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
{
149 int (*entry
)(struct kvm_shadow_walk
*walk
, struct kvm_vcpu
*vcpu
,
150 u64 addr
, u64
*spte
, int level
);
153 struct kvm_unsync_walk
{
154 int (*entry
) (struct kvm_mmu_page
*sp
, struct kvm_unsync_walk
*walk
);
157 typedef int (*mmu_parent_walk_fn
) (struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
);
159 static struct kmem_cache
*pte_chain_cache
;
160 static struct kmem_cache
*rmap_desc_cache
;
161 static struct kmem_cache
*mmu_page_header_cache
;
163 static u64 __read_mostly shadow_trap_nonpresent_pte
;
164 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
165 static u64 __read_mostly shadow_base_present_pte
;
166 static u64 __read_mostly shadow_nx_mask
;
167 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
168 static u64 __read_mostly shadow_user_mask
;
169 static u64 __read_mostly shadow_accessed_mask
;
170 static u64 __read_mostly shadow_dirty_mask
;
171 static u64 __read_mostly shadow_mt_mask
;
173 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
175 shadow_trap_nonpresent_pte
= trap_pte
;
176 shadow_notrap_nonpresent_pte
= notrap_pte
;
178 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
180 void kvm_mmu_set_base_ptes(u64 base_pte
)
182 shadow_base_present_pte
= base_pte
;
184 EXPORT_SYMBOL_GPL(kvm_mmu_set_base_ptes
);
186 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
187 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
, u64 mt_mask
)
189 shadow_user_mask
= user_mask
;
190 shadow_accessed_mask
= accessed_mask
;
191 shadow_dirty_mask
= dirty_mask
;
192 shadow_nx_mask
= nx_mask
;
193 shadow_x_mask
= x_mask
;
194 shadow_mt_mask
= mt_mask
;
196 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
198 static int is_write_protection(struct kvm_vcpu
*vcpu
)
200 return vcpu
->arch
.cr0
& X86_CR0_WP
;
203 static int is_cpuid_PSE36(void)
208 static int is_nx(struct kvm_vcpu
*vcpu
)
210 return vcpu
->arch
.shadow_efer
& EFER_NX
;
213 static int is_present_pte(unsigned long pte
)
215 return pte
& PT_PRESENT_MASK
;
218 static int is_shadow_present_pte(u64 pte
)
220 return pte
!= shadow_trap_nonpresent_pte
221 && pte
!= shadow_notrap_nonpresent_pte
;
224 static int is_large_pte(u64 pte
)
226 return pte
& PT_PAGE_SIZE_MASK
;
229 static int is_writeble_pte(unsigned long pte
)
231 return pte
& PT_WRITABLE_MASK
;
234 static int is_dirty_pte(unsigned long pte
)
236 return pte
& shadow_dirty_mask
;
239 static int is_rmap_pte(u64 pte
)
241 return is_shadow_present_pte(pte
);
244 static pfn_t
spte_to_pfn(u64 pte
)
246 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
249 static gfn_t
pse36_gfn_delta(u32 gpte
)
251 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
253 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
256 static void set_shadow_pte(u64
*sptep
, u64 spte
)
259 set_64bit((unsigned long *)sptep
, spte
);
261 set_64bit((unsigned long long *)sptep
, spte
);
265 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
266 struct kmem_cache
*base_cache
, int min
)
270 if (cache
->nobjs
>= min
)
272 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
273 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
276 cache
->objects
[cache
->nobjs
++] = obj
;
281 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
)
284 kfree(mc
->objects
[--mc
->nobjs
]);
287 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
292 if (cache
->nobjs
>= min
)
294 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
295 page
= alloc_page(GFP_KERNEL
);
298 set_page_private(page
, 0);
299 cache
->objects
[cache
->nobjs
++] = page_address(page
);
304 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
307 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
310 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
314 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
,
318 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
,
322 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
325 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
326 mmu_page_header_cache
, 4);
331 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
333 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_chain_cache
);
334 mmu_free_memory_cache(&vcpu
->arch
.mmu_rmap_desc_cache
);
335 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
336 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
);
339 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
345 p
= mc
->objects
[--mc
->nobjs
];
350 static struct kvm_pte_chain
*mmu_alloc_pte_chain(struct kvm_vcpu
*vcpu
)
352 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_chain_cache
,
353 sizeof(struct kvm_pte_chain
));
356 static void mmu_free_pte_chain(struct kvm_pte_chain
*pc
)
361 static struct kvm_rmap_desc
*mmu_alloc_rmap_desc(struct kvm_vcpu
*vcpu
)
363 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_rmap_desc_cache
,
364 sizeof(struct kvm_rmap_desc
));
367 static void mmu_free_rmap_desc(struct kvm_rmap_desc
*rd
)
373 * Return the pointer to the largepage write count for a given
374 * gfn, handling slots that are not large page aligned.
376 static int *slot_largepage_idx(gfn_t gfn
, struct kvm_memory_slot
*slot
)
380 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
381 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
382 return &slot
->lpage_info
[idx
].write_count
;
385 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
389 gfn
= unalias_gfn(kvm
, gfn
);
390 write_count
= slot_largepage_idx(gfn
,
391 gfn_to_memslot_unaliased(kvm
, gfn
));
395 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
399 gfn
= unalias_gfn(kvm
, gfn
);
400 write_count
= slot_largepage_idx(gfn
,
401 gfn_to_memslot_unaliased(kvm
, gfn
));
403 WARN_ON(*write_count
< 0);
406 static int has_wrprotected_page(struct kvm
*kvm
, gfn_t gfn
)
408 struct kvm_memory_slot
*slot
;
411 gfn
= unalias_gfn(kvm
, gfn
);
412 slot
= gfn_to_memslot_unaliased(kvm
, gfn
);
414 largepage_idx
= slot_largepage_idx(gfn
, slot
);
415 return *largepage_idx
;
421 static int host_largepage_backed(struct kvm
*kvm
, gfn_t gfn
)
423 struct vm_area_struct
*vma
;
427 addr
= gfn_to_hva(kvm
, gfn
);
428 if (kvm_is_error_hva(addr
))
431 down_read(¤t
->mm
->mmap_sem
);
432 vma
= find_vma(current
->mm
, addr
);
433 if (vma
&& is_vm_hugetlb_page(vma
))
435 up_read(¤t
->mm
->mmap_sem
);
440 static int is_largepage_backed(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
442 struct kvm_memory_slot
*slot
;
444 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
))
447 if (!host_largepage_backed(vcpu
->kvm
, large_gfn
))
450 slot
= gfn_to_memslot(vcpu
->kvm
, large_gfn
);
451 if (slot
&& slot
->dirty_bitmap
)
458 * Take gfn and return the reverse mapping to it.
459 * Note: gfn must be unaliased before this function get called
462 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int lpage
)
464 struct kvm_memory_slot
*slot
;
467 slot
= gfn_to_memslot(kvm
, gfn
);
469 return &slot
->rmap
[gfn
- slot
->base_gfn
];
471 idx
= (gfn
/ KVM_PAGES_PER_HPAGE
) -
472 (slot
->base_gfn
/ KVM_PAGES_PER_HPAGE
);
474 return &slot
->lpage_info
[idx
].rmap_pde
;
478 * Reverse mapping data structures:
480 * If rmapp bit zero is zero, then rmapp point to the shadw page table entry
481 * that points to page_address(page).
483 * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc
484 * containing more mappings.
