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
];
358 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
360 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
361 sizeof(struct kvm_pte_chain
));
364 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
369 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
371 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
372 sizeof(struct kvm_rmap_desc
));
375 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
381 * Return the pointer to the largepage write count for a given
382 * gfn, handling slots that are not large page aligned.
384 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
388 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
389 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
390 return &slot
->lpage_info
[idx
].write_count
;
393 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
397 gfn
= unalias_gfn(kvm
, gfn
);
398 write_count
= slot_largepage_idx(gfn
,
399 gfn_to_memslot_unaliased(kvm
, gfn
));
403 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
407 gfn
= unalias_gfn(kvm
, gfn
);
408 write_count
= slot_largepage_idx(gfn
,
409 gfn_to_memslot_unaliased(kvm
, gfn
));
411 WARN_ON(*write_count
< 0);
414 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
416 struct kvm_memory_slot
*slot
;
419 gfn
= unalias_gfn(kvm
, gfn
);
420 slot
= gfn_to_memslot_unaliased(kvm
, gfn
);
422 largepage_idx
= slot_largepage_idx(gfn
, slot
);
423 return *largepage_idx
;
429 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
431 struct vm_area_struct
*vma
;
435 addr
= gfn_to_hva(kvm
, gfn
);
436 if (kvm_is_error_hva(addr
))
439 down_read(¤t
->mm
->mmap_sem
);
440 vma
= find_vma(current
->mm
, addr
);
441 if (vma
&& is_vm_hugetlb_page(vma
))
443 up_read(¤t
->mm
->mmap_sem
);
448 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
450 struct kvm_memory_slot
*slot
;
452 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
455 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
458 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
459 if (slot
&& slot
->dirty_bitmap
)
466 * Take gfn and return the reverse mapping to it.
467 * Note: gfn must be unaliased before this function get called
470 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
472 struct kvm_memory_slot
*slot
;
475 slot
= gfn_to_memslot(kvm
, gfn
);
477 return &slot
->rmap
[gfn
- slot
->base_gfn
];
479 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
480 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
482 return &slot
->lpage_info
[idx
].rmap_pde
;
486 * Reverse mapping data structures:
488 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
489 * that points to page_address(page).
491 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
492 * containing more mappings.
494 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
496 struct kvm_mmu_page
*sp
;
497 struct kvm_rmap_desc
*desc
;
498 unsigned long *rmapp
;
501 if (!is_rmap_pte(*spte
))
503 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
504 sp
= page_header(__pa(spte
));
505 sp
->gfns
[spte
- sp
->spt
] = gfn
;
506 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
508 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
509 *rmapp
= (unsigned long)spte
;
510 } else if (!(*rmapp
& 1)) {
511 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
512 desc
= mmu_alloc_rmap_desc(vcpu
);
513 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
514 desc
->shadow_ptes
[1] = spte
;
515 *rmapp
= (unsigned long)desc
| 1;
517 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
518 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
519 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
521 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
522 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
525 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
527 desc
->shadow_ptes
[i
] = spte
;
531 static void rmap_desc_remove_entry(unsigned long *rmapp
,
532 struct kvm_rmap_desc
*desc
,
534 struct kvm_rmap_desc
*prev_desc
)
538 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
540 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
541 desc
->shadow_ptes
[j
] = NULL
;
544 if (!prev_desc
&& !desc
->more
)
545 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
548 prev_desc
->more
= desc
->more
;
550 *rmapp
= (unsigned long)desc
->more
| 1;
551 mmu_free_rmap_desc(desc
);
554 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
556 struct kvm_rmap_desc
*desc
;
557 struct kvm_rmap_desc
*prev_desc
;
558 struct kvm_mmu_page
*sp
;
560 unsigned long *rmapp
;
563 if (!is_rmap_pte(*spte
))
565 sp
= page_header(__pa(spte
));
566 pfn
= spte_to_pfn(*spte
);
567 if (*spte
& shadow_accessed_mask
)
568 kvm_set_pfn_accessed(pfn
);
569 if (is_writeble_pte(*spte
))
570 kvm_release_pfn_dirty(pfn
);
572 kvm_release_pfn_clean(pfn
);
573 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
575 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
577 } else if (!(*rmapp
& 1)) {
578 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
579 if ((u64
*)*rmapp
!= spte
) {
580 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
586 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
587 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
590 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
591 if (desc
->shadow_ptes
[i
] == spte
) {
592 rmap_desc_remove_entry(rmapp
,
604 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
606 struct kvm_rmap_desc
*desc
;
607 struct kvm_rmap_desc
*prev_desc
;
613 else if (!(*rmapp
& 1)) {
615 return (u64
*)*rmapp
;
618 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
622 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
623 if (prev_spte
== spte
)
624 return desc
->shadow_ptes
[i
];
625 prev_spte
= desc
->shadow_ptes
[i
];
632 static int rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
634 unsigned long *rmapp
;
636 int write_protected
= 0;
638 gfn
= unalias_gfn(kvm
, gfn
);
639 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
641 spte
= rmap_next(kvm
, rmapp
, NULL
);
644 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
645 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
646 if (is_writeble_pte(*spte
)) {
647 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
650 spte
= rmap_next(kvm
, rmapp
, spte
);
652 if (write_protected
) {
655 spte
= rmap_next(kvm
, rmapp
, NULL
);
656 pfn
= spte_to_pfn(*spte
);
657 kvm_set_pfn_dirty(pfn
);
660 /* check for huge page mappings */
661 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
662 spte
= rmap_next(kvm
, rmapp
, NULL
);
665 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
666 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
667 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
668 if (is_writeble_pte(*spte
)) {
669 rmap_remove(kvm
, spte
);
671 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
675 spte
= rmap_next(kvm
, rmapp
, spte
);
678 return write_protected
;
681 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
684 int need_tlb_flush
= 0;
686 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
687 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
688 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
689 rmap_remove(kvm
, spte
);
690 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
693 return need_tlb_flush
;
696 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
697 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
))
703 * If mmap_sem isn't taken, we can look the memslots with only
704 * the mmu_lock by skipping over the slots with userspace_addr == 0.
