterator
.sptep
, ACC_ALL
, ACC_ALL
,
1841 0, write
, 1, &pt_write
,
1842 largepage
, gfn
, pfn
, false);
1843 ++vcpu
->stat
.pf_fixed
;
1847 if (*iterator
.sptep
== shadow_trap_nonpresent_pte
) {
1848 pseudo_gfn
= (iterator
.addr
& PT64_DIR_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1849 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, iterator
.addr
,
1851 1, ACC_ALL
, iterator
.sptep
);
1853 pgprintk("nonpaging_map: ENOMEM\n");
1854 kvm_release_pfn_clean(pfn
);
1858 __set_spte(iterator
.sptep
,
1860 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1861 | shadow_user_mask
| shadow_x_mask
);
1867 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1872 unsigned long mmu_seq
;
1874 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1875 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1879 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1881 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1884 if (is_error_pfn(pfn
)) {
1885 kvm_release_pfn_clean(pfn
);
1889 spin_lock(&vcpu
->kvm
->mmu_lock
);
1890 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1892 kvm_mmu_free_some_pages(vcpu
);
1893 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
);
1894 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1900 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1901 kvm_release_pfn_clean(pfn
);
1906 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1909 struct kvm_mmu_page
*sp
;
1911 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1913 spin_lock(&vcpu
->kvm
->mmu_lock
);
1914 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1915 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1917 sp
= page_header(root
);
1919 if (!sp
->root_count
&& sp
->role
.invalid
)
1920 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1921 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1922 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1925 for (i
= 0; i
< 4; ++i
) {
1926 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1929 root
&= PT64_BASE_ADDR_MASK
;
1930 sp
= page_header(root
);
1932 if (!sp
->root_count
&& sp
->role
.invalid
)
1933 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1935 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1937 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1938 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1941 static int mmu_check_root(struct kvm_vcpu
*vcpu
, gfn_t root_gfn
)
1945 if (!kvm_is_visible_gfn(vcpu
->kvm
, root_gfn
)) {
1946 set_bit(KVM_REQ_TRIPLE_FAULT
, &vcpu
->requests
);
1953 static int mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1957 struct kvm_mmu_page
*sp
;
1961 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1963 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1964 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1966 ASSERT(!VALID_PAGE(root
));
1969 if (mmu_check_root(vcpu
, root_gfn
))
1971 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1972 PT64_ROOT_LEVEL
, direct
,
1974 root
= __pa(sp
->spt
);
1976 vcpu
->arch
.mmu
.root_hpa
= root
;
1979 direct
= !is_paging(vcpu
);
1982 for (i
= 0; i
< 4; ++i
) {
1983 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1985 ASSERT(!VALID_PAGE(root
));
1986 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1987 pdptr
= kvm_pdptr_read(vcpu
, i
);
1988 if (!is_present_gpte(pdptr
)) {
1989 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1992 root_gfn
= pdptr
>> PAGE_SHIFT
;
1993 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1995 if (mmu_check_root(vcpu
, root_gfn
))
1997 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1998 PT32_ROOT_LEVEL
, direct
,
2000 root
= __pa(sp
->spt
);
2002 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
2004 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
2008 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2011 struct kvm_mmu_page
*sp
;
2013 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2015 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2016 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2017 sp
= page_header(root
);
2018 mmu_sync_children(vcpu
, sp
);
2021 for (i
= 0; i
< 4; ++i
) {
2022 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2024 if (root
&& VALID_PAGE(root
)) {
2025 root
&= PT64_BASE_ADDR_MASK
;
2026 sp
= page_header(root
);
2027 mmu_sync_children(vcpu
, sp
);
2032 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2034 spin_lock(&vcpu
->kvm
->mmu_lock
);
