Commit | Line | Data |
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6aa8b732 AK |
1 | /* |
2 | * Kernel-based Virtual Machine driver for Linux | |
3 | * | |
4 | * This module enables machines with Intel VT-x extensions to run virtual | |
5 | * machines without emulation or binary translation. | |
6 | * | |
7 | * MMU support | |
8 | * | |
9 | * Copyright (C) 2006 Qumranet, Inc. | |
10 | * | |
11 | * Authors: | |
12 | * Yaniv Kamay <yaniv@qumranet.com> | |
13 | * Avi Kivity <avi@qumranet.com> | |
14 | * | |
15 | * This work is licensed under the terms of the GNU GPL, version 2. See | |
16 | * the COPYING file in the top-level directory. | |
17 | * | |
18 | */ | |
e495606d AK |
19 | |
20 | #include "vmx.h" | |
1d737c8a | 21 | #include "mmu.h" |
e495606d | 22 | |
edf88417 | 23 | #include <linux/kvm_host.h> |
6aa8b732 AK |
24 | #include <linux/types.h> |
25 | #include <linux/string.h> | |
6aa8b732 AK |
26 | #include <linux/mm.h> |
27 | #include <linux/highmem.h> | |
28 | #include <linux/module.h> | |
448353ca | 29 | #include <linux/swap.h> |
6aa8b732 | 30 | |
e495606d AK |
31 | #include <asm/page.h> |
32 | #include <asm/cmpxchg.h> | |
4e542370 | 33 | #include <asm/io.h> |
6aa8b732 | 34 | |
37a7d8b0 AK |
35 | #undef MMU_DEBUG |
36 | ||
37 | #undef AUDIT | |
38 | ||
39 | #ifdef AUDIT | |
40 | static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg); | |
41 | #else | |
42 | static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) {} | |
43 | #endif | |
44 | ||
45 | #ifdef MMU_DEBUG | |
46 | ||
47 | #define pgprintk(x...) do { if (dbg) printk(x); } while (0) | |
48 | #define rmap_printk(x...) do { if (dbg) printk(x); } while (0) | |
49 | ||
50 | #else | |
51 | ||
52 | #define pgprintk(x...) do { } while (0) | |
53 | #define rmap_printk(x...) do { } while (0) | |
54 | ||
55 | #endif | |
56 | ||
57 | #if defined(MMU_DEBUG) || defined(AUDIT) | |
58 | static int dbg = 1; | |
59 | #endif | |
6aa8b732 | 60 | |
d6c69ee9 YD |
61 | #ifndef MMU_DEBUG |
62 | #define ASSERT(x) do { } while (0) | |
63 | #else | |
6aa8b732 AK |
64 | #define ASSERT(x) \ |
65 | if (!(x)) { \ | |
66 | printk(KERN_WARNING "assertion failed %s:%d: %s\n", \ | |
67 | __FILE__, __LINE__, #x); \ | |
68 | } | |
d6c69ee9 | 69 | #endif |
6aa8b732 | 70 | |
cea0f0e7 AK |
71 | #define PT64_PT_BITS 9 |
72 | #define PT64_ENT_PER_PAGE (1 << PT64_PT_BITS) | |
73 | #define PT32_PT_BITS 10 | |
74 | #define PT32_ENT_PER_PAGE (1 << PT32_PT_BITS) | |
6aa8b732 AK |
75 | |
76 | #define PT_WRITABLE_SHIFT 1 | |
77 | ||
78 | #define PT_PRESENT_MASK (1ULL << 0) | |
79 | #define PT_WRITABLE_MASK (1ULL << PT_WRITABLE_SHIFT) | |
80 | #define PT_USER_MASK (1ULL << 2) | |
81 | #define PT_PWT_MASK (1ULL << 3) | |
82 | #define PT_PCD_MASK (1ULL << 4) | |
83 | #define PT_ACCESSED_MASK (1ULL << 5) | |
84 | #define PT_DIRTY_MASK (1ULL << 6) | |
85 | #define PT_PAGE_SIZE_MASK (1ULL << 7) | |
86 | #define PT_PAT_MASK (1ULL << 7) | |
87 | #define PT_GLOBAL_MASK (1ULL << 8) | |
fe135d2c AK |
88 | #define PT64_NX_SHIFT 63 |
89 | #define PT64_NX_MASK (1ULL << PT64_NX_SHIFT) | |
6aa8b732 AK |
90 | |
91 | #define PT_PAT_SHIFT 7 | |
92 | #define PT_DIR_PAT_SHIFT 12 | |
93 | #define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT) | |
94 | ||
95 | #define PT32_DIR_PSE36_SIZE 4 | |
96 | #define PT32_DIR_PSE36_SHIFT 13 | |
d77c26fc MD |
97 | #define PT32_DIR_PSE36_MASK \ |
98 | (((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT) | |
6aa8b732 AK |
99 | |
100 | ||
6aa8b732 AK |
101 | #define PT_FIRST_AVAIL_BITS_SHIFT 9 |
102 | #define PT64_SECOND_AVAIL_BITS_SHIFT 52 | |
103 | ||
6aa8b732 AK |
104 | #define PT_SHADOW_IO_MARK (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) |
105 | ||
6aa8b732 AK |
106 | #define VALID_PAGE(x) ((x) != INVALID_PAGE) |
107 | ||
108 | #define PT64_LEVEL_BITS 9 | |
109 | ||
110 | #define PT64_LEVEL_SHIFT(level) \ | |
d77c26fc | 111 | (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS) |
6aa8b732 AK |
112 | |
113 | #define PT64_LEVEL_MASK(level) \ | |
114 | (((1ULL << PT64_LEVEL_BITS) - 1) << PT64_LEVEL_SHIFT(level)) | |
115 | ||
116 | #define PT64_INDEX(address, level)\ | |
117 | (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1)) | |
118 | ||
119 | ||
120 | #define PT32_LEVEL_BITS 10 | |
121 | ||
122 | #define PT32_LEVEL_SHIFT(level) \ | |
d77c26fc | 123 | (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS) |
6aa8b732 AK |
124 | |
125 | #define PT32_LEVEL_MASK(level) \ | |
126 | (((1ULL << PT32_LEVEL_BITS) - 1) << PT32_LEVEL_SHIFT(level)) | |
127 | ||
128 | #define PT32_INDEX(address, level)\ | |
129 | (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1)) | |
130 | ||
131 | ||
27aba766 | 132 | #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1)) |
6aa8b732 AK |
133 | #define PT64_DIR_BASE_ADDR_MASK \ |
134 | (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1)) | |
135 | ||
136 | #define PT32_BASE_ADDR_MASK PAGE_MASK | |
137 | #define PT32_DIR_BASE_ADDR_MASK \ | |
138 | (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1)) | |
139 | ||
79539cec AK |
140 | #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ |
141 | | PT64_NX_MASK) | |
6aa8b732 AK |
142 | |
143 | #define PFERR_PRESENT_MASK (1U << 0) | |
144 | #define PFERR_WRITE_MASK (1U << 1) | |
145 | #define PFERR_USER_MASK (1U << 2) | |
73b1087e | 146 | #define PFERR_FETCH_MASK (1U << 4) |
6aa8b732 AK |
147 | |
148 | #define PT64_ROOT_LEVEL 4 | |
149 | #define PT32_ROOT_LEVEL 2 | |
150 | #define PT32E_ROOT_LEVEL 3 | |
151 | ||
152 | #define PT_DIRECTORY_LEVEL 2 | |
153 | #define PT_PAGE_TABLE_LEVEL 1 | |
154 | ||
cd4a4e53 AK |
155 | #define RMAP_EXT 4 |
156 | ||
fe135d2c AK |
157 | #define ACC_EXEC_MASK 1 |
158 | #define ACC_WRITE_MASK PT_WRITABLE_MASK | |
159 | #define ACC_USER_MASK PT_USER_MASK | |
160 | #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK) | |
161 | ||
cd4a4e53 AK |
162 | struct kvm_rmap_desc { |
163 | u64 *shadow_ptes[RMAP_EXT]; | |
164 | struct kvm_rmap_desc *more; | |
165 | }; | |
166 | ||
b5a33a75 AK |
167 | static struct kmem_cache *pte_chain_cache; |
168 | static struct kmem_cache *rmap_desc_cache; | |
d3d25b04 | 169 | static struct kmem_cache *mmu_page_header_cache; |
b5a33a75 | 170 | |
c7addb90 AK |
171 | static u64 __read_mostly shadow_trap_nonpresent_pte; |
172 | static u64 __read_mostly shadow_notrap_nonpresent_pte; | |
173 | ||
174 | void kvm_mmu_set_nonpresent_ptes(u64 trap_pte, u64 notrap_pte) | |
175 | { | |
176 | shadow_trap_nonpresent_pte = trap_pte; | |
177 | shadow_notrap_nonpresent_pte = notrap_pte; | |
178 | } | |
179 | EXPORT_SYMBOL_GPL(kvm_mmu_set_nonpresent_ptes); | |
180 | ||
6aa8b732 AK |
181 | static int is_write_protection(struct kvm_vcpu *vcpu) |
182 | { | |
ad312c7c | 183 | return vcpu->arch.cr0 & X86_CR0_WP; |
6aa8b732 AK |
184 | } |
185 | ||
186 | static int is_cpuid_PSE36(void) | |
187 | { | |
188 | return 1; | |
189 | } | |
190 | ||
73b1087e AK |
191 | static int is_nx(struct kvm_vcpu *vcpu) |
192 | { | |
ad312c7c | 193 | return vcpu->arch.shadow_efer & EFER_NX; |
73b1087e AK |
194 | } |
195 | ||
6aa8b732 AK |
196 | static int is_present_pte(unsigned long pte) |
197 | { | |
198 | return pte & PT_PRESENT_MASK; | |
199 | } | |
200 | ||
c7addb90 AK |
201 | static int is_shadow_present_pte(u64 pte) |
202 | { | |
203 | pte &= ~PT_SHADOW_IO_MARK; | |
204 | return pte != shadow_trap_nonpresent_pte | |
205 | && pte != shadow_notrap_nonpresent_pte; | |
206 | } | |
207 | ||
6aa8b732 AK |
208 | static int is_writeble_pte(unsigned long pte) |
209 | { | |
210 | return pte & PT_WRITABLE_MASK; | |
211 | } | |
212 | ||
e3c5e7ec AK |
213 | static int is_dirty_pte(unsigned long pte) |
214 | { | |
215 | return pte & PT_DIRTY_MASK; | |
216 | } | |
217 | ||
6aa8b732 AK |
218 | static int is_io_pte(unsigned long pte) |
219 | { | |
220 | return pte & PT_SHADOW_IO_MARK; | |
221 | } | |
222 | ||
cd4a4e53 AK |
223 | static int is_rmap_pte(u64 pte) |
224 | { | |
9647c14c IE |
225 | return pte != shadow_trap_nonpresent_pte |
226 | && pte != shadow_notrap_nonpresent_pte; | |
cd4a4e53 AK |
227 | } |
228 | ||
da928521 AK |
229 | static gfn_t pse36_gfn_delta(u32 gpte) |
230 | { | |
231 | int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT; | |
232 | ||
233 | return (gpte & PT32_DIR_PSE36_MASK) << shift; | |
234 | } | |
235 | ||
e663ee64 AK |
236 | static void set_shadow_pte(u64 *sptep, u64 spte) |
237 | { | |
238 | #ifdef CONFIG_X86_64 | |
239 | set_64bit((unsigned long *)sptep, spte); | |
240 | #else | |
241 | set_64bit((unsigned long long *)sptep, spte); | |
242 | #endif | |
243 | } | |
244 | ||
e2dec939 | 245 | static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, |
2e3e5882 | 246 | struct kmem_cache *base_cache, int min) |
714b93da AK |
247 | { |
248 | void *obj; | |
249 | ||
250 | if (cache->nobjs >= min) | |
e2dec939 | 251 | return 0; |