486 static void rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
, int lpage
)
488 struct kvm_mmu_page
*sp
;
489 struct kvm_rmap_desc
*desc
;
490 unsigned long *rmapp
;
493 if (!is_rmap_pte(*spte
))
495 gfn
= unalias_gfn(vcpu
->kvm
, gfn
);
496 sp
= page_header(__pa(spte
));
497 sp
->gfns
[spte
- sp
->spt
] = gfn
;
498 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, lpage
);
500 rmap_printk("rmap_add: %p %llx 0->1\n", spte
, *spte
);
501 *rmapp
= (unsigned long)spte
;
502 } else if (!(*rmapp
& 1)) {
503 rmap_printk("rmap_add: %p %llx 1->many\n", spte
, *spte
);
504 desc
= mmu_alloc_rmap_desc(vcpu
);
505 desc
->shadow_ptes
[0] = (u64
*)*rmapp
;
506 desc
->shadow_ptes
[1] = spte
;
507 *rmapp
= (unsigned long)desc
| 1;
509 rmap_printk("rmap_add: %p %llx many->many\n", spte
, *spte
);
510 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
511 while (desc
->shadow_ptes
[RMAP_EXT
-1] && desc
->more
)
513 if (desc
->shadow_ptes
[RMAP_EXT
-1]) {
514 desc
->more
= mmu_alloc_rmap_desc(vcpu
);
517 for (i
= 0; desc
->shadow_ptes
[i
]; ++i
)
519 desc
->shadow_ptes
[i
] = spte
;
523 static void rmap_desc_remove_entry(unsigned long *rmapp
,
524 struct kvm_rmap_desc
*desc
,
526 struct kvm_rmap_desc
*prev_desc
)
530 for (j
= RMAP_EXT
- 1; !desc
->shadow_ptes
[j
] && j
> i
; --j
)
532 desc
->shadow_ptes
[i
] = desc
->shadow_ptes
[j
];
533 desc
->shadow_ptes
[j
] = NULL
;
536 if (!prev_desc
&& !desc
->more
)
537 *rmapp
= (unsigned long)desc
->shadow_ptes
[0];
540 prev_desc
->more
= desc
->more
;
542 *rmapp
= (unsigned long)desc
->more
| 1;
543 mmu_free_rmap_desc(desc
);
546 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
548 struct kvm_rmap_desc
*desc
;
549 struct kvm_rmap_desc
*prev_desc
;
550 struct kvm_mmu_page
*sp
;
552 unsigned long *rmapp
;
555 if (!is_rmap_pte(*spte
))
557 sp
= page_header(__pa(spte
));
558 pfn
= spte_to_pfn(*spte
);
559 if (*spte
& shadow_accessed_mask
)
560 kvm_set_pfn_accessed(pfn
);
561 if (is_writeble_pte(*spte
))
562 kvm_release_pfn_dirty(pfn
);
564 kvm_release_pfn_clean(pfn
);
565 rmapp
= gfn_to_rmap(kvm
, sp
->gfns
[spte
- sp
->spt
], is_large_pte(*spte
));
567 printk(KERN_ERR
"rmap_remove: %p %llx 0->BUG\n", spte
, *spte
);
569 } else if (!(*rmapp
& 1)) {
570 rmap_printk("rmap_remove: %p %llx 1->0\n", spte
, *spte
);
571 if ((u64
*)*rmapp
!= spte
) {
572 printk(KERN_ERR
"rmap_remove: %p %llx 1->BUG\n",
578 rmap_printk("rmap_remove: %p %llx many->many\n", spte
, *spte
);
579 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
582 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
)
583 if (desc
->shadow_ptes
[i
] == spte
) {
584 rmap_desc_remove_entry(rmapp
,
596 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
598 struct kvm_rmap_desc
*desc
;
599 struct kvm_rmap_desc
*prev_desc
;
605 else if (!(*rmapp
& 1)) {
607 return (u64
*)*rmapp
;
610 desc
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
614 for (i
= 0; i
< RMAP_EXT
&& desc
->shadow_ptes
[i
]; ++i
) {
615 if (prev_spte
== spte
)
616 return desc
->shadow_ptes
[i
];
617 prev_spte
= desc
->shadow_ptes
[i
];
624 static int rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
626 unsigned long *rmapp
;
628 int write_protected
= 0;
630 gfn
= unalias_gfn(kvm
, gfn
);
631 rmapp
= gfn_to_rmap(kvm
, gfn
, 0);
633 spte
= rmap_next(kvm
, rmapp
, NULL
);
636 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
637 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
638 if (is_writeble_pte(*spte
)) {
639 set_shadow_pte(spte
, *spte
& ~PT_WRITABLE_MASK
);
642 spte
= rmap_next(kvm
, rmapp
, spte
);
644 if (write_protected
) {
647 spte
= rmap_next(kvm
, rmapp
, NULL
);
648 pfn
= spte_to_pfn(*spte
);
649 kvm_set_pfn_dirty(pfn
);
652 /* check for huge page mappings */
653 rmapp
= gfn_to_rmap(kvm
, gfn
, 1);
654 spte
= rmap_next(kvm
, rmapp
, NULL
);
657 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
658 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
659 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
660 if (is_writeble_pte(*spte
)) {
661 rmap_remove(kvm
, spte
);
663 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
667 spte
= rmap_next(kvm
, rmapp
, spte
);
670 return write_protected
;
673 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
676 int need_tlb_flush
= 0;
678 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
679 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
680 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
681 rmap_remove(kvm
, spte
);
682 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
685 return need_tlb_flush
;
688 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
689 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
))
695 * If mmap_sem isn't taken, we can look the memslots with only
696 * the mmu_lock by skipping over the slots with userspace_addr == 0.
698 for (i
= 0; i
< kvm
->nmemslots
; i
++) {
699 struct kvm_memory_slot
*memslot
= &kvm
->memslots
[i
];
700 unsigned long start
= memslot
->userspace_addr
;
703 /* mmu_lock protects userspace_addr */
707 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
708 if (hva
>= start
&& hva
< end
) {
709 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
710 retval
|= handler(kvm
, &memslot
->rmap
[gfn_offset
]);
711 retval
|= handler(kvm
,
712 &memslot
->lpage_info
[
714 KVM_PAGES_PER_HPAGE
].rmap_pde
);
721 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
723 return kvm_handle_hva(kvm
, hva
, kvm_unmap_rmapp
);
726 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
)
731 /* always return old for EPT */
732 if (!shadow_accessed_mask
)
735 spte
= rmap_next(kvm
, rmapp
, NULL
);
739 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
740 _young
= _spte
& PT_ACCESSED_MASK
;
743 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
745 spte
= rmap_next(kvm
, rmapp
, spte
);
750 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
752 return kvm_handle_hva(kvm
, hva
, kvm_age_rmapp
);
756 static int is_empty_shadow_page(u64
*spt
)
761 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
762 if (is_shadow_present_pte(*pos
)) {
763 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
771 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
773 ASSERT(is_empty_shadow_page(sp
->spt
));
775 __free_page(virt_to_page(sp
->spt
));
776 __free_page(virt_to_page(sp
->gfns
));
778 ++kvm
->arch
.n_free_mmu_pages
;
781 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
783 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
786 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
789 struct kvm_mmu_page
*sp
;
791 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
, sizeof *sp
);
792 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
793 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
794 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
795 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
796 INIT_LIST_HEAD(&sp
->oos_link
);
797 ASSERT(is_empty_shadow_page(sp
->spt
));
798 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
801 sp
->parent_pte
= parent_pte
;
802 --vcpu
->kvm
->arch
.n_free_mmu_pages
;
806 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
807 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
809 struct kvm_pte_chain
*pte_chain
;
810 struct hlist_node
*node
;
815 if (!sp
->multimapped
) {
816 u64
*old
= sp
->parent_pte
;
819 sp
->parent_pte
= parent_pte
;
823 pte_chain
= mmu_alloc_pte_chain(vcpu
);
824 INIT_HLIST_HEAD(&sp
->parent_ptes
);
825 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
826 pte_chain
->parent_ptes
[0] = old
;
828 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
) {
829 if (pte_chain
->parent_ptes
[NR_PTE_CHAIN_ENTRIES
-1])
831 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
)
832 if (!pte_chain
->parent_ptes
[i
]) {
833 pte_chain
->parent_ptes
[i
] = parent_pte
;
837 pte_chain
= mmu_alloc_pte_chain(vcpu
);
839 hlist_add_head(&pte_chain
->link
, &sp
->parent_ptes
);
840 pte_chain
->parent_ptes
[0] = parent_pte
;
843 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
846 struct kvm_pte_chain
*pte_chain
;
847 struct hlist_node
*node
;
850 if (!sp
->multimapped
) {
851 BUG_ON(sp
->parent_pte
!= parent_pte
);
852 sp
->parent_pte
= NULL
;
855 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
856 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
857 if (!pte_chain
->parent_ptes
[i
])
859 if (pte_chain
->parent_ptes
[i
] != parent_pte
)
861 while (i
+ 1 < NR_PTE_CHAIN_ENTRIES
862 && pte_chain
->parent_ptes
[i
+ 1]) {
863 pte_chain
->parent_ptes
[i
]
864 = pte_chain
->parent_ptes
[i
+ 1];
867 pte_chain
->parent_ptes
[i
] = NULL
;
869 hlist_del(&pte_chain
->link
);
870 mmu_free_pte_chain(pte_chain
);
871 if (hlist_empty(&sp
->parent_ptes
)) {
873 sp
->parent_pte
= NULL
;
882 static void mmu_parent_walk(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
883 mmu_parent_walk_fn fn
)
885 struct kvm_pte_chain
*pte_chain
;
886 struct hlist_node
*node
;
887 struct kvm_mmu_page
*parent_sp
;
890 if (!sp
->multimapped
&& sp
->parent_pte
) {
891 parent_sp
= page_header(__pa(sp
->parent_pte
));
893 mmu_parent_walk(vcpu
, parent_sp
, fn
);
896 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
897 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
898 if (!pte_chain
->parent_ptes
[i
])
900 parent_sp
= page_header(__pa(pte_chain
->parent_ptes
[i
]));
902 mmu_parent_walk(vcpu
, parent_sp
, fn
);
906 static void kvm_mmu_update_unsync_bitmap(u64