706 for (i
= 0; i
< kvm
->nmemslots
; i
++) {
707 struct kvm_memory_slot
*memslot
= &kvm
->memslots
[i
];
708 unsigned long start
= memslot
->userspace_addr
;
711 /* mmu_lock protects userspace_addr */
715 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
716 if (hva
>= start
&& hva
< end
) {
717 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
718 retval
|= handler(kvm
, &memslot
->rmap
[gfn_offset
]);
719 retval
|= handler(kvm
,
720 &memslot
->lpage_info
[
722 KVM_PAGES_PER_HPAGE
].rmap_pde
);
729 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
731 return kvm_handle_hva(kvm
, hva
, kvm_unmap_rmapp
);
734 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
739 /* always return old for EPT */
740 if (!shadow_accessed_mask
)
743 spte
= rmap_next(kvm
, rmapp
, NULL
);
747 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
748 _young
= _spte
& PT_ACCESSED_MASK
;
751 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
753 spte
= rmap_next(kvm
, rmapp
, spte
);
758 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
760 return kvm_handle_hva(kvm
, hva
, kvm_age_rmapp
);
764 static int is_empty_shadow_page(u64
*spt
)
769 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
770 if (is_shadow_present_pte(*pos
)) {
771 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
779 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
781 ASSERT(is_empty_shadow_page(sp
->spt
));
783 __free_page(virt_to_page(sp
->spt
));
784 __free_page(virt_to_page(sp
->gfns
));
786 ++kvm
->arch
.n_free_mmu_pages
;
789 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
791 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
794 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
797 struct kvm_mmu_page
*sp
;
799 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
800 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
801 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
802 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
803 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
804 INIT_LIST_HEAD(&sp
->oos_link
);
805 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
807 sp
->parent_pte
= parent_pte
;
808 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
812 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
813 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
815 struct kvm_pte_chain
*pte_chain
;
816 struct hlist_node
*node
;
821 if (!sp
->multimapped
) {
822 u64
*old
= sp
->parent_pte
;
825 sp
->parent_pte
= parent_pte
;
829 pte_chain
= mmu_alloc_pte_chain(vcpu
);
830 INIT_HLIST_HEAD(&sp
->parent_ptes
);
831 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
832 pte_chain
->parent_ptes
[0] = old
;
834 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
835 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
837 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
838 if (!pte_chain
->parent_ptes
[i
]) {
839 pte_chain
->parent_ptes
[i
] = parent_pte
;
843 pte_chain
= mmu_alloc_pte_chain(vcpu
);
845 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
846 pte_chain
->parent_ptes
[0] = parent_pte
;
849 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
852 struct kvm_pte_chain
*pte_chain
;
853 struct hlist_node
*node
;
856 if (!sp
->multimapped
) {
857 BUG_ON(sp
->parent_pte
!= parent_pte
);
858 sp
->parent_pte
= NULL
;
861 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
862 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
863 if (!pte_chain
->parent_ptes
[i
])
865 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
867 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
868 && pte_chain
->parent_ptes
[i
+ 1]) {
869 pte_chain
->parent_ptes
[i
]
870 = pte_chain
->parent_ptes
[i
+ 1];
873 pte_chain
->parent_ptes
[i
] = NULL
;
875 hlist_del(&pte_chain
->link
);
876 mmu_free_pte_chain(pte_chain
);
877 if (hlist_empty(&sp
->parent_ptes
)) {
879 sp
->parent_pte
= NULL
;
888 static void mmu_parent_walk(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
889 mmu_parent_walk_fn fn
)
891 struct kvm_pte_chain
*pte_chain
;
892 struct hlist_node
*node
;
893 struct kvm_mmu_page
*parent_sp
;
896 if (!sp
->multimapped
&& sp
->parent_pte
) {
897 parent_sp
= page_header(__pa(sp
->parent_pte
));
899 mmu_parent_walk(vcpu
, parent_sp
, fn
);
902 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
903 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
904 if (!pte_chain
->parent_ptes
[i
])
906 parent_sp
= page_header(__pa(pte_chain
->parent_ptes
[i
]));
908 mmu_parent_walk(vcpu
, parent_sp
, fn
);
912 static void kvm_mmu_update_unsync_bitmap(u64
*spte
)
915 struct kvm_mmu_page
*sp
= page_header(__pa(spte
));
917 index
= spte
- sp
->spt
;
918 if (!__test_and_set_bit(index
, sp
->unsync_child_bitmap
))
919 sp
->unsync_children
++;
920 WARN_ON(!sp
->unsync_children
);
923 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page
*sp
)
925 struct kvm_pte_chain
*pte_chain
;
926 struct hlist_node
*node
;
932 if (!sp
->multimapped
) {
933 kvm_mmu_update_unsync_bitmap(sp
->parent_pte
);
937 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
938 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
939 if (!pte_chain
->parent_ptes
[i
])
941 kvm_mmu_update_unsync_bitmap(pte_chain
->parent_ptes
[i
]);
945 static int unsync_walk_fn(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
947 kvm_mmu_update_parents_unsync(sp
);
951 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu
*vcpu
,
952 struct kvm_mmu_page
*sp
)
954 mmu_parent_walk(vcpu
, sp
, unsync_walk_fn
);
955 kvm_mmu_update_parents_unsync(sp
);
958 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
959 struct kvm_mmu_page
*sp
)
963 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
964 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
967 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
968 struct kvm_mmu_page
*sp
)
973 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
977 #define KVM_PAGE_ARRAY_NR 16
979 struct kvm_mmu_pages
{
980 struct mmu_page_and_offset
{
981 struct kvm_mmu_page
*sp
;
983 } page
[KVM_PAGE_ARRAY_NR
];
987 #define for_each_unsync_children(bitmap, idx) \
988 for (idx = find_first_bit(bitmap, 512); \
990 idx = find_next_bit(bitmap, 512, idx+1))
992 static int mmu_pages_add(struct kvm_mmu_pages
*pvec
, struct kvm_mmu_page
*sp
,
998 for (i
=0; i
< pvec
->nr
; i
++)
999 if (pvec
->page
[i
].sp
== sp
)
1002 pvec
->page
[pvec
->nr
].sp
= sp
;
1003 pvec
->page
[pvec
->nr
].idx
= idx
;
1005 return (pvec
->nr
== KVM_PAGE_ARRAY_NR
);
1008 static int __mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1009 struct kvm_mmu_pages
*pvec
)
1011 int i
, ret
, nr_unsync_leaf
= 0;
1013 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
1014 u64 ent
= sp
->spt
[i
];
1016 if (is_shadow_present_pte(ent
) && !is_large_pte(ent
)) {
1017 struct kvm_mmu_page
*child
;
1018 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
1020 if (child
->unsync_children
) {
1021 if (mmu_pages_add(pvec
, child
, i
))
1024 ret
= __mmu_unsync_walk(child
, pvec
);
1026 __clear_bit(i
, sp
->unsync_child_bitmap
);
1028 nr_unsync_leaf
+= ret
;
1033 if (child
->unsync
) {
1035 if (mmu_pages_add(pvec
, child
, i
))
1041 if (find_first_bit(sp
->unsync_child_bitmap
, 512) == 512)
1042 sp
->unsync_children
= 0;
1044 return nr_unsync_leaf
;
1047 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1048 struct kvm_mmu_pages
*pvec
)
1050 if (!sp
->unsync_children
)
1053 mmu_pages_add(pvec
, sp
, 0);
1054 return __mmu_unsync_walk(sp
, pvec
);
1057 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
1060 struct hlist_head
*bucket
;
1061 struct kvm_mmu_page
*sp
;
1062 struct hlist_node
*node
;
1064 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1065 index
= kvm_page_table_hashfn(gfn
);
1066 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1067 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
1068 if (sp
->gfn
