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.
10 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
13 * Yaniv Kamay <yaniv@qumranet.com>
14 * Avi Kivity <avi@qumranet.com>
16 * This work is licensed under the terms of the GNU GPL, version 2. See
17 * the COPYING file in the top-level directory.
24 #include "kvm_cache_regs.h"
27 #include <linux/kvm_host.h>
28 #include <linux/types.h>
29 #include <linux/string.h>
31 #include <linux/highmem.h>
32 #include <linux/module.h>
33 #include <linux/swap.h>
34 #include <linux/hugetlb.h>
35 #include <linux/compiler.h>
36 #include <linux/srcu.h>
37 #include <linux/slab.h>
38 #include <linux/uaccess.h>
41 #include <asm/cmpxchg.h>
46 * When setting this variable to true it enables Two-Dimensional-Paging
47 * where the hardware walks 2 page tables:
48 * 1. the guest-virtual to guest-physical
49 * 2. while doing 1. it walks guest-physical to host-physical
50 * If the hardware supports that we don't need to do shadow paging.
52 bool tdp_enabled
= false;
56 AUDIT_POST_PAGE_FAULT
,
63 char *audit_point_name
[] = {
76 #define pgprintk(x...) do { if (dbg) printk(x); } while (0)
77 #define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
81 #define pgprintk(x...) do { } while (0)
82 #define rmap_printk(x...) do { } while (0)
88 module_param(dbg
, bool, 0644);
91 static int oos_shadow
= 1;
92 module_param(oos_shadow
, bool, 0644);
95 #define ASSERT(x) do { } while (0)
99 printk(KERN_WARNING "assertion failed %s:%d: %s\n", \
100 __FILE__, __LINE__, #x); \
104 #define PTE_PREFETCH_NUM 8
106 #define PT_FIRST_AVAIL_BITS_SHIFT 9
107 #define PT64_SECOND_AVAIL_BITS_SHIFT 52
109 #define PT64_LEVEL_BITS 9
111 #define PT64_LEVEL_SHIFT(level) \
112 (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS)
114 #define PT64_INDEX(address, level)\
115 (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1))
118 #define PT32_LEVEL_BITS 10
120 #define PT32_LEVEL_SHIFT(level) \
121 (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS)
123 #define PT32_LVL_OFFSET_MASK(level) \
124 (PT32_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \
125 * PT32_LEVEL_BITS))) - 1))
127 #define PT32_INDEX(address, level)\
128 (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1))
131 #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
132 #define PT64_DIR_BASE_ADDR_MASK \
133 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1))
134 #define PT64_LVL_ADDR_MASK(level) \
135 (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \
136 * PT64_LEVEL_BITS))) - 1))
137 #define PT64_LVL_OFFSET_MASK(level) \
138 (PT64_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \
139 * PT64_LEVEL_BITS))) - 1))
141 #define PT32_BASE_ADDR_MASK PAGE_MASK
142 #define PT32_DIR_BASE_ADDR_MASK \
143 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1))
144 #define PT32_LVL_ADDR_MASK(level) \
145 (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \
146 * PT32_LEVEL_BITS))) - 1))
148 #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \
151 #define PTE_LIST_EXT 4
153 #define ACC_EXEC_MASK 1
154 #define ACC_WRITE_MASK PT_WRITABLE_MASK
155 #define ACC_USER_MASK PT_USER_MASK
156 #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
158 #include <trace/events/kvm.h>
160 #define CREATE_TRACE_POINTS
161 #include "mmutrace.h"
163 #define SPTE_HOST_WRITEABLE (1ULL << PT_FIRST_AVAIL_BITS_SHIFT)
165 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
167 struct pte_list_desc
{
168 u64
*sptes
[PTE_LIST_EXT
];
169 struct pte_list_desc
*more
;
172 struct kvm_shadow_walk_iterator
{
180 #define for_each_shadow_entry(_vcpu, _addr, _walker) \
181 for (shadow_walk_init(&(_walker), _vcpu, _addr); \
182 shadow_walk_okay(&(_walker)); \
183 shadow_walk_next(&(_walker)))
185 static struct kmem_cache
*pte_list_desc_cache
;
186 static struct kmem_cache
*mmu_page_header_cache
;
187 static struct percpu_counter kvm_total_used_mmu_pages
;
189 static u64 __read_mostly shadow_trap_nonpresent_pte
;
190 static u64 __read_mostly shadow_notrap_nonpresent_pte
;
191 static u64 __read_mostly shadow_nx_mask
;
192 static u64 __read_mostly shadow_x_mask
; /* mutual exclusive with nx_mask */
193 static u64 __read_mostly shadow_user_mask
;
194 static u64 __read_mostly shadow_accessed_mask
;
195 static u64 __read_mostly shadow_dirty_mask
;
197 static inline u64
rsvd_bits(int s
, int e
)
199 return ((1ULL << (e
- s
+ 1)) - 1) << s
;
202 void kvm_mmu_set_nonpresent_ptes(u64 trap_pte
, u64 notrap_pte
)
204 shadow_trap_nonpresent_pte
= trap_pte
;
205 shadow_notrap_nonpresent_pte
= notrap_pte
;
207 EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes
);
209 void kvm_mmu_set_mask_ptes(u64 user_mask
, u64 accessed_mask
,
210 u64 dirty_mask
, u64 nx_mask
, u64 x_mask
)
212 shadow_user_mask
= user_mask
;
213 shadow_accessed_mask
= accessed_mask
;
214 shadow_dirty_mask
= dirty_mask
;
215 shadow_nx_mask
= nx_mask
;
216 shadow_x_mask
= x_mask
;
218 EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes
);
220 static int is_cpuid_PSE36(void)
225 static int is_nx(struct kvm_vcpu
*vcpu
)
227 return vcpu
->arch
.efer
& EFER_NX
;
230 static int is_shadow_present_pte(u64 pte
)
232 return pte
!= shadow_trap_nonpresent_pte
233 && pte
!= shadow_notrap_nonpresent_pte
;
236 static int is_large_pte(u64 pte
)
238 return pte
& PT_PAGE_SIZE_MASK
;
241 static int is_dirty_gpte(unsigned long pte
)
243 return pte
& PT_DIRTY_MASK
;
246 static int is_rmap_spte(u64 pte
)
248 return is_shadow_present_pte(pte
);
251 static int is_last_spte(u64 pte
, int level
)
253 if (level
== PT_PAGE_TABLE_LEVEL
)
255 if (is_large_pte(pte
))
260 static pfn_t
spte_to_pfn(u64 pte
)
262 return (pte
& PT64_BASE_ADDR_MASK
) >> PAGE_SHIFT
;
265 static gfn_t
pse36_gfn_delta(u32 gpte
)
267 int shift
= 32 - PT32_DIR_PSE36_SHIFT
- PAGE_SHIFT
;
269 return (gpte
& PT32_DIR_PSE36_MASK
) << shift
;
272 static void __set_spte(u64
*sptep
, u64 spte
)
274 set_64bit(sptep
, spte
);
277 static u64
__xchg_spte(u64
*sptep
, u64 new_spte
)
280 return xchg(sptep
, new_spte
);
286 } while (cmpxchg64(sptep
, old_spte
, new_spte
) != old_spte
);
292 static bool spte_has_volatile_bits(u64 spte
)
294 if (!shadow_accessed_mask
)
297 if (!is_shadow_present_pte(spte
))
300 if ((spte
& shadow_accessed_mask
) &&
301 (!is_writable_pte(spte
) || (spte
& shadow_dirty_mask
)))
307 static bool spte_is_bit_cleared(u64 old_spte
, u64 new_spte
, u64 bit_mask
)
309 return (old_spte
& bit_mask
) && !(new_spte
& bit_mask
);
312 static void update_spte(u64
*sptep
, u64 new_spte
)
314 u64 mask
, old_spte
= *sptep
;
316 WARN_ON(!is_rmap_spte(new_spte
));
318 new_spte
|= old_spte
& shadow_dirty_mask
;
320 mask
= shadow_accessed_mask
;
321 if (is_writable_pte(old_spte
))
322 mask
|= shadow_dirty_mask
;
324 if (!spte_has_volatile_bits(old_spte
) || (new_spte
& mask
) == mask
)
325 __set_spte(sptep
, new_spte
);
327 old_spte
= __xchg_spte(sptep
, new_spte
);
329 if (!shadow_accessed_mask
)
332 if (spte_is_bit_cleared(old_spte
, new_spte
, shadow_accessed_mask
))
333 kvm_set_pfn_accessed(spte_to_pfn(old_spte
));
334 if (spte_is_bit_cleared(old_spte
, new_spte
, shadow_dirty_mask
))
335 kvm_set_pfn_dirty(spte_to_pfn(old_spte
));
338 static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache
*cache
,
339 struct kmem_cache
*base_cache
, int min
)
343 if (cache
->nobjs
>= min
)
345 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
346 obj
= kmem_cache_zalloc(base_cache
, GFP_KERNEL
);
349 cache
->objects
[cache
->nobjs
++] = obj
;
354 static void mmu_free_memory_cache(struct kvm_mmu_memory_cache
*mc
,
355 struct kmem_cache
*cache
)
358 kmem_cache_free(cache
, mc
->objects
[--mc
->nobjs
]);
361 static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache
*cache
,
366 if (cache
->nobjs
>= min
)
368 while (cache
->nobjs
< ARRAY_SIZE(cache
->objects
)) {
369 page
= (void *)__get_free_page(GFP_KERNEL
);
372 cache
->objects
[cache
->nobjs
++] = page
;
377 static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache
*mc
)
380 free_page((unsigned long)mc
->objects
[--mc
->nobjs
]);
383 static int mmu_topup_memory_caches(struct kvm_vcpu
*vcpu
)
387 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_pte_list_desc_cache
,
388 pte_list_desc_cache
, 8 + PTE_PREFETCH_NUM
);
391 r
= mmu_topup_memory_cache_page(&vcpu
->arch
.mmu_page_cache
, 8);
394 r
= mmu_topup_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
395 mmu_page_header_cache
, 4);
400 static void mmu_free_memory_caches(struct kvm_vcpu
*vcpu
)
402 mmu_free_memory_cache(&vcpu
->arch
.mmu_pte_list_desc_cache
,
403 pte_list_desc_cache
);
404 mmu_free_memory_cache_page(&vcpu
->arch
.mmu_page_cache
);
405 mmu_free_memory_cache(&vcpu
->arch
.mmu_page_header_cache
,
406 mmu_page_header_cache
);
409 static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache
*mc
,
415 p
= mc
->objects
[--mc
->nobjs
];
419 static struct pte_list_desc
*mmu_alloc_pte_list_desc(struct kvm_vcpu
*vcpu
)
421 return mmu_memory_cache_alloc(&vcpu
->arch
.mmu_pte_list_desc_cache
,
422 sizeof(struct pte_list_desc
));
425 static void mmu_free_pte_list_desc(struct pte_list_desc
*pte_list_desc
)
427 kmem_cache_free(pte_list_desc_cache
, pte_list_desc
);
430 static gfn_t
kvm_mmu_page_get_gfn(struct kvm_mmu_page
*sp
, int index
)
432 if (!sp
->role
.direct
)
433 return sp
->gfns
[index
];
435 return sp
->gfn
+ (index
<< ((sp
->role
.level
- 1) * PT64_LEVEL_BITS
));
438 static void kvm_mmu_page_set_gfn(struct kvm_mmu_page
*sp
, int index
, gfn_t gfn
)
441 BUG_ON(gfn
!= kvm_mmu_page_get_gfn(sp
, index
));
443 sp
->gfns
[index
] = gfn
;
447 * Return the pointer to the large page information for a given gfn,
448 * handling slots that are not large page aligned.
450 static struct kvm_lpage_info
*lpage_info_slot(gfn_t gfn
,
451 struct kvm_memory_slot
*slot
,
456 idx
= (gfn
>> KVM_HPAGE_GFN_SHIFT(level
)) -
457 (slot
->base_gfn
>> KVM_HPAGE_GFN_SHIFT(level
));
458 return &slot
->lpage_info
[level
- 2][idx
];
461 static void account_shadowed(struct kvm
*kvm
, gfn_t gfn
)
463 struct kvm_memory_slot
*slot
;
464 struct kvm_lpage_info
*linfo
;
467 slot
= gfn_to_memslot(kvm
, gfn
);
468 for (i
= PT_DIRECTORY_LEVEL
;
469 i
< PT_PAGE_TABLE_LEVEL
+ KVM_NR_PAGE_SIZES
; ++i
) {
470 linfo
= lpage_info_slot(gfn
, slot
, i
);
471 linfo
->write_count
+= 1;
473 kvm
->arch
.indirect_shadow_pages
++;
476 static void unaccount_shadowed(struct kvm
*kvm
, gfn_t gfn
)
478 struct kvm_memory_slot
*slot
;
479 struct kvm_lpage_info
*linfo
;
482 slot
= gfn_to_memslot(kvm
, gfn
);
483 for (i
= PT_DIRECTORY_LEVEL
;
484 i
< PT_PAGE_TABLE_LEVEL
+ KVM_NR_PAGE_SIZES
; ++i
) {
485 linfo
= lpage_info_slot(gfn
, slot
, i
);
486 linfo
->write_count
-= 1;
487 WARN_ON(linfo
->write_count
< 0);
489 kvm
->arch
.indirect_shadow_pages
--;
492 static int has_wrprotected_page(struct kvm
*kvm
,
496 struct kvm_memory_slot
*slot
;
497 struct kvm_lpage_info
*linfo
;
499 slot
= gfn_to_memslot(kvm
, gfn
);
501 linfo
= lpage_info_slot(gfn
, slot
, level
);
502 return linfo
->write_count
;
508 static int host_mapping_level(struct kvm
*kvm
, gfn_t gfn
)
510 unsigned long page_size
;
513 page_size
= kvm_host_page_size(kvm
, gfn
);
515 for (i
= PT_PAGE_TABLE_LEVEL
;
516 i
< (PT_PAGE_TABLE_LEVEL
+ KVM_NR_PAGE_SIZES
); ++i
) {
517 if (page_size
>= KVM_HPAGE_SIZE(i
))
526 static struct kvm_memory_slot
*
527 gfn_to_memslot_dirty_bitmap(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
530 struct kvm_memory_slot
*slot
;
532 slot
= gfn_to_memslot(vcpu
->kvm
, gfn
);
533 if (!slot
|| slot
->flags
& KVM_MEMSLOT_INVALID
||
534 (no_dirty_log
&& slot
->dirty_bitmap
))
540 static bool mapping_level_dirty_bitmap(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
542 return !gfn_to_memslot_dirty_bitmap(vcpu
, large_gfn
, true);
545 static int mapping_level(struct kvm_vcpu
*vcpu
, gfn_t large_gfn
)
547 int host_level
, level
, max_level
;
549 host_level
= host_mapping_level(vcpu
->kvm
, large_gfn
);
551 if (host_level
== PT_PAGE_TABLE_LEVEL
)
554 max_level
= kvm_x86_ops
->get_lpage_level() < host_level
?
555 kvm_x86_ops
->get_lpage_level() : host_level
;
557 for (level
= PT_DIRECTORY_LEVEL
; level
<= max_level
; ++level
)
558 if (has_wrprotected_page(vcpu
->kvm
, large_gfn
, level
))
565 * Pte mapping structures:
567 * If pte_list bit zero is zero, then pte_list point to the spte.