*spte
)
909 struct kvm_mmu_page
*sp
= page_header(__pa(spte
));
911 index
= spte
- sp
->spt
;
912 if (!__test_and_set_bit(index
, sp
->unsync_child_bitmap
))
913 sp
->unsync_children
++;
914 WARN_ON(!sp
->unsync_children
);
917 static void kvm_mmu_update_parents_unsync(struct kvm_mmu_page
*sp
)
919 struct kvm_pte_chain
*pte_chain
;
920 struct hlist_node
*node
;
926 if (!sp
->multimapped
) {
927 kvm_mmu_update_unsync_bitmap(sp
->parent_pte
);
931 hlist_for_each_entry(pte_chain
, node
, &sp
->parent_ptes
, link
)
932 for (i
= 0; i
< NR_PTE_CHAIN_ENTRIES
; ++i
) {
933 if (!pte_chain
->parent_ptes
[i
])
935 kvm_mmu_update_unsync_bitmap(pte_chain
->parent_ptes
[i
]);
939 static int unsync_walk_fn(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
941 kvm_mmu_update_parents_unsync(sp
);
945 static void kvm_mmu_mark_parents_unsync(struct kvm_vcpu
*vcpu
,
946 struct kvm_mmu_page
*sp
)
948 mmu_parent_walk(vcpu
, sp
, unsync_walk_fn
);
949 kvm_mmu_update_parents_unsync(sp
);
952 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
953 struct kvm_mmu_page
*sp
)
957 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
958 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
961 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
962 struct kvm_mmu_page
*sp
)
967 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
971 #define KVM_PAGE_ARRAY_NR 16
973 struct kvm_mmu_pages
{
974 struct mmu_page_and_offset
{
975 struct kvm_mmu_page
*sp
;
977 } page
[KVM_PAGE_ARRAY_NR
];
981 #define for_each_unsync_children(bitmap, idx) \
982 for (idx = find_first_bit(bitmap, 512); \
984 idx = find_next_bit(bitmap, 512, idx+1))
986 int mmu_pages_add(struct kvm_mmu_pages
*pvec
, struct kvm_mmu_page
*sp
,
992 for (i
=0; i
< pvec
->nr
; i
++)
993 if (pvec
->page
[i
].sp
== sp
)
996 pvec
->page
[pvec
->nr
].sp
= sp
;
997 pvec
->page
[pvec
->nr
].idx
= idx
;
999 return (pvec
->nr
== KVM_PAGE_ARRAY_NR
);
1002 static int __mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1003 struct kvm_mmu_pages
*pvec
)
1005 int i
, ret
, nr_unsync_leaf
= 0;
1007 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
1008 u64 ent
= sp
->spt
[i
];
1010 if (is_shadow_present_pte(ent
)) {
1011 struct kvm_mmu_page
*child
;
1012 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
1014 if (child
->unsync_children
) {
1015 if (mmu_pages_add(pvec
, child
, i
))
1018 ret
= __mmu_unsync_walk(child
, pvec
);
1020 __clear_bit(i
, sp
->unsync_child_bitmap
);
1022 nr_unsync_leaf
+= ret
;
1027 if (child
->unsync
) {
1029 if (mmu_pages_add(pvec
, child
, i
))
1035 if (find_first_bit(sp
->unsync_child_bitmap
, 512) == 512)
1036 sp
->unsync_children
= 0;
1038 return nr_unsync_leaf
;
1041 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1042 struct kvm_mmu_pages
*pvec
)
1044 if (!sp
->unsync_children
)
1047 mmu_pages_add(pvec
, sp
, 0);
1048 return __mmu_unsync_walk(sp
, pvec
);
1051 static struct kvm_mmu_page
*kvm_mmu_lookup_page(struct kvm
*kvm
, gfn_t gfn
)
1054 struct hlist_head
*bucket
;
1055 struct kvm_mmu_page
*sp
;
1056 struct hlist_node
*node
;
1058 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1059 index
= kvm_page_table_hashfn(gfn
);
1060 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1061 hlist_for_each_entry(sp
, node
, bucket
, hash_link
)
1062 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
1063 && !sp
->role
.invalid
) {
1064 pgprintk("%s: found role %x\n",
1065 __func__
, sp
->role
.word
);
1071 static void kvm_unlink_unsync_global(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1073 list_del(&sp
->oos_link
);
1074 --kvm
->stat
.mmu_unsync_global
;
1077 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1079 WARN_ON(!sp
->unsync
);
1082 kvm_unlink_unsync_global(kvm
, sp
);
1083 --kvm
->stat
.mmu_unsync
;
1086 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
);
1088 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1090 if (sp
->role
.glevels
!= vcpu
->arch
.mmu
.root_level
) {
1091 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1095 if (rmap_write_protect(vcpu
->kvm
, sp
->gfn
))
1096 kvm_flush_remote_tlbs(vcpu
->kvm
);
1097 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1098 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1099 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1103 kvm_mmu_flush_tlb(vcpu
);
1107 struct mmu_page_path
{
1108 struct kvm_mmu_page
*parent
[PT64_ROOT_LEVEL
-1];
1109 unsigned int idx
[PT64_ROOT_LEVEL
-1];
1112 #define for_each_sp(pvec, sp, parents, i) \
1113 for (i = mmu_pages_next(&pvec, &parents, -1), \
1114 sp = pvec.page[i].sp; \
1115 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1116 i = mmu_pages_next(&pvec, &parents, i))
1118 int mmu_pages_next(struct kvm_mmu_pages
*pvec
, struct mmu_page_path
*parents
,
1123 for (n
= i
+1; n
< pvec
->nr
; n
++) {
1124 struct kvm_mmu_page
*sp
= pvec
->page
[n
].sp
;
1126 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1127 parents
->idx
[0] = pvec
->page
[n
].idx
;
1131 parents
->parent
[sp
->role
.level
-2] = sp
;
1132 parents
->idx
[sp
->role
.level
-1] = pvec
->page
[n
].idx
;
1138 void mmu_pages_clear_parents(struct mmu_page_path
*parents
)
1140 struct kvm_mmu_page
*sp
;
1141 unsigned int level
= 0;
1144 unsigned int idx
= parents
->idx
[level
];
1146 sp
= parents
->parent
[level
];
1150 --sp
->unsync_children
;
1151 WARN_ON((int)sp
->unsync_children
< 0);
1152 __clear_bit(idx
, sp
->unsync_child_bitmap
);
1154 } while (level
< PT64_ROOT_LEVEL
-1 && !sp
->unsync_children
);
1157 static void kvm_mmu_pages_init(struct kvm_mmu_page
*parent
,
1158 struct mmu_page_path
*parents
,
1159 struct kvm_mmu_pages
*pvec
)
1161 parents
->parent
[parent
->role
.level
-1] = NULL
;
1165 static void mmu_sync_children(struct kvm_vcpu
*vcpu
,
1166 struct kvm_mmu_page
*parent
)
1169 struct kvm_mmu_page
*sp
;
1170 struct mmu_page_path parents
;
1171 struct kvm_mmu_pages pages
;
1173 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1174 while (mmu_unsync_walk(parent
, &pages
)) {
1177 for_each_sp(pages
, sp
, parents
, i
)
1178 protected |= rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1181 kvm_flush_remote_tlbs(vcpu
->kvm
);
1183 for_each_sp(pages
, sp
, parents
, i
) {
1184 kvm_sync_page(vcpu
, sp
);
1185 mmu_pages_clear_parents(&parents
);
1187 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1188 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1192 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1200 union kvm_mmu_page_role role
;
1203 struct hlist_head
*bucket
;
1204 struct kvm_mmu_page
*sp
;
1205 struct hlist_node
*node
, *tmp
;
1208 role
.glevels
= vcpu
->arch
.mmu
.root_level
;
1210 role
.metaphysical
= metaphysical
;
1211 role
.access
= access
;
1212 if (vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1213 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1214 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1215 role
.quadrant
= quadrant
;
1217 pgprintk("%s: looking gfn %lx role %x\n", __func__
,
1219 index
= kvm_page_table_hashfn(gfn
);
1220 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1221 hlist_for_each_entry_safe(sp
, node
, tmp
, bucket
, hash_link
)
1222 if (sp
->gfn
== gfn
) {
1224 if (kvm_sync_page(vcpu
, sp
))
1227 if (sp
->role
.word
!= role
.word
)
1230 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1231 if (sp
->unsync_children
) {
1232 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
1233 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1235 pgprintk("%s: found\n", __func__
);
1238 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1239 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
);
1242 pgprintk("%s: adding gfn %lx role %x\n", __func__
, gfn
, role
.word
);
1245 hlist_add_head(&sp
->hash_link
, bucket
);
1246 if (!metaphysical
) {
1247 if (rmap_write_protect(vcpu
->kvm
, gfn
))
1248 kvm_flush_remote_tlbs(vcpu
->kvm
);
1249 account_shadowed(vcpu
->kvm
, gfn
);
1251 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1252 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1254 nonpaging_prefetch_page(vcpu
, sp
);
1258 static int walk_shadow(struct kvm_shadow_walk
*walker
,
1259 struct kvm_vcpu
*vcpu
, u64 addr
)
1267 shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1268 level
= vcpu
->arch
.mmu
.shadow_root_level
;
1269 if (level
== PT32E_ROOT_LEVEL
) {
1270 shadow_addr
= vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1271 shadow_addr
&= PT64_BASE_ADDR_MASK
;
1277 while (level
>= PT_PAGE_TABLE_LEVEL
) {
1278 index
= SHADOW_PT_INDEX(addr
, level
);
1279 sptep
= ((u64
*)__va(shadow_addr
)) + index
;
1280 r
= walker
->entry(walker
, vcpu
, addr
, sptep
, level
);
1283 shadow_addr
= *sptep
& PT64_BASE_ADDR_MASK
;
1289 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1290 struct kvm_mmu_page
*sp
)
1298 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1299 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1300 if (is_shadow_present_pte(pt
[i
]))
1301 rmap_remove(kvm
, &pt
[i
]);
1302 pt
[i
] = shadow_trap_nonpresent_pte
;
1307 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1310 if (is_shadow_present_pte(ent
)) {
1311 if (!is_large_pte(ent
)) {
1312 ent
&= PT64_BASE_ADDR_MASK
;
1313 mmu_page_remove_parent_pte(page_header(ent
),
1317 rmap_remove(kvm
, &pt
[i
]);
1320 pt
[i
] = shadow_trap_nonpresent_pte
;
1324 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1326 mmu_page_remove_parent_pte(sp
, parent_pte
);