== gfn
&& !sp
->role
.direct
1069 && !sp
->role
.invalid
) {
1070 pgprintk("%s: found role %x\n",
1071 __func__
, sp
->role
.word
);
1077 static void kvm_unlink_unsync_global(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1079 list_del(&sp
->oos_link
);
1080 --kvm
->stat
.mmu_unsync_global
;
1083 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1085 WARN_ON(!sp
->unsync
);
1088 kvm_unlink_unsync_global(kvm
, sp
);
1089 --kvm
->stat
.mmu_unsync
;
1092 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
);
1094 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1096 if (sp
->role
.glevels
!= vcpu
->arch
.mmu
.root_level
) {
1097 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1101 if (rmap_write_protect(vcpu
->kvm
, sp
->gfn
))
1102 kvm_flush_remote_tlbs(vcpu
->kvm
);
1103 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1104 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1105 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1109 kvm_mmu_flush_tlb(vcpu
);
1113 struct mmu_page_path
{
1114 struct kvm_mmu_page
*parent
[PT64_ROOT_LEVEL
-1];
1115 unsigned int idx
[PT64_ROOT_LEVEL
-1];
1118 #define for_each_sp(pvec, sp, parents, i) \
1119 for (i = mmu_pages_next(&pvec, &parents, -1), \
1120 sp = pvec.page[i].sp; \
1121 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1122 i = mmu_pages_next(&pvec, &parents, i))
1124 static int mmu_pages_next(struct kvm_mmu_pages
*pvec
,
1125 struct mmu_page_path
*parents
,
1130 for (n
= i
+1; n
< pvec
->nr
; n
++) {
1131 struct kvm_mmu_page
*sp
= pvec
->page
[n
].sp
;
1133 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1134 parents
->idx
[0] = pvec
->page
[n
].idx
;
1138 parents
->parent
[sp
->role
.level
-2] = sp
;
1139 parents
->idx
[sp
->role
.level
-1] = pvec
->page
[n
].idx
;
1145 static void mmu_pages_clear_parents(struct mmu_page_path
*parents
)
1147 struct kvm_mmu_page
*sp
;
1148 unsigned int level
= 0;
1151 unsigned int idx
= parents
->idx
[level
];
1153 sp
= parents
->parent
[level
];
1157 --sp
->unsync_children
;
1158 WARN_ON((int)sp
->unsync_children
< 0);
1159 __clear_bit(idx
, sp
->unsync_child_bitmap
);
1161 } while (level
< PT64_ROOT_LEVEL
-1 && !sp
->unsync_children
);
1164 static void kvm_mmu_pages_init(struct kvm_mmu_page
*parent
,
1165 struct mmu_page_path
*parents
,
1166 struct kvm_mmu_pages
*pvec
)
1168 parents
->parent
[parent
->role
.level
-1] = NULL
;
1172 static void mmu_sync_children(struct kvm_vcpu
*vcpu
,
1173 struct kvm_mmu_page
*parent
)
1176 struct kvm_mmu_page
*sp
;
1177 struct mmu_page_path parents
;
1178 struct kvm_mmu_pages pages
;
1180 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1181 while (mmu_unsync_walk(parent
, &pages
)) {
1184 for_each_sp(pages
, sp
, parents
, i
)
1185 protected |= rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1188 kvm_flush_remote_tlbs(vcpu
->kvm
);
1190 for_each_sp(pages
, sp
, parents
, i
) {
1191 kvm_sync_page(vcpu
, sp
);
1192 mmu_pages_clear_parents(&parents
);
1194 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1195 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1199 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1207 union kvm_mmu_page_role role
;
1210 struct hlist_head
*bucket
;
1211 struct kvm_mmu_page
*sp
;
1212 struct hlist_node
*node
, *tmp
;
1214 role
= vcpu
->arch
.mmu
.base_role
;
1216 role
.direct
= direct
;
1217 role
.access
= access
;
1218 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1219 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1220 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1221 role
.quadrant
= quadrant
;
1223 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
1225 index
= kvm_page_table_hashfn(gfn
);
1226 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1227 hlist_for_each_entry_safe(sp
, node
, tmp
, bucket
, hash_link
)
1228 if (sp
->gfn
== gfn
) {
1230 if (kvm_sync_page(vcpu
, sp
))
1233 if (sp
->role
.word
!= role
.word
)
1236 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1237 if (sp
->unsync_children
) {
1238 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
1239 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1241 pgprintk("%s: found\n", __func__
);
1244 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1245 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
1248 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
1251 sp
->global
= role
.cr4_pge
;
1252 hlist_add_head(&sp
->hash_link
, bucket
);
1254 if (rmap_write_protect(vcpu
->kvm
, gfn
))
1255 kvm_flush_remote_tlbs(vcpu
->kvm
);
1256 account_shadowed(vcpu
->kvm
, gfn
);
1258 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1259 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1261 nonpaging_prefetch_page(vcpu
, sp
);
1265 static void shadow_walk_init(struct kvm_shadow_walk_iterator
*iterator
,
1266 struct kvm_vcpu
*vcpu
, u64 addr
)
1268 iterator
->addr
= addr
;
1269 iterator
->shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1270 iterator
->level
= vcpu
->arch
.mmu
.shadow_root_level
;
1271 if (iterator
->level
== PT32E_ROOT_LEVEL
) {
1272 iterator
->shadow_addr
1273 = vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1274 iterator
->shadow_addr
&= PT64_BASE_ADDR_MASK
;
1276 if (!iterator
->shadow_addr
)
1277 iterator
->level
= 0;
1281 static bool shadow_walk_okay(struct kvm_shadow_walk_iterator
*iterator
)
1283 if (iterator
->level
< PT_PAGE_TABLE_LEVEL
)
1285 iterator
->index
= SHADOW_PT_INDEX(iterator
->addr
, iterator
->level
);
1286 iterator
->sptep
= ((u64
*)__va(iterator
->shadow_addr
)) + iterator
->index
;
1290 static void shadow_walk_next(struct kvm_shadow_walk_iterator
*iterator
)
1292 iterator
->shadow_addr
= *iterator
->sptep
& PT64_BASE_ADDR_MASK
;
1296 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1297 struct kvm_mmu_page
*sp
)
1305 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1306 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1307 if (is_shadow_present_pte(pt
[i
]))
1308 rmap_remove(kvm
, &pt
[i
]);
1309 pt
[i
] = shadow_trap_nonpresent_pte
;
1314 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1317 if (is_shadow_present_pte(ent
)) {
1318 if (!is_large_pte(ent
)) {
1319 ent
&= PT64_BASE_ADDR_MASK
;
1320 mmu_page_remove_parent_pte(page_header(ent
),
1324 rmap_remove(kvm
, &pt
[i
]);
1327 pt
[i
] = shadow_trap_nonpresent_pte
;
1331 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1333 mmu_page_remove_parent_pte(sp
, parent_pte
);
1336 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1340 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
1342 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
1345 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1349 while (sp
->multimapped
|| sp
->parent_pte
) {
1350 if (!sp
->multimapped
)
1351 parent_pte
= sp
->parent_pte
;
1353 struct kvm_pte_chain
*chain
;
1355 chain
= container_of(sp
->parent_ptes
.first
,
1356 struct kvm_pte_chain
, link
);
1357 parent_pte
= chain
->parent_ptes
[0];
1359 BUG_ON(!parent_pte
);
1360 kvm_mmu_put_page(sp
, parent_pte
);
1361 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
1365 static int mmu_zap_unsync_children(struct kvm
*kvm
,
1366 struct kvm_mmu_page
*parent
)
1369 struct mmu_page_path parents
;
1370 struct kvm_mmu_pages pages
;
1372 if (parent
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1375 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1376 while (mmu_unsync_walk(parent
, &pages
)) {
1377 struct kvm_mmu_page
*sp
;
1379 for_each_sp(pages
, sp
, parents
, i
) {
1380 kvm_mmu_zap_page(kvm
, sp
);
1381 mmu_pages_clear_parents(&parents
);
1384 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1390 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1393 ++kvm
->stat
.mmu_shadow_zapped
;
1394 ret
= mmu_zap_unsync_children(kvm
, sp
);
1395 kvm_mmu_page_unlink_children(kvm
, sp
);
1396 kvm_mmu_unlink_parents(kvm
, sp
);
1397 kvm_flush_remote_tlbs(kvm
