]>
Commit | Line | Data |
---|---|---|
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 | ||
2e3e5882 | 294 | kvm_mmu_free_some_pages(vcpu); |
ad312c7c | 295 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_chain_cache, |
2e3e5882 | 296 | pte_chain_cache, 4); |
e2dec939 AK |
297 | if (r) |
298 | goto out; | |
ad312c7c | 299 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_rmap_desc_cache, |
2e3e5882 | 300 | rmap_desc_cache, 1); |
d3d25b04 AK |
301 | if (r) |
302 | goto out; | |
ad312c7c | 303 | r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8); |
d3d25b04 AK |
304 | if (r) |
305 | goto out; | |
ad312c7c | 306 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache, |
2e3e5882 | 307 | mmu_page_header_cache, 4); |
e2dec939 AK |
308 | out: |
309 | return r; | |
714b93da AK |
310 | } |
311 | ||
312 | static void mmu_free_memory_caches(struct kvm_vcpu *vcpu) | |
313 | { | |
ad312c7c ZX |
314 | mmu_free_memory_cache(&vcpu->arch.mmu_pte_chain_cache); |
315 | mmu_free_memory_cache(&vcpu->arch.mmu_rmap_desc_cache); | |
316 | mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache); | |
317 | mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache); | |
714b93da AK |
318 | } |
319 | ||
320 | static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc, | |
321 | size_t size) | |
322 | { | |
323 | void *p; | |
324 | ||
325 | BUG_ON(!mc->nobjs); | |
326 | p = mc->objects[--mc->nobjs]; | |
327 | memset(p, 0, size); | |
328 | return p; | |
329 | } | |
330 | ||
714b93da AK |
331 | static struct kvm_pte_chain *mmu_alloc_pte_chain(struct kvm_vcpu *vcpu) |
332 | { | |
ad312c7c | 333 | return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_chain_cache, |
714b93da AK |
334 | sizeof(struct kvm_pte_chain)); |
335 | } | |
336 | ||
90cb0529 | 337 | static void mmu_free_pte_chain(struct kvm_pte_chain *pc) |
714b93da | 338 | { |
90cb0529 | 339 | kfree(pc); |
714b93da AK |
340 | } |
341 | ||
342 | static struct kvm_rmap_desc *mmu_alloc_rmap_desc(struct kvm_vcpu *vcpu) | |
343 | { | |
ad312c7c | 344 | return mmu_memory_cache_alloc(&vcpu->arch.mmu_rmap_desc_cache, |
714b93da AK |
345 | sizeof(struct kvm_rmap_desc)); |
346 | } | |
347 | ||
90cb0529 | 348 | static void mmu_free_rmap_desc(struct kvm_rmap_desc *rd) |
714b93da | 349 | { |
90cb0529 | 350 | kfree(rd); |
714b93da AK |
351 | } |
352 | ||
290fc38d IE |
353 | /* |
354 | * Take gfn and return the reverse mapping to it. | |
355 | * Note: gfn must be unaliased before this function get called | |
356 | */ | |
357 | ||
358 | static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn) | |
359 | { | |
360 | struct kvm_memory_slot *slot; | |
361 | ||
362 | slot = gfn_to_memslot(kvm, gfn); | |
363 | return &slot->rmap[gfn - slot->base_gfn]; | |
364 | } | |
365 | ||
cd4a4e53 AK |
366 | /* |
367 | * Reverse mapping data structures: | |
368 | * | |
290fc38d IE |
369 | * If rmapp bit zero is zero, then rmapp point to the shadw page table entry |
370 | * that points to page_address(page). | |
cd4a4e53 | 371 | * |
290fc38d IE |
372 | * If rmapp bit zero is one, (then rmap & ~1) points to a struct kvm_rmap_desc |
373 | * containing more mappings. | |
cd4a4e53 | 374 | */ |
290fc38d | 375 | static void rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) |
cd4a4e53 | 376 | { |
4db35314 | 377 | struct kvm_mmu_page *sp; |
cd4a4e53 | 378 | struct kvm_rmap_desc *desc; |
290fc38d | 379 | unsigned long *rmapp; |
cd4a4e53 AK |
380 | int i; |
381 | ||
382 | if (!is_rmap_pte(*spte)) | |
383 | return; | |
290fc38d | 384 | gfn = unalias_gfn(vcpu->kvm, gfn); |
4db35314 AK |
385 | sp = page_header(__pa(spte)); |
386 | sp->gfns[spte - sp->spt] = gfn; | |
290fc38d IE |
387 | rmapp = gfn_to_rmap(vcpu->kvm, gfn); |
388 | if (!*rmapp) { | |
cd4a4e53 | 389 | rmap_printk("rmap_add: %p %llx 0->1\n", spte, *spte); |
290fc38d IE |
390 | *rmapp = (unsigned long)spte; |
391 | } else if (!(*rmapp & 1)) { | |
cd4a4e53 | 392 | rmap_printk("rmap_add: %p %llx 1->many\n", spte, *spte); |
714b93da | 393 | desc = mmu_alloc_rmap_desc(vcpu); |
290fc38d | 394 | desc->shadow_ptes[0] = (u64 *)*rmapp; |
cd4a4e53 | 395 | desc->shadow_ptes[1] = spte; |
290fc38d | 396 | *rmapp = (unsigned long)desc | 1; |
cd4a4e53 AK |
397 | } else { |
398 | rmap_printk("rmap_add: %p %llx many->many\n", spte, *spte); | |
290fc38d | 399 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
cd4a4e53 AK |
400 | while (desc->shadow_ptes[RMAP_EXT-1] && desc->more) |
401 | desc = desc->more; | |
402 | if (desc->shadow_ptes[RMAP_EXT-1]) { | |
714b93da | 403 | desc->more = mmu_alloc_rmap_desc(vcpu); |
cd4a4e53 AK |
404 | desc = desc->more; |
405 | } | |
406 | for (i = 0; desc->shadow_ptes[i]; ++i) | |
407 | ; | |
408 | desc->shadow_ptes[i] = spte; | |
409 | } | |
410 | } | |
411 | ||
290fc38d | 412 | static void rmap_desc_remove_entry(unsigned long *rmapp, |
cd4a4e53 AK |
413 | struct kvm_rmap_desc *desc, |
414 | int i, | |
415 | struct kvm_rmap_desc *prev_desc) | |
416 | { | |
417 | int j; | |
418 | ||
419 | for (j = RMAP_EXT - 1; !desc->shadow_ptes[j] && j > i; --j) | |
420 | ; | |
421 | desc->shadow_ptes[i] = desc->shadow_ptes[j]; | |
11718b4d | 422 | desc->shadow_ptes[j] = NULL; |
cd4a4e53 AK |
423 | if (j != 0) |
424 | return; | |
425 | if (!prev_desc && !desc->more) | |
290fc38d | 426 | *rmapp = (unsigned long)desc->shadow_ptes[0]; |
cd4a4e53 AK |
427 | else |
428 | if (prev_desc) | |
429 | prev_desc->more = desc->more; | |
430 | else | |
290fc38d | 431 | *rmapp = (unsigned long)desc->more | 1; |
90cb0529 | 432 | mmu_free_rmap_desc(desc); |
cd4a4e53 AK |
433 | } |
434 | ||
290fc38d | 435 | static void rmap_remove(struct kvm *kvm, u64 *spte) |
cd4a4e53 | 436 | { |
cd4a4e53 AK |
437 | struct kvm_rmap_desc *desc; |
438 | struct kvm_rmap_desc *prev_desc; | |
4db35314 | 439 | struct kvm_mmu_page *sp; |
76c35c6e | 440 | struct page *page; |
290fc38d | 441 | unsigned long *rmapp; |
cd4a4e53 AK |
442 | int i; |
443 | ||
444 | if (!is_rmap_pte(*spte)) | |
445 | return; | |
4db35314 | 446 | sp = page_header(__pa(spte)); |
76c35c6e | 447 | page = pfn_to_page((*spte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT); |
448353ca | 448 | mark_page_accessed(page); |
b4231d61 | 449 | if (is_writeble_pte(*spte)) |
76c35c6e | 450 | kvm_release_page_dirty(page); |
b4231d61 | 451 | else |
76c35c6e | 452 | kvm_release_page_clean(page); |
4db35314 | 453 | rmapp = gfn_to_rmap(kvm, sp->gfns[spte - sp->spt]); |
290fc38d | 454 | if (!*rmapp) { |
cd4a4e53 AK |
455 | printk(KERN_ERR "rmap_remove: %p %llx 0->BUG\n", spte, *spte); |
456 | BUG(); | |
290fc38d | 457 | } else if (!(*rmapp & 1)) { |
cd4a4e53 | 458 | rmap_printk("rmap_remove: %p %llx 1->0\n", spte, *spte); |
290fc38d | 459 | if ((u64 *)*rmapp != spte) { |
cd4a4e53 AK |
460 | printk(KERN_ERR "rmap_remove: %p %llx 1->BUG\n", |
461 | spte, *spte); | |
462 | BUG(); | |
463 | } | |
290fc38d | 464 | *rmapp = 0; |
cd4a4e53 AK |
465 | } else { |
466 | rmap_printk("rmap_remove: %p %llx many->many\n", spte, *spte); | |
290fc38d | 467 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
cd4a4e53 AK |
468 | prev_desc = NULL; |
469 | while (desc) { | |
