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.
22 #include <linux/kvm_host.h>
23 #include <linux/types.h>
24 #include <linux/string.h>
26 #include <linux/highmem.h>
27 #include <linux/module.h>
28 #include <linux/swap.h>
29 #include <linux/hugetlb.h>
30 #include <linux/compiler.h>
33 #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_iterator
{
156 #define for_each_shadow_entry(_vcpu, _addr, _walker) \
157 for (shadow_walk_init(&(_walker), _vcpu, _addr); \
158 shadow_walk_okay(&(_walker)); \
159 shadow_walk_next(&(_walker)))
162 struct kvm_unsync_walk
{
163 int (*entry
) (struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
);
166 typedef int (*mmu_parent_walk_fn
) (struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
);
168 static struct kmem_cache
*pte_chain_cache
;
169 static struct kmem_cache
*rmap_desc_cache
;
170 static struct kmem_cache
*mmu_page_header_cache
;
172 static u64 __read_mostly shadow_trap_nonpresent_pte
;
173 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
174 static u64 __read_mostly shadow_base_present_pte
;
175 static u64 __read_mostly shadow_nx_mask
;
176 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
177 static u64 __read_mostly shadow_user_mask
;
178 static u64 __read_mostly shadow_accessed_mask
;
179 static u64 __read_mostly shadow_dirty_mask
;
180 static u64 __read_mostly shadow_mt_mask
;
182 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
184 shadow_trap_nonpresent_pte
= trap_pte
;
185 shadow_notrap_nonpresent_pte
= notrap_pte
;
187 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
189 void kvm_mmu_set_base_ptes(u64 base_pte
)
191 shadow_base_present_pte
= base_pte
;
193 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes
);
195 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
196 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
, u64 mt_mask
)
198 shadow_user_mask
= user_mask
;
199 shadow_accessed_mask
= accessed_mask
;
200 shadow_dirty_mask
= dirty_mask
;
201 shadow_nx_mask
= nx_mask
;
202 shadow_x_mask
= x_mask
;
203 shadow_mt_mask
= mt_mask
;
205 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
207 static int is_write_protection(struct kvm_vcpu
*vcpu
)
209 return vcpu
->arch
.cr0
& X86_CR0_WP
;
212 static int is_cpuid_PSE36(void)
217 static int is_nx(struct kvm_vcpu
*vcpu
)
219 return vcpu
->arch
.shadow_efer
& EFER_NX
;
222 static int is_present_pte(unsigned long pte
)
224 return pte
& PT_PRESENT_MASK
;
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_pte(unsigned long pte
)
245 return pte
& shadow_dirty_mask
;
248 static int is_rmap_pte(u64 pte
)
250 return is_shadow_present_pte(pte
);
253 static pfn_t
spte_to_pfn(u64 pte
)
255 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
258 static gfn_t
pse36_gfn_delta(u32 gpte
)
260 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
262 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
265 static void set_shadow_pte(u64
*sptep
, u64 spte
)
268 set_64bit((unsigned long *)sptep
, spte
);
270 set_64bit((unsigned long long *)sptep
, spte
);
274 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
275 struct kmem_cache
*base_cache
, int min
)
279 if (cache
->nobjs
>= min
)
281 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
282 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
285 cache
->objects
[cache
->nobjs
++] = obj
;
290 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
293 kfree(mc
->objects
[--mc
->nobjs
]);
296 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
301 if (cache
->nobjs
>= min
)
303 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
304 page
= alloc_page(GFP_KERNEL
);
307 set_page_private(page
, 0);
308 cache
->objects
[cache
->nobjs
++] = page_address(page
);
313 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
316 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
319 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
323 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
327 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
331 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
334 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
335 mmu_page_header_cache
, 4);
340 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
342 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
343 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
344 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
345 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
348 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
354 p
= mc
->objects
[--mc
->nobjs
];
359 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
361 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
362 sizeof(struct kvm_pte_chain
));
365 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
370 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
372 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
373 sizeof(struct kvm_rmap_desc
));
376 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
382 * Return the pointer to the largepage write count for a given
383 * gfn, handling slots that are not large page aligned.
385 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
389 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
390 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
391 return &slot
->lpage_info
[idx
].write_count
;
394 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
398 gfn
= unalias_gfn(kvm
, gfn
);
399 write_count
= slot_largepage_idx(gfn
,
400 gfn_to_memslot_unaliased(kvm
, gfn
));
404 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
408 gfn
= unalias_gfn(kvm
, gfn
);
409 write_count
= slot_largepage_idx(gfn
,
410 gfn_to_memslot_unaliased(kvm
, gfn
));
412 WARN_ON(*write_count
< 0);
415 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
417 struct kvm_memory_slot
*slot
;
420 gfn
= unalias_gfn(kvm
, gfn
);
421 slot
= gfn_to_memslot_unaliased(kvm
, gfn
);
423 largepage_idx
= slot_largepage_idx(gfn
, slot
);
424 return *largepage_idx
;
430 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
432 struct vm_area_struct
*vma
;
436 addr
= gfn_to_hva(kvm
, gfn
);
437 if (kvm_is_error_hva(addr
))
440 down_read(¤t
->mm
->mmap_sem
);
441 vma
= find_vma(current
->mm
, addr
);
442 if (vma
&& is_vm_hugetlb_page(vma
))
444 up_read(¤t
->mm
->mmap_sem
);
449 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
451 struct kvm_memory_slot
*slot
;
453 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
456 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
459 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
460 if (slot
&& slot
->dirty_bitmap
)
467 * Take gfn and return the reverse mapping to it.
468 * Note: gfn must be unaliased before this function get called
471 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
473 struct kvm_memory_slot
*slot
;
476 slot
= gfn_to_memslot(kvm
, gfn
);
478 return &slot
->rmap
[gfn
- slot
->base_gfn
];
480 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
481 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
483 return &slot
->lpage_info
[idx
].rmap_pde
;
487 * Reverse mapping data structures:
489 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
490 * that points to page_address(page).
492 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
493 * containing more mappings.