569 * If pte_list bit zero is one, (then pte_list & ~1) points to a struct
570 * pte_list_desc containing more mappings.
572 * Returns the number of pte entries before the spte was added or zero if
573 * the spte was not added.
576 static int pte_list_add(struct kvm_vcpu
*vcpu
, u64
*spte
,
577 unsigned long *pte_list
)
579 struct pte_list_desc
*desc
;
583 rmap_printk("pte_list_add: %p %llx 0->1\n", spte
, *spte
);
584 *pte_list
= (unsigned long)spte
;
585 } else if (!(*pte_list
& 1)) {
586 rmap_printk("pte_list_add: %p %llx 1->many\n", spte
, *spte
);
587 desc
= mmu_alloc_pte_list_desc(vcpu
);
588 desc
->sptes
[0] = (u64
*)*pte_list
;
589 desc
->sptes
[1] = spte
;
590 *pte_list
= (unsigned long)desc
| 1;
593 rmap_printk("pte_list_add: %p %llx many->many\n", spte
, *spte
);
594 desc
= (struct pte_list_desc
*)(*pte_list
& ~1ul);
595 while (desc
->sptes
[PTE_LIST_EXT
-1] && desc
->more
) {
597 count
+= PTE_LIST_EXT
;
599 if (desc
->sptes
[PTE_LIST_EXT
-1]) {
600 desc
->more
= mmu_alloc_pte_list_desc(vcpu
);
603 for (i
= 0; desc
->sptes
[i
]; ++i
)
605 desc
->sptes
[i
] = spte
;
610 static u64
*pte_list_next(unsigned long *pte_list
, u64
*spte
)
612 struct pte_list_desc
*desc
;
618 else if (!(*pte_list
& 1)) {
620 return (u64
*)*pte_list
;
623 desc
= (struct pte_list_desc
*)(*pte_list
& ~1ul);
626 for (i
= 0; i
< PTE_LIST_EXT
&& desc
->sptes
[i
]; ++i
) {
627 if (prev_spte
== spte
)
628 return desc
->sptes
[i
];
629 prev_spte
= desc
->sptes
[i
];
637 pte_list_desc_remove_entry(unsigned long *pte_list
, struct pte_list_desc
*desc
,
638 int i
, struct pte_list_desc
*prev_desc
)
642 for (j
= PTE_LIST_EXT
- 1; !desc
->sptes
[j
] && j
> i
; --j
)
644 desc
->sptes
[i
] = desc
->sptes
[j
];
645 desc
->sptes
[j
] = NULL
;
648 if (!prev_desc
&& !desc
->more
)
649 *pte_list
= (unsigned long)desc
->sptes
[0];
652 prev_desc
->more
= desc
->more
;
654 *pte_list
= (unsigned long)desc
->more
| 1;
655 mmu_free_pte_list_desc(desc
);
658 static void pte_list_remove(u64
*spte
, unsigned long *pte_list
)
660 struct pte_list_desc
*desc
;
661 struct pte_list_desc
*prev_desc
;
665 printk(KERN_ERR
"pte_list_remove: %p 0->BUG\n", spte
);
667 } else if (!(*pte_list
& 1)) {
668 rmap_printk("pte_list_remove: %p 1->0\n", spte
);
669 if ((u64
*)*pte_list
!= spte
) {
670 printk(KERN_ERR
"pte_list_remove: %p 1->BUG\n", spte
);
675 rmap_printk("pte_list_remove: %p many->many\n", spte
);
676 desc
= (struct pte_list_desc
*)(*pte_list
& ~1ul);
679 for (i
= 0; i
< PTE_LIST_EXT
&& desc
->sptes
[i
]; ++i
)
680 if (desc
->sptes
[i
] == spte
) {
681 pte_list_desc_remove_entry(pte_list
,
689 pr_err("pte_list_remove: %p many->many\n", spte
);
694 typedef void (*pte_list_walk_fn
) (u64
*spte
);
695 static void pte_list_walk(unsigned long *pte_list
, pte_list_walk_fn fn
)
697 struct pte_list_desc
*desc
;
703 if (!(*pte_list
& 1))
704 return fn((u64
*)*pte_list
);
706 desc
= (struct pte_list_desc
*)(*pte_list
& ~1ul);
708 for (i
= 0; i
< PTE_LIST_EXT
&& desc
->sptes
[i
]; ++i
)
715 * Take gfn and return the reverse mapping to it.
717 static unsigned long *gfn_to_rmap(struct kvm
*kvm
, gfn_t gfn
, int level
)
719 struct kvm_memory_slot
*slot
;
720 struct kvm_lpage_info
*linfo
;
722 slot
= gfn_to_memslot(kvm
, gfn
);
723 if (likely(level
== PT_PAGE_TABLE_LEVEL
))
724 return &slot
->rmap
[gfn
- slot
->base_gfn
];
726 linfo
= lpage_info_slot(gfn
, slot
, level
);
728 return &linfo
->rmap_pde
;
731 static int rmap_add(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
)
733 struct kvm_mmu_page
*sp
;
734 unsigned long *rmapp
;
736 sp
= page_header(__pa(spte
));
737 kvm_mmu_page_set_gfn(sp
, spte
- sp
->spt
, gfn
);
738 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, sp
->role
.level
);
739 return pte_list_add(vcpu
, spte
, rmapp
);
742 static u64
*rmap_next(struct kvm
*kvm
, unsigned long *rmapp
, u64
*spte
)
744 return pte_list_next(rmapp
, spte
);
747 static void rmap_remove(struct kvm
*kvm
, u64
*spte
)
749 struct kvm_mmu_page
*sp
;
751 unsigned long *rmapp
;
753 sp
= page_header(__pa(spte
));
754 gfn
= kvm_mmu_page_get_gfn(sp
, spte
- sp
->spt
);
755 rmapp
= gfn_to_rmap(kvm
, gfn
, sp
->role
.level
);
756 pte_list_remove(spte
, rmapp
);
759 static int set_spte_track_bits(u64
*sptep
, u64 new_spte
)
762 u64 old_spte
= *sptep
;
764 if (!spte_has_volatile_bits(old_spte
))
765 __set_spte(sptep
, new_spte
);
767 old_spte
= __xchg_spte(sptep
, new_spte
);
769 if (!is_rmap_spte(old_spte
))
772 pfn
= spte_to_pfn(old_spte
);
773 if (!shadow_accessed_mask
|| old_spte
& shadow_accessed_mask
)
774 kvm_set_pfn_accessed(pfn
);
775 if (!shadow_dirty_mask
|| (old_spte
& shadow_dirty_mask
))
776 kvm_set_pfn_dirty(pfn
);
780 static void drop_spte(struct kvm
*kvm
, u64
*sptep
, u64 new_spte
)
782 if (set_spte_track_bits(sptep
, new_spte
))
783 rmap_remove(kvm
, sptep
);
786 static int rmap_write_protect(struct kvm
*kvm
, u64 gfn
)
788 unsigned long *rmapp
;
790 int i
, write_protected
= 0;
792 rmapp
= gfn_to_rmap(kvm
, gfn
, PT_PAGE_TABLE_LEVEL
);
794 spte
= rmap_next(kvm
, rmapp
, NULL
);
797 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
798 rmap_printk("rmap_write_protect: spte %p %llx\n", spte
, *spte
);
799 if (is_writable_pte(*spte
)) {
800 update_spte(spte
, *spte
& ~PT_WRITABLE_MASK
);
803 spte
= rmap_next(kvm
, rmapp
, spte
);
806 /* check for huge page mappings */
807 for (i
= PT_DIRECTORY_LEVEL
;
808 i
< PT_PAGE_TABLE_LEVEL
+ KVM_NR_PAGE_SIZES
; ++i
) {
809 rmapp
= gfn_to_rmap(kvm
, gfn
, i
);
810 spte
= rmap_next(kvm
, rmapp
, NULL
);
813 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
814 BUG_ON((*spte
& (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
)) != (PT_PAGE_SIZE_MASK
|PT_PRESENT_MASK
));
815 pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte
, *spte
, gfn
);
816 if (is_writable_pte(*spte
)) {
818 shadow_trap_nonpresent_pte
);
823 spte
= rmap_next(kvm
, rmapp
, spte
);
827 return write_protected
;
830 static int kvm_unmap_rmapp(struct kvm
*kvm
, unsigned long *rmapp
,
834 int need_tlb_flush
= 0;
836 while ((spte
= rmap_next(kvm
, rmapp
, NULL
))) {
837 BUG_ON(!(*spte
& PT_PRESENT_MASK
));
838 rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", spte
, *spte
);
839 drop_spte(kvm
, spte
, shadow_trap_nonpresent_pte
);
842 return need_tlb_flush
;
845 static int kvm_set_pte_rmapp(struct kvm
*kvm
, unsigned long *rmapp
,
850 pte_t
*ptep
= (pte_t
*)data
;
853 WARN_ON(pte_huge(*ptep
));
854 new_pfn
= pte_pfn(*ptep
);
855 spte
= rmap_next(kvm
, rmapp
, NULL
);
857 BUG_ON(!is_shadow_present_pte(*spte
));
858 rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", spte
, *spte
);
860 if (pte_write(*ptep
)) {
861 drop_spte(kvm
, spte
, shadow_trap_nonpresent_pte
);
862 spte
= rmap_next(kvm
, rmapp
, NULL
);
864 new_spte
= *spte
&~ (PT64_BASE_ADDR_MASK
);
865 new_spte
|= (u64
)new_pfn
<< PAGE_SHIFT
;
867 new_spte
&= ~PT_WRITABLE_MASK
;
868 new_spte
&= ~SPTE_HOST_WRITEABLE
;
869 new_spte
&= ~shadow_accessed_mask
;
870 set_spte_track_bits(spte
, new_spte
);
871 spte
= rmap_next(kvm
, rmapp
, spte
);
875 kvm_flush_remote_tlbs(kvm
);
880 static int kvm_handle_hva(struct kvm
*kvm
, unsigned long hva
,
882 int (*handler
)(struct kvm
*kvm
, unsigned long *rmapp
,
888 struct kvm_memslots
*slots
;
890 slots
= kvm_memslots(kvm
);
892 for (i
= 0; i
< slots
->nmemslots
; i
++) {
893 struct kvm_memory_slot
*memslot
= &slots
->memslots
[i
];
894 unsigned long start
= memslot
->userspace_addr
;
897 end
= start
+ (memslot
->npages
<< PAGE_SHIFT
);
898 if (hva
>= start
&& hva
< end
) {
899 gfn_t gfn_offset
= (hva
- start
) >> PAGE_SHIFT
;
900 gfn_t gfn
= memslot
->base_gfn
+ gfn_offset
;
902 ret
= handler(kvm
, &memslot
->rmap
[gfn_offset
], data
);
904 for (j
= 0; j
< KVM_NR_PAGE_SIZES
- 1; ++j
) {
905 struct kvm_lpage_info
*linfo
;
907 linfo
= lpage_info_slot(gfn
, memslot
,
908 PT_DIRECTORY_LEVEL
+ j
);
909 ret
|= handler(kvm
, &linfo
->rmap_pde
, data
);
911 trace_kvm_age_page(hva
, memslot
, ret
);
919 int kvm_unmap_hva(struct kvm
*kvm
, unsigned long hva
)
921 return kvm_handle_hva(kvm
, hva
, 0, kvm_unmap_rmapp
);
924 void kvm_set_spte_hva(struct kvm
*kvm
, unsigned long hva
, pte_t pte
)
926 kvm_handle_hva(kvm
, hva
, (unsigned long)&pte
, kvm_set_pte_rmapp
);
929 static int kvm_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
,
936 * Emulate the accessed bit for EPT, by checking if this page has
937 * an EPT mapping, and clearing it if it does. On the next access,
938 * a new EPT mapping will be established.
939 * This has some overhead, but not as much as the cost of swapping
940 * out actively used pages or breaking up actively used hugepages.
942 if (!shadow_accessed_mask
)
943 return kvm_unmap_rmapp(kvm
, rmapp
, data
);
945 spte
= rmap_next(kvm
, rmapp
, NULL
);
949 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
950 _young
= _spte
& PT_ACCESSED_MASK
;
953 clear_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
955 spte
= rmap_next(kvm
, rmapp
, spte
);
960 static int kvm_test_age_rmapp(struct kvm
*kvm
, unsigned long *rmapp
,
967 * If there's no access bit in the secondary pte set by the
968 * hardware it's up to gup-fast/gup to set the access bit in
969 * the primary pte or in the page structure.