1329 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1333 for (i
= 0; i
< KVM_MAX_VCPUS
; ++i
)
1335 kvm
->vcpus
[i
]->arch
.last_pte_updated
= NULL
;
1338 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1342 while (sp
->multimapped
|| sp
->parent_pte
) {
1343 if (!sp
->multimapped
)
1344 parent_pte
= sp
->parent_pte
;
1346 struct kvm_pte_chain
*chain
;
1348 chain
= container_of(sp
->parent_ptes
.first
,
1349 struct kvm_pte_chain
, link
);
1350 parent_pte
= chain
->parent_ptes
[0];
1352 BUG_ON(!parent_pte
);
1353 kvm_mmu_put_page(sp
, parent_pte
);
1354 set_shadow_pte(parent_pte
, shadow_trap_nonpresent_pte
);
1358 static int mmu_zap_unsync_children(struct kvm
*kvm
,
1359 struct kvm_mmu_page
*parent
)
1362 struct mmu_page_path parents
;
1363 struct kvm_mmu_pages pages
;
1365 if (parent
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1368 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1369 while (mmu_unsync_walk(parent
, &pages
)) {
1370 struct kvm_mmu_page
*sp
;
1372 for_each_sp(pages
, sp
, parents
, i
) {
1373 kvm_mmu_zap_page(kvm
, sp
);
1374 mmu_pages_clear_parents(&parents
);
1377 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1383 static int kvm_mmu_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1386 ++kvm
->stat
.mmu_shadow_zapped
;
1387 ret
= mmu_zap_unsync_children(kvm
, sp
);
1388 kvm_mmu_page_unlink_children(kvm
, sp
);
1389 kvm_mmu_unlink_parents(kvm
, sp
);
1390 kvm_flush_remote_tlbs(kvm
);
1391 if (!sp
->role
.invalid
&& !sp
->role
.metaphysical
)
1392 unaccount_shadowed(kvm
, sp
->gfn
);
1394 kvm_unlink_unsync_page(kvm
, sp
);
1395 if (!sp
->root_count
) {
1396 hlist_del(&sp
->hash_link
);
1397 kvm_mmu_free_page(kvm
, sp
);
1399 sp
->role
.invalid
= 1;
1400 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1401 kvm_reload_remote_mmus(kvm
);
1403 kvm_mmu_reset_last_pte_updated(kvm
);
1408 * Changing the number of mmu pages allocated to the vm
1409 * Note: if kvm_nr_mmu_pages is too small, you will get dead lock
1411 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int kvm_nr_mmu_pages
)
1414 * If we set the number of mmu pages to be smaller be than the
1415 * number of actived pages , we must to free some mmu pages before we
1419 if ((kvm
->arch
.n_alloc_mmu_pages
- kvm
->arch
.n_free_mmu_pages
) >
1421 int n_used_mmu_pages
= kvm
->arch
.n_alloc_mmu_pages
1422 - kvm
->arch
.n_free_mmu_pages
;
1424 while (n_used_mmu_pages
> kvm_nr_mmu_pages
) {
1425 struct kvm_mmu_page
*page
;
1427 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1428 struct kvm_mmu_page
, link
);
1429 kvm_mmu_zap_page(kvm
, page
);
1432 kvm
->arch
.n_free_mmu_pages
= 0;
1435 kvm
->arch
.n_free_mmu_pages
+= kvm_nr_mmu_pages
1436 - kvm
->arch
.n_alloc_mmu_pages
;
1438 kvm
->arch
.n_alloc_mmu_pages
= kvm_nr_mmu_pages
;
1441 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1444 struct hlist_head
*bucket
;
1445 struct kvm_mmu_page
*sp
;
1446 struct hlist_node
*node
, *n
;
1449 pgprintk("%s: looking for gfn %lx\n", __func__
, gfn
);
1451 index
= kvm_page_table_hashfn(gfn
);
1452 bucket
= &kvm
->arch
.mmu_page_hash
[index
];
1453 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
)
1454 if (sp
->gfn
== gfn
&& !sp
->role
.metaphysical
) {
1455 pgprintk("%s: gfn %lx role %x\n", __func__
, gfn
,
1458 if (kvm_mmu_zap_page(kvm
, sp
))
1464 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1466 struct kvm_mmu_page
*sp
;
1468 while ((sp
= kvm_mmu_lookup_page(kvm
, gfn
)) != NULL
) {
1469 pgprintk("%s: zap %lx %x\n", __func__
, gfn
, sp
->role
.word
);
1470 kvm_mmu_zap_page(kvm
, sp
);
1474 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1476 int slot
= memslot_id(kvm
, gfn_to_memslot(kvm
, gfn
));
1477 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1479 __set_bit(slot
, sp
->slot_bitmap
);
1482 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1487 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1490 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1491 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1492 set_shadow_pte(&pt
[i
], shadow_trap_nonpresent_pte
);
1496 struct page
*gva_to_page(struct kvm_vcpu
*vcpu
, gva_t gva
)
1500 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
1502 if (gpa
== UNMAPPED_GVA
)
1505 page
= gfn_to_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
1511 * The function is based on mtrr_type_lookup() in
1512 * arch/x86/kernel/cpu/mtrr/generic.c
1514 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1519 u8 prev_match
, curr_match
;
1520 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1522 if (!mtrr_state
->enabled
)
1525 /* Make end inclusive end, instead of exclusive */
1528 /* Look in fixed ranges. Just return the type as per start */
1529 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1532 if (start
< 0x80000) {
1534 idx
+= (start
>> 16);
1535 return mtrr_state
->fixed_ranges
[idx
];
1536 } else if (start
< 0xC0000) {
1538 idx
+= ((start
- 0x80000) >> 14);
1539 return mtrr_state
->fixed_ranges
[idx
];
1540 } else if (start
< 0x1000000) {
1542 idx
+= ((start
- 0xC0000) >> 12);
1543 return mtrr_state
->fixed_ranges
[idx
];
1548 * Look in variable ranges
1549 * Look of multiple ranges matching this address and pick type
1550 * as per MTRR precedence
1552 if (!(mtrr_state
->enabled
& 2))
1553 return mtrr_state
->def_type
;
1556 for (i
= 0; i
< num_var_ranges
; ++i
) {
1557 unsigned short start_state
, end_state
;
1559 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1562 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1563 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1564 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1565 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1567 start_state
= ((start
& mask
) == (base
& mask
));
1568 end_state
= ((end
& mask
) == (base
& mask
));
1569 if (start_state
!= end_state
)
1572 if ((start
& mask
) != (base
& mask
))
1575 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1576 if (prev_match
== 0xFF) {
1577 prev_match
= curr_match
;
1581 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1582 curr_match
== MTRR_TYPE_UNCACHABLE
)
1583 return MTRR_TYPE_UNCACHABLE
;
1585 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1586 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1587 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1588 curr_match
== MTRR_TYPE_WRBACK
)) {
1589 prev_match
= MTRR_TYPE_WRTHROUGH
;
1590 curr_match
= MTRR_TYPE_WRTHROUGH
;
1593 if (prev_match
!= curr_match
)
1594 return MTRR_TYPE_UNCACHABLE
;
1597 if (prev_match
!= 0xFF)
1600 return mtrr_state
->def_type
;
1603 static u8
get_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1607 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1608 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1609 if (mtrr
== 0xfe || mtrr
== 0xff)
1610 mtrr
= MTRR_TYPE_WRBACK
;
1614 static int kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1617 struct hlist_head
*bucket
;
1618 struct kvm_mmu_page
*s
;
1619 struct hlist_node
*node
, *n
;
1621 index
= kvm_page_table_hashfn(sp
->gfn
);
1622 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
1623 /* don't unsync if pagetable is shadowed with multiple roles */
1624 hlist_for_each_entry_safe(s
, node
, n
, bucket
, hash_link
) {
1625 if (s
->gfn
!= sp
->gfn
|| s
->role
.metaphysical
)
1627 if (s
->role
.word
!= sp
->role
.word
)
1630 ++vcpu
->kvm
->stat
.mmu_unsync
;
1634 list_add(&sp
->oos_link
, &vcpu
->kvm
->arch
.oos_global_pages
);
1635 ++vcpu
->kvm
->stat
.mmu_unsync_global
;
1637 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1639 mmu_convert_notrap(sp
);
1643 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1646 struct kvm_mmu_page
*shadow
;
1648 shadow
= kvm_mmu_lookup_page(vcpu
->kvm
, gfn
);
1650 if (shadow
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1654 if (can_unsync
&& oos_shadow
)
1655 return kvm_unsync_page(vcpu
, shadow
);
1661 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1662 unsigned pte_access
, int user_fault
,
1663 int write_fault
, int dirty
, int largepage
,
1664 int global
, gfn_t gfn
, pfn_t pfn
, bool speculative
,
1669 u64 mt_mask
= shadow_mt_mask
;
1670 struct kvm_mmu_page
*sp
= page_header(__pa(shadow_pte
));
1672 if (!(vcpu
->arch
.cr4
& X86_CR4_PGE
))
1674 if (!global
&& sp
->global
) {
1677 kvm_unlink_unsync_global(vcpu
->kvm
, sp
);
1678 kvm_mmu_mark_parents_unsync(vcpu
, sp
);
1683 * We don't set the accessed bit, since we sometimes want to see
1684 * whether the guest actually used the pte (in order to detect
1687 spte
= shadow_base_present_pte
| shadow_dirty_mask
;
1689 spte
|= shadow_accessed_mask
;
1691 pte_access
&= ~ACC_WRITE_MASK
;
1692 if (pte_access
& ACC_EXEC_MASK
)
1693 spte
|= shadow_x_mask
;
1695 spte
|= shadow_nx_mask
;
1696 if (pte_access
& ACC_USER_MASK
)
1697 spte
|= shadow_user_mask
;
1699 spte
|= PT_PAGE_SIZE_MASK
;
1701 mt_mask
= get_memory_type(vcpu
, gfn
) <<
1702 kvm_x86_ops
->get_mt_mask_shift();
1706 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1708 if ((pte_access
& ACC_WRITE_MASK
)
1709 || (write_fault
&& !is_write_protection(vcpu
) && !user_fault
)) {
1711 if (largepage
&& has_wrprotected_page(vcpu
->kvm
, gfn
)) {
1713 spte
= shadow_trap_nonpresent_pte
;
1717 spte
|= PT_WRITABLE_MASK
;
1720 * Optimization: for pte sync, if spte was writable the hash
1721 * lookup is unnecessary (and expensive). Write protection
1722 * is responsibility of mmu_get_page / kvm_sync_page.