2035 mmu_sync_roots(vcpu
);
2036 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2039 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
2044 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
2050 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
2051 r
= mmu_topup_memory_caches(vcpu
);
2056 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2058 gfn
= gva
>> PAGE_SHIFT
;
2060 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
2061 error_code
& PFERR_WRITE_MASK
, gfn
);
2064 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
2070 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2071 unsigned long mmu_seq
;
2074 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2076 r
= mmu_topup_memory_caches(vcpu
);
2080 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
2081 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2084 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2086 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2087 if (is_error_pfn(pfn
)) {
2088 kvm_release_pfn_clean(pfn
);
2091 spin_lock(&vcpu
->kvm
->mmu_lock
);
2092 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2094 kvm_mmu_free_some_pages(vcpu
);
2095 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
2096 largepage
, gfn
, pfn
);
2097 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2102 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2103 kvm_release_pfn_clean(pfn
);
2107 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
2109 mmu_free_roots(vcpu
);
2112 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
2114 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2116 context
->new_cr3
= nonpaging_new_cr3
;
2117 context
->page_fault
= nonpaging_page_fault
;
2118 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2119 context
->free
= nonpaging_free
;
2120 context
->prefetch_page
= nonpaging_prefetch_page
;
2121 context
->sync_page
= nonpaging_sync_page
;
2122 context
->invlpg
= nonpaging_invlpg
;
2123 context
->root_level
= 0;
2124 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2125 context
->root_hpa
= INVALID_PAGE
;
2129 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2131 ++vcpu
->stat
.tlb_flush
;
2132 kvm_x86_ops
->tlb_flush(vcpu
);
2135 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2137 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
2138 mmu_free_roots(vcpu
);
2141 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2145 kvm_inject_page_fault(vcpu
, addr
, err_code
);
2148 static void paging_free(struct kvm_vcpu
*vcpu
)
2150 nonpaging_free(vcpu
);
2153 static bool is_rsvd_bits_set(struct kvm_vcpu
*vcpu
, u64 gpte
, int level
)
2157 bit7
= (gpte
>> 7) & 1;
2158 return (gpte
& vcpu
->arch
.mmu
.rsvd_bits_mask
[bit7
][level
-1]) != 0;
2162 #include "paging_tmpl.h"
2166 #include "paging_tmpl.h"
2169 static void reset_rsvds_bits_mask(struct kvm_vcpu
*vcpu
, int level
)
2171 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2172 int maxphyaddr
= cpuid_maxphyaddr(vcpu
);
2173 u64 exb_bit_rsvd
= 0;
2176 exb_bit_rsvd
= rsvd_bits(63, 63);
2178 case PT32_ROOT_LEVEL
:
2179 /* no rsvd bits for 2 level 4K page table entries */
2180 context
->rsvd_bits_mask
[0][1] = 0;
2181 context
->rsvd_bits_mask
[0][0] = 0;
2182 if (is_cpuid_PSE36())
2183 /* 36bits PSE 4MB page */
2184 context
->rsvd_bits_mask
[1][1] = rsvd_bits(17, 21);
2186 /* 32 bits PSE 4MB page */
2187 context
->rsvd_bits_mask
[1][1] = rsvd_bits(13, 21);
2188 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[1][0];
2190 case PT32E_ROOT_LEVEL
:
2191 context
->rsvd_bits_mask
[0][2] =
2192 rsvd_bits(maxphyaddr
, 63) |
2193 rsvd_bits(7, 8) | rsvd_bits(1, 2); /* PDPTE */
2194 context
->rsvd_bits_mask
[0][1] = exb_bit_rsvd
|
2195 rsvd_bits(maxphyaddr
, 62); /* PDE */
2196 context
->rsvd_bits_mask
[0][0] = exb_bit_rsvd
|
2197 rsvd_bits(maxphyaddr
, 62); /* PTE */
2198 context
->rsvd_bits_mask
[1][1] = exb_bit_rsvd
|
2199 rsvd_bits(maxphyaddr
, 62) |
2200 rsvd_bits(13, 20); /* large page */
2201 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[1][0];
2203 case PT64_ROOT_LEVEL
:
2204 context
->rsvd_bits_mask
[0][3] = exb_bit_rsvd
|
2205 rsvd_bits(maxphyaddr
, 51) | rsvd_bits(7, 8);
2206 context
->rsvd_bits_mask
[0][2] = exb_bit_rsvd
|
2207 rsvd_bits(maxphyaddr
, 51) | rsvd_bits(7, 8);
2208 context
->rsvd_bits_mask
[0][1] = exb_bit_rsvd
|
2209 rsvd_bits(maxphyaddr
, 51);
2210 context
->rsvd_bits_mask
[0][0] = exb_bit_rsvd
|
2211 rsvd_bits(maxphyaddr
, 51);