971 if (!shadow_accessed_mask
)
974 spte
= rmap_next(kvm
, rmapp
, NULL
);
977 BUG_ON(!(_spte
& PT_PRESENT_MASK
));
978 young
= _spte
& PT_ACCESSED_MASK
;
983 spte
= rmap_next(kvm
, rmapp
, spte
);
989 #define RMAP_RECYCLE_THRESHOLD 1000
991 static void rmap_recycle(struct kvm_vcpu
*vcpu
, u64
*spte
, gfn_t gfn
)
993 unsigned long *rmapp
;
994 struct kvm_mmu_page
*sp
;
996 sp
= page_header(__pa(spte
));
998 rmapp
= gfn_to_rmap(vcpu
->kvm
, gfn
, sp
->role
.level
);
1000 kvm_unmap_rmapp(vcpu
->kvm
, rmapp
, 0);
1001 kvm_flush_remote_tlbs(vcpu
->kvm
);
1004 int kvm_age_hva(struct kvm
*kvm
, unsigned long hva
)
1006 return kvm_handle_hva(kvm
, hva
, 0, kvm_age_rmapp
);
1009 int kvm_test_age_hva(struct kvm
*kvm
, unsigned long hva
)
1011 return kvm_handle_hva(kvm
, hva
, 0, kvm_test_age_rmapp
);
1015 static int is_empty_shadow_page(u64
*spt
)
1020 for (pos
= spt
, end
= pos
+ PAGE_SIZE
/ sizeof(u64
); pos
!= end
; pos
++)
1021 if (is_shadow_present_pte(*pos
)) {
1022 printk(KERN_ERR
"%s: %p %llx\n", __func__
,
1031 * This value is the sum of all of the kvm instances's
1032 * kvm->arch.n_used_mmu_pages values. We need a global,
1033 * aggregate version in order to make the slab shrinker
1036 static inline void kvm_mod_used_mmu_pages(struct kvm
*kvm
, int nr
)
1038 kvm
->arch
.n_used_mmu_pages
+= nr
;
1039 percpu_counter_add(&kvm_total_used_mmu_pages
, nr
);
1042 static void kvm_mmu_free_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1044 ASSERT(is_empty_shadow_page(sp
->spt
));
1045 hlist_del(&sp
->hash_link
);
1046 list_del(&sp
->link
);
1047 free_page((unsigned long)sp
->spt
);
1048 if (!sp
->role
.direct
)
1049 free_page((unsigned long)sp
->gfns
);
1050 kmem_cache_free(mmu_page_header_cache
, sp
);
1051 kvm_mod_used_mmu_pages(kvm
, -1);
1054 static unsigned kvm_page_table_hashfn(gfn_t gfn
)
1056 return gfn
& ((1 << KVM_MMU_HASH_SHIFT
) - 1);
1059 static void mmu_page_add_parent_pte(struct kvm_vcpu
*vcpu
,
1060 struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1065 pte_list_add(vcpu
, parent_pte
, &sp
->parent_ptes
);
1068 static void mmu_page_remove_parent_pte(struct kvm_mmu_page
*sp
,
1071 pte_list_remove(parent_pte
, &sp
->parent_ptes
);
1074 static void drop_parent_pte(struct kvm_mmu_page
*sp
,
1077 mmu_page_remove_parent_pte(sp
, parent_pte
);
1078 __set_spte(parent_pte
, shadow_trap_nonpresent_pte
);
1081 static struct kvm_mmu_page
*kvm_mmu_alloc_page(struct kvm_vcpu
*vcpu
,
1082 u64
*parent_pte
, int direct
)
1084 struct kvm_mmu_page
*sp
;
1085 sp
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_header_cache
,
1087 sp
->spt
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
, PAGE_SIZE
);
1089 sp
->gfns
= mmu_memory_cache_alloc(&vcpu
->arch
.mmu_page_cache
,
1091 set_page_private(virt_to_page(sp
->spt
), (unsigned long)sp
);
1092 list_add(&sp
->link
, &vcpu
->kvm
->arch
.active_mmu_pages
);
1093 bitmap_zero(sp
->slot_bitmap
, KVM_MEMORY_SLOTS
+ KVM_PRIVATE_MEM_SLOTS
);
1094 sp
->parent_ptes
= 0;
1095 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1096 kvm_mod_used_mmu_pages(vcpu
->kvm
, +1);
1100 static void mark_unsync(u64
*spte
);
1101 static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page
*sp
)
1103 pte_list_walk(&sp
->parent_ptes
, mark_unsync
);
1106 static void mark_unsync(u64
*spte
)
1108 struct kvm_mmu_page
*sp
;
1111 sp
= page_header(__pa(spte
));
1112 index
= spte
- sp
->spt
;
1113 if (__test_and_set_bit(index
, sp
->unsync_child_bitmap
))
1115 if (sp
->unsync_children
++)
1117 kvm_mmu_mark_parents_unsync(sp
);
1120 static void nonpaging_prefetch_page(struct kvm_vcpu
*vcpu
,
1121 struct kvm_mmu_page
*sp
)
1125 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1126 sp
->spt
[i
] = shadow_trap_nonpresent_pte
;
1129 static int nonpaging_sync_page(struct kvm_vcpu
*vcpu
,
1130 struct kvm_mmu_page
*sp
)
1135 static void nonpaging_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
1139 static void nonpaging_update_pte(struct kvm_vcpu
*vcpu
,
1140 struct kvm_mmu_page
*sp
, u64
*spte
,
1146 #define KVM_PAGE_ARRAY_NR 16
1148 struct kvm_mmu_pages
{
1149 struct mmu_page_and_offset
{
1150 struct kvm_mmu_page
*sp
;
1152 } page
[KVM_PAGE_ARRAY_NR
];
1156 #define for_each_unsync_children(bitmap, idx) \
1157 for (idx = find_first_bit(bitmap, 512); \
1159 idx = find_next_bit(bitmap, 512, idx+1))
1161 static int mmu_pages_add(struct kvm_mmu_pages
*pvec
, struct kvm_mmu_page
*sp
,
1167 for (i
=0; i
< pvec
->nr
; i
++)
1168 if (pvec
->page
[i
].sp
== sp
)
1171 pvec
->page
[pvec
->nr
].sp
= sp
;
1172 pvec
->page
[pvec
->nr
].idx
= idx
;
1174 return (pvec
->nr
== KVM_PAGE_ARRAY_NR
);
1177 static int __mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1178 struct kvm_mmu_pages
*pvec
)
1180 int i
, ret
, nr_unsync_leaf
= 0;
1182 for_each_unsync_children(sp
->unsync_child_bitmap
, i
) {
1183 struct kvm_mmu_page
*child
;
1184 u64 ent
= sp
->spt
[i
];
1186 if (!is_shadow_present_pte(ent
) || is_large_pte(ent
))
1187 goto clear_child_bitmap
;
1189 child
= page_header(ent
& PT64_BASE_ADDR_MASK
);
1191 if (child
->unsync_children
) {
1192 if (mmu_pages_add(pvec
, child
, i
))
1195 ret
= __mmu_unsync_walk(child
, pvec
);
1197 goto clear_child_bitmap
;
1199 nr_unsync_leaf
+= ret
;
1202 } else if (child
->unsync
) {
1204 if (mmu_pages_add(pvec
, child
, i
))
1207 goto clear_child_bitmap
;
1212 __clear_bit(i
, sp
->unsync_child_bitmap
);
1213 sp
->unsync_children
--;
1214 WARN_ON((int)sp
->unsync_children
< 0);
1218 return nr_unsync_leaf
;
1221 static int mmu_unsync_walk(struct kvm_mmu_page
*sp
,
1222 struct kvm_mmu_pages
*pvec
)
1224 if (!sp
->unsync_children
)
1227 mmu_pages_add(pvec
, sp
, 0);
1228 return __mmu_unsync_walk(sp
, pvec
);
1231 static void kvm_unlink_unsync_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1233 WARN_ON(!sp
->unsync
);
1234 trace_kvm_mmu_sync_page(sp
);
1236 --kvm
->stat
.mmu_unsync
;
1239 static int kvm_mmu_prepare_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
,
1240 struct list_head
*invalid_list
);
1241 static void kvm_mmu_commit_zap_page(struct kvm
*kvm
,
1242 struct list_head
*invalid_list
);
1244 #define for_each_gfn_sp(kvm, sp, gfn, pos) \
1245 hlist_for_each_entry(sp, pos, \
1246 &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \
1247 if ((sp)->gfn != (gfn)) {} else
1249 #define for_each_gfn_indirect_valid_sp(kvm, sp, gfn, pos) \
1250 hlist_for_each_entry(sp, pos, \
1251 &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \
1252 if ((sp)->gfn != (gfn) || (sp)->role.direct || \
1253 (sp)->role.invalid) {} else
1255 /* @sp->gfn should be write-protected at the call site */
1256 static int __kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
1257 struct list_head
*invalid_list
, bool clear_unsync
)
1259 if (sp
->role
.cr4_pae
!= !!is_pae(vcpu
)) {
1260 kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
, invalid_list
);
1265 kvm_unlink_unsync_page(vcpu
->kvm
, sp
);
1267 if (vcpu
->arch
.mmu
.sync_page(vcpu
, sp
)) {
1268 kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
, invalid_list
);
1272 kvm_mmu_flush_tlb(vcpu
);
1276 static int kvm_sync_page_transient(struct kvm_vcpu
*vcpu
,
1277 struct kvm_mmu_page
*sp
)
1279 LIST_HEAD(invalid_list
);
1282 ret
= __kvm_sync_page(vcpu
, sp
, &invalid_list
, false);
1284 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
1289 static int kvm_sync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
,
1290 struct list_head
*invalid_list
)
1292 return __kvm_sync_page(vcpu
, sp
, invalid_list
, true);
1295 /* @gfn should be write-protected at the call site */
1296 static void kvm_sync_pages(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1298 struct kvm_mmu_page
*s
;
1299 struct hlist_node
*node
;
1300 LIST_HEAD(invalid_list
);
1303 for_each_gfn_indirect_valid_sp(vcpu
->kvm
, s
, gfn
, node
) {
1307 WARN_ON(s
->role
.level
!= PT_PAGE_TABLE_LEVEL
);
1308 kvm_unlink_unsync_page(vcpu
->kvm
, s
);
1309 if ((s
->role
.cr4_pae
!= !!is_pae(vcpu
)) ||
1310 (vcpu
->arch
.mmu
.sync_page(vcpu
, s
))) {
1311 kvm_mmu_prepare_zap_page(vcpu
->kvm
, s
, &invalid_list
);
1317 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
1319 kvm_mmu_flush_tlb(vcpu
);
1322 struct mmu_page_path
{
1323 struct kvm_mmu_page
*parent
[PT64_ROOT_LEVEL
-1];
1324 unsigned int idx
[PT64_ROOT_LEVEL
-1];
1327 #define for_each_sp(pvec, sp, parents, i) \
1328 for (i = mmu_pages_next(&pvec, &parents, -1), \
1329 sp = pvec.page[i].sp; \
1330 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \
1331 i = mmu_pages_next(&pvec, &parents, i))
1333 static int mmu_pages_next(struct kvm_mmu_pages
*pvec
,
1334 struct mmu_page_path
*parents
,
1339 for (n
= i
+1; n
< pvec
->nr
; n
++) {
1340 struct kvm_mmu_page
*sp
= pvec
->page
[n
].sp
;
1342 if (sp
->role
.level
== PT_PAGE_TABLE_LEVEL
) {
1343 parents
->idx
[0] = pvec
->page
[n
].idx
;
1347 parents
->parent
[sp
->role
.level
-2] = sp
;
1348 parents
->idx
[sp
->role
.level
-1] = pvec
->page
[n
].idx
;
1354 static void mmu_pages_clear_parents(struct mmu_page_path
*parents
)
1356 struct kvm_mmu_page
*sp
;
1357 unsigned int level
= 0;
1360 unsigned int idx
= parents
->idx
[level
];
1362 sp
= parents
->parent
[level
];
1366 --sp
->unsync_children
;
1367 WARN_ON((int)sp
->unsync_children
< 0);
1368 __clear_bit(idx
, sp
->unsync_child_bitmap
);
1370 } while (level
< PT64_ROOT_LEVEL
-1 && !sp
->unsync_children
);
1373 static void kvm_mmu_pages_init(struct kvm_mmu_page
*parent
,
1374 struct mmu_page_path
*parents
,
1375 struct kvm_mmu_pages
*pvec
)
1377 parents
->parent
[parent
->role
.level
-1] = NULL
;
1381 static void mmu_sync_children(struct kvm_vcpu
*vcpu
,
1382 struct kvm_mmu_page
*parent
)
1385 struct kvm_mmu_page
*sp
;
1386 struct mmu_page_path parents
;
1387 struct kvm_mmu_pages pages
;
1388 LIST_HEAD(invalid_list
);
1390 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1391 while (mmu_unsync_walk(parent
, &pages
)) {
1394 for_each_sp(pages
, sp
, parents
, i
)
1395 protected |= rmap_write_protect(vcpu
->kvm
, sp
->gfn
);
1398 kvm_flush_remote_tlbs(vcpu
->kvm
);
1400 for_each_sp(pages
, sp
, parents
, i
) {
1401 kvm_sync_page(vcpu
, sp
, &invalid_list
);
1402 mmu_pages_clear_parents(&parents
);
1404 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
1405 cond_resched_lock(&vcpu
->kvm
->mmu_lock
);
1406 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1410 static struct kvm_mmu_page
*kvm_mmu_get_page(struct kvm_vcpu
*vcpu
,
1418 union kvm_mmu_page_role role
;
1420 struct kvm_mmu_page
*sp
;
1421 struct hlist_node
*node
;
1422 bool need_sync
= false;
1424 role
= vcpu
->arch
.mmu
.base_role
;
1426 role
.direct
= direct
;
1429 role
.access
= access
;
1430 if (!vcpu
->arch
.mmu
.direct_map
1431 && vcpu
->arch
.mmu
.root_level
<= PT32_ROOT_LEVEL
) {
1432 quadrant
= gaddr
>> (PAGE_SHIFT
+ (PT64_PT_BITS
* level
));
1433 quadrant
&= (1 << ((PT32_PT_BITS
- PT64_PT_BITS
) * level
)) - 1;
1434 role
.quadrant
= quadrant
;
1436 for_each_gfn_sp(vcpu
->kvm
, sp
, gfn
, node
) {
1437 if (!need_sync
&& sp
->unsync
)
1440 if (sp
->role
.word
!= role
.word
)
1443 if (sp
->unsync
&& kvm_sync_page_transient(vcpu
, sp
))
1446 mmu_page_add_parent_pte(vcpu
, sp
, parent_pte
);
1447 if (sp
->unsync_children
) {
1448 kvm_make_request(KVM_REQ_MMU_SYNC
, vcpu
);
1449 kvm_mmu_mark_parents_unsync(sp
);
1450 } else if (sp
->unsync
)
1451 kvm_mmu_mark_parents_unsync(sp
);
1453 trace_kvm_mmu_get_page(sp
, false);
1456 ++vcpu
->kvm
->stat
.mmu_cache_miss
;
1457 sp
= kvm_mmu_alloc_page(vcpu
, parent_pte
, direct
);
1462 hlist_add_head(&sp
->hash_link
,
1463 &vcpu
->kvm
->arch
.mmu_page_hash
[kvm_page_table_hashfn(gfn
)]);
1465 if (rmap_write_protect(vcpu
->kvm
, gfn
))
1466 kvm_flush_remote_tlbs(vcpu
->kvm
);
1467 if (level
> PT_PAGE_TABLE_LEVEL
&& need_sync
)
1468 kvm_sync_pages(vcpu
, gfn
);
1470 account_shadowed(vcpu
->kvm
, gfn
);
1472 if (shadow_trap_nonpresent_pte
!= shadow_notrap_nonpresent_pte
)
1473 vcpu
->arch
.mmu
.prefetch_page(vcpu
, sp
);
1475 nonpaging_prefetch_page(vcpu
, sp
);
1476 trace_kvm_mmu_get_page(sp
, true);
1480 static void shadow_walk_init(struct kvm_shadow_walk_iterator
*iterator
,
1481 struct kvm_vcpu
*vcpu
, u64 addr
)
1483 iterator
->addr
= addr
;
1484 iterator
->shadow_addr
= vcpu
->arch
.mmu
.root_hpa
;
1485 iterator
->level
= vcpu
->arch
.mmu
.shadow_root_level
;
1487 if (iterator
->level
== PT64_ROOT_LEVEL
&&
1488 vcpu
->arch
.mmu
.root_level
< PT64_ROOT_LEVEL
&&
1489 !vcpu
->arch
.mmu
.direct_map
)
1492 if (iterator
->level
== PT32E_ROOT_LEVEL
) {
1493 iterator
->shadow_addr
1494 = vcpu
->arch
.mmu
.pae_root
[(addr
>> 30) & 3];
1495 iterator
->shadow_addr
&= PT64_BASE_ADDR_MASK
;
1497 if (!iterator
->shadow_addr
)
1498 iterator
->level
= 0;
1502 static bool shadow_walk_okay(struct kvm_shadow_walk_iterator
*iterator
)
1504 if (iterator
->level
< PT_PAGE_TABLE_LEVEL
)
1507 iterator
->index
= SHADOW_PT_INDEX(iterator
->addr
, iterator
->level
);
1508 iterator
->sptep
= ((u64
*)__va(iterator
->shadow_addr
)) + iterator
->index
;
1512 static void shadow_walk_next(struct kvm_shadow_walk_iterator
*iterator
)
1514 if (is_last_spte(*iterator
->sptep
, iterator
->level
)) {
1515 iterator
->level
= 0;
1519 iterator
->shadow_addr
= *iterator
->sptep
& PT64_BASE_ADDR_MASK
;
1523 static void link_shadow_page(u64
*sptep
, struct kvm_mmu_page
*sp
)
1527 spte
= __pa(sp
->spt
)
1528 | PT_PRESENT_MASK
| PT_ACCESSED_MASK
1529 | PT_WRITABLE_MASK
| PT_USER_MASK
;
1530 __set_spte(sptep
, spte
);
1533 static void drop_large_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
)
1535 if (is_large_pte(*sptep
)) {
1536 drop_spte(vcpu
->kvm
, sptep
, shadow_trap_nonpresent_pte
);
1537 kvm_flush_remote_tlbs(vcpu
->kvm
);
1541 static void validate_direct_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
,
1542 unsigned direct_access
)
1544 if (is_shadow_present_pte(*sptep
) && !is_large_pte(*sptep
)) {
1545 struct kvm_mmu_page
*child
;
1548 * For the direct sp, if the guest pte's dirty bit
1549 * changed form clean to dirty, it will corrupt the
1550 * sp's access: allow writable in the read-only sp,
1551 * so we should update the spte at this point to get
1552 * a new sp with the correct access.