470 | for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i) | |
471 | if (desc->shadow_ptes[i] == spte) { | |
290fc38d | 472 | rmap_desc_remove_entry(rmapp, |
714b93da | 473 | desc, i, |
cd4a4e53 AK |
474 | prev_desc); |
475 | return; | |
476 | } | |
477 | prev_desc = desc; | |
478 | desc = desc->more; | |
479 | } | |
480 | BUG(); | |
481 | } | |
482 | } | |
483 | ||
98348e95 | 484 | static u64 *rmap_next(struct kvm *kvm, unsigned long *rmapp, u64 *spte) |
374cbac0 | 485 | { |
374cbac0 | 486 | struct kvm_rmap_desc *desc; |
98348e95 IE |
487 | struct kvm_rmap_desc *prev_desc; |
488 | u64 *prev_spte; | |
489 | int i; | |
490 | ||
491 | if (!*rmapp) | |
492 | return NULL; | |
493 | else if (!(*rmapp & 1)) { | |
494 | if (!spte) | |
495 | return (u64 *)*rmapp; | |
496 | return NULL; | |
497 | } | |
498 | desc = (struct kvm_rmap_desc *)(*rmapp & ~1ul); | |
499 | prev_desc = NULL; | |
500 | prev_spte = NULL; | |
501 | while (desc) { | |
502 | for (i = 0; i < RMAP_EXT && desc->shadow_ptes[i]; ++i) { | |
503 | if (prev_spte == spte) | |
504 | return desc->shadow_ptes[i]; | |
505 | prev_spte = desc->shadow_ptes[i]; | |
506 | } | |
507 | desc = desc->more; | |
508 | } | |
509 | return NULL; | |
510 | } | |
511 | ||
512 | static void rmap_write_protect(struct kvm *kvm, u64 gfn) | |
513 | { | |
290fc38d | 514 | unsigned long *rmapp; |
374cbac0 | 515 | u64 *spte; |
caa5b8a5 | 516 | int write_protected = 0; |
374cbac0 | 517 | |
4a4c9924 AL |
518 | gfn = unalias_gfn(kvm, gfn); |
519 | rmapp = gfn_to_rmap(kvm, gfn); | |
374cbac0 | 520 | |
98348e95 IE |
521 | spte = rmap_next(kvm, rmapp, NULL); |
522 | while (spte) { | |
374cbac0 | 523 | BUG_ON(!spte); |
374cbac0 | 524 | BUG_ON(!(*spte & PT_PRESENT_MASK)); |
374cbac0 | 525 | rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); |
caa5b8a5 | 526 | if (is_writeble_pte(*spte)) { |
9647c14c | 527 | set_shadow_pte(spte, *spte & ~PT_WRITABLE_MASK); |
caa5b8a5 ED |
528 | write_protected = 1; |
529 | } | |
9647c14c | 530 | spte = rmap_next(kvm, rmapp, spte); |
374cbac0 | 531 | } |
caa5b8a5 ED |
532 | if (write_protected) |
533 | kvm_flush_remote_tlbs(kvm); | |
374cbac0 AK |
534 | } |
535 | ||
d6c69ee9 | 536 | #ifdef MMU_DEBUG |
47ad8e68 | 537 | static int is_empty_shadow_page(u64 *spt) |
6aa8b732 | 538 | { |
139bdb2d AK |
539 | u64 *pos; |
540 | u64 *end; | |
541 | ||
47ad8e68 | 542 | for (pos = spt, end = pos + PAGE_SIZE / sizeof(u64); pos != end; pos++) |
c7addb90 | 543 | if ((*pos & ~PT_SHADOW_IO_MARK) != shadow_trap_nonpresent_pte) { |
139bdb2d AK |
544 | printk(KERN_ERR "%s: %p %llx\n", __FUNCTION__, |
545 | pos, *pos); | |
6aa8b732 | 546 | return 0; |
139bdb2d | 547 | } |
6aa8b732 AK |
548 | return 1; |
549 | } | |
d6c69ee9 | 550 | #endif |
6aa8b732 | 551 | |
4db35314 | 552 | static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) |
260746c0 | 553 | { |
4db35314 AK |
554 | ASSERT(is_empty_shadow_page(sp->spt)); |
555 | list_del(&sp->link); | |
556 | __free_page(virt_to_page(sp->spt)); | |
557 | __free_page(virt_to_page(sp->gfns)); | |
558 | kfree(sp); | |
f05e70ac | 559 | ++kvm->arch.n_free_mmu_pages; |
260746c0 AK |
560 | } |
561 | ||
cea0f0e7 AK |
562 | static unsigned kvm_page_table_hashfn(gfn_t gfn) |
563 | { | |
564 | return gfn; | |
565 | } | |
566 | ||
25c0de2c AK |
567 | static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, |
568 | u64 *parent_pte) | |
6aa8b732 | 569 | { |
4db35314 | 570 | struct kvm_mmu_page *sp; |
6aa8b732 | 571 | |
f05e70ac | 572 | if (!vcpu->kvm->arch.n_free_mmu_pages) |
25c0de2c | 573 | return NULL; |
6aa8b732 | 574 | |
ad312c7c ZX |
575 | sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache, sizeof *sp); |
576 | sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); | |
577 | sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache, PAGE_SIZE); | |
4db35314 | 578 | set_page_private(virt_to_page(sp->spt), (unsigned long)sp); |
f05e70ac | 579 | list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); |
4db35314 AK |
580 | ASSERT(is_empty_shadow_page(sp->spt)); |
581 | sp->slot_bitmap = 0; | |
582 | sp->multimapped = 0; | |
583 | sp->parent_pte = parent_pte; | |
f05e70ac | 584 | --vcpu->kvm->arch.n_free_mmu_pages; |
4db35314 | 585 | return sp; |
6aa8b732 AK |
586 | } |
587 | ||
714b93da | 588 | static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu, |
4db35314 | 589 | struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 AK |
590 | { |
591 | struct kvm_pte_chain *pte_chain; | |
592 | struct hlist_node *node; | |
593 | int i; | |
594 | ||
595 | if (!parent_pte) | |
596 | return; | |
4db35314 AK |
597 | if (!sp->multimapped) { |
598 | u64 *old = sp->parent_pte; | |
cea0f0e7 AK |
599 | |
600 | if (!old) { | |
4db35314 | 601 | sp->parent_pte = parent_pte; |
cea0f0e7 AK |
602 | return; |
603 | } | |
4db35314 | 604 | sp->multimapped = 1; |
714b93da | 605 | pte_chain = mmu_alloc_pte_chain(vcpu); |
4db35314 AK |
606 | INIT_HLIST_HEAD(&sp->parent_ptes); |
607 | hlist_add_head(&pte_chain->link, &sp->parent_ptes); | |
cea0f0e7 AK |
608 | pte_chain->parent_ptes[0] = old; |
609 | } | |
4db35314 | 610 | hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) { |
cea0f0e7 AK |
611 | if (pte_chain->parent_ptes[NR_PTE_CHAIN_ENTRIES-1]) |
612 | continue; | |
613 | for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) | |
614 | if (!pte_chain->parent_ptes[i]) { | |
615 | pte_chain->parent_ptes[i] = parent_pte; | |
616 | return; | |
617 | } | |
618 | } | |
714b93da | 619 | pte_chain = mmu_alloc_pte_chain(vcpu); |
cea0f0e7 | 620 | BUG_ON(!pte_chain); |
4db35314 | 621 | hlist_add_head(&pte_chain->link, &sp->parent_ptes); |
cea0f0e7 AK |
622 | pte_chain->parent_ptes[0] = parent_pte; |
623 | } | |
624 | ||
4db35314 | 625 | static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, |
cea0f0e7 AK |
626 | u64 *parent_pte) |
627 | { | |
628 | struct kvm_pte_chain *pte_chain; | |
629 | struct hlist_node *node; | |
630 | int i; | |
631 | ||
4db35314 AK |
632 | if (!sp->multimapped) { |
633 | BUG_ON(sp->parent_pte != parent_pte); | |
634 | sp->parent_pte = NULL; | |
cea0f0e7 AK |
635 | return; |
636 | } | |
4db35314 | 637 | hlist_for_each_entry(pte_chain, node, &sp->parent_ptes, link) |
cea0f0e7 AK |
638 | for (i = 0; i < NR_PTE_CHAIN_ENTRIES; ++i) { |
639 | if (!pte_chain->parent_ptes[i]) | |
640 | break; | |
641 | if (pte_chain->parent_ptes[i] != parent_pte) | |
642 | continue; | |
697fe2e2 AK |
643 | while (i + 1 < NR_PTE_CHAIN_ENTRIES |
644 | && pte_chain->parent_ptes[i + 1]) { | |
cea0f0e7 AK |
645 | pte_chain->parent_ptes[i] |
646 | = pte_chain->parent_ptes[i + 1]; | |
647 | ++i; | |
648 | } | |
649 | pte_chain->parent_ptes[i] = NULL; | |
697fe2e2 AK |
650 | if (i == 0) { |
651 | hlist_del(&pte_chain->link); | |
90cb0529 | 652 | mmu_free_pte_chain(pte_chain); |
4db35314 AK |
653 | if (hlist_empty(&sp->parent_ptes)) { |
654 | sp->multimapped = 0; | |
655 | sp->parent_pte = NULL; | |
697fe2e2 AK |
656 | } |
657 | } | |
cea0f0e7 AK |
658 | return; |
659 | } | |
660 | BUG(); | |
661 | } | |
662 | ||
4db35314 | 663 | static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn) |
cea0f0e7 AK |
664 | { |
665 | unsigned index; | |