714b93da | 252 | while (cache->nobjs < ARRAY_SIZE(cache->objects)) { |
2e3e5882 | 253 | obj = kmem_cache_zalloc(base_cache, GFP_KERNEL); |
714b93da | 254 | if (!obj) |
e2dec939 | 255 | return -ENOMEM; |
714b93da AK |
256 | cache->objects[cache->nobjs++] = obj; |
257 | } | |
e2dec939 | 258 | return 0; |
714b93da AK |
259 | } |
260 | ||
261 | static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc) | |
262 | { | |
263 | while (mc->nobjs) | |
264 | kfree(mc->objects[--mc->nobjs]); | |
265 | } | |
266 | ||
c1158e63 | 267 | static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache, |
2e3e5882 | 268 | int min) |
c1158e63 AK |
269 | { |
270 | struct page *page; | |
271 | ||
272 | if (cache->nobjs >= min) | |
273 | return 0; | |
274 | while (cache->nobjs < ARRAY_SIZE(cache->objects)) { | |
2e3e5882 | 275 | page = alloc_page(GFP_KERNEL); |
c1158e63 AK |
276 | if (!page) |
277 | return -ENOMEM; | |
278 | set_page_private(page, 0); | |
279 | cache->objects[cache->nobjs++] = page_address(page); | |
280 | } | |
281 | return 0; | |
282 | } | |
283 | ||
284 | static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache *mc) | |
285 | { | |
286 | while (mc->nobjs) | |
c4d198d5 | 287 | free_page((unsigned long)mc->objects[--mc->nobjs]); |
c1158e63 AK |
288 | } |
289 | ||
2e3e5882 | 290 | static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu) |
714b93da | 291 | { |
e2dec939 AK |
292 | int r; |
293 | ||
ad312c7c | 294 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_chain_cache, |
2e3e5882 | 295 | pte_chain_cache, 4); |
e2dec939 AK |
296 | if (r) |
297 | goto out; | |
ad312c7c | 298 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache, |
2e3e5882 | 299 | rmap_desc_cache, 1); |
d3d25b04 AK |
300 | if (r) |
301 | goto out; | |
ad312c7c | 302 | r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8); |
d3d25b04 AK |
303 | if (r) |
304 | goto out; | |
ad312c7c | 305 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache, |
2e3e5882 | 306 | mmu_page_header_cache, 4); |
e2dec939 AK |
307 | out: |
308 | return r; | |
714b93da AK |
309 | } |
310 | ||
311 | static void mmu_free_memory_caches(struct kvm_vcpu *vcpu) | |
312 | { | |
ad312c7c ZX |
313 | mmu_free_memory_cache(&vcpu->arch.mmu_pte_chain_cache); |
314 | mmu_free_memory_cache(&vcpu->arch.mmu_rmap_desc_cache); | |
315 | mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache); | |
316 | mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache); | |
714b93da AK |
317 | } |
318 | ||
319 | static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc, | |
320 | size_t size) | |
321 | { | |
322 | void *p; | |
323 | ||
324 | BUG_ON(!mc->nobjs); | |
325 | p = mc->objects[--mc->nobjs]; | |
326 | memset(p, 0, size); | |
327 | return p; | |
328 | } | |
329 | ||
714b93da AK |
330 | static struct kvm_pte_chain *mmu_alloc_pte_chain(struct kvm_vcpu *vcpu) |
331 | { | |
ad312c7c | 332 | return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_chain_cache, |
714b93da AK |
333 | sizeof(struct kvm_pte_chain)); |
334 | } | |
335 | ||
90cb0529 | 336 | static void mmu_free_pte_chain(struct kvm_pte_chain *pc) |
714b93da | 337 | { |
90cb0529 | 338 | kfree(pc); |
714b93da AK |
339 | } |
340 | ||
341 | static struct kvm_rmap_desc *mmu_alloc_rmap_desc(struct kvm_vcpu *vcpu) | |
342 | { | |
ad312c7c | 343 | return mmu_memory_cache_alloc(&vcpu->arch.mmu_rmap_desc_cache, |
714b93da AK |
344 | sizeof(struct kvm_rmap_desc)); |
345 | } | |
346 | ||
90cb0529 | 347 | static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd) |
714b93da | 348 | { |
90cb0529 | 349 | kfree(rd); |
714b93da AK |
350 | } |
351 | ||
290fc38d IE |
352 | /* |
353 | * Take gfn and return the reverse mapping to it. | |
354 | * Note: gfn must be unaliased before this function get called | |
355 | */ | |
356 | ||
357 | static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn) | |
358 | { | |
359 | struct kvm_memory_slot *slot; | |
360 | ||
361 | slot = gfn_to_memslot(kvm, gfn); | |
362 | return &slot->rmap[gfn - slot->base_gfn]; | |
363 | } | |
364 | ||
cd4a4e53 AK |
365 | /* |
366 | * Reverse mapping data structures: | |
367 | * | |
290fc38d IE |
368 | * If rmapp bit zero is zero, then rmapp point to the shadw page table entry |
369 | * that points to page_address(page). | |
cd4a4e53 | 370 | * |
290fc38d IE |
371 | * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc |
372 | * containing more mappings. | |
cd4a4e53 | 373 | */ |
290fc38d | 374 | static void rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) |
cd4a4e53 | 375 | { |
4db35314 | 376 | struct kvm_mmu_page *sp; |
cd4a4e53 | 377 | struct kvm_rmap_desc *desc; |
290fc38d | 378 | unsigned long *rmapp; |
cd4a4e53 AK |
379 | int i; |
380 | ||
381 | if (!is_rmap_pte(*spte)) | |
382 | return; | |
290fc38d | 383 | gfn = unalias_gfn(vcpu->kvm, gfn); |
4db35314 AK |
384 | sp = page_header(__pa(spte)); |
385 | sp->gfns[spte - sp->spt] = gfn; | |
290fc38d IE |
386 | rmapp = gfn_to_rmap(vcpu->kvm, gfn); |
387 | if (!*rmapp) { | |
cd4a4e53 | 388 | rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte); |
290fc38d IE |
389 | *rmapp = (unsigned long)spte; |
390 | } else if (!(*rmapp & 1)) { | |
cd4a4e53 | 391 | rmap_printk("rmap_add: %p %llx 1->many\n", spte, *spte); |
714b93da | 392 | desc = mmu_alloc_rmap_desc(vcpu); |
290fc38d | 393 | desc->shadow_ptes[0] = (u64 *)*rmapp; |
cd4a4e53 | 394 | desc->shadow_ptes[1] = spte; |
290fc38d | 395 | *rmapp = (unsigned long)desc | 1; |
cd4a4e53 AK |
396 | } else { |
397 | rmap_printk("rmap_add: %p %llx many->many\n", spte, *spte); | |
290fc38d | 398 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
cd4a4e53 AK |
399 | while (desc->shadow_ptes[RMAP_EXT-1] && desc->more) |
400 | desc = desc->more; | |
401 | if (desc->shadow_ptes[RMAP_EXT-1]) { | |
714b93da | 402 | desc->more = mmu_alloc_rmap_desc(vcpu); |
cd4a4e53 AK |
403 | desc = desc->more; |
404 | } | |
405 | for (i = 0; desc->shadow_ptes[i]; ++i) | |
406 | ; | |
407 | desc->shadow_ptes[i] = spte; | |
408 | } | |
409 | } | |
410 | ||
290fc38d | 411 | static void rmap_desc_remove_entry(unsigned long *rmapp, |
cd4a4e53 AK |
412 | struct kvm_rmap_desc *desc, |
413 | int i, | |
414 | struct kvm_rmap_desc *prev_desc) | |
415 | { | |
416 | int j; | |
417 | ||
418 | for (j = RMAP_EXT - 1; !desc->shadow_ptes[j] && j > i; --j) | |
419 | ; | |
420 | desc->shadow_ptes[i] = desc->shadow_ptes[j]; | |
11718b4d | 421 | desc->shadow_ptes[j] = NULL; |
cd4a4e53 AK |
422 | if (j != 0) |
423 | return; | |
424 | if (!prev_desc && !desc->more) | |
290fc38d | 425 | *rmapp = (unsigned long)desc->shadow_ptes[0]; |
cd4a4e53 AK |
426 | else |
427 | if (prev_desc) | |
428 | prev_desc->more = desc->more; | |
429 | else | |
290fc38d | 430 | *rmapp = (unsigned long)desc->more | 1; |
90cb0529 | 431 | mmu_free_rmap_desc(desc); |
cd4a4e53 AK |
432 | } |
433 | ||
290fc38d | 434 | static void rmap_remove(struct kvm *kvm, u64 *spte) |
cd4a4e53 | 435 | { |
cd4a4e53 AK |
436 | struct kvm_rmap_desc *desc; |
437 | struct kvm_rmap_desc *prev_desc; | |
4db35314 | 438 | struct kvm_mmu_page *sp; |
76c35c6e | 439 | struct page *page; |
290fc38d | 440 | unsigned long *rmapp; |
cd4a4e53 AK |
441 | int i; |
442 | ||
443 | if (!is_rmap_pte(*spte)) | |
444 | return; | |
4db35314 | 445 | sp = page_header(__pa(spte)); |
76c35c6e | 446 | page = pfn_to_page((*spte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT); |
448353ca | 447 | mark_page_accessed(page); |
b4231d61 | 448 | if (is_writeble_pte(*spte)) |
76c35c6e | 449 | kvm_release_page_dirty(page); |
b4231d61 | 450 | else |
76c35c6e | 451 | kvm_release_page_clean(page); |
4db35314 | 452 | rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt]); |
290fc38d | 453 | if (!*rmapp) { |
cd4a4e53 AK |
454 | printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte); |
455 | BUG(); | |
290fc38d | 456 | } else if (!(*rmapp & 1)) { |
cd4a4e53 | 457 | rmap_printk("rmap_remove: %p %llx 1->0\n", spte, *spte); |
290fc38d | 458 | if ((u64 *)*rmapp != spte) { |
cd4a4e53 AK |
459 | printk(KERN_ERR "rmap_remove: %p %llx 1->BUG\n", |
460 | spte, *spte); | |
461 | BUG(); | |
462 | } | |
290fc38d | 463 | *rmapp = 0; |
cd4a4e53 AK |
464 | } else { |
465 | rmap_printk("rmap_remove: %p %llx many->many\n", spte, *spte); | |
290fc38d | 466 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
cd4a4e53 AK |
467 | prev_desc = NULL; |
468 | while (desc) { | |
469 | for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i) | |
470 | if (desc->shadow_ptes[i] == spte) { | |
290fc38d | 471 | rmap_desc_remove_entry(rmapp, |
714b93da | 472 | desc, i, |
cd4a4e53 AK |
473 | prev_desc); |
474 | return; | |
475 | } | |
476 | prev_desc = desc; | |
477 | desc = desc->more; | |
478 | } | |
479 | BUG(); | |
480 | } | |
481 | } | |
482 | ||
98348e95 | 483 | static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) |
