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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. | |
9611c187 | 10 | * Copyright 2010 Red Hat, Inc. and/or its affiliates. |
6aa8b732 AK |
11 | * |
12 | * Authors: | |
13 | * Yaniv Kamay <yaniv@qumranet.com> | |
14 | * Avi Kivity <avi@qumranet.com> | |
15 | * | |
16 | * This work is licensed under the terms of the GNU GPL, version 2. See | |
17 | * the COPYING file in the top-level directory. | |
18 | * | |
19 | */ | |
e495606d | 20 | |
af585b92 | 21 | #include "irq.h" |
1d737c8a | 22 | #include "mmu.h" |
836a1b3c | 23 | #include "x86.h" |
6de4f3ad | 24 | #include "kvm_cache_regs.h" |
e495606d | 25 | |
edf88417 | 26 | #include <linux/kvm_host.h> |
6aa8b732 AK |
27 | #include <linux/types.h> |
28 | #include <linux/string.h> | |
6aa8b732 AK |
29 | #include <linux/mm.h> |
30 | #include <linux/highmem.h> | |
31 | #include <linux/module.h> | |
448353ca | 32 | #include <linux/swap.h> |
05da4558 | 33 | #include <linux/hugetlb.h> |
2f333bcb | 34 | #include <linux/compiler.h> |
bc6678a3 | 35 | #include <linux/srcu.h> |
5a0e3ad6 | 36 | #include <linux/slab.h> |
bf998156 | 37 | #include <linux/uaccess.h> |
6aa8b732 | 38 | |
e495606d AK |
39 | #include <asm/page.h> |
40 | #include <asm/cmpxchg.h> | |
4e542370 | 41 | #include <asm/io.h> |
13673a90 | 42 | #include <asm/vmx.h> |
6aa8b732 | 43 | |
18552672 JR |
44 | /* |
45 | * When setting this variable to true it enables Two-Dimensional-Paging | |
46 | * where the hardware walks 2 page tables: | |
47 | * 1. the guest-virtual to guest-physical | |
48 | * 2. while doing 1. it walks guest-physical to host-physical | |
49 | * If the hardware supports that we don't need to do shadow paging. | |
50 | */ | |
2f333bcb | 51 | bool tdp_enabled = false; |
18552672 | 52 | |
8b1fe17c XG |
53 | enum { |
54 | AUDIT_PRE_PAGE_FAULT, | |
55 | AUDIT_POST_PAGE_FAULT, | |
56 | AUDIT_PRE_PTE_WRITE, | |
6903074c XG |
57 | AUDIT_POST_PTE_WRITE, |
58 | AUDIT_PRE_SYNC, | |
59 | AUDIT_POST_SYNC | |
8b1fe17c | 60 | }; |
37a7d8b0 | 61 | |
8b1fe17c | 62 | #undef MMU_DEBUG |
37a7d8b0 AK |
63 | |
64 | #ifdef MMU_DEBUG | |
65 | ||
66 | #define pgprintk(x...) do { if (dbg) printk(x); } while (0) | |
67 | #define rmap_printk(x...) do { if (dbg) printk(x); } while (0) | |
68 | ||
69 | #else | |
70 | ||
71 | #define pgprintk(x...) do { } while (0) | |
72 | #define rmap_printk(x...) do { } while (0) | |
73 | ||
74 | #endif | |
75 | ||
8b1fe17c | 76 | #ifdef MMU_DEBUG |
476bc001 | 77 | static bool dbg = 0; |
6ada8cca | 78 | module_param(dbg, bool, 0644); |
37a7d8b0 | 79 | #endif |
6aa8b732 | 80 | |
d6c69ee9 YD |
81 | #ifndef MMU_DEBUG |
82 | #define ASSERT(x) do { } while (0) | |
83 | #else | |
6aa8b732 AK |
84 | #define ASSERT(x) \ |
85 | if (!(x)) { \ | |
86 | printk(KERN_WARNING "assertion failed %s:%d: %s\n", \ | |
87 | __FILE__, __LINE__, #x); \ | |
88 | } | |
d6c69ee9 | 89 | #endif |
6aa8b732 | 90 | |
957ed9ef XG |
91 | #define PTE_PREFETCH_NUM 8 |
92 | ||
00763e41 | 93 | #define PT_FIRST_AVAIL_BITS_SHIFT 10 |
6aa8b732 AK |
94 | #define PT64_SECOND_AVAIL_BITS_SHIFT 52 |
95 | ||
6aa8b732 AK |
96 | #define PT64_LEVEL_BITS 9 |
97 | ||
98 | #define PT64_LEVEL_SHIFT(level) \ | |
d77c26fc | 99 | (PAGE_SHIFT + (level - 1) * PT64_LEVEL_BITS) |
6aa8b732 | 100 | |
6aa8b732 AK |
101 | #define PT64_INDEX(address, level)\ |
102 | (((address) >> PT64_LEVEL_SHIFT(level)) & ((1 << PT64_LEVEL_BITS) - 1)) | |
103 | ||
104 | ||
105 | #define PT32_LEVEL_BITS 10 | |
106 | ||
107 | #define PT32_LEVEL_SHIFT(level) \ | |
d77c26fc | 108 | (PAGE_SHIFT + (level - 1) * PT32_LEVEL_BITS) |
6aa8b732 | 109 | |
e04da980 JR |
110 | #define PT32_LVL_OFFSET_MASK(level) \ |
111 | (PT32_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \ | |
112 | * PT32_LEVEL_BITS))) - 1)) | |
6aa8b732 AK |
113 | |
114 | #define PT32_INDEX(address, level)\ | |
115 | (((address) >> PT32_LEVEL_SHIFT(level)) & ((1 << PT32_LEVEL_BITS) - 1)) | |
116 | ||
117 | ||
27aba766 | 118 | #define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1)) |
6aa8b732 AK |
119 | #define PT64_DIR_BASE_ADDR_MASK \ |
120 | (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + PT64_LEVEL_BITS)) - 1)) | |
e04da980 JR |
121 | #define PT64_LVL_ADDR_MASK(level) \ |
122 | (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \ | |
123 | * PT64_LEVEL_BITS))) - 1)) | |
124 | #define PT64_LVL_OFFSET_MASK(level) \ | |
125 | (PT64_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \ | |
126 | * PT64_LEVEL_BITS))) - 1)) | |
6aa8b732 AK |
127 | |
128 | #define PT32_BASE_ADDR_MASK PAGE_MASK | |
129 | #define PT32_DIR_BASE_ADDR_MASK \ | |
130 | (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + PT32_LEVEL_BITS)) - 1)) | |
e04da980 JR |
131 | #define PT32_LVL_ADDR_MASK(level) \ |
132 | (PAGE_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \ | |
133 | * PT32_LEVEL_BITS))) - 1)) | |
6aa8b732 | 134 | |
79539cec AK |
135 | #define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | PT_USER_MASK \ |
136 | | PT64_NX_MASK) | |
6aa8b732 | 137 | |
fe135d2c AK |
138 | #define ACC_EXEC_MASK 1 |
139 | #define ACC_WRITE_MASK PT_WRITABLE_MASK | |
140 | #define ACC_USER_MASK PT_USER_MASK | |
141 | #define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK) | |
142 | ||
90bb6fc5 AK |
143 | #include <trace/events/kvm.h> |
144 | ||
07420171 AK |
145 | #define CREATE_TRACE_POINTS |
146 | #include "mmutrace.h" | |
147 | ||
49fde340 XG |
148 | #define SPTE_HOST_WRITEABLE (1ULL << PT_FIRST_AVAIL_BITS_SHIFT) |
149 | #define SPTE_MMU_WRITEABLE (1ULL << (PT_FIRST_AVAIL_BITS_SHIFT + 1)) | |
1403283a | 150 | |
135f8c2b AK |
151 | #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level) |
152 | ||
220f773a TY |
153 | /* make pte_list_desc fit well in cache line */ |
154 | #define PTE_LIST_EXT 3 | |
155 | ||
53c07b18 XG |
156 | struct pte_list_desc { |
157 | u64 *sptes[PTE_LIST_EXT]; | |
158 | struct pte_list_desc *more; | |
cd4a4e53 AK |
159 | }; |
160 | ||
2d11123a AK |
161 | struct kvm_shadow_walk_iterator { |
162 | u64 addr; | |
163 | hpa_t shadow_addr; | |
2d11123a | 164 | u64 *sptep; |
dd3bfd59 | 165 | int level; |
2d11123a AK |
166 | unsigned index; |
167 | }; | |
168 | ||
169 | #define for_each_shadow_entry(_vcpu, _addr, _walker) \ | |
170 | for (shadow_walk_init(&(_walker), _vcpu, _addr); \ | |
171 | shadow_walk_okay(&(_walker)); \ | |
172 | shadow_walk_next(&(_walker))) | |
173 | ||
c2a2ac2b XG |
174 | #define for_each_shadow_entry_lockless(_vcpu, _addr, _walker, spte) \ |
175 | for (shadow_walk_init(&(_walker), _vcpu, _addr); \ | |
176 | shadow_walk_okay(&(_walker)) && \ | |
177 | ({ spte = mmu_spte_get_lockless(_walker.sptep); 1; }); \ | |
178 | __shadow_walk_next(&(_walker), spte)) | |
179 | ||
53c07b18 | 180 | static struct kmem_cache *pte_list_desc_cache; |
d3d25b04 | 181 | static struct kmem_cache *mmu_page_header_cache; |
45221ab6 | 182 | static struct percpu_counter kvm_total_used_mmu_pages; |
b5a33a75 | 183 | |
7b52345e SY |
184 | static u64 __read_mostly shadow_nx_mask; |
185 | static u64 __read_mostly shadow_x_mask; /* mutual exclusive with nx_mask */ | |
186 | static u64 __read_mostly shadow_user_mask; | |
187 | static u64 __read_mostly shadow_accessed_mask; | |
188 | static u64 __read_mostly shadow_dirty_mask; | |
ce88decf XG |
189 | static u64 __read_mostly shadow_mmio_mask; |
190 | ||
191 | static void mmu_spte_set(u64 *sptep, u64 spte); | |
e676505a | 192 | static void mmu_free_roots(struct kvm_vcpu *vcpu); |
ce88decf XG |
193 | |
194 | void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask) | |
195 | { | |
196 | shadow_mmio_mask = mmio_mask; | |
197 | } | |
198 | EXPORT_SYMBOL_GPL(kvm_mmu_set_mmio_spte_mask); | |
199 | ||
200 | static void mark_mmio_spte(u64 *sptep, u64 gfn, unsigned access) | |
201 | { | |
202 | access &= ACC_WRITE_MASK | ACC_USER_MASK; | |
203 | ||
4f022648 | 204 | trace_mark_mmio_spte(sptep, gfn, access); |
ce88decf XG |
205 | mmu_spte_set(sptep, shadow_mmio_mask | access | gfn << PAGE_SHIFT); |
206 | } | |
207 | ||
208 | static bool is_mmio_spte(u64 spte) | |
209 | { | |
210 | return (spte & shadow_mmio_mask) == shadow_mmio_mask; | |
211 | } | |
212 | ||
213 | static gfn_t get_mmio_spte_gfn(u64 spte) | |
214 | { | |
215 | return (spte & ~shadow_mmio_mask) >> PAGE_SHIFT; | |
216 | } | |
217 | ||
218 | static unsigned get_mmio_spte_access(u64 spte) | |
219 | { | |
220 | return (spte & ~shadow_mmio_mask) & ~PAGE_MASK; | |
221 | } | |
222 | ||
223 | static bool set_mmio_spte(u64 *sptep, gfn_t gfn, pfn_t pfn, unsigned access) | |
224 | { | |
225 | if (unlikely(is_noslot_pfn(pfn))) { | |
226 | mark_mmio_spte(sptep, gfn, access); | |
227 | return true; | |
228 | } | |
229 | ||
230 | return false; | |
231 | } | |
c7addb90 | 232 | |
82725b20 DE |
233 | static inline u64 rsvd_bits(int s, int e) |
234 | { | |
235 | return ((1ULL << (e - s + 1)) - 1) << s; | |
236 | } | |
237 | ||
7b52345e | 238 | void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, |
4b12f0de | 239 | u64 dirty_mask, u64 nx_mask, u64 x_mask) |
7b52345e SY |
240 | { |
241 | shadow_user_mask = user_mask; | |
242 | shadow_accessed_mask = accessed_mask; | |
243 | shadow_dirty_mask = dirty_mask; | |
244 | shadow_nx_mask = nx_mask; | |
245 | shadow_x_mask = x_mask; | |
246 | } | |
247 | EXPORT_SYMBOL_GPL(kvm_mmu_set_mask_ptes); | |
248 | ||
6aa8b732 AK |
249 | static int is_cpuid_PSE36(void) |
250 | { | |
251 | return 1; | |
252 | } | |
253 | ||
73b1087e AK |
254 | static int is_nx(struct kvm_vcpu *vcpu) |
255 | { | |
f6801dff | 256 | return vcpu->arch.efer & EFER_NX; |
73b1087e AK |
257 | } |
258 | ||
c7addb90 AK |
259 | static int is_shadow_present_pte(u64 pte) |
260 | { | |
ce88decf | 261 | return pte & PT_PRESENT_MASK && !is_mmio_spte(pte); |
c7addb90 AK |
262 | } |
263 | ||
05da4558 MT |
264 | static int is_large_pte(u64 pte) |
265 | { | |
266 | return pte & PT_PAGE_SIZE_MASK; | |
267 | } | |
268 | ||
43a3795a | 269 | static int is_dirty_gpte(unsigned long pte) |
e3c5e7ec | 270 | { |
439e218a | 271 | return pte & PT_DIRTY_MASK; |
e3c5e7ec AK |
272 | } |
273 | ||
43a3795a | 274 | static int is_rmap_spte(u64 pte) |
cd4a4e53 | 275 | { |
4b1a80fa | 276 | return is_shadow_present_pte(pte); |
cd4a4e53 AK |
277 | } |
278 | ||
776e6633 MT |
279 | static int is_last_spte(u64 pte, int level) |
280 | { | |
281 | if (level == PT_PAGE_TABLE_LEVEL) | |
282 | return 1; | |
852e3c19 | 283 | if (is_large_pte(pte)) |
776e6633 MT |
284 | return 1; |
285 | return 0; | |
286 | } | |
287 | ||
35149e21 | 288 | static pfn_t spte_to_pfn(u64 pte) |
0b49ea86 | 289 | { |
35149e21 | 290 | return (pte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT; |
0b49ea86 AK |
291 | } |
292 | ||
da928521 AK |
293 | static gfn_t pse36_gfn_delta(u32 gpte) |
294 | { | |
295 | int shift = 32 - PT32_DIR_PSE36_SHIFT - PAGE_SHIFT; | |
296 | ||
297 | return (gpte & PT32_DIR_PSE36_MASK) << shift; | |
298 | } | |
299 | ||
603e0651 | 300 | #ifdef CONFIG_X86_64 |
d555c333 | 301 | static void __set_spte(u64 *sptep, u64 spte) |
e663ee64 | 302 | { |
603e0651 | 303 | *sptep = spte; |
e663ee64 AK |
304 | } |
305 | ||
603e0651 | 306 | static void __update_clear_spte_fast(u64 *sptep, u64 spte) |
a9221dd5 | 307 | { |
603e0651 XG |
308 | *sptep = spte; |
309 | } | |
310 | ||
311 | static u64 __update_clear_spte_slow(u64 *sptep, u64 spte) | |
312 | { | |
313 | return xchg(sptep, spte); | |
314 | } | |
c2a2ac2b XG |
315 | |
316 | static u64 __get_spte_lockless(u64 *sptep) | |
317 | { | |
318 | return ACCESS_ONCE(*sptep); | |
319 | } | |
ce88decf XG |
320 | |
321 | static bool __check_direct_spte_mmio_pf(u64 spte) | |
322 | { | |
323 | /* It is valid if the spte is zapped. */ | |
324 | return spte == 0ull; | |
325 | } | |
a9221dd5 | 326 | #else |
603e0651 XG |
327 | union split_spte { |
328 | struct { | |
329 | u32 spte_low; | |
330 | u32 spte_high; | |
331 | }; | |
332 | u64 spte; | |
333 | }; | |
a9221dd5 | 334 | |
c2a2ac2b XG |
335 | static void count_spte_clear(u64 *sptep, u64 spte) |
336 | { | |
337 | struct kvm_mmu_page *sp = page_header(__pa(sptep)); | |
338 | ||
339 | if (is_shadow_present_pte(spte)) | |
340 | return; | |
341 | ||
342 | /* Ensure the spte is completely set before we increase the count */ | |
343 | smp_wmb(); | |
344 | sp->clear_spte_count++; | |
345 | } | |
346 | ||
603e0651 XG |
347 | static void __set_spte(u64 *sptep, u64 spte) |
348 | { | |
349 | union split_spte *ssptep, sspte; | |
a9221dd5 | 350 | |
603e0651 XG |
351 | ssptep = (union split_spte *)sptep; |
352 | sspte = (union split_spte)spte; | |
353 | ||
354 | ssptep->spte_high = sspte.spte_high; | |
355 | ||
356 | /* | |
357 | * If we map the spte from nonpresent to present, We should store | |
358 | * the high bits firstly, then set present bit, so cpu can not | |
359 | * fetch this spte while we are setting the spte. | |
360 | */ | |
361 | smp_wmb(); | |
362 | ||
363 | ssptep->spte_low = sspte.spte_low; | |
a9221dd5 AK |
364 | } |
365 | ||
603e0651 XG |
366 | static void __update_clear_spte_fast(u64 *sptep, u64 spte) |
367 | { | |
368 | union split_spte *ssptep, sspte; | |
369 | ||
370 | ssptep = (union split_spte *)sptep; | |
371 | sspte = (union split_spte)spte; | |
372 | ||
373 | ssptep->spte_low = sspte.spte_low; | |
374 | ||
375 | /* | |
376 | * If we map the spte from present to nonpresent, we should clear | |
377 | * present bit firstly to avoid vcpu fetch the old high bits. | |
378 | */ | |
379 | smp_wmb(); | |
380 | ||
381 | ssptep->spte_high = sspte.spte_high; | |
c2a2ac2b | 382 | count_spte_clear(sptep, spte); |
603e0651 XG |
383 | } |
384 | ||
385 | static u64 __update_clear_spte_slow(u64 *sptep, u64 spte) | |
386 | { | |
387 | union split_spte *ssptep, sspte, orig; | |
388 | ||
389 | ssptep = (union split_spte *)sptep; | |
390 | sspte = (union split_spte)spte; | |
391 | ||
392 | /* xchg acts as a barrier before the setting of the high bits */ | |
393 | orig.spte_low = xchg(&ssptep->spte_low, sspte.spte_low); | |
41bc3186 ZJ |
394 | orig.spte_high = ssptep->spte_high; |
395 | ssptep->spte_high = sspte.spte_high; | |
c2a2ac2b | 396 | count_spte_clear(sptep, spte); |
603e0651 XG |
397 | |
398 | return orig.spte; | |
399 | } | |
c2a2ac2b XG |
400 | |
401 | /* | |
402 | * The idea using the light way get the spte on x86_32 guest is from | |
403 | * gup_get_pte(arch/x86/mm/gup.c). | |
404 | * The difference is we can not catch the spte tlb flush if we leave | |
405 | * guest mode, so we emulate it by increase clear_spte_count when spte | |
406 | * is cleared. | |
407 | */ | |
408 | static u64 __get_spte_lockless(u64 *sptep) | |
409 | { | |
410 | struct kvm_mmu_page *sp = page_header(__pa(sptep)); | |
411 | union split_spte spte, *orig = (union split_spte *)sptep; | |
412 | int count; | |
413 | ||
414 | retry: | |
415 | count = sp->clear_spte_count; | |
416 | smp_rmb(); | |
417 | ||
418 | spte.spte_low = orig->spte_low; | |
419 | smp_rmb(); | |
420 | ||
421 | spte.spte_high = orig->spte_high; | |
422 | smp_rmb(); | |
423 | ||
424 | if (unlikely(spte.spte_low != orig->spte_low || | |
425 | count != sp->clear_spte_count)) | |
426 | goto retry; | |
427 | ||
428 | return spte.spte; | |
429 | } | |
ce88decf XG |
430 | |
431 | static bool __check_direct_spte_mmio_pf(u64 spte) | |
432 | { | |
433 | union split_spte sspte = (union split_spte)spte; | |
434 | u32 high_mmio_mask = shadow_mmio_mask >> 32; | |
435 | ||
436 | /* It is valid if the spte is zapped. */ | |
437 | if (spte == 0ull) | |
438 | return true; | |
439 | ||
440 | /* It is valid if the spte is being zapped. */ | |
441 | if (sspte.spte_low == 0ull && | |
442 | (sspte.spte_high & high_mmio_mask) == high_mmio_mask) | |
443 | return true; | |
444 | ||
445 | return false; | |
446 | } | |
603e0651 XG |
447 | #endif |
448 | ||
c7ba5b48 XG |
449 | static bool spte_is_locklessly_modifiable(u64 spte) |
450 | { | |
451 | return !(~spte & (SPTE_HOST_WRITEABLE | SPTE_MMU_WRITEABLE)); | |
452 | } | |
453 | ||
8672b721 XG |
454 | static bool spte_has_volatile_bits(u64 spte) |
455 | { | |
c7ba5b48 XG |
456 | /* |
457 | * Always atomicly update spte if it can be updated | |
458 | * out of mmu-lock, it can ensure dirty bit is not lost, | |
459 | * also, it can help us to get a stable is_writable_pte() | |
460 | * to ensure tlb flush is not missed. | |
461 | */ | |
462 | if (spte_is_locklessly_modifiable(spte)) | |
463 | return true; | |
464 | ||
8672b721 XG |
465 | if (!shadow_accessed_mask) |
466 | return false; | |
467 | ||
468 | if (!is_shadow_present_pte(spte)) | |
469 | return false; | |
470 | ||
4132779b XG |
471 | if ((spte & shadow_accessed_mask) && |
472 | (!is_writable_pte(spte) || (spte & shadow_dirty_mask))) | |
8672b721 XG |
473 | return false; |
474 | ||
475 | return true; | |
476 | } | |
477 | ||
4132779b XG |
478 | static bool spte_is_bit_cleared(u64 old_spte, u64 new_spte, u64 bit_mask) |