666 | struct hlist_head *bucket; | |
4db35314 | 667 | struct kvm_mmu_page *sp; |
cea0f0e7 AK |
668 | struct hlist_node *node; |
669 | ||
670 | pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn); | |
671 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 672 | bucket = &kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
673 | hlist_for_each_entry(sp, node, bucket, hash_link) |
674 | if (sp->gfn == gfn && !sp->role.metaphysical) { | |
cea0f0e7 | 675 | pgprintk("%s: found role %x\n", |
4db35314 AK |
676 | __FUNCTION__, sp->role.word); |
677 | return sp; | |
cea0f0e7 AK |
678 | } |
679 | return NULL; | |
680 | } | |
681 | ||
682 | static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, | |
683 | gfn_t gfn, | |
684 | gva_t gaddr, | |
685 | unsigned level, | |
686 | int metaphysical, | |
41074d07 | 687 | unsigned access, |
7819026e MT |
688 | u64 *parent_pte, |
689 | bool *new_page) | |
cea0f0e7 AK |
690 | { |
691 | union kvm_mmu_page_role role; | |
692 | unsigned index; | |
693 | unsigned quadrant; | |
694 | struct hlist_head *bucket; | |
4db35314 | 695 | struct kvm_mmu_page *sp; |
cea0f0e7 AK |
696 | struct hlist_node *node; |
697 | ||
698 | role.word = 0; | |
ad312c7c | 699 | role.glevels = vcpu->arch.mmu.root_level; |
cea0f0e7 AK |
700 | role.level = level; |
701 | role.metaphysical = metaphysical; | |
41074d07 | 702 | role.access = access; |
ad312c7c | 703 | if (vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) { |
cea0f0e7 AK |
704 | quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); |
705 | quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1; | |
706 | role.quadrant = quadrant; | |
707 | } | |
708 | pgprintk("%s: looking gfn %lx role %x\n", __FUNCTION__, | |
709 | gfn, role.word); | |
710 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 711 | bucket = &vcpu->kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
712 | hlist_for_each_entry(sp, node, bucket, hash_link) |
713 | if (sp->gfn == gfn && sp->role.word == role.word) { | |
714 | mmu_page_add_parent_pte(vcpu, sp, parent_pte); | |
cea0f0e7 | 715 | pgprintk("%s: found\n", __FUNCTION__); |
4db35314 | 716 | return sp; |
cea0f0e7 | 717 | } |
4db35314 AK |
718 | sp = kvm_mmu_alloc_page(vcpu, parent_pte); |
719 | if (!sp) | |
720 | return sp; | |
cea0f0e7 | 721 | pgprintk("%s: adding gfn %lx role %x\n", __FUNCTION__, gfn, role.word); |
4db35314 AK |
722 | sp->gfn = gfn; |
723 | sp->role = role; | |
724 | hlist_add_head(&sp->hash_link, bucket); | |
ad312c7c | 725 | vcpu->arch.mmu.prefetch_page(vcpu, sp); |
374cbac0 | 726 | if (!metaphysical) |
4a4c9924 | 727 | rmap_write_protect(vcpu->kvm, gfn); |
7819026e MT |
728 | if (new_page) |
729 | *new_page = 1; | |
4db35314 | 730 | return sp; |
cea0f0e7 AK |
731 | } |
732 | ||
90cb0529 | 733 | static void kvm_mmu_page_unlink_children(struct kvm *kvm, |
4db35314 | 734 | struct kvm_mmu_page *sp) |
a436036b | 735 | { |
697fe2e2 AK |
736 | unsigned i; |
737 | u64 *pt; | |
738 | u64 ent; | |
739 | ||
4db35314 | 740 | pt = sp->spt; |
697fe2e2 | 741 | |
4db35314 | 742 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) { |
697fe2e2 | 743 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { |
c7addb90 | 744 | if (is_shadow_present_pte(pt[i])) |
290fc38d | 745 | rmap_remove(kvm, &pt[i]); |
c7addb90 | 746 | pt[i] = shadow_trap_nonpresent_pte; |
697fe2e2 | 747 | } |
90cb0529 | 748 | kvm_flush_remote_tlbs(kvm); |
697fe2e2 AK |
749 | return; |
750 | } | |
751 | ||
752 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { | |
753 | ent = pt[i]; | |
754 | ||
c7addb90 AK |
755 | pt[i] = shadow_trap_nonpresent_pte; |
756 | if (!is_shadow_present_pte(ent)) | |
697fe2e2 AK |
757 | continue; |
758 | ent &= PT64_BASE_ADDR_MASK; | |
90cb0529 | 759 | mmu_page_remove_parent_pte(page_header(ent), &pt[i]); |
697fe2e2 | 760 | } |
90cb0529 | 761 | kvm_flush_remote_tlbs(kvm); |
a436036b AK |
762 | } |
763 | ||
4db35314 | 764 | static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 | 765 | { |
4db35314 | 766 | mmu_page_remove_parent_pte(sp, parent_pte); |
a436036b AK |
767 | } |
768 | ||
12b7d28f AK |
769 | static void kvm_mmu_reset_last_pte_updated(struct kvm *kvm) |
770 | { | |
771 | int i; | |
772 | ||
773 | for (i = 0; i < KVM_MAX_VCPUS; ++i) | |
774 | if (kvm->vcpus[i]) | |
ad312c7c | 775 | kvm->vcpus[i]->arch.last_pte_updated = NULL; |
12b7d28f AK |
776 | } |
777 | ||
4db35314 | 778 | static void kvm_mmu_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp) |
a436036b AK |
779 | { |
780 | u64 *parent_pte; | |
781 | ||
4cee5764 | 782 | ++kvm->stat.mmu_shadow_zapped; |
4db35314 AK |
783 | while (sp->multimapped || sp->parent_pte) { |
784 | if (!sp->multimapped) | |
785 | parent_pte = sp->parent_pte; | |
a436036b AK |
786 | else { |
787 | struct kvm_pte_chain *chain; | |
788 | ||
4db35314 | 789 | chain = container_of(sp->parent_ptes.first, |
a436036b AK |
790 | struct kvm_pte_chain, link); |
791 | parent_pte = chain->parent_ptes[0]; | |
792 | } | |
697fe2e2 | 793 | BUG_ON(!parent_pte); |
4db35314 | 794 | kvm_mmu_put_page(sp, parent_pte); |
c7addb90 | 795 | set_shadow_pte(parent_pte, shadow_trap_nonpresent_pte); |
a436036b | 796 | } |
4db35314 AK |
797 | kvm_mmu_page_unlink_children(kvm, sp); |
798 | if (!sp->root_count) { | |
799 | hlist_del(&sp->hash_link); | |
800 | kvm_mmu_free_page(kvm, sp); | |
36868f7b | 801 | } else |
f05e70ac | 802 | list_move(&sp->link, &kvm->arch.active_mmu_pages); |
12b7d28f | 803 | kvm_mmu_reset_last_pte_updated(kvm); |
a436036b AK |
804 | } |
805 | ||
82ce2c96 IE |
806 | /* |
807 | * Changing the number of mmu pages allocated to the vm | |
808 | * Note: if kvm_nr_mmu_pages is too small, you will get dead lock | |
809 | */ | |
810 | void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int kvm_nr_mmu_pages) | |
811 | { | |
812 | /* | |
813 | * If we set the number of mmu pages to be smaller be than the | |
814 | * number of actived pages , we must to free some mmu pages before we | |
815 | * change the value | |
816 | */ | |
817 | ||
f05e70ac | 818 | if ((kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages) > |
82ce2c96 | 819 | kvm_nr_mmu_pages) { |
f05e70ac ZX |
820 | int n_used_mmu_pages = kvm->arch.n_alloc_mmu_pages |
821 | - kvm->arch.n_free_mmu_pages; | |
82ce2c96 IE |
822 | |
823 | while (n_used_mmu_pages > kvm_nr_mmu_pages) { | |
824 | struct kvm_mmu_page *page; | |
825 | ||
f05e70ac | 826 | page = container_of(kvm->arch.active_mmu_pages.prev, |
82ce2c96 IE |
827 | struct kvm_mmu_page, link); |
828 | kvm_mmu_zap_page(kvm, page); | |
829 | n_used_mmu_pages--; | |
830 | } | |
f05e70ac | 831 | kvm->arch.n_free_mmu_pages = 0; |
82ce2c96 IE |
832 | } |
833 | else | |
f05e70ac ZX |
834 | kvm->arch.n_free_mmu_pages += kvm_nr_mmu_pages |
835 | - kvm->arch.n_alloc_mmu_pages; | |
82ce2c96 | 836 | |
f05e70ac | 837 | kvm->arch.n_alloc_mmu_pages = kvm_nr_mmu_pages; |
82ce2c96 IE |
838 | } |
839 | ||
f67a46f4 | 840 | static int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) |
a436036b AK |
841 | { |
842 | unsigned index; | |
843 | struct hlist_head *bucket; | |
4db35314 | 844 | struct kvm_mmu_page *sp; |
a436036b AK |