);
1398 if (!sp
->role
.invalid
&& !sp
->role
.direct
)
1399 unaccount_shadowed(kvm
, sp
->gfn
);
1401 kvm_unlink_unsync_page(kvm
, sp
);
1402 if (!sp
->root_count
) {
1403 hlist_del(&sp
->hash_link
);
1404 kvm_mmu_free_page(kvm
, sp
);
1406 sp
->role
.invalid
= 1;
1407 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1408 kvm_reload_remote_mmus(kvm
);
1410 kvm_mmu_reset_last_pte_updated(kvm
);
1415 * Changing the number of mmu pages allocated to the vm
1416 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1418 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
1421 * If we set the number of mmu pages to be smaller be than the
1422 * number of actived pages , we must to free some mmu pages before we
1426 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
1428 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
1429 - kvm
->arch
.n_free_mmu_pages
;
1431 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
1432 struct kvm_mmu_page
*page
;
1434 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1435 struct kvm_mmu_page
, link
);
1436 kvm_mmu_zap_page(kvm
, page
);
1439 kvm
->arch
.n_free_mmu_pages
= 0;
1442 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
1443 - kvm
->arch
.n_alloc_mmu_pages
;
1445 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
1448 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1451 struct hlist_head
*bucket
;
1452 struct kvm_mmu_page
*sp
;
1453 struct hlist_node
*node
, *n
;
1456 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1458 index
= kvm_page_table_hashfn(gfn
);
1459 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1460 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
1461 if (sp
->gfn
== gfn
&& !sp
->role
.direct
) {
1462 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
1465 if (kvm_mmu_zap_page(kvm
, sp
))
1471 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1474 struct hlist_head
*bucket
;
1475 struct kvm_mmu_page
*sp
;
1476 struct hlist_node
*node
, *nn
;
1478 index
= kvm_page_table_hashfn(gfn
);
1479 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1480 hlist_for_each_entry_safe(sp
, node
, nn
, bucket
, hash_link
) {
1481 if (sp
->gfn
== gfn
&& !sp
->role
.direct
1482 && !sp
->role
.invalid
) {
1483 pgprintk("%s: zap %lx %x\n",
1484 __func__
, gfn
, sp
->role
.word
);
1485 kvm_mmu_zap_page(kvm
, sp
);
1490 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1492 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1493 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1495 __set_bit(slot
, sp
->slot_bitmap
);
1498 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1503 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1506 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1507 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1508 set_shadow_pte(&pt
[i
], shadow_trap_nonpresent_pte
);
1512 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1516 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1518 if (gpa
== UNMAPPED_GVA
)
1521 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1527 * The function is based on mtrr_type_lookup() in
1528 * arch/x86/kernel/cpu/mtrr/generic.c
1530 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1535 u8 prev_match
, curr_match
;
1536 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1538 if (!mtrr_state
->enabled
)
1541 /* Make end inclusive end, instead of exclusive */
1544 /* Look in fixed ranges. Just return the type as per start */
1545 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1548 if (start
< 0x80000) {
1550 idx
+= (start
>> 16);
1551 return mtrr_state
->fixed_ranges
[idx
];
1552 } else if (start
< 0xC0000) {
1554 idx
+= ((start
- 0x80000) >> 14);
1555 return mtrr_state
->fixed_ranges
[idx
];
1556 } else if (start
< 0x1000000) {
1558 idx
+= ((start
- 0xC0000) >> 12);
1559 return mtrr_state
->fixed_ranges
[idx
];
1564 * Look in variable ranges
1565 * Look of multiple ranges matching this address and pick type
1566 * as per MTRR precedence
1568 if (!(mtrr_state
->enabled
& 2))
1569 return mtrr_state
->def_type
;
1572 for (i
= 0; i
< num_var_ranges
; ++i
) {
1573 unsigned short start_state
, end_state
;
1575 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1578 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1579 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1580 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1581 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1583 start_state
= ((start
& mask
) == (base
& mask
));
1584 end_state
= ((end
& mask
) == (base
& mask
));
1585 if (start_state
!= end_state
)
1588 if ((start
& mask
) != (base
& mask
))
1591 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1592 if (prev_match
== 0xFF) {
1593 prev_match
= curr_match
;
1597 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1598 curr_match
== MTRR_TYPE_UNCACHABLE
)
1599 return MTRR_TYPE_UNCACHABLE
;
1601 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1602 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1603 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1604 curr_match
== MTRR_TYPE_WRBACK
)) {
1605 prev_match
= MTRR_TYPE_WRTHROUGH
;
1606 curr_match
= MTRR_TYPE_WRTHROUGH
;
1609 if (prev_match
!= curr_match
)
1610 return MTRR_TYPE_UNCACHABLE
;
1613 if (prev_match
!= 0xFF)
1616 return mtrr_state
->def_type
;
1619 static u8
get_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1623 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1624 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1625 if (mtrr
== 0xfe || mtrr
== 0xff)
1626 mtrr
= MTRR_TYPE_WRBACK
;
1630 static int kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1633 struct hlist_head
*bucket
;
1634 struct kvm_mmu_page
*s
;
1635 struct hlist_node
*node
, *n
;
1637 index
= kvm_page_table_hashfn(sp
->gfn
);
1638 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1639 /* don't unsync if pagetable is shadowed with multiple roles */
1640 hlist_for_each_entry_safe(s
, node
, n
, bucket
, hash_link
) {
1641 if (s
->gfn
!= sp
->gfn
|| s
->role
.direct
)
1643 if (s
->role
.word
!= sp
->role
.word
)
1646 ++vcpu
->kvm
->stat
.mmu_unsync
;
1650 list_add(&sp
->oos_link
, &vcpu
->kvm
->arch
.oos_global_pages
);
1651 ++vcpu
->kvm
->stat
.mmu_unsync_global
;
1653 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1655 mmu_convert_notrap(sp
);
1659 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1662 struct kvm_mmu_page
*shadow
;
1664 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1666 if (shadow
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1670 if (can_unsync
&& oos_shadow
)
1671 return kvm_unsync_page(vcpu
, shadow
);
1677 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1678 unsigned pte_access
, int user_fault
,
1679 int write_fault
, int dirty
, int largepage
,
1680 int global
, gfn_t gfn
, pfn_t pfn
, bool speculative
,
1685 u64 mt_mask
= shadow_mt_mask
;
1686 struct kvm_mmu_page
*sp
= page_header(__pa(shadow_pte
));
1688 if (!global
&& sp
->global
) {
1691 kvm_unlink_unsync_global(vcpu
->kvm
, sp
);
1692 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
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 if (!kvm_is_mmio_pfn(pfn
)) {
1716 mt_mask
= get_memory_type(vcpu
, gfn
) <<
1717 kvm_x86_ops
->get_mt_mask_shift();
1718 mt_mask
|= VMX_EPT_IGMT_BIT
;
1720 mt_mask
= MTRR_TYPE_UNCACHABLE
<<
1721 kvm_x86_ops
->get_mt_mask_shift();
1725 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1727 if ((pte_access
& ACC_WRITE_MASK
)
1728 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1730 if (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
)) {
1732 spte
= shadow_trap_nonpresent_pte
;
1736 spte
|= PT_WRITABLE_MASK
;
1739 * Optimization: for pte sync, if spte was writable the hash
1740 * lookup is unnecessary (and expensive). Write protection
1741 * is responsibility of mmu_get_page / kvm_sync_page.