1554 child
= page_header(*sptep
& PT64_BASE_ADDR_MASK
);
1555 if (child
->role
.access
== direct_access
)
1558 drop_parent_pte(child
, sptep
);
1559 kvm_flush_remote_tlbs(vcpu
->kvm
);
1563 static void mmu_page_zap_pte(struct kvm
*kvm
, struct kvm_mmu_page
*sp
,
1567 struct kvm_mmu_page
*child
;
1570 if (is_shadow_present_pte(pte
)) {
1571 if (is_last_spte(pte
, sp
->role
.level
))
1572 drop_spte(kvm
, spte
, shadow_trap_nonpresent_pte
);
1574 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
1575 drop_parent_pte(child
, spte
);
1578 __set_spte(spte
, shadow_trap_nonpresent_pte
);
1579 if (is_large_pte(pte
))
1583 static void kvm_mmu_page_unlink_children(struct kvm
*kvm
,
1584 struct kvm_mmu_page
*sp
)
1588 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
)
1589 mmu_page_zap_pte(kvm
, sp
, sp
->spt
+ i
);
1592 static void kvm_mmu_put_page(struct kvm_mmu_page
*sp
, u64
*parent_pte
)
1594 mmu_page_remove_parent_pte(sp
, parent_pte
);
1597 static void kvm_mmu_reset_last_pte_updated(struct kvm
*kvm
)
1600 struct kvm_vcpu
*vcpu
;
1602 kvm_for_each_vcpu(i
, vcpu
, kvm
)
1603 vcpu
->arch
.last_pte_updated
= NULL
;
1606 static void kvm_mmu_unlink_parents(struct kvm
*kvm
, struct kvm_mmu_page
*sp
)
1610 while ((parent_pte
= pte_list_next(&sp
->parent_ptes
, NULL
)))
1611 drop_parent_pte(sp
, parent_pte
);
1614 static int mmu_zap_unsync_children(struct kvm
*kvm
,
1615 struct kvm_mmu_page
*parent
,
1616 struct list_head
*invalid_list
)
1619 struct mmu_page_path parents
;
1620 struct kvm_mmu_pages pages
;
1622 if (parent
->role
.level
== PT_PAGE_TABLE_LEVEL
)
1625 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1626 while (mmu_unsync_walk(parent
, &pages
)) {
1627 struct kvm_mmu_page
*sp
;
1629 for_each_sp(pages
, sp
, parents
, i
) {
1630 kvm_mmu_prepare_zap_page(kvm
, sp
, invalid_list
);
1631 mmu_pages_clear_parents(&parents
);
1634 kvm_mmu_pages_init(parent
, &parents
, &pages
);
1640 static int kvm_mmu_prepare_zap_page(struct kvm
*kvm
, struct kvm_mmu_page
*sp
,
1641 struct list_head
*invalid_list
)
1645 trace_kvm_mmu_prepare_zap_page(sp
);
1646 ++kvm
->stat
.mmu_shadow_zapped
;
1647 ret
= mmu_zap_unsync_children(kvm
, sp
, invalid_list
);
1648 kvm_mmu_page_unlink_children(kvm
, sp
);
1649 kvm_mmu_unlink_parents(kvm
, sp
);
1650 if (!sp
->role
.invalid
&& !sp
->role
.direct
)
1651 unaccount_shadowed(kvm
, sp
->gfn
);
1653 kvm_unlink_unsync_page(kvm
, sp
);
1654 if (!sp
->root_count
) {
1657 list_move(&sp
->link
, invalid_list
);
1659 list_move(&sp
->link
, &kvm
->arch
.active_mmu_pages
);
1660 kvm_reload_remote_mmus(kvm
);
1663 sp
->role
.invalid
= 1;
1664 kvm_mmu_reset_last_pte_updated(kvm
);
1668 static void kvm_mmu_commit_zap_page(struct kvm
*kvm
,
1669 struct list_head
*invalid_list
)
1671 struct kvm_mmu_page
*sp
;
1673 if (list_empty(invalid_list
))
1676 kvm_flush_remote_tlbs(kvm
);
1679 sp
= list_first_entry(invalid_list
, struct kvm_mmu_page
, link
);
1680 WARN_ON(!sp
->role
.invalid
|| sp
->root_count
);
1681 kvm_mmu_free_page(kvm
, sp
);
1682 } while (!list_empty(invalid_list
));
1687 * Changing the number of mmu pages allocated to the vm
1688 * Note: if goal_nr_mmu_pages is too small, you will get dead lock
1690 void kvm_mmu_change_mmu_pages(struct kvm
*kvm
, unsigned int goal_nr_mmu_pages
)
1692 LIST_HEAD(invalid_list
);
1694 * If we set the number of mmu pages to be smaller be than the
1695 * number of actived pages , we must to free some mmu pages before we
1699 if (kvm
->arch
.n_used_mmu_pages
> goal_nr_mmu_pages
) {
1700 while (kvm
->arch
.n_used_mmu_pages
> goal_nr_mmu_pages
&&
1701 !list_empty(&kvm
->arch
.active_mmu_pages
)) {
1702 struct kvm_mmu_page
*page
;
1704 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
1705 struct kvm_mmu_page
, link
);
1706 kvm_mmu_prepare_zap_page(kvm
, page
, &invalid_list
);
1707 kvm_mmu_commit_zap_page(kvm
, &invalid_list
);
1709 goal_nr_mmu_pages
= kvm
->arch
.n_used_mmu_pages
;
1712 kvm
->arch
.n_max_mmu_pages
= goal_nr_mmu_pages
;
1715 static int kvm_mmu_unprotect_page(struct kvm
*kvm
, gfn_t gfn
)
1717 struct kvm_mmu_page
*sp
;
1718 struct hlist_node
*node
;
1719 LIST_HEAD(invalid_list
);
1722 pgprintk("%s: looking for gfn %llx\n", __func__
, gfn
);
1725 for_each_gfn_indirect_valid_sp(kvm
, sp
, gfn
, node
) {
1726 pgprintk("%s: gfn %llx role %x\n", __func__
, gfn
,
1729 kvm_mmu_prepare_zap_page(kvm
, sp
, &invalid_list
);
1731 kvm_mmu_commit_zap_page(kvm
, &invalid_list
);
1735 static void mmu_unshadow(struct kvm
*kvm
, gfn_t gfn
)
1737 struct kvm_mmu_page
*sp
;
1738 struct hlist_node
*node
;
1739 LIST_HEAD(invalid_list
);
1741 for_each_gfn_indirect_valid_sp(kvm
, sp
, gfn
, node
) {
1742 pgprintk("%s: zap %llx %x\n",
1743 __func__
, gfn
, sp
->role
.word
);
1744 kvm_mmu_prepare_zap_page(kvm
, sp
, &invalid_list
);
1746 kvm_mmu_commit_zap_page(kvm
, &invalid_list
);
1749 static void page_header_update_slot(struct kvm
*kvm
, void *pte
, gfn_t gfn
)
1751 int slot
= memslot_id(kvm
, gfn
);
1752 struct kvm_mmu_page
*sp
= page_header(__pa(pte
));
1754 __set_bit(slot
, sp
->slot_bitmap
);
1757 static void mmu_convert_notrap(struct kvm_mmu_page
*sp
)
1762 if (shadow_trap_nonpresent_pte
== shadow_notrap_nonpresent_pte
)
1765 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
1766 if (pt
[i
] == shadow_notrap_nonpresent_pte
)
1767 __set_spte(&pt
[i
], shadow_trap_nonpresent_pte
);
1772 * The function is based on mtrr_type_lookup() in
1773 * arch/x86/kernel/cpu/mtrr/generic.c
1775 static int get_mtrr_type(struct mtrr_state_type
*mtrr_state
,
1780 u8 prev_match
, curr_match
;
1781 int num_var_ranges
= KVM_NR_VAR_MTRR
;
1783 if (!mtrr_state
->enabled
)
1786 /* Make end inclusive end, instead of exclusive */
1789 /* Look in fixed ranges. Just return the type as per start */
1790 if (mtrr_state
->have_fixed
&& (start
< 0x100000)) {
1793 if (start
< 0x80000) {
1795 idx
+= (start
>> 16);
1796 return mtrr_state
->fixed_ranges
[idx
];
1797 } else if (start
< 0xC0000) {
1799 idx
+= ((start
- 0x80000) >> 14);
1800 return mtrr_state
->fixed_ranges
[idx
];
1801 } else if (start
< 0x1000000) {
1803 idx
+= ((start
- 0xC0000) >> 12);
1804 return mtrr_state
->fixed_ranges
[idx
];
1809 * Look in variable ranges
1810 * Look of multiple ranges matching this address and pick type
1811 * as per MTRR precedence
1813 if (!(mtrr_state
->enabled
& 2))
1814 return mtrr_state
->def_type
;
1817 for (i
= 0; i
< num_var_ranges
; ++i
) {
1818 unsigned short start_state
, end_state
;
1820 if (!(mtrr_state
->var_ranges
[i
].mask_lo
& (1 << 11)))
1823 base
= (((u64
)mtrr_state
->var_ranges
[i
].base_hi
) << 32) +
1824 (mtrr_state
->var_ranges
[i
].base_lo
& PAGE_MASK
);
1825 mask
= (((u64
)mtrr_state
->var_ranges
[i
].mask_hi
) << 32) +
1826 (mtrr_state
->var_ranges
[i
].mask_lo
& PAGE_MASK
);
1828 start_state
= ((start
& mask
) == (base
& mask
));
1829 end_state
= ((end
& mask
) == (base
& mask
));
1830 if (start_state
!= end_state
)
1833 if ((start
& mask
) != (base
& mask
))
1836 curr_match
= mtrr_state
->var_ranges
[i
].base_lo
& 0xff;
1837 if (prev_match
== 0xFF) {
1838 prev_match
= curr_match
;
1842 if (prev_match
== MTRR_TYPE_UNCACHABLE
||
1843 curr_match
== MTRR_TYPE_UNCACHABLE
)
1844 return MTRR_TYPE_UNCACHABLE
;
1846 if ((prev_match
== MTRR_TYPE_WRBACK
&&
1847 curr_match
== MTRR_TYPE_WRTHROUGH
) ||
1848 (prev_match
== MTRR_TYPE_WRTHROUGH
&&
1849 curr_match
== MTRR_TYPE_WRBACK
)) {
1850 prev_match
= MTRR_TYPE_WRTHROUGH
;
1851 curr_match
= MTRR_TYPE_WRTHROUGH
;
1854 if (prev_match
!= curr_match
)
1855 return MTRR_TYPE_UNCACHABLE
;
1858 if (prev_match
!= 0xFF)
1861 return mtrr_state
->def_type
;
1864 u8
kvm_get_guest_memory_type(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1868 mtrr
= get_mtrr_type(&vcpu
->arch
.mtrr_state
, gfn
<< PAGE_SHIFT
,
1869 (gfn
<< PAGE_SHIFT
) + PAGE_SIZE
);
1870 if (mtrr
== 0xfe || mtrr
== 0xff)
1871 mtrr
= MTRR_TYPE_WRBACK
;
1874 EXPORT_SYMBOL_GPL(kvm_get_guest_memory_type
);
1876 static void __kvm_unsync_page(struct kvm_vcpu
*vcpu
, struct kvm_mmu_page
*sp
)
1878 trace_kvm_mmu_unsync_page(sp
);
1879 ++vcpu
->kvm
->stat
.mmu_unsync
;
1882 kvm_mmu_mark_parents_unsync(sp
);
1883 mmu_convert_notrap(sp
);
1886 static void kvm_unsync_pages(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
1888 struct kvm_mmu_page
*s
;
1889 struct hlist_node
*node
;
1891 for_each_gfn_indirect_valid_sp(vcpu
->kvm
, s
, gfn
, node
) {
1894 WARN_ON(s
->role
.level
!= PT_PAGE_TABLE_LEVEL
);
1895 __kvm_unsync_page(vcpu
, s
);
1899 static int mmu_need_write_protect(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
1902 struct kvm_mmu_page
*s
;
1903 struct hlist_node
*node
;
1904 bool need_unsync
= false;
1906 for_each_gfn_indirect_valid_sp(vcpu
->kvm
, s
, gfn
, node
) {
1910 if (s
->role
.level
!= PT_PAGE_TABLE_LEVEL
)
1913 if (!need_unsync
&& !s
->unsync
) {
1920 kvm_unsync_pages(vcpu
, gfn
);
1924 static int set_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
,
1925 unsigned pte_access
, int user_fault
,
1926 int write_fault
, int level
,
1927 gfn_t gfn
, pfn_t pfn
, bool speculative
,
1928 bool can_unsync
, bool host_writable
)
1930 u64 spte
, entry
= *sptep
;
1934 * We don't set the accessed bit, since we sometimes want to see
1935 * whether the guest actually used the pte (in order to detect
1938 spte
= PT_PRESENT_MASK
;
1940 spte
|= shadow_accessed_mask
;
1942 if (pte_access
& ACC_EXEC_MASK
)
1943 spte
|= shadow_x_mask
;
1945 spte
|= shadow_nx_mask
;
1946 if (pte_access
& ACC_USER_MASK
)
1947 spte
|= shadow_user_mask
;
1948 if (level
> PT_PAGE_TABLE_LEVEL
)
1949 spte
|= PT_PAGE_SIZE_MASK
;
1951 spte
|= kvm_x86_ops
->get_mt_mask(vcpu
, gfn
,
1952 kvm_is_mmio_pfn(pfn
));
1955 spte
|= SPTE_HOST_WRITEABLE
;
1957 pte_access
&= ~ACC_WRITE_MASK
;
1959 spte
|= (u64
)pfn
<< PAGE_SHIFT
;
1961 if ((pte_access
& ACC_WRITE_MASK
)
1962 || (!vcpu
->arch
.mmu
.direct_map
&& write_fault
1963 && !is_write_protection(vcpu
) && !user_fault
)) {
1965 if (level
> PT_PAGE_TABLE_LEVEL
&&
1966 has_wrprotected_page(vcpu
->kvm
, gfn
, level
)) {
1968 drop_spte(vcpu
->kvm
, sptep
, shadow_trap_nonpresent_pte
);
1972 spte
|= PT_WRITABLE_MASK
;
1974 if (!vcpu
->arch
.mmu
.direct_map
1975 && !(pte_access
& ACC_WRITE_MASK
)) {
1976 spte
&= ~PT_USER_MASK
;
1978 * If we converted a user page to a kernel page,
1979 * so that the kernel can write to it when cr0.wp=0,
1980 * then we should prevent the kernel from executing it
1981 * if SMEP is enabled.