845 | struct hlist_node *node, *n; |
846 | int r; | |
847 | ||
848 | pgprintk("%s: looking for gfn %lx\n", __FUNCTION__, gfn); | |
849 | r = 0; | |
850 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; | |
f05e70ac | 851 | bucket = &kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
852 | hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) |
853 | if (sp->gfn == gfn && !sp->role.metaphysical) { | |
697fe2e2 | 854 | pgprintk("%s: gfn %lx role %x\n", __FUNCTION__, gfn, |
4db35314 AK |
855 | sp->role.word); |
856 | kvm_mmu_zap_page(kvm, sp); | |
a436036b AK |
857 | r = 1; |
858 | } | |
859 | return r; | |
cea0f0e7 AK |
860 | } |
861 | ||
f67a46f4 | 862 | static void mmu_unshadow(struct kvm *kvm, gfn_t gfn) |
97a0a01e | 863 | { |
4db35314 | 864 | struct kvm_mmu_page *sp; |
97a0a01e | 865 | |
4db35314 AK |
866 | while ((sp = kvm_mmu_lookup_page(kvm, gfn)) != NULL) { |
867 | pgprintk("%s: zap %lx %x\n", __FUNCTION__, gfn, sp->role.word); | |
868 | kvm_mmu_zap_page(kvm, sp); | |
97a0a01e AK |
869 | } |
870 | } | |
871 | ||
38c335f1 | 872 | static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn) |
6aa8b732 | 873 | { |
38c335f1 | 874 | int slot = memslot_id(kvm, gfn_to_memslot(kvm, gfn)); |
4db35314 | 875 | struct kvm_mmu_page *sp = page_header(__pa(pte)); |
6aa8b732 | 876 | |
4db35314 | 877 | __set_bit(slot, &sp->slot_bitmap); |
6aa8b732 AK |
878 | } |
879 | ||
039576c0 AK |
880 | struct page *gva_to_page(struct kvm_vcpu *vcpu, gva_t gva) |
881 | { | |
ad312c7c | 882 | gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); |
039576c0 AK |
883 | |
884 | if (gpa == UNMAPPED_GVA) | |
885 | return NULL; | |
1d28f5f4 | 886 | return gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); |
039576c0 AK |
887 | } |
888 | ||
1c4f1fd6 AK |
889 | static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte, |
890 | unsigned pt_access, unsigned pte_access, | |
891 | int user_fault, int write_fault, int dirty, | |
892 | int *ptwrite, gfn_t gfn) | |
893 | { | |
894 | u64 spte; | |
895 | int was_rmapped = is_rmap_pte(*shadow_pte); | |
896 | struct page *page; | |
897 | ||
bc750ba8 | 898 | pgprintk("%s: spte %llx access %x write_fault %d" |
1c4f1fd6 | 899 | " user_fault %d gfn %lx\n", |
bc750ba8 | 900 | __FUNCTION__, *shadow_pte, pt_access, |
1c4f1fd6 AK |
901 | write_fault, user_fault, gfn); |
902 | ||
903 | /* | |
904 | * We don't set the accessed bit, since we sometimes want to see | |
905 | * whether the guest actually used the pte (in order to detect | |
906 | * demand paging). | |
907 | */ | |
908 | spte = PT_PRESENT_MASK | PT_DIRTY_MASK; | |
909 | if (!dirty) | |
910 | pte_access &= ~ACC_WRITE_MASK; | |
911 | if (!(pte_access & ACC_EXEC_MASK)) | |
912 | spte |= PT64_NX_MASK; | |
913 | ||
914 | page = gfn_to_page(vcpu->kvm, gfn); | |
915 | ||
916 | spte |= PT_PRESENT_MASK; | |
917 | if (pte_access & ACC_USER_MASK) | |
918 | spte |= PT_USER_MASK; | |
919 | ||
920 | if (is_error_page(page)) { | |
921 | set_shadow_pte(shadow_pte, | |
922 | shadow_trap_nonpresent_pte | PT_SHADOW_IO_MARK); | |
923 | kvm_release_page_clean(page); | |
924 | return; | |
925 | } | |
926 | ||
927 | spte |= page_to_phys(page); | |
928 | ||
929 | if ((pte_access & ACC_WRITE_MASK) | |
930 | || (write_fault && !is_write_protection(vcpu) && !user_fault)) { | |
931 | struct kvm_mmu_page *shadow; | |
932 | ||
933 | spte |= PT_WRITABLE_MASK; | |
934 | if (user_fault) { | |
935 | mmu_unshadow(vcpu->kvm, gfn); | |
936 | goto unshadowed; | |
937 | } | |
938 | ||
939 | shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn); | |
940 | if (shadow) { | |
941 | pgprintk("%s: found shadow page for %lx, marking ro\n", | |
942 | __FUNCTION__, gfn); | |
943 | pte_access &= ~ACC_WRITE_MASK; | |
944 | if (is_writeble_pte(spte)) { | |
945 | spte &= ~PT_WRITABLE_MASK; | |
946 | kvm_x86_ops->tlb_flush(vcpu); | |
947 | } | |
948 | if (write_fault) | |
949 | *ptwrite = 1; | |
950 | } | |
951 | } | |
952 | ||
953 | unshadowed: | |
954 | ||
955 | if (pte_access & ACC_WRITE_MASK) | |
956 | mark_page_dirty(vcpu->kvm, gfn); | |
957 | ||
958 | pgprintk("%s: setting spte %llx\n", __FUNCTION__, spte); | |
959 | set_shadow_pte(shadow_pte, spte); | |
960 | page_header_update_slot(vcpu->kvm, shadow_pte, gfn); | |
961 | if (!was_rmapped) { | |
962 | rmap_add(vcpu, shadow_pte, gfn); | |
963 | if (!is_rmap_pte(*shadow_pte)) | |
964 | kvm_release_page_clean(page); | |
965 | } | |
966 | else | |
967 | kvm_release_page_clean(page); | |
968 | if (!ptwrite || !*ptwrite) | |
ad312c7c | 969 | vcpu->arch.last_pte_updated = shadow_pte; |
1c4f1fd6 AK |
970 | } |
971 | ||
6aa8b732 AK |
972 | static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) |
973 | { | |
974 | } | |
975 | ||
e833240f | 976 | static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, int write, gfn_t gfn) |
6aa8b732 AK |
977 | { |
978 | int level = PT32E_ROOT_LEVEL; | |
ad312c7c | 979 | hpa_t table_addr = vcpu->arch.mmu.root_hpa; |
e833240f | 980 | int pt_write = 0; |
6aa8b732 AK |
981 | |
982 | for (; ; level--) { | |
983 | u32 index = PT64_INDEX(v, level); | |
984 | u64 *table; | |
985 | ||
986 | ASSERT(VALID_PAGE(table_addr)); | |
987 | table = __va(table_addr); | |
988 | ||
989 | if (level == 1) { | |
e833240f AK |
990 | mmu_set_spte(vcpu, &table[index], ACC_ALL, ACC_ALL, |
991 | 0, write, 1, &pt_write, gfn); | |
992 | return pt_write || is_io_pte(table[index]); | |
6aa8b732 AK |
993 | } |
994 | ||
c7addb90 | 995 | if (table[index] == shadow_trap_nonpresent_pte) { |
25c0de2c | 996 | struct kvm_mmu_page *new_table; |
cea0f0e7 | 997 | gfn_t pseudo_gfn; |
6aa8b732 | 998 | |
cea0f0e7 AK |
999 | pseudo_gfn = (v & PT64_DIR_BASE_ADDR_MASK) |
1000 | >> PAGE_SHIFT; | |
1001 | new_table = kvm_mmu_get_page(vcpu, pseudo_gfn, | |
1002 | v, level - 1, | |
7819026e MT |
1003 | 1, ACC_ALL, &table[index], |
1004 | NULL); | |
25c0de2c | 1005 | if (!new_table) { |
6aa8b732 AK |
1006 | pgprintk("nonpaging_map: ENOMEM\n"); |
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 | ||
c7addb90 AK |
1017 | static void nonpaging_prefetch_page(struct kvm_vcpu *vcpu, |
1018 | struct kvm_mmu_page *sp) | |
1019 | { | |
1020 | int i; | |
1021 | ||
1022 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) | |
1023 | sp->spt[i] = shadow_trap_nonpresent_pte; | |
1024 | } | |
1025 | ||
17ac10ad AK |
1026 | static void mmu_free_roots(struct kvm_vcpu *vcpu) |
1027 | { | |
1028 | int i; | |
4db35314 | 1029 | struct kvm_mmu_page *sp; |
17ac10ad | 1030 | |
ad312c7c | 1031 | if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) |
7b53aa56 | 1032 | return; |
17ac10ad | 1033 | #ifdef CONFIG_X86_64 |
ad312c7c ZX |
1034 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { |
1035 | hpa_t root = vcpu->arch.mmu.root_hpa; | |
17ac10ad | 1036 | |
4db35314 AK |
1037 | sp = page_header(root); |
1038 | --sp->root_count; | |
ad312c7c | 1039 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
17ac10ad AK |
1040 | return; |
1041 | } | |
1042 | #endif | |
1043 | for (i = 0; i < 4; ++i) { | |
ad312c7c | 1044 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad | 1045 | |
417726a3 | 1046 | if (root) { |