479 | { | |
480 | return (old_spte & bit_mask) && !(new_spte & bit_mask); | |
481 | } | |
482 | ||
1df9f2dc XG |
483 | /* Rules for using mmu_spte_set: |
484 | * Set the sptep from nonpresent to present. | |
485 | * Note: the sptep being assigned *must* be either not present | |
486 | * or in a state where the hardware will not attempt to update | |
487 | * the spte. | |
488 | */ | |
489 | static void mmu_spte_set(u64 *sptep, u64 new_spte) | |
490 | { | |
491 | WARN_ON(is_shadow_present_pte(*sptep)); | |
492 | __set_spte(sptep, new_spte); | |
493 | } | |
494 | ||
495 | /* Rules for using mmu_spte_update: | |
496 | * Update the state bits, it means the mapped pfn is not changged. | |
6e7d0354 XG |
497 | * |
498 | * Whenever we overwrite a writable spte with a read-only one we | |
499 | * should flush remote TLBs. Otherwise rmap_write_protect | |
500 | * will find a read-only spte, even though the writable spte | |
501 | * might be cached on a CPU's TLB, the return value indicates this | |
502 | * case. | |
1df9f2dc | 503 | */ |
6e7d0354 | 504 | static bool mmu_spte_update(u64 *sptep, u64 new_spte) |
b79b93f9 | 505 | { |
c7ba5b48 | 506 | u64 old_spte = *sptep; |
6e7d0354 | 507 | bool ret = false; |
4132779b XG |
508 | |
509 | WARN_ON(!is_rmap_spte(new_spte)); | |
b79b93f9 | 510 | |
6e7d0354 XG |
511 | if (!is_shadow_present_pte(old_spte)) { |
512 | mmu_spte_set(sptep, new_spte); | |
513 | return ret; | |
514 | } | |
1df9f2dc | 515 | |
c7ba5b48 | 516 | if (!spte_has_volatile_bits(old_spte)) |
603e0651 | 517 | __update_clear_spte_fast(sptep, new_spte); |
4132779b | 518 | else |
603e0651 | 519 | old_spte = __update_clear_spte_slow(sptep, new_spte); |
4132779b | 520 | |
c7ba5b48 XG |
521 | /* |
522 | * For the spte updated out of mmu-lock is safe, since | |
523 | * we always atomicly update it, see the comments in | |
524 | * spte_has_volatile_bits(). | |
525 | */ | |
6e7d0354 XG |
526 | if (is_writable_pte(old_spte) && !is_writable_pte(new_spte)) |
527 | ret = true; | |
528 | ||
4132779b | 529 | if (!shadow_accessed_mask) |
6e7d0354 | 530 | return ret; |
4132779b XG |
531 | |
532 | if (spte_is_bit_cleared(old_spte, new_spte, shadow_accessed_mask)) | |
533 | kvm_set_pfn_accessed(spte_to_pfn(old_spte)); | |
534 | if (spte_is_bit_cleared(old_spte, new_spte, shadow_dirty_mask)) | |
535 | kvm_set_pfn_dirty(spte_to_pfn(old_spte)); | |
6e7d0354 XG |
536 | |
537 | return ret; | |
b79b93f9 AK |
538 | } |
539 | ||
1df9f2dc XG |
540 | /* |
541 | * Rules for using mmu_spte_clear_track_bits: | |
542 | * It sets the sptep from present to nonpresent, and track the | |
543 | * state bits, it is used to clear the last level sptep. | |
544 | */ | |
545 | static int mmu_spte_clear_track_bits(u64 *sptep) | |
546 | { | |
547 | pfn_t pfn; | |
548 | u64 old_spte = *sptep; | |
549 | ||
550 | if (!spte_has_volatile_bits(old_spte)) | |
603e0651 | 551 | __update_clear_spte_fast(sptep, 0ull); |
1df9f2dc | 552 | else |
603e0651 | 553 | old_spte = __update_clear_spte_slow(sptep, 0ull); |
1df9f2dc XG |
554 | |
555 | if (!is_rmap_spte(old_spte)) | |
556 | return 0; | |
557 | ||
558 | pfn = spte_to_pfn(old_spte); | |
86fde74c XG |
559 | |
560 | /* | |
561 | * KVM does not hold the refcount of the page used by | |
562 | * kvm mmu, before reclaiming the page, we should | |
563 | * unmap it from mmu first. | |
564 | */ | |
565 | WARN_ON(!kvm_is_mmio_pfn(pfn) && !page_count(pfn_to_page(pfn))); | |
566 | ||
1df9f2dc XG |
567 | if (!shadow_accessed_mask || old_spte & shadow_accessed_mask) |
568 | kvm_set_pfn_accessed(pfn); | |
569 | if (!shadow_dirty_mask || (old_spte & shadow_dirty_mask)) | |
570 | kvm_set_pfn_dirty(pfn); | |
571 | return 1; | |
572 | } | |
573 | ||
574 | /* | |
575 | * Rules for using mmu_spte_clear_no_track: | |
576 | * Directly clear spte without caring the state bits of sptep, | |
577 | * it is used to set the upper level spte. | |
578 | */ | |
579 | static void mmu_spte_clear_no_track(u64 *sptep) | |
580 | { | |
603e0651 | 581 | __update_clear_spte_fast(sptep, 0ull); |
1df9f2dc XG |
582 | } |
583 | ||
c2a2ac2b XG |
584 | static u64 mmu_spte_get_lockless(u64 *sptep) |
585 | { | |
586 | return __get_spte_lockless(sptep); | |
587 | } | |
588 | ||
589 | static void walk_shadow_page_lockless_begin(struct kvm_vcpu *vcpu) | |
590 | { | |
c142786c AK |
591 | /* |
592 | * Prevent page table teardown by making any free-er wait during | |
593 | * kvm_flush_remote_tlbs() IPI to all active vcpus. | |
594 | */ | |
595 | local_irq_disable(); | |
596 | vcpu->mode = READING_SHADOW_PAGE_TABLES; | |
597 | /* | |
598 | * Make sure a following spte read is not reordered ahead of the write | |
599 | * to vcpu->mode. | |
600 | */ | |
601 | smp_mb(); | |
c2a2ac2b XG |
602 | } |
603 | ||
604 | static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu) | |
605 | { | |
c142786c AK |
606 | /* |
607 | * Make sure the write to vcpu->mode is not reordered in front of | |
608 | * reads to sptes. If it does, kvm_commit_zap_page() can see us | |
609 | * OUTSIDE_GUEST_MODE and proceed to free the shadow page table. | |
610 | */ | |
611 | smp_mb(); | |
612 | vcpu->mode = OUTSIDE_GUEST_MODE; | |
613 | local_irq_enable(); | |
c2a2ac2b XG |
614 | } |
615 | ||
e2dec939 | 616 | static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache, |
2e3e5882 | 617 | struct kmem_cache *base_cache, int min) |
714b93da AK |
618 | { |
619 | void *obj; | |
620 | ||
621 | if (cache->nobjs >= min) | |
e2dec939 | 622 | return 0; |
714b93da | 623 | while (cache->nobjs < ARRAY_SIZE(cache->objects)) { |
2e3e5882 | 624 | obj = kmem_cache_zalloc(base_cache, GFP_KERNEL); |
714b93da | 625 | if (!obj) |
e2dec939 | 626 | return -ENOMEM; |
714b93da AK |
627 | cache->objects[cache->nobjs++] = obj; |
628 | } | |
e2dec939 | 629 | return 0; |
714b93da AK |
630 | } |
631 | ||
f759e2b4 XG |
632 | static int mmu_memory_cache_free_objects(struct kvm_mmu_memory_cache *cache) |
633 | { | |
634 | return cache->nobjs; | |
635 | } | |
636 | ||
e8ad9a70 XG |
637 | static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc, |
638 | struct kmem_cache *cache) | |
714b93da AK |
639 | { |
640 | while (mc->nobjs) | |
e8ad9a70 | 641 | kmem_cache_free(cache, mc->objects[--mc->nobjs]); |
714b93da AK |
642 | } |
643 | ||
c1158e63 | 644 | static int mmu_topup_memory_cache_page(struct kvm_mmu_memory_cache *cache, |
2e3e5882 | 645 | int min) |
c1158e63 | 646 | { |
842f22ed | 647 | void *page; |
c1158e63 AK |
648 | |
649 | if (cache->nobjs >= min) | |
650 | return 0; | |
651 | while (cache->nobjs < ARRAY_SIZE(cache->objects)) { | |
842f22ed | 652 | page = (void *)__get_free_page(GFP_KERNEL); |
c1158e63 AK |
653 | if (!page) |
654 | return -ENOMEM; | |
842f22ed | 655 | cache->objects[cache->nobjs++] = page; |
c1158e63 AK |
656 | } |
657 | return 0; | |
658 | } | |
659 | ||
660 | static void mmu_free_memory_cache_page(struct kvm_mmu_memory_cache *mc) | |
661 | { | |
662 | while (mc->nobjs) | |
c4d198d5 | 663 | free_page((unsigned long)mc->objects[--mc->nobjs]); |
c1158e63 AK |
664 | } |
665 | ||
2e3e5882 | 666 | static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu) |
714b93da | 667 | { |
e2dec939 AK |
668 | int r; |
669 | ||
53c07b18 | 670 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache, |
67052b35 | 671 | pte_list_desc_cache, 8 + PTE_PREFETCH_NUM); |
d3d25b04 AK |
672 | if (r) |
673 | goto out; | |
ad312c7c | 674 | r = mmu_topup_memory_cache_page(&vcpu->arch.mmu_page_cache, 8); |
d3d25b04 AK |
675 | if (r) |
676 | goto out; | |
ad312c7c | 677 | r = mmu_topup_memory_cache(&vcpu->arch.mmu_page_header_cache, |
2e3e5882 | 678 | mmu_page_header_cache, 4); |
e2dec939 AK |
679 | out: |
680 | return r; | |
714b93da AK |
681 | } |
682 | ||
683 | static void mmu_free_memory_caches(struct kvm_vcpu *vcpu) | |
684 | { | |
53c07b18 XG |
685 | mmu_free_memory_cache(&vcpu->arch.mmu_pte_list_desc_cache, |
686 | pte_list_desc_cache); | |
ad312c7c | 687 | mmu_free_memory_cache_page(&vcpu->arch.mmu_page_cache); |
e8ad9a70 XG |
688 | mmu_free_memory_cache(&vcpu->arch.mmu_page_header_cache, |
689 | mmu_page_header_cache); | |
714b93da AK |
690 | } |
691 | ||
80feb89a | 692 | static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc) |
714b93da AK |
693 | { |
694 | void *p; | |
695 | ||
696 | BUG_ON(!mc->nobjs); | |
697 | p = mc->objects[--mc->nobjs]; | |
714b93da AK |
698 | return p; |
699 | } | |
700 | ||
53c07b18 | 701 | static struct pte_list_desc *mmu_alloc_pte_list_desc(struct kvm_vcpu *vcpu) |
714b93da | 702 | { |
80feb89a | 703 | return mmu_memory_cache_alloc(&vcpu->arch.mmu_pte_list_desc_cache); |
714b93da AK |
704 | } |
705 | ||
53c07b18 | 706 | static void mmu_free_pte_list_desc(struct pte_list_desc *pte_list_desc) |
714b93da | 707 | { |
53c07b18 | 708 | kmem_cache_free(pte_list_desc_cache, pte_list_desc); |
714b93da AK |
709 | } |
710 | ||
2032a93d LJ |
711 | static gfn_t kvm_mmu_page_get_gfn(struct kvm_mmu_page *sp, int index) |
712 | { | |
713 | if (!sp->role.direct) | |
714 | return sp->gfns[index]; | |
715 | ||
716 | return sp->gfn + (index << ((sp->role.level - 1) * PT64_LEVEL_BITS)); | |
717 | } | |
718 | ||
719 | static void kvm_mmu_page_set_gfn(struct kvm_mmu_page *sp, int index, gfn_t gfn) | |
720 | { | |
721 | if (sp->role.direct) | |
722 | BUG_ON(gfn != kvm_mmu_page_get_gfn(sp, index)); | |
723 | else | |
724 | sp->gfns[index] = gfn; | |
725 | } | |
726 | ||
05da4558 | 727 | /* |
d4dbf470 TY |
728 | * Return the pointer to the large page information for a given gfn, |
729 | * handling slots that are not large page aligned. | |
05da4558 | 730 | */ |
d4dbf470 TY |
731 | static struct kvm_lpage_info *lpage_info_slot(gfn_t gfn, |
732 | struct kvm_memory_slot *slot, | |
733 | int level) | |
05da4558 MT |
734 | { |
735 | unsigned long idx; | |
736 | ||
fb03cb6f | 737 | idx = gfn_to_index(gfn, slot->base_gfn, level); |
db3fe4eb | 738 | return &slot->arch.lpage_info[level - 2][idx]; |
05da4558 MT |
739 | } |
740 | ||
741 | static void account_shadowed(struct kvm *kvm, gfn_t gfn) | |
742 | { | |
d25797b2 | 743 | struct kvm_memory_slot *slot; |
d4dbf470 | 744 | struct kvm_lpage_info *linfo; |
d25797b2 | 745 | int i; |
05da4558 | 746 | |
a1f4d395 | 747 | slot = gfn_to_memslot(kvm, gfn); |
d25797b2 JR |
748 | for (i = PT_DIRECTORY_LEVEL; |
749 | i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { | |
d4dbf470 TY |
750 | linfo = lpage_info_slot(gfn, slot, i); |
751 | linfo->write_count += 1; | |
d25797b2 | 752 | } |
332b207d | 753 | kvm->arch.indirect_shadow_pages++; |
05da4558 MT |
754 | } |
755 | ||
756 | static void unaccount_shadowed(struct kvm *kvm, gfn_t gfn) | |
757 | { | |
d25797b2 | 758 | struct kvm_memory_slot *slot; |
d4dbf470 | 759 | struct kvm_lpage_info *linfo; |
d25797b2 | 760 | int i; |
05da4558 | 761 | |
a1f4d395 | 762 | slot = gfn_to_memslot(kvm, gfn); |
d25797b2 JR |
763 | for (i = PT_DIRECTORY_LEVEL; |
764 | i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { | |
d4dbf470 TY |
765 | linfo = lpage_info_slot(gfn, slot, i); |
766 | linfo->write_count -= 1; | |
767 | WARN_ON(linfo->write_count < 0); | |
d25797b2 | 768 | } |
332b207d | 769 | kvm->arch.indirect_shadow_pages--; |
05da4558 MT |
770 | } |
771 | ||
d25797b2 JR |
772 | static int has_wrprotected_page(struct kvm *kvm, |
773 | gfn_t gfn, | |
774 | int level) | |
05da4558 | 775 | { |
2843099f | 776 | struct kvm_memory_slot *slot; |
d4dbf470 | 777 | struct kvm_lpage_info *linfo; |
05da4558 | 778 | |
a1f4d395 | 779 | slot = gfn_to_memslot(kvm, gfn); |
05da4558 | 780 | if (slot) { |
d4dbf470 TY |
781 | linfo = lpage_info_slot(gfn, slot, level); |
782 | return linfo->write_count; | |
05da4558 MT |
783 | } |
784 | ||
785 | return 1; | |
786 | } | |
787 | ||
d25797b2 | 788 | static int host_mapping_level(struct kvm *kvm, gfn_t gfn) |
05da4558 | 789 | { |
8f0b1ab6 | 790 | unsigned long page_size; |
d25797b2 | 791 | int i, ret = 0; |
05da4558 | 792 | |
8f0b1ab6 | 793 | page_size = kvm_host_page_size(kvm, gfn); |
05da4558 | 794 | |
d25797b2 JR |
795 | for (i = PT_PAGE_TABLE_LEVEL; |
796 | i < (PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES); ++i) { | |
797 | if (page_size >= KVM_HPAGE_SIZE(i)) | |
798 | ret = i; | |
799 | else | |
800 | break; | |
801 | } | |
802 | ||
4c2155ce | 803 | return ret; |
05da4558 MT |
804 | } |
805 | ||
5d163b1c XG |
806 | static struct kvm_memory_slot * |
807 | gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn, | |
808 | bool no_dirty_log) | |
05da4558 MT |
809 | { |
810 | struct kvm_memory_slot *slot; | |
5d163b1c XG |
811 | |
812 | slot = gfn_to_memslot(vcpu->kvm, gfn); | |
813 | if (!slot || slot->flags & KVM_MEMSLOT_INVALID || | |
814 | (no_dirty_log && slot->dirty_bitmap)) | |
815 | slot = NULL; | |
816 | ||
817 | return slot; | |
818 | } | |
819 | ||
820 | static bool mapping_level_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t large_gfn) | |
821 | { | |
a0a8eaba | 822 | return !gfn_to_memslot_dirty_bitmap(vcpu, large_gfn, true); |
936a5fe6 AA |
823 | } |
824 | ||
825 | static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn) | |
826 | { | |
827 | int host_level, level, max_level; | |
05da4558 | 828 | |
d25797b2 JR |
829 | host_level = host_mapping_level(vcpu->kvm, large_gfn); |
830 | ||
831 | if (host_level == PT_PAGE_TABLE_LEVEL) | |
832 | return host_level; | |
833 | ||
878403b7 SY |
834 | max_level = kvm_x86_ops->get_lpage_level() < host_level ? |
835 | kvm_x86_ops->get_lpage_level() : host_level; | |
836 | ||
837 | for (level = PT_DIRECTORY_LEVEL; level <= max_level; ++level) | |
d25797b2 JR |
838 | if (has_wrprotected_page(vcpu->kvm, large_gfn, level)) |
839 | break; | |
d25797b2 JR |
840 | |
841 | return level - 1; | |
05da4558 MT |
842 | } |
843 | ||
290fc38d | 844 | /* |
53c07b18 | 845 | * Pte mapping structures: |
cd4a4e53 | 846 | * |
53c07b18 | 847 | * If pte_list bit zero is zero, then pte_list point to the spte. |
cd4a4e53 | 848 | * |
53c07b18 XG |
849 | * If pte_list bit zero is one, (then pte_list & ~1) points to a struct |
850 | * pte_list_desc containing more mappings. | |
53a27b39 | 851 | * |
53c07b18 | 852 | * Returns the number of pte entries before the spte was added or zero if |
53a27b39 MT |
853 | * the spte was not added. |
854 | * | |
cd4a4e53 | 855 | */ |
53c07b18 XG |
856 | static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte, |
857 | unsigned long *pte_list) | |
cd4a4e53 | 858 | { |
53c07b18 | 859 | struct pte_list_desc *desc; |
53a27b39 | 860 | int i, count = 0; |
cd4a4e53 | 861 | |
53c07b18 XG |
862 | if (!*pte_list) { |
863 | rmap_printk("pte_list_add: %p %llx 0->1\n", spte, *spte); | |
864 | *pte_list = (unsigned long)spte; | |
865 | } else if (!(*pte_list & 1)) { | |
866 | rmap_printk("pte_list_add: %p %llx 1->many\n", spte, *spte); | |
867 | desc = mmu_alloc_pte_list_desc(vcpu); | |
868 | desc->sptes[0] = (u64 *)*pte_list; | |
d555c333 | 869 | desc->sptes[1] = spte; |
53c07b18 | 870 | *pte_list = (unsigned long)desc | 1; |
cb16a7b3 | 871 | ++count; |
cd4a4e53 | 872 | } else { |
53c07b18 XG |
873 | rmap_printk("pte_list_add: %p %llx many->many\n", spte, *spte); |
874 | desc = (struct pte_list_desc *)(*pte_list & ~1ul); | |
875 | while (desc->sptes[PTE_LIST_EXT-1] && desc->more) { | |
cd4a4e53 | 876 | desc = desc->more; |
53c07b18 | 877 | count += PTE_LIST_EXT; |
53a27b39 | 878 | } |
53c07b18 XG |
879 | if (desc->sptes[PTE_LIST_EXT-1]) { |
880 | desc->more = mmu_alloc_pte_list_desc(vcpu); | |
cd4a4e53 AK |
881 | desc = desc->more; |
882 | } | |
d555c333 | 883 | for (i = 0; desc->sptes[i]; ++i) |
cb16a7b3 | 884 | ++count; |
d555c333 | 885 | desc->sptes[i] = spte; |
cd4a4e53 | 886 | } |
53a27b39 | 887 | return count; |
cd4a4e53 AK |
888 | } |
889 | ||
53c07b18 XG |
890 | static void |
891 | pte_list_desc_remove_entry(unsigned long *pte_list, struct pte_list_desc *desc, | |
892 | int i, struct pte_list_desc *prev_desc) | |
cd4a4e53 AK |
893 | { |
894 | int j; | |
895 | ||
53c07b18 | 896 | for (j = PTE_LIST_EXT - 1; !desc->sptes[j] && j > i; --j) |
cd4a4e53 | 897 | ; |
d555c333 AK |
898 | desc->sptes[i] = desc->sptes[j]; |
899 | desc->sptes[j] = NULL; | |
cd4a4e53 AK |
900 | if (j != 0) |
901 | return; | |
902 | if (!prev_desc && !desc->more) | |
53c07b18 | 903 | *pte_list = (unsigned long)desc->sptes[0]; |
cd4a4e53 AK |
904 | else |
905 | if (prev_desc) | |
906 | prev_desc->more = desc->more; | |
907 | else | |
53c07b18 XG |
908 | *pte_list = (unsigned long)desc->more | 1; |
909 | mmu_free_pte_list_desc(desc); | |
cd4a4e53 AK |
910 | } |
911 | ||
53c07b18 | 912 | static void pte_list_remove(u64 *spte, unsigned long *pte_list) |
cd4a4e53 | 913 | { |
53c07b18 XG |
914 | struct pte_list_desc *desc; |
915 | struct pte_list_desc *prev_desc; | |
cd4a4e53 AK |
916 | int i; |
917 | ||
53c07b18 XG |
918 | if (!*pte_list) { |
919 | printk(KERN_ERR "pte_list_remove: %p 0->BUG\n", spte); | |