495 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
497 struct kvm_mmu_page
*sp
;
498 struct kvm_rmap_desc
*desc
;
499 unsigned long *rmapp
;
502 if (!is_rmap_pte(*spte
))
504 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
505 sp
= page_header(__pa(spte
));
506 sp
->gfns
[spte
- sp
->spt
] = gfn
;
507 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
509 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
510 *rmapp
= (unsigned long)spte
;
511 } else if (!(*rmapp
& 1)) {
512 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
513 desc
= mmu_alloc_rmap_desc(vcpu
);
514 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
515 desc
->shadow_ptes
[1] = spte
;
516 *rmapp
= (unsigned long)desc
| 1;
518 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
519 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
520 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
522 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
523 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
526 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
528 desc
->shadow_ptes
[i
] = spte
;
532 static void rmap_desc_remove_entry(unsigned long *rmapp
,
533 struct kvm_rmap_desc
*desc
,
535 struct kvm_rmap_desc
*prev_desc
)
539 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
541 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
542 desc
->shadow_ptes
[j
] = NULL
;
545 if (!prev_desc
&& !desc
->more
)
546 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
549 prev_desc
->more
= desc
->more
;
551 *rmapp
= (unsigned long)desc
->more
| 1;
552 mmu_free_rmap_desc(desc
);
555 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
557 struct kvm_rmap_desc
*desc
;
558 struct kvm_rmap_desc
*prev_desc
;
559 struct kvm_mmu_page
*sp
;
561 unsigned long *rmapp
;
564 if (!is_rmap_pte(*spte
))
566 sp
= page_header(__pa(spte
));
567 pfn
= spte_to_pfn(*spte
);
568 if (*spte
& shadow_accessed_mask
)
569 kvm_set_pfn_accessed(pfn
);
570 if (is_writeble_pte(*spte
))
571 kvm_release_pfn_dirty(pfn
);
573 kvm_release_pfn_clean(pfn
);
574 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
576 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
578 } else if (!(*rmapp
& 1)) {
579 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
580 if ((u64
*)*rmapp
!= spte
) {
581 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
587 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
588 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
591 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
592 if (desc
->shadow_ptes
[i
] == spte
) {
593 rmap_desc_remove_entry(rmapp
,
605 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
607 struct kvm_rmap_desc
*desc
;
608 struct kvm_rmap_desc
*prev_desc
;
614 else if (!(*rmapp
& 1)) {
616 return (u64
*)*rmapp
;
619 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
623 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
624 if (prev_spte
== spte
)
625 return desc
->shadow_ptes
[i
];
626 prev_spte
= desc
->shadow_ptes
[i
];
633 static int rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
635 unsigned long *rmapp
;
637 int write_protected
= 0;
639 gfn
= unalias_gfn(kvm
, gfn
);
640 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
642 spte
= rmap_next(kvm
, rmapp
, NULL
);
645 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
646 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
647 if (is_writeble_pte(*spte
)) {
648 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
651 spte
= rmap_next(kvm
, rmapp
, spte
);
653 if (write_protected
) {
656 spte
= rmap_next(kvm
, rmapp
, NULL
);
657 pfn
= spte_to_pfn(*spte
);
658 kvm_set_pfn_dirty(pfn
);
661 /* check for huge page mappings */
662 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
663 spte
= rmap_next(kvm
, rmapp
, NULL
);
666 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
667 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
668 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
669 if (is_writeble_pte(*spte
)) {
670 rmap_remove(kvm
, spte
);
672 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
676 spte
= rmap_next(kvm
, rmapp
, spte
);
679 return write_protected
;
682 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
685 int need_tlb_flush
= 0;
687 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
688 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
689 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
690 rmap_remove(kvm
, spte
);
691 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
694 return need_tlb_flush
;
697 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
698 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
))
704 * If mmap_sem isn't taken, we can look the memslots with only
705 * the mmu_lock by skipping over the slots with userspace_addr == 0.
707 for (i
= 0; i
< kvm
->nmemslots
; i
++) {
708 struct kvm_memory_slot
*memslot
= &kvm
->memslots
[i
];
709 unsigned long start
= memslot
->userspace_addr
;
712 /* mmu_lock protects userspace_addr */
716 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
717 if (hva
>= start
&& hva
< end
) {
718 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
719 retval
|= handler(kvm
, &memslot
->rmap
[gfn_offset
]);
720 retval
|= handler(kvm
,
721 &memslot
->lpage_info
[
723 KVM_PAGES_PER_HPAGE
].rmap_pde
);
730 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
732 return kvm_handle_hva(kvm
, hva
, kvm_unmap_rmapp
);
735 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
740 /* always return old for EPT */
741 if (!shadow_accessed_mask
)
744 spte
= rmap_next(kvm
, rmapp
, NULL
);
748 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
749 _young
= _spte
& PT_ACCESSED_MASK
;
752 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
754 spte
= rmap_next(kvm
, rmapp
, spte
);
759 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
761 return kvm_handle_hva(kvm
, hva
, kvm_age_rmapp
);
765 static int is_empty_shadow_page(u64
*spt
)
770 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
771 if (is_shadow_present_pte(*pos
)) {
772 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
780 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
782 ASSERT(is_empty_shadow_page(sp
->spt
));
784 __free_page(virt_to_page(sp
->spt
));
785 __free_page(virt_to_page(sp
->gfns
));
787 ++kvm
->arch
.n_free_mmu_pages
;
790 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
792 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
795 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
798 struct kvm_mmu_page
*sp
;
800 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
801 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
802 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
803 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
804 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
805 INIT_LIST_HEAD(&sp
->oos_link
);
806 ASSERT(is_empty_shadow_page(sp
->spt
));
807 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
809 sp
->parent_pte
= parent_pte
;
810 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
814 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
815 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
817 struct kvm_pte_chain
*pte_chain
;
818 struct hlist_node
*node
;
823 if (!sp
->multimapped
) {
824 u64
*old
= sp
->parent_pte
;
827 sp
->parent_pte
= parent_pte
;
831 pte_chain
= mmu_alloc_pte_chain(vcpu
);
832 INIT_HLIST_HEAD(&sp
->parent_ptes
);
833 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
834 pte_chain
->parent_ptes
[0] = old
;
836 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
837 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
839 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
840 if (!pte_chain
->parent_ptes
[i
]) {
841 pte_chain
->parent_ptes
[i
] = parent_pte
;
845 pte_chain
= mmu_alloc_pte_chain(vcpu
);
847 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
848 pte_chain
->parent_ptes
[0] = parent_pte
;
851 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
854 struct kvm_pte_chain
*pte_chain
;
855 struct hlist_node
*node
;
858 if (!sp
->multimapped
) {
859 BUG_ON(sp
->parent_pte
!= parent_pte
);
860 sp
->parent_pte
= NULL
;
863 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
864 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
865 if (!pte_chain
->parent_ptes
[i
])
867 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
869 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
870 && pte_chain
->parent_ptes
[i
+ 1]) {
871 pte_chain
->parent_ptes
[i
]
872 = pte_chain
->parent_ptes
[i
+ 1];
875 pte_chain
->parent_ptes
[i
] = NULL
;
877 hlist_del(&pte_chain
->link
);