417726a3 | 1047 | root &= PT64_BASE_ADDR_MASK; |
4db35314 AK |
1048 | sp = page_header(root); |
1049 | --sp->root_count; | |
417726a3 | 1050 | } |
ad312c7c | 1051 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 1052 | } |
ad312c7c | 1053 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
17ac10ad AK |
1054 | } |
1055 | ||
1056 | static void mmu_alloc_roots(struct kvm_vcpu *vcpu) | |
1057 | { | |
1058 | int i; | |
cea0f0e7 | 1059 | gfn_t root_gfn; |
4db35314 | 1060 | struct kvm_mmu_page *sp; |
3bb65a22 | 1061 | |
ad312c7c | 1062 | root_gfn = vcpu->arch.cr3 >> PAGE_SHIFT; |
17ac10ad AK |
1063 | |
1064 | #ifdef CONFIG_X86_64 | |
ad312c7c ZX |
1065 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { |
1066 | hpa_t root = vcpu->arch.mmu.root_hpa; | |
17ac10ad AK |
1067 | |
1068 | ASSERT(!VALID_PAGE(root)); | |
4db35314 | 1069 | sp = kvm_mmu_get_page(vcpu, root_gfn, 0, |
7819026e | 1070 | PT64_ROOT_LEVEL, 0, ACC_ALL, NULL, NULL); |
4db35314 AK |
1071 | root = __pa(sp->spt); |
1072 | ++sp->root_count; | |
ad312c7c | 1073 | vcpu->arch.mmu.root_hpa = root; |
17ac10ad AK |
1074 | return; |
1075 | } | |
1076 | #endif | |
1077 | for (i = 0; i < 4; ++i) { | |
ad312c7c | 1078 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad AK |
1079 | |
1080 | ASSERT(!VALID_PAGE(root)); | |
ad312c7c ZX |
1081 | if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) { |
1082 | if (!is_present_pte(vcpu->arch.pdptrs[i])) { | |
1083 | vcpu->arch.mmu.pae_root[i] = 0; | |
417726a3 AK |
1084 | continue; |
1085 | } | |
ad312c7c ZX |
1086 | root_gfn = vcpu->arch.pdptrs[i] >> PAGE_SHIFT; |
1087 | } else if (vcpu->arch.mmu.root_level == 0) | |
cea0f0e7 | 1088 | root_gfn = 0; |
4db35314 AK |
1089 | sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, |
1090 | PT32_ROOT_LEVEL, !is_paging(vcpu), | |
7819026e | 1091 | ACC_ALL, NULL, NULL); |
4db35314 AK |
1092 | root = __pa(sp->spt); |
1093 | ++sp->root_count; | |
ad312c7c | 1094 | vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; |
17ac10ad | 1095 | } |
ad312c7c | 1096 | vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); |
17ac10ad AK |
1097 | } |
1098 | ||
6aa8b732 AK |
1099 | static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr) |
1100 | { | |
1101 | return vaddr; | |
1102 | } | |
1103 | ||
1104 | static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, | |
3f3e7124 | 1105 | u32 error_code) |
6aa8b732 | 1106 | { |
e833240f | 1107 | gfn_t gfn; |
e2dec939 | 1108 | int r; |
6aa8b732 | 1109 | |
e833240f | 1110 | pgprintk("%s: gva %lx error %x\n", __FUNCTION__, gva, error_code); |
e2dec939 AK |
1111 | r = mmu_topup_memory_caches(vcpu); |
1112 | if (r) | |
1113 | return r; | |
714b93da | 1114 | |
6aa8b732 | 1115 | ASSERT(vcpu); |
ad312c7c | 1116 | ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 | 1117 | |
e833240f | 1118 | gfn = gva >> PAGE_SHIFT; |
6aa8b732 | 1119 | |
e833240f AK |
1120 | return nonpaging_map(vcpu, gva & PAGE_MASK, |
1121 | error_code & PFERR_WRITE_MASK, gfn); | |
6aa8b732 AK |
1122 | } |
1123 | ||
6aa8b732 AK |
1124 | static void nonpaging_free(struct kvm_vcpu *vcpu) |
1125 | { | |
17ac10ad | 1126 | mmu_free_roots(vcpu); |
6aa8b732 AK |
1127 | } |
1128 | ||
1129 | static int nonpaging_init_context(struct kvm_vcpu *vcpu) | |
1130 | { | |
ad312c7c | 1131 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1132 | |
1133 | context->new_cr3 = nonpaging_new_cr3; | |
1134 | context->page_fault = nonpaging_page_fault; | |
6aa8b732 AK |
1135 | context->gva_to_gpa = nonpaging_gva_to_gpa; |
1136 | context->free = nonpaging_free; | |
c7addb90 | 1137 | context->prefetch_page = nonpaging_prefetch_page; |
cea0f0e7 | 1138 | context->root_level = 0; |
6aa8b732 | 1139 | context->shadow_root_level = PT32E_ROOT_LEVEL; |
17c3ba9d | 1140 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1141 | return 0; |
1142 | } | |
1143 | ||
d835dfec | 1144 | void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu) |
6aa8b732 | 1145 | { |
1165f5fe | 1146 | ++vcpu->stat.tlb_flush; |
cbdd1bea | 1147 | kvm_x86_ops->tlb_flush(vcpu); |
6aa8b732 AK |
1148 | } |
1149 | ||
1150 | static void paging_new_cr3(struct kvm_vcpu *vcpu) | |
1151 | { | |
374cbac0 | 1152 | pgprintk("%s: cr3 %lx\n", __FUNCTION__, vcpu->cr3); |
cea0f0e7 | 1153 | mmu_free_roots(vcpu); |
6aa8b732 AK |
1154 | } |
1155 | ||
6aa8b732 AK |
1156 | static void inject_page_fault(struct kvm_vcpu *vcpu, |
1157 | u64 addr, | |
1158 | u32 err_code) | |
1159 | { | |
c3c91fee | 1160 | kvm_inject_page_fault(vcpu, addr, err_code); |
6aa8b732 AK |
1161 | } |
1162 | ||
6aa8b732 AK |
1163 | static void paging_free(struct kvm_vcpu *vcpu) |
1164 | { | |
1165 | nonpaging_free(vcpu); | |
1166 | } | |
1167 | ||
1168 | #define PTTYPE 64 | |
1169 | #include "paging_tmpl.h" | |
1170 | #undef PTTYPE | |
1171 | ||
1172 | #define PTTYPE 32 | |
1173 | #include "paging_tmpl.h" | |
1174 | #undef PTTYPE | |
1175 | ||
17ac10ad | 1176 | static int paging64_init_context_common(struct kvm_vcpu *vcpu, int level) |
6aa8b732 | 1177 | { |
ad312c7c | 1178 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1179 | |
1180 | ASSERT(is_pae(vcpu)); | |
1181 | context->new_cr3 = paging_new_cr3; | |
1182 | context->page_fault = paging64_page_fault; | |
6aa8b732 | 1183 | context->gva_to_gpa = paging64_gva_to_gpa; |
c7addb90 | 1184 | context->prefetch_page = paging64_prefetch_page; |
6aa8b732 | 1185 | context->free = paging_free; |
17ac10ad AK |
1186 | context->root_level = level; |
1187 | context->shadow_root_level = level; | |
17c3ba9d | 1188 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1189 | return 0; |
1190 | } | |
1191 | ||
17ac10ad AK |
1192 | static int paging64_init_context(struct kvm_vcpu *vcpu) |
1193 | { | |
1194 | return paging64_init_context_common(vcpu, PT64_ROOT_LEVEL); | |
1195 | } | |
1196 | ||
6aa8b732 AK |
1197 | static int paging32_init_context(struct kvm_vcpu *vcpu) |
1198 | { | |
ad312c7c | 1199 | struct kvm_mmu *context = &vcpu->arch.mmu; |
6aa8b732 AK |
1200 | |
1201 | context->new_cr3 = paging_new_cr3; | |
1202 | context->page_fault = paging32_page_fault; | |
6aa8b732 AK |
1203 | context->gva_to_gpa = paging32_gva_to_gpa; |
1204 | context->free = paging_free; | |
c7addb90 | 1205 | context->prefetch_page = paging32_prefetch_page; |
6aa8b732 AK |
1206 | context->root_level = PT32_ROOT_LEVEL; |
1207 | context->shadow_root_level = PT32E_ROOT_LEVEL; | |
17c3ba9d | 1208 | context->root_hpa = INVALID_PAGE; |
6aa8b732 AK |
1209 | return 0; |
1210 | } | |
1211 | ||
1212 | static int paging32E_init_context(struct kvm_vcpu *vcpu) | |
1213 | { | |
17ac10ad | 1214 | return paging64_init_context_common(vcpu, PT32E_ROOT_LEVEL); |
6aa8b732 AK |
1215 | } |
1216 | ||
1217 | static int init_kvm_mmu(struct kvm_vcpu *vcpu) | |
1218 | { | |
1219 | ASSERT(vcpu); | |
ad312c7c | 1220 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 AK |
1221 | |
1222 | if (!is_paging(vcpu)) | |
1223 | return nonpaging_init_context(vcpu); | |
a9058ecd | 1224 | else if (is_long_mode(vcpu)) |
6aa8b732 AK |
1225 | return paging64_init_context(vcpu); |
1226 | else if (is_pae(vcpu)) | |
1227 | return paging32E_init_context(vcpu); | |
1228 | else | |