374cbac0 | 484 | { |
374cbac0 | 485 | struct kvm_rmap_desc *desc; |
98348e95 IE |
486 | struct kvm_rmap_desc *prev_desc; |
487 | u64 *prev_spte; | |
488 | int i; | |
489 | ||
490 | if (!*rmapp) | |
491 | return NULL; | |
492 | else if (!(*rmapp & 1)) { | |
493 | if (!spte) | |
494 | return (u64 *)*rmapp; | |
495 | return NULL; | |
496 | } | |
497 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); | |
498 | prev_desc = NULL; | |
499 | prev_spte = NULL; | |
500 | while (desc) { | |
501 | for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i) { | |
502 | if (prev_spte == spte) | |
503 | return desc->shadow_ptes[i]; | |
504 | prev_spte = desc->shadow_ptes[i]; | |
505 | } | |
506 | desc = desc->more; | |
507 | } | |
508 | return NULL; | |
509 | } | |
510 | ||
511 | static void rmap_write_protect(struct kvm *kvm, u64 gfn) | |
512 | { | |
290fc38d | 513 | unsigned long *rmapp; |
374cbac0 | 514 | u64 *spte; |
caa5b8a5 | 515 | int write_protected = 0; |
374cbac0 | 516 | |
4a4c9924 AL |
517 | gfn = unalias_gfn(kvm, gfn); |
518 | rmapp = gfn_to_rmap(kvm, gfn); | |
374cbac0 | 519 | |
98348e95 IE |
520 | spte = rmap_next(kvm, rmapp, NULL); |
521 | while (spte) { | |
374cbac0 | 522 | BUG_ON(!spte); |
374cbac0 | 523 | BUG_ON(!(*spte & PT_PRESENT_MASK)); |
374cbac0 | 524 | rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); |
caa5b8a5 | 525 | if (is_writeble_pte(*spte)) { |
9647c14c | 526 | set_shadow_pte(spte, *spte & ~PT_WRITABLE_MASK); |
caa5b8a5 ED |
527 | write_protected = 1; |
528 | } | |
9647c14c | 529 | spte = rmap_next(kvm, rmapp, spte); |
374cbac0 | 530 | } |
caa5b8a5 ED |
531 | if (write_protected) |
532 | kvm_flush_remote_tlbs(kvm); | |
374cbac0 AK |
533 | } |
534 | ||
d6c69ee9 | 535 | #ifdef MMU_DEBUG |
47ad8e68 | 536 | static int is_empty_shadow_page(u64 *spt) |
6aa8b732 | 537 | { |
139bdb2d AK |
538 | u64 *pos; |
539 | u64 *end; | |
540 | ||
47ad8e68 | 541 | for (pos = spt, end = pos + PAGE_SIZE / sizeof(u64); pos != end; pos++) |
c7addb90 | 542 | if ((*pos & ~PT_SHADOW_IO_MARK) != shadow_trap_nonpresent_pte) { |
139bdb2d AK |
543 | printk(KERN_ERR "%s: %p %llx\n", __FUNCTION__, |
544 | pos, *pos); | |
6aa8b732 | 545 | return 0; |
139bdb2d | 546 | } |
6aa8b732 AK |
547 | return 1; |
548 | } | |
d6c69ee9 | 549 | #endif |
6aa8b732 | 550 | |
4db35314 | 551 | static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) |
260746c0 | 552 | { |
4db35314 AK |
553 | ASSERT(is_empty_shadow_page(sp->spt)); |
554 | list_del(&sp->link); | |
555 | __free_page(virt_to_page(sp->spt)); | |
556 | __free_page(virt_to_page(sp->gfns)); | |
557 | kfree(sp); | |
f05e70ac | 558 | ++kvm->arch.n_free_mmu_pages; |
260746c0 AK |
559 | } |
560 | ||
cea0f0e7 AK |
561 | static unsigned kvm_page_table_hashfn(gfn_t gfn) |
562 | { | |
563 | return gfn; | |
564 | } | |
565 | ||
25c0de2c AK |
566 | static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, |
567 | u64 *parent_pte) | |
6aa8b732 | 568 | { |
4db35314 | 569 | struct kvm_mmu_page *sp; |
6aa8b732 | 570 | |
ad312c7c ZX |
571 | sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache, sizeof *sp); |
572 | sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); | |
573 | sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); | |
4db35314 | 574 | set_page_private(virt_to_page(sp->spt), (unsigned long)sp); |
f05e70ac | 575 | list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); |
4db35314 AK |
576 | ASSERT(is_empty_shadow_page(sp->spt)); |
577 | sp->slot_bitmap = 0; | |
578 | sp->multimapped = 0; | |
579 | sp->parent_pte = parent_pte; | |
f05e70ac | 580 | --vcpu->kvm->arch.n_free_mmu_pages; |
4db35314 | 581 | return sp; |
6aa8b732 AK |
582 | } |
583 | ||
714b93da | 584 | static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu, |
4db35314 | 585 | struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 AK |
586 | { |
587 | struct kvm_pte_chain *pte_chain; | |
588 | struct hlist_node *node; | |
589 | int i; | |
590 | ||
591 | if (!parent_pte) | |
592 | return; | |
4db35314 AK |
593 | if (!sp->multimapped) { |
594 | u64 *old = sp->parent_pte; | |
cea0f0e7 AK |
595 | |
596 | if (!old) { | |
4db35314 | 597 | sp->parent_pte = parent_pte; |
cea0f0e7 AK |
598 | return; |
599 | } | |
4db35314 | 600 | sp->multimapped = 1; |
714b93da | 601 | pte_chain = mmu_alloc_pte_chain(vcpu); |
4db35314 AK |
602 | INIT_HLIST_HEAD(&sp->parent_ptes); |
603 | hlist_add_head(&pte_chain->link, &sp->parent_ptes); | |
cea0f0e7 AK |
604 | pte_chain->parent_ptes[0] = old; |
605 | } | |
4db35314 | 606 | hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) { |
cea0f0e7 AK |
607 | if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1]) |
608 | continue; | |
609 | for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) | |
610 | if (!pte_chain->parent_ptes[i]) { | |
611 | pte_chain->parent_ptes[i] = parent_pte; | |
612 | return; | |
613 | } | |
614 | } | |
714b93da | 615 | pte_chain = mmu_alloc_pte_chain(vcpu); |
cea0f0e7 | 616 | BUG_ON(!pte_chain); |
4db35314 | 617 | hlist_add_head(&pte_chain->link, &sp->parent_ptes); |
cea0f0e7 AK |
618 | pte_chain->parent_ptes[0] = parent_pte; |
619 | } | |
620 | ||
4db35314 | 621 | static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, |
cea0f0e7 AK |
622 | u64 *parent_pte) |
623 | { | |
624 | struct kvm_pte_chain *pte_chain; | |
625 | struct hlist_node *node; | |
626 | int i; | |
627 | ||
4db35314 AK |
628 | if (!sp->multimapped) { |
629 | BUG_ON(sp->parent_pte != parent_pte); | |
630 | sp->parent_pte = NULL; | |
cea0f0e7 AK |
631 | return; |
632 | } | |
4db35314 | 633 | hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) |
cea0f0e7 AK |
634 | for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) { |
635 | if (!pte_chain->parent_ptes[i]) | |
636 | break; | |
637 | if (pte_chain->parent_ptes[i] != parent_pte) | |
638 | continue; | |
697fe2e2 AK |
639 | while (i + 1 < NR_PTE_CHAIN_ENTRIES |
640 | && pte_chain->parent_ptes[i + 1]) { | |
cea0f0e7 AK |
641 | pte_chain->parent_ptes[i] |
642 | = pte_chain->parent_ptes[i + 1]; | |
643 | ++i; | |
644 | } | |
645 | pte_chain->parent_ptes[i] = NULL; | |
697fe2e2 AK |
646 | if (i == 0) { |
647 | hlist_del(&pte_chain->link); | |
90cb0529 | 648 | mmu_free_pte_chain(pte_chain); |
4db35314 AK |
649 | if (hlist_empty(&sp->parent_ptes)) { |
650 | sp->multimapped = 0; | |
651 | sp->parent_pte = NULL; | |
697fe2e2 AK |
652 | } |
653 | } | |
cea0f0e7 AK |
654 | return; |
655 | } | |
656 | BUG(); | |
657 | } | |
658 | ||
4db35314 | 659 | static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn) |
cea0f0e7 AK |
660 | { |
661 | unsigned index; | |
662 | struct hlist_head *bucket; | |
4db35314 | 663 | struct kvm_mmu_page *sp; |
cea0f0e7 AK |
664 | struct hlist_node *node; |
665 | ||
666 | pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn); | |
667 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 668 | bucket = &kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
669 | hlist_for_each_entry(sp, node, bucket, hash_link) |
670 | if (sp->gfn == gfn && !sp->role.metaphysical) { | |
cea0f0e7 | 671 | pgprintk("%s: found role %x\n", |
4db35314 AK |
672 | __FUNCTION__, sp->role.word); |
673 | return sp; | |
cea0f0e7 AK |
674 | } |
675 | return NULL; | |
676 | } | |
677 | ||
678 | static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, | |
679 | gfn_t gfn, | |
680 | gva_t gaddr, | |
681 | unsigned level, | |
682 | int metaphysical, | |
41074d07 | 683 | unsigned access, |
7819026e MT |
684 | u64 *parent_pte, |
685 | bool *new_page) | |
cea0f0e7 AK |
686 | { |
687 | union kvm_mmu_page_role role; | |
688 | unsigned index; | |
689 | unsigned quadrant; | |
690 | struct hlist_head *bucket; | |
4db35314 | 691 | struct kvm_mmu_page *sp; |
cea0f0e7 AK |
692 | struct hlist_node *node; |
693 | ||
694 | role.word = 0; | |
ad312c7c | 695 | role.glevels = vcpu->arch.mmu.root_level; |
cea0f0e7 AK |
696 | role.level = level; |
697 | role.metaphysical = metaphysical; | |
41074d07 | 698 | role.access = access; |
ad312c7c | 699 | if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) { |
cea0f0e7 AK |
700 | quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); |
701 | quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1; | |
702 | role.quadrant = quadrant; | |
703 | } | |
704 | pgprintk("%s: looking gfn %lx role %x\n", __FUNCTION__, | |
705 | gfn, role.word); | |
706 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 707 | bucket = &vcpu->kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
708 | hlist_for_each_entry(sp, node, bucket, hash_link) |
709 | if (sp->gfn == gfn && sp->role.word == role.word) { | |
710 | mmu_page_add_parent_pte(vcpu, sp, parent_pte); | |
cea0f0e7 | 711 | pgprintk("%s: found\n", __FUNCTION__); |
4db35314 | 712 | return sp; |
cea0f0e7 | 713 | } |