1723 * Same reasoning can be applied to dirty page accounting.
1725 if (!can_unsync
&& is_writeble_pte(*shadow_pte
))
1728 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1729 pgprintk("%s: found shadow page for %lx, marking ro\n",
1732 pte_access
&= ~ACC_WRITE_MASK
;
1733 if (is_writeble_pte(spte
))
1734 spte
&= ~PT_WRITABLE_MASK
;
1738 if (pte_access
& ACC_WRITE_MASK
)
1739 mark_page_dirty(vcpu
->kvm
, gfn
);
1742 set_shadow_pte(shadow_pte
, spte
);
1746 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*shadow_pte
,
1747 unsigned pt_access
, unsigned pte_access
,
1748 int user_fault
, int write_fault
, int dirty
,
1749 int *ptwrite
, int largepage
, int global
,
1750 gfn_t gfn
, pfn_t pfn
, bool speculative
)
1752 int was_rmapped
= 0;
1753 int was_writeble
= is_writeble_pte(*shadow_pte
);
1755 pgprintk("%s: spte %llx access %x write_fault %d"
1756 " user_fault %d gfn %lx\n",
1757 __func__
, *shadow_pte
, pt_access
,
1758 write_fault
, user_fault
, gfn
);
1760 if (is_rmap_pte(*shadow_pte
)) {
1762 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
1763 * the parent of the now unreachable PTE.
1765 if (largepage
&& !is_large_pte(*shadow_pte
)) {
1766 struct kvm_mmu_page
*child
;
1767 u64 pte
= *shadow_pte
;
1769 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1770 mmu_page_remove_parent_pte(child
, shadow_pte
);
1771 } else if (pfn
!= spte_to_pfn(*shadow_pte
)) {
1772 pgprintk("hfn old %lx new %lx\n",
1773 spte_to_pfn(*shadow_pte
), pfn
);
1774 rmap_remove(vcpu
->kvm
, shadow_pte
);
1777 was_rmapped
= is_large_pte(*shadow_pte
);
1782 if (set_spte(vcpu
, shadow_pte
, pte_access
, user_fault
, write_fault
,
1783 dirty
, largepage
, global
, gfn
, pfn
, speculative
, true)) {
1786 kvm_x86_ops
->tlb_flush(vcpu
);
1789 pgprintk("%s: setting spte %llx\n", __func__
, *shadow_pte
);
1790 pgprintk("instantiating %s PTE (%s) at %ld (%llx) addr %p\n",
1791 is_large_pte(*shadow_pte
)? "2MB" : "4kB",
1792 is_present_pte(*shadow_pte
)?"RW":"R", gfn
,
1793 *shadow_pte
, shadow_pte
);
1794 if (!was_rmapped
&& is_large_pte(*shadow_pte
))
1795 ++vcpu
->kvm
->stat
.lpages
;
1797 page_header_update_slot(vcpu
->kvm
, shadow_pte
, gfn
);
1799 rmap_add(vcpu
, shadow_pte
, gfn
, largepage
);
1800 if (!is_rmap_pte(*shadow_pte
))
1801 kvm_release_pfn_clean(pfn
);
1804 kvm_release_pfn_dirty(pfn
);
1806 kvm_release_pfn_clean(pfn
);
1809 vcpu
->arch
.last_pte_updated
= shadow_pte
;
1810 vcpu
->arch
.last_pte_gfn
= gfn
;
1814 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
1818 struct direct_shadow_walk
{
1819 struct kvm_shadow_walk walker
;
1826 static int direct_map_entry(struct kvm_shadow_walk
*_walk
,
1827 struct kvm_vcpu
*vcpu
,
1828 u64 addr
, u64
*sptep
, int level
)
1830 struct direct_shadow_walk
*walk
=
1831 container_of(_walk
, struct direct_shadow_walk
, walker
);
1832 struct kvm_mmu_page
*sp
;
1834 gfn_t gfn
= addr
>> PAGE_SHIFT
;
1836 if (level
== PT_PAGE_TABLE_LEVEL
1837 || (walk
->largepage
&& level
== PT_DIRECTORY_LEVEL
)) {
1838 mmu_set_spte(vcpu
, sptep
, ACC_ALL
, ACC_ALL
,
1839 0, walk
->write
, 1, &walk
->pt_write
,
1840 walk
->largepage
, 0, gfn
, walk
->pfn
, false);
1841 ++vcpu
->stat
.pf_fixed
;
1845 if (*sptep
== shadow_trap_nonpresent_pte
) {
1846 pseudo_gfn
= (addr
& PT64_DIR_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
1847 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, (gva_t
)addr
, level
- 1,
1850 pgprintk("nonpaging_map: ENOMEM\n");
1851 kvm_release_pfn_clean(walk
->pfn
);
1855 set_shadow_pte(sptep
,
1857 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
1858 | shadow_user_mask
| shadow_x_mask
);
1863 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
1864 int largepage
, gfn_t gfn
, pfn_t pfn
)
1867 struct direct_shadow_walk walker
= {
1868 .walker
= { .entry
= direct_map_entry
, },
1870 .largepage
= largepage
,
1875 r
= walk_shadow(&walker
.walker
, vcpu
, gfn
<< PAGE_SHIFT
);
1878 return walker
.pt_write
;
1881 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
)
1886 unsigned long mmu_seq
;
1888 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
1889 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
1893 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
1895 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
1898 if (is_error_pfn(pfn
)) {
1899 kvm_release_pfn_clean(pfn
);
1903 spin_lock(&vcpu
->kvm
->mmu_lock
);
1904 if (mmu_notifier_retry(vcpu
, mmu_seq
))
1906 kvm_mmu_free_some_pages(vcpu
);
1907 r
= __direct_map(vcpu
, v
, write
, largepage
, gfn
, pfn
);
1908 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1914 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1915 kvm_release_pfn_clean(pfn
);
1920 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
1923 struct kvm_mmu_page
*sp
;
1925 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
1927 spin_lock(&vcpu
->kvm
->mmu_lock
);
1928 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1929 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1931 sp
= page_header(root
);
1933 if (!sp
->root_count
&& sp
->role
.invalid
)
1934 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1935 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1936 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1939 for (i
= 0; i
< 4; ++i
) {
1940 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1943 root
&= PT64_BASE_ADDR_MASK
;
1944 sp
= page_header(root
);
1946 if (!sp
->root_count
&& sp
->role
.invalid
)
1947 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
1949 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
1951 spin_unlock(&vcpu
->kvm
->mmu_lock
);
1952 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
1955 static void mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
1959 struct kvm_mmu_page
*sp
;
1960 int metaphysical
= 0;
1962 root_gfn
= vcpu
->arch
.cr3
>> PAGE_SHIFT
;
1964 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
1965 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
1967 ASSERT(!VALID_PAGE(root
));
1970 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0,
1971 PT64_ROOT_LEVEL
, metaphysical
,
1973 root
= __pa(sp
->spt
);
1975 vcpu
->arch
.mmu
.root_hpa
= root
;
1978 metaphysical
= !is_paging(vcpu
);
1981 for (i
= 0; i
< 4; ++i
) {
1982 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
1984 ASSERT(!VALID_PAGE(root
));
1985 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
1986 if (!is_present_pte(vcpu
->arch
.pdptrs
[i
])) {
1987 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
1990 root_gfn
= vcpu
->arch
.pdptrs
[i
] >> PAGE_SHIFT
;
1991 } else if (vcpu
->arch
.mmu
.root_level
== 0)
1993 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
1994 PT32_ROOT_LEVEL
, metaphysical
,
1996 root
= __pa(sp
->spt
);
1998 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
2000 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
2003 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2006 struct kvm_mmu_page
*sp
;
2008 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2010 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2011 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2012 sp
= page_header(root
);
2013 mmu_sync_children(vcpu
, sp
);
2016 for (i
= 0; i
< 4; ++i
) {
2017 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2020 root
&= PT64_BASE_ADDR_MASK
;
2021 sp
= page_header(root
);
2022 mmu_sync_children(vcpu
, sp
);
2027 static void mmu_sync_global(struct kvm_vcpu
*vcpu
)
2029 struct kvm
*kvm
= vcpu
->kvm
;
2030 struct kvm_mmu_page
*sp
, *n
;
2032 list_for_each_entry_safe(sp
, n
, &kvm
->arch
.oos_global_pages
, oos_link
)
2033 kvm_sync_page(vcpu
, sp
);
2036 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2038 spin_lock(&vcpu
->kvm
->mmu_lock
);
2039 mmu_sync_roots(vcpu
);
2040 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2043 void kvm_mmu_sync_global(struct kvm_vcpu