1229 | return paging32_init_context(vcpu); | |
1230 | } | |
1231 | ||
1232 | static void destroy_kvm_mmu(struct kvm_vcpu *vcpu) | |
1233 | { | |
1234 | ASSERT(vcpu); | |
ad312c7c ZX |
1235 | if (VALID_PAGE(vcpu->arch.mmu.root_hpa)) { |
1236 | vcpu->arch.mmu.free(vcpu); | |
1237 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; | |
6aa8b732 AK |
1238 | } |
1239 | } | |
1240 | ||
1241 | int kvm_mmu_reset_context(struct kvm_vcpu *vcpu) | |
17c3ba9d AK |
1242 | { |
1243 | destroy_kvm_mmu(vcpu); | |
1244 | return init_kvm_mmu(vcpu); | |
1245 | } | |
8668a3c4 | 1246 | EXPORT_SYMBOL_GPL(kvm_mmu_reset_context); |
17c3ba9d AK |
1247 | |
1248 | int kvm_mmu_load(struct kvm_vcpu *vcpu) | |
6aa8b732 | 1249 | { |
714b93da AK |
1250 | int r; |
1251 | ||
11ec2804 | 1252 | mutex_lock(&vcpu->kvm->lock); |
e2dec939 | 1253 | r = mmu_topup_memory_caches(vcpu); |
17c3ba9d AK |
1254 | if (r) |
1255 | goto out; | |
1256 | mmu_alloc_roots(vcpu); | |
ad312c7c | 1257 | kvm_x86_ops->set_cr3(vcpu, vcpu->arch.mmu.root_hpa); |
17c3ba9d | 1258 | kvm_mmu_flush_tlb(vcpu); |
714b93da | 1259 | out: |
11ec2804 | 1260 | mutex_unlock(&vcpu->kvm->lock); |
714b93da | 1261 | return r; |
6aa8b732 | 1262 | } |
17c3ba9d AK |
1263 | EXPORT_SYMBOL_GPL(kvm_mmu_load); |
1264 | ||
1265 | void kvm_mmu_unload(struct kvm_vcpu *vcpu) | |
1266 | { | |
1267 | mmu_free_roots(vcpu); | |
1268 | } | |
6aa8b732 | 1269 | |
09072daf | 1270 | static void mmu_pte_write_zap_pte(struct kvm_vcpu *vcpu, |
4db35314 | 1271 | struct kvm_mmu_page *sp, |
ac1b714e AK |
1272 | u64 *spte) |
1273 | { | |
1274 | u64 pte; | |
1275 | struct kvm_mmu_page *child; | |
1276 | ||
1277 | pte = *spte; | |
c7addb90 | 1278 | if (is_shadow_present_pte(pte)) { |
4db35314 | 1279 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) |
290fc38d | 1280 | rmap_remove(vcpu->kvm, spte); |
ac1b714e AK |
1281 | else { |
1282 | child = page_header(pte & PT64_BASE_ADDR_MASK); | |
90cb0529 | 1283 | mmu_page_remove_parent_pte(child, spte); |
ac1b714e AK |
1284 | } |
1285 | } | |
c7addb90 | 1286 | set_shadow_pte(spte, shadow_trap_nonpresent_pte); |
ac1b714e AK |
1287 | } |
1288 | ||
0028425f | 1289 | static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, |
4db35314 | 1290 | struct kvm_mmu_page *sp, |
0028425f | 1291 | u64 *spte, |
c7addb90 AK |
1292 | const void *new, int bytes, |
1293 | int offset_in_pte) | |
0028425f | 1294 | { |
4db35314 | 1295 | if (sp->role.level != PT_PAGE_TABLE_LEVEL) { |
4cee5764 | 1296 | ++vcpu->kvm->stat.mmu_pde_zapped; |
0028425f | 1297 | return; |
4cee5764 | 1298 | } |
0028425f | 1299 | |
4cee5764 | 1300 | ++vcpu->kvm->stat.mmu_pte_updated; |
4db35314 AK |
1301 | if (sp->role.glevels == PT32_ROOT_LEVEL) |
1302 | paging32_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); | |
0028425f | 1303 | else |
4db35314 | 1304 | paging64_update_pte(vcpu, sp, spte, new, bytes, offset_in_pte); |
0028425f AK |
1305 | } |
1306 | ||
79539cec AK |
1307 | static bool need_remote_flush(u64 old, u64 new) |
1308 | { | |
1309 | if (!is_shadow_present_pte(old)) | |
1310 | return false; | |
1311 | if (!is_shadow_present_pte(new)) | |
1312 | return true; | |
1313 | if ((old ^ new) & PT64_BASE_ADDR_MASK) | |
1314 | return true; | |
1315 | old ^= PT64_NX_MASK; | |
1316 | new ^= PT64_NX_MASK; | |
1317 | return (old & ~new & PT64_PERM_MASK) != 0; | |
1318 | } | |
1319 | ||
1320 | static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, u64 old, u64 new) | |
1321 | { | |
1322 | if (need_remote_flush(old, new)) | |
1323 | kvm_flush_remote_tlbs(vcpu->kvm); | |
1324 | else | |
1325 | kvm_mmu_flush_tlb(vcpu); | |
1326 | } | |
1327 | ||
12b7d28f AK |
1328 | static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) |
1329 | { | |
ad312c7c | 1330 | u64 *spte = vcpu->arch.last_pte_updated; |
12b7d28f AK |
1331 | |
1332 | return !!(spte && (*spte & PT_ACCESSED_MASK)); | |
1333 | } | |
1334 | ||
09072daf | 1335 | void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, |
fe551881 | 1336 | const u8 *new, int bytes) |
da4a00f0 | 1337 | { |
9b7a0325 | 1338 | gfn_t gfn = gpa >> PAGE_SHIFT; |
4db35314 | 1339 | struct kvm_mmu_page *sp; |
0e7bc4b9 | 1340 | struct hlist_node *node, *n; |
9b7a0325 AK |
1341 | struct hlist_head *bucket; |
1342 | unsigned index; | |
79539cec | 1343 | u64 entry; |
9b7a0325 | 1344 | u64 *spte; |
9b7a0325 | 1345 | unsigned offset = offset_in_page(gpa); |
0e7bc4b9 | 1346 | unsigned pte_size; |
9b7a0325 | 1347 | unsigned page_offset; |
0e7bc4b9 | 1348 | unsigned misaligned; |
fce0657f | 1349 | unsigned quadrant; |
9b7a0325 | 1350 | int level; |
86a5ba02 | 1351 | int flooded = 0; |
ac1b714e | 1352 | int npte; |
9b7a0325 | 1353 | |
da4a00f0 | 1354 | pgprintk("%s: gpa %llx bytes %d\n", __FUNCTION__, gpa, bytes); |
4cee5764 | 1355 | ++vcpu->kvm->stat.mmu_pte_write; |
c7addb90 | 1356 | kvm_mmu_audit(vcpu, "pre pte write"); |
ad312c7c | 1357 | if (gfn == vcpu->arch.last_pt_write_gfn |
12b7d28f | 1358 | && !last_updated_pte_accessed(vcpu)) { |
ad312c7c ZX |
1359 | ++vcpu->arch.last_pt_write_count; |
1360 | if (vcpu->arch.last_pt_write_count >= 3) | |
86a5ba02 AK |
1361 | flooded = 1; |
1362 | } else { | |
ad312c7c ZX |
1363 | vcpu->arch.last_pt_write_gfn = gfn; |
1364 | vcpu->arch.last_pt_write_count = 1; | |
1365 | vcpu->arch.last_pte_updated = NULL; | |
86a5ba02 | 1366 | } |
9b7a0325 | 1367 | index = kvm_page_table_hashfn(gfn) % KVM_NUM_MMU_PAGES; |
f05e70ac | 1368 | bucket = &vcpu->kvm->arch.mmu_page_hash[index]; |
4db35314 AK |
1369 | hlist_for_each_entry_safe(sp, node, n, bucket, hash_link) { |
1370 | if (sp->gfn != gfn || sp->role.metaphysical) | |
9b7a0325 | 1371 | continue; |
4db35314 | 1372 | pte_size = sp->role.glevels == PT32_ROOT_LEVEL ? 4 : 8; |
0e7bc4b9 | 1373 | misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); |
e925c5ba | 1374 | misaligned |= bytes < 4; |
86a5ba02 | 1375 | if (misaligned || flooded) { |
0e7bc4b9 AK |
1376 | /* |
1377 | * Misaligned accesses are too much trouble to fix | |
1378 | * up; also, they usually indicate a page is not used | |
1379 | * as a page table. | |
86a5ba02 AK |
1380 | * |
1381 | * If we're seeing too many writes to a page, | |
1382 | * it may no longer be a page table, or we may be | |
1383 | * forking, in which case it is better to unmap the | |
1384 | * page. | |
0e7bc4b9 AK |
1385 | */ |
1386 | pgprintk("misaligned: gpa %llx bytes %d role %x\n", | |
4db35314 AK |
1387 | gpa, bytes, sp->role.word); |
1388 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
4cee5764 | 1389 | ++vcpu->kvm->stat.mmu_flooded; |
0e7bc4b9 AK |
1390 | continue; |
1391 | } | |
9b7a0325 | 1392 | page_offset = offset; |
4db35314 | 1393 | level = sp->role.level; |
ac1b714e | 1394 | npte = 1; |
4db35314 | 1395 | if (sp->role.glevels == PT32_ROOT_LEVEL) { |
ac1b714e AK |
1396 | page_offset <<= 1; /* 32->64 */ |
1397 | /* | |
1398 | * A 32-bit pde maps 4MB while the shadow pdes map | |
1399 | * only 2MB. So we need to double the offset again | |
1400 | * and zap two pdes instead of one. | |
1401 | */ | |
1402 | if (level == PT32_ROOT_LEVEL) { | |
6b8d0f9b | 1403 | page_offset &= ~7; /* kill rounding error */ |
ac1b714e AK |
1404 | page_offset <<= 1; |