878 mmu_free_pte_chain(pte_chain
);
879 if (hlist_empty(&sp
->parent_ptes
)) {
881 sp
->parent_pte
= NULL
;
890 static void mmu_parent_walk(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
891 mmu_parent_walk_fn fn
)
893 struct kvm_pte_chain
*pte_chain
;
894 struct hlist_node
*node
;
895 struct kvm_mmu_page
*parent_sp
;
898 if (!sp
->multimapped
&& sp
->parent_pte
) {
899 parent_sp
= page_header(__pa(sp
->parent_pte
));
901 mmu_parent_walk(vcpu
, parent_sp
, fn
);
904 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
905 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
906 if (!pte_chain
->parent_ptes
[i
])
908 parent_sp
= page_header(__pa(pte_chain
->parent_ptes
[i
]));
910 mmu_parent_walk(vcpu
, parent_sp
, fn
);
914 static void kvm_mmu_update_unsync_bitmap(u64
*spte
)
917 struct kvm_mmu_page
*sp
= page_header(__pa(spte
));
919 index
= spte
- sp
->spt
;
920 if (!__test_and_set_bit(index
, sp
->unsync_child_bitmap
))
921 sp
->unsync_children
++;
922 WARN_ON(!sp
->unsync_children
);
925 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page
*sp
)
927 struct kvm_pte_chain
*pte_chain
;
928 struct hlist_node
*node
;
934 if (!sp
->multimapped
) {
935 kvm_mmu_update_unsync_bitmap(sp
->parent_pte
);
939 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
940 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
941 if (!pte_chain
->parent_ptes
[i
])
943 kvm_mmu_update_unsync_bitmap(pte_chain
->parent_ptes
[i
]);
947 static int unsync_walk_fn(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
949 kvm_mmu_update_parents_unsync(sp
);
953 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu
*vcpu
,
954 struct kvm_mmu_page
*sp
)
956 mmu_parent_walk(vcpu
, sp
, unsync_walk_fn
);
957 kvm_mmu_update_parents_unsync(sp
);
960 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
961 struct kvm_mmu_page
*sp
)
965 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
966 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
969 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
970 struct kvm_mmu_page
*sp
)
975 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
979 #define KVM_PAGE_ARRAY_NR 16
981 struct kvm_mmu_pages
{
982 struct mmu_page_and_offset
{
983 struct kvm_mmu_page
*sp
;
985 } page
[KVM_PAGE_ARRAY_NR
];
989 #define for_each_unsync_children(bitmap, idx) \
990 for (idx = find_first_bit(bitmap, 512); \
992 idx = find_next_bit(bitmap, 512, idx+1))
994 int mmu_pages_add(struct kvm_mmu_pages
*pvec
, struct kvm_mmu_page
*sp
,
1000 for (i
=0; i
< pvec
->nr
; i
++)
1001 if (pvec
->page
[i
].sp
== sp
)
1004 pvec
->page
[pvec
->nr
].sp
= sp
;
1005 pvec
->page
[pvec
->nr
].idx
= idx
;
1007 return (pvec
->nr
== KVM_PAGE_ARRAY_NR
);
1010 static int __mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1011 struct kvm_mmu_pages
*pvec
)
1013 int i
, ret
, nr_unsync_leaf
= 0;
1015 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
1016 u64 ent
= sp
->spt
[i
];
1018 if (is_shadow_present_pte(ent
) && !is_large_pte(ent
)) {
1019 struct kvm_mmu_page
*child
;
1020 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
1022 if (child
->unsync_children
) {
1023 if (mmu_pages_add(pvec
, child
, i
))
1026 ret
= __mmu_unsync_walk(child
, pvec
);
1028 __clear_bit(i
, sp
->unsync_child_bitmap
);
1030 nr_unsync_leaf
+= ret
;
1035 if (child
->unsync
) {
1037 if (mmu_pages_add(pvec
, child
, i
))
1043 if (find_first_bit(sp
->unsync_child_bitmap
, 512) == 512)
1044 sp
->unsync_children
= 0;
1046 return nr_unsync_leaf
;
1049 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1050 struct kvm_mmu_pages
*pvec
)
1052 if (!sp
->unsync_children
)
1055 mmu_pages_add(pvec
, sp
, 0);
1056 return __mmu_unsync_walk(sp
, pvec
);
1059 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
1062 struct hlist_head
*bucket
;
1063 struct kvm_mmu_page
*sp
;
1064 struct hlist_node
*node
;
1066 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1067 index
= kvm_page_table_hashfn(gfn
);
1068 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1069 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
1070 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
1071 && !sp
->role
.invalid
) {
1072 pgprintk("%s: found role %x\n",
1073 __func__
, sp
->role
.word
);
1079 static void kvm_unlink_unsync_global(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1081 list_del(&sp
->oos_link
);
1082 --kvm
->stat
.mmu_unsync_global
;
1085 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1087 WARN_ON(!sp
->unsync
);
1090 kvm_unlink_unsync_global(kvm
, sp
);
1091 --kvm
->stat
.mmu_unsync
;
1094 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
);
1096 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1098 if (sp
->role
.glevels
!= vcpu
->arch
.mmu
.root_level
) {
1099 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1103 if (rmap_write_protect(vcpu
->kvm
, sp
->gfn
))
1104 kvm_flush_remote_tlbs(vcpu
->kvm
);
1105 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1106 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1107 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1111 kvm_mmu_flush_tlb(vcpu
);
1115 struct mmu_page_path
{
1116 struct kvm_mmu_page
*parent
[PT64_ROOT_LEVEL
-1];
1117 unsigned int idx
[PT64_ROOT_LEVEL
-1];
1120 #define for_each_sp(pvec, sp, parents, i) \
1121 for (i = mmu_pages_next(&pvec, &parents, -1), \
1122 sp = pvec.page[i].sp; \
1123 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1124 i = mmu_pages_next(&pvec, &parents, i))
1126 int mmu_pages_next(struct kvm_mmu_pages
*pvec
, struct mmu_page_path
*parents
,
1131 for (n
= i
+1; n
< pvec
->nr
; n
++) {
1132 struct kvm_mmu_page
*sp
= pvec
->page
[n
].sp
;
1134 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1135 parents
->idx
[0] = pvec
->page
[n
].idx
;
1139 parents
->parent
[sp
->role
.level
-2] = sp
;
1140 parents
->idx
[sp
->role
.level
-1] = pvec
->page
[n
].idx
;
1146 void mmu_pages_clear_parents(struct mmu_page_path
*parents
)
1148 struct kvm_mmu_page
*sp
;
1149 unsigned int level
= 0;
1152 unsigned int idx
= parents
->idx
[level
];
1154 sp
= parents
->parent
[level
];
1158 --sp
->unsync_children
;
1159 WARN_ON((int)sp
->unsync_children
< 0);
1160 __clear_bit(idx
, sp
->unsync_child_bitmap
);
1162 } while (level
< PT64_ROOT_LEVEL
-1 && !sp
->unsync_children
);
1165 static void kvm_mmu_pages_init(struct kvm_mmu_page
*parent
,
1166 struct mmu_page_path
*parents
,
1167 struct kvm_mmu_pages
*pvec
)
1169 parents
->parent
[parent
->role
.level
-1] = NULL
;
1173 static void mmu_sync_children(struct kvm_vcpu
*vcpu
,
1174 struct kvm_mmu_page
*parent
)
1177 struct kvm_mmu_page
*sp
;
1178 struct mmu_page_path parents
;
1179 struct kvm_mmu_pages pages
;
1181 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1182 while (mmu_unsync_walk(parent
, &pages
)) {
1185 for_each_sp(pages
, sp
, parents
, i
)
1186 protected |= rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1189 kvm_flush_remote_tlbs(vcpu
->kvm
);
1191 for_each_sp(pages
, sp
, parents
, i
) {
1192 kvm_sync_page(vcpu
, sp
);
1193 mmu_pages_clear_parents(&parents
);
1195 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1196 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1200 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1208 union kvm_mmu_page_role role
;
1211 struct hlist_head
*bucket
;
1212 struct kvm_mmu_page
*sp
;
1213 struct hlist_node
*node
, *tmp
;
1215 role
= vcpu
->arch
.mmu
.base_role
;
1217 role
.metaphysical
= metaphysical
;
1218 role
.access
= access
;
1219 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1220 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1221 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1222 role
.quadrant
= quadrant
;
1224 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
1226 index
= kvm_page_table_hashfn(gfn
);
1227 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1228 hlist_for_each_entry_safe(sp
, node
, tmp
, bucket
, hash_link
)
1229 if (sp
->gfn
== gfn
) {
1231 if (kvm_sync_page(vcpu
, sp
))
1234 if (sp
->role
.word
!= role
.word
)
1237 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1238 if (sp
->unsync_children
) {
1239 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
1240 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1242 pgprintk("%s: found\n", __func__
);
1245 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1246 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
1249 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
1252 sp
->global
= role
.cr4_pge
;
1253 hlist_add_head(&sp
->hash_link
, bucket
);
1254 if (!metaphysical
) {
1255 if (rmap_write_protect(vcpu
->kvm
, gfn
))
1256 kvm_flush_remote_tlbs(vcpu
->kvm
);
1257 account_shadowed(vcpu