2212 context
->rsvd_bits_mask
[1][3] = context
->rsvd_bits_mask
[0][3];
2213 context
->rsvd_bits_mask
[1][2] = context
->rsvd_bits_mask
[0][2];
2214 context
->rsvd_bits_mask
[1][1] = exb_bit_rsvd
|
2215 rsvd_bits(maxphyaddr
, 51) |
2216 rsvd_bits(13, 20); /* large page */
2217 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[1][0];
2222 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
2224 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2226 ASSERT(is_pae(vcpu
));
2227 context
->new_cr3
= paging_new_cr3
;
2228 context
->page_fault
= paging64_page_fault
;
2229 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2230 context
->prefetch_page
= paging64_prefetch_page
;
2231 context
->sync_page
= paging64_sync_page
;
2232 context
->invlpg
= paging64_invlpg
;
2233 context
->free
= paging_free
;
2234 context
->root_level
= level
;
2235 context
->shadow_root_level
= level
;
2236 context
->root_hpa
= INVALID_PAGE
;
2240 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
2242 reset_rsvds_bits_mask(vcpu
, PT64_ROOT_LEVEL
);
2243 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
2246 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
2248 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2250 reset_rsvds_bits_mask(vcpu
, PT32_ROOT_LEVEL
);
2251 context
->new_cr3
= paging_new_cr3
;
2252 context
->page_fault
= paging32_page_fault
;
2253 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2254 context
->free
= paging_free
;
2255 context
->prefetch_page
= paging32_prefetch_page
;
2256 context
->sync_page
= paging32_sync_page
;
2257 context
->invlpg
= paging32_invlpg
;
2258 context
->root_level
= PT32_ROOT_LEVEL
;
2259 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2260 context
->root_hpa
= INVALID_PAGE
;
2264 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
2266 reset_rsvds_bits_mask(vcpu
, PT32E_ROOT_LEVEL
);
2267 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
2270 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2272 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2274 context
->new_cr3
= nonpaging_new_cr3
;
2275 context
->page_fault
= tdp_page_fault
;
2276 context
->free
= nonpaging_free
;
2277 context
->prefetch_page
= nonpaging_prefetch_page
;
2278 context
->sync_page
= nonpaging_sync_page
;
2279 context
->invlpg
= nonpaging_invlpg
;
2280 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2281 context
->root_hpa
= INVALID_PAGE
;
2283 if (!is_paging(vcpu
)) {
2284 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2285 context
->root_level
= 0;
2286 } else if (is_long_mode(vcpu
)) {
2287 reset_rsvds_bits_mask(vcpu
, PT64_ROOT_LEVEL
);
2288 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2289 context
->root_level
= PT64_ROOT_LEVEL
;
2290 } else if (is_pae(vcpu
)) {
2291 reset_rsvds_bits_mask(vcpu
, PT32E_ROOT_LEVEL
);
2292 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2293 context
->root_level
= PT32E_ROOT_LEVEL
;
2295 reset_rsvds_bits_mask(vcpu
, PT32_ROOT_LEVEL
);
2296 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2297 context
->root_level
= PT32_ROOT_LEVEL
;
2303 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2308 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2310 if (!is_paging(vcpu
))
2311 r
= nonpaging_init_context(vcpu
);
2312 else if (is_long_mode(vcpu
))
2313 r
= paging64_init_context(vcpu
);
2314 else if (is_pae(vcpu
))
2315 r
= paging32E_init_context(vcpu
);
2317 r
= paging32_init_context(vcpu
);
2319 vcpu
->arch
.mmu
.base_role
.glevels
= vcpu
->arch
.mmu
.root_level
;
2324 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
2326 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2329 return init_kvm_tdp_mmu(vcpu
);
2331 return init_kvm_softmmu(vcpu
);
2334 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
2337 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
2338 vcpu
->arch
.mmu
.free(vcpu
);
2339 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2343 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
2345 destroy_kvm_mmu(vcpu
);
2346 return init_kvm_mmu(vcpu
);
2348 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
2350 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
2354 r
= mmu_topup_memory_caches(vcpu
);
2357 spin_lock(&vcpu
->kvm
->mmu_lock
);
2358 kvm_mmu_free_some_pages(vcpu
);
2359 r
= mmu_alloc_roots(vcpu
);
2360 mmu_sync_roots(vcpu
);
2361 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2364 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