dfc5aa00 | 714 | ++vcpu->kvm->stat.mmu_cache_miss; |
4db35314 AK |
715 | sp = kvm_mmu_alloc_page(vcpu, parent_pte); |
716 | if (!sp) | |
717 | return sp; | |
cea0f0e7 | 718 | pgprintk("%s: adding gfn %lx role %x\n", __FUNCTION__, gfn, role.word); |
4db35314 AK |
719 | sp->gfn = gfn; |
720 | sp->role = role; | |
721 | hlist_add_head(&sp->hash_link, bucket); | |
ad312c7c | 722 | vcpu->arch.mmu.prefetch_page(vcpu, sp); |
374cbac0 | 723 | if (!metaphysical) |
4a4c9924 | 724 | rmap_write_protect(vcpu->kvm, gfn); |
7819026e MT |
725 | if (new_page) |
726 | *new_page = 1; | |
4db35314 | 727 | return sp; |
cea0f0e7 AK |
728 | } |
729 | ||
90cb0529 | 730 | static void kvm_mmu_page_unlink_children(struct kvm *kvm, |
4db35314 | 731 | struct kvm_mmu_page *sp) |
a436036b | 732 | { |
697fe2e2 AK |
733 | unsigned i; |
734 | u64 *pt; | |
735 | u64 ent; | |
736 | ||
4db35314 | 737 | pt = sp->spt; |
697fe2e2 | 738 | |
4db35314 | 739 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) { |
697fe2e2 | 740 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { |
c7addb90 | 741 | if (is_shadow_present_pte(pt[i])) |
290fc38d | 742 | rmap_remove(kvm, &pt[i]); |
c7addb90 | 743 | pt[i] = shadow_trap_nonpresent_pte; |
697fe2e2 | 744 | } |
90cb0529 | 745 | kvm_flush_remote_tlbs(kvm); |
697fe2e2 AK |
746 | return; |
747 | } | |
748 | ||
749 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { | |
750 | ent = pt[i]; | |
751 | ||
c7addb90 AK |
752 | pt[i] = shadow_trap_nonpresent_pte; |
753 | if (!is_shadow_present_pte(ent)) | |
697fe2e2 AK |
754 | continue; |
755 | ent &= PT64_BASE_ADDR_MASK; | |
90cb0529 | 756 | mmu_page_remove_parent_pte(page_header(ent), &pt[i]); |
697fe2e2 | 757 | } |
90cb0529 | 758 | kvm_flush_remote_tlbs(kvm); |
a436036b AK |
759 | } |
760 | ||
4db35314 | 761 | static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 | 762 | { |
4db35314 | 763 | mmu_page_remove_parent_pte(sp, parent_pte); |
a436036b AK |
764 | } |
765 | ||
12b7d28f AK |
766 | static void kvm_mmu_reset_last_pte_updated(struct kvm *kvm) |
767 | { | |
768 | int i; | |
769 | ||
770 | for (i = 0; i < KVM_MAX_VCPUS; ++i) | |
771 | if (kvm->vcpus[i]) | |
ad312c7c | 772 | kvm->vcpus[i]->arch.last_pte_updated = NULL; |
12b7d28f AK |
773 | } |
774 | ||
4db35314 | 775 | static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp) |
a436036b AK |
776 | { |
777 | u64 *parent_pte; | |
778 | ||
4cee5764 | 779 | ++kvm->stat.mmu_shadow_zapped; |
4db35314 AK |
780 | while (sp->multimapped || sp->parent_pte) { |
781 | if (!sp->multimapped) | |
782 | parent_pte = sp->parent_pte; | |
a436036b AK |
783 | else { |
784 | struct kvm_pte_chain *chain; | |
785 | ||
4db35314 | 786 | chain = container_of(sp->parent_ptes.first, |
a436036b AK |
787 | struct kvm_pte_chain, link); |
788 | parent_pte = chain->parent_ptes[0]; | |
789 | } | |
697fe2e2 | 790 | BUG_ON(!parent_pte); |
4db35314 | 791 | kvm_mmu_put_page(sp, parent_pte); |
c7addb90 | 792 | set_shadow_pte(parent_pte, shadow_trap_nonpresent_pte); |
a436036b | 793 | } |
4db35314 AK |
794 | kvm_mmu_page_unlink_children(kvm, sp); |
795 | if (!sp->root_count) { | |
796 | hlist_del(&sp->hash_link); | |
797 | kvm_mmu_free_page(kvm, sp); | |
36868f7b | 798 | } else |
f05e70ac | 799 | list_move(&sp->link, &kvm->arch.active_mmu_pages); |
12b7d28f | 800 | kvm_mmu_reset_last_pte_updated(kvm); |
a436036b AK |
801 | } |
802 | ||
82ce2c96 IE |
803 | /* |
804 | * Changing the number of mmu pages allocated to the vm | |
805 | * Note: if kvm_nr_mmu_pages is too small, you will get dead lock | |
806 | */ | |
807 | void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) | |
808 | { | |
809 | /* | |
810 | * If we set the number of mmu pages to be smaller be than the | |
811 | * number of actived pages , we must to free some mmu pages before we | |
812 | * change the value | |
813 | */ | |
814 | ||
f05e70ac | 815 | if ((kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages) > |
82ce2c96 | 816 | kvm_nr_mmu_pages) { |
f05e70ac ZX |
817 | int n_used_mmu_pages = kvm->arch.n_alloc_mmu_pages |
818 | - kvm->arch.n_free_mmu_pages; | |
82ce2c96 IE |
819 | |
820 | while (n_used_mmu_pages > kvm_nr_mmu_pages) { | |
821 | struct kvm_mmu_page *page; | |
822 | ||
f05e70ac | 823 | page = container_of(kvm->arch.active_mmu_pages.prev, |
82ce2c96 IE |
824 | struct kvm_mmu_page, link); |
825 | kvm_mmu_zap_page(kvm, page); | |
826 | n_used_mmu_pages--; | |
827 | } | |
f05e70ac | 828 | kvm->arch.n_free_mmu_pages = 0; |
82ce2c96 IE |
829 | } |
830 | else | |
f05e70ac ZX |
831 | kvm->arch.n_free_mmu_pages += kvm_nr_mmu_pages |
832 | - kvm->arch.n_alloc_mmu_pages; | |
82ce2c96 | 833 | |
f05e70ac | 834 | kvm->arch.n_alloc_mmu_pages = kvm_nr_mmu_pages; |
82ce2c96 IE |
835 | } |
836 | ||
f67a46f4 | 837 | static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) |
a436036b AK |
838 | { |
839 | unsigned index; | |
840 | struct hlist_head *bucket; | |
4db35314 | 841 | struct kvm_mmu_page *sp; |
a436036b AK |
842 | struct hlist_node *node, *n; |
843 | int r; | |
844 | ||
845 | pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn); | |
846 | r = 0; | |
847 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 848 | bucket = &kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
849 | hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) |
850 | if (sp->gfn == gfn && !sp->role.metaphysical) { | |
697fe2e2 | 851 | pgprintk("%s: gfn %lx role %x\n", __FUNCTION__, gfn, |
4db35314 AK |
852 | sp->role.word); |
853 | kvm_mmu_zap_page(kvm, sp); | |
a436036b AK |
854 | r = 1; |
855 | } | |
856 | return r; | |
cea0f0e7 AK |
857 | } |
858 | ||
f67a46f4 | 859 | static void mmu_unshadow(struct kvm *kvm, gfn_t gfn) |
97a0a01e | 860 | { |
4db35314 | 861 | struct kvm_mmu_page *sp; |
97a0a01e | 862 | |
4db35314 AK |
863 | while ((sp = kvm_mmu_lookup_page(kvm, gfn)) != NULL) { |
864 | pgprintk("%s: zap %lx %x\n", __FUNCTION__, gfn, sp->role.word); | |
865 | kvm_mmu_zap_page(kvm, sp); | |
97a0a01e AK |
866 | } |
867 | } | |
868 | ||
38c335f1 | 869 | static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn) |
6aa8b732 | 870 | { |
38c335f1 | 871 | int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn)); |
4db35314 | 872 | struct kvm_mmu_page *sp = page_header(__pa(pte)); |
6aa8b732 | 873 | |
4db35314 | 874 | __set_bit(slot, &sp->slot_bitmap); |
6aa8b732 AK |
875 | } |
876 | ||
039576c0 AK |
877 | struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva) |
878 | { | |
ad312c7c | 879 | gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); |
039576c0 AK |
880 | |
881 | if (gpa == UNMAPPED_GVA) | |
882 | return NULL; | |
1d28f5f4 | 883 | return gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); |
039576c0 AK |
884 | } |
885 | ||
1c4f1fd6 AK |
886 | static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte, |
887 | unsigned pt_access, unsigned pte_access, | |
888 | int user_fault, int write_fault, int dirty, | |
d7824fff | 889 | int *ptwrite, gfn_t gfn, struct page *page) |
1c4f1fd6 AK |
890 | { |
891 | u64 spte; | |
892 | int was_rmapped = is_rmap_pte(*shadow_pte); | |
75e68e60 | 893 | int was_writeble = is_writeble_pte(*shadow_pte); |
1c4f1fd6 | 894 | |
bc750ba8 | 895 | pgprintk("%s: spte %llx access %x write_fault %d" |
1c4f1fd6 | 896 | " user_fault %d gfn %lx\n", |
bc750ba8 | 897 | __FUNCTION__, *shadow_pte, pt_access, |
1c4f1fd6 AK |
898 | write_fault, user_fault, gfn); |
899 | ||
900 | /* | |
901 | * We don't set the accessed bit, since we sometimes want to see | |
902 | * whether the guest actually used the pte (in order to detect | |
903 | * demand paging). | |
904 | */ | |
905 | spte = PT_PRESENT_MASK | PT_DIRTY_MASK; | |
906 | if (!dirty) | |
907 | pte_access &= ~ACC_WRITE_MASK; | |
908 | if (!(pte_access & ACC_EXEC_MASK)) | |
909 | spte |= PT64_NX_MASK; | |
910 | ||
1c4f1fd6 AK |
911 | spte |= PT_PRESENT_MASK; |
912 | if (pte_access & ACC_USER_MASK) | |
913 | spte |= PT_USER_MASK; | |
914 | ||
915 | if (is_error_page(page)) { | |
916 | set_shadow_pte(shadow_pte, | |
917 | shadow_trap_nonpresent_pte | PT_SHADOW_IO_MARK); | |
918 | kvm_release_page_clean(page); | |
919 | return; | |
920 | } | |
921 | ||
922 | spte |= page_to_phys(page); | |
923 | ||
924 | if ((pte_access & ACC_WRITE_MASK) | |
925 | || (write_fault && !is_write_protection(vcpu) && !user_fault)) { | |
926 | struct kvm_mmu_page *shadow; | |
927 | ||
928 | spte |= PT_WRITABLE_MASK; | |
929 | if (user_fault) { | |
930 | mmu_unshadow(vcpu->kvm, gfn); | |
931 | goto unshadowed; | |
932 | } | |
933 | ||
934 | shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn); | |
935 | if (shadow) { | |
936 | pgprintk("%s: found shadow page for %lx, marking ro\n", | |
937 | __FUNCTION__, gfn); | |
938 | pte_access &= ~ACC_WRITE_MASK; | |
939 | if (is_writeble_pte(spte)) { | |
940 | spte &= ~PT_WRITABLE_MASK; | |