->kvm
, gfn
);
1259 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1260 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1262 nonpaging_prefetch_page(vcpu
, sp
);
1266 static void shadow_walk_init(struct kvm_shadow_walk_iterator
*iterator
,
1267 struct kvm_vcpu
*vcpu
, u64 addr
)
1269 iterator
->addr
= addr
;
1270 iterator
->shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1271 iterator
->level
= vcpu
->arch
.mmu
.shadow_root_level
;
1272 if (iterator
->level
== PT32E_ROOT_LEVEL
) {
1273 iterator
->shadow_addr
1274 = vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1275 iterator
->shadow_addr
&= PT64_BASE_ADDR_MASK
;
1277 if (!iterator
->shadow_addr
)
1278 iterator
->level
= 0;
1282 static bool shadow_walk_okay(struct kvm_shadow_walk_iterator
*iterator
)
1284 if (iterator
->level
< PT_PAGE_TABLE_LEVEL
)
1286 iterator
->index
= SHADOW_PT_INDEX(iterator
->addr
, iterator
->level
);
1287 iterator
->sptep
= ((u64
*)__va(iterator
->shadow_addr
)) + iterator
->index
;
1291 static void shadow_walk_next(struct kvm_shadow_walk_iterator
*iterator
)
1293 iterator
->shadow_addr
= *iterator
->sptep
& PT64_BASE_ADDR_MASK
;
1297 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1298 struct kvm_mmu_page
*sp
)
1306 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1307 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1308 if (is_shadow_present_pte(pt
[i
]))
1309 rmap_remove(kvm
, &pt
[i
]);
1310 pt
[i
] = shadow_trap_nonpresent_pte
;
1315 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1318 if (is_shadow_present_pte(ent
)) {
1319 if (!is_large_pte(ent
)) {
1320 ent
&= PT64_BASE_ADDR_MASK
;
1321 mmu_page_remove_parent_pte(page_header(ent
),
1325 rmap_remove(kvm
, &pt
[i
]);
1328 pt
[i
] = shadow_trap_nonpresent_pte
;
1332 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1334 mmu_page_remove_parent_pte(sp
, parent_pte
);
1337 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1341 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
1343 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
1346 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1350 while (sp
->multimapped
|| sp
->parent_pte
) {
1351 if (!sp
->multimapped
)
1352 parent_pte
= sp
->parent_pte
;
1354 struct kvm_pte_chain
*chain
;
1356 chain
= container_of(sp
->parent_ptes
.first
,
1357 struct kvm_pte_chain
, link
);
1358 parent_pte
= chain
->parent_ptes
[0];
1360 BUG_ON(!parent_pte
);
1361 kvm_mmu_put_page(sp
, parent_pte
);
1362 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
1366 static int mmu_zap_unsync_children(struct kvm
*kvm
,
1367 struct kvm_mmu_page
*parent
)
1370 struct mmu_page_path parents
;
1371 struct kvm_mmu_pages pages
;
1373 if (parent
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1376 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1377 while (mmu_unsync_walk(parent
, &pages
)) {
1378 struct kvm_mmu_page
*sp
;
1380 for_each_sp(pages
, sp
, parents
, i
) {
1381 kvm_mmu_zap_page(kvm
, sp
);
1382 mmu_pages_clear_parents(&parents
);
1385 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1391 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1394 ++kvm
->stat
.mmu_shadow_zapped
;
1395 ret
= mmu_zap_unsync_children(kvm
, sp
);
1396 kvm_mmu_page_unlink_children(kvm
, sp
);
1397 kvm_mmu_unlink_parents(kvm
, sp
);
1398 kvm_flush_remote_tlbs(kvm
);
1399 if (!sp
->role
.invalid
&& !sp
->role
.metaphysical
)
1400 unaccount_shadowed(kvm
, sp
->gfn
);
1402 kvm_unlink_unsync_page(kvm
, sp
);
1403 if (!sp
->root_count
) {
1404 hlist_del(&sp
->hash_link
);
1405 kvm_mmu_free_page(kvm
, sp
);
1407 sp
->role
.invalid
= 1;
1408 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1409 kvm_reload_remote_mmus(kvm
);
1411 kvm_mmu_reset_last_pte_updated(kvm
);
1416 * Changing the number of mmu pages allocated to the vm
1417 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1419 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
1422 * If we set the number of mmu pages to be smaller be than the
1423 * number of actived pages , we must to free some mmu pages before we
1427 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
1429 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
1430 - kvm
->arch
.n_free_mmu_pages
;
1432 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
1433 struct kvm_mmu_page
*page
;
1435 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1436 struct kvm_mmu_page
, link
);
1437 kvm_mmu_zap_page(kvm
, page
);
1440 kvm
->arch
.n_free_mmu_pages
= 0;
1443 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
1444 - kvm
->arch
.n_alloc_mmu_pages
;
1446 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
1449 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1452 struct hlist_head
*bucket
;
1453 struct kvm_mmu_page
*sp
;
1454 struct hlist_node
*node
, *n
;
1457 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1459 index
= kvm_page_table_hashfn(gfn
);
1460 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1461 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
1462 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
1463 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
1466 if (kvm_mmu_zap_page(kvm
, sp
))
1472 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1475 struct hlist_head
*bucket
;
1476 struct kvm_mmu_page
*sp
;
1477 struct hlist_node
*node
, *nn
;
1479 index
= kvm_page_table_hashfn(gfn
);
1480 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1481 hlist_for_each_entry_safe(sp
, node
, nn
, bucket
, hash_link
) {
1482 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
1483 && !sp
->role
.invalid
) {
1484 pgprintk("%s: zap %lx %x\n",
1485 __func__
, gfn
, sp
->role
.word
);
1486 kvm_mmu_zap_page(kvm
, sp
);
1491 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1493 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1494 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1496 __set_bit(slot
, sp
->slot_bitmap
);
1499 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1504 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1507 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1508 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1509 set_shadow_pte(&pt
[i
], shadow_trap_nonpresent_pte
);
1513 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1517 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1519 if (gpa
== UNMAPPED_GVA
)
1522 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1528 * The function is based on mtrr_type_lookup() in
1529 * arch/x86/kernel/cpu/mtrr/generic.c
1531 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1536 u8 prev_match
, curr_match
;
1537 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1539 if (!mtrr_state
->enabled
)
1542 /* Make end inclusive end, instead of exclusive */
1545 /* Look in fixed ranges. Just return the type as per start */
1546 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1549 if (start
< 0x80000) {
1551 idx
+= (start
>> 16);
1552 return mtrr_state
->fixed_ranges
[idx
];
1553 } else if (start
< 0xC0000) {
1555 idx
+= ((start
- 0x80000) >> 14);
1556 return mtrr_state
->fixed_ranges
[idx
];
1557 } else if (start
< 0x1000000) {
1559 idx
+= ((start
- 0xC0000) >> 12);
1560 return mtrr_state
->fixed_ranges
[idx
];
1565 * Look in variable ranges
1566 * Look of multiple ranges matching this address and pick type
1567 * as per MTRR precedence
1569 if (!(mtrr_state
->enabled
& 2))
1570 return mtrr_state
->def_type
;
1573 for (i
= 0; i
< num_var_ranges
; ++i
) {
1574 unsigned short start_state
, end_state
;
1576 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1579 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1580 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1581 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1582 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1584 start_state
= ((start
& mask
) == (base
& mask
));
1585 end_state
= ((end
& mask
) == (base
& mask
));
1586 if (start_state
!= end_state
)
1589 if ((start
& mask
) != (base
& mask
))
1592 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1593 if (prev_match
== 0xFF) {
1594 prev_match
= curr_match
;
1598 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1599 curr_match
== MTRR_TYPE_UNCACHABLE
)
1600 return MTRR_TYPE_UNCACHABLE
;
1602 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1603 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1604 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1605 curr_match
== MTRR_TYPE_WRBACK
)) {
1606 prev_match
= MTRR_TYPE_WRTHROUGH
;
1607 curr_match
= MTRR_TYPE_WRTHROUGH
;
1610 if (prev_match
!= curr_match
)
1611 return MTRR_TYPE_UNCACHABLE
;
1614 if (prev_match
!= 0xFF)
1617 return mtrr_state