2365 kvm_mmu_flush_tlb(vcpu
);
2369 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
2371 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
2373 mmu_free_roots(vcpu
);
2376 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
2377 struct kvm_mmu_page
*sp
,
2381 struct kvm_mmu_page
*child
;
2384 if (is_shadow_present_pte(pte
)) {
2385 if (is_last_spte(pte
, sp
->role
.level
))
2386 rmap_remove(vcpu
->kvm
, spte
);
2388 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2389 mmu_page_remove_parent_pte(child
, spte
);
2392 __set_spte(spte
, shadow_trap_nonpresent_pte
);
2393 if (is_large_pte(pte
))
2394 --vcpu
->kvm
->stat
.lpages
;
2397 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
2398 struct kvm_mmu_page
*sp
,
2402 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
2403 if (!vcpu
->arch
.update_pte
.largepage
||
2404 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2405 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
2410 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
2411 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
2412 paging32_update_pte(vcpu
, sp
, spte
, new);
2414 paging64_update_pte(vcpu
, sp
, spte
, new);
2417 static bool need_remote_flush(u64 old
, u64
new)
2419 if (!is_shadow_present_pte(old
))
2421 if (!is_shadow_present_pte(new))
2423 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
2425 old
^= PT64_NX_MASK
;
2426 new ^= PT64_NX_MASK
;
2427 return (old
& ~new & PT64_PERM_MASK
) != 0;
2430 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
2432 if (need_remote_flush(old
, new))
2433 kvm_flush_remote_tlbs(vcpu
->kvm
);
2435 kvm_mmu_flush_tlb(vcpu
);
2438 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
2440 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2442 return !!(spte
&& (*spte
& shadow_accessed_mask
));
2445 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2446 const u8
*new, int bytes
)
2453 vcpu
->arch
.update_pte
.largepage
= 0;
2455 if (bytes
!= 4 && bytes
!= 8)
2459 * Assume that the pte write on a page table of the same type
2460 * as the current vcpu paging mode. This is nearly always true
2461 * (might be false while changing modes). Note it is verified later
2465 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2466 if ((bytes
== 4) && (gpa
% 4 == 0)) {
2467 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
2470 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
2471 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
2472 memcpy((void *)&gpte
, new, 8);
2475 if ((bytes
== 4) && (gpa
% 4 == 0))
2476 memcpy((void *)&gpte
, new, 4);
2478 if (!is_present_gpte(gpte
))
2480 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
2482 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
2483 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2484 vcpu
->arch
.update_pte
.largepage
= 1;
2486 vcpu
->arch
.update_pte
.mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2488 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2490 if (is_error_pfn(pfn
)) {
2491 kvm_release_pfn_clean(pfn
);
2494 vcpu
->arch
.update_pte
.gfn
= gfn
;
2495 vcpu
->arch
.update_pte
.pfn
= pfn
;
2498 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2500 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2503 && vcpu
->arch
.last_pte_gfn
== gfn
2504 && shadow_accessed_mask
2505 && !(*spte
& shadow_accessed_mask
)
2506 && is_shadow_present_pte(*spte
))
2507 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
2510 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2511 const u8
*new, int bytes
,
2512 bool guest_initiated
)
2514 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2515 struct kvm_mmu_page
*sp
;
2516 struct hlist_node
*node
, *n
;
2517 struct hlist_head
*bucket
;
2521 unsigned offset
= offset_in_page(gpa
);
2523 unsigned page_offset
;
2524 unsigned misaligned
;
2531 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
2532 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
2533 spin_lock(&vcpu
->kvm
->mmu_lock
);
2534 kvm_mmu_access_page(vcpu
, gfn
);
2535 kvm_mmu_free_some_pages(vcpu
);
2536 ++vcpu
->kvm
->stat
.mmu_pte_write
;
2537 kvm_mmu_audit(vcpu
, "pre pte write");
2538 if (guest_initiated
) {
2539 if (gfn
== vcpu
->arch
.last_pt_write_gfn
2540 && !last_updated_pte_accessed(vcpu
)) {
2541 ++vcpu
->arch
.last_pt_write_count
;
2542 if (vcpu
->arch
.last_pt_write_count
>= 3)
2545 vcpu
->arch
.last_pt_write_gfn