1742 * Same reasoning can be applied to dirty page accounting.
1744 if (!can_unsync
&& is_writeble_pte(*shadow_pte
))
1747 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1748 pgprintk("%s: found shadow page for %lx, marking ro\n",
1751 pte_access
&= ~ACC_WRITE_MASK
;
1752 if (is_writeble_pte(spte
))
1753 spte
&= ~PT_WRITABLE_MASK
;
1757 if (pte_access
& ACC_WRITE_MASK
)
1758 mark_page_dirty(vcpu
->kvm
, gfn
);
1761 set_shadow_pte(shadow_pte
, spte
);
1765 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1766 unsigned pt_access
, unsigned pte_access
,
1767 int user_fault
, int write_fault
, int dirty
,
1768 int *ptwrite
, int largepage
, int global
,
1769 gfn_t gfn
, pfn_t pfn
, bool speculative
)
1771 int was_rmapped
= 0;
1772 int was_writeble
= is_writeble_pte(*shadow_pte
);
1774 pgprintk("%s: spte %llx access %x write_fault %d"
1775 " user_fault %d gfn %lx\n",
1776 __func__
, *shadow_pte
, pt_access
,
1777 write_fault
, user_fault
, gfn
);
1779 if (is_rmap_pte(*shadow_pte
)) {
1781 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1782 * the parent of the now unreachable PTE.
1784 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1785 struct kvm_mmu_page
*child
;
1786 u64 pte
= *shadow_pte
;
1788 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1789 mmu_page_remove_parent_pte(child
, shadow_pte
);
1790 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1791 pgprintk("hfn old %lx new %lx\n",
1792 spte_to_pfn(*shadow_pte
), pfn
);
1793 rmap_remove(vcpu
->kvm
, shadow_pte
);
1797 if (set_spte(vcpu
, shadow_pte
, pte_access
, user_fault
, write_fault
,
1798 dirty
, largepage
, global
, gfn
, pfn
, speculative
, true)) {
1801 kvm_x86_ops
->tlb_flush(vcpu
);
1804 pgprintk("%s: setting spte %llx\n", __func__
, *shadow_pte
);
1805 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1806 is_large_pte(*shadow_pte
)? "2MB" : "4kB",
1807 is_present_pte(*shadow_pte
)?"RW":"R", gfn
,
1808 *shadow_pte
, shadow_pte
);
1809 if (!was_rmapped
&& is_large_pte(*shadow_pte
))
1810 ++vcpu
->kvm
->stat
.lpages
;
1812 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1814 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1815 if (!is_rmap_pte(*shadow_pte
))
1816 kvm_release_pfn_clean(pfn
);
1819 kvm_release_pfn_dirty(pfn
);
1821 kvm_release_pfn_clean(pfn
);
1824 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1825 vcpu
->arch
.last_pte_gfn
= gfn
;
1829 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1833 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1834 int largepage
, gfn_t gfn
, pfn_t pfn
)
1836 struct kvm_shadow_walk_iterator iterator
;
1837 struct kvm_mmu_page
*sp
;
1841 for_each_shadow_entry(vcpu
, (u64
)gfn
<< PAGE_SHIFT
, iterator
) {
1842 if (iterator
.level
== PT_PAGE_TABLE_LEVEL
1843 || (largepage
&& iterator
.level
== PT_DIRECTORY_LEVEL
)) {
1844 mmu_set_spte(vcpu
, iterator
.sptep
, ACC_ALL
, ACC_ALL
,
1845 0, write
, 1, &pt_write
,
1846 largepage
, 0, gfn
, pfn
, false);
1847 ++vcpu
->stat
.pf_fixed
;
1851 if (*iterator
.sptep
== shadow_trap_nonpresent_pte
) {
1852 pseudo_gfn
= (iterator
.addr
& PT64_DIR_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1853 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, iterator
.addr
,
1855 1, ACC_ALL
, iterator
.sptep
);
1857 pgprintk("nonpaging_map: ENOMEM\n");
1858 kvm_release_pfn_clean(pfn
);
1862 set_shadow_pte(iterator
.sptep
,
1864 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1865 | shadow_user_mask
| shadow_x_mask
);
1871 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1876 unsigned long mmu_seq
;
1878 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1879 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1883 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1885 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1888 if (is_error_pfn(pfn
)) {
1889 kvm_release_pfn_clean(pfn
);
1893 spin_lock(&vcpu
->kvm
->mmu_lock
);
1894 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1896 kvm_mmu_free_some_pages(vcpu
);
1897 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
);
1898 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1904 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1905 kvm_release_pfn_clean(pfn
);
1910 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1913 struct kvm_mmu_page
*sp
;
1915 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1917 spin_lock(&vcpu
->kvm
->mmu_lock
);
1918 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1919 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1921 sp
= page_header(root
);
1923 if (!sp
->root_count
&& sp
->role
.invalid
)
1924 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1925 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1926 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1929 for (i
= 0; i
< 4; ++i
) {
1930 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1933 root
&= PT64_BASE_ADDR_MASK
;
1934 sp
= page_header(root
);
1936 if (!sp
->root_count
&& sp
->role
.invalid
)
1937 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1939 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1941 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1942 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1945 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1949 struct kvm_mmu_page
*sp
;
1952 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1954 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1955 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1957 ASSERT(!VALID_PAGE(root
));
1960 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1961 PT64_ROOT_LEVEL
, direct
,
1963 root
= __pa(sp
->spt
);
1965 vcpu
->arch
.mmu
.root_hpa
= root
;
1968 direct
= !is_paging(vcpu
);
1971 for (i
= 0; i
< 4; ++i
) {
1972 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1974 ASSERT(!VALID_PAGE(root
));
1975 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1976 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1977 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1980 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1981 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1983 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1984 PT32_ROOT_LEVEL
, direct
,
1986 root
= __pa(sp
->spt
);
1988 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
1990 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
1993 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
1996 struct kvm_mmu_page
*sp
;
1998 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2000 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2001 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2002 sp
= page_header(root
);
2003 mmu_sync_children(vcpu
, sp
);
2006 for (i
= 0; i
< 4; ++i
) {
2007 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2010 root
&= PT64_BASE_ADDR_MASK
;
2011 sp
= page_header(root
);
2012 mmu_sync_children(vcpu
, sp
);
2017 static void mmu_sync_global(struct kvm_vcpu
*vcpu
)
2019 struct kvm
*kvm
= vcpu
->kvm
;
2020 struct kvm_mmu_page
*sp
, *n
;
2022 list_for_each_entry_safe(sp
, n
, &kvm
->arch
.oos_global_pages
, oos_link
)
2023 kvm_sync_page(vcpu
, sp
);
2026 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2028 spin_lock(&vcpu
->kvm
->mmu_lock
);
2029 mmu_sync_roots(vcpu
);
2030 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2033 void kvm_mmu_sync_global(struct kvm_vcpu
*vcpu
)
2035 spin_lock(&vcpu
->kvm
->mmu_lock
);
2036 mmu_sync_global(vcpu
);
2037 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2040 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
2045 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