->def_type
;
1620 static u8
get_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1624 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1625 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1626 if (mtrr
== 0xfe || mtrr
== 0xff)
1627 mtrr
= MTRR_TYPE_WRBACK
;
1631 static int kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1634 struct hlist_head
*bucket
;
1635 struct kvm_mmu_page
*s
;
1636 struct hlist_node
*node
, *n
;
1638 index
= kvm_page_table_hashfn(sp
->gfn
);
1639 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1640 /* don't unsync if pagetable is shadowed with multiple roles */
1641 hlist_for_each_entry_safe(s
, node
, n
, bucket
, hash_link
) {
1642 if (s
->gfn
!= sp
->gfn
|| s
->role
.metaphysical
)
1644 if (s
->role
.word
!= sp
->role
.word
)
1647 ++vcpu
->kvm
->stat
.mmu_unsync
;
1651 list_add(&sp
->oos_link
, &vcpu
->kvm
->arch
.oos_global_pages
);
1652 ++vcpu
->kvm
->stat
.mmu_unsync_global
;
1654 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1656 mmu_convert_notrap(sp
);
1660 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1663 struct kvm_mmu_page
*shadow
;
1665 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1667 if (shadow
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1671 if (can_unsync
&& oos_shadow
)
1672 return kvm_unsync_page(vcpu
, shadow
);
1678 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1679 unsigned pte_access
, int user_fault
,
1680 int write_fault
, int dirty
, int largepage
,
1681 int global
, gfn_t gfn
, pfn_t pfn
, bool speculative
,
1686 u64 mt_mask
= shadow_mt_mask
;
1687 struct kvm_mmu_page
*sp
= page_header(__pa(shadow_pte
));
1689 if (!global
&& sp
->global
) {
1692 kvm_unlink_unsync_global(vcpu
->kvm
, sp
);
1693 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1698 * We don't set the accessed bit, since we sometimes want to see
1699 * whether the guest actually used the pte (in order to detect
1702 spte
= shadow_base_present_pte
| shadow_dirty_mask
;
1704 spte
|= shadow_accessed_mask
;
1706 pte_access
&= ~ACC_WRITE_MASK
;
1707 if (pte_access
& ACC_EXEC_MASK
)
1708 spte
|= shadow_x_mask
;
1710 spte
|= shadow_nx_mask
;
1711 if (pte_access
& ACC_USER_MASK
)
1712 spte
|= shadow_user_mask
;
1714 spte
|= PT_PAGE_SIZE_MASK
;
1716 if (!kvm_is_mmio_pfn(pfn
)) {
1717 mt_mask
= get_memory_type(vcpu
, gfn
) <<
1718 kvm_x86_ops
->get_mt_mask_shift();
1719 mt_mask
|= VMX_EPT_IGMT_BIT
;
1721 mt_mask
= MTRR_TYPE_UNCACHABLE
<<
1722 kvm_x86_ops
->get_mt_mask_shift();
1726 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1728 if ((pte_access
& ACC_WRITE_MASK
)
1729 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1731 if (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
)) {
1733 spte
= shadow_trap_nonpresent_pte
;
1737 spte
|= PT_WRITABLE_MASK
;
1740 * Optimization: for pte sync, if spte was writable the hash
1741 * lookup is unnecessary (and expensive). Write protection
1742 * is responsibility of mmu_get_page / kvm_sync_page.
1743 * Same reasoning can be applied to dirty page accounting.
1745 if (!can_unsync
&& is_writeble_pte(*shadow_pte
))
1748 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1749 pgprintk("%s: found shadow page for %lx, marking ro\n",
1752 pte_access
&= ~ACC_WRITE_MASK
;
1753 if (is_writeble_pte(spte
))
1754 spte
&= ~PT_WRITABLE_MASK
;
1758 if (pte_access
& ACC_WRITE_MASK
)
1759 mark_page_dirty(vcpu
->kvm
, gfn
);
1762 set_shadow_pte(shadow_pte
, spte
);
1766 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1767 unsigned pt_access
, unsigned pte_access
,
1768 int user_fault
, int write_fault
, int dirty
,
1769 int *ptwrite
, int largepage
, int global
,
1770 gfn_t gfn
, pfn_t pfn
, bool speculative
)
1772 int was_rmapped
= 0;
1773 int was_writeble
= is_writeble_pte(*shadow_pte
);
1775 pgprintk("%s: spte %llx access %x write_fault %d"
1776 " user_fault %d gfn %lx\n",
1777 __func__
, *shadow_pte
, pt_access
,
1778 write_fault
, user_fault
, gfn
);
1780 if (is_rmap_pte(*shadow_pte
)) {
1782 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1783 * the parent of the now unreachable PTE.
1785 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1786 struct kvm_mmu_page
*child
;
1787 u64 pte
= *shadow_pte
;
1789 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1790 mmu_page_remove_parent_pte(child
, shadow_pte
);
1791 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1792 pgprintk("hfn old %lx new %lx\n",
1793 spte_to_pfn(*shadow_pte
), pfn
);
1794 rmap_remove(vcpu
->kvm
, shadow_pte
);
1797 was_rmapped
= is_large_pte(*shadow_pte
);
1802 if (set_spte(vcpu
, shadow_pte
, pte_access
, user_fault
, write_fault
,
1803 dirty
, largepage
, global
, gfn
, pfn
, speculative
, true)) {
1806 kvm_x86_ops
->tlb_flush(vcpu
);
1809 pgprintk("%s: setting spte %llx\n", __func__
, *shadow_pte
);
1810 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1811 is_large_pte(*shadow_pte
)? "2MB" : "4kB",
1812 is_present_pte(*shadow_pte
)?"RW":"R", gfn
,
1813 *shadow_pte
, shadow_pte
);
1814 if (!was_rmapped
&& is_large_pte(*shadow_pte
))
1815 ++vcpu
->kvm
->stat
.lpages
;
1817 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1819 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1820 if (!is_rmap_pte(*shadow_pte
))
1821 kvm_release_pfn_clean(pfn
);
1824 kvm_release_pfn_dirty(pfn
);
1826 kvm_release_pfn_clean(pfn
);
1829 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1830 vcpu
->arch
.last_pte_gfn
= gfn
;
1834 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1838 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1839 int largepage
, gfn_t gfn
, pfn_t pfn
)
1841 struct kvm_shadow_walk_iterator iterator
;
1842 struct kvm_mmu_page
*sp
;
1846 for_each_shadow_entry(vcpu
, (u64
)gfn
<< PAGE_SHIFT
, iterator
) {
1847 if (iterator
.level
== PT_PAGE_TABLE_LEVEL
1848 || (largepage
&& iterator
.level
== PT_DIRECTORY_LEVEL
)) {
1849 mmu_set_spte(vcpu
, iterator
.sptep
, ACC_ALL
, ACC_ALL
,
1850 0, write
, 1, &pt_write
,
1851 largepage
, 0, gfn
, pfn
, false);
1852 ++vcpu
->stat
.pf_fixed
;
1856 if (*iterator
.sptep
== shadow_trap_nonpresent_pte
) {
1857 pseudo_gfn
= (iterator
.addr
& PT64_DIR_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1858 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, iterator
.addr
,
1860 1, ACC_ALL
, iterator
.sptep
);
1862 pgprintk("nonpaging_map: ENOMEM\n");
1863 kvm_release_pfn_clean(pfn
);
1867 set_shadow_pte(iterator
.sptep
,
1869 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1870 | shadow_user_mask
| shadow_x_mask
);
1876 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1881 unsigned long mmu_seq
;
1883 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1884 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1888 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1890 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1893 if (is_error_pfn(pfn
)) {
1894 kvm_release_pfn_clean(pfn
);
1898 spin_lock(&vcpu
->kvm
->mmu_lock
);
1899 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1901 kvm_mmu_free_some_pages(vcpu
);
1902 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
);
1903 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1909 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1910 kvm_release_pfn_clean(pfn
);
1915 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1918 struct kvm_mmu_page
*sp
;
1920 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1922 spin_lock(&vcpu
->kvm
->mmu_lock
);
1923 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1924 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1926 sp
= page_header(root
);
1928 if (!sp
->root_count
&& sp
->role
.invalid
)
1929 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1930 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1931 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1934 for (i
= 0; i
< 4; ++i
) {
1935 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1938 root
&= PT64_BASE_ADDR_MASK
;
1939 sp
= page_header(root
);
1941 if (!sp
->root_count
&& sp
->role
.invalid
)
1942 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1944 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1946 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1947 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1950 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1954 struct kvm_mmu_page
*sp
;
1955 int metaphysical
= 0;
1957 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1959 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1960 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1962 ASSERT(!VALID_PAGE(root
));
1965 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1966 PT64_ROOT_LEVEL