= gfn
;
2546 vcpu
->arch
.last_pt_write_count
= 1;
2547 vcpu
->arch
.last_pte_updated
= NULL
;
2550 index
= kvm_page_table_hashfn(gfn
);
2551 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
2552 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
2553 if (sp
->gfn
!= gfn
|| sp
->role
.direct
|| sp
->role
.invalid
)
2555 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
2556 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
2557 misaligned
|= bytes
< 4;
2558 if (misaligned
|| flooded
) {
2560 * Misaligned accesses are too much trouble to fix
2561 * up; also, they usually indicate a page is not used
2564 * If we're seeing too many writes to a page,
2565 * it may no longer be a page table, or we may be
2566 * forking, in which case it is better to unmap the
2569 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2570 gpa
, bytes
, sp
->role
.word
);
2571 if (kvm_mmu_zap_page(vcpu
->kvm
, sp
))
2573 ++vcpu
->kvm
->stat
.mmu_flooded
;
2576 page_offset
= offset
;
2577 level
= sp
->role
.level
;
2579 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2580 page_offset
<<= 1; /* 32->64 */
2582 * A 32-bit pde maps 4MB while the shadow pdes map
2583 * only 2MB. So we need to double the offset again
2584 * and zap two pdes instead of one.
2586 if (level
== PT32_ROOT_LEVEL
) {
2587 page_offset
&= ~7; /* kill rounding error */
2591 quadrant
= page_offset
>> PAGE_SHIFT
;
2592 page_offset
&= ~PAGE_MASK
;
2593 if (quadrant
!= sp
->role
.quadrant
)
2596 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
2597 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
2599 r
= kvm_read_guest_atomic(vcpu
->kvm
,
2600 gpa
& ~(u64
)(pte_size
- 1),
2602 new = (const void *)&gentry
;
2608 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
2610 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
2611 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
2615 kvm_mmu_audit(vcpu
, "post pte write");
2616 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2617 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
2618 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
2619 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2623 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
2628 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
2630 spin_lock(&vcpu
->kvm
->mmu_lock
);
2631 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
2632 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2635 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
2637 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
2639 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
2640 struct kvm_mmu_page
*sp
;
2642 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
2643 struct kvm_mmu_page
, link
);
2644 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2645 ++vcpu
->kvm
->stat
.mmu_recycled
;
2649 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
2652 enum emulation_result er
;
2654 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
2663 r
= mmu_topup_memory_caches(vcpu
);
2667 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
2672 case EMULATE_DO_MMIO
:
2673 ++vcpu
->stat
.mmio_exits
;
2676 vcpu
->run
->exit_reason
= KVM_EXIT_INTERNAL_ERROR
;
2677 vcpu
->run
->internal
.suberror
= KVM_INTERNAL_ERROR_EMULATION
;
2685 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
2687 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
2689 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
2690 kvm_mmu_flush_tlb(vcpu
);
2691 ++vcpu
->stat
.invlpg
;
2693 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
2695 void kvm_enable_tdp(void)
2699 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
2701 void kvm_disable_tdp(void)
2703 tdp_enabled
= false;
2705 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
2707 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
2709 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
2712 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
2719 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
2720 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2721 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
2723 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2724 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
2726 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2727 * Therefore we need to allocate shadow page tables in the first
2728 * 4GB of memory, which happens to fit the DMA32 zone.