941 | kvm_x86_ops->tlb_flush(vcpu); | |
942 | } | |
943 | if (write_fault) | |
944 | *ptwrite = 1; | |
945 | } | |
946 | } | |
947 | ||
948 | unshadowed: | |
949 | ||
950 | if (pte_access & ACC_WRITE_MASK) | |
951 | mark_page_dirty(vcpu->kvm, gfn); | |
952 | ||
953 | pgprintk("%s: setting spte %llx\n", __FUNCTION__, spte); | |
954 | set_shadow_pte(shadow_pte, spte); | |
955 | page_header_update_slot(vcpu->kvm, shadow_pte, gfn); | |
956 | if (!was_rmapped) { | |
957 | rmap_add(vcpu, shadow_pte, gfn); | |
958 | if (!is_rmap_pte(*shadow_pte)) | |
959 | kvm_release_page_clean(page); | |
75e68e60 IE |
960 | } else { |
961 | if (was_writeble) | |
962 | kvm_release_page_dirty(page); | |
963 | else | |
964 | kvm_release_page_clean(page); | |
1c4f1fd6 | 965 | } |
1c4f1fd6 | 966 | if (!ptwrite || !*ptwrite) |
ad312c7c | 967 | vcpu->arch.last_pte_updated = shadow_pte; |
1c4f1fd6 AK |
968 | } |
969 | ||
6aa8b732 AK |
970 | static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) |
971 | { | |
972 | } | |
973 | ||
aaee2c94 MT |
974 | static int __nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, |
975 | gfn_t gfn, struct page *page) | |
6aa8b732 AK |
976 | { |
977 | int level = PT32E_ROOT_LEVEL; | |
ad312c7c | 978 | hpa_t table_addr = vcpu->arch.mmu.root_hpa; |
e833240f | 979 | int pt_write = 0; |
6aa8b732 AK |
980 | |
981 | for (; ; level--) { | |
982 | u32 index = PT64_INDEX(v, level); | |
983 | u64 *table; | |
984 | ||
985 | ASSERT(VALID_PAGE(table_addr)); | |
986 | table = __va(table_addr); | |
987 | ||
988 | if (level == 1) { | |
e833240f | 989 | mmu_set_spte(vcpu, &table[index], ACC_ALL, ACC_ALL, |
d7824fff | 990 | 0, write, 1, &pt_write, gfn, page); |
e833240f | 991 | return pt_write || is_io_pte(table[index]); |
6aa8b732 AK |
992 | } |
993 | ||
c7addb90 | 994 | if (table[index] == shadow_trap_nonpresent_pte) { |
25c0de2c | 995 | struct kvm_mmu_page *new_table; |
cea0f0e7 | 996 | gfn_t pseudo_gfn; |
6aa8b732 | 997 | |
cea0f0e7 AK |
998 | pseudo_gfn = (v & PT64_DIR_BASE_ADDR_MASK) |
999 | >> PAGE_SHIFT; | |
1000 | new_table = kvm_mmu_get_page(vcpu, pseudo_gfn, | |
1001 | v, level - 1, | |
7819026e MT |
1002 | 1, ACC_ALL, &table[index], |
1003 | NULL); | |
25c0de2c | 1004 | if (!new_table) { |
6aa8b732 | 1005 | pgprintk("nonpaging_map: ENOMEM\n"); |
d7824fff | 1006 | kvm_release_page_clean(page); |
6aa8b732 AK |
1007 | return -ENOMEM; |
1008 | } | |
1009 | ||
47ad8e68 | 1010 | table[index] = __pa(new_table->spt) | PT_PRESENT_MASK |
25c0de2c | 1011 | | PT_WRITABLE_MASK | PT_USER_MASK; |
6aa8b732 AK |
1012 | } |
1013 | table_addr = table[index] & PT64_BASE_ADDR_MASK; | |
1014 | } | |
1015 | } | |
1016 | ||
10589a46 MT |
1017 | static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) |
1018 | { | |
1019 | int r; | |
1020 | ||
aaee2c94 MT |
1021 | struct page *page; |
1022 | ||
1023 | down_read(¤t->mm->mmap_sem); | |
1024 | page = gfn_to_page(vcpu->kvm, gfn); | |
1025 | ||
1026 | spin_lock(&vcpu->kvm->mmu_lock); | |
eb787d10 | 1027 | kvm_mmu_free_some_pages(vcpu); |
aaee2c94 MT |
1028 | r = __nonpaging_map(vcpu, v, write, gfn, page); |
1029 | spin_unlock(&vcpu->kvm->mmu_lock); | |
1030 | ||
1031 | up_read(¤t->mm->mmap_sem); | |
1032 | ||
10589a46 MT |
1033 | return r; |
1034 | } | |
1035 | ||
1036 | ||
c7addb90 AK |
1037 | static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu, |
1038 | struct kvm_mmu_page *sp) | |
1039 | { | |
1040 | int i; | |
1041 | ||
1042 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) | |
1043 | sp->spt[i] = shadow_trap_nonpresent_pte; | |
1044 | } | |
1045 | ||
17ac10ad AK |
1046 | static void mmu_free_roots(struct kvm_vcpu *vcpu) |
1047 | { | |
1048 | int i; | |
4db35314 | 1049 | struct kvm_mmu_page *sp; |
17ac10ad | 1050 | |
ad312c7c | 1051 | if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) |
7b53aa56 | 1052 | return; |
aaee2c94 | 1053 | spin_lock(&vcpu->kvm->mmu_lock); |
17ac10ad | 1054 | #ifdef CONFIG_X86_64 |
ad312c7c ZX |
1055 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { |
1056 | hpa_t root = vcpu->arch.mmu.root_hpa; | |
17ac10ad | 1057 | |
4db35314 AK |
1058 | sp = page_header(root); |
1059 | --sp->root_count; | |
ad312c7c | 1060 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
aaee2c94 | 1061 | spin_unlock(&vcpu->kvm->mmu_lock); |
17ac10ad AK |
1062 | return; |
1063 | } | |
1064 | #endif | |
1065 | for (i = 0; i < 4; ++i) { | |
ad312c7c | 1066 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad | 1067 | |
417726a3 | 1068 | if (root) { |
417726a3 | 1069 | root &= PT64_BASE_ADDR_MASK; |
4db35314 AK |
1070 | sp = page_header(root); |
1071 | --sp->root_count; | |
417726a3 | 1072 | } |
ad312c7c | 1073 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 1074 | } |
aaee2c94 | 1075 | spin_unlock(&vcpu->kvm->mmu_lock); |
ad312c7c | 1076 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
17ac10ad AK |
1077 | } |
1078 | ||
1079 | static void mmu_alloc_roots(struct kvm_vcpu *vcpu) | |
1080 | { | |
1081 | int i; | |
cea0f0e7 | 1082 | gfn_t root_gfn; |
4db35314 | 1083 | struct kvm_mmu_page *sp; |
3bb65a22 | 1084 | |
ad312c7c | 1085 | root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT; |
17ac10ad AK |
1086 | |
1087 | #ifdef CONFIG_X86_64 | |
ad312c7c ZX |
1088 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { |
1089 | hpa_t root = vcpu->arch.mmu.root_hpa; | |
17ac10ad AK |
1090 | |
1091 | ASSERT(!VALID_PAGE(root)); | |
4db35314 | 1092 | sp = kvm_mmu_get_page(vcpu, root_gfn, 0, |
7819026e | 1093 | PT64_ROOT_LEVEL, 0, ACC_ALL, NULL, NULL); |
4db35314 AK |
1094 | root = __pa(sp->spt); |
1095 | ++sp->root_count; | |
ad312c7c | 1096 | vcpu->arch.mmu.root_hpa = root; |
17ac10ad AK |
1097 | return; |
1098 | } | |
1099 | #endif | |
1100 | for (i = 0; i < 4; ++i) { | |
ad312c7c | 1101 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad AK |
1102 | |
1103 | ASSERT(!VALID_PAGE(root)); | |
ad312c7c ZX |
1104 | if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) { |
1105 | if (!is_present_pte(vcpu->arch.pdptrs[i])) { | |
1106 | vcpu->arch.mmu.pae_root[i] = 0; | |
417726a3 AK |
1107 | continue; |
1108 | } | |
ad312c7c ZX |
1109 | root_gfn = vcpu->arch.pdptrs[i] >> PAGE_SHIFT; |
1110 | } else if (vcpu->arch.mmu.root_level == 0) | |
cea0f0e7 | 1111 | root_gfn = 0; |
4db35314 AK |
1112 | sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, |
1113 | PT32_ROOT_LEVEL, !is_paging(vcpu), | |
7819026e | 1114 | ACC_ALL, NULL, NULL); |
4db35314 AK |
1115 | root = __pa(sp->spt); |
1116 | ++sp->root_count; | |
ad312c7c | 1117 | vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; |
17ac10ad | 1118 | } |
ad312c7c | 1119 | vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); |
17ac10ad AK |
1120 | } |
1121 | ||
6aa8b732 AK |
1122 | static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr) |
1123 | { | |
1124 | return vaddr; | |
1125 | } | |
1126 | ||
1127 | static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, | |
3f3e7124 | 1128 | u32 error_code) |
6aa8b732 | 1129 | { |
e833240f | 1130 | gfn_t gfn; |
e2dec939 | 1131 | int r; |
6aa8b732 | 1132 | |
e833240f | 1133 | pgprintk("%s: gva %lx error %x\n", __FUNCTION__, gva, error_code); |
e2dec939 AK |
1134 | r = mmu_topup_memory_caches(vcpu); |
1135 | if (r) | |
1136 | return r; | |
714b93da | 1137 | |
6aa8b732 | 1138 | ASSERT(vcpu); |
ad312c7c | 1139 | ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 | 1140 | |
e833240f | 1141 | gfn = gva >> PAGE_SHIFT; |
6aa8b732 | 1142 | |
e833240f AK |
1143 | return nonpaging_map(vcpu, gva & PAGE_MASK, |
1144 | error_code & PFERR_WRITE_MASK, gfn); | |
6aa8b732 AK |
1145 | } |
1146 | ||
6aa8b732 AK |
1147 | static void nonpaging_free(struct kvm_vcpu *vcpu) |
1148 | { | |
17ac10ad | 1149 | mmu_free_roots(vcpu); |
6aa8b732 AK |
1150 | } |
1151 | ||
1152 | static int nonpaging_init_context(struct kvm_vcpu *vcpu) | |
1153 | { | |
ad312c7c | 1154 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1155 | |
1156 | context->new_cr3 = nonpaging_new_cr3; | |
1157 | context->page_fault = nonpaging_page_fault; | |
6aa8b732 AK |
1158 | context->gva_to_gpa = nonpaging_gva_to_gpa; |
1159 | context->free = nonpaging_free; | |
c7addb90 | 1160 | context->prefetch_page = nonpaging_prefetch_page; |
cea0f0e7 | 1161 | context->root_level = 0; |
6aa8b732 | 1162 | context->shadow_root_level = PT32E_ROOT_LEVEL; |
17c3ba9d | 1163 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1164 | return 0; |
1165 | } | |
1166 | ||
d835dfec | 1167 | void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu) |
6aa8b732 | 1168 | { |
1165f5fe | 1169 | ++vcpu->stat.tlb_flush; |
cbdd1bea | 1170 | kvm_x86_ops->tlb_flush(vcpu); |
6aa8b732 AK |
1171 | } |
1172 | ||
1173 | static void paging_new_cr3(struct kvm_vcpu *vcpu) | |
1174 | { | |
374cbac0 | 1175 | pgprintk("%s: cr3 %lx\n", __FUNCTION__, vcpu->cr3); |