, metaphysical
,
1968 root
= __pa(sp
->spt
);
1970 vcpu
->arch
.mmu
.root_hpa
= root
;
1973 metaphysical
= !is_paging(vcpu
);
1976 for (i
= 0; i
< 4; ++i
) {
1977 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1979 ASSERT(!VALID_PAGE(root
));
1980 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1981 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1982 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1985 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1986 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1988 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1989 PT32_ROOT_LEVEL
, metaphysical
,
1991 root
= __pa(sp
->spt
);
1993 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1995 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1998 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2001 struct kvm_mmu_page
*sp
;
2003 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2005 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2006 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2007 sp
= page_header(root
);
2008 mmu_sync_children(vcpu
, sp
);
2011 for (i
= 0; i
< 4; ++i
) {
2012 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2015 root
&= PT64_BASE_ADDR_MASK
;
2016 sp
= page_header(root
);
2017 mmu_sync_children(vcpu
, sp
);
2022 static void mmu_sync_global(struct kvm_vcpu
*vcpu
)
2024 struct kvm
*kvm
= vcpu
->kvm
;
2025 struct kvm_mmu_page
*sp
, *n
;
2027 list_for_each_entry_safe(sp
, n
, &kvm
->arch
.oos_global_pages
, oos_link
)
2028 kvm_sync_page(vcpu
, sp
);
2031 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2033 spin_lock(&vcpu
->kvm
->mmu_lock
);
2034 mmu_sync_roots(vcpu
);
2035 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2038 void kvm_mmu_sync_global(struct kvm_vcpu
*vcpu
)
2040 spin_lock(&vcpu
->kvm
->mmu_lock
);
2041 mmu_sync_global(vcpu
);
2042 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2045 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
2050 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
2056 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
2057 r
= mmu_topup_memory_caches(vcpu
);
2062 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2064 gfn
= gva
>> PAGE_SHIFT
;
2066 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
2067 error_code
& PFERR_WRITE_MASK
, gfn
);
2070 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
2076 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2077 unsigned long mmu_seq
;
2080 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2082 r
= mmu_topup_memory_caches(vcpu
);
2086 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
2087 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2090 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2092 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2093 if (is_error_pfn(pfn
)) {
2094 kvm_release_pfn_clean(pfn
);
2097 spin_lock(&vcpu
->kvm
->mmu_lock
);
2098 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2100 kvm_mmu_free_some_pages(vcpu
);
2101 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
2102 largepage
, gfn
, pfn
);
2103 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2108 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2109 kvm_release_pfn_clean(pfn
);
2113 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
2115 mmu_free_roots(vcpu
);
2118 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
2120 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2122 context
->new_cr3
= nonpaging_new_cr3
;
2123 context
->page_fault
= nonpaging_page_fault
;
2124 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2125 context
->free
= nonpaging_free
;
2126 context
->prefetch_page
= nonpaging_prefetch_page
;
2127 context
->sync_page
= nonpaging_sync_page
;
2128 context
->invlpg
= nonpaging_invlpg
;
2129 context
->root_level
= 0;
2130 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2131 context
->root_hpa
= INVALID_PAGE
;
2135 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2137 ++vcpu
->stat
.tlb_flush
;
2138 kvm_x86_ops
->tlb_flush(vcpu
);
2141 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2143 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
2144 mmu_free_roots(vcpu
);
2147 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2151 kvm_inject_page_fault(vcpu
, addr
, err_code
);
2154 static void paging_free(struct kvm_vcpu
*vcpu
)
2156 nonpaging_free(vcpu
);
2160 #include "paging_tmpl.h"
2164 #include "paging_tmpl.h"
2167 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
2169 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2171 ASSERT(is_pae(vcpu
));
2172 context
->new_cr3
= paging_new_cr3
;
2173 context
->page_fault
= paging64_page_fault
;
2174 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2175 context
->prefetch_page
= paging64_prefetch_page
;
2176 context
->sync_page
= paging64_sync_page
;
2177 context
->invlpg
= paging64_invlpg
;
2178 context
->free
= paging_free
;
2179 context
->root_level
= level
;
2180 context
->shadow_root_level
= level
;
2181 context
->root_hpa
= INVALID_PAGE
;
2185 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
2187 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
2190 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
2192 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2194 context
->new_cr3
= paging_new_cr3
;
2195 context
->page_fault
= paging32_page_fault
;
2196 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2197 context
->free
= paging_free
;
2198 context
->prefetch_page
= paging32_prefetch_page
;
2199 context
->sync_page
= paging32_sync_page
;
2200 context
->invlpg
= paging32_invlpg
;
2201 context
->root_level
= PT32_ROOT_LEVEL
;
2202 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2203 context
->root_hpa
= INVALID_PAGE
;
2207 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
2209 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
2212 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2214 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2216 context
->new_cr3
= nonpaging_new_cr3
;
2217 context
->page_fault
= tdp_page_fault
;
2218 context
->free
= nonpaging_free
;
2219 context
->prefetch_page
= nonpaging_prefetch_page
;
2220 context
->sync_page
= nonpaging_sync_page
;
2221 context
->invlpg
= nonpaging_invlpg
;
2222 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2223 context
->root_hpa
= INVALID_PAGE
;
2225 if (!is_paging(vcpu
)) {
2226 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2227 context
->root_level
= 0;
2228 } else if (is_long_mode(vcpu
)) {
2229 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2230 context
->root_level
= PT64_ROOT_LEVEL
;
2231 } else if (is_pae(vcpu
)) {
2232 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2233 context
->root_level
= PT32E_ROOT_LEVEL
;
2235 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2236 context
->root_level
= PT32_ROOT_LEVEL
;
2242 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2247 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2249 if (!is_paging(vcpu
))
2250 r
= nonpaging_init_context(vcpu
);
2251 else if (is_long_mode(vcpu
))
2252 r
= paging64_init_context(vcpu
);
2253 else if (is_pae(vcpu
))
2254 r
= paging32E_init_context(vcpu
);
2256 r
= paging32_init_context(vcpu
);
2258 vcpu
->arch
.mmu
.base_role
.glevels
= vcpu
->arch
.mmu
.root_level
;
2263 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
2265 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2268 return init_kvm_tdp_mmu(vcpu
);
2270 return init_kvm_softmmu(vcpu
);
2273 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
2276 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
2277 vcpu
->arch
.mmu
.free(vcpu
);
2278 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2282 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
2284 destroy_kvm_mmu(vcpu
);
2285 return init_kvm_mmu(vcpu
);
2287 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
2289 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
2293 r
= mmu_topup_memory_caches(vcpu
);
2296 spin_lock(&vcpu
->kvm
->mmu_lock
);
2297 kvm_mmu_free_some_pages(vcpu
);
2298 mmu_alloc_roots(vcpu
);
2299 mmu_sync_roots(vcpu
);
2300 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2301 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
2302 kvm_mmu_flush_tlb(vcpu
);
2306 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
2308 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
2310 mmu_free_roots(vcpu
);
2313 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
2314 struct kvm_mmu_page
*sp
,
2318 struct kvm_mmu_page
*child
;
2321 if (is_shadow_present_pte(pte
)) {
2322 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