*vcpu
)
2045 spin_lock(&vcpu
->kvm
->mmu_lock
);
2046 mmu_sync_global(vcpu
);
2047 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2050 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
)
2055 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
2061 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
2062 r
= mmu_topup_memory_caches(vcpu
);
2067 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2069 gfn
= gva
>> PAGE_SHIFT
;
2071 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
2072 error_code
& PFERR_WRITE_MASK
, gfn
);
2075 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
,
2081 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2082 unsigned long mmu_seq
;
2085 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2087 r
= mmu_topup_memory_caches(vcpu
);
2091 if (is_largepage_backed(vcpu
, gfn
& ~(KVM_PAGES_PER_HPAGE
-1))) {
2092 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2095 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2097 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2098 if (is_error_pfn(pfn
)) {
2099 kvm_release_pfn_clean(pfn
);
2102 spin_lock(&vcpu
->kvm
->mmu_lock
);
2103 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2105 kvm_mmu_free_some_pages(vcpu
);
2106 r
= __direct_map(vcpu
, gpa
, error_code
& PFERR_WRITE_MASK
,
2107 largepage
, gfn
, pfn
);
2108 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2113 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2114 kvm_release_pfn_clean(pfn
);
2118 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
2120 mmu_free_roots(vcpu
);
2123 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
)
2125 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2127 context
->new_cr3
= nonpaging_new_cr3
;
2128 context
->page_fault
= nonpaging_page_fault
;
2129 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2130 context
->free
= nonpaging_free
;
2131 context
->prefetch_page
= nonpaging_prefetch_page
;
2132 context
->sync_page
= nonpaging_sync_page
;
2133 context
->invlpg
= nonpaging_invlpg
;
2134 context
->root_level
= 0;
2135 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2136 context
->root_hpa
= INVALID_PAGE
;
2140 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2142 ++vcpu
->stat
.tlb_flush
;
2143 kvm_x86_ops
->tlb_flush(vcpu
);
2146 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2148 pgprintk("%s: cr3 %lx\n", __func__
, vcpu
->arch
.cr3
);
2149 mmu_free_roots(vcpu
);
2152 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2156 kvm_inject_page_fault(vcpu
, addr
, err_code
);
2159 static void paging_free(struct kvm_vcpu
*vcpu
)
2161 nonpaging_free(vcpu
);
2165 #include "paging_tmpl.h"
2169 #include "paging_tmpl.h"
2172 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
, int level
)
2174 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2176 ASSERT(is_pae(vcpu
));
2177 context
->new_cr3
= paging_new_cr3
;
2178 context
->page_fault
= paging64_page_fault
;
2179 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2180 context
->prefetch_page
= paging64_prefetch_page
;
2181 context
->sync_page
= paging64_sync_page
;
2182 context
->invlpg
= paging64_invlpg
;
2183 context
->free
= paging_free
;
2184 context
->root_level
= level
;
2185 context
->shadow_root_level
= level
;
2186 context
->root_hpa
= INVALID_PAGE
;
2190 static int paging64_init_context(struct kvm_vcpu
*vcpu
)
2192 return paging64_init_context_common(vcpu
, PT64_ROOT_LEVEL
);
2195 static int paging32_init_context(struct kvm_vcpu
*vcpu
)
2197 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2199 context
->new_cr3
= paging_new_cr3
;
2200 context
->page_fault
= paging32_page_fault
;
2201 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2202 context
->free
= paging_free
;
2203 context
->prefetch_page
= paging32_prefetch_page
;
2204 context
->sync_page
= paging32_sync_page
;
2205 context
->invlpg
= paging32_invlpg
;
2206 context
->root_level
= PT32_ROOT_LEVEL
;
2207 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2208 context
->root_hpa
= INVALID_PAGE
;
2212 static int paging32E_init_context(struct kvm_vcpu
*vcpu
)
2214 return paging64_init_context_common(vcpu
, PT32E_ROOT_LEVEL
);
2217 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2219 struct kvm_mmu
*context
= &vcpu
->arch
.mmu
;
2221 context
->new_cr3
= nonpaging_new_cr3
;
2222 context
->page_fault
= tdp_page_fault
;
2223 context
->free
= nonpaging_free
;
2224 context
->prefetch_page
= nonpaging_prefetch_page
;
2225 context
->sync_page
= nonpaging_sync_page
;
2226 context
->invlpg
= nonpaging_invlpg
;
2227 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2228 context
->root_hpa
= INVALID_PAGE
;
2230 if (!is_paging(vcpu
)) {
2231 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2232 context
->root_level
= 0;
2233 } else if (is_long_mode(vcpu
)) {
2234 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2235 context
->root_level
= PT64_ROOT_LEVEL
;
2236 } else if (is_pae(vcpu
)) {
2237 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2238 context
->root_level
= PT32E_ROOT_LEVEL
;
2240 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2241 context
->root_level
= PT32_ROOT_LEVEL
;
2247 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2250 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2252 if (!is_paging(vcpu
))
2253 return nonpaging_init_context(vcpu
);
2254 else if (is_long_mode(vcpu
))
2255 return paging64_init_context(vcpu
);
2256 else if (is_pae(vcpu
))
2257 return paging32E_init_context(vcpu
);
2259 return paging32_init_context(vcpu
);
2262 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
2264 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2267 return init_kvm_tdp_mmu(vcpu
);
2269 return init_kvm_softmmu(vcpu
);
2272 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
2275 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
)) {
2276 vcpu
->arch
.mmu
.free(vcpu
);
2277 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2281 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
2283 destroy_kvm_mmu(vcpu
);
2284 return init_kvm_mmu(vcpu
);
2286 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
2288 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
2292 r
= mmu_topup_memory_caches(vcpu
);
2295 spin_lock(&vcpu
->kvm
->mmu_lock
);
2296 kvm_mmu_free_some_pages(vcpu
);
2297 mmu_alloc_roots(vcpu
);
2298 mmu_sync_roots(vcpu
);
2299 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2300 kvm_x86_ops
->set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
2301 kvm_mmu_flush_tlb(vcpu
);
2305 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
2307 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
2309 mmu_free_roots(vcpu
);
2312 static void mmu_pte_write_zap_pte(struct kvm_vcpu
*vcpu
,
2313 struct kvm_mmu_page
*sp
,
2317 struct kvm_mmu_page
*child
;
2320 if (is_shadow_present_pte(pte
)) {
2321 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
||
2323 rmap_remove(vcpu
->kvm
, spte
);
2325 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2326 mmu_page_remove_parent_pte(child
, spte
);
2329 set_shadow_pte(spte
, shadow_trap_nonpresent_pte
);
2330 if (is_large_pte(pte
))
2331 --vcpu
->kvm
->stat
.lpages
;
2334 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
2335 struct kvm_mmu_page
*sp
,
2339 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
2340 if (!vcpu
->arch
.update_pte
.largepage
||
2341 sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2342 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
2347 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
2348 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
)
2349 paging32_update_pte(vcpu
, sp
, spte
, new);
2351 paging64_update_pte(vcpu
, sp
, spte
, new);
2354 static bool need_remote_flush(u64 old