cea0f0e7 | 1176 | mmu_free_roots(vcpu); |
6aa8b732 AK |
1177 | } |
1178 | ||
6aa8b732 AK |
1179 | static void inject_page_fault(struct kvm_vcpu *vcpu, |
1180 | u64 addr, | |
1181 | u32 err_code) | |
1182 | { | |
c3c91fee | 1183 | kvm_inject_page_fault(vcpu, addr, err_code); |
6aa8b732 AK |
1184 | } |
1185 | ||
6aa8b732 AK |
1186 | static void paging_free(struct kvm_vcpu *vcpu) |
1187 | { | |
1188 | nonpaging_free(vcpu); | |
1189 | } | |
1190 | ||
1191 | #define PTTYPE 64 | |
1192 | #include "paging_tmpl.h" | |
1193 | #undef PTTYPE | |
1194 | ||
1195 | #define PTTYPE 32 | |
1196 | #include "paging_tmpl.h" | |
1197 | #undef PTTYPE | |
1198 | ||
17ac10ad | 1199 | static int paging64_init_context_common(struct kvm_vcpu *vcpu, int level) |
6aa8b732 | 1200 | { |
ad312c7c | 1201 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1202 | |
1203 | ASSERT(is_pae(vcpu)); | |
1204 | context->new_cr3 = paging_new_cr3; | |
1205 | context->page_fault = paging64_page_fault; | |
6aa8b732 | 1206 | context->gva_to_gpa = paging64_gva_to_gpa; |
c7addb90 | 1207 | context->prefetch_page = paging64_prefetch_page; |
6aa8b732 | 1208 | context->free = paging_free; |
17ac10ad AK |
1209 | context->root_level = level; |
1210 | context->shadow_root_level = level; | |
17c3ba9d | 1211 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1212 | return 0; |
1213 | } | |
1214 | ||
17ac10ad AK |
1215 | static int paging64_init_context(struct kvm_vcpu *vcpu) |
1216 | { | |
1217 | return paging64_init_context_common(vcpu, PT64_ROOT_LEVEL); | |
1218 | } | |
1219 | ||
6aa8b732 AK |
1220 | static int paging32_init_context(struct kvm_vcpu *vcpu) |
1221 | { | |
ad312c7c | 1222 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1223 | |
1224 | context->new_cr3 = paging_new_cr3; | |
1225 | context->page_fault = paging32_page_fault; | |
6aa8b732 AK |
1226 | context->gva_to_gpa = paging32_gva_to_gpa; |
1227 | context->free = paging_free; | |
c7addb90 | 1228 | context->prefetch_page = paging32_prefetch_page; |
6aa8b732 AK |
1229 | context->root_level = PT32_ROOT_LEVEL; |
1230 | context->shadow_root_level = PT32E_ROOT_LEVEL; | |
17c3ba9d | 1231 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1232 | return 0; |
1233 | } | |
1234 | ||
1235 | static int paging32E_init_context(struct kvm_vcpu *vcpu) | |
1236 | { | |
17ac10ad | 1237 | return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL); |
6aa8b732 AK |
1238 | } |
1239 | ||
1240 | static int init_kvm_mmu(struct kvm_vcpu *vcpu) | |
1241 | { | |
1242 | ASSERT(vcpu); | |
ad312c7c | 1243 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 AK |
1244 | |
1245 | if (!is_paging(vcpu)) | |
1246 | return nonpaging_init_context(vcpu); | |
a9058ecd | 1247 | else if (is_long_mode(vcpu)) |
6aa8b732 AK |
1248 | return paging64_init_context(vcpu); |
1249 | else if (is_pae(vcpu)) | |
1250 | return paging32E_init_context(vcpu); | |
1251 | else | |
1252 | return paging32_init_context(vcpu); | |
1253 | } | |
1254 | ||
1255 | static void destroy_kvm_mmu(struct kvm_vcpu *vcpu) | |
1256 | { | |
1257 | ASSERT(vcpu); | |
ad312c7c ZX |
1258 | if (VALID_PAGE(vcpu->arch.mmu.root_hpa)) { |
1259 | vcpu->arch.mmu.free(vcpu); | |
1260 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; | |
6aa8b732 AK |
1261 | } |
1262 | } | |
1263 | ||
1264 | int kvm_mmu_reset_context(struct kvm_vcpu *vcpu) | |
17c3ba9d AK |
1265 | { |
1266 | destroy_kvm_mmu(vcpu); | |
1267 | return init_kvm_mmu(vcpu); | |
1268 | } | |
8668a3c4 | 1269 | EXPORT_SYMBOL_GPL(kvm_mmu_reset_context); |
17c3ba9d AK |
1270 | |
1271 | int kvm_mmu_load(struct kvm_vcpu *vcpu) | |
6aa8b732 | 1272 | { |
714b93da AK |
1273 | int r; |
1274 | ||
e2dec939 | 1275 | r = mmu_topup_memory_caches(vcpu); |
17c3ba9d AK |
1276 | if (r) |
1277 | goto out; | |
aaee2c94 | 1278 | spin_lock(&vcpu->kvm->mmu_lock); |
eb787d10 | 1279 | kvm_mmu_free_some_pages(vcpu); |
17c3ba9d | 1280 | mmu_alloc_roots(vcpu); |
aaee2c94 | 1281 | spin_unlock(&vcpu->kvm->mmu_lock); |
ad312c7c | 1282 | kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa); |
17c3ba9d | 1283 | kvm_mmu_flush_tlb(vcpu); |
714b93da AK |
1284 | out: |
1285 | return r; | |
6aa8b732 | 1286 | } |
17c3ba9d AK |
1287 | EXPORT_SYMBOL_GPL(kvm_mmu_load); |
1288 | ||
1289 | void kvm_mmu_unload(struct kvm_vcpu *vcpu) | |
1290 | { | |
1291 | mmu_free_roots(vcpu); | |
1292 | } | |
6aa8b732 | 1293 | |
09072daf | 1294 | static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu, |
4db35314 | 1295 | struct kvm_mmu_page *sp, |
ac1b714e AK |
1296 | u64 *spte) |
1297 | { | |
1298 | u64 pte; | |
1299 | struct kvm_mmu_page *child; | |
1300 | ||
1301 | pte = *spte; | |
c7addb90 | 1302 | if (is_shadow_present_pte(pte)) { |
4db35314 | 1303 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) |
290fc38d | 1304 | rmap_remove(vcpu->kvm, spte); |
ac1b714e AK |
1305 | else { |
1306 | child = page_header(pte & PT64_BASE_ADDR_MASK); | |
90cb0529 | 1307 | mmu_page_remove_parent_pte(child, spte); |
ac1b714e AK |
1308 | } |
1309 | } | |
c7addb90 | 1310 | set_shadow_pte(spte, shadow_trap_nonpresent_pte); |
ac1b714e AK |
1311 | } |
1312 | ||
0028425f | 1313 | static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, |
4db35314 | 1314 | struct kvm_mmu_page *sp, |
0028425f | 1315 | u64 *spte, |
c7addb90 AK |
1316 | const void *new, int bytes, |
1317 | int offset_in_pte) | |
0028425f | 1318 | { |
4db35314 | 1319 | if (sp->role.level != PT_PAGE_TABLE_LEVEL) { |
4cee5764 | 1320 | ++vcpu->kvm->stat.mmu_pde_zapped; |
0028425f | 1321 | return; |
4cee5764 | 1322 | } |
0028425f | 1323 | |
4cee5764 | 1324 | ++vcpu->kvm->stat.mmu_pte_updated; |
4db35314 AK |
1325 | if (sp->role.glevels == PT32_ROOT_LEVEL) |
1326 | paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); | |
0028425f | 1327 | else |
4db35314 | 1328 | paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); |
0028425f AK |
1329 | } |
1330 | ||
79539cec AK |
1331 | static bool need_remote_flush(u64 old, u64 new) |
1332 | { | |
1333 | if (!is_shadow_present_pte(old)) | |
1334 | return false; | |
1335 | if (!is_shadow_present_pte(new)) | |
1336 | return true; | |
1337 | if ((old ^ new) & PT64_BASE_ADDR_MASK) | |
1338 | return true; | |
1339 | old ^= PT64_NX_MASK; | |
1340 | new ^= PT64_NX_MASK; | |
1341 | return (old & ~new & PT64_PERM_MASK) != 0; | |
1342 | } | |
1343 | ||
1344 | static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, u64 old, u64 new) | |
1345 | { | |
1346 | if (need_remote_flush(old, new)) | |
1347 | kvm_flush_remote_tlbs(vcpu->kvm); | |
1348 | else | |
1349 | kvm_mmu_flush_tlb(vcpu); | |
1350 | } | |
1351 | ||
12b7d28f AK |
1352 | static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) |
1353 | { | |
ad312c7c | 1354 | u64 *spte = vcpu->arch.last_pte_updated; |
12b7d28f AK |
1355 | |
1356 | return !!(spte && (*spte & PT_ACCESSED_MASK)); | |
1357 | } | |
1358 | ||
d7824fff AK |
1359 | static void mmu_guess_page_from_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, |
1360 | const u8 *new, int bytes) | |
1361 | { | |
1362 | gfn_t gfn; | |
1363 | int r; | |
1364 | u64 gpte = 0; | |
1365 | ||
1366 | if (bytes != 4 && bytes != 8) | |
1367 | return; | |
1368 | ||
1369 | /* | |
1370 | * Assume that the pte write on a page table of the same type | |
1371 | * as the current vcpu paging mode. This is nearly always true | |
1372 | * (might be false while changing modes). Note it is verified later | |
1373 | * by update_pte(). | |
1374 | */ | |
1375 | if (is_pae(vcpu)) { | |
1376 | /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ | |
1377 | if ((bytes == 4) && (gpa % 4 == 0)) { | |
1378 | r = kvm_read_guest(vcpu->kvm, gpa & ~(u64)7, &gpte, 8); | |
1379 | if (r) | |
1380 | return; | |
1381 | memcpy((void *)&gpte + (gpa % 8), new, 4); | |
1382 | } else if ((bytes == 8) && (gpa % 8 == 0)) { | |
1383 | memcpy((void *)&gpte, new, 8); | |
1384 | } | |
1385 | } else { | |
1386 | if ((bytes == 4) && (gpa % 4 == 0)) | |
1387 | memcpy((void *)&gpte, new, 4); | |
1388 | } | |
1389 | if (!is_present_pte(gpte)) | |
1390 | return; | |
1391 | gfn = (gpte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; | |
1392 | vcpu->arch.update_pte.gfn = gfn; | |
1393 | vcpu->arch.update_pte.page = gfn_to_page(vcpu->kvm, gfn); | |
1394 | } | |
1395 | ||
09072daf | 1396 | void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, |
fe551881 | 1397 | const u8 *new, int bytes) |
da4a00f0 | 1398 | { |
9b7a0325 | 1399 | gfn_t gfn = gpa >> PAGE_SHIFT; |
4db35314 | 1400 | struct kvm_mmu_page *sp; |
0e7bc4b9 | 1401 | struct hlist_node *node, *n; |
9b7a0325 AK |
1402 | struct hlist_head *bucket; |
1403 | unsigned index; | |
79539cec | 1404 | u64 entry; |
9b7a0325 | 1405 | u64 *spte; |
9b7a0325 | 1406 | unsigned offset = offset_in_page(gpa); |
0e7bc4b9 | 1407 | unsigned pte_size; |
9b7a0325 | 1408 | unsigned page_offset; |