1983 if (kvm_read_cr4_bits(vcpu
, X86_CR4_SMEP
))
1984 spte
|= PT64_NX_MASK
;
1988 * Optimization: for pte sync, if spte was writable the hash
1989 * lookup is unnecessary (and expensive). Write protection
1990 * is responsibility of mmu_get_page / kvm_sync_page.
1991 * Same reasoning can be applied to dirty page accounting.
1993 if (!can_unsync
&& is_writable_pte(*sptep
))
1996 if (mmu_need_write_protect(vcpu
, gfn
, can_unsync
)) {
1997 pgprintk("%s: found shadow page for %llx, marking ro\n",
2000 pte_access
&= ~ACC_WRITE_MASK
;
2001 if (is_writable_pte(spte
))
2002 spte
&= ~PT_WRITABLE_MASK
;
2006 if (pte_access
& ACC_WRITE_MASK
)
2007 mark_page_dirty(vcpu
->kvm
, gfn
);
2010 update_spte(sptep
, spte
);
2012 * If we overwrite a writable spte with a read-only one we
2013 * should flush remote TLBs. Otherwise rmap_write_protect
2014 * will find a read-only spte, even though the writable spte
2015 * might be cached on a CPU's TLB.
2017 if (is_writable_pte(entry
) && !is_writable_pte(*sptep
))
2018 kvm_flush_remote_tlbs(vcpu
->kvm
);
2023 static void mmu_set_spte(struct kvm_vcpu
*vcpu
, u64
*sptep
,
2024 unsigned pt_access
, unsigned pte_access
,
2025 int user_fault
, int write_fault
,
2026 int *emulate
, int level
, gfn_t gfn
,
2027 pfn_t pfn
, bool speculative
,
2030 int was_rmapped
= 0;
2033 pgprintk("%s: spte %llx access %x write_fault %d"
2034 " user_fault %d gfn %llx\n",
2035 __func__
, *sptep
, pt_access
,
2036 write_fault
, user_fault
, gfn
);
2038 if (is_rmap_spte(*sptep
)) {
2040 * If we overwrite a PTE page pointer with a 2MB PMD, unlink
2041 * the parent of the now unreachable PTE.
2043 if (level
> PT_PAGE_TABLE_LEVEL
&&
2044 !is_large_pte(*sptep
)) {
2045 struct kvm_mmu_page
*child
;
2048 child
= page_header(pte
& PT64_BASE_ADDR_MASK
);
2049 drop_parent_pte(child
, sptep
);
2050 kvm_flush_remote_tlbs(vcpu
->kvm
);
2051 } else if (pfn
!= spte_to_pfn(*sptep
)) {
2052 pgprintk("hfn old %llx new %llx\n",
2053 spte_to_pfn(*sptep
), pfn
);
2054 drop_spte(vcpu
->kvm
, sptep
, shadow_trap_nonpresent_pte
);
2055 kvm_flush_remote_tlbs(vcpu
->kvm
);
2060 if (set_spte(vcpu
, sptep
, pte_access
, user_fault
, write_fault
,
2061 level
, gfn
, pfn
, speculative
, true,
2065 kvm_mmu_flush_tlb(vcpu
);
2068 pgprintk("%s: setting spte %llx\n", __func__
, *sptep
);
2069 pgprintk("instantiating %s PTE (%s) at %llx (%llx) addr %p\n",
2070 is_large_pte(*sptep
)? "2MB" : "4kB",
2071 *sptep
& PT_PRESENT_MASK
?"RW":"R", gfn
,
2073 if (!was_rmapped
&& is_large_pte(*sptep
))
2074 ++vcpu
->kvm
->stat
.lpages
;
2076 if (is_shadow_present_pte(*sptep
)) {
2077 page_header_update_slot(vcpu
->kvm
, sptep
, gfn
);
2079 rmap_count
= rmap_add(vcpu
, sptep
, gfn
);
2080 if (rmap_count
> RMAP_RECYCLE_THRESHOLD
)
2081 rmap_recycle(vcpu
, sptep
, gfn
);
2084 kvm_release_pfn_clean(pfn
);
2086 vcpu
->arch
.last_pte_updated
= sptep
;
2087 vcpu
->arch
.last_pte_gfn
= gfn
;
2091 static void nonpaging_new_cr3(struct kvm_vcpu
*vcpu
)
2095 static pfn_t
pte_prefetch_gfn_to_pfn(struct kvm_vcpu
*vcpu
, gfn_t gfn
,
2098 struct kvm_memory_slot
*slot
;
2101 slot
= gfn_to_memslot_dirty_bitmap(vcpu
, gfn
, no_dirty_log
);
2104 return page_to_pfn(bad_page
);
2107 hva
= gfn_to_hva_memslot(slot
, gfn
);
2109 return hva_to_pfn_atomic(vcpu
->kvm
, hva
);
2112 static int direct_pte_prefetch_many(struct kvm_vcpu
*vcpu
,
2113 struct kvm_mmu_page
*sp
,
2114 u64
*start
, u64
*end
)
2116 struct page
*pages
[PTE_PREFETCH_NUM
];
2117 unsigned access
= sp
->role
.access
;
2121 gfn
= kvm_mmu_page_get_gfn(sp
, start
- sp
->spt
);
2122 if (!gfn_to_memslot_dirty_bitmap(vcpu
, gfn
, access
& ACC_WRITE_MASK
))
2125 ret
= gfn_to_page_many_atomic(vcpu
->kvm
, gfn
, pages
, end
- start
);
2129 for (i
= 0; i
< ret
; i
++, gfn
++, start
++)
2130 mmu_set_spte(vcpu
, start
, ACC_ALL
,
2132 sp
->role
.level
, gfn
,
2133 page_to_pfn(pages
[i
]), true, true);
2138 static void __direct_pte_prefetch(struct kvm_vcpu
*vcpu
,
2139 struct kvm_mmu_page
*sp
, u64
*sptep
)
2141 u64
*spte
, *start
= NULL
;
2144 WARN_ON(!sp
->role
.direct
);
2146 i
= (sptep
- sp
->spt
) & ~(PTE_PREFETCH_NUM
- 1);
2149 for (i
= 0; i
< PTE_PREFETCH_NUM
; i
++, spte
++) {
2150 if (*spte
!= shadow_trap_nonpresent_pte
|| spte
== sptep
) {
2153 if (direct_pte_prefetch_many(vcpu
, sp
, start
, spte
) < 0)
2161 static void direct_pte_prefetch(struct kvm_vcpu
*vcpu
, u64
*sptep
)
2163 struct kvm_mmu_page
*sp
;
2166 * Since it's no accessed bit on EPT, it's no way to
2167 * distinguish between actually accessed translations
2168 * and prefetched, so disable pte prefetch if EPT is
2171 if (!shadow_accessed_mask
)
2174 sp
= page_header(__pa(sptep
));
2175 if (sp
->role
.level
> PT_PAGE_TABLE_LEVEL
)
2178 __direct_pte_prefetch(vcpu
, sp
, sptep
);
2181 static int __direct_map(struct kvm_vcpu
*vcpu
, gpa_t v
, int write
,
2182 int map_writable
, int level
, gfn_t gfn
, pfn_t pfn
,
2185 struct kvm_shadow_walk_iterator iterator
;
2186 struct kvm_mmu_page
*sp
;
2190 for_each_shadow_entry(vcpu
, (u64
)gfn
<< PAGE_SHIFT
, iterator
) {
2191 if (iterator
.level
== level
) {
2192 unsigned pte_access
= ACC_ALL
;
2194 mmu_set_spte(vcpu
, iterator
.sptep
, ACC_ALL
, pte_access
,
2196 level
, gfn
, pfn
, prefault
, map_writable
);
2197 direct_pte_prefetch(vcpu
, iterator
.sptep
);
2198 ++vcpu
->stat
.pf_fixed
;
2202 if (*iterator
.sptep
== shadow_trap_nonpresent_pte
) {
2203 u64 base_addr
= iterator
.addr
;
2205 base_addr
&= PT64_LVL_ADDR_MASK(iterator
.level
);
2206 pseudo_gfn
= base_addr
>> PAGE_SHIFT
;
2207 sp
= kvm_mmu_get_page(vcpu
, pseudo_gfn
, iterator
.addr
,
2209 1, ACC_ALL
, iterator
.sptep
);
2211 pgprintk("nonpaging_map: ENOMEM\n");
2212 kvm_release_pfn_clean(pfn
);
2216 __set_spte(iterator
.sptep
,
2218 | PT_PRESENT_MASK
| PT_WRITABLE_MASK
2219 | shadow_user_mask
| shadow_x_mask
2220 | shadow_accessed_mask
);
2226 static void kvm_send_hwpoison_signal(unsigned long address
, struct task_struct
*tsk
)
2230 info
.si_signo
= SIGBUS
;
2232 info
.si_code
= BUS_MCEERR_AR
;
2233 info
.si_addr
= (void __user
*)address
;
2234 info
.si_addr_lsb
= PAGE_SHIFT
;
2236 send_sig_info(SIGBUS
, &info
, tsk
);
2239 static int kvm_handle_bad_page(struct kvm_vcpu
*vcpu
, gva_t gva
,
2240 unsigned access
, gfn_t gfn
, pfn_t pfn
)
2242 kvm_release_pfn_clean(pfn
);
2243 if (is_hwpoison_pfn(pfn
)) {
2244 kvm_send_hwpoison_signal(gfn_to_hva(vcpu
->kvm
, gfn
), current
);
2246 } else if (is_fault_pfn(pfn
))
2249 vcpu_cache_mmio_info(vcpu
, gva
, gfn
, access
);
2253 static void transparent_hugepage_adjust(struct kvm_vcpu
*vcpu
,
2254 gfn_t
*gfnp
, pfn_t
*pfnp
, int *levelp
)
2258 int level
= *levelp
;
2261 * Check if it's a transparent hugepage. If this would be an
2262 * hugetlbfs page, level wouldn't be set to
2263 * PT_PAGE_TABLE_LEVEL and there would be no adjustment done
2266 if (!is_error_pfn(pfn
) && !kvm_is_mmio_pfn(pfn
) &&
2267 level
== PT_PAGE_TABLE_LEVEL
&&
2268 PageTransCompound(pfn_to_page(pfn
)) &&
2269 !has_wrprotected_page(vcpu
->kvm
, gfn
, PT_DIRECTORY_LEVEL
)) {
2272 * mmu_notifier_retry was successful and we hold the
2273 * mmu_lock here, so the pmd can't become splitting
2274 * from under us, and in turn
2275 * __split_huge_page_refcount() can't run from under
2276 * us and we can safely transfer the refcount from
2277 * PG_tail to PG_head as we switch the pfn to tail to
2280 *levelp
= level
= PT_DIRECTORY_LEVEL
;
2281 mask
= KVM_PAGES_PER_HPAGE(level
) - 1;
2282 VM_BUG_ON((gfn
& mask
) != (pfn
& mask
));
2286 kvm_release_pfn_clean(pfn
);
2288 if (!get_page_unless_zero(pfn_to_page(pfn
)))
2295 static bool try_async_pf(struct kvm_vcpu
*vcpu
, bool prefault
, gfn_t gfn
,
2296 gva_t gva
, pfn_t
*pfn
, bool write
, bool *writable
);
2298 static int nonpaging_map(struct kvm_vcpu
*vcpu
, gva_t v
, int write
, gfn_t gfn
,
2305 unsigned long mmu_seq
;
2308 force_pt_level
= mapping_level_dirty_bitmap(vcpu
, gfn
);
2309 if (likely(!force_pt_level
)) {
2310 level
= mapping_level(vcpu
, gfn
);
2312 * This path builds a PAE pagetable - so we can map
2313 * 2mb pages at maximum. Therefore check if the level
2314 * is larger than that.
2316 if (level
> PT_DIRECTORY_LEVEL
)
2317 level
= PT_DIRECTORY_LEVEL
;
2319 gfn
&= ~(KVM_PAGES_PER_HPAGE(level
) - 1);
2321 level
= PT_PAGE_TABLE_LEVEL
;
2323 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2326 if (try_async_pf(vcpu
, prefault
, gfn
, v
, &pfn
, write
, &map_writable
))
2330 if (is_error_pfn(pfn
))
2331 return kvm_handle_bad_page(vcpu
, v
, ACC_ALL
, gfn
, pfn
);
2333 spin_lock(&vcpu
->kvm
->mmu_lock
);
2334 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2336 kvm_mmu_free_some_pages(vcpu
);
2337 if (likely(!force_pt_level
))
2338 transparent_hugepage_adjust(vcpu
, &gfn
, &pfn
, &level
);
2339 r
= __direct_map(vcpu
, v
, write
, map_writable
, level
, gfn
, pfn
,
2341 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2347 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2348 kvm_release_pfn_clean(pfn
);
2353 static void mmu_free_roots(struct kvm_vcpu
*vcpu
)
2356 struct kvm_mmu_page
*sp
;
2357 LIST_HEAD(invalid_list
);
2359 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2361 spin_lock(&vcpu
->kvm
->mmu_lock
);
2362 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
&&
2363 (vcpu
->arch
.mmu
.root_level
== PT64_ROOT_LEVEL
||
2364 vcpu
->arch
.mmu
.direct_map
)) {
2365 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2367 sp
= page_header(root
);
2369 if (!sp
->root_count
&& sp
->role
.invalid
) {
2370 kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
, &invalid_list
);
2371 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
2373 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2374 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2377 for (i
= 0; i
< 4; ++i
) {
2378 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2381 root
&= PT64_BASE_ADDR_MASK
;
2382 sp
= page_header(root
);
2384 if (!sp
->root_count
&& sp
->role
.invalid
)
2385 kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
,
2388 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
2390 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
2391 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2392 vcpu
->arch
.mmu
.root_hpa
= INVALID_PAGE
;
2395 static int mmu_check_root(struct kvm_vcpu
*vcpu
, gfn_t root_gfn
)
2399 if (!kvm_is_visible_gfn(vcpu
->kvm
, root_gfn
)) {
2400 kvm_make_request(KVM_REQ_TRIPLE_FAULT
, vcpu
);
2407 static int mmu_alloc_direct_roots(struct kvm_vcpu
*vcpu
)
2409 struct kvm_mmu_page
*sp
;
2412 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2413 spin_lock(&vcpu
->kvm
->mmu_lock
);
2414 kvm_mmu_free_some_pages(vcpu
);
2415 sp
= kvm_mmu_get_page(vcpu
, 0, 0, PT64_ROOT_LEVEL
,
2418 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2419 vcpu
->arch
.mmu
.root_hpa
= __pa(sp
->spt
);
2420 } else if (vcpu
->arch
.mmu
.shadow_root_level
== PT32E_ROOT_LEVEL
) {
2421 for (i
= 0; i
< 4; ++i
) {
2422 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2424 ASSERT(!VALID_PAGE(root
));
2425 spin_lock(&vcpu
->kvm
->mmu_lock
);
2426 kvm_mmu_free_some_pages(vcpu
);
2427 sp
= kvm_mmu_get_page(vcpu
, i
<< (30 - PAGE_SHIFT
),
2429 PT32_ROOT_LEVEL
, 1, ACC_ALL
,
2431 root
= __pa(sp
->spt
);
2433 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2434 vcpu
->arch
.mmu
.pae_root
[i
] = root
| PT_PRESENT_MASK
;
2436 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
2443 static int mmu_alloc_shadow_roots(struct kvm_vcpu
*vcpu
)
2445 struct kvm_mmu_page
*sp
;
2450 root_gfn
= vcpu
->arch
.mmu
.get_cr3(vcpu
) >> PAGE_SHIFT
;
2452 if (mmu_check_root(vcpu
, root_gfn
))
2456 * Do we shadow a long mode page table? If so we need to
2457 * write-protect the guests page table root.