2730 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
2733 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
2734 for (i
= 0; i
< 4; ++i
)
2735 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2740 free_mmu_pages(vcpu
);
2744 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
2747 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2749 return alloc_mmu_pages(vcpu
);
2752 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
2755 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2757 return init_kvm_mmu(vcpu
);
2760 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
2764 destroy_kvm_mmu(vcpu
);
2765 free_mmu_pages(vcpu
);
2766 mmu_free_memory_caches(vcpu
);
2769 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
2771 struct kvm_mmu_page
*sp
;
2773 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
2777 if (!test_bit(slot
, sp
->slot_bitmap
))
2781 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
2783 if (pt
[i
] & PT_WRITABLE_MASK
)
2784 pt
[i
] &= ~PT_WRITABLE_MASK
;
2786 kvm_flush_remote_tlbs(kvm
);
2789 void kvm_mmu_zap_all(struct kvm
*kvm
)
2791 struct kvm_mmu_page
*sp
, *node
;
2793 spin_lock(&kvm
->mmu_lock
);
2794 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
2795 if (kvm_mmu_zap_page(kvm
, sp
))
2796 node
= container_of(kvm
->arch
.active_mmu_pages
.next
,
2797 struct kvm_mmu_page
, link
);
2798 spin_unlock(&kvm
->mmu_lock
);
2800 kvm_flush_remote_tlbs(kvm
);
2803 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
2805 struct kvm_mmu_page
*page
;
2807 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
2808 struct kvm_mmu_page
, link
);
2809 kvm_mmu_zap_page(kvm
, page
);
2812 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
2815 struct kvm
*kvm_freed
= NULL
;
2816 int cache_count
= 0;
2818 spin_lock(&kvm_lock
);
2820 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
2823 if (!down_read_trylock(&kvm
->slots_lock
))
2825 spin_lock(&kvm
->mmu_lock
);
2826 npages
= kvm
->arch
.n_alloc_mmu_pages
-
2827 kvm
->arch
.n_free_mmu_pages
;
2828 cache_count
+= npages
;
2829 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
2830 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
2836 spin_unlock(&kvm
->mmu_lock
);
2837 up_read(&kvm
->slots_lock
);
2840 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
2842 spin_unlock(&kvm_lock
);
2847 static struct shrinker mmu_shrinker
= {
2848 .shrink
= mmu_shrink
,
2849 .seeks
= DEFAULT_SEEKS
* 10,
2852 static void mmu_destroy_caches(void)
2854 if (pte_chain_cache
)
2855 kmem_cache_destroy(pte_chain_cache
);
2856 if (rmap_desc_cache
)
2857 kmem_cache_destroy(rmap_desc_cache
);
2858 if (mmu_page_header_cache
)
2859 kmem_cache_destroy(mmu_page_header_cache
);
2862 void kvm_mmu_module_exit(void)
2864 mmu_destroy_caches();
2865 unregister_shrinker(&mmu_shrinker
);
2868 int kvm_mmu_module_init(void)
2870 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2871 sizeof(struct kvm_pte_chain
),
2873 if (!pte_chain_cache
)
2875 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2876 sizeof(struct kvm_rmap_desc
),
2878 if (!rmap_desc_cache
)
2881 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2882 sizeof(struct kvm_mmu_page
),
2884 if (!mmu_page_header_cache
)
2887 register_shrinker(&mmu_shrinker
);
2892 mmu_destroy_caches();
2897 * Caculate mmu pages needed for kvm.