cd4a4e53 | 920 | BUG(); |
53c07b18 XG |
921 | } else if (!(*pte_list & 1)) { |
922 | rmap_printk("pte_list_remove: %p 1->0\n", spte); | |
923 | if ((u64 *)*pte_list != spte) { | |
924 | printk(KERN_ERR "pte_list_remove: %p 1->BUG\n", spte); | |
cd4a4e53 AK |
925 | BUG(); |
926 | } | |
53c07b18 | 927 | *pte_list = 0; |
cd4a4e53 | 928 | } else { |
53c07b18 XG |
929 | rmap_printk("pte_list_remove: %p many->many\n", spte); |
930 | desc = (struct pte_list_desc *)(*pte_list & ~1ul); | |
cd4a4e53 AK |
931 | prev_desc = NULL; |
932 | while (desc) { | |
53c07b18 | 933 | for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i) |
d555c333 | 934 | if (desc->sptes[i] == spte) { |
53c07b18 | 935 | pte_list_desc_remove_entry(pte_list, |
714b93da | 936 | desc, i, |
cd4a4e53 AK |
937 | prev_desc); |
938 | return; | |
939 | } | |
940 | prev_desc = desc; | |
941 | desc = desc->more; | |
942 | } | |
53c07b18 | 943 | pr_err("pte_list_remove: %p many->many\n", spte); |
cd4a4e53 AK |
944 | BUG(); |
945 | } | |
946 | } | |
947 | ||
67052b35 XG |
948 | typedef void (*pte_list_walk_fn) (u64 *spte); |
949 | static void pte_list_walk(unsigned long *pte_list, pte_list_walk_fn fn) | |
950 | { | |
951 | struct pte_list_desc *desc; | |
952 | int i; | |
953 | ||
954 | if (!*pte_list) | |
955 | return; | |
956 | ||
957 | if (!(*pte_list & 1)) | |
958 | return fn((u64 *)*pte_list); | |
959 | ||
960 | desc = (struct pte_list_desc *)(*pte_list & ~1ul); | |
961 | while (desc) { | |
962 | for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i) | |
963 | fn(desc->sptes[i]); | |
964 | desc = desc->more; | |
965 | } | |
966 | } | |
967 | ||
9373e2c0 | 968 | static unsigned long *__gfn_to_rmap(gfn_t gfn, int level, |
9b9b1492 | 969 | struct kvm_memory_slot *slot) |
53c07b18 | 970 | { |
77d11309 | 971 | unsigned long idx; |
53c07b18 | 972 | |
53c07b18 XG |
973 | if (likely(level == PT_PAGE_TABLE_LEVEL)) |
974 | return &slot->rmap[gfn - slot->base_gfn]; | |
975 | ||
77d11309 TY |
976 | idx = gfn_to_index(gfn, slot->base_gfn, level); |
977 | return &slot->arch.rmap_pde[level - PT_DIRECTORY_LEVEL][idx]; | |
53c07b18 XG |
978 | } |
979 | ||
9b9b1492 TY |
980 | /* |
981 | * Take gfn and return the reverse mapping to it. | |
982 | */ | |
983 | static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, int level) | |
984 | { | |
985 | struct kvm_memory_slot *slot; | |
986 | ||
987 | slot = gfn_to_memslot(kvm, gfn); | |
9373e2c0 | 988 | return __gfn_to_rmap(gfn, level, slot); |
9b9b1492 TY |
989 | } |
990 | ||
f759e2b4 XG |
991 | static bool rmap_can_add(struct kvm_vcpu *vcpu) |
992 | { | |
993 | struct kvm_mmu_memory_cache *cache; | |
994 | ||
995 | cache = &vcpu->arch.mmu_pte_list_desc_cache; | |
996 | return mmu_memory_cache_free_objects(cache); | |
997 | } | |
998 | ||
53c07b18 XG |
999 | static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) |
1000 | { | |
1001 | struct kvm_mmu_page *sp; | |
1002 | unsigned long *rmapp; | |
1003 | ||
53c07b18 XG |
1004 | sp = page_header(__pa(spte)); |
1005 | kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn); | |
1006 | rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); | |
1007 | return pte_list_add(vcpu, spte, rmapp); | |
1008 | } | |
1009 | ||
53c07b18 XG |
1010 | static void rmap_remove(struct kvm *kvm, u64 *spte) |
1011 | { | |
1012 | struct kvm_mmu_page *sp; | |
1013 | gfn_t gfn; | |
1014 | unsigned long *rmapp; | |
1015 | ||
1016 | sp = page_header(__pa(spte)); | |
1017 | gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt); | |
1018 | rmapp = gfn_to_rmap(kvm, gfn, sp->role.level); | |
1019 | pte_list_remove(spte, rmapp); | |
1020 | } | |
1021 | ||
1e3f42f0 TY |
1022 | /* |
1023 | * Used by the following functions to iterate through the sptes linked by a | |
1024 | * rmap. All fields are private and not assumed to be used outside. | |
1025 | */ | |
1026 | struct rmap_iterator { | |
1027 | /* private fields */ | |
1028 | struct pte_list_desc *desc; /* holds the sptep if not NULL */ | |
1029 | int pos; /* index of the sptep */ | |
1030 | }; | |
1031 | ||
1032 | /* | |
1033 | * Iteration must be started by this function. This should also be used after | |
1034 | * removing/dropping sptes from the rmap link because in such cases the | |
1035 | * information in the itererator may not be valid. | |
1036 | * | |
1037 | * Returns sptep if found, NULL otherwise. | |
1038 | */ | |
1039 | static u64 *rmap_get_first(unsigned long rmap, struct rmap_iterator *iter) | |
1040 | { | |
1041 | if (!rmap) | |
1042 | return NULL; | |
1043 | ||
1044 | if (!(rmap & 1)) { | |
1045 | iter->desc = NULL; | |
1046 | return (u64 *)rmap; | |
1047 | } | |
1048 | ||
1049 | iter->desc = (struct pte_list_desc *)(rmap & ~1ul); | |
1050 | iter->pos = 0; | |
1051 | return iter->desc->sptes[iter->pos]; | |
1052 | } | |
1053 | ||
1054 | /* | |
1055 | * Must be used with a valid iterator: e.g. after rmap_get_first(). | |
1056 | * | |
1057 | * Returns sptep if found, NULL otherwise. | |
1058 | */ | |
1059 | static u64 *rmap_get_next(struct rmap_iterator *iter) | |
1060 | { | |
1061 | if (iter->desc) { | |
1062 | if (iter->pos < PTE_LIST_EXT - 1) { | |
1063 | u64 *sptep; | |
1064 | ||
1065 | ++iter->pos; | |
1066 | sptep = iter->desc->sptes[iter->pos]; | |
1067 | if (sptep) | |
1068 | return sptep; | |
1069 | } | |
1070 | ||
1071 | iter->desc = iter->desc->more; | |
1072 | ||
1073 | if (iter->desc) { | |
1074 | iter->pos = 0; | |
1075 | /* desc->sptes[0] cannot be NULL */ | |
1076 | return iter->desc->sptes[iter->pos]; | |
1077 | } | |
1078 | } | |
1079 | ||
1080 | return NULL; | |
1081 | } | |
1082 | ||
c3707958 | 1083 | static void drop_spte(struct kvm *kvm, u64 *sptep) |
e4b502ea | 1084 | { |
1df9f2dc | 1085 | if (mmu_spte_clear_track_bits(sptep)) |
eb45fda4 | 1086 | rmap_remove(kvm, sptep); |
be38d276 AK |
1087 | } |
1088 | ||
8e22f955 XG |
1089 | |
1090 | static bool __drop_large_spte(struct kvm *kvm, u64 *sptep) | |
1091 | { | |
1092 | if (is_large_pte(*sptep)) { | |
1093 | WARN_ON(page_header(__pa(sptep))->role.level == | |
1094 | PT_PAGE_TABLE_LEVEL); | |
1095 | drop_spte(kvm, sptep); | |
1096 | --kvm->stat.lpages; | |
1097 | return true; | |
1098 | } | |
1099 | ||
1100 | return false; | |
1101 | } | |
1102 | ||
1103 | static void drop_large_spte(struct kvm_vcpu *vcpu, u64 *sptep) | |
1104 | { | |
1105 | if (__drop_large_spte(vcpu->kvm, sptep)) | |
1106 | kvm_flush_remote_tlbs(vcpu->kvm); | |
1107 | } | |
1108 | ||
1109 | /* | |
49fde340 XG |
1110 | * Write-protect on the specified @sptep, @pt_protect indicates whether |
1111 | * spte writ-protection is caused by protecting shadow page table. | |
1112 | * @flush indicates whether tlb need be flushed. | |
1113 | * | |
1114 | * Note: write protection is difference between drity logging and spte | |
1115 | * protection: | |
1116 | * - for dirty logging, the spte can be set to writable at anytime if | |
1117 | * its dirty bitmap is properly set. | |
1118 | * - for spte protection, the spte can be writable only after unsync-ing | |
1119 | * shadow page. | |
8e22f955 XG |
1120 | * |
1121 | * Return true if the spte is dropped. | |
1122 | */ | |
49fde340 XG |
1123 | static bool |
1124 | spte_write_protect(struct kvm *kvm, u64 *sptep, bool *flush, bool pt_protect) | |
d13bc5b5 XG |
1125 | { |
1126 | u64 spte = *sptep; | |
1127 | ||
49fde340 XG |
1128 | if (!is_writable_pte(spte) && |
1129 | !(pt_protect && spte_is_locklessly_modifiable(spte))) | |
d13bc5b5 XG |
1130 | return false; |
1131 | ||
1132 | rmap_printk("rmap_write_protect: spte %p %llx\n", sptep, *sptep); | |
1133 | ||
49fde340 XG |
1134 | if (__drop_large_spte(kvm, sptep)) { |
1135 | *flush |= true; | |
d13bc5b5 | 1136 | return true; |
49fde340 | 1137 | } |
d13bc5b5 | 1138 | |
49fde340 XG |
1139 | if (pt_protect) |
1140 | spte &= ~SPTE_MMU_WRITEABLE; | |
d13bc5b5 | 1141 | spte = spte & ~PT_WRITABLE_MASK; |
49fde340 XG |
1142 | |
1143 | *flush |= mmu_spte_update(sptep, spte); | |
d13bc5b5 XG |
1144 | return false; |
1145 | } | |
1146 | ||
49fde340 XG |
1147 | static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, |
1148 | int level, bool pt_protect) | |
98348e95 | 1149 | { |
1e3f42f0 TY |
1150 | u64 *sptep; |
1151 | struct rmap_iterator iter; | |
d13bc5b5 | 1152 | bool flush = false; |
374cbac0 | 1153 | |
1e3f42f0 TY |
1154 | for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { |
1155 | BUG_ON(!(*sptep & PT_PRESENT_MASK)); | |
49fde340 | 1156 | if (spte_write_protect(kvm, sptep, &flush, pt_protect)) { |
1e3f42f0 | 1157 | sptep = rmap_get_first(*rmapp, &iter); |
d13bc5b5 | 1158 | continue; |
caa5b8a5 | 1159 | } |
a0ed4607 | 1160 | |
d13bc5b5 | 1161 | sptep = rmap_get_next(&iter); |
374cbac0 | 1162 | } |
855149aa | 1163 | |
d13bc5b5 | 1164 | return flush; |
a0ed4607 TY |
1165 | } |
1166 | ||
5dc99b23 TY |
1167 | /** |
1168 | * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages | |
1169 | * @kvm: kvm instance | |
1170 | * @slot: slot to protect | |
1171 | * @gfn_offset: start of the BITS_PER_LONG pages we care about | |
1172 | * @mask: indicates which pages we should protect | |
1173 | * | |
1174 | * Used when we do not need to care about huge page mappings: e.g. during dirty | |
1175 | * logging we do not have any such mappings. | |
1176 | */ | |
1177 | void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, | |
1178 | struct kvm_memory_slot *slot, | |
1179 | gfn_t gfn_offset, unsigned long mask) | |
a0ed4607 TY |
1180 | { |
1181 | unsigned long *rmapp; | |
a0ed4607 | 1182 | |
5dc99b23 TY |
1183 | while (mask) { |
1184 | rmapp = &slot->rmap[gfn_offset + __ffs(mask)]; | |
49fde340 | 1185 | __rmap_write_protect(kvm, rmapp, PT_PAGE_TABLE_LEVEL, false); |
05da4558 | 1186 | |
5dc99b23 TY |
1187 | /* clear the first set bit */ |
1188 | mask &= mask - 1; | |
1189 | } | |
374cbac0 AK |
1190 | } |
1191 | ||
2f84569f | 1192 | static bool rmap_write_protect(struct kvm *kvm, u64 gfn) |
95d4c16c TY |
1193 | { |
1194 | struct kvm_memory_slot *slot; | |
5dc99b23 TY |
1195 | unsigned long *rmapp; |
1196 | int i; | |
2f84569f | 1197 | bool write_protected = false; |
95d4c16c TY |
1198 | |
1199 | slot = gfn_to_memslot(kvm, gfn); | |
5dc99b23 TY |
1200 | |
1201 | for (i = PT_PAGE_TABLE_LEVEL; | |
1202 | i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { | |
1203 | rmapp = __gfn_to_rmap(gfn, i, slot); | |
49fde340 | 1204 | write_protected |= __rmap_write_protect(kvm, rmapp, i, true); |
5dc99b23 TY |
1205 | } |
1206 | ||
1207 | return write_protected; | |
95d4c16c TY |
1208 | } |
1209 | ||
8a8365c5 | 1210 | static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, |
048212d0 | 1211 | struct kvm_memory_slot *slot, unsigned long data) |
e930bffe | 1212 | { |
1e3f42f0 TY |
1213 | u64 *sptep; |
1214 | struct rmap_iterator iter; | |
e930bffe AA |
1215 | int need_tlb_flush = 0; |
1216 | ||
1e3f42f0 TY |
1217 | while ((sptep = rmap_get_first(*rmapp, &iter))) { |
1218 | BUG_ON(!(*sptep & PT_PRESENT_MASK)); | |
1219 | rmap_printk("kvm_rmap_unmap_hva: spte %p %llx\n", sptep, *sptep); | |
1220 | ||
1221 | drop_spte(kvm, sptep); | |
e930bffe AA |
1222 | need_tlb_flush = 1; |
1223 | } | |
1e3f42f0 | 1224 | |
e930bffe AA |
1225 | return need_tlb_flush; |
1226 | } | |
1227 | ||
8a8365c5 | 1228 | static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, |
048212d0 | 1229 | struct kvm_memory_slot *slot, unsigned long data) |
3da0dd43 | 1230 | { |
1e3f42f0 TY |
1231 | u64 *sptep; |
1232 | struct rmap_iterator iter; | |
3da0dd43 | 1233 | int need_flush = 0; |
1e3f42f0 | 1234 | u64 new_spte; |
3da0dd43 IE |
1235 | pte_t *ptep = (pte_t *)data; |
1236 | pfn_t new_pfn; | |
1237 | ||
1238 | WARN_ON(pte_huge(*ptep)); | |
1239 | new_pfn = pte_pfn(*ptep); | |
1e3f42f0 TY |
1240 | |
1241 | for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { | |
1242 | BUG_ON(!is_shadow_present_pte(*sptep)); | |
1243 | rmap_printk("kvm_set_pte_rmapp: spte %p %llx\n", sptep, *sptep); | |
1244 | ||
3da0dd43 | 1245 | need_flush = 1; |
1e3f42f0 | 1246 | |
3da0dd43 | 1247 | if (pte_write(*ptep)) { |
1e3f42f0 TY |
1248 | drop_spte(kvm, sptep); |
1249 | sptep = rmap_get_first(*rmapp, &iter); | |
3da0dd43 | 1250 | } else { |
1e3f42f0 | 1251 | new_spte = *sptep & ~PT64_BASE_ADDR_MASK; |
3da0dd43 IE |
1252 | new_spte |= (u64)new_pfn << PAGE_SHIFT; |
1253 | ||
1254 | new_spte &= ~PT_WRITABLE_MASK; | |
1255 | new_spte &= ~SPTE_HOST_WRITEABLE; | |
b79b93f9 | 1256 | new_spte &= ~shadow_accessed_mask; |
1e3f42f0 TY |
1257 | |
1258 | mmu_spte_clear_track_bits(sptep); | |
1259 | mmu_spte_set(sptep, new_spte); | |
1260 | sptep = rmap_get_next(&iter); | |
3da0dd43 IE |
1261 | } |
1262 | } | |
1e3f42f0 | 1263 | |
3da0dd43 IE |
1264 | if (need_flush) |
1265 | kvm_flush_remote_tlbs(kvm); | |
1266 | ||
1267 | return 0; | |
1268 | } | |
1269 | ||
84504ef3 TY |
1270 | static int kvm_handle_hva_range(struct kvm *kvm, |
1271 | unsigned long start, | |
1272 | unsigned long end, | |
1273 | unsigned long data, | |
1274 | int (*handler)(struct kvm *kvm, | |
1275 | unsigned long *rmapp, | |
048212d0 | 1276 | struct kvm_memory_slot *slot, |
84504ef3 | 1277 | unsigned long data)) |
e930bffe | 1278 | { |
be6ba0f0 | 1279 | int j; |
f395302e | 1280 | int ret = 0; |
bc6678a3 | 1281 | struct kvm_memslots *slots; |
be6ba0f0 | 1282 | struct kvm_memory_slot *memslot; |
bc6678a3 | 1283 | |
90d83dc3 | 1284 | slots = kvm_memslots(kvm); |
e930bffe | 1285 | |
be6ba0f0 | 1286 | kvm_for_each_memslot(memslot, slots) { |
84504ef3 | 1287 | unsigned long hva_start, hva_end; |
bcd3ef58 | 1288 | gfn_t gfn_start, gfn_end; |
852e3c19 | 1289 | |
84504ef3 TY |
1290 | hva_start = max(start, memslot->userspace_addr); |
1291 | hva_end = min(end, memslot->userspace_addr + | |
1292 | (memslot->npages << PAGE_SHIFT)); | |
1293 | if (hva_start >= hva_end) | |
1294 | continue; | |
1295 | /* | |
1296 | * {gfn(page) | page intersects with [hva_start, hva_end)} = | |
bcd3ef58 | 1297 | * {gfn_start, gfn_start+1, ..., gfn_end-1}. |
84504ef3 | 1298 | */ |
bcd3ef58 | 1299 | gfn_start = hva_to_gfn_memslot(hva_start, memslot); |
84504ef3 TY |
1300 | gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot); |
1301 | ||
bcd3ef58 TY |
1302 | for (j = PT_PAGE_TABLE_LEVEL; |
1303 | j < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++j) { | |
1304 | unsigned long idx, idx_end; | |
1305 | unsigned long *rmapp; | |
d4dbf470 | 1306 | |
bcd3ef58 TY |
1307 | /* |
1308 | * {idx(page_j) | page_j intersects with | |
1309 | * [hva_start, hva_end)} = {idx, idx+1, ..., idx_end}. | |
1310 | */ | |
1311 | idx = gfn_to_index(gfn_start, memslot->base_gfn, j); | |
1312 | idx_end = gfn_to_index(gfn_end - 1, memslot->base_gfn, j); | |
1313 | ||
1314 | rmapp = __gfn_to_rmap(gfn_start, j, memslot); | |
1315 | ||
1316 | for (; idx <= idx_end; ++idx) | |
1317 | ret |= handler(kvm, rmapp++, memslot, data); | |
e930bffe AA |
1318 | } |
1319 | } | |
1320 | ||
f395302e | 1321 | return ret; |
e930bffe AA |
1322 | } |
1323 | ||
84504ef3 TY |
1324 | static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, |
1325 | unsigned long data, | |
1326 | int (*handler)(struct kvm *kvm, unsigned long *rmapp, | |
048212d0 | 1327 | struct kvm_memory_slot *slot, |
84504ef3 TY |
1328 | unsigned long data)) |
1329 | { | |
1330 | return kvm_handle_hva_range(kvm, hva, hva + 1, data, handler); | |
1331 | } | |
1332 | ||
e930bffe AA |
1333 | int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) |
1334 | { | |
3da0dd43 IE |
1335 | return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp); |
1336 | } | |
1337 | ||
b3ae2096 TY |
1338 | int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) |
1339 | { | |
1340 | return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp); | |
1341 | } | |
1342 | ||
3da0dd43 IE |
1343 | void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) |
1344 | { | |
8a8365c5 | 1345 | kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); |
e930bffe AA |
1346 | } |
1347 | ||
8a8365c5 | 1348 | static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, |
048212d0 | 1349 | struct kvm_memory_slot *slot, unsigned long data) |
e930bffe | 1350 | { |
1e3f42f0 | 1351 | u64 *sptep; |
79f702a6 | 1352 | struct rmap_iterator uninitialized_var(iter); |
e930bffe AA |
1353 | int young = 0; |
1354 | ||
6316e1c8 | 1355 | /* |
3f6d8c8a XH |
1356 | * In case of absence of EPT Access and Dirty Bits supports, |
1357 | * emulate the accessed bit for EPT, by checking if this page has | |
6316e1c8 RR |
1358 | * an EPT mapping, and clearing it if it does. On the next access, |
1359 | * a new EPT mapping will be established. | |
1360 | * This has some overhead, but not as much as the cost of swapping | |
1361 | * out actively used pages or breaking up actively used hugepages. | |
1362 | */ | |
f395302e TY |
1363 | if (!shadow_accessed_mask) { |