1405 | npte = 2; | |
1406 | } | |
fce0657f | 1407 | quadrant = page_offset >> PAGE_SHIFT; |
9b7a0325 | 1408 | page_offset &= ~PAGE_MASK; |
4db35314 | 1409 | if (quadrant != sp->role.quadrant) |
fce0657f | 1410 | continue; |
9b7a0325 | 1411 | } |
4db35314 | 1412 | spte = &sp->spt[page_offset / sizeof(*spte)]; |
ac1b714e | 1413 | while (npte--) { |
79539cec | 1414 | entry = *spte; |
4db35314 AK |
1415 | mmu_pte_write_zap_pte(vcpu, sp, spte); |
1416 | mmu_pte_write_new_pte(vcpu, sp, spte, new, bytes, | |
c7addb90 | 1417 | page_offset & (pte_size - 1)); |
79539cec | 1418 | mmu_pte_write_flush_tlb(vcpu, entry, *spte); |
ac1b714e | 1419 | ++spte; |
9b7a0325 | 1420 | } |
9b7a0325 | 1421 | } |
c7addb90 | 1422 | kvm_mmu_audit(vcpu, "post pte write"); |
da4a00f0 AK |
1423 | } |
1424 | ||
a436036b AK |
1425 | int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) |
1426 | { | |
ad312c7c | 1427 | gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, gva); |
a436036b | 1428 | |
f67a46f4 | 1429 | return kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT); |
a436036b AK |
1430 | } |
1431 | ||
22d95b12 | 1432 | void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) |
ebeace86 | 1433 | { |
f05e70ac | 1434 | while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) { |
4db35314 | 1435 | struct kvm_mmu_page *sp; |
ebeace86 | 1436 | |
f05e70ac | 1437 | sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev, |
4db35314 AK |
1438 | struct kvm_mmu_page, link); |
1439 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
4cee5764 | 1440 | ++vcpu->kvm->stat.mmu_recycled; |
ebeace86 AK |
1441 | } |
1442 | } | |
ebeace86 | 1443 | |
3067714c AK |
1444 | int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code) |
1445 | { | |
1446 | int r; | |
1447 | enum emulation_result er; | |
1448 | ||
1449 | mutex_lock(&vcpu->kvm->lock); | |
ad312c7c | 1450 | r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code); |
3067714c AK |
1451 | if (r < 0) |
1452 | goto out; | |
1453 | ||
1454 | if (!r) { | |
1455 | r = 1; | |
1456 | goto out; | |
1457 | } | |
1458 | ||
b733bfb5 AK |
1459 | r = mmu_topup_memory_caches(vcpu); |
1460 | if (r) | |
1461 | goto out; | |
1462 | ||
3067714c AK |
1463 | er = emulate_instruction(vcpu, vcpu->run, cr2, error_code, 0); |
1464 | mutex_unlock(&vcpu->kvm->lock); | |
1465 | ||
1466 | switch (er) { | |
1467 | case EMULATE_DONE: | |
1468 | return 1; | |
1469 | case EMULATE_DO_MMIO: | |
1470 | ++vcpu->stat.mmio_exits; | |
1471 | return 0; | |
1472 | case EMULATE_FAIL: | |
1473 | kvm_report_emulation_failure(vcpu, "pagetable"); | |
1474 | return 1; | |
1475 | default: | |
1476 | BUG(); | |
1477 | } | |
1478 | out: | |
1479 | mutex_unlock(&vcpu->kvm->lock); | |
1480 | return r; | |
1481 | } | |
1482 | EXPORT_SYMBOL_GPL(kvm_mmu_page_fault); | |
1483 | ||
6aa8b732 AK |
1484 | static void free_mmu_pages(struct kvm_vcpu *vcpu) |
1485 | { | |
4db35314 | 1486 | struct kvm_mmu_page *sp; |
6aa8b732 | 1487 | |
f05e70ac ZX |
1488 | while (!list_empty(&vcpu->kvm->arch.active_mmu_pages)) { |
1489 | sp = container_of(vcpu->kvm->arch.active_mmu_pages.next, | |
4db35314 AK |
1490 | struct kvm_mmu_page, link); |
1491 | kvm_mmu_zap_page(vcpu->kvm, sp); | |
f51234c2 | 1492 | } |
ad312c7c | 1493 | free_page((unsigned long)vcpu->arch.mmu.pae_root); |
6aa8b732 AK |
1494 | } |
1495 | ||
1496 | static int alloc_mmu_pages(struct kvm_vcpu *vcpu) | |
1497 | { | |
17ac10ad | 1498 | struct page *page; |
6aa8b732 AK |
1499 | int i; |
1500 | ||
1501 | ASSERT(vcpu); | |
1502 | ||
f05e70ac ZX |
1503 | if (vcpu->kvm->arch.n_requested_mmu_pages) |
1504 | vcpu->kvm->arch.n_free_mmu_pages = | |
1505 | vcpu->kvm->arch.n_requested_mmu_pages; | |
82ce2c96 | 1506 | else |
f05e70ac ZX |
1507 | vcpu->kvm->arch.n_free_mmu_pages = |
1508 | vcpu->kvm->arch.n_alloc_mmu_pages; | |
17ac10ad AK |
1509 | /* |
1510 | * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. | |
1511 | * Therefore we need to allocate shadow page tables in the first | |
1512 | * 4GB of memory, which happens to fit the DMA32 zone. | |
1513 | */ | |
1514 | page = alloc_page(GFP_KERNEL | __GFP_DMA32); | |
1515 | if (!page) | |
1516 | goto error_1; | |
ad312c7c | 1517 | vcpu->arch.mmu.pae_root = page_address(page); |
17ac10ad | 1518 | for (i = 0; i < 4; ++i) |
ad312c7c | 1519 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 1520 | |
6aa8b732 AK |
1521 | return 0; |
1522 | ||
1523 | error_1: | |
1524 | free_mmu_pages(vcpu); | |
1525 | return -ENOMEM; | |
1526 | } | |
1527 | ||
8018c27b | 1528 | int kvm_mmu_create(struct kvm_vcpu *vcpu) |
6aa8b732 | 1529 | { |
6aa8b732 | 1530 | ASSERT(vcpu); |
ad312c7c | 1531 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 | 1532 | |
8018c27b IM |
1533 | return alloc_mmu_pages(vcpu); |
1534 | } | |
6aa8b732 | 1535 | |
8018c27b IM |
1536 | int kvm_mmu_setup(struct kvm_vcpu *vcpu) |
1537 | { | |
1538 | ASSERT(vcpu); | |
ad312c7c | 1539 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
2c264957 | 1540 | |
8018c27b | 1541 | return init_kvm_mmu(vcpu); |
6aa8b732 AK |
1542 | } |
1543 | ||
1544 | void kvm_mmu_destroy(struct kvm_vcpu *vcpu) | |
1545 | { | |
1546 | ASSERT(vcpu); | |
1547 | ||
1548 | destroy_kvm_mmu(vcpu); | |
1549 | free_mmu_pages(vcpu); | |
714b93da | 1550 | mmu_free_memory_caches(vcpu); |
6aa8b732 AK |
1551 | } |
1552 | ||
90cb0529 | 1553 | void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) |
6aa8b732 | 1554 | { |
4db35314 | 1555 | struct kvm_mmu_page *sp; |
6aa8b732 | 1556 | |
f05e70ac | 1557 | list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) { |
6aa8b732 AK |
1558 | int i; |
1559 | u64 *pt; | |
1560 | ||
4db35314 | 1561 | if (!test_bit(slot, &sp->slot_bitmap)) |
6aa8b732 AK |
1562 | continue; |
1563 | ||
4db35314 | 1564 | pt = sp->spt; |
6aa8b732 AK |
1565 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) |
1566 | /* avoid RMW */ | |
9647c14c | 1567 | if (pt[i] & PT_WRITABLE_MASK) |
6aa8b732 | 1568 | pt[i] &= ~PT_WRITABLE_MASK; |
6aa8b732 AK |
1569 | } |
1570 | } | |
37a7d8b0 | 1571 | |
90cb0529 | 1572 | void kvm_mmu_zap_all(struct kvm *kvm) |
e0fa826f | 1573 | { |
4db35314 | 1574 | struct kvm_mmu_page *sp, *node; |
e0fa826f | 1575 | |
f05e70ac | 1576 | list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) |
4db35314 | 1577 | kvm_mmu_zap_page(kvm, sp); |
e0fa826f | 1578 | |
90cb0529 | 1579 | kvm_flush_remote_tlbs(kvm); |
e0fa826f DL |
1580 | } |
1581 | ||
b5a33a75 AK |
1582 | void kvm_mmu_module_exit(void) |
1583 | { | |
1584 | if (pte_chain_cache) | |
1585 | kmem_cache_destroy(pte_chain_cache); | |
1586 | if (rmap_desc_cache) | |
1587 | kmem_cache_destroy(rmap_desc_cache); | |
d3d25b04 AK |
1588 | if (mmu_page_header_cache) |
1589 | kmem_cache_destroy(mmu_page_header_cache); | |
b5a33a75 AK |
1590 | } |
1591 | ||
1592 | int kvm_mmu_module_init(void) | |
1593 | { | |
1594 | pte_chain_cache = kmem_cache_create("kvm_pte_chain", | |
1595 | sizeof(struct kvm_pte_chain), | |
20c2df83 | 1596 | 0, 0, NULL); |
b5a33a75 AK |
1597 | if (!pte_chain_cache) |
1598 | goto nomem; | |
1599 | rmap_desc_cache = kmem_cache_create("kvm_rmap_desc", | |
1600 | sizeof(struct kvm_rmap_desc), | |