2459 if (vcpu
->arch
.mmu
.root_level
== PT64_ROOT_LEVEL
) {
2460 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2462 ASSERT(!VALID_PAGE(root
));
2464 spin_lock(&vcpu
->kvm
->mmu_lock
);
2465 kvm_mmu_free_some_pages(vcpu
);
2466 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, 0, PT64_ROOT_LEVEL
,
2468 root
= __pa(sp
->spt
);
2470 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2471 vcpu
->arch
.mmu
.root_hpa
= root
;
2476 * We shadow a 32 bit page table. This may be a legacy 2-level
2477 * or a PAE 3-level page table. In either case we need to be aware that
2478 * the shadow page table may be a PAE or a long mode page table.
2480 pm_mask
= PT_PRESENT_MASK
;
2481 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
)
2482 pm_mask
|= PT_ACCESSED_MASK
| PT_WRITABLE_MASK
| PT_USER_MASK
;
2484 for (i
= 0; i
< 4; ++i
) {
2485 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2487 ASSERT(!VALID_PAGE(root
));
2488 if (vcpu
->arch
.mmu
.root_level
== PT32E_ROOT_LEVEL
) {
2489 pdptr
= kvm_pdptr_read_mmu(vcpu
, &vcpu
->arch
.mmu
, i
);
2490 if (!is_present_gpte(pdptr
)) {
2491 vcpu
->arch
.mmu
.pae_root
[i
] = 0;
2494 root_gfn
= pdptr
>> PAGE_SHIFT
;
2495 if (mmu_check_root(vcpu
, root_gfn
))
2498 spin_lock(&vcpu
->kvm
->mmu_lock
);
2499 kvm_mmu_free_some_pages(vcpu
);
2500 sp
= kvm_mmu_get_page(vcpu
, root_gfn
, i
<< 30,
2503 root
= __pa(sp
->spt
);
2505 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2507 vcpu
->arch
.mmu
.pae_root
[i
] = root
| pm_mask
;
2509 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.pae_root
);
2512 * If we shadow a 32 bit page table with a long mode page
2513 * table we enter this path.
2515 if (vcpu
->arch
.mmu
.shadow_root_level
== PT64_ROOT_LEVEL
) {
2516 if (vcpu
->arch
.mmu
.lm_root
== NULL
) {
2518 * The additional page necessary for this is only
2519 * allocated on demand.
2524 lm_root
= (void*)get_zeroed_page(GFP_KERNEL
);
2525 if (lm_root
== NULL
)
2528 lm_root
[0] = __pa(vcpu
->arch
.mmu
.pae_root
) | pm_mask
;
2530 vcpu
->arch
.mmu
.lm_root
= lm_root
;
2533 vcpu
->arch
.mmu
.root_hpa
= __pa(vcpu
->arch
.mmu
.lm_root
);
2539 static int mmu_alloc_roots(struct kvm_vcpu
*vcpu
)
2541 if (vcpu
->arch
.mmu
.direct_map
)
2542 return mmu_alloc_direct_roots(vcpu
);
2544 return mmu_alloc_shadow_roots(vcpu
);
2547 static void mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2550 struct kvm_mmu_page
*sp
;
2552 if (vcpu
->arch
.mmu
.direct_map
)
2555 if (!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
2558 vcpu_clear_mmio_info(vcpu
, ~0ul);
2559 trace_kvm_mmu_audit(vcpu
, AUDIT_PRE_SYNC
);
2560 if (vcpu
->arch
.mmu
.root_level
== PT64_ROOT_LEVEL
) {
2561 hpa_t root
= vcpu
->arch
.mmu
.root_hpa
;
2562 sp
= page_header(root
);
2563 mmu_sync_children(vcpu
, sp
);
2564 trace_kvm_mmu_audit(vcpu
, AUDIT_POST_SYNC
);
2567 for (i
= 0; i
< 4; ++i
) {
2568 hpa_t root
= vcpu
->arch
.mmu
.pae_root
[i
];
2570 if (root
&& VALID_PAGE(root
)) {
2571 root
&= PT64_BASE_ADDR_MASK
;
2572 sp
= page_header(root
);
2573 mmu_sync_children(vcpu
, sp
);
2576 trace_kvm_mmu_audit(vcpu
, AUDIT_POST_SYNC
);
2579 void kvm_mmu_sync_roots(struct kvm_vcpu
*vcpu
)
2581 spin_lock(&vcpu
->kvm
->mmu_lock
);
2582 mmu_sync_roots(vcpu
);
2583 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2586 static gpa_t
nonpaging_gva_to_gpa(struct kvm_vcpu
*vcpu
, gva_t vaddr
,
2587 u32 access
, struct x86_exception
*exception
)
2590 exception
->error_code
= 0;
2594 static gpa_t
nonpaging_gva_to_gpa_nested(struct kvm_vcpu
*vcpu
, gva_t vaddr
,
2596 struct x86_exception
*exception
)
2599 exception
->error_code
= 0;
2600 return vcpu
->arch
.nested_mmu
.translate_gpa(vcpu
, vaddr
, access
);
2603 static int nonpaging_page_fault(struct kvm_vcpu
*vcpu
, gva_t gva
,
2604 u32 error_code
, bool prefault
)
2609 pgprintk("%s: gva %lx error %x\n", __func__
, gva
, error_code
);
2610 r
= mmu_topup_memory_caches(vcpu
);
2615 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2617 gfn
= gva
>> PAGE_SHIFT
;
2619 return nonpaging_map(vcpu
, gva
& PAGE_MASK
,
2620 error_code
& PFERR_WRITE_MASK
, gfn
, prefault
);
2623 static int kvm_arch_setup_async_pf(struct kvm_vcpu
*vcpu
, gva_t gva
, gfn_t gfn
)
2625 struct kvm_arch_async_pf arch
;
2627 arch
.token
= (vcpu
->arch
.apf
.id
++ << 12) | vcpu
->vcpu_id
;
2629 arch
.direct_map
= vcpu
->arch
.mmu
.direct_map
;
2630 arch
.cr3
= vcpu
->arch
.mmu
.get_cr3(vcpu
);
2632 return kvm_setup_async_pf(vcpu
, gva
, gfn
, &arch
);
2635 static bool can_do_async_pf(struct kvm_vcpu
*vcpu
)
2637 if (unlikely(!irqchip_in_kernel(vcpu
->kvm
) ||
2638 kvm_event_needs_reinjection(vcpu
)))
2641 return kvm_x86_ops
->interrupt_allowed(vcpu
);
2644 static bool try_async_pf(struct kvm_vcpu
*vcpu
, bool prefault
, gfn_t gfn
,
2645 gva_t gva
, pfn_t
*pfn
, bool write
, bool *writable
)
2649 *pfn
= gfn_to_pfn_async(vcpu
->kvm
, gfn
, &async
, write
, writable
);
2652 return false; /* *pfn has correct page already */
2654 put_page(pfn_to_page(*pfn
));
2656 if (!prefault
&& can_do_async_pf(vcpu
)) {
2657 trace_kvm_try_async_get_page(gva
, gfn
);
2658 if (kvm_find_async_pf_gfn(vcpu
, gfn
)) {
2659 trace_kvm_async_pf_doublefault(gva
, gfn
);
2660 kvm_make_request(KVM_REQ_APF_HALT
, vcpu
);
2662 } else if (kvm_arch_setup_async_pf(vcpu
, gva
, gfn
))
2666 *pfn
= gfn_to_pfn_prot(vcpu
->kvm
, gfn
, write
, writable
);
2671 static int tdp_page_fault(struct kvm_vcpu
*vcpu
, gva_t gpa
, u32 error_code
,
2678 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
2679 unsigned long mmu_seq
;
2680 int write
= error_code
& PFERR_WRITE_MASK
;
2684 ASSERT(VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2686 r
= mmu_topup_memory_caches(vcpu
);
2690 force_pt_level
= mapping_level_dirty_bitmap(vcpu
, gfn
);
2691 if (likely(!force_pt_level
)) {
2692 level
= mapping_level(vcpu
, gfn
);
2693 gfn
&= ~(KVM_PAGES_PER_HPAGE(level
) - 1);
2695 level
= PT_PAGE_TABLE_LEVEL
;
2697 mmu_seq
= vcpu
->kvm
->mmu_notifier_seq
;
2700 if (try_async_pf(vcpu
, prefault
, gfn
, gpa
, &pfn
, write
, &map_writable
))
2704 if (is_error_pfn(pfn
))
2705 return kvm_handle_bad_page(vcpu
, 0, 0, gfn
, pfn
);
2706 spin_lock(&vcpu
->kvm
->mmu_lock
);
2707 if (mmu_notifier_retry(vcpu
, mmu_seq
))
2709 kvm_mmu_free_some_pages(vcpu
);
2710 if (likely(!force_pt_level
))
2711 transparent_hugepage_adjust(vcpu
, &gfn
, &pfn
, &level
);
2712 r
= __direct_map(vcpu
, gpa
, write
, map_writable
,
2713 level
, gfn
, pfn
, prefault
);
2714 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2719 spin_unlock(&vcpu
->kvm
->mmu_lock
);
2720 kvm_release_pfn_clean(pfn
);
2724 static void nonpaging_free(struct kvm_vcpu
*vcpu
)
2726 mmu_free_roots(vcpu
);
2729 static int nonpaging_init_context(struct kvm_vcpu
*vcpu
,
2730 struct kvm_mmu
*context
)
2732 context
->new_cr3
= nonpaging_new_cr3
;
2733 context
->page_fault
= nonpaging_page_fault
;
2734 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2735 context
->free
= nonpaging_free
;
2736 context
->prefetch_page
= nonpaging_prefetch_page
;
2737 context
->sync_page
= nonpaging_sync_page
;
2738 context
->invlpg
= nonpaging_invlpg
;
2739 context
->update_pte
= nonpaging_update_pte
;
2740 context
->root_level
= 0;
2741 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2742 context
->root_hpa
= INVALID_PAGE
;
2743 context
->direct_map
= true;
2744 context
->nx
= false;
2748 void kvm_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
2750 ++vcpu
->stat
.tlb_flush
;
2751 kvm_make_request(KVM_REQ_TLB_FLUSH
, vcpu
);
2754 static void paging_new_cr3(struct kvm_vcpu
*vcpu
)
2756 pgprintk("%s: cr3 %lx\n", __func__
, kvm_read_cr3(vcpu
));
2757 mmu_free_roots(vcpu
);
2760 static unsigned long get_cr3(struct kvm_vcpu
*vcpu
)
2762 return kvm_read_cr3(vcpu
);
2765 static void inject_page_fault(struct kvm_vcpu
*vcpu
,
2766 struct x86_exception
*fault
)
2768 vcpu
->arch
.mmu
.inject_page_fault(vcpu
, fault
);
2771 static void paging_free(struct kvm_vcpu
*vcpu
)
2773 nonpaging_free(vcpu
);
2776 static bool is_rsvd_bits_set(struct kvm_mmu
*mmu
, u64 gpte
, int level
)
2780 bit7
= (gpte
>> 7) & 1;
2781 return (gpte
& mmu
->rsvd_bits_mask
[bit7
][level
-1]) != 0;
2785 #include "paging_tmpl.h"
2789 #include "paging_tmpl.h"
2792 static void reset_rsvds_bits_mask(struct kvm_vcpu
*vcpu
,
2793 struct kvm_mmu
*context
,
2796 int maxphyaddr
= cpuid_maxphyaddr(vcpu
);
2797 u64 exb_bit_rsvd
= 0;
2800 exb_bit_rsvd
= rsvd_bits(63, 63);
2802 case PT32_ROOT_LEVEL
:
2803 /* no rsvd bits for 2 level 4K page table entries */
2804 context
->rsvd_bits_mask
[0][1] = 0;
2805 context
->rsvd_bits_mask
[0][0] = 0;
2806 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[0][0];
2808 if (!is_pse(vcpu
)) {
2809 context
->rsvd_bits_mask
[1][1] = 0;
2813 if (is_cpuid_PSE36())
2814 /* 36bits PSE 4MB page */
2815 context
->rsvd_bits_mask
[1][1] = rsvd_bits(17, 21);
2817 /* 32 bits PSE 4MB page */
2818 context
->rsvd_bits_mask
[1][1] = rsvd_bits(13, 21);
2820 case PT32E_ROOT_LEVEL
:
2821 context
->rsvd_bits_mask
[0][2] =
2822 rsvd_bits(maxphyaddr
, 63) |
2823 rsvd_bits(7, 8) | rsvd_bits(1, 2); /* PDPTE */
2824 context
->rsvd_bits_mask
[0][1] = exb_bit_rsvd
|
2825 rsvd_bits(maxphyaddr
, 62); /* PDE */
2826 context
->rsvd_bits_mask
[0][0] = exb_bit_rsvd
|
2827 rsvd_bits(maxphyaddr
, 62); /* PTE */
2828 context
->rsvd_bits_mask
[1][1] = exb_bit_rsvd
|
2829 rsvd_bits(maxphyaddr
, 62) |
2830 rsvd_bits(13, 20); /* large page */
2831 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[0][0];
2833 case PT64_ROOT_LEVEL
:
2834 context
->rsvd_bits_mask
[0][3] = exb_bit_rsvd
|
2835 rsvd_bits(maxphyaddr
, 51) | rsvd_bits(7, 8);
2836 context
->rsvd_bits_mask
[0][2] = exb_bit_rsvd
|
2837 rsvd_bits(maxphyaddr
, 51) | rsvd_bits(7, 8);
2838 context
->rsvd_bits_mask
[0][1] = exb_bit_rsvd
|
2839 rsvd_bits(maxphyaddr
, 51);
2840 context
->rsvd_bits_mask
[0][0] = exb_bit_rsvd
|
2841 rsvd_bits(maxphyaddr
, 51);
2842 context
->rsvd_bits_mask
[1][3] = context
->rsvd_bits_mask
[0][3];
2843 context
->rsvd_bits_mask
[1][2] = exb_bit_rsvd
|
2844 rsvd_bits(maxphyaddr
, 51) |
2846 context
->rsvd_bits_mask
[1][1] = exb_bit_rsvd
|
2847 rsvd_bits(maxphyaddr
, 51) |
2848 rsvd_bits(13, 20); /* large page */
2849 context
->rsvd_bits_mask
[1][0] = context
->rsvd_bits_mask
[0][0];
2854 static int paging64_init_context_common(struct kvm_vcpu
*vcpu
,
2855 struct kvm_mmu
*context
,
2858 context
->nx
= is_nx(vcpu
);
2860 reset_rsvds_bits_mask(vcpu
, context
, level
);
2862 ASSERT(is_pae(vcpu
));
2863 context
->new_cr3
= paging_new_cr3
;
2864 context
->page_fault
= paging64_page_fault
;
2865 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2866 context
->prefetch_page
= paging64_prefetch_page
;
2867 context
->sync_page
= paging64_sync_page
;
2868 context
->invlpg
= paging64_invlpg
;
2869 context
->update_pte
= paging64_update_pte
;