1364 | young = kvm_unmap_rmapp(kvm, rmapp, slot, data); | |
1365 | goto out; | |
1366 | } | |
534e38b4 | 1367 | |
1e3f42f0 TY |
1368 | for (sptep = rmap_get_first(*rmapp, &iter); sptep; |
1369 | sptep = rmap_get_next(&iter)) { | |
3f6d8c8a | 1370 | BUG_ON(!is_shadow_present_pte(*sptep)); |
1e3f42f0 | 1371 | |
3f6d8c8a | 1372 | if (*sptep & shadow_accessed_mask) { |
e930bffe | 1373 | young = 1; |
3f6d8c8a XH |
1374 | clear_bit((ffs(shadow_accessed_mask) - 1), |
1375 | (unsigned long *)sptep); | |
e930bffe | 1376 | } |
e930bffe | 1377 | } |
f395302e TY |
1378 | out: |
1379 | /* @data has hva passed to kvm_age_hva(). */ | |
1380 | trace_kvm_age_page(data, slot, young); | |
e930bffe AA |
1381 | return young; |
1382 | } | |
1383 | ||
8ee53820 | 1384 | static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, |
048212d0 | 1385 | struct kvm_memory_slot *slot, unsigned long data) |
8ee53820 | 1386 | { |
1e3f42f0 TY |
1387 | u64 *sptep; |
1388 | struct rmap_iterator iter; | |
8ee53820 AA |
1389 | int young = 0; |
1390 | ||
1391 | /* | |
1392 | * If there's no access bit in the secondary pte set by the | |
1393 | * hardware it's up to gup-fast/gup to set the access bit in | |
1394 | * the primary pte or in the page structure. | |
1395 | */ | |
1396 | if (!shadow_accessed_mask) | |
1397 | goto out; | |
1398 | ||
1e3f42f0 TY |
1399 | for (sptep = rmap_get_first(*rmapp, &iter); sptep; |
1400 | sptep = rmap_get_next(&iter)) { | |
3f6d8c8a | 1401 | BUG_ON(!is_shadow_present_pte(*sptep)); |
1e3f42f0 | 1402 | |
3f6d8c8a | 1403 | if (*sptep & shadow_accessed_mask) { |
8ee53820 AA |
1404 | young = 1; |
1405 | break; | |
1406 | } | |
8ee53820 AA |
1407 | } |
1408 | out: | |
1409 | return young; | |
1410 | } | |
1411 | ||
53a27b39 MT |
1412 | #define RMAP_RECYCLE_THRESHOLD 1000 |
1413 | ||
852e3c19 | 1414 | static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn) |
53a27b39 MT |
1415 | { |
1416 | unsigned long *rmapp; | |
852e3c19 JR |
1417 | struct kvm_mmu_page *sp; |
1418 | ||
1419 | sp = page_header(__pa(spte)); | |
53a27b39 | 1420 | |
852e3c19 | 1421 | rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level); |
53a27b39 | 1422 | |
048212d0 | 1423 | kvm_unmap_rmapp(vcpu->kvm, rmapp, NULL, 0); |
53a27b39 MT |
1424 | kvm_flush_remote_tlbs(vcpu->kvm); |
1425 | } | |
1426 | ||
e930bffe AA |
1427 | int kvm_age_hva(struct kvm *kvm, unsigned long hva) |
1428 | { | |
f395302e | 1429 | return kvm_handle_hva(kvm, hva, hva, kvm_age_rmapp); |
e930bffe AA |
1430 | } |
1431 | ||
8ee53820 AA |
1432 | int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) |
1433 | { | |
1434 | return kvm_handle_hva(kvm, hva, 0, kvm_test_age_rmapp); | |
1435 | } | |
1436 | ||
d6c69ee9 | 1437 | #ifdef MMU_DEBUG |
47ad8e68 | 1438 | static int is_empty_shadow_page(u64 *spt) |
6aa8b732 | 1439 | { |
139bdb2d AK |
1440 | u64 *pos; |
1441 | u64 *end; | |
1442 | ||
47ad8e68 | 1443 | for (pos = spt, end = pos + PAGE_SIZE / sizeof(u64); pos != end; pos++) |
3c915510 | 1444 | if (is_shadow_present_pte(*pos)) { |
b8688d51 | 1445 | printk(KERN_ERR "%s: %p %llx\n", __func__, |
139bdb2d | 1446 | pos, *pos); |
6aa8b732 | 1447 | return 0; |
139bdb2d | 1448 | } |
6aa8b732 AK |
1449 | return 1; |
1450 | } | |
d6c69ee9 | 1451 | #endif |
6aa8b732 | 1452 | |
45221ab6 DH |
1453 | /* |
1454 | * This value is the sum of all of the kvm instances's | |
1455 | * kvm->arch.n_used_mmu_pages values. We need a global, | |
1456 | * aggregate version in order to make the slab shrinker | |
1457 | * faster | |
1458 | */ | |
1459 | static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr) | |
1460 | { | |
1461 | kvm->arch.n_used_mmu_pages += nr; | |
1462 | percpu_counter_add(&kvm_total_used_mmu_pages, nr); | |
1463 | } | |
1464 | ||
bd4c86ea XG |
1465 | /* |
1466 | * Remove the sp from shadow page cache, after call it, | |
1467 | * we can not find this sp from the cache, and the shadow | |
1468 | * page table is still valid. | |
1469 | * It should be under the protection of mmu lock. | |
1470 | */ | |
1471 | static void kvm_mmu_isolate_page(struct kvm_mmu_page *sp) | |
260746c0 | 1472 | { |
4db35314 | 1473 | ASSERT(is_empty_shadow_page(sp->spt)); |
7775834a | 1474 | hlist_del(&sp->hash_link); |
2032a93d | 1475 | if (!sp->role.direct) |
842f22ed | 1476 | free_page((unsigned long)sp->gfns); |
bd4c86ea XG |
1477 | } |
1478 | ||
1479 | /* | |
1480 | * Free the shadow page table and the sp, we can do it | |
1481 | * out of the protection of mmu lock. | |
1482 | */ | |
1483 | static void kvm_mmu_free_page(struct kvm_mmu_page *sp) | |
1484 | { | |
1485 | list_del(&sp->link); | |
1486 | free_page((unsigned long)sp->spt); | |
e8ad9a70 | 1487 | kmem_cache_free(mmu_page_header_cache, sp); |
260746c0 AK |
1488 | } |
1489 | ||
cea0f0e7 AK |
1490 | static unsigned kvm_page_table_hashfn(gfn_t gfn) |
1491 | { | |
1ae0a13d | 1492 | return gfn & ((1 << KVM_MMU_HASH_SHIFT) - 1); |
cea0f0e7 AK |
1493 | } |
1494 | ||
714b93da | 1495 | static void mmu_page_add_parent_pte(struct kvm_vcpu *vcpu, |
4db35314 | 1496 | struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 | 1497 | { |
cea0f0e7 AK |
1498 | if (!parent_pte) |
1499 | return; | |
cea0f0e7 | 1500 | |
67052b35 | 1501 | pte_list_add(vcpu, parent_pte, &sp->parent_ptes); |
cea0f0e7 AK |
1502 | } |
1503 | ||
4db35314 | 1504 | static void mmu_page_remove_parent_pte(struct kvm_mmu_page *sp, |
cea0f0e7 AK |
1505 | u64 *parent_pte) |
1506 | { | |
67052b35 | 1507 | pte_list_remove(parent_pte, &sp->parent_ptes); |
cea0f0e7 AK |
1508 | } |
1509 | ||
bcdd9a93 XG |
1510 | static void drop_parent_pte(struct kvm_mmu_page *sp, |
1511 | u64 *parent_pte) | |
1512 | { | |
1513 | mmu_page_remove_parent_pte(sp, parent_pte); | |
1df9f2dc | 1514 | mmu_spte_clear_no_track(parent_pte); |
bcdd9a93 XG |
1515 | } |
1516 | ||
67052b35 XG |
1517 | static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, |
1518 | u64 *parent_pte, int direct) | |
ad8cfbe3 | 1519 | { |
67052b35 | 1520 | struct kvm_mmu_page *sp; |
80feb89a TY |
1521 | sp = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_header_cache); |
1522 | sp->spt = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache); | |
67052b35 | 1523 | if (!direct) |
80feb89a | 1524 | sp->gfns = mmu_memory_cache_alloc(&vcpu->arch.mmu_page_cache); |
67052b35 XG |
1525 | set_page_private(virt_to_page(sp->spt), (unsigned long)sp); |
1526 | list_add(&sp->link, &vcpu->kvm->arch.active_mmu_pages); | |
93a5cef0 | 1527 | bitmap_zero(sp->slot_bitmap, KVM_MEM_SLOTS_NUM); |
67052b35 XG |
1528 | sp->parent_ptes = 0; |
1529 | mmu_page_add_parent_pte(vcpu, sp, parent_pte); | |
1530 | kvm_mod_used_mmu_pages(vcpu->kvm, +1); | |
1531 | return sp; | |
ad8cfbe3 MT |
1532 | } |
1533 | ||
67052b35 | 1534 | static void mark_unsync(u64 *spte); |
1047df1f | 1535 | static void kvm_mmu_mark_parents_unsync(struct kvm_mmu_page *sp) |
0074ff63 | 1536 | { |
67052b35 | 1537 | pte_list_walk(&sp->parent_ptes, mark_unsync); |
0074ff63 MT |
1538 | } |
1539 | ||
67052b35 | 1540 | static void mark_unsync(u64 *spte) |
0074ff63 | 1541 | { |
67052b35 | 1542 | struct kvm_mmu_page *sp; |
1047df1f | 1543 | unsigned int index; |
0074ff63 | 1544 | |
67052b35 | 1545 | sp = page_header(__pa(spte)); |
1047df1f XG |
1546 | index = spte - sp->spt; |
1547 | if (__test_and_set_bit(index, sp->unsync_child_bitmap)) | |
0074ff63 | 1548 | return; |
1047df1f | 1549 | if (sp->unsync_children++) |
0074ff63 | 1550 | return; |
1047df1f | 1551 | kvm_mmu_mark_parents_unsync(sp); |
0074ff63 MT |
1552 | } |
1553 | ||
e8bc217a | 1554 | static int nonpaging_sync_page(struct kvm_vcpu *vcpu, |
a4a8e6f7 | 1555 | struct kvm_mmu_page *sp) |
e8bc217a MT |
1556 | { |
1557 | return 1; | |
1558 | } | |
1559 | ||
a7052897 MT |
1560 | static void nonpaging_invlpg(struct kvm_vcpu *vcpu, gva_t gva) |
1561 | { | |
1562 | } | |
1563 | ||
0f53b5b1 XG |
1564 | static void nonpaging_update_pte(struct kvm_vcpu *vcpu, |
1565 | struct kvm_mmu_page *sp, u64 *spte, | |
7c562522 | 1566 | const void *pte) |
0f53b5b1 XG |
1567 | { |
1568 | WARN_ON(1); | |
1569 | } | |
1570 | ||
60c8aec6 MT |
1571 | #define KVM_PAGE_ARRAY_NR 16 |
1572 | ||
1573 | struct kvm_mmu_pages { | |
1574 | struct mmu_page_and_offset { | |
1575 | struct kvm_mmu_page *sp; | |
1576 | unsigned int idx; | |
1577 | } page[KVM_PAGE_ARRAY_NR]; | |
1578 | unsigned int nr; | |
1579 | }; | |
1580 | ||
cded19f3 HE |
1581 | static int mmu_pages_add(struct kvm_mmu_pages *pvec, struct kvm_mmu_page *sp, |
1582 | int idx) | |
4731d4c7 | 1583 | { |
60c8aec6 | 1584 | int i; |
4731d4c7 | 1585 | |
60c8aec6 MT |
1586 | if (sp->unsync) |
1587 | for (i=0; i < pvec->nr; i++) | |
1588 | if (pvec->page[i].sp == sp) | |
1589 | return 0; | |
1590 | ||
1591 | pvec->page[pvec->nr].sp = sp; | |
1592 | pvec->page[pvec->nr].idx = idx; | |
1593 | pvec->nr++; | |
1594 | return (pvec->nr == KVM_PAGE_ARRAY_NR); | |
1595 | } | |
1596 | ||
1597 | static int __mmu_unsync_walk(struct kvm_mmu_page *sp, | |
1598 | struct kvm_mmu_pages *pvec) | |
1599 | { | |
1600 | int i, ret, nr_unsync_leaf = 0; | |
4731d4c7 | 1601 | |
37178b8b | 1602 | for_each_set_bit(i, sp->unsync_child_bitmap, 512) { |
7a8f1a74 | 1603 | struct kvm_mmu_page *child; |
4731d4c7 MT |
1604 | u64 ent = sp->spt[i]; |
1605 | ||
7a8f1a74 XG |
1606 | if (!is_shadow_present_pte(ent) || is_large_pte(ent)) |
1607 | goto clear_child_bitmap; | |
1608 | ||
1609 | child = page_header(ent & PT64_BASE_ADDR_MASK); | |
1610 | ||
1611 | if (child->unsync_children) { | |
1612 | if (mmu_pages_add(pvec, child, i)) | |
1613 | return -ENOSPC; | |
1614 | ||
1615 | ret = __mmu_unsync_walk(child, pvec); | |
1616 | if (!ret) | |
1617 | goto clear_child_bitmap; | |
1618 | else if (ret > 0) | |
1619 | nr_unsync_leaf += ret; | |
1620 | else | |
1621 | return ret; | |
1622 | } else if (child->unsync) { | |
1623 | nr_unsync_leaf++; | |
1624 | if (mmu_pages_add(pvec, child, i)) | |
1625 | return -ENOSPC; | |
1626 | } else | |
1627 | goto clear_child_bitmap; | |
1628 | ||
1629 | continue; | |
1630 | ||
1631 | clear_child_bitmap: | |
1632 | __clear_bit(i, sp->unsync_child_bitmap); | |
1633 | sp->unsync_children--; | |
1634 | WARN_ON((int)sp->unsync_children < 0); | |
4731d4c7 MT |
1635 | } |
1636 | ||
4731d4c7 | 1637 | |
60c8aec6 MT |
1638 | return nr_unsync_leaf; |
1639 | } | |
1640 | ||
1641 | static int mmu_unsync_walk(struct kvm_mmu_page *sp, | |
1642 | struct kvm_mmu_pages *pvec) | |
1643 | { | |
1644 | if (!sp->unsync_children) | |
1645 | return 0; | |
1646 | ||
1647 | mmu_pages_add(pvec, sp, 0); | |
1648 | return __mmu_unsync_walk(sp, pvec); | |
4731d4c7 MT |
1649 | } |
1650 | ||
4731d4c7 MT |
1651 | static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp) |
1652 | { | |
1653 | WARN_ON(!sp->unsync); | |
5e1b3ddb | 1654 | trace_kvm_mmu_sync_page(sp); |
4731d4c7 MT |
1655 | sp->unsync = 0; |
1656 | --kvm->stat.mmu_unsync; | |
1657 | } | |
1658 | ||
7775834a XG |
1659 | static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, |
1660 | struct list_head *invalid_list); | |
1661 | static void kvm_mmu_commit_zap_page(struct kvm *kvm, | |
1662 | struct list_head *invalid_list); | |
4731d4c7 | 1663 | |
f41d335a XG |
1664 | #define for_each_gfn_sp(kvm, sp, gfn, pos) \ |
1665 | hlist_for_each_entry(sp, pos, \ | |
7ae680eb XG |
1666 | &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \ |
1667 | if ((sp)->gfn != (gfn)) {} else | |
1668 | ||
f41d335a XG |
1669 | #define for_each_gfn_indirect_valid_sp(kvm, sp, gfn, pos) \ |
1670 | hlist_for_each_entry(sp, pos, \ | |
7ae680eb XG |
1671 | &(kvm)->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)], hash_link) \ |
1672 | if ((sp)->gfn != (gfn) || (sp)->role.direct || \ | |
1673 | (sp)->role.invalid) {} else | |
1674 | ||
f918b443 | 1675 | /* @sp->gfn should be write-protected at the call site */ |
1d9dc7e0 | 1676 | static int __kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, |
d98ba053 | 1677 | struct list_head *invalid_list, bool clear_unsync) |
4731d4c7 | 1678 | { |
5b7e0102 | 1679 | if (sp->role.cr4_pae != !!is_pae(vcpu)) { |
d98ba053 | 1680 | kvm_mmu_prepare_zap_page(vcpu->kvm, sp, invalid_list); |
4731d4c7 MT |
1681 | return 1; |
1682 | } | |
1683 | ||
f918b443 | 1684 | if (clear_unsync) |
1d9dc7e0 | 1685 | kvm_unlink_unsync_page(vcpu->kvm, sp); |
1d9dc7e0 | 1686 | |
a4a8e6f7 | 1687 | if (vcpu->arch.mmu.sync_page(vcpu, sp)) { |
d98ba053 | 1688 | kvm_mmu_prepare_zap_page(vcpu->kvm, sp, invalid_list); |
4731d4c7 MT |
1689 | return 1; |
1690 | } | |
1691 | ||
1692 | kvm_mmu_flush_tlb(vcpu); | |
4731d4c7 MT |
1693 | return 0; |
1694 | } | |
1695 | ||
1d9dc7e0 XG |
1696 | static int kvm_sync_page_transient(struct kvm_vcpu *vcpu, |
1697 | struct kvm_mmu_page *sp) | |
1698 | { | |
d98ba053 | 1699 | LIST_HEAD(invalid_list); |
1d9dc7e0 XG |
1700 | int ret; |
1701 | ||
d98ba053 | 1702 | ret = __kvm_sync_page(vcpu, sp, &invalid_list, false); |
be71e061 | 1703 | if (ret) |
d98ba053 XG |
1704 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
1705 | ||
1d9dc7e0 XG |
1706 | return ret; |
1707 | } | |
1708 | ||
e37fa785 XG |
1709 | #ifdef CONFIG_KVM_MMU_AUDIT |
1710 | #include "mmu_audit.c" | |
1711 | #else | |
1712 | static void kvm_mmu_audit(struct kvm_vcpu *vcpu, int point) { } | |
1713 | static void mmu_audit_disable(void) { } | |
1714 | #endif | |
1715 | ||
d98ba053 XG |
1716 | static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, |
1717 | struct list_head *invalid_list) | |
1d9dc7e0 | 1718 | { |
d98ba053 | 1719 | return __kvm_sync_page(vcpu, sp, invalid_list, true); |
1d9dc7e0 XG |
1720 | } |
1721 | ||
9f1a122f XG |
1722 | /* @gfn should be write-protected at the call site */ |
1723 | static void kvm_sync_pages(struct kvm_vcpu *vcpu, gfn_t gfn) | |
1724 | { | |
9f1a122f | 1725 | struct kvm_mmu_page *s; |
f41d335a | 1726 | struct hlist_node *node; |
d98ba053 | 1727 | LIST_HEAD(invalid_list); |
9f1a122f XG |
1728 | bool flush = false; |
1729 | ||
f41d335a | 1730 | for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node) { |
7ae680eb | 1731 | if (!s->unsync) |
9f1a122f XG |
1732 | continue; |
1733 | ||
1734 | WARN_ON(s->role.level != PT_PAGE_TABLE_LEVEL); | |
a4a8e6f7 | 1735 | kvm_unlink_unsync_page(vcpu->kvm, s); |
9f1a122f | 1736 | if ((s->role.cr4_pae != !!is_pae(vcpu)) || |
a4a8e6f7 | 1737 | (vcpu->arch.mmu.sync_page(vcpu, s))) { |
d98ba053 | 1738 | kvm_mmu_prepare_zap_page(vcpu->kvm, s, &invalid_list); |
9f1a122f XG |
1739 | continue; |
1740 | } | |
9f1a122f XG |
1741 | flush = true; |
1742 | } | |
1743 | ||
d98ba053 | 1744 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
9f1a122f XG |
1745 | if (flush) |
1746 | kvm_mmu_flush_tlb(vcpu); | |
1747 | } | |
1748 | ||
60c8aec6 MT |
1749 | struct mmu_page_path { |
1750 | struct kvm_mmu_page *parent[PT64_ROOT_LEVEL-1]; | |
1751 | unsigned int idx[PT64_ROOT_LEVEL-1]; | |
4731d4c7 MT |
1752 | }; |
1753 | ||
60c8aec6 MT |
1754 | #define for_each_sp(pvec, sp, parents, i) \ |
1755 | for (i = mmu_pages_next(&pvec, &parents, -1), \ | |
1756 | sp = pvec.page[i].sp; \ | |
1757 | i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \ | |
1758 | i = mmu_pages_next(&pvec, &parents, i)) | |
1759 | ||
cded19f3 HE |
1760 | static int mmu_pages_next(struct kvm_mmu_pages *pvec, |
1761 | struct mmu_page_path *parents, | |
1762 | int i) | |
60c8aec6 MT |
1763 | { |
1764 | int n; | |
1765 | ||
1766 | for (n = i+1; n < pvec->nr; n++) { | |
1767 | struct kvm_mmu_page *sp = pvec->page[n].sp; | |
1768 | ||
1769 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) { | |
1770 | parents->idx[0] = pvec->page[n].idx; | |
1771 | return n; | |
1772 | } | |
1773 | ||
1774 | parents->parent[sp->role.level-2] = sp; | |
1775 | parents->idx[sp->role.level-1] = pvec->page[n].idx; | |
1776 | } | |
1777 | ||
1778 | return n; | |
1779 | } | |
1780 | ||
cded19f3 | 1781 | static void mmu_pages_clear_parents(struct mmu_page_path *parents) |
4731d4c7 | 1782 | { |
60c8aec6 MT |
1783 | struct kvm_mmu_page *sp; |
1784 | unsigned int level = 0; | |
1785 | ||
1786 | do { | |
1787 | unsigned int idx = parents->idx[level]; | |
4731d4c7 | 1788 | |
60c8aec6 MT |
1789 | sp = parents->parent[level]; |
1790 | if (!sp) | |
1791 | return; | |
1792 | ||
1793 | --sp->unsync_children; | |
1794 | WARN_ON((int)sp->unsync_children < 0); | |
1795 | __clear_bit(idx, sp->unsync_child_bitmap); | |
1796 | level++; | |
1797 | } while (level < PT64_ROOT_LEVEL-1 && !sp->unsync_children); | |
4731d4c7 MT |
1798 | } |
1799 | ||
60c8aec6 MT |
1800 | static void kvm_mmu_pages_init(struct kvm_mmu_page *parent, |
1801 | struct mmu_page_path *parents, | |
1802 | struct kvm_mmu_pages *pvec) | |
4731d4c7 | 1803 | { |
60c8aec6 MT |
1804 | parents->parent[parent->role.level-1] = NULL; |
1805 | pvec->nr = 0; | |
1806 | } | |
4731d4c7 | 1807 | |
60c8aec6 MT |
1808 | static void mmu_sync_children(struct kvm_vcpu *vcpu, |
1809 | struct kvm_mmu_page *parent) | |