2899 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2902 unsigned int nr_mmu_pages
;
2903 unsigned int nr_pages
= 0;
2905 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2906 nr_pages
+= kvm
->memslots
[i
].npages
;
2908 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2909 nr_mmu_pages
= max(nr_mmu_pages
,
2910 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2912 return nr_mmu_pages
;
2915 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2918 if (len
> buffer
->len
)
2923 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2928 ret
= pv_mmu_peek_buffer(buffer
, len
);
2933 buffer
->processed
+= len
;
2937 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2938 gpa_t addr
, gpa_t value
)
2943 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2946 r
= mmu_topup_memory_caches(vcpu
);
2950 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2956 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2958 kvm_set_cr3(vcpu
, vcpu
->arch
.cr3
);
2962 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2964 spin_lock(&vcpu
->kvm
->mmu_lock
);
2965 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2966 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2970 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2971 struct kvm_pv_mmu_op_buffer
*buffer
)
2973 struct kvm_mmu_op_header
*header
;
2975 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2978 switch (header
->op
) {
2979 case KVM_MMU_OP_WRITE_PTE
: {
2980 struct kvm_mmu_op_write_pte
*wpte
;
2982 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2985 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2988 case KVM_MMU_OP_FLUSH_TLB
: {
2989 struct kvm_mmu_op_flush_tlb
*ftlb
;
2991 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2994 return kvm_pv_mmu_flush_tlb(vcpu
);
2996 case KVM_MMU_OP_RELEASE_PT
: {
2997 struct kvm_mmu_op_release_pt
*rpt
;
2999 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
3002 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
3008 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
3009 gpa_t addr
, unsigned long *ret
)
3012 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
3014 buffer
->ptr
= buffer
->buf
;
3015 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
3016 buffer
->processed
= 0;
3018 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
3022 while (buffer
->len
) {
3023 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
3032 *ret
= buffer
->processed
;
3038 static const char *audit_msg
;
3040 static gva_t
canonicalize(gva_t gva
)
3042 #ifdef CONFIG_X86_64
3043 gva
= (long long)(gva
<< 16) >> 16;
3049 typedef void (*inspect_spte_fn
) (struct kvm
*kvm
, struct kvm_mmu_page
*sp
,
3052 static void __mmu_spte_walk(struct kvm
*kvm
, struct kvm_mmu_page
*sp
,
3057 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3058 u64 ent
= sp
->spt
[i
];
3060 if (is_shadow_present_pte(ent
)) {
3061 if (sp
->role
.level
> 1 && !is_large_pte(ent
)) {
3062 struct kvm_mmu_page
*child
;
3063 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
3064 __mmu_spte_walk(kvm
, child
, fn
);
3066 if (sp
->role
.level
== 1)
3067 fn(kvm
, sp
, &sp
->spt
[i
]);
3072 static void mmu_spte_walk(struct kvm_vcpu
*vcpu
, inspect_spte_fn fn
)
3075 struct kvm_mmu_page
*sp
;
3077 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
3079 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
3080 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
3081 sp
= page_header(root
);
3082 __mmu_spte_walk(vcpu
->kvm
, sp
, fn
);
3085 for (i
= 0; i
< 4; ++i
) {
3086 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
3088 if (root
&& VALID_PAGE(root
)) {
3089 root
&= PT64_BASE_ADDR_MASK
;
3090 sp
= page_header(root
);
3091 __mmu_spte_walk(vcpu
->kvm
, sp
, fn
);
3097 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
3098 gva_t va
, int level
)
3100 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
3102 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