2870 context
->free
= paging_free
;
2871 context
->root_level
= level
;
2872 context
->shadow_root_level
= level
;
2873 context
->root_hpa
= INVALID_PAGE
;
2874 context
->direct_map
= false;
2878 static int paging64_init_context(struct kvm_vcpu
*vcpu
,
2879 struct kvm_mmu
*context
)
2881 return paging64_init_context_common(vcpu
, context
, PT64_ROOT_LEVEL
);
2884 static int paging32_init_context(struct kvm_vcpu
*vcpu
,
2885 struct kvm_mmu
*context
)
2887 context
->nx
= false;
2889 reset_rsvds_bits_mask(vcpu
, context
, PT32_ROOT_LEVEL
);
2891 context
->new_cr3
= paging_new_cr3
;
2892 context
->page_fault
= paging32_page_fault
;
2893 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2894 context
->free
= paging_free
;
2895 context
->prefetch_page
= paging32_prefetch_page
;
2896 context
->sync_page
= paging32_sync_page
;
2897 context
->invlpg
= paging32_invlpg
;
2898 context
->update_pte
= paging32_update_pte
;
2899 context
->root_level
= PT32_ROOT_LEVEL
;
2900 context
->shadow_root_level
= PT32E_ROOT_LEVEL
;
2901 context
->root_hpa
= INVALID_PAGE
;
2902 context
->direct_map
= false;
2906 static int paging32E_init_context(struct kvm_vcpu
*vcpu
,
2907 struct kvm_mmu
*context
)
2909 return paging64_init_context_common(vcpu
, context
, PT32E_ROOT_LEVEL
);
2912 static int init_kvm_tdp_mmu(struct kvm_vcpu
*vcpu
)
2914 struct kvm_mmu
*context
= vcpu
->arch
.walk_mmu
;
2916 context
->base_role
.word
= 0;
2917 context
->new_cr3
= nonpaging_new_cr3
;
2918 context
->page_fault
= tdp_page_fault
;
2919 context
->free
= nonpaging_free
;
2920 context
->prefetch_page
= nonpaging_prefetch_page
;
2921 context
->sync_page
= nonpaging_sync_page
;
2922 context
->invlpg
= nonpaging_invlpg
;
2923 context
->update_pte
= nonpaging_update_pte
;
2924 context
->shadow_root_level
= kvm_x86_ops
->get_tdp_level();
2925 context
->root_hpa
= INVALID_PAGE
;
2926 context
->direct_map
= true;
2927 context
->set_cr3
= kvm_x86_ops
->set_tdp_cr3
;
2928 context
->get_cr3
= get_cr3
;
2929 context
->inject_page_fault
= kvm_inject_page_fault
;
2930 context
->nx
= is_nx(vcpu
);
2932 if (!is_paging(vcpu
)) {
2933 context
->nx
= false;
2934 context
->gva_to_gpa
= nonpaging_gva_to_gpa
;
2935 context
->root_level
= 0;
2936 } else if (is_long_mode(vcpu
)) {
2937 context
->nx
= is_nx(vcpu
);
2938 reset_rsvds_bits_mask(vcpu
, context
, PT64_ROOT_LEVEL
);
2939 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2940 context
->root_level
= PT64_ROOT_LEVEL
;
2941 } else if (is_pae(vcpu
)) {
2942 context
->nx
= is_nx(vcpu
);
2943 reset_rsvds_bits_mask(vcpu
, context
, PT32E_ROOT_LEVEL
);
2944 context
->gva_to_gpa
= paging64_gva_to_gpa
;
2945 context
->root_level
= PT32E_ROOT_LEVEL
;
2947 context
->nx
= false;
2948 reset_rsvds_bits_mask(vcpu
, context
, PT32_ROOT_LEVEL
);
2949 context
->gva_to_gpa
= paging32_gva_to_gpa
;
2950 context
->root_level
= PT32_ROOT_LEVEL
;
2956 int kvm_init_shadow_mmu(struct kvm_vcpu
*vcpu
, struct kvm_mmu
*context
)
2959 bool smep
= kvm_read_cr4_bits(vcpu
, X86_CR4_SMEP
);
2961 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
2963 if (!is_paging(vcpu
))
2964 r
= nonpaging_init_context(vcpu
, context
);
2965 else if (is_long_mode(vcpu
))
2966 r
= paging64_init_context(vcpu
, context
);
2967 else if (is_pae(vcpu
))
2968 r
= paging32E_init_context(vcpu
, context
);
2970 r
= paging32_init_context(vcpu
, context
);
2972 vcpu
->arch
.mmu
.base_role
.cr4_pae
= !!is_pae(vcpu
);
2973 vcpu
->arch
.mmu
.base_role
.cr0_wp
= is_write_protection(vcpu
);
2974 vcpu
->arch
.mmu
.base_role
.smep_andnot_wp
2975 = smep
&& !is_write_protection(vcpu
);
2979 EXPORT_SYMBOL_GPL(kvm_init_shadow_mmu
);
2981 static int init_kvm_softmmu(struct kvm_vcpu
*vcpu
)
2983 int r
= kvm_init_shadow_mmu(vcpu
, vcpu
->arch
.walk_mmu
);
2985 vcpu
->arch
.walk_mmu
->set_cr3
= kvm_x86_ops
->set_cr3
;
2986 vcpu
->arch
.walk_mmu
->get_cr3
= get_cr3
;
2987 vcpu
->arch
.walk_mmu
->inject_page_fault
= kvm_inject_page_fault
;
2992 static int init_kvm_nested_mmu(struct kvm_vcpu
*vcpu
)
2994 struct kvm_mmu
*g_context
= &vcpu
->arch
.nested_mmu
;
2996 g_context
->get_cr3
= get_cr3
;
2997 g_context
->inject_page_fault
= kvm_inject_page_fault
;
3000 * Note that arch.mmu.gva_to_gpa translates l2_gva to l1_gpa. The
3001 * translation of l2_gpa to l1_gpa addresses is done using the
3002 * arch.nested_mmu.gva_to_gpa function. Basically the gva_to_gpa
3003 * functions between mmu and nested_mmu are swapped.
3005 if (!is_paging(vcpu
)) {
3006 g_context
->nx
= false;
3007 g_context
->root_level
= 0;
3008 g_context
->gva_to_gpa
= nonpaging_gva_to_gpa_nested
;
3009 } else if (is_long_mode(vcpu
)) {
3010 g_context
->nx
= is_nx(vcpu
);
3011 reset_rsvds_bits_mask(vcpu
, g_context
, PT64_ROOT_LEVEL
);
3012 g_context
->root_level
= PT64_ROOT_LEVEL
;
3013 g_context
->gva_to_gpa
= paging64_gva_to_gpa_nested
;
3014 } else if (is_pae(vcpu
)) {
3015 g_context
->nx
= is_nx(vcpu
);
3016 reset_rsvds_bits_mask(vcpu
, g_context
, PT32E_ROOT_LEVEL
);
3017 g_context
->root_level
= PT32E_ROOT_LEVEL
;
3018 g_context
->gva_to_gpa
= paging64_gva_to_gpa_nested
;
3020 g_context
->nx
= false;
3021 reset_rsvds_bits_mask(vcpu
, g_context
, PT32_ROOT_LEVEL
);
3022 g_context
->root_level
= PT32_ROOT_LEVEL
;
3023 g_context
->gva_to_gpa
= paging32_gva_to_gpa_nested
;
3029 static int init_kvm_mmu(struct kvm_vcpu
*vcpu
)
3031 if (mmu_is_nested(vcpu
))
3032 return init_kvm_nested_mmu(vcpu
);
3033 else if (tdp_enabled
)
3034 return init_kvm_tdp_mmu(vcpu
);
3036 return init_kvm_softmmu(vcpu
);
3039 static void destroy_kvm_mmu(struct kvm_vcpu
*vcpu
)
3042 if (VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
))
3043 /* mmu.free() should set root_hpa = INVALID_PAGE */
3044 vcpu
->arch
.mmu
.free(vcpu
);
3047 int kvm_mmu_reset_context(struct kvm_vcpu
*vcpu
)
3049 destroy_kvm_mmu(vcpu
);
3050 return init_kvm_mmu(vcpu
);
3052 EXPORT_SYMBOL_GPL(kvm_mmu_reset_context
);
3054 int kvm_mmu_load(struct kvm_vcpu
*vcpu
)
3058 r
= mmu_topup_memory_caches(vcpu
);
3061 r
= mmu_alloc_roots(vcpu
);
3062 spin_lock(&vcpu
->kvm
->mmu_lock
);
3063 mmu_sync_roots(vcpu
);
3064 spin_unlock(&vcpu
->kvm
->mmu_lock
);
3067 /* set_cr3() should ensure TLB has been flushed */
3068 vcpu
->arch
.mmu
.set_cr3(vcpu
, vcpu
->arch
.mmu
.root_hpa
);
3072 EXPORT_SYMBOL_GPL(kvm_mmu_load
);
3074 void kvm_mmu_unload(struct kvm_vcpu
*vcpu
)
3076 mmu_free_roots(vcpu
);
3078 EXPORT_SYMBOL_GPL(kvm_mmu_unload
);
3080 static void mmu_pte_write_new_pte(struct kvm_vcpu
*vcpu
,
3081 struct kvm_mmu_page
*sp
, u64
*spte
,
3084 if (sp
->role
.level
!= PT_PAGE_TABLE_LEVEL
) {
3085 ++vcpu
->kvm
->stat
.mmu_pde_zapped
;
3089 ++vcpu
->kvm
->stat
.mmu_pte_updated
;
3090 vcpu
->arch
.mmu
.update_pte(vcpu
, sp
, spte
, new);
3093 static bool need_remote_flush(u64 old
, u64
new)
3095 if (!is_shadow_present_pte(old
))
3097 if (!is_shadow_present_pte(new))
3099 if ((old
^ new) & PT64_BASE_ADDR_MASK
)
3101 old
^= PT64_NX_MASK
;
3102 new ^= PT64_NX_MASK
;
3103 return (old
& ~new & PT64_PERM_MASK
) != 0;
3106 static void mmu_pte_write_flush_tlb(struct kvm_vcpu
*vcpu
, bool zap_page
,
3107 bool remote_flush
, bool local_flush
)
3113 kvm_flush_remote_tlbs(vcpu
->kvm
);
3114 else if (local_flush
)
3115 kvm_mmu_flush_tlb(vcpu
);
3118 static bool last_updated_pte_accessed(struct kvm_vcpu
*vcpu
)
3120 u64
*spte
= vcpu
->arch
.last_pte_updated
;
3122 return !!(spte
&& (*spte
& shadow_accessed_mask
));
3125 static void kvm_mmu_access_page(struct kvm_vcpu
*vcpu
, gfn_t gfn
)
3127 u64
*spte
= vcpu
->arch
.last_pte_updated
;
3130 && vcpu
->arch
.last_pte_gfn
== gfn
3131 && shadow_accessed_mask
3132 && !(*spte
& shadow_accessed_mask
)
3133 && is_shadow_present_pte(*spte
))
3134 set_bit(PT_ACCESSED_SHIFT
, (unsigned long *)spte
);
3137 void kvm_mmu_pte_write(struct kvm_vcpu
*vcpu
, gpa_t gpa
,
3138 const u8
*new, int bytes
,
3139 bool guest_initiated
)
3141 gfn_t gfn
= gpa
>> PAGE_SHIFT
;
3142 union kvm_mmu_page_role mask
= { .word
= 0 };
3143 struct kvm_mmu_page
*sp
;
3144 struct hlist_node
*node
;
3145 LIST_HEAD(invalid_list
);
3146 u64 entry
, gentry
, *spte
;
3147 unsigned pte_size
, page_offset
, misaligned
, quadrant
, offset
;
3148 int level
, npte
, invlpg_counter
, r
, flooded
= 0;
3149 bool remote_flush
, local_flush
, zap_page
;
3152 * If we don't have indirect shadow pages, it means no page is
3153 * write-protected, so we can exit simply.
3155 if (!ACCESS_ONCE(vcpu
->kvm
->arch
.indirect_shadow_pages
))
3158 zap_page
= remote_flush
= local_flush
= false;
3159 offset
= offset_in_page(gpa
);
3161 pgprintk("%s: gpa %llx bytes %d\n", __func__
, gpa
, bytes
);
3163 invlpg_counter
= atomic_read(&vcpu
->kvm
->arch
.invlpg_counter
);
3166 * Assume that the pte write on a page table of the same type
3167 * as the current vcpu paging mode since we update the sptes only
3168 * when they have the same mode.
3170 if ((is_pae(vcpu
) && bytes
== 4) || !new) {
3171 /* Handle a 32-bit guest writing two halves of a 64-bit gpte */
3176 r
= kvm_read_guest(vcpu
->kvm
, gpa
, &gentry
, min(bytes
, 8));
3179 new = (const u8
*)&gentry
;
3184 gentry
= *(const u32
*)new;
3187 gentry
= *(const u64
*)new;
3194 spin_lock(&vcpu
->kvm
->mmu_lock
);
3195 if (atomic_read(&vcpu
->kvm
->arch
.invlpg_counter
) != invlpg_counter
)
3197 kvm_mmu_free_some_pages(vcpu
);
3198 ++vcpu
->kvm
->stat
.mmu_pte_write
;
3199 trace_kvm_mmu_audit(vcpu
, AUDIT_PRE_PTE_WRITE
);
3200 if (guest_initiated
) {
3201 kvm_mmu_access_page(vcpu
, gfn
);
3202 if (gfn
== vcpu
->arch
.last_pt_write_gfn
3203 && !last_updated_pte_accessed(vcpu
)) {
3204 ++vcpu
->arch
.last_pt_write_count
;
3205 if (vcpu
->arch
.last_pt_write_count
>= 3)
3208 vcpu
->arch
.last_pt_write_gfn
= gfn
;
3209 vcpu
->arch
.last_pt_write_count
= 1;
3210 vcpu
->arch
.last_pte_updated
= NULL
;
3214 mask
.cr0_wp
= mask
.cr4_pae
= mask
.nxe
= 1;
3215 for_each_gfn_indirect_valid_sp(vcpu
->kvm
, sp
, gfn
, node
) {
3216 pte_size
= sp
->role
.cr4_pae
? 8 : 4;
3217 misaligned
= (offset
^ (offset
+ bytes
- 1)) & ~(pte_size
- 1);
3218 misaligned
|= bytes
< 4;
3219 if (misaligned
|| flooded
) {
3221 * Misaligned accesses are too much trouble to fix
3222 * up; also, they usually indicate a page is not used
3225 * If we're seeing too many writes to a page,
3226 * it may no longer be a page table, or we may be
3227 * forking, in which case it is better to unmap the
3230 pgprintk("misaligned: gpa %llx bytes %d role %x\n",
3231 gpa
, bytes
, sp
->role
.word
);
3232 zap_page
|= !!kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
,
3234 ++vcpu
->kvm
->stat
.mmu_flooded
;
3237 page_offset
= offset
;
3238 level
= sp
->role
.level
;
3240 if (!sp
->role
.cr4_pae
) {
3241 page_offset
<<= 1; /* 32->64 */
3243 * A 32-bit pde maps 4MB while the shadow pdes map
3244 * only 2MB. So we need to double the offset again
3245 * and zap two pdes instead of one.