1810 | { | |
1811 | int i; | |
1812 | struct kvm_mmu_page *sp; | |
1813 | struct mmu_page_path parents; | |
1814 | struct kvm_mmu_pages pages; | |
d98ba053 | 1815 | LIST_HEAD(invalid_list); |
60c8aec6 MT |
1816 | |
1817 | kvm_mmu_pages_init(parent, &parents, &pages); | |
1818 | while (mmu_unsync_walk(parent, &pages)) { | |
2f84569f | 1819 | bool protected = false; |
b1a36821 MT |
1820 | |
1821 | for_each_sp(pages, sp, parents, i) | |
1822 | protected |= rmap_write_protect(vcpu->kvm, sp->gfn); | |
1823 | ||
1824 | if (protected) | |
1825 | kvm_flush_remote_tlbs(vcpu->kvm); | |
1826 | ||
60c8aec6 | 1827 | for_each_sp(pages, sp, parents, i) { |
d98ba053 | 1828 | kvm_sync_page(vcpu, sp, &invalid_list); |
60c8aec6 MT |
1829 | mmu_pages_clear_parents(&parents); |
1830 | } | |
d98ba053 | 1831 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
4731d4c7 | 1832 | cond_resched_lock(&vcpu->kvm->mmu_lock); |
60c8aec6 MT |
1833 | kvm_mmu_pages_init(parent, &parents, &pages); |
1834 | } | |
4731d4c7 MT |
1835 | } |
1836 | ||
c3707958 XG |
1837 | static void init_shadow_page_table(struct kvm_mmu_page *sp) |
1838 | { | |
1839 | int i; | |
1840 | ||
1841 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) | |
1842 | sp->spt[i] = 0ull; | |
1843 | } | |
1844 | ||
a30f47cb XG |
1845 | static void __clear_sp_write_flooding_count(struct kvm_mmu_page *sp) |
1846 | { | |
1847 | sp->write_flooding_count = 0; | |
1848 | } | |
1849 | ||
1850 | static void clear_sp_write_flooding_count(u64 *spte) | |
1851 | { | |
1852 | struct kvm_mmu_page *sp = page_header(__pa(spte)); | |
1853 | ||
1854 | __clear_sp_write_flooding_count(sp); | |
1855 | } | |
1856 | ||
cea0f0e7 AK |
1857 | static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, |
1858 | gfn_t gfn, | |
1859 | gva_t gaddr, | |
1860 | unsigned level, | |
f6e2c02b | 1861 | int direct, |
41074d07 | 1862 | unsigned access, |
f7d9c7b7 | 1863 | u64 *parent_pte) |
cea0f0e7 AK |
1864 | { |
1865 | union kvm_mmu_page_role role; | |
cea0f0e7 | 1866 | unsigned quadrant; |
9f1a122f | 1867 | struct kvm_mmu_page *sp; |
f41d335a | 1868 | struct hlist_node *node; |
9f1a122f | 1869 | bool need_sync = false; |
cea0f0e7 | 1870 | |
a770f6f2 | 1871 | role = vcpu->arch.mmu.base_role; |
cea0f0e7 | 1872 | role.level = level; |
f6e2c02b | 1873 | role.direct = direct; |
84b0c8c6 | 1874 | if (role.direct) |
5b7e0102 | 1875 | role.cr4_pae = 0; |
41074d07 | 1876 | role.access = access; |
c5a78f2b JR |
1877 | if (!vcpu->arch.mmu.direct_map |
1878 | && vcpu->arch.mmu.root_level <= PT32_ROOT_LEVEL) { | |
cea0f0e7 AK |
1879 | quadrant = gaddr >> (PAGE_SHIFT + (PT64_PT_BITS * level)); |
1880 | quadrant &= (1 << ((PT32_PT_BITS - PT64_PT_BITS) * level)) - 1; | |
1881 | role.quadrant = quadrant; | |
1882 | } | |
f41d335a | 1883 | for_each_gfn_sp(vcpu->kvm, sp, gfn, node) { |
7ae680eb XG |
1884 | if (!need_sync && sp->unsync) |
1885 | need_sync = true; | |
4731d4c7 | 1886 | |
7ae680eb XG |
1887 | if (sp->role.word != role.word) |
1888 | continue; | |
4731d4c7 | 1889 | |
7ae680eb XG |
1890 | if (sp->unsync && kvm_sync_page_transient(vcpu, sp)) |
1891 | break; | |
e02aa901 | 1892 | |
7ae680eb XG |
1893 | mmu_page_add_parent_pte(vcpu, sp, parent_pte); |
1894 | if (sp->unsync_children) { | |
a8eeb04a | 1895 | kvm_make_request(KVM_REQ_MMU_SYNC, vcpu); |
7ae680eb XG |
1896 | kvm_mmu_mark_parents_unsync(sp); |
1897 | } else if (sp->unsync) | |
1898 | kvm_mmu_mark_parents_unsync(sp); | |
e02aa901 | 1899 | |
a30f47cb | 1900 | __clear_sp_write_flooding_count(sp); |
7ae680eb XG |
1901 | trace_kvm_mmu_get_page(sp, false); |
1902 | return sp; | |
1903 | } | |
dfc5aa00 | 1904 | ++vcpu->kvm->stat.mmu_cache_miss; |
2032a93d | 1905 | sp = kvm_mmu_alloc_page(vcpu, parent_pte, direct); |
4db35314 AK |
1906 | if (!sp) |
1907 | return sp; | |
4db35314 AK |
1908 | sp->gfn = gfn; |
1909 | sp->role = role; | |
7ae680eb XG |
1910 | hlist_add_head(&sp->hash_link, |
1911 | &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]); | |
f6e2c02b | 1912 | if (!direct) { |
b1a36821 MT |
1913 | if (rmap_write_protect(vcpu->kvm, gfn)) |
1914 | kvm_flush_remote_tlbs(vcpu->kvm); | |
9f1a122f XG |
1915 | if (level > PT_PAGE_TABLE_LEVEL && need_sync) |
1916 | kvm_sync_pages(vcpu, gfn); | |
1917 | ||
4731d4c7 MT |
1918 | account_shadowed(vcpu->kvm, gfn); |
1919 | } | |
c3707958 | 1920 | init_shadow_page_table(sp); |
f691fe1d | 1921 | trace_kvm_mmu_get_page(sp, true); |
4db35314 | 1922 | return sp; |
cea0f0e7 AK |
1923 | } |
1924 | ||
2d11123a AK |
1925 | static void shadow_walk_init(struct kvm_shadow_walk_iterator *iterator, |
1926 | struct kvm_vcpu *vcpu, u64 addr) | |
1927 | { | |
1928 | iterator->addr = addr; | |
1929 | iterator->shadow_addr = vcpu->arch.mmu.root_hpa; | |
1930 | iterator->level = vcpu->arch.mmu.shadow_root_level; | |
81407ca5 JR |
1931 | |
1932 | if (iterator->level == PT64_ROOT_LEVEL && | |
1933 | vcpu->arch.mmu.root_level < PT64_ROOT_LEVEL && | |
1934 | !vcpu->arch.mmu.direct_map) | |
1935 | --iterator->level; | |
1936 | ||
2d11123a AK |
1937 | if (iterator->level == PT32E_ROOT_LEVEL) { |
1938 | iterator->shadow_addr | |
1939 | = vcpu->arch.mmu.pae_root[(addr >> 30) & 3]; | |
1940 | iterator->shadow_addr &= PT64_BASE_ADDR_MASK; | |
1941 | --iterator->level; | |
1942 | if (!iterator->shadow_addr) | |
1943 | iterator->level = 0; | |
1944 | } | |
1945 | } | |
1946 | ||
1947 | static bool shadow_walk_okay(struct kvm_shadow_walk_iterator *iterator) | |
1948 | { | |
1949 | if (iterator->level < PT_PAGE_TABLE_LEVEL) | |
1950 | return false; | |
4d88954d | 1951 | |
2d11123a AK |
1952 | iterator->index = SHADOW_PT_INDEX(iterator->addr, iterator->level); |
1953 | iterator->sptep = ((u64 *)__va(iterator->shadow_addr)) + iterator->index; | |
1954 | return true; | |
1955 | } | |
1956 | ||
c2a2ac2b XG |
1957 | static void __shadow_walk_next(struct kvm_shadow_walk_iterator *iterator, |
1958 | u64 spte) | |
2d11123a | 1959 | { |
c2a2ac2b | 1960 | if (is_last_spte(spte, iterator->level)) { |
052331be XG |
1961 | iterator->level = 0; |
1962 | return; | |
1963 | } | |
1964 | ||
c2a2ac2b | 1965 | iterator->shadow_addr = spte & PT64_BASE_ADDR_MASK; |
2d11123a AK |
1966 | --iterator->level; |
1967 | } | |
1968 | ||
c2a2ac2b XG |
1969 | static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator) |
1970 | { | |
1971 | return __shadow_walk_next(iterator, *iterator->sptep); | |
1972 | } | |
1973 | ||
32ef26a3 AK |
1974 | static void link_shadow_page(u64 *sptep, struct kvm_mmu_page *sp) |
1975 | { | |
1976 | u64 spte; | |
1977 | ||
1978 | spte = __pa(sp->spt) | |
1979 | | PT_PRESENT_MASK | PT_ACCESSED_MASK | |
1980 | | PT_WRITABLE_MASK | PT_USER_MASK; | |
1df9f2dc | 1981 | mmu_spte_set(sptep, spte); |
32ef26a3 AK |
1982 | } |
1983 | ||
a357bd22 AK |
1984 | static void validate_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, |
1985 | unsigned direct_access) | |
1986 | { | |
1987 | if (is_shadow_present_pte(*sptep) && !is_large_pte(*sptep)) { | |
1988 | struct kvm_mmu_page *child; | |
1989 | ||
1990 | /* | |
1991 | * For the direct sp, if the guest pte's dirty bit | |
1992 | * changed form clean to dirty, it will corrupt the | |
1993 | * sp's access: allow writable in the read-only sp, | |
1994 | * so we should update the spte at this point to get | |
1995 | * a new sp with the correct access. | |
1996 | */ | |
1997 | child = page_header(*sptep & PT64_BASE_ADDR_MASK); | |
1998 | if (child->role.access == direct_access) | |
1999 | return; | |
2000 | ||
bcdd9a93 | 2001 | drop_parent_pte(child, sptep); |
a357bd22 AK |
2002 | kvm_flush_remote_tlbs(vcpu->kvm); |
2003 | } | |
2004 | } | |
2005 | ||
505aef8f | 2006 | static bool mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp, |
38e3b2b2 XG |
2007 | u64 *spte) |
2008 | { | |
2009 | u64 pte; | |
2010 | struct kvm_mmu_page *child; | |
2011 | ||
2012 | pte = *spte; | |
2013 | if (is_shadow_present_pte(pte)) { | |
505aef8f | 2014 | if (is_last_spte(pte, sp->role.level)) { |
c3707958 | 2015 | drop_spte(kvm, spte); |
505aef8f XG |
2016 | if (is_large_pte(pte)) |
2017 | --kvm->stat.lpages; | |
2018 | } else { | |
38e3b2b2 | 2019 | child = page_header(pte & PT64_BASE_ADDR_MASK); |
bcdd9a93 | 2020 | drop_parent_pte(child, spte); |
38e3b2b2 | 2021 | } |
505aef8f XG |
2022 | return true; |
2023 | } | |
2024 | ||
2025 | if (is_mmio_spte(pte)) | |
ce88decf | 2026 | mmu_spte_clear_no_track(spte); |
c3707958 | 2027 | |
505aef8f | 2028 | return false; |
38e3b2b2 XG |
2029 | } |
2030 | ||
90cb0529 | 2031 | static void kvm_mmu_page_unlink_children(struct kvm *kvm, |
4db35314 | 2032 | struct kvm_mmu_page *sp) |
a436036b | 2033 | { |
697fe2e2 | 2034 | unsigned i; |
697fe2e2 | 2035 | |
38e3b2b2 XG |
2036 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) |
2037 | mmu_page_zap_pte(kvm, sp, sp->spt + i); | |
a436036b AK |
2038 | } |
2039 | ||
4db35314 | 2040 | static void kvm_mmu_put_page(struct kvm_mmu_page *sp, u64 *parent_pte) |
cea0f0e7 | 2041 | { |
4db35314 | 2042 | mmu_page_remove_parent_pte(sp, parent_pte); |
a436036b AK |
2043 | } |
2044 | ||
31aa2b44 | 2045 | static void kvm_mmu_unlink_parents(struct kvm *kvm, struct kvm_mmu_page *sp) |
a436036b | 2046 | { |
1e3f42f0 TY |
2047 | u64 *sptep; |
2048 | struct rmap_iterator iter; | |
a436036b | 2049 | |
1e3f42f0 TY |
2050 | while ((sptep = rmap_get_first(sp->parent_ptes, &iter))) |
2051 | drop_parent_pte(sp, sptep); | |
31aa2b44 AK |
2052 | } |
2053 | ||
60c8aec6 | 2054 | static int mmu_zap_unsync_children(struct kvm *kvm, |
7775834a XG |
2055 | struct kvm_mmu_page *parent, |
2056 | struct list_head *invalid_list) | |
4731d4c7 | 2057 | { |
60c8aec6 MT |
2058 | int i, zapped = 0; |
2059 | struct mmu_page_path parents; | |
2060 | struct kvm_mmu_pages pages; | |
4731d4c7 | 2061 | |
60c8aec6 | 2062 | if (parent->role.level == PT_PAGE_TABLE_LEVEL) |
4731d4c7 | 2063 | return 0; |
60c8aec6 MT |
2064 | |
2065 | kvm_mmu_pages_init(parent, &parents, &pages); | |
2066 | while (mmu_unsync_walk(parent, &pages)) { | |
2067 | struct kvm_mmu_page *sp; | |
2068 | ||
2069 | for_each_sp(pages, sp, parents, i) { | |
7775834a | 2070 | kvm_mmu_prepare_zap_page(kvm, sp, invalid_list); |
60c8aec6 | 2071 | mmu_pages_clear_parents(&parents); |
77662e00 | 2072 | zapped++; |
60c8aec6 | 2073 | } |
60c8aec6 MT |
2074 | kvm_mmu_pages_init(parent, &parents, &pages); |
2075 | } | |
2076 | ||
2077 | return zapped; | |
4731d4c7 MT |
2078 | } |
2079 | ||
7775834a XG |
2080 | static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, |
2081 | struct list_head *invalid_list) | |
31aa2b44 | 2082 | { |
4731d4c7 | 2083 | int ret; |
f691fe1d | 2084 | |
7775834a | 2085 | trace_kvm_mmu_prepare_zap_page(sp); |
31aa2b44 | 2086 | ++kvm->stat.mmu_shadow_zapped; |
7775834a | 2087 | ret = mmu_zap_unsync_children(kvm, sp, invalid_list); |
4db35314 | 2088 | kvm_mmu_page_unlink_children(kvm, sp); |
31aa2b44 | 2089 | kvm_mmu_unlink_parents(kvm, sp); |
f6e2c02b | 2090 | if (!sp->role.invalid && !sp->role.direct) |
5b5c6a5a | 2091 | unaccount_shadowed(kvm, sp->gfn); |
4731d4c7 MT |
2092 | if (sp->unsync) |
2093 | kvm_unlink_unsync_page(kvm, sp); | |
4db35314 | 2094 | if (!sp->root_count) { |
54a4f023 GJ |
2095 | /* Count self */ |
2096 | ret++; | |
7775834a | 2097 | list_move(&sp->link, invalid_list); |
aa6bd187 | 2098 | kvm_mod_used_mmu_pages(kvm, -1); |
2e53d63a | 2099 | } else { |
5b5c6a5a | 2100 | list_move(&sp->link, &kvm->arch.active_mmu_pages); |
2e53d63a MT |
2101 | kvm_reload_remote_mmus(kvm); |
2102 | } | |
7775834a XG |
2103 | |
2104 | sp->role.invalid = 1; | |
4731d4c7 | 2105 | return ret; |
a436036b AK |
2106 | } |
2107 | ||
7775834a XG |
2108 | static void kvm_mmu_commit_zap_page(struct kvm *kvm, |
2109 | struct list_head *invalid_list) | |
2110 | { | |
2111 | struct kvm_mmu_page *sp; | |
2112 | ||
2113 | if (list_empty(invalid_list)) | |
2114 | return; | |
2115 | ||
c142786c AK |
2116 | /* |
2117 | * wmb: make sure everyone sees our modifications to the page tables | |
2118 | * rmb: make sure we see changes to vcpu->mode | |
2119 | */ | |
2120 | smp_mb(); | |
4f022648 | 2121 | |
c142786c AK |
2122 | /* |
2123 | * Wait for all vcpus to exit guest mode and/or lockless shadow | |
2124 | * page table walks. | |
2125 | */ | |
2126 | kvm_flush_remote_tlbs(kvm); | |
c2a2ac2b | 2127 | |
7775834a XG |
2128 | do { |
2129 | sp = list_first_entry(invalid_list, struct kvm_mmu_page, link); | |
2130 | WARN_ON(!sp->role.invalid || sp->root_count); | |
bd4c86ea | 2131 | kvm_mmu_isolate_page(sp); |
aa6bd187 | 2132 | kvm_mmu_free_page(sp); |
7775834a | 2133 | } while (!list_empty(invalid_list)); |
7775834a XG |
2134 | } |
2135 | ||
82ce2c96 IE |
2136 | /* |
2137 | * Changing the number of mmu pages allocated to the vm | |
49d5ca26 | 2138 | * Note: if goal_nr_mmu_pages is too small, you will get dead lock |
82ce2c96 | 2139 | */ |
49d5ca26 | 2140 | void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned int goal_nr_mmu_pages) |
82ce2c96 | 2141 | { |
d98ba053 | 2142 | LIST_HEAD(invalid_list); |
82ce2c96 IE |
2143 | /* |
2144 | * If we set the number of mmu pages to be smaller be than the | |
2145 | * number of actived pages , we must to free some mmu pages before we | |
2146 | * change the value | |
2147 | */ | |
2148 | ||
49d5ca26 DH |
2149 | if (kvm->arch.n_used_mmu_pages > goal_nr_mmu_pages) { |
2150 | while (kvm->arch.n_used_mmu_pages > goal_nr_mmu_pages && | |
77662e00 | 2151 | !list_empty(&kvm->arch.active_mmu_pages)) { |
82ce2c96 IE |
2152 | struct kvm_mmu_page *page; |
2153 | ||
f05e70ac | 2154 | page = container_of(kvm->arch.active_mmu_pages.prev, |
82ce2c96 | 2155 | struct kvm_mmu_page, link); |
80b63faf | 2156 | kvm_mmu_prepare_zap_page(kvm, page, &invalid_list); |
82ce2c96 | 2157 | } |
aa6bd187 | 2158 | kvm_mmu_commit_zap_page(kvm, &invalid_list); |
49d5ca26 | 2159 | goal_nr_mmu_pages = kvm->arch.n_used_mmu_pages; |
82ce2c96 | 2160 | } |
82ce2c96 | 2161 | |
49d5ca26 | 2162 | kvm->arch.n_max_mmu_pages = goal_nr_mmu_pages; |
82ce2c96 IE |
2163 | } |
2164 | ||
1cb3f3ae | 2165 | int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn) |
a436036b | 2166 | { |
4db35314 | 2167 | struct kvm_mmu_page *sp; |
f41d335a | 2168 | struct hlist_node *node; |
d98ba053 | 2169 | LIST_HEAD(invalid_list); |
a436036b AK |
2170 | int r; |
2171 | ||
9ad17b10 | 2172 | pgprintk("%s: looking for gfn %llx\n", __func__, gfn); |
a436036b | 2173 | r = 0; |
1cb3f3ae | 2174 | spin_lock(&kvm->mmu_lock); |
f41d335a | 2175 | for_each_gfn_indirect_valid_sp(kvm, sp, gfn, node) { |
9ad17b10 | 2176 | pgprintk("%s: gfn %llx role %x\n", __func__, gfn, |
7ae680eb XG |
2177 | sp->role.word); |
2178 | r = 1; | |
f41d335a | 2179 | kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list); |
7ae680eb | 2180 | } |
d98ba053 | 2181 | kvm_mmu_commit_zap_page(kvm, &invalid_list); |
1cb3f3ae XG |
2182 | spin_unlock(&kvm->mmu_lock); |
2183 | ||
a436036b | 2184 | return r; |
cea0f0e7 | 2185 | } |
1cb3f3ae | 2186 | EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page); |
cea0f0e7 | 2187 | |
38c335f1 | 2188 | static void page_header_update_slot(struct kvm *kvm, void *pte, gfn_t gfn) |
6aa8b732 | 2189 | { |
bc6678a3 | 2190 | int slot = memslot_id(kvm, gfn); |
4db35314 | 2191 | struct kvm_mmu_page *sp = page_header(__pa(pte)); |
6aa8b732 | 2192 | |
291f26bc | 2193 | __set_bit(slot, sp->slot_bitmap); |
6aa8b732 AK |
2194 | } |
2195 | ||
74be52e3 SY |
2196 | /* |
2197 | * The function is based on mtrr_type_lookup() in | |
2198 | * arch/x86/kernel/cpu/mtrr/generic.c | |
2199 | */ | |
2200 | static int get_mtrr_type(struct mtrr_state_type *mtrr_state, | |
2201 | u64 start, u64 end) | |
2202 | { | |
2203 | int i; | |
2204 | u64 base, mask; | |
2205 | u8 prev_match, curr_match; | |
2206 | int num_var_ranges = KVM_NR_VAR_MTRR; | |
2207 | ||
2208 | if (!mtrr_state->enabled) | |
2209 | return 0xFF; | |
2210 | ||
2211 | /* Make end inclusive end, instead of exclusive */ | |
2212 | end--; | |
2213 | ||
2214 | /* Look in fixed ranges. Just return the type as per start */ | |
2215 | if (mtrr_state->have_fixed && (start < 0x100000)) { | |
2216 | int idx; | |
2217 | ||
2218 | if (start < 0x80000) { | |
2219 | idx = 0; | |
2220 | idx += (start >> 16); | |
2221 | return mtrr_state->fixed_ranges[idx]; | |
2222 | } else if (start < 0xC0000) { | |
2223 | idx = 1 * 8; | |
2224 | idx += ((start - 0x80000) >> 14); | |
2225 | return mtrr_state->fixed_ranges[idx]; | |
2226 | } else if (start < 0x1000000) { | |
2227 | idx = 3 * 8; | |
2228 | idx += ((start - 0xC0000) >> 12); | |
2229 | return mtrr_state->fixed_ranges[idx]; | |
2230 | } | |
2231 | } | |
2232 | ||
2233 | /* | |
2234 | * Look in variable ranges | |
2235 | * Look of multiple ranges matching this address and pick type | |
2236 | * as per MTRR precedence | |
2237 | */ | |
2238 | if (!(mtrr_state->enabled & 2)) | |
2239 | return mtrr_state->def_type; | |