0e7bc4b9 | 1409 | unsigned misaligned; |
fce0657f | 1410 | unsigned quadrant; |
9b7a0325 | 1411 | int level; |
86a5ba02 | 1412 | int flooded = 0; |
ac1b714e | 1413 | int npte; |
9b7a0325 | 1414 | |
da4a00f0 | 1415 | pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes); |
d7824fff | 1416 | mmu_guess_page_from_pte_write(vcpu, gpa, new, bytes); |
aaee2c94 | 1417 | spin_lock(&vcpu->kvm->mmu_lock); |
eb787d10 | 1418 | kvm_mmu_free_some_pages(vcpu); |
4cee5764 | 1419 | ++vcpu->kvm->stat.mmu_pte_write; |
c7addb90 | 1420 | kvm_mmu_audit(vcpu, "pre pte write"); |
ad312c7c | 1421 | if (gfn == vcpu->arch.last_pt_write_gfn |
12b7d28f | 1422 | && !last_updated_pte_accessed(vcpu)) { |
ad312c7c ZX |
1423 | ++vcpu->arch.last_pt_write_count; |
1424 | if (vcpu->arch.last_pt_write_count >= 3) | |
86a5ba02 AK |
1425 | flooded = 1; |
1426 | } else { | |
ad312c7c ZX |
1427 | vcpu->arch.last_pt_write_gfn = gfn; |
1428 | vcpu->arch.last_pt_write_count = 1; | |
1429 | vcpu->arch.last_pte_updated = NULL; | |
86a5ba02 | 1430 | } |
9b7a0325 | 1431 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; |
f05e70ac | 1432 | bucket = &vcpu->kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
1433 | hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) { |
1434 | if (sp->gfn != gfn || sp->role.metaphysical) | |
9b7a0325 | 1435 | continue; |
4db35314 | 1436 | pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8; |
0e7bc4b9 | 1437 | misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); |
e925c5ba | 1438 | misaligned |= bytes < 4; |
86a5ba02 | 1439 | if (misaligned || flooded) { |
0e7bc4b9 AK |
1440 | /* |
1441 | * Misaligned accesses are too much trouble to fix | |
1442 | * up; also, they usually indicate a page is not used | |
1443 | * as a page table. | |
86a5ba02 AK |
1444 | * |
1445 | * If we're seeing too many writes to a page, | |
1446 | * it may no longer be a page table, or we may be | |
1447 | * forking, in which case it is better to unmap the | |
1448 | * page. | |
0e7bc4b9 AK |
1449 | */ |
1450 | pgprintk("misaligned: gpa %llx bytes %d role %x\n", | |
4db35314 AK |
1451 | gpa, bytes, sp->role.word); |
1452 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
4cee5764 | 1453 | ++vcpu->kvm->stat.mmu_flooded; |
0e7bc4b9 AK |
1454 | continue; |
1455 | } | |
9b7a0325 | 1456 | page_offset = offset; |
4db35314 | 1457 | level = sp->role.level; |
ac1b714e | 1458 | npte = 1; |
4db35314 | 1459 | if (sp->role.glevels == PT32_ROOT_LEVEL) { |
ac1b714e AK |
1460 | page_offset <<= 1; /* 32->64 */ |
1461 | /* | |
1462 | * A 32-bit pde maps 4MB while the shadow pdes map | |
1463 | * only 2MB. So we need to double the offset again | |
1464 | * and zap two pdes instead of one. | |
1465 | */ | |
1466 | if (level == PT32_ROOT_LEVEL) { | |
6b8d0f9b | 1467 | page_offset &= ~7; /* kill rounding error */ |
ac1b714e AK |
1468 | page_offset <<= 1; |
1469 | npte = 2; | |
1470 | } | |
fce0657f | 1471 | quadrant = page_offset >> PAGE_SHIFT; |
9b7a0325 | 1472 | page_offset &= ~PAGE_MASK; |
4db35314 | 1473 | if (quadrant != sp->role.quadrant) |
fce0657f | 1474 | continue; |
9b7a0325 | 1475 | } |
4db35314 | 1476 | spte = &sp->spt[page_offset / sizeof(*spte)]; |
ac1b714e | 1477 | while (npte--) { |
79539cec | 1478 | entry = *spte; |
4db35314 AK |
1479 | mmu_pte_write_zap_pte(vcpu, sp, spte); |
1480 | mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes, | |
c7addb90 | 1481 | page_offset & (pte_size - 1)); |
79539cec | 1482 | mmu_pte_write_flush_tlb(vcpu, entry, *spte); |
ac1b714e | 1483 | ++spte; |
9b7a0325 | 1484 | } |
9b7a0325 | 1485 | } |
c7addb90 | 1486 | kvm_mmu_audit(vcpu, "post pte write"); |
aaee2c94 | 1487 | spin_unlock(&vcpu->kvm->mmu_lock); |
d7824fff AK |
1488 | if (vcpu->arch.update_pte.page) { |
1489 | kvm_release_page_clean(vcpu->arch.update_pte.page); | |
1490 | vcpu->arch.update_pte.page = NULL; | |
1491 | } | |
da4a00f0 AK |
1492 | } |
1493 | ||
a436036b AK |
1494 | int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) |
1495 | { | |
10589a46 MT |
1496 | gpa_t gpa; |
1497 | int r; | |
a436036b | 1498 | |
10589a46 MT |
1499 | down_read(¤t->mm->mmap_sem); |
1500 | gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); | |
1501 | up_read(¤t->mm->mmap_sem); | |
1502 | ||
aaee2c94 | 1503 | spin_lock(&vcpu->kvm->mmu_lock); |
10589a46 | 1504 | r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT); |
aaee2c94 | 1505 | spin_unlock(&vcpu->kvm->mmu_lock); |
10589a46 | 1506 | return r; |
a436036b AK |
1507 | } |
1508 | ||
22d95b12 | 1509 | void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) |
ebeace86 | 1510 | { |
f05e70ac | 1511 | while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) { |
4db35314 | 1512 | struct kvm_mmu_page *sp; |
ebeace86 | 1513 | |
f05e70ac | 1514 | sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev, |
4db35314 AK |
1515 | struct kvm_mmu_page, link); |
1516 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
4cee5764 | 1517 | ++vcpu->kvm->stat.mmu_recycled; |
ebeace86 AK |
1518 | } |
1519 | } | |
ebeace86 | 1520 | |
3067714c AK |
1521 | int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code) |
1522 | { | |
1523 | int r; | |
1524 | enum emulation_result er; | |
1525 | ||
ad312c7c | 1526 | r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code); |
3067714c AK |
1527 | if (r < 0) |
1528 | goto out; | |
1529 | ||
1530 | if (!r) { | |
1531 | r = 1; | |
1532 | goto out; | |
1533 | } | |
1534 | ||
b733bfb5 AK |
1535 | r = mmu_topup_memory_caches(vcpu); |
1536 | if (r) | |
1537 | goto out; | |
1538 | ||
3067714c | 1539 | er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0); |
3067714c AK |
1540 | |
1541 | switch (er) { | |
1542 | case EMULATE_DONE: | |
1543 | return 1; | |
1544 | case EMULATE_DO_MMIO: | |
1545 | ++vcpu->stat.mmio_exits; | |
1546 | return 0; | |
1547 | case EMULATE_FAIL: | |
1548 | kvm_report_emulation_failure(vcpu, "pagetable"); | |
1549 | return 1; | |
1550 | default: | |
1551 | BUG(); | |
1552 | } | |
1553 | out: | |
3067714c AK |
1554 | return r; |
1555 | } | |
1556 | EXPORT_SYMBOL_GPL(kvm_mmu_page_fault); | |
1557 | ||
6aa8b732 AK |
1558 | static void free_mmu_pages(struct kvm_vcpu *vcpu) |
1559 | { | |
4db35314 | 1560 | struct kvm_mmu_page *sp; |
6aa8b732 | 1561 | |
f05e70ac ZX |
1562 | while (!list_empty(&vcpu->kvm->arch.active_mmu_pages)) { |
1563 | sp = container_of(vcpu->kvm->arch.active_mmu_pages.next, | |
4db35314 AK |
1564 | struct kvm_mmu_page, link); |
1565 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
f51234c2 | 1566 | } |
ad312c7c | 1567 | free_page((unsigned long)vcpu->arch.mmu.pae_root); |
6aa8b732 AK |
1568 | } |
1569 | ||
1570 | static int alloc_mmu_pages(struct kvm_vcpu *vcpu) | |
1571 | { | |
17ac10ad | 1572 | struct page *page; |
6aa8b732 AK |
1573 | int i; |
1574 | ||
1575 | ASSERT(vcpu); | |
1576 | ||
f05e70ac ZX |
1577 | if (vcpu->kvm->arch.n_requested_mmu_pages) |
1578 | vcpu->kvm->arch.n_free_mmu_pages = | |
1579 | vcpu->kvm->arch.n_requested_mmu_pages; | |
82ce2c96 | 1580 | else |
f05e70ac ZX |
1581 | vcpu->kvm->arch.n_free_mmu_pages = |
1582 | vcpu->kvm->arch.n_alloc_mmu_pages; | |
17ac10ad AK |
1583 | /* |
1584 | * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. | |
1585 | * Therefore we need to allocate shadow page tables in the first | |
1586 | * 4GB of memory, which happens to fit the DMA32 zone. | |
1587 | */ | |
1588 | page = alloc_page(GFP_KERNEL | __GFP_DMA32); | |
1589 | if (!page) | |
1590 | goto error_1; | |
ad312c7c | 1591 | vcpu->arch.mmu.pae_root = page_address(page); |
17ac10ad | 1592 | for (i = 0; i < 4; ++i) |
ad312c7c | 1593 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 1594 | |
6aa8b732 AK |
1595 | return 0; |
1596 | ||
1597 | error_1: | |
1598 | free_mmu_pages(vcpu); | |
1599 | return -ENOMEM; | |
1600 | } | |
1601 | ||
8018c27b | 1602 | int kvm_mmu_create(struct kvm_vcpu *vcpu) |
6aa8b732 | 1603 | { |
6aa8b732 | 1604 | ASSERT(vcpu); |
ad312c7c | 1605 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 | 1606 | |
8018c27b IM |
1607 | return alloc_mmu_pages(vcpu); |
1608 | } | |
6aa8b732 | 1609 | |
8018c27b IM |
1610 | int kvm_mmu_setup(struct kvm_vcpu *vcpu) |
1611 | { | |
1612 | ASSERT(vcpu); | |
ad312c7c | 1613 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
2c264957 | 1614 | |
8018c27b | 1615 | return init_kvm_mmu(vcpu); |
6aa8b732 AK |
1616 | } |
1617 | ||
1618 | void kvm_mmu_destroy(struct kvm_vcpu *vcpu) | |
1619 | { | |
1620 | ASSERT(vcpu); | |
1621 | ||
1622 | destroy_kvm_mmu(vcpu); | |
1623 | free_mmu_pages(vcpu); | |
714b93da | 1624 | mmu_free_memory_caches(vcpu); |
6aa8b732 AK |
1625 | } |
1626 | ||
90cb0529 | 1627 | void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) |
6aa8b732 | 1628 | { |
4db35314 | 1629 | struct kvm_mmu_page *sp; |
6aa8b732 | 1630 | |
f05e70ac | 1631 | list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) { |