, u64
new)
2356 if (!is_shadow_present_pte(old
))
2358 if (!is_shadow_present_pte(new))
2360 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
2362 old
^= PT64_NX_MASK
;
2363 new ^= PT64_NX_MASK
;
2364 return (old
& ~new & PT64_PERM_MASK
) != 0;
2367 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, u64 old
, u64
new)
2369 if (need_remote_flush(old
, new))
2370 kvm_flush_remote_tlbs(vcpu
->kvm
);
2372 kvm_mmu_flush_tlb(vcpu
);
2375 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
2377 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2379 return !!(spte
&& (*spte
& shadow_accessed_mask
));
2382 static void mmu_guess_page_from_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2383 const u8
*new, int bytes
)
2390 vcpu
->arch
.update_pte
.largepage
= 0;
2392 if (bytes
!= 4 && bytes
!= 8)
2396 * Assume that the pte write on a page table of the same type
2397 * as the current vcpu paging mode. This is nearly always true
2398 * (might be false while changing modes). Note it is verified later
2402 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
2403 if ((bytes
== 4) && (gpa
% 4 == 0)) {
2404 r
= kvm_read_guest(vcpu
->kvm
, gpa
& ~(u64
)7, &gpte
, 8);
2407 memcpy((void *)&gpte
+ (gpa
% 8), new, 4);
2408 } else if ((bytes
== 8) && (gpa
% 8 == 0)) {
2409 memcpy((void *)&gpte
, new, 8);
2412 if ((bytes
== 4) && (gpa
% 4 == 0))
2413 memcpy((void *)&gpte
, new, 4);
2415 if (!is_present_pte(gpte
))
2417 gfn
= (gpte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
2419 if (is_large_pte(gpte
) && is_largepage_backed(vcpu
, gfn
)) {
2420 gfn
&= ~(KVM_PAGES_PER_HPAGE
-1);
2421 vcpu
->arch
.update_pte
.largepage
= 1;
2423 vcpu
->arch
.update_pte
.mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2425 pfn
= gfn_to_pfn(vcpu
->kvm
, gfn
);
2427 if (is_error_pfn(pfn
)) {
2428 kvm_release_pfn_clean(pfn
);
2431 vcpu
->arch
.update_pte
.gfn
= gfn
;
2432 vcpu
->arch
.update_pte
.pfn
= pfn
;
2435 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
2437 u64
*spte
= vcpu
->arch
.last_pte_updated
;
2440 && vcpu
->arch
.last_pte_gfn
== gfn
2441 && shadow_accessed_mask
2442 && !(*spte
& shadow_accessed_mask
)
2443 && is_shadow_present_pte(*spte
))
2444 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
2447 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
2448 const u8
*new, int bytes
,
2449 bool guest_initiated
)
2451 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2452 struct kvm_mmu_page
*sp
;
2453 struct hlist_node
*node
, *n
;
2454 struct hlist_head
*bucket
;
2458 unsigned offset
= offset_in_page(gpa
);
2460 unsigned page_offset
;
2461 unsigned misaligned
;
2468 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
2469 mmu_guess_page_from_pte_write(vcpu
, gpa
, new, bytes
);
2470 spin_lock(&vcpu
->kvm
->mmu_lock
);
2471 kvm_mmu_access_page(vcpu
, gfn
);
2472 kvm_mmu_free_some_pages(vcpu
);
2473 ++vcpu
->kvm
->stat
.mmu_pte_write
;
2474 kvm_mmu_audit(vcpu
, "pre pte write");
2475 if (guest_initiated
) {
2476 if (gfn
== vcpu
->arch
.last_pt_write_gfn
2477 && !last_updated_pte_accessed(vcpu
)) {
2478 ++vcpu
->arch
.last_pt_write_count
;
2479 if (vcpu
->arch
.last_pt_write_count
>= 3)
2482 vcpu
->arch
.last_pt_write_gfn
= gfn
;
2483 vcpu
->arch
.last_pt_write_count
= 1;
2484 vcpu
->arch
.last_pte_updated
= NULL
;
2487 index
= kvm_page_table_hashfn(gfn
);
2488 bucket
= &vcpu
->kvm
->arch
.mmu_page_hash
[index
];
2489 hlist_for_each_entry_safe(sp
, node
, n
, bucket
, hash_link
) {
2490 if (sp
->gfn
!= gfn
|| sp
->role
.metaphysical
|| sp
->role
.invalid
)
2492 pte_size
= sp
->role
.glevels
== PT32_ROOT_LEVEL
? 4 : 8;
2493 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
2494 misaligned
|= bytes
< 4;
2495 if (misaligned
|| flooded
) {
2497 * Misaligned accesses are too much trouble to fix
2498 * up; also, they usually indicate a page is not used
2501 * If we're seeing too many writes to a page,
2502 * it may no longer be a page table, or we may be
2503 * forking, in which case it is better to unmap the
2506 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
2507 gpa
, bytes
, sp
->role
.word
);
2508 if (kvm_mmu_zap_page(vcpu
->kvm
, sp
))
2510 ++vcpu
->kvm
->stat
.mmu_flooded
;
2513 page_offset
= offset
;
2514 level
= sp
->role
.level
;
2516 if (sp
->role
.glevels
== PT32_ROOT_LEVEL
) {
2517 page_offset
<<= 1; /* 32->64 */
2519 * A 32-bit pde maps 4MB while the shadow pdes map
2520 * only 2MB. So we need to double the offset again
2521 * and zap two pdes instead of one.
2523 if (level
== PT32_ROOT_LEVEL
) {
2524 page_offset
&= ~7; /* kill rounding error */
2528 quadrant
= page_offset
>> PAGE_SHIFT
;
2529 page_offset
&= ~PAGE_MASK
;
2530 if (quadrant
!= sp
->role
.quadrant
)
2533 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
2534 if ((gpa
& (pte_size
- 1)) || (bytes
< pte_size
)) {
2536 r
= kvm_read_guest_atomic(vcpu
->kvm
,
2537 gpa
& ~(u64
)(pte_size
- 1),
2539 new = (const void *)&gentry
;
2545 mmu_pte_write_zap_pte(vcpu
, sp
, spte
);
2547 mmu_pte_write_new_pte(vcpu
, sp
, spte
, new);
2548 mmu_pte_write_flush_tlb(vcpu
, entry
, *spte
);
2552 kvm_mmu_audit(vcpu
, "post pte write");
2553 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2554 if (!is_error_pfn(vcpu
->arch
.update_pte
.pfn
)) {
2555 kvm_release_pfn_clean(vcpu
->arch
.update_pte
.pfn
);
2556 vcpu
->arch
.update_pte
.pfn
= bad_pfn
;
2560 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
2565 gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, gva
);
2567 spin_lock(&vcpu
->kvm
->mmu_lock
);
2568 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
2569 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2572 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
2574 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
2576 while (vcpu
->kvm
->arch
.n_free_mmu_pages
< KVM_REFILL_PAGES
) {
2577 struct kvm_mmu_page
*sp
;
2579 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
2580 struct kvm_mmu_page
, link
);
2581 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2582 ++vcpu
->kvm
->stat
.mmu_recycled
;
2586 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
)
2589 enum emulation_result er
;
2591 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
);
2600 r
= mmu_topup_memory_caches(vcpu
);
2604 er
= emulate_instruction(vcpu
, vcpu
->run
, cr2
, error_code
, 0);
2609 case EMULATE_DO_MMIO
:
2610 ++vcpu
->stat
.mmio_exits
;
2613 kvm_report_emulation_failure(vcpu
, "pagetable");
2621 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
2623 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
2625 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
2626 kvm_mmu_flush_tlb(vcpu
);
2627 ++vcpu
->stat
.invlpg
;
2629 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
2631 void kvm_enable_tdp(void)
2635 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
2637 void kvm_disable_tdp(void)
2639 tdp_enabled
= false;
2641 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
2643 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
2645 struct kvm_mmu_page
*sp
;
2647 while (!list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
2648 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.next
,
2649 struct kvm_mmu_page
, link
);
2650 kvm_mmu_zap_page(vcpu
->kvm
, sp
);
2653 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
2656 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
2663 if (vcpu
->kvm
->arch
.n_requested_mmu_pages
)
2664 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2665 vcpu
->kvm
->arch
.n_requested_mmu_pages
;
2667 vcpu
->kvm
->arch
.n_free_mmu_pages
=
2668 vcpu
->kvm
->arch
.n_alloc_mmu_pages
;
2670 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
2671 * Therefore we need to allocate shadow page tables in the first
2672 * 4GB of memory, which happens to fit the DMA32 zone.