2240 | ||
2241 | prev_match = 0xFF; | |
2242 | for (i = 0; i < num_var_ranges; ++i) { | |
2243 | unsigned short start_state, end_state; | |
2244 | ||
2245 | if (!(mtrr_state->var_ranges[i].mask_lo & (1 << 11))) | |
2246 | continue; | |
2247 | ||
2248 | base = (((u64)mtrr_state->var_ranges[i].base_hi) << 32) + | |
2249 | (mtrr_state->var_ranges[i].base_lo & PAGE_MASK); | |
2250 | mask = (((u64)mtrr_state->var_ranges[i].mask_hi) << 32) + | |
2251 | (mtrr_state->var_ranges[i].mask_lo & PAGE_MASK); | |
2252 | ||
2253 | start_state = ((start & mask) == (base & mask)); | |
2254 | end_state = ((end & mask) == (base & mask)); | |
2255 | if (start_state != end_state) | |
2256 | return 0xFE; | |
2257 | ||
2258 | if ((start & mask) != (base & mask)) | |
2259 | continue; | |
2260 | ||
2261 | curr_match = mtrr_state->var_ranges[i].base_lo & 0xff; | |
2262 | if (prev_match == 0xFF) { | |
2263 | prev_match = curr_match; | |
2264 | continue; | |
2265 | } | |
2266 | ||
2267 | if (prev_match == MTRR_TYPE_UNCACHABLE || | |
2268 | curr_match == MTRR_TYPE_UNCACHABLE) | |
2269 | return MTRR_TYPE_UNCACHABLE; | |
2270 | ||
2271 | if ((prev_match == MTRR_TYPE_WRBACK && | |
2272 | curr_match == MTRR_TYPE_WRTHROUGH) || | |
2273 | (prev_match == MTRR_TYPE_WRTHROUGH && | |
2274 | curr_match == MTRR_TYPE_WRBACK)) { | |
2275 | prev_match = MTRR_TYPE_WRTHROUGH; | |
2276 | curr_match = MTRR_TYPE_WRTHROUGH; | |
2277 | } | |
2278 | ||
2279 | if (prev_match != curr_match) | |
2280 | return MTRR_TYPE_UNCACHABLE; | |
2281 | } | |
2282 | ||
2283 | if (prev_match != 0xFF) | |
2284 | return prev_match; | |
2285 | ||
2286 | return mtrr_state->def_type; | |
2287 | } | |
2288 | ||
4b12f0de | 2289 | u8 kvm_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) |
74be52e3 SY |
2290 | { |
2291 | u8 mtrr; | |
2292 | ||
2293 | mtrr = get_mtrr_type(&vcpu->arch.mtrr_state, gfn << PAGE_SHIFT, | |
2294 | (gfn << PAGE_SHIFT) + PAGE_SIZE); | |
2295 | if (mtrr == 0xfe || mtrr == 0xff) | |
2296 | mtrr = MTRR_TYPE_WRBACK; | |
2297 | return mtrr; | |
2298 | } | |
4b12f0de | 2299 | EXPORT_SYMBOL_GPL(kvm_get_guest_memory_type); |
74be52e3 | 2300 | |
9cf5cf5a XG |
2301 | static void __kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) |
2302 | { | |
2303 | trace_kvm_mmu_unsync_page(sp); | |
2304 | ++vcpu->kvm->stat.mmu_unsync; | |
2305 | sp->unsync = 1; | |
2306 | ||
2307 | kvm_mmu_mark_parents_unsync(sp); | |
9cf5cf5a XG |
2308 | } |
2309 | ||
2310 | static void kvm_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn) | |
4731d4c7 | 2311 | { |
4731d4c7 | 2312 | struct kvm_mmu_page *s; |
f41d335a | 2313 | struct hlist_node *node; |
9cf5cf5a | 2314 | |
f41d335a | 2315 | for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node) { |
7ae680eb | 2316 | if (s->unsync) |
4731d4c7 | 2317 | continue; |
9cf5cf5a XG |
2318 | WARN_ON(s->role.level != PT_PAGE_TABLE_LEVEL); |
2319 | __kvm_unsync_page(vcpu, s); | |
4731d4c7 | 2320 | } |
4731d4c7 MT |
2321 | } |
2322 | ||
2323 | static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn, | |
2324 | bool can_unsync) | |
2325 | { | |
9cf5cf5a | 2326 | struct kvm_mmu_page *s; |
f41d335a | 2327 | struct hlist_node *node; |
9cf5cf5a XG |
2328 | bool need_unsync = false; |
2329 | ||
f41d335a | 2330 | for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node) { |
36a2e677 XG |
2331 | if (!can_unsync) |
2332 | return 1; | |
2333 | ||
9cf5cf5a | 2334 | if (s->role.level != PT_PAGE_TABLE_LEVEL) |
4731d4c7 | 2335 | return 1; |
9cf5cf5a XG |
2336 | |
2337 | if (!need_unsync && !s->unsync) { | |
9cf5cf5a XG |
2338 | need_unsync = true; |
2339 | } | |
4731d4c7 | 2340 | } |
9cf5cf5a XG |
2341 | if (need_unsync) |
2342 | kvm_unsync_pages(vcpu, gfn); | |
4731d4c7 MT |
2343 | return 0; |
2344 | } | |
2345 | ||
d555c333 | 2346 | static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, |
1e73f9dd | 2347 | unsigned pte_access, int user_fault, |
640d9b0d | 2348 | int write_fault, int level, |
c2d0ee46 | 2349 | gfn_t gfn, pfn_t pfn, bool speculative, |
9bdbba13 | 2350 | bool can_unsync, bool host_writable) |
1c4f1fd6 | 2351 | { |
6e7d0354 | 2352 | u64 spte; |
1e73f9dd | 2353 | int ret = 0; |
64d4d521 | 2354 | |
ce88decf XG |
2355 | if (set_mmio_spte(sptep, gfn, pfn, pte_access)) |
2356 | return 0; | |
2357 | ||
982c2565 | 2358 | spte = PT_PRESENT_MASK; |
947da538 | 2359 | if (!speculative) |
3201b5d9 | 2360 | spte |= shadow_accessed_mask; |
640d9b0d | 2361 | |
7b52345e SY |
2362 | if (pte_access & ACC_EXEC_MASK) |
2363 | spte |= shadow_x_mask; | |
2364 | else | |
2365 | spte |= shadow_nx_mask; | |
49fde340 | 2366 | |
1c4f1fd6 | 2367 | if (pte_access & ACC_USER_MASK) |
7b52345e | 2368 | spte |= shadow_user_mask; |
49fde340 | 2369 | |
852e3c19 | 2370 | if (level > PT_PAGE_TABLE_LEVEL) |
05da4558 | 2371 | spte |= PT_PAGE_SIZE_MASK; |
b0bc3ee2 | 2372 | if (tdp_enabled) |
4b12f0de SY |
2373 | spte |= kvm_x86_ops->get_mt_mask(vcpu, gfn, |
2374 | kvm_is_mmio_pfn(pfn)); | |
1c4f1fd6 | 2375 | |
9bdbba13 | 2376 | if (host_writable) |
1403283a | 2377 | spte |= SPTE_HOST_WRITEABLE; |
f8e453b0 XG |
2378 | else |
2379 | pte_access &= ~ACC_WRITE_MASK; | |
1403283a | 2380 | |
35149e21 | 2381 | spte |= (u64)pfn << PAGE_SHIFT; |
1c4f1fd6 AK |
2382 | |
2383 | if ((pte_access & ACC_WRITE_MASK) | |
c5a78f2b JR |
2384 | || (!vcpu->arch.mmu.direct_map && write_fault |
2385 | && !is_write_protection(vcpu) && !user_fault)) { | |
1c4f1fd6 | 2386 | |
852e3c19 JR |
2387 | if (level > PT_PAGE_TABLE_LEVEL && |
2388 | has_wrprotected_page(vcpu->kvm, gfn, level)) { | |
38187c83 | 2389 | ret = 1; |
c3707958 | 2390 | drop_spte(vcpu->kvm, sptep); |
be38d276 | 2391 | goto done; |
38187c83 MT |
2392 | } |
2393 | ||
49fde340 | 2394 | spte |= PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE; |
1c4f1fd6 | 2395 | |
c5a78f2b | 2396 | if (!vcpu->arch.mmu.direct_map |
411c588d | 2397 | && !(pte_access & ACC_WRITE_MASK)) { |
69325a12 | 2398 | spte &= ~PT_USER_MASK; |
411c588d AK |
2399 | /* |
2400 | * If we converted a user page to a kernel page, | |
2401 | * so that the kernel can write to it when cr0.wp=0, | |
2402 | * then we should prevent the kernel from executing it | |
2403 | * if SMEP is enabled. | |
2404 | */ | |
2405 | if (kvm_read_cr4_bits(vcpu, X86_CR4_SMEP)) | |
2406 | spte |= PT64_NX_MASK; | |
2407 | } | |
69325a12 | 2408 | |
ecc5589f MT |
2409 | /* |
2410 | * Optimization: for pte sync, if spte was writable the hash | |
2411 | * lookup is unnecessary (and expensive). Write protection | |
2412 | * is responsibility of mmu_get_page / kvm_sync_page. | |
2413 | * Same reasoning can be applied to dirty page accounting. | |
2414 | */ | |
8dae4445 | 2415 | if (!can_unsync && is_writable_pte(*sptep)) |
ecc5589f MT |
2416 | goto set_pte; |
2417 | ||
4731d4c7 | 2418 | if (mmu_need_write_protect(vcpu, gfn, can_unsync)) { |
9ad17b10 | 2419 | pgprintk("%s: found shadow page for %llx, marking ro\n", |
b8688d51 | 2420 | __func__, gfn); |
1e73f9dd | 2421 | ret = 1; |
1c4f1fd6 | 2422 | pte_access &= ~ACC_WRITE_MASK; |
49fde340 | 2423 | spte &= ~(PT_WRITABLE_MASK | SPTE_MMU_WRITEABLE); |
1c4f1fd6 AK |
2424 | } |
2425 | } | |
2426 | ||
1c4f1fd6 AK |
2427 | if (pte_access & ACC_WRITE_MASK) |
2428 | mark_page_dirty(vcpu->kvm, gfn); | |
2429 | ||
38187c83 | 2430 | set_pte: |
6e7d0354 | 2431 | if (mmu_spte_update(sptep, spte)) |
b330aa0c | 2432 | kvm_flush_remote_tlbs(vcpu->kvm); |
be38d276 | 2433 | done: |
1e73f9dd MT |
2434 | return ret; |
2435 | } | |
2436 | ||
d555c333 | 2437 | static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep, |
1e73f9dd | 2438 | unsigned pt_access, unsigned pte_access, |
640d9b0d | 2439 | int user_fault, int write_fault, |
b90a0e6c | 2440 | int *emulate, int level, gfn_t gfn, |
1403283a | 2441 | pfn_t pfn, bool speculative, |
9bdbba13 | 2442 | bool host_writable) |
1e73f9dd MT |
2443 | { |
2444 | int was_rmapped = 0; | |
53a27b39 | 2445 | int rmap_count; |
1e73f9dd MT |
2446 | |
2447 | pgprintk("%s: spte %llx access %x write_fault %d" | |
9ad17b10 | 2448 | " user_fault %d gfn %llx\n", |
d555c333 | 2449 | __func__, *sptep, pt_access, |
1e73f9dd MT |
2450 | write_fault, user_fault, gfn); |
2451 | ||
d555c333 | 2452 | if (is_rmap_spte(*sptep)) { |
1e73f9dd MT |
2453 | /* |
2454 | * If we overwrite a PTE page pointer with a 2MB PMD, unlink | |
2455 | * the parent of the now unreachable PTE. | |
2456 | */ | |
852e3c19 JR |
2457 | if (level > PT_PAGE_TABLE_LEVEL && |
2458 | !is_large_pte(*sptep)) { | |
1e73f9dd | 2459 | struct kvm_mmu_page *child; |
d555c333 | 2460 | u64 pte = *sptep; |
1e73f9dd MT |
2461 | |
2462 | child = page_header(pte & PT64_BASE_ADDR_MASK); | |
bcdd9a93 | 2463 | drop_parent_pte(child, sptep); |
3be2264b | 2464 | kvm_flush_remote_tlbs(vcpu->kvm); |
d555c333 | 2465 | } else if (pfn != spte_to_pfn(*sptep)) { |
9ad17b10 | 2466 | pgprintk("hfn old %llx new %llx\n", |
d555c333 | 2467 | spte_to_pfn(*sptep), pfn); |
c3707958 | 2468 | drop_spte(vcpu->kvm, sptep); |
91546356 | 2469 | kvm_flush_remote_tlbs(vcpu->kvm); |
6bed6b9e JR |
2470 | } else |
2471 | was_rmapped = 1; | |
1e73f9dd | 2472 | } |
852e3c19 | 2473 | |
d555c333 | 2474 | if (set_spte(vcpu, sptep, pte_access, user_fault, write_fault, |
640d9b0d | 2475 | level, gfn, pfn, speculative, true, |
9bdbba13 | 2476 | host_writable)) { |
1e73f9dd | 2477 | if (write_fault) |
b90a0e6c | 2478 | *emulate = 1; |
5304efde | 2479 | kvm_mmu_flush_tlb(vcpu); |
a378b4e6 | 2480 | } |
1e73f9dd | 2481 | |
ce88decf XG |
2482 | if (unlikely(is_mmio_spte(*sptep) && emulate)) |
2483 | *emulate = 1; | |
2484 | ||
d555c333 | 2485 | pgprintk("%s: setting spte %llx\n", __func__, *sptep); |
9ad17b10 | 2486 | pgprintk("instantiating %s PTE (%s) at %llx (%llx) addr %p\n", |
d555c333 | 2487 | is_large_pte(*sptep)? "2MB" : "4kB", |
a205bc19 JR |
2488 | *sptep & PT_PRESENT_MASK ?"RW":"R", gfn, |
2489 | *sptep, sptep); | |
d555c333 | 2490 | if (!was_rmapped && is_large_pte(*sptep)) |
05da4558 MT |
2491 | ++vcpu->kvm->stat.lpages; |
2492 | ||
ffb61bb3 XG |
2493 | if (is_shadow_present_pte(*sptep)) { |
2494 | page_header_update_slot(vcpu->kvm, sptep, gfn); | |
2495 | if (!was_rmapped) { | |
2496 | rmap_count = rmap_add(vcpu, sptep, gfn); | |
2497 | if (rmap_count > RMAP_RECYCLE_THRESHOLD) | |
2498 | rmap_recycle(vcpu, sptep, gfn); | |
2499 | } | |
1c4f1fd6 | 2500 | } |
9ed5520d | 2501 | kvm_release_pfn_clean(pfn); |
1c4f1fd6 AK |
2502 | } |
2503 | ||
6aa8b732 AK |
2504 | static void nonpaging_new_cr3(struct kvm_vcpu *vcpu) |
2505 | { | |
e676505a | 2506 | mmu_free_roots(vcpu); |
6aa8b732 AK |
2507 | } |
2508 | ||
957ed9ef XG |
2509 | static pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, |
2510 | bool no_dirty_log) | |
2511 | { | |
2512 | struct kvm_memory_slot *slot; | |
2513 | unsigned long hva; | |
2514 | ||
5d163b1c | 2515 | slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log); |
957ed9ef | 2516 | if (!slot) { |
fce92dce XG |
2517 | get_page(fault_page); |
2518 | return page_to_pfn(fault_page); | |
957ed9ef XG |
2519 | } |
2520 | ||
2521 | hva = gfn_to_hva_memslot(slot, gfn); | |
2522 | ||
2523 | return hva_to_pfn_atomic(vcpu->kvm, hva); | |
2524 | } | |
2525 | ||
2526 | static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu, | |
2527 | struct kvm_mmu_page *sp, | |
2528 | u64 *start, u64 *end) | |
2529 | { | |
2530 | struct page *pages[PTE_PREFETCH_NUM]; | |
2531 | unsigned access = sp->role.access; | |
2532 | int i, ret; | |
2533 | gfn_t gfn; | |
2534 | ||
2535 | gfn = kvm_mmu_page_get_gfn(sp, start - sp->spt); | |
5d163b1c | 2536 | if (!gfn_to_memslot_dirty_bitmap(vcpu, gfn, access & ACC_WRITE_MASK)) |
957ed9ef XG |
2537 | return -1; |
2538 | ||
2539 | ret = gfn_to_page_many_atomic(vcpu->kvm, gfn, pages, end - start); | |
2540 | if (ret <= 0) | |
2541 | return -1; | |
2542 | ||
2543 | for (i = 0; i < ret; i++, gfn++, start++) | |
2544 | mmu_set_spte(vcpu, start, ACC_ALL, | |
640d9b0d | 2545 | access, 0, 0, NULL, |
957ed9ef XG |
2546 | sp->role.level, gfn, |
2547 | page_to_pfn(pages[i]), true, true); | |
2548 | ||
2549 | return 0; | |
2550 | } | |
2551 | ||
2552 | static void __direct_pte_prefetch(struct kvm_vcpu *vcpu, | |
2553 | struct kvm_mmu_page *sp, u64 *sptep) | |
2554 | { | |
2555 | u64 *spte, *start = NULL; | |
2556 | int i; | |
2557 | ||
2558 | WARN_ON(!sp->role.direct); | |
2559 | ||
2560 | i = (sptep - sp->spt) & ~(PTE_PREFETCH_NUM - 1); | |
2561 | spte = sp->spt + i; | |
2562 | ||
2563 | for (i = 0; i < PTE_PREFETCH_NUM; i++, spte++) { | |
c3707958 | 2564 | if (is_shadow_present_pte(*spte) || spte == sptep) { |
957ed9ef XG |
2565 | if (!start) |
2566 | continue; | |
2567 | if (direct_pte_prefetch_many(vcpu, sp, start, spte) < 0) | |
2568 | break; | |
2569 | start = NULL; | |
2570 | } else if (!start) | |
2571 | start = spte; | |
2572 | } | |
2573 | } | |
2574 | ||
2575 | static void direct_pte_prefetch(struct kvm_vcpu *vcpu, u64 *sptep) | |
2576 | { | |
2577 | struct kvm_mmu_page *sp; | |
2578 | ||
2579 | /* | |
2580 | * Since it's no accessed bit on EPT, it's no way to | |
2581 | * distinguish between actually accessed translations | |
2582 | * and prefetched, so disable pte prefetch if EPT is | |
2583 | * enabled. | |
2584 | */ | |
2585 | if (!shadow_accessed_mask) | |
2586 | return; | |
2587 | ||
2588 | sp = page_header(__pa(sptep)); | |
2589 | if (sp->role.level > PT_PAGE_TABLE_LEVEL) | |
2590 | return; | |
2591 | ||
2592 | __direct_pte_prefetch(vcpu, sp, sptep); | |
2593 | } | |
2594 | ||
9f652d21 | 2595 | static int __direct_map(struct kvm_vcpu *vcpu, gpa_t v, int write, |
2ec4739d XG |
2596 | int map_writable, int level, gfn_t gfn, pfn_t pfn, |
2597 | bool prefault) | |
140754bc | 2598 | { |
9f652d21 | 2599 | struct kvm_shadow_walk_iterator iterator; |
140754bc | 2600 | struct kvm_mmu_page *sp; |
b90a0e6c | 2601 | int emulate = 0; |
140754bc | 2602 | gfn_t pseudo_gfn; |
6aa8b732 | 2603 | |
9f652d21 | 2604 | for_each_shadow_entry(vcpu, (u64)gfn << PAGE_SHIFT, iterator) { |
852e3c19 | 2605 | if (iterator.level == level) { |
612819c3 MT |
2606 | unsigned pte_access = ACC_ALL; |
2607 | ||
612819c3 | 2608 | mmu_set_spte(vcpu, iterator.sptep, ACC_ALL, pte_access, |
b90a0e6c | 2609 | 0, write, &emulate, |
2ec4739d | 2610 | level, gfn, pfn, prefault, map_writable); |
957ed9ef | 2611 | direct_pte_prefetch(vcpu, iterator.sptep); |
9f652d21 AK |
2612 | ++vcpu->stat.pf_fixed; |
2613 | break; | |
6aa8b732 AK |
2614 | } |
2615 | ||
c3707958 | 2616 | if (!is_shadow_present_pte(*iterator.sptep)) { |
c9fa0b3b LJ |
2617 | u64 base_addr = iterator.addr; |
2618 | ||
2619 | base_addr &= PT64_LVL_ADDR_MASK(iterator.level); | |
2620 | pseudo_gfn = base_addr >> PAGE_SHIFT; | |
9f652d21 AK |
2621 | sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr, |
2622 | iterator.level - 1, | |
2623 | 1, ACC_ALL, iterator.sptep); | |
2624 | if (!sp) { | |
2625 | pgprintk("nonpaging_map: ENOMEM\n"); | |
2626 | kvm_release_pfn_clean(pfn); | |
2627 | return -ENOMEM; | |
2628 | } | |
140754bc | 2629 | |
1df9f2dc XG |
2630 | mmu_spte_set(iterator.sptep, |
2631 | __pa(sp->spt) | |
2632 | | PT_PRESENT_MASK | PT_WRITABLE_MASK | |
2633 | | shadow_user_mask | shadow_x_mask | |
2634 | | shadow_accessed_mask); | |
9f652d21 AK |
2635 | } |
2636 | } | |
b90a0e6c | 2637 | return emulate; |
6aa8b732 AK |
2638 | } |
2639 | ||
77db5cbd | 2640 | static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *tsk) |
bf998156 | 2641 | { |
77db5cbd HY |
2642 | siginfo_t info; |
2643 | ||
2644 | info.si_signo = SIGBUS; | |
2645 | info.si_errno = 0; | |
2646 | info.si_code = BUS_MCEERR_AR; | |
2647 | info.si_addr = (void __user *)address; | |
2648 | info.si_addr_lsb = PAGE_SHIFT; | |
bf998156 | 2649 | |
77db5cbd | 2650 | send_sig_info(SIGBUS, &info, tsk); |
bf998156 HY |
2651 | } |
2652 | ||
d7c55201 | 2653 | static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, pfn_t pfn) |
bf998156 HY |
2654 | { |
2655 | kvm_release_pfn_clean(pfn); | |
2656 | if (is_hwpoison_pfn(pfn)) { | |
bebb106a | 2657 | kvm_send_hwpoison_signal(gfn_to_hva(vcpu->kvm, gfn), current); |
bf998156 | 2658 | return 0; |
d7c55201 | 2659 | } |
edba23e5 | 2660 | |
d7c55201 | 2661 | return -EFAULT; |
bf998156 HY |
2662 | } |
2663 | ||
936a5fe6 AA |
2664 | static void transparent_hugepage_adjust(struct kvm_vcpu *vcpu, |
2665 | gfn_t *gfnp, pfn_t *pfnp, int *levelp) | |
2666 | { | |
2667 | pfn_t pfn = *pfnp; | |
2668 | gfn_t gfn = *gfnp; | |
2669 | int level = *levelp; | |
2670 | ||
2671 | /* | |
2672 | * Check if it's a transparent hugepage. If this would be an | |
2673 | * hugetlbfs page, level wouldn't be set to | |
2674 | * PT_PAGE_TABLE_LEVEL and there would be no adjustment done | |
2675 | * here. | |
2676 | */ | |
2677 | if (!is_error_pfn(pfn) && !kvm_is_mmio_pfn(pfn) && | |
2678 | level == PT_PAGE_TABLE_LEVEL && | |
2679 | PageTransCompound(pfn_to_page(pfn)) && | |