2051 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
2052 r
= mmu_topup_memory_caches(vcpu
);
2057 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2059 gfn
= gva
>> PAGE_SHIFT
;
2061 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
2062 error_code
& PFERR_WRITE_MASK
, gfn
);
2065 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
2071 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2072 unsigned long mmu_seq
;
2075 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2077 r
= mmu_topup_memory_caches(vcpu
);
2081 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
2082 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2085 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2087 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2088 if (is_error_pfn(pfn
)) {
2089 kvm_release_pfn_clean(pfn
);
2092 spin_lock(&vcpu
->kvm
->mmu_lock
);
2093 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2095 kvm_mmu_free_some_pages(vcpu
);
2096 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
2097 largepage
, gfn
, pfn
);
2098 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2103 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2104 kvm_release_pfn_clean(pfn
);
2108 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
2110 mmu_free_roots(vcpu
);
2113 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
2115 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2117 context
->new_cr3
= nonpaging_new_cr3
;
2118 context
->page_fault
= nonpaging_page_fault
;
2119 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2120 context
->free
= nonpaging_free
;
2121 context
->prefetch_page
= nonpaging_prefetch_page
;
2122 context
->sync_page
= nonpaging_sync_page
;
2123 context
->invlpg
= nonpaging_invlpg
;
2124 context
->root_level
= 0;
2125 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2126 context
->root_hpa
= INVALID_PAGE
;
2130 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2132 ++vcpu
->stat
.tlb_flush
;
2133 kvm_x86_ops
->tlb_flush(vcpu
);
2136 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2138 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
2139 mmu_free_roots(vcpu
);
2142 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2146 kvm_inject_page_fault(vcpu
, addr
, err_code
);
2149 static void paging_free(struct kvm_vcpu
*vcpu
)
2151 nonpaging_free(vcpu
);
2155 #include "paging_tmpl.h"
2159 #include "paging_tmpl.h"
2162 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
2164 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2166 ASSERT(is_pae(vcpu
));
2167 context
->new_cr3
= paging_new_cr3
;
2168 context
->page_fault
= paging64_page_fault
;
2169 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2170 context
->prefetch_page
= paging64_prefetch_page
;
2171 context
->sync_page
= paging64_sync_page
;
2172 context
->invlpg
= paging64_invlpg
;
2173 context
->free
= paging_free
;
2174 context
->root_level
= level
;
2175 context
->shadow_root_level
= level
;
2176 context
->root_hpa
= INVALID_PAGE
;
2180 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
2182 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
2185 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
2187 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2189 context
->new_cr3
= paging_new_cr3
;
2190 context
->page_fault
= paging32_page_fault
;
2191 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2192 context
->free
= paging_free
;
2193 context
->prefetch_page
= paging32_prefetch_page
;
2194 context
->sync_page
= paging32_sync_page
;
2195 context
->invlpg
= paging32_invlpg
;
2196 context
->root_level
= PT32_ROOT_LEVEL
;
2197 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2198 context
->root_hpa
= INVALID_PAGE
;
2202 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
2204 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
2207 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2209 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2211 context
->new_cr3
= nonpaging_new_cr3
;
2212 context
->page_fault
= tdp_page_fault
;
2213 context
->free
= nonpaging_free
;
2214 context
->prefetch_page
= nonpaging_prefetch_page
;
2215 context
->sync_page
= nonpaging_sync_page
;
2216 context
->invlpg
= nonpaging_invlpg
;
2217 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2218 context
->root_hpa
= INVALID_PAGE
;
2220 if (!is_paging(vcpu
)) {
2221 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2222 context
->root_level
= 0;
2223 } else if (is_long_mode(vcpu
)) {
2224 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2225 context
->root_level
= PT64_ROOT_LEVEL
;
2226 } else if (is_pae(vcpu
)) {
2227 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2228 context
->root_level
= PT32E_ROOT_LEVEL
;
2230 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2231 context
->root_level
= PT32_ROOT_LEVEL
;
2237 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2242 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2244 if (!is_paging(vcpu
))
2245 r
= nonpaging_init_context(vcpu
);
2246 else if (is_long_mode(vcpu
))
2247 r
= paging64_init_context(vcpu
);
2248 else if (is_pae(vcpu
))
2249 r
= paging32E_init_context(vcpu
);
2251 r
= paging32_init_context(vcpu
);
2253 vcpu
->arch
.mmu
.base_role
.glevels
= vcpu
->arch
.mmu
.root_level
;
2258 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
2260 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2263 return init_kvm_tdp_mmu(vcpu
);
2265 return init_kvm_softmmu(vcpu
);
2268 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
2271 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
2272 vcpu
->arch
.mmu
.free(vcpu
);
2273 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2277 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
2279 destroy_kvm_mmu(vcpu
);
2280 return init_kvm_mmu(vcpu
);
2282 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
2284 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
2288 r
= mmu_topup_memory_caches(vcpu
);
2291 spin_lock(&vcpu
->kvm
->mmu_lock
);
2292 kvm_mmu_free_some_pages(vcpu
);
2293 mmu_alloc_roots(vcpu
);
2294 mmu_sync_roots(vcpu
);
2295 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2296 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
2297 kvm_mmu_flush_tlb(vcpu
);
2301 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
2303 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
2305 mmu_free_roots(vcpu
);
2308 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
2309 struct kvm_mmu_page
*sp
,
2313 struct kvm_mmu_page
*child
;
2316 if (is_shadow_present_pte(pte
)) {
2317 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
2319 rmap_remove(vcpu
->kvm
, spte
);
2321 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2322 mmu_page_remove_parent_pte(child
, spte
);
2325 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
2326 if (is_large_pte(pte
))
2327 --vcpu
->kvm
->stat
.lpages
;
2330 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
2331 struct kvm_mmu_page
*sp
,
2335 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
2336 if (!vcpu
->arch
.update_pte
.largepage
||
2337 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2338 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
2343 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
2344 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
2345 paging32_update_pte(vcpu
, sp
, spte
, new);
2347 paging64_update_pte(vcpu
, sp
, spte
, new);
2350 static bool need_remote_flush(u64 old
, u64
new)
2352 if (!is_shadow_present_pte(old
))
2354 if (!is_shadow_present_pte(new))
2356 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
2358 old
^= PT64_NX_MASK