2324 rmap_remove(vcpu
->kvm
, spte
);
2326 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2327 mmu_page_remove_parent_pte(child
, spte
);
2330 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
2331 if (is_large_pte(pte
))
2332 --vcpu
->kvm
->stat
.lpages
;
2335 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
2336 struct kvm_mmu_page
*sp
,
2340 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
2341 if (!vcpu
->arch
.update_pte
.largepage
||
2342 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2343 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
2348 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
2349 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
2350 paging32_update_pte(vcpu
, sp
, spte
, new);
2352 paging64_update_pte(vcpu
, sp
, spte
, new);
2355 static bool need_remote_flush(u64 old
, u64
new)
2357 if (!is_shadow_present_pte(old
))
2359 if (!is_shadow_present_pte(new))
2361 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
2363 old
^= PT64_NX_MASK
;
2364 new ^= PT64_NX_MASK
;
2365 return (old
& ~new & PT64_PERM_MASK
) != 0;
2368 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
2370 if (need_remote_flush(old
, new))
2371 kvm_flush_remote_tlbs(vcpu
->kvm
);
2373 kvm_mmu_flush_tlb(vcpu
);
2376 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
2378 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2380 return !!(spte
&& (*spte
& shadow_accessed_mask
));
2383 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2384 const u8
*new, int bytes
)
2391 vcpu
->arch
.update_pte
.largepage
= 0;
2393 if (bytes
!= 4 && bytes
!= 8)
2397 * Assume that the pte write on a page table of the same type
2398 * as the current vcpu paging mode. This is nearly always true
2399 * (might be false while changing modes). Note it is verified later
2403 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2404 if ((bytes
== 4) && (gpa
% 4 == 0)) {
2405 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
2408 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
2409 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
2410 memcpy((void *)&gpte
, new, 8);
2413 if ((bytes
== 4) && (gpa
% 4 == 0))
2414 memcpy((void *)&gpte
, new, 4);
2416 if (!is_present_pte(gpte
))
2418 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
2420 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
2421 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2422 vcpu
->arch
.update_pte
.largepage
= 1;
2424 vcpu
->arch
.update_pte
.mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2426 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2428 if (is_error_pfn(pfn
)) {
2429 kvm_release_pfn_clean(pfn
);
2432 vcpu
->arch
.update_pte
.gfn
= gfn
;
2433 vcpu
->arch
.update_pte
.pfn
= pfn
;
2436 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2438 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2441 && vcpu
->arch
.last_pte_gfn
== gfn
2442 && shadow_accessed_mask
2443 && !(*spte
& shadow_accessed_mask
)
2444 && is_shadow_present_pte(*spte
))
2445 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
2448 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2449 const u8
*new, int bytes
,
2450 bool guest_initiated
)
2452 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2453 struct kvm_mmu_page
*sp
;
2454 struct hlist_node
*node
, *n
;
2455 struct hlist_head
*bucket
;
2459 unsigned offset
= offset_in_page(gpa
);
2461 unsigned page_offset
;
2462 unsigned misaligned
;
2469 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
2470 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
2471 spin_lock(&vcpu
->kvm
->mmu_lock
);
2472 kvm_mmu_access_page(vcpu
, gfn
);
2473 kvm_mmu_free_some_pages(vcpu
);
2474 ++vcpu
->kvm
->stat
.mmu_pte_write
;
2475 kvm_mmu_audit(vcpu
, "pre pte write");
2476 if (guest_initiated
) {
2477 if (gfn
== vcpu
->arch
.last_pt_write_gfn
2478 && !last_updated_pte_accessed(vcpu
)) {
2479 ++vcpu
->arch
.last_pt_write_count
;
2480 if (vcpu
->arch
.last_pt_write_count
>= 3)
2483 vcpu
->arch
.last_pt_write_gfn
= gfn
;
2484 vcpu
->arch
.last_pt_write_count
= 1;
2485 vcpu
->arch
.last_pte_updated
= NULL
;
2488 index
= kvm_page_table_hashfn(gfn
);
2489 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
2490 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
2491 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
|| sp
->role
.invalid
)
2493 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
2494 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
2495 misaligned
|= bytes
< 4;
2496 if (misaligned
|| flooded
) {
2498 * Misaligned accesses are too much trouble to fix
2499 * up; also, they usually indicate a page is not used
2502 * If we're seeing too many writes to a page,
2503 * it may no longer be a page table, or we may be
2504 * forking, in which case it is better to unmap the
2507 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2508 gpa
, bytes
, sp
->role
.word
);
2509 if (kvm_mmu_zap_page(vcpu
->kvm
, sp
))
2511 ++vcpu
->kvm
->stat
.mmu_flooded
;
2514 page_offset
= offset
;
2515 level
= sp
->role
.level
;
2517 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2518 page_offset
<<= 1; /* 32->64 */
2520 * A 32-bit pde maps 4MB while the shadow pdes map
2521 * only 2MB. So we need to double the offset again
2522 * and zap two pdes instead of one.
2524 if (level
== PT32_ROOT_LEVEL
) {
2525 page_offset
&= ~7; /* kill rounding error */
2529 quadrant
= page_offset
>> PAGE_SHIFT
;
2530 page_offset
&= ~PAGE_MASK
;
2531 if (quadrant
!= sp
->role
.quadrant
)
2534 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
2535 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
2537 r
= kvm_read_guest_atomic(vcpu
->kvm
,
2538 gpa
& ~(u64
)(pte_size
- 1),
2540 new = (const void *)&gentry
;
2546 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
2548 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
2549 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
2553 kvm_mmu_audit(vcpu
, "post pte write");
2554 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2555 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
2556 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
2557 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2561 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
2566 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
2568 spin_lock(&vcpu
->kvm
->mmu_lock
);
2569 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
2570 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2573 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
2575 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
2577 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
2578 struct kvm_mmu_page
*sp
;
2580 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
2581 struct kvm_mmu_page
, link
);
2582 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2583 ++vcpu
->kvm
->stat
.mmu_recycled
;
2587 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
2590 enum emulation_result er
;
2592 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
2601 r
= mmu_topup_memory_caches(vcpu
);
2605 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
2610 case EMULATE_DO_MMIO
:
2611 ++vcpu
->stat
.mmio_exits
;
2614 kvm_report_emulation_failure(vcpu
, "pagetable");
2622 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
2624 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
2626 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
2627 kvm_mmu_flush_tlb(vcpu
);
2628 ++vcpu
->stat
.invlpg
;
2630 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
2632 void kvm_enable_tdp(void)
2636 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
2638 void kvm_disable_tdp(void)
2640 tdp_enabled
= false;
2642 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
2644 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
2646 struct kvm_mmu_page
*sp
;
2648 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
2649 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
2650 struct kvm_mmu_page
, link
);
2651 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2654 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
2657 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
2664 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
2665 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2666 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
2668 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2669 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
2671 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2672 * Therefore we need to allocate shadow page tables in the first
2673 * 4GB of memory, which happens to fit the DMA32 zone.