2680 | !has_wrprotected_page(vcpu->kvm, gfn, PT_DIRECTORY_LEVEL)) { | |
2681 | unsigned long mask; | |
2682 | /* | |
2683 | * mmu_notifier_retry was successful and we hold the | |
2684 | * mmu_lock here, so the pmd can't become splitting | |
2685 | * from under us, and in turn | |
2686 | * __split_huge_page_refcount() can't run from under | |
2687 | * us and we can safely transfer the refcount from | |
2688 | * PG_tail to PG_head as we switch the pfn to tail to | |
2689 | * head. | |
2690 | */ | |
2691 | *levelp = level = PT_DIRECTORY_LEVEL; | |
2692 | mask = KVM_PAGES_PER_HPAGE(level) - 1; | |
2693 | VM_BUG_ON((gfn & mask) != (pfn & mask)); | |
2694 | if (pfn & mask) { | |
2695 | gfn &= ~mask; | |
2696 | *gfnp = gfn; | |
2697 | kvm_release_pfn_clean(pfn); | |
2698 | pfn &= ~mask; | |
c3586667 | 2699 | kvm_get_pfn(pfn); |
936a5fe6 AA |
2700 | *pfnp = pfn; |
2701 | } | |
2702 | } | |
2703 | } | |
2704 | ||
d7c55201 XG |
2705 | static bool mmu_invalid_pfn(pfn_t pfn) |
2706 | { | |
ce88decf | 2707 | return unlikely(is_invalid_pfn(pfn)); |
d7c55201 XG |
2708 | } |
2709 | ||
2710 | static bool handle_abnormal_pfn(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, | |
2711 | pfn_t pfn, unsigned access, int *ret_val) | |
2712 | { | |
2713 | bool ret = true; | |
2714 | ||
2715 | /* The pfn is invalid, report the error! */ | |
2716 | if (unlikely(is_invalid_pfn(pfn))) { | |
2717 | *ret_val = kvm_handle_bad_page(vcpu, gfn, pfn); | |
2718 | goto exit; | |
2719 | } | |
2720 | ||
ce88decf | 2721 | if (unlikely(is_noslot_pfn(pfn))) |
d7c55201 | 2722 | vcpu_cache_mmio_info(vcpu, gva, gfn, access); |
d7c55201 XG |
2723 | |
2724 | ret = false; | |
2725 | exit: | |
2726 | return ret; | |
2727 | } | |
2728 | ||
c7ba5b48 XG |
2729 | static bool page_fault_can_be_fast(struct kvm_vcpu *vcpu, u32 error_code) |
2730 | { | |
2731 | /* | |
2732 | * #PF can be fast only if the shadow page table is present and it | |
2733 | * is caused by write-protect, that means we just need change the | |
2734 | * W bit of the spte which can be done out of mmu-lock. | |
2735 | */ | |
2736 | if (!(error_code & PFERR_PRESENT_MASK) || | |
2737 | !(error_code & PFERR_WRITE_MASK)) | |
2738 | return false; | |
2739 | ||
2740 | return true; | |
2741 | } | |
2742 | ||
2743 | static bool | |
2744 | fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 spte) | |
2745 | { | |
2746 | struct kvm_mmu_page *sp = page_header(__pa(sptep)); | |
2747 | gfn_t gfn; | |
2748 | ||
2749 | WARN_ON(!sp->role.direct); | |
2750 | ||
2751 | /* | |
2752 | * The gfn of direct spte is stable since it is calculated | |
2753 | * by sp->gfn. | |
2754 | */ | |
2755 | gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); | |
2756 | ||
2757 | if (cmpxchg64(sptep, spte, spte | PT_WRITABLE_MASK) == spte) | |
2758 | mark_page_dirty(vcpu->kvm, gfn); | |
2759 | ||
2760 | return true; | |
2761 | } | |
2762 | ||
2763 | /* | |
2764 | * Return value: | |
2765 | * - true: let the vcpu to access on the same address again. | |
2766 | * - false: let the real page fault path to fix it. | |
2767 | */ | |
2768 | static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level, | |
2769 | u32 error_code) | |
2770 | { | |
2771 | struct kvm_shadow_walk_iterator iterator; | |
2772 | bool ret = false; | |
2773 | u64 spte = 0ull; | |
2774 | ||
2775 | if (!page_fault_can_be_fast(vcpu, error_code)) | |
2776 | return false; | |
2777 | ||
2778 | walk_shadow_page_lockless_begin(vcpu); | |
2779 | for_each_shadow_entry_lockless(vcpu, gva, iterator, spte) | |
2780 | if (!is_shadow_present_pte(spte) || iterator.level < level) | |
2781 | break; | |
2782 | ||
2783 | /* | |
2784 | * If the mapping has been changed, let the vcpu fault on the | |
2785 | * same address again. | |
2786 | */ | |
2787 | if (!is_rmap_spte(spte)) { | |
2788 | ret = true; | |
2789 | goto exit; | |
2790 | } | |
2791 | ||
2792 | if (!is_last_spte(spte, level)) | |
2793 | goto exit; | |
2794 | ||
2795 | /* | |
2796 | * Check if it is a spurious fault caused by TLB lazily flushed. | |
2797 | * | |
2798 | * Need not check the access of upper level table entries since | |
2799 | * they are always ACC_ALL. | |
2800 | */ | |
2801 | if (is_writable_pte(spte)) { | |
2802 | ret = true; | |
2803 | goto exit; | |
2804 | } | |
2805 | ||
2806 | /* | |
2807 | * Currently, to simplify the code, only the spte write-protected | |
2808 | * by dirty-log can be fast fixed. | |
2809 | */ | |
2810 | if (!spte_is_locklessly_modifiable(spte)) | |
2811 | goto exit; | |
2812 | ||
2813 | /* | |
2814 | * Currently, fast page fault only works for direct mapping since | |
2815 | * the gfn is not stable for indirect shadow page. | |
2816 | * See Documentation/virtual/kvm/locking.txt to get more detail. | |
2817 | */ | |
2818 | ret = fast_pf_fix_direct_spte(vcpu, iterator.sptep, spte); | |
2819 | exit: | |
a72faf25 XG |
2820 | trace_fast_page_fault(vcpu, gva, error_code, iterator.sptep, |
2821 | spte, ret); | |
c7ba5b48 XG |
2822 | walk_shadow_page_lockless_end(vcpu); |
2823 | ||
2824 | return ret; | |
2825 | } | |
2826 | ||
78b2c54a | 2827 | static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, |
060c2abe XG |
2828 | gva_t gva, pfn_t *pfn, bool write, bool *writable); |
2829 | ||
c7ba5b48 XG |
2830 | static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, |
2831 | gfn_t gfn, bool prefault) | |
10589a46 MT |
2832 | { |
2833 | int r; | |
852e3c19 | 2834 | int level; |
936a5fe6 | 2835 | int force_pt_level; |
35149e21 | 2836 | pfn_t pfn; |
e930bffe | 2837 | unsigned long mmu_seq; |
c7ba5b48 | 2838 | bool map_writable, write = error_code & PFERR_WRITE_MASK; |
aaee2c94 | 2839 | |
936a5fe6 AA |
2840 | force_pt_level = mapping_level_dirty_bitmap(vcpu, gfn); |
2841 | if (likely(!force_pt_level)) { | |
2842 | level = mapping_level(vcpu, gfn); | |
2843 | /* | |
2844 | * This path builds a PAE pagetable - so we can map | |
2845 | * 2mb pages at maximum. Therefore check if the level | |
2846 | * is larger than that. | |
2847 | */ | |
2848 | if (level > PT_DIRECTORY_LEVEL) | |
2849 | level = PT_DIRECTORY_LEVEL; | |
852e3c19 | 2850 | |
936a5fe6 AA |
2851 | gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); |
2852 | } else | |
2853 | level = PT_PAGE_TABLE_LEVEL; | |
05da4558 | 2854 | |
c7ba5b48 XG |
2855 | if (fast_page_fault(vcpu, v, level, error_code)) |
2856 | return 0; | |
2857 | ||
e930bffe | 2858 | mmu_seq = vcpu->kvm->mmu_notifier_seq; |
4c2155ce | 2859 | smp_rmb(); |
060c2abe | 2860 | |
78b2c54a | 2861 | if (try_async_pf(vcpu, prefault, gfn, v, &pfn, write, &map_writable)) |
060c2abe | 2862 | return 0; |
aaee2c94 | 2863 | |
d7c55201 XG |
2864 | if (handle_abnormal_pfn(vcpu, v, gfn, pfn, ACC_ALL, &r)) |
2865 | return r; | |
d196e343 | 2866 | |
aaee2c94 | 2867 | spin_lock(&vcpu->kvm->mmu_lock); |
e930bffe AA |
2868 | if (mmu_notifier_retry(vcpu, mmu_seq)) |
2869 | goto out_unlock; | |
eb787d10 | 2870 | kvm_mmu_free_some_pages(vcpu); |
936a5fe6 AA |
2871 | if (likely(!force_pt_level)) |
2872 | transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level); | |
2ec4739d XG |
2873 | r = __direct_map(vcpu, v, write, map_writable, level, gfn, pfn, |
2874 | prefault); | |
aaee2c94 MT |
2875 | spin_unlock(&vcpu->kvm->mmu_lock); |
2876 | ||
aaee2c94 | 2877 | |
10589a46 | 2878 | return r; |
e930bffe AA |
2879 | |
2880 | out_unlock: | |
2881 | spin_unlock(&vcpu->kvm->mmu_lock); | |
2882 | kvm_release_pfn_clean(pfn); | |
2883 | return 0; | |
10589a46 MT |
2884 | } |
2885 | ||
2886 | ||
17ac10ad AK |
2887 | static void mmu_free_roots(struct kvm_vcpu *vcpu) |
2888 | { | |
2889 | int i; | |
4db35314 | 2890 | struct kvm_mmu_page *sp; |
d98ba053 | 2891 | LIST_HEAD(invalid_list); |
17ac10ad | 2892 | |
ad312c7c | 2893 | if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) |
7b53aa56 | 2894 | return; |
aaee2c94 | 2895 | spin_lock(&vcpu->kvm->mmu_lock); |
81407ca5 JR |
2896 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL && |
2897 | (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL || | |
2898 | vcpu->arch.mmu.direct_map)) { | |
ad312c7c | 2899 | hpa_t root = vcpu->arch.mmu.root_hpa; |
17ac10ad | 2900 | |
4db35314 AK |
2901 | sp = page_header(root); |
2902 | --sp->root_count; | |
d98ba053 XG |
2903 | if (!sp->root_count && sp->role.invalid) { |
2904 | kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list); | |
2905 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); | |
2906 | } | |
ad312c7c | 2907 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
aaee2c94 | 2908 | spin_unlock(&vcpu->kvm->mmu_lock); |
17ac10ad AK |
2909 | return; |
2910 | } | |
17ac10ad | 2911 | for (i = 0; i < 4; ++i) { |
ad312c7c | 2912 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad | 2913 | |
417726a3 | 2914 | if (root) { |
417726a3 | 2915 | root &= PT64_BASE_ADDR_MASK; |
4db35314 AK |
2916 | sp = page_header(root); |
2917 | --sp->root_count; | |
2e53d63a | 2918 | if (!sp->root_count && sp->role.invalid) |
d98ba053 XG |
2919 | kvm_mmu_prepare_zap_page(vcpu->kvm, sp, |
2920 | &invalid_list); | |
417726a3 | 2921 | } |
ad312c7c | 2922 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 2923 | } |
d98ba053 | 2924 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
aaee2c94 | 2925 | spin_unlock(&vcpu->kvm->mmu_lock); |
ad312c7c | 2926 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; |
17ac10ad AK |
2927 | } |
2928 | ||
8986ecc0 MT |
2929 | static int mmu_check_root(struct kvm_vcpu *vcpu, gfn_t root_gfn) |
2930 | { | |
2931 | int ret = 0; | |
2932 | ||
2933 | if (!kvm_is_visible_gfn(vcpu->kvm, root_gfn)) { | |
a8eeb04a | 2934 | kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); |
8986ecc0 MT |
2935 | ret = 1; |
2936 | } | |
2937 | ||
2938 | return ret; | |
2939 | } | |
2940 | ||
651dd37a JR |
2941 | static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) |
2942 | { | |
2943 | struct kvm_mmu_page *sp; | |
7ebaf15e | 2944 | unsigned i; |
651dd37a JR |
2945 | |
2946 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { | |
2947 | spin_lock(&vcpu->kvm->mmu_lock); | |
2948 | kvm_mmu_free_some_pages(vcpu); | |
2949 | sp = kvm_mmu_get_page(vcpu, 0, 0, PT64_ROOT_LEVEL, | |
2950 | 1, ACC_ALL, NULL); | |
2951 | ++sp->root_count; | |
2952 | spin_unlock(&vcpu->kvm->mmu_lock); | |
2953 | vcpu->arch.mmu.root_hpa = __pa(sp->spt); | |
2954 | } else if (vcpu->arch.mmu.shadow_root_level == PT32E_ROOT_LEVEL) { | |
2955 | for (i = 0; i < 4; ++i) { | |
2956 | hpa_t root = vcpu->arch.mmu.pae_root[i]; | |
2957 | ||
2958 | ASSERT(!VALID_PAGE(root)); | |
2959 | spin_lock(&vcpu->kvm->mmu_lock); | |
2960 | kvm_mmu_free_some_pages(vcpu); | |
649497d1 AK |
2961 | sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT), |
2962 | i << 30, | |
651dd37a JR |
2963 | PT32_ROOT_LEVEL, 1, ACC_ALL, |
2964 | NULL); | |
2965 | root = __pa(sp->spt); | |
2966 | ++sp->root_count; | |
2967 | spin_unlock(&vcpu->kvm->mmu_lock); | |
2968 | vcpu->arch.mmu.pae_root[i] = root | PT_PRESENT_MASK; | |
651dd37a | 2969 | } |
6292757f | 2970 | vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); |
651dd37a JR |
2971 | } else |
2972 | BUG(); | |
2973 | ||
2974 | return 0; | |
2975 | } | |
2976 | ||
2977 | static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) | |
17ac10ad | 2978 | { |
4db35314 | 2979 | struct kvm_mmu_page *sp; |
81407ca5 JR |
2980 | u64 pdptr, pm_mask; |
2981 | gfn_t root_gfn; | |
2982 | int i; | |
3bb65a22 | 2983 | |
5777ed34 | 2984 | root_gfn = vcpu->arch.mmu.get_cr3(vcpu) >> PAGE_SHIFT; |
17ac10ad | 2985 | |
651dd37a JR |
2986 | if (mmu_check_root(vcpu, root_gfn)) |
2987 | return 1; | |
2988 | ||
2989 | /* | |
2990 | * Do we shadow a long mode page table? If so we need to | |
2991 | * write-protect the guests page table root. | |
2992 | */ | |
2993 | if (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL) { | |
ad312c7c | 2994 | hpa_t root = vcpu->arch.mmu.root_hpa; |
17ac10ad AK |
2995 | |
2996 | ASSERT(!VALID_PAGE(root)); | |
651dd37a | 2997 | |
8facbbff | 2998 | spin_lock(&vcpu->kvm->mmu_lock); |
24955b6c | 2999 | kvm_mmu_free_some_pages(vcpu); |
651dd37a JR |
3000 | sp = kvm_mmu_get_page(vcpu, root_gfn, 0, PT64_ROOT_LEVEL, |
3001 | 0, ACC_ALL, NULL); | |
4db35314 AK |
3002 | root = __pa(sp->spt); |
3003 | ++sp->root_count; | |
8facbbff | 3004 | spin_unlock(&vcpu->kvm->mmu_lock); |
ad312c7c | 3005 | vcpu->arch.mmu.root_hpa = root; |
8986ecc0 | 3006 | return 0; |
17ac10ad | 3007 | } |
f87f9288 | 3008 | |
651dd37a JR |
3009 | /* |
3010 | * We shadow a 32 bit page table. This may be a legacy 2-level | |
81407ca5 JR |
3011 | * or a PAE 3-level page table. In either case we need to be aware that |
3012 | * the shadow page table may be a PAE or a long mode page table. | |
651dd37a | 3013 | */ |
81407ca5 JR |
3014 | pm_mask = PT_PRESENT_MASK; |
3015 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) | |
3016 | pm_mask |= PT_ACCESSED_MASK | PT_WRITABLE_MASK | PT_USER_MASK; | |
3017 | ||
17ac10ad | 3018 | for (i = 0; i < 4; ++i) { |
ad312c7c | 3019 | hpa_t root = vcpu->arch.mmu.pae_root[i]; |
17ac10ad AK |
3020 | |
3021 | ASSERT(!VALID_PAGE(root)); | |
ad312c7c | 3022 | if (vcpu->arch.mmu.root_level == PT32E_ROOT_LEVEL) { |
e4e517b4 | 3023 | pdptr = vcpu->arch.mmu.get_pdptr(vcpu, i); |
43a3795a | 3024 | if (!is_present_gpte(pdptr)) { |
ad312c7c | 3025 | vcpu->arch.mmu.pae_root[i] = 0; |
417726a3 AK |
3026 | continue; |
3027 | } | |
6de4f3ad | 3028 | root_gfn = pdptr >> PAGE_SHIFT; |
f87f9288 JR |
3029 | if (mmu_check_root(vcpu, root_gfn)) |
3030 | return 1; | |
5a7388c2 | 3031 | } |
8facbbff | 3032 | spin_lock(&vcpu->kvm->mmu_lock); |
24955b6c | 3033 | kvm_mmu_free_some_pages(vcpu); |
4db35314 | 3034 | sp = kvm_mmu_get_page(vcpu, root_gfn, i << 30, |
651dd37a | 3035 | PT32_ROOT_LEVEL, 0, |
f7d9c7b7 | 3036 | ACC_ALL, NULL); |
4db35314 AK |
3037 | root = __pa(sp->spt); |
3038 | ++sp->root_count; | |
8facbbff AK |
3039 | spin_unlock(&vcpu->kvm->mmu_lock); |
3040 | ||
81407ca5 | 3041 | vcpu->arch.mmu.pae_root[i] = root | pm_mask; |
17ac10ad | 3042 | } |
6292757f | 3043 | vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.pae_root); |
81407ca5 JR |
3044 | |
3045 | /* | |
3046 | * If we shadow a 32 bit page table with a long mode page | |
3047 | * table we enter this path. | |
3048 | */ | |
3049 | if (vcpu->arch.mmu.shadow_root_level == PT64_ROOT_LEVEL) { | |
3050 | if (vcpu->arch.mmu.lm_root == NULL) { | |
3051 | /* | |
3052 | * The additional page necessary for this is only | |
3053 | * allocated on demand. | |
3054 | */ | |
3055 | ||
3056 | u64 *lm_root; | |
3057 | ||
3058 | lm_root = (void*)get_zeroed_page(GFP_KERNEL); | |
3059 | if (lm_root == NULL) | |
3060 | return 1; | |
3061 | ||
3062 | lm_root[0] = __pa(vcpu->arch.mmu.pae_root) | pm_mask; | |
3063 | ||
3064 | vcpu->arch.mmu.lm_root = lm_root; | |
3065 | } | |
3066 | ||
3067 | vcpu->arch.mmu.root_hpa = __pa(vcpu->arch.mmu.lm_root); | |
3068 | } | |
3069 | ||
8986ecc0 | 3070 | return 0; |
17ac10ad AK |
3071 | } |
3072 | ||
651dd37a JR |
3073 | static int mmu_alloc_roots(struct kvm_vcpu *vcpu) |
3074 | { | |
3075 | if (vcpu->arch.mmu.direct_map) | |
3076 | return mmu_alloc_direct_roots(vcpu); | |
3077 | else | |
3078 | return mmu_alloc_shadow_roots(vcpu); | |
3079 | } | |
3080 | ||
0ba73cda MT |
3081 | static void mmu_sync_roots(struct kvm_vcpu *vcpu) |
3082 | { | |
3083 | int i; | |
3084 | struct kvm_mmu_page *sp; | |
3085 | ||
81407ca5 JR |
3086 | if (vcpu->arch.mmu.direct_map) |
3087 | return; | |
3088 | ||
0ba73cda MT |
3089 | if (!VALID_PAGE(vcpu->arch.mmu.root_hpa)) |
3090 | return; | |
6903074c | 3091 | |
bebb106a | 3092 | vcpu_clear_mmio_info(vcpu, ~0ul); |
0375f7fa | 3093 | kvm_mmu_audit(vcpu, AUDIT_PRE_SYNC); |
81407ca5 | 3094 | if (vcpu->arch.mmu.root_level == PT64_ROOT_LEVEL) { |
0ba73cda MT |
3095 | hpa_t root = vcpu->arch.mmu.root_hpa; |
3096 | sp = page_header(root); | |
3097 | mmu_sync_children(vcpu, sp); | |
0375f7fa | 3098 | kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); |
0ba73cda MT |
3099 | return; |
3100 | } | |
3101 | for (i = 0; i < 4; ++i) { | |
3102 | hpa_t root = vcpu->arch.mmu.pae_root[i]; | |
3103 | ||
8986ecc0 | 3104 | if (root && VALID_PAGE(root)) { |
0ba73cda MT |
3105 | root &= PT64_BASE_ADDR_MASK; |
3106 | sp = page_header(root); | |
3107 | mmu_sync_children(vcpu, sp); | |
3108 | } | |
3109 | } | |
0375f7fa | 3110 | kvm_mmu_audit(vcpu, AUDIT_POST_SYNC); |
0ba73cda MT |
3111 | } |
3112 | ||
3113 | void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu) | |
3114 | { | |
3115 | spin_lock(&vcpu->kvm->mmu_lock); | |
3116 | mmu_sync_roots(vcpu); | |
6cffe8ca | 3117 | spin_unlock(&vcpu->kvm->mmu_lock); |
0ba73cda MT |
3118 | } |
3119 | ||
1871c602 | 3120 | static gpa_t nonpaging_gva_to_gpa(struct kvm_vcpu *vcpu, gva_t vaddr, |
ab9ae313 | 3121 | u32 access, struct x86_exception *exception) |
6aa8b732 | 3122 | { |
ab9ae313 AK |