2674 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
2677 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
2678 for (i
= 0; i
< 4; ++i
)
2679 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2684 free_mmu_pages(vcpu
);
2688 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
2691 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2693 return alloc_mmu_pages(vcpu
);
2696 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
2699 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2701 return init_kvm_mmu(vcpu
);
2704 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
2708 destroy_kvm_mmu(vcpu
);
2709 free_mmu_pages(vcpu
);
2710 mmu_free_memory_caches(vcpu
);
2713 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
2715 struct kvm_mmu_page
*sp
;
2717 spin_lock(&kvm
->mmu_lock
);
2718 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
2722 if (!test_bit(slot
, sp
->slot_bitmap
))
2726 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
2728 if (pt
[i
] & PT_WRITABLE_MASK
)
2729 pt
[i
] &= ~PT_WRITABLE_MASK
;
2731 kvm_flush_remote_tlbs(kvm
);
2732 spin_unlock(&kvm
->mmu_lock
);
2735 void kvm_mmu_zap_all(struct kvm
*kvm
)
2737 struct kvm_mmu_page
*sp
, *node
;
2739 spin_lock(&kvm
->mmu_lock
);
2740 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
2741 if (kvm_mmu_zap_page(kvm
, sp
))
2742 node
= container_of(kvm
->arch
.active_mmu_pages
.next
,
2743 struct kvm_mmu_page
, link
);
2744 spin_unlock(&kvm
->mmu_lock
);
2746 kvm_flush_remote_tlbs(kvm
);
2749 static void kvm_mmu_remove_one_alloc_mmu_page(struct kvm
*kvm
)
2751 struct kvm_mmu_page
*page
;
2753 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
2754 struct kvm_mmu_page
, link
);
2755 kvm_mmu_zap_page(kvm
, page
);
2758 static int mmu_shrink(int nr_to_scan
, gfp_t gfp_mask
)
2761 struct kvm
*kvm_freed
= NULL
;
2762 int cache_count
= 0;
2764 spin_lock(&kvm_lock
);
2766 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
2769 if (!down_read_trylock(&kvm
->slots_lock
))
2771 spin_lock(&kvm
->mmu_lock
);
2772 npages
= kvm
->arch
.n_alloc_mmu_pages
-
2773 kvm
->arch
.n_free_mmu_pages
;
2774 cache_count
+= npages
;
2775 if (!kvm_freed
&& nr_to_scan
> 0 && npages
> 0) {
2776 kvm_mmu_remove_one_alloc_mmu_page(kvm
);
2782 spin_unlock(&kvm
->mmu_lock
);
2783 up_read(&kvm
->slots_lock
);
2786 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
2788 spin_unlock(&kvm_lock
);
2793 static struct shrinker mmu_shrinker
= {
2794 .shrink
= mmu_shrink
,
2795 .seeks
= DEFAULT_SEEKS
* 10,
2798 static void mmu_destroy_caches(void)
2800 if (pte_chain_cache
)
2801 kmem_cache_destroy(pte_chain_cache
);
2802 if (rmap_desc_cache
)
2803 kmem_cache_destroy(rmap_desc_cache
);
2804 if (mmu_page_header_cache
)
2805 kmem_cache_destroy(mmu_page_header_cache
);
2808 void kvm_mmu_module_exit(void)
2810 mmu_destroy_caches();
2811 unregister_shrinker(&mmu_shrinker
);
2814 int kvm_mmu_module_init(void)
2816 pte_chain_cache
= kmem_cache_create("kvm_pte_chain",
2817 sizeof(struct kvm_pte_chain
),
2819 if (!pte_chain_cache
)
2821 rmap_desc_cache
= kmem_cache_create("kvm_rmap_desc",
2822 sizeof(struct kvm_rmap_desc
),
2824 if (!rmap_desc_cache
)
2827 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
2828 sizeof(struct kvm_mmu_page
),
2830 if (!mmu_page_header_cache
)
2833 register_shrinker(&mmu_shrinker
);
2838 mmu_destroy_caches();
2843 * Caculate mmu pages needed for kvm.
2845 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
2848 unsigned int nr_mmu_pages
;
2849 unsigned int nr_pages
= 0;
2851 for (i
= 0; i
< kvm
->nmemslots
; i
++)
2852 nr_pages
+= kvm
->memslots
[i
].npages
;
2854 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
2855 nr_mmu_pages
= max(nr_mmu_pages
,
2856 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
2858 return nr_mmu_pages
;
2861 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2864 if (len
> buffer
->len
)
2869 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
2874 ret
= pv_mmu_peek_buffer(buffer
, len
);
2879 buffer
->processed
+= len
;
2883 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
2884 gpa_t addr
, gpa_t value
)
2889 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
2892 r
= mmu_topup_memory_caches(vcpu
);
2896 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
2902 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2904 kvm_x86_ops
->tlb_flush(vcpu
);
2905 set_bit(KVM_REQ_MMU_SYNC
, &vcpu
->requests
);
2909 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
2911 spin_lock(&vcpu
->kvm
->mmu_lock
);
2912 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
2913 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2917 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
2918 struct kvm_pv_mmu_op_buffer
*buffer
)
2920 struct kvm_mmu_op_header
*header
;
2922 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
2925 switch (header
->op
) {
2926 case KVM_MMU_OP_WRITE_PTE
: {
2927 struct kvm_mmu_op_write_pte
*wpte
;
2929 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
2932 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
2935 case KVM_MMU_OP_FLUSH_TLB
: {
2936 struct kvm_mmu_op_flush_tlb
*ftlb
;
2938 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
2941 return kvm_pv_mmu_flush_tlb(vcpu
);
2943 case KVM_MMU_OP_RELEASE_PT
: {
2944 struct kvm_mmu_op_release_pt
*rpt
;
2946 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
2949 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
2955 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
2956 gpa_t addr
, unsigned long *ret
)
2959 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
2961 buffer
->ptr
= buffer
->buf
;
2962 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
2963 buffer
->processed
= 0;
2965 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
2969 while (buffer
->len
) {
2970 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
2979 *ret
= buffer
->processed
;
2985 static const char *audit_msg
;
2987 static gva_t
canonicalize(gva_t gva
)
2989 #ifdef CONFIG_X86_64
2990 gva
= (long long)(gva
<< 16) >> 16;
2995 static void audit_mappings_page(struct kvm_vcpu
*vcpu
, u64 page_pte
,
2996 gva_t va
, int level
)
2998 u64
*pt
= __va(page_pte
& PT64_BASE_ADDR_MASK
);
3000 gva_t va_delta
= 1ul << (PAGE_SHIFT
+ 9 * (level
- 1));
3002 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
, va
+= va_delta
) {
3005 if (ent
== shadow_trap_nonpresent_pte
)
3008 va
= canonicalize(va
);
3010 if (ent
== shadow_notrap_nonpresent_pte
)
3011 printk(KERN_ERR
"audit: (%s) nontrapping pte"
3012 " in nonleaf level: levels %d gva %lx"
3013 " level %d pte %llx\n", audit_msg
,
3014 vcpu
->arch
.mmu
.root_level
, va
, level
, ent
);
3016 audit_mappings_page(vcpu
, ent
, va
, level
- 1);
3018 gpa_t gpa
= vcpu
->arch
.mmu
.gva_to_gpa(vcpu
, va
);
3019 hpa_t hpa
= (hpa_t
)gpa_to_pfn(vcpu
, gpa
) << PAGE_SHIFT
;
3021 if (is_shadow_present_pte(ent
)
3022 && (ent
& PT64_BASE_ADDR_MASK
) != hpa
)
3023 printk(KERN_ERR
"xx audit error: (%s) levels %d"
3024 " gva %lx gpa %llx hpa %llx ent %llx %d\n",
3025 audit_msg
, vcpu
->arch
.mmu
.root_level
,
3027 is_shadow_present_pte(ent
));
3028 else if (ent
== shadow_notrap_nonpresent_pte
3029 && !is_error_hpa(hpa
))
3030 printk(KERN_ERR
"audit: (%s) notrap shadow,"
3031 " valid guest gva %lx\n", audit_msg
, va
);
3032 kvm_release_pfn_clean(pfn
);
3038 static void audit_mappings(struct kvm_vcpu
*vcpu
)
3042 if (vcpu
->arch
.mmu
.root_level
== 4)
3043 audit_mappings_page(vcpu
, vcpu
->arch
.mmu
.root_hpa
, 0, 4);
3045 for (i
= 0; i
< 4; ++i
)
3046 if (vcpu
->arch
.mmu
.pae_root
[i
] & PT_PRESENT_MASK
)
3047 audit_mappings_page(vcpu
,
3048 vcpu
->arch
.mmu
.pae_root
[i
],
3053 static int count_rmaps(struct kvm_vcpu
*vcpu
)
3058 for (i
= 0; i
< KVM_MEMORY_SLOTS
; ++i
) {
3059 struct kvm_memory_slot
*m
= &vcpu
->kvm
->memslots
[i
];
3060 struct kvm_rmap_desc
*d
;
3062 for (j
= 0; j
< m
->npages
; ++j
) {
3063 unsigned long *rmapp
= &m
->rmap
[j
];
3067 if (!(*rmapp
& 1)) {
3071 d
= (struct kvm_rmap_desc
*)(*rmapp
& ~1ul);
3073 for (k
= 0; k
< RMAP_EXT
; ++k
)
3074 if (d
->shadow_ptes
[k
])
3085 static int count_writable_mappings(struct kvm_vcpu
*vcpu
)
3088 struct kvm_mmu_page
*sp
;
3091 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3094 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
3097 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3100 if (!(ent
& PT_PRESENT_MASK
))
3102 if (!(ent
& PT_WRITABLE_MASK
))
3110 static void audit_rmap(struct kvm_vcpu
*vcpu
)
3112 int n_rmap
= count_rmaps(vcpu
);
3113 int n_actual
= count_writable_mappings(vcpu
);
3115 if (n_rmap
!= n_actual
)
3116 printk(KERN_ERR
"%s: (%s) rmap %d actual %d\n",
3117 __func__
, audit_msg
, n_rmap
, n_actual
);
3120 static void audit_write_protection(struct kvm_vcpu
*vcpu
)
3122 struct kvm_mmu_page
*sp
;
3123 struct kvm_memory_slot
*slot
;
3124 unsigned long *rmapp
;
3127 list_for_each_entry(sp
, &vcpu
->kvm
->arch
.active_mmu_pages
, link
) {
3128 if (sp
->role
.metaphysical
)
3131 gfn
= unalias_gfn(vcpu
->kvm
, sp
->gfn
);
3132 slot
= gfn_to_memslot_unaliased(vcpu
->kvm
, sp
->gfn
);
3133 rmapp
= &slot
->rmap
[gfn
- slot
->base_gfn
];
3135 printk(KERN_ERR
"%s: (%s) shadow page has writable"
3136 " mappings: gfn %lx role %x\n",
3137 __func__
, audit_msg
, sp
->gfn
,
3142 static void kvm_mmu_audit(struct kvm_vcpu
*vcpu
, const char *msg
)
3149 audit_write_protection(vcpu
);
3150 audit_mappings(vcpu
);