2675 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
2678 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
2679 for (i
= 0; i
< 4; ++i
)
2680 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2685 free_mmu_pages(vcpu
);
2689 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
2692 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2694 return alloc_mmu_pages(vcpu
);
2697 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
2700 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2702 return init_kvm_mmu(vcpu
);
2705 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
2709 destroy_kvm_mmu(vcpu
);
2710 free_mmu_pages(vcpu
);
2711 mmu_free_memory_caches(vcpu
);
2714 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
2716 struct kvm_mmu_page
*sp
;
2718 spin_lock(&kvm
->mmu_lock
);
2719 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
2723 if (!test_bit(slot
, sp
->slot_bitmap
))
2727 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
2729 if (pt
[i
] & PT_WRITABLE_MASK
)
2730 pt
[i
] &= ~PT_WRITABLE_MASK
;
2732 kvm_flush_remote_tlbs(kvm
);
2733 spin_unlock(&kvm
->mmu_lock
);
2736 void kvm_mmu_zap_all(struct kvm
*kvm
)
2738 struct kvm_mmu_page
*sp
, *node
;
2740 spin_lock(&kvm
->mmu_lock
);
2741 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
2742 if (kvm_mmu_zap_page(kvm
, sp
))
2743 node
= container_of(kvm
->arch
.active_mmu_pages
.next
,
2744 struct kvm_mmu_page
, link
);
2745 spin_unlock(&kvm
->mmu_lock
);
2747 kvm_flush_remote_tlbs(kvm
);
2750 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
2752 struct kvm_mmu_page
*page
;
2754 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
2755 struct kvm_mmu_page
, link
);
2756 kvm_mmu_zap_page(kvm
, page
);
2759 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
2762 struct kvm
*kvm_freed
= NULL
;
2763 int cache_count
= 0;
2765 spin_lock(&kvm_lock
);
2767 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
2770 if (!down_read_trylock(&kvm
->slots_lock
))
2772 spin_lock(&kvm
->mmu_lock
);
2773 npages
= kvm
->arch
.n_alloc_mmu_pages
-
2774 kvm
->arch
.n_free_mmu_pages
;
2775 cache_count
+= npages
;
2776 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
2777 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
2783 spin_unlock(&kvm
->mmu_lock
);
2784 up_read(&kvm
->slots_lock
);
2787 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
2789 spin_unlock(&kvm_lock
);
2794 static struct shrinker mmu_shrinker
= {
2795 .shrink
= mmu_shrink
,
2796 .seeks
= DEFAULT_SEEKS
* 10,
2799 static void mmu_destroy_caches(void)
2801 if (pte_chain_cache
)
2802 kmem_cache_destroy(pte_chain_cache
);
2803 if (rmap_desc_cache
)
2804 kmem_cache_destroy(rmap_desc_cache
);
2805 if (mmu_page_header_cache
)
2806 kmem_cache_destroy(mmu_page_header_cache
);
2809 void kvm_mmu_module_exit(void)
2811 mmu_destroy_caches();
2812 unregister_shrinker(&mmu_shrinker
);
2815 int kvm_mmu_module_init(void)
2817 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2818 sizeof(struct kvm_pte_chain
),
2820 if (!pte_chain_cache
)
2822 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2823 sizeof(struct kvm_rmap_desc
),
2825 if (!rmap_desc_cache
)
2828 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2829 sizeof(struct kvm_mmu_page
),
2831 if (!mmu_page_header_cache
)
2834 register_shrinker(&mmu_shrinker
);
2839 mmu_destroy_caches();
2844 * Caculate mmu pages needed for kvm.
2846 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2849 unsigned int nr_mmu_pages
;
2850 unsigned int nr_pages
= 0;
2852 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2853 nr_pages
+= kvm
->memslots
[i
].npages
;
2855 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2856 nr_mmu_pages
= max(nr_mmu_pages
,
2857 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2859 return nr_mmu_pages
;
2862 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2865 if (len
> buffer
->len
)
2870 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2875 ret
= pv_mmu_peek_buffer(buffer
, len
);
2880 buffer
->processed
+= len
;
2884 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2885 gpa_t addr
, gpa_t value
)
2890 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2893 r
= mmu_topup_memory_caches(vcpu
);
2897 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2903 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2905 kvm_x86_ops
->tlb_flush(vcpu
);
2906 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
2910 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2912 spin_lock(&vcpu
->kvm
->mmu_lock
);
2913 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2914 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2918 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2919 struct kvm_pv_mmu_op_buffer
*buffer
)
2921 struct kvm_mmu_op_header
*header
;
2923 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2926 switch (header
->op
) {
2927 case KVM_MMU_OP_WRITE_PTE
: {
2928 struct kvm_mmu_op_write_pte
*wpte
;
2930 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2933 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2936 case KVM_MMU_OP_FLUSH_TLB
: {
2937 struct kvm_mmu_op_flush_tlb
*ftlb
;
2939 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2942 return kvm_pv_mmu_flush_tlb(vcpu
);
2944 case KVM_MMU_OP_RELEASE_PT
: {
2945 struct kvm_mmu_op_release_pt
*rpt
;
2947 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2950 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2956 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2957 gpa_t addr
, unsigned long *ret
)
2960 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
2962 buffer
->ptr
= buffer
->buf
;
2963 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
2964 buffer
->processed
= 0;
2966 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
2970 while (buffer
->len
) {
2971 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
2980 *ret
= buffer
->processed
;
2986 static const char *audit_msg
;
2988 static gva_t
canonicalize(gva_t gva
)
2990 #ifdef CONFIG_X86_64
2991 gva
= (long long)(gva
<< 16) >> 16;
2996 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2997 gva_t va
, int level
)
2999 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
3001 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
3003 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
3006 if (ent
== shadow_trap_nonpresent_pte
)
3009 va
= canonicalize(va
);
3011 if (ent
== shadow_notrap_nonpresent_pte
)
3012 printk(KERN_ERR
"audit: (%s) nontrapping pte"
3013 " in nonleaf level: levels %d gva %lx"
3014 " level %d pte %llx\n", audit_msg
,
3015 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
3017 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
3019 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
3020 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
3022 if (is_shadow_present_pte(ent
)
3023 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
3024 printk(KERN_ERR
"xx audit error: (%s) levels %d"
3025 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
3026 audit_msg
, vcpu
->arch
.mmu
.root_level
,
3028 is_shadow_present_pte(ent
));
3029 else if (ent
== shadow_notrap_nonpresent_pte
3030 && !is_error_hpa(hpa
))
3031 printk(KERN_ERR
"audit: (%s) notrap shadow,"
3032 " valid guest gva %lx\n", audit_msg
, va
);
3033 kvm_release_pfn_clean(pfn
);
3039 static void audit_mappings(struct kvm_vcpu
*vcpu
)
3043 if (vcpu
->arch
.mmu
.root_level
== 4)
3044 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
3046 for (i
= 0; i
< 4; ++i
)
3047 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
3048 audit_mappings_page(vcpu
,
3049 vcpu
->arch
.mmu
.pae_root
[i
],
3054 static int count_rmaps(struct kvm_vcpu
*vcpu
)
3059 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
3060 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
3061 struct kvm_rmap_desc
*d
;
3063 for (j
= 0; j
< m
->npages
; ++j
) {
3064 unsigned long *rmapp
= &m
->rmap
[j
];
3068 if (!(*rmapp
& 1)) {
3072 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
3074 for (k
= 0; k
< RMAP_EXT
; ++k
)
3075 if (d
->shadow_ptes
[k
])
3086 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
3089 struct kvm_mmu_page
*sp
;
3092 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3095 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
3098 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3101 if (!(ent
& PT_PRESENT_MASK
))
3103 if (!(ent
& PT_WRITABLE_MASK
))
3111 static void audit_rmap(struct kvm_vcpu
*vcpu
)
3113 int n_rmap
= count_rmaps(vcpu
);
3114 int n_actual
= count_writable_mappings(vcpu
);
3116 if (n_rmap
!= n_actual
)
3117 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
3118 __func__
, audit_msg
, n_rmap
, n_actual
);
3121 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
3123 struct kvm_mmu_page
*sp
;
3124 struct kvm_memory_slot
*slot
;
3125 unsigned long *rmapp
;
3128 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3129 if (sp
->role
.metaphysical
)
3132 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
3133 slot
= gfn_to_memslot_unaliased(vcpu
->kvm
, sp
->gfn
);
3134 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
3136 printk(KERN_ERR
"%s: (%s) shadow page has writable"
3137 " mappings: gfn %lx role %x\n",
3138 __func__
, audit_msg
, sp
->gfn
,
3143 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
3150 audit_write_protection(vcpu
);
3151 audit_mappings(vcpu
);