;
2359 new ^= PT64_NX_MASK
;
2360 return (old
& ~new & PT64_PERM_MASK
) != 0;
2363 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
2365 if (need_remote_flush(old
, new))
2366 kvm_flush_remote_tlbs(vcpu
->kvm
);
2368 kvm_mmu_flush_tlb(vcpu
);
2371 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
2373 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2375 return !!(spte
&& (*spte
& shadow_accessed_mask
));
2378 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2379 const u8
*new, int bytes
)
2386 vcpu
->arch
.update_pte
.largepage
= 0;
2388 if (bytes
!= 4 && bytes
!= 8)
2392 * Assume that the pte write on a page table of the same type
2393 * as the current vcpu paging mode. This is nearly always true
2394 * (might be false while changing modes). Note it is verified later
2398 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2399 if ((bytes
== 4) && (gpa
% 4 == 0)) {
2400 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
2403 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
2404 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
2405 memcpy((void *)&gpte
, new, 8);
2408 if ((bytes
== 4) && (gpa
% 4 == 0))
2409 memcpy((void *)&gpte
, new, 4);
2411 if (!is_present_pte(gpte
))
2413 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
2415 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
2416 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2417 vcpu
->arch
.update_pte
.largepage
= 1;
2419 vcpu
->arch
.update_pte
.mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2421 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2423 if (is_error_pfn(pfn
)) {
2424 kvm_release_pfn_clean(pfn
);
2427 vcpu
->arch
.update_pte
.gfn
= gfn
;
2428 vcpu
->arch
.update_pte
.pfn
= pfn
;
2431 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2433 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2436 && vcpu
->arch
.last_pte_gfn
== gfn
2437 && shadow_accessed_mask
2438 && !(*spte
& shadow_accessed_mask
)
2439 && is_shadow_present_pte(*spte
))
2440 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
2443 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2444 const u8
*new, int bytes
,
2445 bool guest_initiated
)
2447 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2448 struct kvm_mmu_page
*sp
;
2449 struct hlist_node
*node
, *n
;
2450 struct hlist_head
*bucket
;
2454 unsigned offset
= offset_in_page(gpa
);
2456 unsigned page_offset
;
2457 unsigned misaligned
;
2464 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
2465 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
2466 spin_lock(&vcpu
->kvm
->mmu_lock
);
2467 kvm_mmu_access_page(vcpu
, gfn
);
2468 kvm_mmu_free_some_pages(vcpu
);
2469 ++vcpu
->kvm
->stat
.mmu_pte_write
;
2470 kvm_mmu_audit(vcpu
, "pre pte write");
2471 if (guest_initiated
) {
2472 if (gfn
== vcpu
->arch
.last_pt_write_gfn
2473 && !last_updated_pte_accessed(vcpu
)) {
2474 ++vcpu
->arch
.last_pt_write_count
;
2475 if (vcpu
->arch
.last_pt_write_count
>= 3)
2478 vcpu
->arch
.last_pt_write_gfn
= gfn
;
2479 vcpu
->arch
.last_pt_write_count
= 1;
2480 vcpu
->arch
.last_pte_updated
= NULL
;
2483 index
= kvm_page_table_hashfn(gfn
);
2484 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
2485 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
2486 if (sp
->gfn
!= gfn
|| sp
->role
.direct
|| sp
->role
.invalid
)
2488 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
2489 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
2490 misaligned
|= bytes
< 4;
2491 if (misaligned
|| flooded
) {
2493 * Misaligned accesses are too much trouble to fix
2494 * up; also, they usually indicate a page is not used
2497 * If we're seeing too many writes to a page,
2498 * it may no longer be a page table, or we may be
2499 * forking, in which case it is better to unmap the
2502 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2503 gpa
, bytes
, sp
->role
.word
);
2504 if (kvm_mmu_zap_page(vcpu
->kvm
, sp
))
2506 ++vcpu
->kvm
->stat
.mmu_flooded
;
2509 page_offset
= offset
;
2510 level
= sp
->role
.level
;
2512 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2513 page_offset
<<= 1; /* 32->64 */
2515 * A 32-bit pde maps 4MB while the shadow pdes map
2516 * only 2MB. So we need to double the offset again
2517 * and zap two pdes instead of one.
2519 if (level
== PT32_ROOT_LEVEL
) {
2520 page_offset
&= ~7; /* kill rounding error */
2524 quadrant
= page_offset
>> PAGE_SHIFT
;
2525 page_offset
&= ~PAGE_MASK
;
2526 if (quadrant
!= sp
->role
.quadrant
)
2529 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
2530 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
2532 r
= kvm_read_guest_atomic(vcpu
->kvm
,
2533 gpa
& ~(u64
)(pte_size
- 1),
2535 new = (const void *)&gentry
;
2541 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
2543 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
2544 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
2548 kvm_mmu_audit(vcpu
, "post pte write");
2549 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2550 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
2551 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
2552 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2556 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
2561 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
2563 spin_lock(&vcpu
->kvm
->mmu_lock
);
2564 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
2565 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2568 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
2570 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
2572 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
2573 struct kvm_mmu_page
*sp
;
2575 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
2576 struct kvm_mmu_page
, link
);
2577 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2578 ++vcpu
->kvm
->stat
.mmu_recycled
;
2582 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
2585 enum emulation_result er
;
2587 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
2596 r
= mmu_topup_memory_caches(vcpu
);
2600 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
2605 case EMULATE_DO_MMIO
:
2606 ++vcpu
->stat
.mmio_exits
;
2609 kvm_report_emulation_failure(vcpu
, "pagetable");
2617 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
2619 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
2621 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
2622 kvm_mmu_flush_tlb(vcpu
);
2623 ++vcpu
->stat
.invlpg
;
2625 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
2627 void kvm_enable_tdp(void)
2631 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
2633 void kvm_disable_tdp(void)
2635 tdp_enabled
= false;
2637 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
2639 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
2641 struct kvm_mmu_page
*sp
;
2643 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
2644 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
2645 struct kvm_mmu_page
, link
);
2646 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2649 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
2652 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
2659 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
2660 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2661 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
2663 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2664 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
2666 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2667 * Therefore we need to allocate shadow page tables in the first
2668 * 4GB of memory, which happens to fit the DMA32 zone.