6aa8b732 AK |
1632 | int i; |
1633 | u64 *pt; | |
1634 | ||
4db35314 | 1635 | if (!test_bit(slot, &sp->slot_bitmap)) |
6aa8b732 AK |
1636 | continue; |
1637 | ||
4db35314 | 1638 | pt = sp->spt; |
6aa8b732 AK |
1639 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) |
1640 | /* avoid RMW */ | |
9647c14c | 1641 | if (pt[i] & PT_WRITABLE_MASK) |
6aa8b732 | 1642 | pt[i] &= ~PT_WRITABLE_MASK; |
6aa8b732 AK |
1643 | } |
1644 | } | |
37a7d8b0 | 1645 | |
90cb0529 | 1646 | void kvm_mmu_zap_all(struct kvm *kvm) |
e0fa826f | 1647 | { |
4db35314 | 1648 | struct kvm_mmu_page *sp, *node; |
e0fa826f | 1649 | |
aaee2c94 | 1650 | spin_lock(&kvm->mmu_lock); |
f05e70ac | 1651 | list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) |
4db35314 | 1652 | kvm_mmu_zap_page(kvm, sp); |
aaee2c94 | 1653 | spin_unlock(&kvm->mmu_lock); |
e0fa826f | 1654 | |
90cb0529 | 1655 | kvm_flush_remote_tlbs(kvm); |
e0fa826f DL |
1656 | } |
1657 | ||
b5a33a75 AK |
1658 | void kvm_mmu_module_exit(void) |
1659 | { | |
1660 | if (pte_chain_cache) | |
1661 | kmem_cache_destroy(pte_chain_cache); | |
1662 | if (rmap_desc_cache) | |
1663 | kmem_cache_destroy(rmap_desc_cache); | |
d3d25b04 AK |
1664 | if (mmu_page_header_cache) |
1665 | kmem_cache_destroy(mmu_page_header_cache); | |
b5a33a75 AK |
1666 | } |
1667 | ||
1668 | int kvm_mmu_module_init(void) | |
1669 | { | |
1670 | pte_chain_cache = kmem_cache_create("kvm_pte_chain", | |
1671 | sizeof(struct kvm_pte_chain), | |
20c2df83 | 1672 | 0, 0, NULL); |
b5a33a75 AK |
1673 | if (!pte_chain_cache) |
1674 | goto nomem; | |
1675 | rmap_desc_cache = kmem_cache_create("kvm_rmap_desc", | |
1676 | sizeof(struct kvm_rmap_desc), | |
20c2df83 | 1677 | 0, 0, NULL); |
b5a33a75 AK |
1678 | if (!rmap_desc_cache) |
1679 | goto nomem; | |
1680 | ||
d3d25b04 AK |
1681 | mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header", |
1682 | sizeof(struct kvm_mmu_page), | |
20c2df83 | 1683 | 0, 0, NULL); |
d3d25b04 AK |
1684 | if (!mmu_page_header_cache) |
1685 | goto nomem; | |
1686 | ||
b5a33a75 AK |
1687 | return 0; |
1688 | ||
1689 | nomem: | |
1690 | kvm_mmu_module_exit(); | |
1691 | return -ENOMEM; | |
1692 | } | |
1693 | ||
3ad82a7e ZX |
1694 | /* |
1695 | * Caculate mmu pages needed for kvm. | |
1696 | */ | |
1697 | unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) | |
1698 | { | |
1699 | int i; | |
1700 | unsigned int nr_mmu_pages; | |
1701 | unsigned int nr_pages = 0; | |
1702 | ||
1703 | for (i = 0; i < kvm->nmemslots; i++) | |
1704 | nr_pages += kvm->memslots[i].npages; | |
1705 | ||
1706 | nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; | |
1707 | nr_mmu_pages = max(nr_mmu_pages, | |
1708 | (unsigned int) KVM_MIN_ALLOC_MMU_PAGES); | |
1709 | ||
1710 | return nr_mmu_pages; | |
1711 | } | |
1712 | ||
37a7d8b0 AK |
1713 | #ifdef AUDIT |
1714 | ||
1715 | static const char *audit_msg; | |
1716 | ||
1717 | static gva_t canonicalize(gva_t gva) | |
1718 | { | |
1719 | #ifdef CONFIG_X86_64 | |
1720 | gva = (long long)(gva << 16) >> 16; | |
1721 | #endif | |
1722 | return gva; | |
1723 | } | |
1724 | ||
1725 | static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, | |
1726 | gva_t va, int level) | |
1727 | { | |
1728 | u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); | |
1729 | int i; | |
1730 | gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); | |
1731 | ||
1732 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { | |
1733 | u64 ent = pt[i]; | |
1734 | ||
c7addb90 | 1735 | if (ent == shadow_trap_nonpresent_pte) |
37a7d8b0 AK |
1736 | continue; |
1737 | ||
1738 | va = canonicalize(va); | |
c7addb90 AK |
1739 | if (level > 1) { |
1740 | if (ent == shadow_notrap_nonpresent_pte) | |
1741 | printk(KERN_ERR "audit: (%s) nontrapping pte" | |
1742 | " in nonleaf level: levels %d gva %lx" | |
1743 | " level %d pte %llx\n", audit_msg, | |
ad312c7c | 1744 | vcpu->arch.mmu.root_level, va, level, ent); |
c7addb90 | 1745 | |
37a7d8b0 | 1746 | audit_mappings_page(vcpu, ent, va, level - 1); |
c7addb90 | 1747 | } else { |
ad312c7c | 1748 | gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va); |
1d28f5f4 AK |
1749 | struct page *page = gpa_to_page(vcpu, gpa); |
1750 | hpa_t hpa = page_to_phys(page); | |
37a7d8b0 | 1751 | |
c7addb90 | 1752 | if (is_shadow_present_pte(ent) |
37a7d8b0 | 1753 | && (ent & PT64_BASE_ADDR_MASK) != hpa) |
c7addb90 AK |
1754 | printk(KERN_ERR "xx audit error: (%s) levels %d" |
1755 | " gva %lx gpa %llx hpa %llx ent %llx %d\n", | |
ad312c7c | 1756 | audit_msg, vcpu->arch.mmu.root_level, |
d77c26fc MD |
1757 | va, gpa, hpa, ent, |
1758 | is_shadow_present_pte(ent)); | |
c7addb90 AK |
1759 | else if (ent == shadow_notrap_nonpresent_pte |
1760 | && !is_error_hpa(hpa)) | |
1761 | printk(KERN_ERR "audit: (%s) notrap shadow," | |
1762 | " valid guest gva %lx\n", audit_msg, va); | |
b4231d61 | 1763 | kvm_release_page_clean(page); |
c7addb90 | 1764 | |
37a7d8b0 AK |
1765 | } |
1766 | } | |
1767 | } | |
1768 | ||
1769 | static void audit_mappings(struct kvm_vcpu *vcpu) | |
1770 | { | |
1ea252af | 1771 | unsigned i; |
37a7d8b0 | 1772 | |
ad312c7c ZX |
1773 | if (vcpu->arch.mmu.root_level == 4) |
1774 | audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); | |
37a7d8b0 AK |
1775 | else |
1776 | for (i = 0; i < 4; ++i) | |
ad312c7c | 1777 | if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) |
37a7d8b0 | 1778 | audit_mappings_page(vcpu, |
ad312c7c | 1779 | vcpu->arch.mmu.pae_root[i], |
37a7d8b0 AK |
1780 | i << 30, |
1781 | 2); | |
1782 | } | |
1783 | ||
1784 | static int count_rmaps(struct kvm_vcpu *vcpu) | |
1785 | { | |
1786 | int nmaps = 0; | |
1787 | int i, j, k; | |
1788 | ||
1789 | for (i = 0; i < KVM_MEMORY_SLOTS; ++i) { | |
1790 | struct kvm_memory_slot *m = &vcpu->kvm->memslots[i]; | |
1791 | struct kvm_rmap_desc *d; | |
1792 | ||
1793 | for (j = 0; j < m->npages; ++j) { | |
290fc38d | 1794 | unsigned long *rmapp = &m->rmap[j]; |
37a7d8b0 | 1795 | |
290fc38d | 1796 | if (!*rmapp) |
37a7d8b0 | 1797 | continue; |
290fc38d | 1798 | if (!(*rmapp & 1)) { |
37a7d8b0 AK |
1799 | ++nmaps; |
1800 | continue; | |
1801 | } | |
290fc38d | 1802 | d = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
37a7d8b0 AK |
1803 | while (d) { |
1804 | for (k = 0; k < RMAP_EXT; ++k) | |
1805 | if (d->shadow_ptes[k]) | |
1806 | ++nmaps; | |
1807 | else | |
1808 | break; | |
1809 | d = d->more; | |
1810 | } | |
1811 | } | |
1812 | } | |
1813 | return nmaps; | |
1814 | } | |
1815 | ||
1816 | static int count_writable_mappings(struct kvm_vcpu *vcpu) | |
1817 | { | |
1818 | int nmaps = 0; | |
4db35314 | 1819 | struct kvm_mmu_page *sp; |
37a7d8b0 AK |
1820 | int i; |
1821 | ||
f05e70ac | 1822 | list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { |
4db35314 | 1823 | u64 *pt = sp->spt; |
37a7d8b0 | 1824 | |
4db35314 | 1825 | if (sp->role.level != PT_PAGE_TABLE_LEVEL) |
37a7d8b0 AK |
1826 | continue; |
1827 | ||
1828 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { | |
1829 | u64 ent = pt[i]; | |
1830 | ||
1831 | if (!(ent & PT_PRESENT_MASK)) | |
1832 | continue; | |
1833 | if (!(ent & PT_WRITABLE_MASK)) | |
1834 | continue; | |
1835 | ++nmaps; | |
1836 | } | |
1837 | } | |
1838 | return nmaps; | |
1839 | } | |
1840 | ||
1841 | static void audit_rmap(struct kvm_vcpu *vcpu) | |
1842 | { | |
1843 | int n_rmap = count_rmaps(vcpu); | |
1844 | int n_actual = count_writable_mappings(vcpu); | |
1845 | ||
1846 | if (n_rmap != n_actual) | |
1847 | printk(KERN_ERR "%s: (%s) rmap %d actual %d\n", | |
1848 | __FUNCTION__, audit_msg, n_rmap, n_actual); | |
1849 | } | |
1850 | ||
1851 | static void audit_write_protection(struct kvm_vcpu *vcpu) | |
1852 | { | |
4db35314 | 1853 | struct kvm_mmu_page *sp; |
290fc38d IE |
1854 | struct kvm_memory_slot *slot; |
1855 | unsigned long *rmapp; | |
1856 | gfn_t gfn; | |
37a7d8b0 | 1857 | |
f05e70ac | 1858 | list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { |
4db35314 | 1859 | if (sp->role.metaphysical) |
37a7d8b0 AK |
1860 | continue; |
1861 | ||
4db35314 AK |
1862 | slot = gfn_to_memslot(vcpu->kvm, sp->gfn); |
1863 | gfn = unalias_gfn(vcpu->kvm, sp->gfn); | |
290fc38d IE |
1864 | rmapp = &slot->rmap[gfn - slot->base_gfn]; |
1865 | if (*rmapp) | |
37a7d8b0 AK |
1866 | printk(KERN_ERR "%s: (%s) shadow page has writable" |
1867 | " mappings: gfn %lx role %x\n", | |
4db35314 AK |
1868 | __FUNCTION__, audit_msg, sp->gfn, |
1869 | sp->role.word); | |
37a7d8b0 AK |
1870 | } |
1871 | } | |
1872 | ||
1873 | static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) | |
1874 | { | |
1875 | int olddbg = dbg; | |
1876 | ||
1877 | dbg = 0; | |
1878 | audit_msg = msg; | |
1879 | audit_rmap(vcpu); | |
1880 | audit_write_protection(vcpu); | |
1881 | audit_mappings(vcpu); | |
1882 | dbg = olddbg; | |
1883 | } | |
1884 | ||
1885 | #endif |