20c2df83 | 1601 | 0, 0, NULL); |
b5a33a75 AK |
1602 | if (!rmap_desc_cache) |
1603 | goto nomem; | |
1604 | ||
d3d25b04 AK |
1605 | mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header", |
1606 | sizeof(struct kvm_mmu_page), | |
20c2df83 | 1607 | 0, 0, NULL); |
d3d25b04 AK |
1608 | if (!mmu_page_header_cache) |
1609 | goto nomem; | |
1610 | ||
b5a33a75 AK |
1611 | return 0; |
1612 | ||
1613 | nomem: | |
1614 | kvm_mmu_module_exit(); | |
1615 | return -ENOMEM; | |
1616 | } | |
1617 | ||
3ad82a7e ZX |
1618 | /* |
1619 | * Caculate mmu pages needed for kvm. | |
1620 | */ | |
1621 | unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) | |
1622 | { | |
1623 | int i; | |
1624 | unsigned int nr_mmu_pages; | |
1625 | unsigned int nr_pages = 0; | |
1626 | ||
1627 | for (i = 0; i < kvm->nmemslots; i++) | |
1628 | nr_pages += kvm->memslots[i].npages; | |
1629 | ||
1630 | nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; | |
1631 | nr_mmu_pages = max(nr_mmu_pages, | |
1632 | (unsigned int) KVM_MIN_ALLOC_MMU_PAGES); | |
1633 | ||
1634 | return nr_mmu_pages; | |
1635 | } | |
1636 | ||
37a7d8b0 AK |
1637 | #ifdef AUDIT |
1638 | ||
1639 | static const char *audit_msg; | |
1640 | ||
1641 | static gva_t canonicalize(gva_t gva) | |
1642 | { | |
1643 | #ifdef CONFIG_X86_64 | |
1644 | gva = (long long)(gva << 16) >> 16; | |
1645 | #endif | |
1646 | return gva; | |
1647 | } | |
1648 | ||
1649 | static void audit_mappings_page(struct kvm_vcpu *vcpu, u64 page_pte, | |
1650 | gva_t va, int level) | |
1651 | { | |
1652 | u64 *pt = __va(page_pte & PT64_BASE_ADDR_MASK); | |
1653 | int i; | |
1654 | gva_t va_delta = 1ul << (PAGE_SHIFT + 9 * (level - 1)); | |
1655 | ||
1656 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i, va += va_delta) { | |
1657 | u64 ent = pt[i]; | |
1658 | ||
c7addb90 | 1659 | if (ent == shadow_trap_nonpresent_pte) |
37a7d8b0 AK |
1660 | continue; |
1661 | ||
1662 | va = canonicalize(va); | |
c7addb90 AK |
1663 | if (level > 1) { |
1664 | if (ent == shadow_notrap_nonpresent_pte) | |
1665 | printk(KERN_ERR "audit: (%s) nontrapping pte" | |
1666 | " in nonleaf level: levels %d gva %lx" | |
1667 | " level %d pte %llx\n", audit_msg, | |
ad312c7c | 1668 | vcpu->arch.mmu.root_level, va, level, ent); |
c7addb90 | 1669 | |
37a7d8b0 | 1670 | audit_mappings_page(vcpu, ent, va, level - 1); |
c7addb90 | 1671 | } else { |
ad312c7c | 1672 | gpa_t gpa = vcpu->arch.mmu.gva_to_gpa(vcpu, va); |
1d28f5f4 AK |
1673 | struct page *page = gpa_to_page(vcpu, gpa); |
1674 | hpa_t hpa = page_to_phys(page); | |
37a7d8b0 | 1675 | |
c7addb90 | 1676 | if (is_shadow_present_pte(ent) |
37a7d8b0 | 1677 | && (ent & PT64_BASE_ADDR_MASK) != hpa) |
c7addb90 AK |
1678 | printk(KERN_ERR "xx audit error: (%s) levels %d" |
1679 | " gva %lx gpa %llx hpa %llx ent %llx %d\n", | |
ad312c7c | 1680 | audit_msg, vcpu->arch.mmu.root_level, |
d77c26fc MD |
1681 | va, gpa, hpa, ent, |
1682 | is_shadow_present_pte(ent)); | |
c7addb90 AK |
1683 | else if (ent == shadow_notrap_nonpresent_pte |
1684 | && !is_error_hpa(hpa)) | |
1685 | printk(KERN_ERR "audit: (%s) notrap shadow," | |
1686 | " valid guest gva %lx\n", audit_msg, va); | |
b4231d61 | 1687 | kvm_release_page_clean(page); |
c7addb90 | 1688 | |
37a7d8b0 AK |
1689 | } |
1690 | } | |
1691 | } | |
1692 | ||
1693 | static void audit_mappings(struct kvm_vcpu *vcpu) | |
1694 | { | |
1ea252af | 1695 | unsigned i; |
37a7d8b0 | 1696 | |
ad312c7c ZX |
1697 | if (vcpu->arch.mmu.root_level == 4) |
1698 | audit_mappings_page(vcpu, vcpu->arch.mmu.root_hpa, 0, 4); | |
37a7d8b0 AK |
1699 | else |
1700 | for (i = 0; i < 4; ++i) | |
ad312c7c | 1701 | if (vcpu->arch.mmu.pae_root[i] & PT_PRESENT_MASK) |
37a7d8b0 | 1702 | audit_mappings_page(vcpu, |
ad312c7c | 1703 | vcpu->arch.mmu.pae_root[i], |
37a7d8b0 AK |
1704 | i << 30, |
1705 | 2); | |
1706 | } | |
1707 | ||
1708 | static int count_rmaps(struct kvm_vcpu *vcpu) | |
1709 | { | |
1710 | int nmaps = 0; | |
1711 | int i, j, k; | |
1712 | ||
1713 | for (i = 0; i < KVM_MEMORY_SLOTS; ++i) { | |
1714 | struct kvm_memory_slot *m = &vcpu->kvm->memslots[i]; | |
1715 | struct kvm_rmap_desc *d; | |
1716 | ||
1717 | for (j = 0; j < m->npages; ++j) { | |
290fc38d | 1718 | unsigned long *rmapp = &m->rmap[j]; |
37a7d8b0 | 1719 | |
290fc38d | 1720 | if (!*rmapp) |
37a7d8b0 | 1721 | continue; |
290fc38d | 1722 | if (!(*rmapp & 1)) { |
37a7d8b0 AK |
1723 | ++nmaps; |
1724 | continue; | |
1725 | } | |
290fc38d | 1726 | d = (struct kvm_rmap_desc *)(*rmapp & ~1ul); |
37a7d8b0 AK |
1727 | while (d) { |
1728 | for (k = 0; k < RMAP_EXT; ++k) | |
1729 | if (d->shadow_ptes[k]) | |
1730 | ++nmaps; | |
1731 | else | |
1732 | break; | |
1733 | d = d->more; | |
1734 | } | |
1735 | } | |
1736 | } | |
1737 | return nmaps; | |
1738 | } | |
1739 | ||
1740 | static int count_writable_mappings(struct kvm_vcpu *vcpu) | |
1741 | { | |
1742 | int nmaps = 0; | |
4db35314 | 1743 | struct kvm_mmu_page *sp; |
37a7d8b0 AK |
1744 | int i; |
1745 | ||
f05e70ac | 1746 | list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { |
4db35314 | 1747 | u64 *pt = sp->spt; |
37a7d8b0 | 1748 | |
4db35314 | 1749 | if (sp->role.level != PT_PAGE_TABLE_LEVEL) |
37a7d8b0 AK |
1750 | continue; |
1751 | ||
1752 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { | |
1753 | u64 ent = pt[i]; | |
1754 | ||
1755 | if (!(ent & PT_PRESENT_MASK)) | |
1756 | continue; | |
1757 | if (!(ent & PT_WRITABLE_MASK)) | |
1758 | continue; | |
1759 | ++nmaps; | |
1760 | } | |
1761 | } | |
1762 | return nmaps; | |
1763 | } | |
1764 | ||
1765 | static void audit_rmap(struct kvm_vcpu *vcpu) | |
1766 | { | |
1767 | int n_rmap = count_rmaps(vcpu); | |
1768 | int n_actual = count_writable_mappings(vcpu); | |
1769 | ||
1770 | if (n_rmap != n_actual) | |
1771 | printk(KERN_ERR "%s: (%s) rmap %d actual %d\n", | |
1772 | __FUNCTION__, audit_msg, n_rmap, n_actual); | |
1773 | } | |
1774 | ||
1775 | static void audit_write_protection(struct kvm_vcpu *vcpu) | |
1776 | { | |
4db35314 | 1777 | struct kvm_mmu_page *sp; |
290fc38d IE |
1778 | struct kvm_memory_slot *slot; |
1779 | unsigned long *rmapp; | |
1780 | gfn_t gfn; | |
37a7d8b0 | 1781 | |
f05e70ac | 1782 | list_for_each_entry(sp, &vcpu->kvm->arch.active_mmu_pages, link) { |
4db35314 | 1783 | if (sp->role.metaphysical) |
37a7d8b0 AK |
1784 | continue; |
1785 | ||
4db35314 AK |
1786 | slot = gfn_to_memslot(vcpu->kvm, sp->gfn); |
1787 | gfn = unalias_gfn(vcpu->kvm, sp->gfn); | |
290fc38d IE |
1788 | rmapp = &slot->rmap[gfn - slot->base_gfn]; |
1789 | if (*rmapp) | |
37a7d8b0 AK |
1790 | printk(KERN_ERR "%s: (%s) shadow page has writable" |
1791 | " mappings: gfn %lx role %x\n", | |
4db35314 AK |
1792 | __FUNCTION__, audit_msg, sp->gfn, |
1793 | sp->role.word); | |
37a7d8b0 AK |
1794 | } |
1795 | } | |
1796 | ||
1797 | static void kvm_mmu_audit(struct kvm_vcpu *vcpu, const char *msg) | |
1798 | { | |
1799 | int olddbg = dbg; | |
1800 | ||
1801 | dbg = 0; | |
1802 | audit_msg = msg; | |
1803 | audit_rmap(vcpu); | |
1804 | audit_write_protection(vcpu); | |
1805 | audit_mappings(vcpu); | |
1806 | dbg = olddbg; | |
1807 | } | |
1808 | ||
1809 | #endif |