3104 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
3107 if (ent
== shadow_trap_nonpresent_pte
)
3110 va
= canonicalize(va
);
3112 if (ent
== shadow_notrap_nonpresent_pte
)
3113 printk(KERN_ERR
"audit: (%s) nontrapping pte"
3114 " in nonleaf level: levels %d gva %lx"
3115 " level %d pte %llx\n", audit_msg
,
3116 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
3118 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
3120 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
3121 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
3122 pfn_t pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
3123 hpa_t hpa
= (hpa_t
)pfn
<< PAGE_SHIFT
;
3125 if (is_shadow_present_pte(ent
)
3126 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
3127 printk(KERN_ERR
"xx audit error: (%s) levels %d"
3128 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
3129 audit_msg
, vcpu
->arch
.mmu
.root_level
,
3131 is_shadow_present_pte(ent
));
3132 else if (ent
== shadow_notrap_nonpresent_pte
3133 && !is_error_hpa(hpa
))
3134 printk(KERN_ERR
"audit: (%s) notrap shadow,"
3135 " valid guest gva %lx\n", audit_msg
, va
);
3136 kvm_release_pfn_clean(pfn
);
3142 static void audit_mappings(struct kvm_vcpu
*vcpu
)
3146 if (vcpu
->arch
.mmu
.root_level
== 4)
3147 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
3149 for (i
= 0; i
< 4; ++i
)
3150 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
3151 audit_mappings_page(vcpu
,
3152 vcpu
->arch
.mmu
.pae_root
[i
],
3157 static int count_rmaps(struct kvm_vcpu
*vcpu
)
3162 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
3163 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
3164 struct kvm_rmap_desc
*d
;
3166 for (j
= 0; j
< m
->npages
; ++j
) {
3167 unsigned long *rmapp
= &m
->rmap
[j
];
3171 if (!(*rmapp
& 1)) {
3175 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
3177 for (k
= 0; k
< RMAP_EXT
; ++k
)
3189 void inspect_spte_has_rmap(struct kvm
*kvm
, struct kvm_mmu_page
*sp
, u64
*sptep
)
3191 unsigned long *rmapp
;
3192 struct kvm_mmu_page
*rev_sp
;
3195 if (*sptep
& PT_WRITABLE_MASK
) {
3196 rev_sp
= page_header(__pa(sptep
));
3197 gfn
= rev_sp
->gfns
[sptep
- rev_sp
->spt
];
3199 if (!gfn_to_memslot(kvm
, gfn
)) {
3200 if (!printk_ratelimit())
3202 printk(KERN_ERR
"%s: no memslot for gfn %ld\n",
3204 printk(KERN_ERR
"%s: index %ld of sp (gfn=%lx)\n",
3205 audit_msg
, sptep
- rev_sp
->spt
,
3211 rmapp
= gfn_to_rmap(kvm
, rev_sp
->gfns
[sptep
- rev_sp
->spt
], 0);
3213 if (!printk_ratelimit())
3215 printk(KERN_ERR
"%s: no rmap for writable spte %llx\n",
3223 void audit_writable_sptes_have_rmaps(struct kvm_vcpu
*vcpu
)
3225 mmu_spte_walk(vcpu
, inspect_spte_has_rmap
);
3228 static void check_writable_mappings_rmap(struct kvm_vcpu
*vcpu
)
3230 struct kvm_mmu_page
*sp
;
3233 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3236 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
3239 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3242 if (!(ent
& PT_PRESENT_MASK
))
3244 if (!(ent
& PT_WRITABLE_MASK
))
3246 inspect_spte_has_rmap(vcpu
->kvm
, sp
, &pt
[i
]);
3252 static void audit_rmap(struct kvm_vcpu
*vcpu
)
3254 check_writable_mappings_rmap(vcpu
);
3258 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
3260 struct kvm_mmu_page
*sp
;
3261 struct kvm_memory_slot
*slot
;
3262 unsigned long *rmapp
;
3265 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3266 if (sp
->role
.direct
)
3269 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
3270 slot
= gfn_to_memslot_unaliased(vcpu
->kvm
, sp
->gfn
);
3271 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
3273 printk(KERN_ERR
"%s: (%s) shadow page has writable"
3274 " mappings: gfn %lx role %x\n",
3275 __func__
, audit_msg
, sp
->gfn
,
3280 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
3287 audit_write_protection(vcpu
);
3288 audit_mappings(vcpu
);
3289 audit_writable_sptes_have_rmaps(vcpu
);