2670 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
2673 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
2674 for (i
= 0; i
< 4; ++i
)
2675 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2680 free_mmu_pages(vcpu
);
2684 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
2687 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2689 return alloc_mmu_pages(vcpu
);
2692 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
2695 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2697 return init_kvm_mmu(vcpu
);
2700 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
2704 destroy_kvm_mmu(vcpu
);
2705 free_mmu_pages(vcpu
);
2706 mmu_free_memory_caches(vcpu
);
2709 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
2711 struct kvm_mmu_page
*sp
;
2713 spin_lock(&kvm
->mmu_lock
);
2714 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
2718 if (!test_bit(slot
, sp
->slot_bitmap
))
2722 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
2724 if (pt
[i
] & PT_WRITABLE_MASK
)
2725 pt
[i
] &= ~PT_WRITABLE_MASK
;
2727 kvm_flush_remote_tlbs(kvm
);
2728 spin_unlock(&kvm
->mmu_lock
);
2731 void kvm_mmu_zap_all(struct kvm
*kvm
)
2733 struct kvm_mmu_page
*sp
, *node
;
2735 spin_lock(&kvm
->mmu_lock
);
2736 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
2737 if (kvm_mmu_zap_page(kvm
, sp
))
2738 node
= container_of(kvm
->arch
.active_mmu_pages
.next
,
2739 struct kvm_mmu_page
, link
);
2740 spin_unlock(&kvm
->mmu_lock
);
2742 kvm_flush_remote_tlbs(kvm
);
2745 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
2747 struct kvm_mmu_page
*page
;
2749 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
2750 struct kvm_mmu_page
, link
);
2751 kvm_mmu_zap_page(kvm
, page
);
2754 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
2757 struct kvm
*kvm_freed
= NULL
;
2758 int cache_count
= 0;
2760 spin_lock(&kvm_lock
);
2762 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
2765 if (!down_read_trylock(&kvm
->slots_lock
))
2767 spin_lock(&kvm
->mmu_lock
);
2768 npages
= kvm
->arch
.n_alloc_mmu_pages
-
2769 kvm
->arch
.n_free_mmu_pages
;
2770 cache_count
+= npages
;
2771 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
2772 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
2778 spin_unlock(&kvm
->mmu_lock
);
2779 up_read(&kvm
->slots_lock
);
2782 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
2784 spin_unlock(&kvm_lock
);
2789 static struct shrinker mmu_shrinker
= {
2790 .shrink
= mmu_shrink
,
2791 .seeks
= DEFAULT_SEEKS
* 10,
2794 static void mmu_destroy_caches(void)
2796 if (pte_chain_cache
)
2797 kmem_cache_destroy(pte_chain_cache
);
2798 if (rmap_desc_cache
)
2799 kmem_cache_destroy(rmap_desc_cache
);
2800 if (mmu_page_header_cache
)
2801 kmem_cache_destroy(mmu_page_header_cache
);
2804 void kvm_mmu_module_exit(void)
2806 mmu_destroy_caches();
2807 unregister_shrinker(&mmu_shrinker
);
2810 int kvm_mmu_module_init(void)
2812 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2813 sizeof(struct kvm_pte_chain
),
2815 if (!pte_chain_cache
)
2817 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2818 sizeof(struct kvm_rmap_desc
),
2820 if (!rmap_desc_cache
)
2823 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2824 sizeof(struct kvm_mmu_page
),
2826 if (!mmu_page_header_cache
)
2829 register_shrinker(&mmu_shrinker
);
2834 mmu_destroy_caches();
2839 * Caculate mmu pages needed for kvm.
2841 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2844 unsigned int nr_mmu_pages
;
2845 unsigned int nr_pages
= 0;
2847 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2848 nr_pages
+= kvm
->memslots
[i
].npages
;
2850 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2851 nr_mmu_pages
= max(nr_mmu_pages
,
2852 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2854 return nr_mmu_pages
;
2857 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2860 if (len
> buffer
->len
)
2865 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2870 ret
= pv_mmu_peek_buffer(buffer
, len
);
2875 buffer
->processed
+= len
;
2879 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2880 gpa_t addr
, gpa_t value
)
2885 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2888 r
= mmu_topup_memory_caches(vcpu
);
2892 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2898 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2900 kvm_x86_ops
->tlb_flush(vcpu
);
2901 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
2905 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2907 spin_lock(&vcpu
->kvm
->mmu_lock
);
2908 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2909 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2913 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2914 struct kvm_pv_mmu_op_buffer
*buffer
)
2916 struct kvm_mmu_op_header
*header
;
2918 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2921 switch (header
->op
) {
2922 case KVM_MMU_OP_WRITE_PTE
: {
2923 struct kvm_mmu_op_write_pte
*wpte
;
2925 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2928 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2931 case KVM_MMU_OP_FLUSH_TLB
: {
2932 struct kvm_mmu_op_flush_tlb
*ftlb
;
2934 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2937 return kvm_pv_mmu_flush_tlb(vcpu
);
2939 case KVM_MMU_OP_RELEASE_PT
: {
2940 struct kvm_mmu_op_release_pt
*rpt
;
2942 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2945 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2951 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2952 gpa_t addr
, unsigned long *ret
)
2955 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
2957 buffer
->ptr
= buffer
->buf
;
2958 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
2959 buffer
->processed
= 0;
2961 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
2965 while (buffer
->len
) {
2966 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
2975 *ret
= buffer
->processed
;
2981 static const char *audit_msg
;
2983 static gva_t
canonicalize(gva_t gva
)
2985 #ifdef CONFIG_X86_64
2986 gva
= (long long)(gva
<< 16) >> 16;
2991 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2992 gva_t va
, int level
)
2994 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
2996 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
2998 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
3001 if (ent
== shadow_trap_nonpresent_pte
)
3004 va
= canonicalize(va
);
3006 if (ent
== shadow_notrap_nonpresent_pte
)
3007 printk(KERN_ERR
"audit: (%s) nontrapping pte"
3008 " in nonleaf level: levels %d gva %lx"
3009 " level %d pte %llx\n", audit_msg
,
3010 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
3012 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
3014 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
3015 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
3017 if (is_shadow_present_pte(ent
)
3018 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
3019 printk(KERN_ERR
"xx audit error: (%s) levels %d"
3020 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
3021 audit_msg
, vcpu
->arch
.mmu
.root_level
,
3023 is_shadow_present_pte(ent
));
3024 else if (ent
== shadow_notrap_nonpresent_pte
3025 && !is_error_hpa(hpa
))
3026 printk(KERN_ERR
"audit: (%s) notrap shadow,"
3027 " valid guest gva %lx\n", audit_msg
, va
);
3028 kvm_release_pfn_clean(pfn
);
3034 static void audit_mappings(struct kvm_vcpu
*vcpu
)
3038 if (vcpu
->arch
.mmu
.root_level
== 4)
3039 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
3041 for (i
= 0; i
< 4; ++i
)
3042 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
3043 audit_mappings_page(vcpu
,
3044 vcpu
->arch
.mmu
.pae_root
[i
],
3049 static int count_rmaps(struct kvm_vcpu
*vcpu
)
3054 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
3055 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
3056 struct kvm_rmap_desc
*d
;
3058 for (j
= 0; j
< m
->npages
; ++j
) {
3059 unsigned long *rmapp
= &m
->rmap
[j
];
3063 if (!(*rmapp
& 1)) {
3067 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
3069 for (k
= 0; k
< RMAP_EXT
; ++k
)
3070 if (d
->shadow_ptes
[k
])
3081 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
3084 struct kvm_mmu_page
*sp
;
3087 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3090 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
3093 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3096 if (!(ent
& PT_PRESENT_MASK
))
3098 if (!(ent
& PT_WRITABLE_MASK
))
3106 static void audit_rmap(struct kvm_vcpu
*vcpu
)
3108 int n_rmap
= count_rmaps(vcpu
);
3109 int n_actual
= count_writable_mappings(vcpu
);
3111 if (n_rmap
!= n_actual
)
3112 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
3113 __func__
, audit_msg
, n_rmap
, n_actual
);
3116 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
3118 struct kvm_mmu_page
*sp
;
3119 struct kvm_memory_slot
*slot
;
3120 unsigned long *rmapp
;
3123 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3124 if (sp
->role
.direct
)
3127 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
3128 slot
= gfn_to_memslot_unaliased(vcpu
->kvm
, sp
->gfn
);
3129 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
3131 printk(KERN_ERR
"%s: (%s) shadow page has writable"
3132 " mappings: gfn %lx role %x\n",
3133 __func__
, audit_msg
, sp
->gfn
,
3138 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
3145 audit_write_protection(vcpu
);
3146 audit_mappings(vcpu
);