3247 if (level
== PT32_ROOT_LEVEL
) {
3248 page_offset
&= ~7; /* kill rounding error */
3252 quadrant
= page_offset
>> PAGE_SHIFT
;
3253 page_offset
&= ~PAGE_MASK
;
3254 if (quadrant
!= sp
->role
.quadrant
)
3258 spte
= &sp
->spt
[page_offset
/ sizeof(*spte
)];
3261 mmu_page_zap_pte(vcpu
->kvm
, sp
, spte
);
3263 !((sp
->role
.word
^ vcpu
->arch
.mmu
.base_role
.word
)
3265 mmu_pte_write_new_pte(vcpu
, sp
, spte
, &gentry
);
3266 if (!remote_flush
&& need_remote_flush(entry
, *spte
))
3267 remote_flush
= true;
3271 mmu_pte_write_flush_tlb(vcpu
, zap_page
, remote_flush
, local_flush
);
3272 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
3273 trace_kvm_mmu_audit(vcpu
, AUDIT_POST_PTE_WRITE
);
3274 spin_unlock(&vcpu
->kvm
->mmu_lock
);
3277 int kvm_mmu_unprotect_page_virt(struct kvm_vcpu
*vcpu
, gva_t gva
)
3282 if (vcpu
->arch
.mmu
.direct_map
)
3285 gpa
= kvm_mmu_gva_to_gpa_read(vcpu
, gva
, NULL
);
3287 spin_lock(&vcpu
->kvm
->mmu_lock
);
3288 r
= kvm_mmu_unprotect_page(vcpu
->kvm
, gpa
>> PAGE_SHIFT
);
3289 spin_unlock(&vcpu
->kvm
->mmu_lock
);
3292 EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt
);
3294 void __kvm_mmu_free_some_pages(struct kvm_vcpu
*vcpu
)
3296 LIST_HEAD(invalid_list
);
3298 while (kvm_mmu_available_pages(vcpu
->kvm
) < KVM_REFILL_PAGES
&&
3299 !list_empty(&vcpu
->kvm
->arch
.active_mmu_pages
)) {
3300 struct kvm_mmu_page
*sp
;
3302 sp
= container_of(vcpu
->kvm
->arch
.active_mmu_pages
.prev
,
3303 struct kvm_mmu_page
, link
);
3304 kvm_mmu_prepare_zap_page(vcpu
->kvm
, sp
, &invalid_list
);
3305 kvm_mmu_commit_zap_page(vcpu
->kvm
, &invalid_list
);
3306 ++vcpu
->kvm
->stat
.mmu_recycled
;
3310 int kvm_mmu_page_fault(struct kvm_vcpu
*vcpu
, gva_t cr2
, u32 error_code
,
3311 void *insn
, int insn_len
)
3314 enum emulation_result er
;
3316 r
= vcpu
->arch
.mmu
.page_fault(vcpu
, cr2
, error_code
, false);
3325 r
= mmu_topup_memory_caches(vcpu
);
3329 er
= x86_emulate_instruction(vcpu
, cr2
, 0, insn
, insn_len
);
3334 case EMULATE_DO_MMIO
:
3335 ++vcpu
->stat
.mmio_exits
;
3345 EXPORT_SYMBOL_GPL(kvm_mmu_page_fault
);
3347 void kvm_mmu_invlpg(struct kvm_vcpu
*vcpu
, gva_t gva
)
3349 vcpu
->arch
.mmu
.invlpg(vcpu
, gva
);
3350 kvm_mmu_flush_tlb(vcpu
);
3351 ++vcpu
->stat
.invlpg
;
3353 EXPORT_SYMBOL_GPL(kvm_mmu_invlpg
);
3355 void kvm_enable_tdp(void)
3359 EXPORT_SYMBOL_GPL(kvm_enable_tdp
);
3361 void kvm_disable_tdp(void)
3363 tdp_enabled
= false;
3365 EXPORT_SYMBOL_GPL(kvm_disable_tdp
);
3367 static void free_mmu_pages(struct kvm_vcpu
*vcpu
)
3369 free_page((unsigned long)vcpu
->arch
.mmu
.pae_root
);
3370 if (vcpu
->arch
.mmu
.lm_root
!= NULL
)
3371 free_page((unsigned long)vcpu
->arch
.mmu
.lm_root
);
3374 static int alloc_mmu_pages(struct kvm_vcpu
*vcpu
)
3382 * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64.
3383 * Therefore we need to allocate shadow page tables in the first
3384 * 4GB of memory, which happens to fit the DMA32 zone.
3386 page
= alloc_page(GFP_KERNEL
| __GFP_DMA32
);
3390 vcpu
->arch
.mmu
.pae_root
= page_address(page
);
3391 for (i
= 0; i
< 4; ++i
)
3392 vcpu
->arch
.mmu
.pae_root
[i
] = INVALID_PAGE
;
3397 int kvm_mmu_create(struct kvm_vcpu
*vcpu
)
3400 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
3402 return alloc_mmu_pages(vcpu
);
3405 int kvm_mmu_setup(struct kvm_vcpu
*vcpu
)
3408 ASSERT(!VALID_PAGE(vcpu
->arch
.mmu
.root_hpa
));
3410 return init_kvm_mmu(vcpu
);
3413 void kvm_mmu_slot_remove_write_access(struct kvm
*kvm
, int slot
)
3415 struct kvm_mmu_page
*sp
;
3417 list_for_each_entry(sp
, &kvm
->arch
.active_mmu_pages
, link
) {
3421 if (!test_bit(slot
, sp
->slot_bitmap
))
3425 for (i
= 0; i
< PT64_ENT_PER_PAGE
; ++i
) {
3426 if (!is_shadow_present_pte(pt
[i
]) ||
3427 !is_last_spte(pt
[i
], sp
->role
.level
))
3430 if (is_large_pte(pt
[i
])) {
3431 drop_spte(kvm
, &pt
[i
],
3432 shadow_trap_nonpresent_pte
);
3438 if (is_writable_pte(pt
[i
]))
3439 update_spte(&pt
[i
], pt
[i
] & ~PT_WRITABLE_MASK
);
3442 kvm_flush_remote_tlbs(kvm
);
3445 void kvm_mmu_zap_all(struct kvm
*kvm
)
3447 struct kvm_mmu_page
*sp
, *node
;
3448 LIST_HEAD(invalid_list
);
3450 spin_lock(&kvm
->mmu_lock
);
3452 list_for_each_entry_safe(sp
, node
, &kvm
->arch
.active_mmu_pages
, link
)
3453 if (kvm_mmu_prepare_zap_page(kvm
, sp
, &invalid_list
))
3456 kvm_mmu_commit_zap_page(kvm
, &invalid_list
);
3457 spin_unlock(&kvm
->mmu_lock
);
3460 static int kvm_mmu_remove_some_alloc_mmu_pages(struct kvm
*kvm
,
3461 struct list_head
*invalid_list
)
3463 struct kvm_mmu_page
*page
;
3465 page
= container_of(kvm
->arch
.active_mmu_pages
.prev
,
3466 struct kvm_mmu_page
, link
);
3467 return kvm_mmu_prepare_zap_page(kvm
, page
, invalid_list
);
3470 static int mmu_shrink(struct shrinker
*shrink
, struct shrink_control
*sc
)
3473 struct kvm
*kvm_freed
= NULL
;
3474 int nr_to_scan
= sc
->nr_to_scan
;
3476 if (nr_to_scan
== 0)
3479 raw_spin_lock(&kvm_lock
);
3481 list_for_each_entry(kvm
, &vm_list
, vm_list
) {
3482 int idx
, freed_pages
;
3483 LIST_HEAD(invalid_list
);
3485 idx
= srcu_read_lock(&kvm
->srcu
);
3486 spin_lock(&kvm
->mmu_lock
);
3487 if (!kvm_freed
&& nr_to_scan
> 0 &&
3488 kvm
->arch
.n_used_mmu_pages
> 0) {
3489 freed_pages
= kvm_mmu_remove_some_alloc_mmu_pages(kvm
,
3495 kvm_mmu_commit_zap_page(kvm
, &invalid_list
);
3496 spin_unlock(&kvm
->mmu_lock
);
3497 srcu_read_unlock(&kvm
->srcu
, idx
);
3500 list_move_tail(&kvm_freed
->vm_list
, &vm_list
);
3502 raw_spin_unlock(&kvm_lock
);
3505 return percpu_counter_read_positive(&kvm_total_used_mmu_pages
);
3508 static struct shrinker mmu_shrinker
= {
3509 .shrink
= mmu_shrink
,
3510 .seeks
= DEFAULT_SEEKS
* 10,
3513 static void mmu_destroy_caches(void)
3515 if (pte_list_desc_cache
)
3516 kmem_cache_destroy(pte_list_desc_cache
);
3517 if (mmu_page_header_cache
)
3518 kmem_cache_destroy(mmu_page_header_cache
);
3521 int kvm_mmu_module_init(void)
3523 pte_list_desc_cache
= kmem_cache_create("pte_list_desc",
3524 sizeof(struct pte_list_desc
),
3526 if (!pte_list_desc_cache
)
3529 mmu_page_header_cache
= kmem_cache_create("kvm_mmu_page_header",
3530 sizeof(struct kvm_mmu_page
),
3532 if (!mmu_page_header_cache
)
3535 if (percpu_counter_init(&kvm_total_used_mmu_pages
, 0))
3538 register_shrinker(&mmu_shrinker
);
3543 mmu_destroy_caches();
3548 * Caculate mmu pages needed for kvm.
3550 unsigned int kvm_mmu_calculate_mmu_pages(struct kvm
*kvm
)
3553 unsigned int nr_mmu_pages
;
3554 unsigned int nr_pages
= 0;
3555 struct kvm_memslots
*slots
;
3557 slots
= kvm_memslots(kvm
);
3559 for (i
= 0; i
< slots
->nmemslots
; i
++)
3560 nr_pages
+= slots
->memslots
[i
].npages
;
3562 nr_mmu_pages
= nr_pages
* KVM_PERMILLE_MMU_PAGES
/ 1000;
3563 nr_mmu_pages
= max(nr_mmu_pages
,
3564 (unsigned int) KVM_MIN_ALLOC_MMU_PAGES
);
3566 return nr_mmu_pages
;
3569 static void *pv_mmu_peek_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
3572 if (len
> buffer
->len
)
3577 static void *pv_mmu_read_buffer(struct kvm_pv_mmu_op_buffer
*buffer
,
3582 ret
= pv_mmu_peek_buffer(buffer
, len
);
3587 buffer
->processed
+= len
;
3591 static int kvm_pv_mmu_write(struct kvm_vcpu
*vcpu
,
3592 gpa_t addr
, gpa_t value
)
3597 if (!is_long_mode(vcpu
) && !is_pae(vcpu
))
3600 r
= mmu_topup_memory_caches(vcpu
);
3604 if (!emulator_write_phys(vcpu
, addr
, &value
, bytes
))
3610 static int kvm_pv_mmu_flush_tlb(struct kvm_vcpu
*vcpu
)
3612 (void)kvm_set_cr3(vcpu
, kvm_read_cr3(vcpu
));
3616 static int kvm_pv_mmu_release_pt(struct kvm_vcpu
*vcpu
, gpa_t addr
)
3618 spin_lock(&vcpu
->kvm
->mmu_lock
);
3619 mmu_unshadow(vcpu
->kvm
, addr
>> PAGE_SHIFT
);
3620 spin_unlock(&vcpu
->kvm
->mmu_lock
);
3624 static int kvm_pv_mmu_op_one(struct kvm_vcpu
*vcpu
,
3625 struct kvm_pv_mmu_op_buffer
*buffer
)
3627 struct kvm_mmu_op_header
*header
;
3629 header
= pv_mmu_peek_buffer(buffer
, sizeof *header
);
3632 switch (header
->op
) {
3633 case KVM_MMU_OP_WRITE_PTE
: {
3634 struct kvm_mmu_op_write_pte
*wpte
;
3636 wpte
= pv_mmu_read_buffer(buffer
, sizeof *wpte
);
3639 return kvm_pv_mmu_write(vcpu
, wpte
->pte_phys
,
3642 case KVM_MMU_OP_FLUSH_TLB
: {
3643 struct kvm_mmu_op_flush_tlb
*ftlb
;
3645 ftlb
= pv_mmu_read_buffer(buffer
, sizeof *ftlb
);
3648 return kvm_pv_mmu_flush_tlb(vcpu
);
3650 case KVM_MMU_OP_RELEASE_PT
: {
3651 struct kvm_mmu_op_release_pt
*rpt
;
3653 rpt
= pv_mmu_read_buffer(buffer
, sizeof *rpt
);
3656 return kvm_pv_mmu_release_pt(vcpu
, rpt
->pt_phys
);
3662 int kvm_pv_mmu_op(struct kvm_vcpu
*vcpu
, unsigned long bytes
,
3663 gpa_t addr
, unsigned long *ret
)
3666 struct kvm_pv_mmu_op_buffer
*buffer
= &vcpu
->arch
.mmu_op_buffer
;
3668 buffer
->ptr
= buffer
->buf
;
3669 buffer
->len
= min_t(unsigned long, bytes
, sizeof buffer
->buf
);
3670 buffer
->processed
= 0;
3672 r
= kvm_read_guest(vcpu
->kvm
, addr
, buffer
->buf
, buffer
->len
);
3676 while (buffer
->len
) {
3677 r
= kvm_pv_mmu_op_one(vcpu
, buffer
);
3686 *ret
= buffer
->processed
;
3690 int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu
*vcpu
, u64 addr
, u64 sptes
[4])
3692 struct kvm_shadow_walk_iterator iterator
;
3695 spin_lock(&vcpu
->kvm
->mmu_lock
);
3696 for_each_shadow_entry(vcpu
, addr
, iterator
) {
3697 sptes
[iterator
.level
-1] = *iterator
.sptep
;
3699 if (!is_shadow_present_pte(*iterator
.sptep
))
3702 spin_unlock(&vcpu
->kvm
->mmu_lock
);
3706 EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy
);
3708 void kvm_mmu_destroy(struct kvm_vcpu
*vcpu
)
3712 destroy_kvm_mmu(vcpu
);
3713 free_mmu_pages(vcpu
);
3714 mmu_free_memory_caches(vcpu
);
3717 #ifdef CONFIG_KVM_MMU_AUDIT
3718 #include "mmu_audit.c"
3720 static void mmu_audit_disable(void) { }
3723 void kvm_mmu_module_exit(void)
3725 mmu_destroy_caches();
3726 percpu_counter_destroy(&kvm_total_used_mmu_pages
);
3727 unregister_shrinker(&mmu_shrinker
);
3728 mmu_audit_disable();