3123 | if (exception) |
3124 | exception->error_code = 0; | |
6aa8b732 AK |
3125 | return vaddr; |
3126 | } | |
3127 | ||
6539e738 | 3128 | static gpa_t nonpaging_gva_to_gpa_nested(struct kvm_vcpu *vcpu, gva_t vaddr, |
ab9ae313 AK |
3129 | u32 access, |
3130 | struct x86_exception *exception) | |
6539e738 | 3131 | { |
ab9ae313 AK |
3132 | if (exception) |
3133 | exception->error_code = 0; | |
6539e738 JR |
3134 | return vcpu->arch.nested_mmu.translate_gpa(vcpu, vaddr, access); |
3135 | } | |
3136 | ||
ce88decf XG |
3137 | static bool quickly_check_mmio_pf(struct kvm_vcpu *vcpu, u64 addr, bool direct) |
3138 | { | |
3139 | if (direct) | |
3140 | return vcpu_match_mmio_gpa(vcpu, addr); | |
3141 | ||
3142 | return vcpu_match_mmio_gva(vcpu, addr); | |
3143 | } | |
3144 | ||
3145 | ||
3146 | /* | |
3147 | * On direct hosts, the last spte is only allows two states | |
3148 | * for mmio page fault: | |
3149 | * - It is the mmio spte | |
3150 | * - It is zapped or it is being zapped. | |
3151 | * | |
3152 | * This function completely checks the spte when the last spte | |
3153 | * is not the mmio spte. | |
3154 | */ | |
3155 | static bool check_direct_spte_mmio_pf(u64 spte) | |
3156 | { | |
3157 | return __check_direct_spte_mmio_pf(spte); | |
3158 | } | |
3159 | ||
3160 | static u64 walk_shadow_page_get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr) | |
3161 | { | |
3162 | struct kvm_shadow_walk_iterator iterator; | |
3163 | u64 spte = 0ull; | |
3164 | ||
3165 | walk_shadow_page_lockless_begin(vcpu); | |
3166 | for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) | |
3167 | if (!is_shadow_present_pte(spte)) | |
3168 | break; | |
3169 | walk_shadow_page_lockless_end(vcpu); | |
3170 | ||
3171 | return spte; | |
3172 | } | |
3173 | ||
3174 | /* | |
3175 | * If it is a real mmio page fault, return 1 and emulat the instruction | |
3176 | * directly, return 0 to let CPU fault again on the address, -1 is | |
3177 | * returned if bug is detected. | |
3178 | */ | |
3179 | int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) | |
3180 | { | |
3181 | u64 spte; | |
3182 | ||
3183 | if (quickly_check_mmio_pf(vcpu, addr, direct)) | |
3184 | return 1; | |
3185 | ||
3186 | spte = walk_shadow_page_get_mmio_spte(vcpu, addr); | |
3187 | ||
3188 | if (is_mmio_spte(spte)) { | |
3189 | gfn_t gfn = get_mmio_spte_gfn(spte); | |
3190 | unsigned access = get_mmio_spte_access(spte); | |
3191 | ||
3192 | if (direct) | |
3193 | addr = 0; | |
4f022648 XG |
3194 | |
3195 | trace_handle_mmio_page_fault(addr, gfn, access); | |
ce88decf XG |
3196 | vcpu_cache_mmio_info(vcpu, addr, gfn, access); |
3197 | return 1; | |
3198 | } | |
3199 | ||
3200 | /* | |
3201 | * It's ok if the gva is remapped by other cpus on shadow guest, | |
3202 | * it's a BUG if the gfn is not a mmio page. | |
3203 | */ | |
3204 | if (direct && !check_direct_spte_mmio_pf(spte)) | |
3205 | return -1; | |
3206 | ||
3207 | /* | |
3208 | * If the page table is zapped by other cpus, let CPU fault again on | |
3209 | * the address. | |
3210 | */ | |
3211 | return 0; | |
3212 | } | |
3213 | EXPORT_SYMBOL_GPL(handle_mmio_page_fault_common); | |
3214 | ||
3215 | static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, | |
3216 | u32 error_code, bool direct) | |
3217 | { | |
3218 | int ret; | |
3219 | ||
3220 | ret = handle_mmio_page_fault_common(vcpu, addr, direct); | |
3221 | WARN_ON(ret < 0); | |
3222 | return ret; | |
3223 | } | |
3224 | ||
6aa8b732 | 3225 | static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, |
78b2c54a | 3226 | u32 error_code, bool prefault) |
6aa8b732 | 3227 | { |
e833240f | 3228 | gfn_t gfn; |
e2dec939 | 3229 | int r; |
6aa8b732 | 3230 | |
b8688d51 | 3231 | pgprintk("%s: gva %lx error %x\n", __func__, gva, error_code); |
ce88decf XG |
3232 | |
3233 | if (unlikely(error_code & PFERR_RSVD_MASK)) | |
3234 | return handle_mmio_page_fault(vcpu, gva, error_code, true); | |
3235 | ||
e2dec939 AK |
3236 | r = mmu_topup_memory_caches(vcpu); |
3237 | if (r) | |
3238 | return r; | |
714b93da | 3239 | |
6aa8b732 | 3240 | ASSERT(vcpu); |
ad312c7c | 3241 | ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 | 3242 | |
e833240f | 3243 | gfn = gva >> PAGE_SHIFT; |
6aa8b732 | 3244 | |
e833240f | 3245 | return nonpaging_map(vcpu, gva & PAGE_MASK, |
c7ba5b48 | 3246 | error_code, gfn, prefault); |
6aa8b732 AK |
3247 | } |
3248 | ||
7e1fbeac | 3249 | static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn) |
af585b92 GN |
3250 | { |
3251 | struct kvm_arch_async_pf arch; | |
fb67e14f | 3252 | |
7c90705b | 3253 | arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id; |
af585b92 | 3254 | arch.gfn = gfn; |
c4806acd | 3255 | arch.direct_map = vcpu->arch.mmu.direct_map; |
fb67e14f | 3256 | arch.cr3 = vcpu->arch.mmu.get_cr3(vcpu); |
af585b92 GN |
3257 | |
3258 | return kvm_setup_async_pf(vcpu, gva, gfn, &arch); | |
3259 | } | |
3260 | ||
3261 | static bool can_do_async_pf(struct kvm_vcpu *vcpu) | |
3262 | { | |
3263 | if (unlikely(!irqchip_in_kernel(vcpu->kvm) || | |
3264 | kvm_event_needs_reinjection(vcpu))) | |
3265 | return false; | |
3266 | ||
3267 | return kvm_x86_ops->interrupt_allowed(vcpu); | |
3268 | } | |
3269 | ||
78b2c54a | 3270 | static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, |
612819c3 | 3271 | gva_t gva, pfn_t *pfn, bool write, bool *writable) |
af585b92 GN |
3272 | { |
3273 | bool async; | |
3274 | ||
612819c3 | 3275 | *pfn = gfn_to_pfn_async(vcpu->kvm, gfn, &async, write, writable); |
af585b92 GN |
3276 | |
3277 | if (!async) | |
3278 | return false; /* *pfn has correct page already */ | |
3279 | ||
3280 | put_page(pfn_to_page(*pfn)); | |
3281 | ||
78b2c54a | 3282 | if (!prefault && can_do_async_pf(vcpu)) { |
c9b263d2 | 3283 | trace_kvm_try_async_get_page(gva, gfn); |
af585b92 GN |
3284 | if (kvm_find_async_pf_gfn(vcpu, gfn)) { |
3285 | trace_kvm_async_pf_doublefault(gva, gfn); | |
3286 | kvm_make_request(KVM_REQ_APF_HALT, vcpu); | |
3287 | return true; | |
3288 | } else if (kvm_arch_setup_async_pf(vcpu, gva, gfn)) | |
3289 | return true; | |
3290 | } | |
3291 | ||
612819c3 | 3292 | *pfn = gfn_to_pfn_prot(vcpu->kvm, gfn, write, writable); |
af585b92 GN |
3293 | |
3294 | return false; | |
3295 | } | |
3296 | ||
56028d08 | 3297 | static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, |
78b2c54a | 3298 | bool prefault) |
fb72d167 | 3299 | { |
35149e21 | 3300 | pfn_t pfn; |
fb72d167 | 3301 | int r; |
852e3c19 | 3302 | int level; |
936a5fe6 | 3303 | int force_pt_level; |
05da4558 | 3304 | gfn_t gfn = gpa >> PAGE_SHIFT; |
e930bffe | 3305 | unsigned long mmu_seq; |
612819c3 MT |
3306 | int write = error_code & PFERR_WRITE_MASK; |
3307 | bool map_writable; | |
fb72d167 JR |
3308 | |
3309 | ASSERT(vcpu); | |
3310 | ASSERT(VALID_PAGE(vcpu->arch.mmu.root_hpa)); | |
3311 | ||
ce88decf XG |
3312 | if (unlikely(error_code & PFERR_RSVD_MASK)) |
3313 | return handle_mmio_page_fault(vcpu, gpa, error_code, true); | |
3314 | ||
fb72d167 JR |
3315 | r = mmu_topup_memory_caches(vcpu); |
3316 | if (r) | |
3317 | return r; | |
3318 | ||
936a5fe6 AA |
3319 | force_pt_level = mapping_level_dirty_bitmap(vcpu, gfn); |
3320 | if (likely(!force_pt_level)) { | |
3321 | level = mapping_level(vcpu, gfn); | |
3322 | gfn &= ~(KVM_PAGES_PER_HPAGE(level) - 1); | |
3323 | } else | |
3324 | level = PT_PAGE_TABLE_LEVEL; | |
852e3c19 | 3325 | |
c7ba5b48 XG |
3326 | if (fast_page_fault(vcpu, gpa, level, error_code)) |
3327 | return 0; | |
3328 | ||
e930bffe | 3329 | mmu_seq = vcpu->kvm->mmu_notifier_seq; |
4c2155ce | 3330 | smp_rmb(); |
af585b92 | 3331 | |
78b2c54a | 3332 | if (try_async_pf(vcpu, prefault, gfn, gpa, &pfn, write, &map_writable)) |
af585b92 GN |
3333 | return 0; |
3334 | ||
d7c55201 XG |
3335 | if (handle_abnormal_pfn(vcpu, 0, gfn, pfn, ACC_ALL, &r)) |
3336 | return r; | |
3337 | ||
fb72d167 | 3338 | spin_lock(&vcpu->kvm->mmu_lock); |
e930bffe AA |
3339 | if (mmu_notifier_retry(vcpu, mmu_seq)) |
3340 | goto out_unlock; | |
fb72d167 | 3341 | kvm_mmu_free_some_pages(vcpu); |
936a5fe6 AA |
3342 | if (likely(!force_pt_level)) |
3343 | transparent_hugepage_adjust(vcpu, &gfn, &pfn, &level); | |
612819c3 | 3344 | r = __direct_map(vcpu, gpa, write, map_writable, |
2ec4739d | 3345 | level, gfn, pfn, prefault); |
fb72d167 | 3346 | spin_unlock(&vcpu->kvm->mmu_lock); |
fb72d167 JR |
3347 | |
3348 | return r; | |
e930bffe AA |
3349 | |
3350 | out_unlock: | |
3351 | spin_unlock(&vcpu->kvm->mmu_lock); | |
3352 | kvm_release_pfn_clean(pfn); | |
3353 | return 0; | |
fb72d167 JR |
3354 | } |
3355 | ||
6aa8b732 AK |
3356 | static void nonpaging_free(struct kvm_vcpu *vcpu) |
3357 | { | |
17ac10ad | 3358 | mmu_free_roots(vcpu); |
6aa8b732 AK |
3359 | } |
3360 | ||
52fde8df JR |
3361 | static int nonpaging_init_context(struct kvm_vcpu *vcpu, |
3362 | struct kvm_mmu *context) | |
6aa8b732 | 3363 | { |
6aa8b732 AK |
3364 | context->new_cr3 = nonpaging_new_cr3; |
3365 | context->page_fault = nonpaging_page_fault; | |
6aa8b732 AK |
3366 | context->gva_to_gpa = nonpaging_gva_to_gpa; |
3367 | context->free = nonpaging_free; | |
e8bc217a | 3368 | context->sync_page = nonpaging_sync_page; |
a7052897 | 3369 | context->invlpg = nonpaging_invlpg; |
0f53b5b1 | 3370 | context->update_pte = nonpaging_update_pte; |
cea0f0e7 | 3371 | context->root_level = 0; |
6aa8b732 | 3372 | context->shadow_root_level = PT32E_ROOT_LEVEL; |
17c3ba9d | 3373 | context->root_hpa = INVALID_PAGE; |
c5a78f2b | 3374 | context->direct_map = true; |
2d48a985 | 3375 | context->nx = false; |
6aa8b732 AK |
3376 | return 0; |
3377 | } | |
3378 | ||
d835dfec | 3379 | void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu) |
6aa8b732 | 3380 | { |
1165f5fe | 3381 | ++vcpu->stat.tlb_flush; |
a8eeb04a | 3382 | kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); |
6aa8b732 AK |
3383 | } |
3384 | ||
3385 | static void paging_new_cr3(struct kvm_vcpu *vcpu) | |
3386 | { | |
9f8fe504 | 3387 | pgprintk("%s: cr3 %lx\n", __func__, kvm_read_cr3(vcpu)); |
cea0f0e7 | 3388 | mmu_free_roots(vcpu); |
6aa8b732 AK |
3389 | } |
3390 | ||
5777ed34 JR |
3391 | static unsigned long get_cr3(struct kvm_vcpu *vcpu) |
3392 | { | |
9f8fe504 | 3393 | return kvm_read_cr3(vcpu); |
5777ed34 JR |
3394 | } |
3395 | ||
6389ee94 AK |
3396 | static void inject_page_fault(struct kvm_vcpu *vcpu, |
3397 | struct x86_exception *fault) | |
6aa8b732 | 3398 | { |
6389ee94 | 3399 | vcpu->arch.mmu.inject_page_fault(vcpu, fault); |
6aa8b732 AK |
3400 | } |
3401 | ||
6aa8b732 AK |
3402 | static void paging_free(struct kvm_vcpu *vcpu) |
3403 | { | |
3404 | nonpaging_free(vcpu); | |
3405 | } | |
3406 | ||
3241f22d | 3407 | static bool is_rsvd_bits_set(struct kvm_mmu *mmu, u64 gpte, int level) |
82725b20 DE |
3408 | { |
3409 | int bit7; | |
3410 | ||
3411 | bit7 = (gpte >> 7) & 1; | |
3241f22d | 3412 | return (gpte & mmu->rsvd_bits_mask[bit7][level-1]) != 0; |
82725b20 DE |
3413 | } |
3414 | ||
ce88decf XG |
3415 | static bool sync_mmio_spte(u64 *sptep, gfn_t gfn, unsigned access, |
3416 | int *nr_present) | |
3417 | { | |
3418 | if (unlikely(is_mmio_spte(*sptep))) { | |
3419 | if (gfn != get_mmio_spte_gfn(*sptep)) { | |
3420 | mmu_spte_clear_no_track(sptep); | |
3421 | return true; | |
3422 | } | |
3423 | ||
3424 | (*nr_present)++; | |
3425 | mark_mmio_spte(sptep, gfn, access); | |
3426 | return true; | |
3427 | } | |
3428 | ||
3429 | return false; | |
3430 | } | |
3431 | ||
6aa8b732 AK |
3432 | #define PTTYPE 64 |
3433 | #include "paging_tmpl.h" | |
3434 | #undef PTTYPE | |
3435 | ||
3436 | #define PTTYPE 32 | |
3437 | #include "paging_tmpl.h" | |
3438 | #undef PTTYPE | |
3439 | ||
52fde8df | 3440 | static void reset_rsvds_bits_mask(struct kvm_vcpu *vcpu, |
4d6931c3 | 3441 | struct kvm_mmu *context) |
82725b20 | 3442 | { |
82725b20 DE |
3443 | int maxphyaddr = cpuid_maxphyaddr(vcpu); |
3444 | u64 exb_bit_rsvd = 0; | |
3445 | ||
2d48a985 | 3446 | if (!context->nx) |
82725b20 | 3447 | exb_bit_rsvd = rsvd_bits(63, 63); |
4d6931c3 | 3448 | switch (context->root_level) { |
82725b20 DE |
3449 | case PT32_ROOT_LEVEL: |
3450 | /* no rsvd bits for 2 level 4K page table entries */ | |
3451 | context->rsvd_bits_mask[0][1] = 0; | |
3452 | context->rsvd_bits_mask[0][0] = 0; | |
f815bce8 XG |
3453 | context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; |
3454 | ||
3455 | if (!is_pse(vcpu)) { | |
3456 | context->rsvd_bits_mask[1][1] = 0; | |
3457 | break; | |
3458 | } | |
3459 | ||
82725b20 DE |
3460 | if (is_cpuid_PSE36()) |
3461 | /* 36bits PSE 4MB page */ | |
3462 | context->rsvd_bits_mask[1][1] = rsvd_bits(17, 21); | |
3463 | else | |
3464 | /* 32 bits PSE 4MB page */ | |
3465 | context->rsvd_bits_mask[1][1] = rsvd_bits(13, 21); | |
82725b20 DE |
3466 | break; |
3467 | case PT32E_ROOT_LEVEL: | |
20c466b5 DE |
3468 | context->rsvd_bits_mask[0][2] = |
3469 | rsvd_bits(maxphyaddr, 63) | | |
3470 | rsvd_bits(7, 8) | rsvd_bits(1, 2); /* PDPTE */ | |
82725b20 | 3471 | context->rsvd_bits_mask[0][1] = exb_bit_rsvd | |
4c26b4cd | 3472 | rsvd_bits(maxphyaddr, 62); /* PDE */ |
82725b20 DE |
3473 | context->rsvd_bits_mask[0][0] = exb_bit_rsvd | |
3474 | rsvd_bits(maxphyaddr, 62); /* PTE */ | |
3475 | context->rsvd_bits_mask[1][1] = exb_bit_rsvd | | |
3476 | rsvd_bits(maxphyaddr, 62) | | |
3477 | rsvd_bits(13, 20); /* large page */ | |
f815bce8 | 3478 | context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; |
82725b20 DE |
3479 | break; |
3480 | case PT64_ROOT_LEVEL: | |
3481 | context->rsvd_bits_mask[0][3] = exb_bit_rsvd | | |
3482 | rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8); | |
3483 | context->rsvd_bits_mask[0][2] = exb_bit_rsvd | | |
3484 | rsvd_bits(maxphyaddr, 51) | rsvd_bits(7, 8); | |
3485 | context->rsvd_bits_mask[0][1] = exb_bit_rsvd | | |
4c26b4cd | 3486 | rsvd_bits(maxphyaddr, 51); |
82725b20 DE |
3487 | context->rsvd_bits_mask[0][0] = exb_bit_rsvd | |
3488 | rsvd_bits(maxphyaddr, 51); | |
3489 | context->rsvd_bits_mask[1][3] = context->rsvd_bits_mask[0][3]; | |
e04da980 JR |
3490 | context->rsvd_bits_mask[1][2] = exb_bit_rsvd | |
3491 | rsvd_bits(maxphyaddr, 51) | | |
3492 | rsvd_bits(13, 29); | |
82725b20 | 3493 | context->rsvd_bits_mask[1][1] = exb_bit_rsvd | |
4c26b4cd SY |
3494 | rsvd_bits(maxphyaddr, 51) | |
3495 | rsvd_bits(13, 20); /* large page */ | |
f815bce8 | 3496 | context->rsvd_bits_mask[1][0] = context->rsvd_bits_mask[0][0]; |
82725b20 DE |
3497 | break; |
3498 | } | |
3499 | } | |
3500 | ||
52fde8df JR |
3501 | static int paging64_init_context_common(struct kvm_vcpu *vcpu, |
3502 | struct kvm_mmu *context, | |
3503 | int level) | |
6aa8b732 | 3504 | { |
2d48a985 | 3505 | context->nx = is_nx(vcpu); |
4d6931c3 | 3506 | context->root_level = level; |
2d48a985 | 3507 | |
4d6931c3 | 3508 | reset_rsvds_bits_mask(vcpu, context); |
6aa8b732 AK |
3509 | |
3510 | ASSERT(is_pae(vcpu)); | |
3511 | context->new_cr3 = paging_new_cr3; | |
3512 | context->page_fault = paging64_page_fault; | |
6aa8b732 | 3513 | context->gva_to_gpa = paging64_gva_to_gpa; |
e8bc217a | 3514 | context->sync_page = paging64_sync_page; |
a7052897 | 3515 | context->invlpg = paging64_invlpg; |
0f53b5b1 | 3516 | context->update_pte = paging64_update_pte; |
6aa8b732 | 3517 | context->free = paging_free; |
17ac10ad | 3518 | context->shadow_root_level = level; |
17c3ba9d | 3519 | context->root_hpa = INVALID_PAGE; |
c5a78f2b | 3520 | context->direct_map = false; |
6aa8b732 AK |
3521 | return 0; |
3522 | } | |
3523 | ||
52fde8df JR |
3524 | static int paging64_init_context(struct kvm_vcpu *vcpu, |
3525 | struct kvm_mmu *context) | |
17ac10ad | 3526 | { |
52fde8df | 3527 | return paging64_init_context_common(vcpu, context, PT64_ROOT_LEVEL); |
17ac10ad AK |
3528 | } |
3529 | ||
52fde8df JR |
3530 | static int paging32_init_context(struct kvm_vcpu *vcpu, |
3531 | struct kvm_mmu *context) | |
6aa8b732 | 3532 | { |
2d48a985 | 3533 | context->nx = false; |
4d6931c3 | 3534 | context->root_level = PT32_ROOT_LEVEL; |
2d48a985 | 3535 | |
4d6931c3 | 3536 | reset_rsvds_bits_mask(vcpu, context); |
6aa8b732 AK |
3537 | |
3538 | context->new_cr3 = paging_new_cr3; | |
3539 | context->page_fault = paging32_page_fault; | |
6aa8b732 AK |
3540 | context->gva_to_gpa = paging32_gva_to_gpa; |
3541 | context->free = paging_free; | |
e8bc217a | 3542 | context->sync_page = paging32_sync_page; |
a7052897 | 3543 | context->invlpg = paging32_invlpg; |
0f53b5b1 | 3544 | context->update_pte = paging32_update_pte; |
6aa8b732 | 3545 | context->shadow_root_level = PT32E_ROOT_LEVEL; |
17c3ba9d | 3546 | context->root_hpa = INVALID_PAGE; |
c5a78f2b | 3547 | context->direct_map = false; |
6aa8b732 AK |
3548 | return 0; |
3549 | } | |
3550 | ||
52fde8df JR |
3551 | static int paging32E_init_context(struct kvm_vcpu *vcpu, |
3552 | struct kvm_mmu *context) | |
6aa8b732 | 3553 | { |
52fde8df | 3554 | return paging64_init_context_common(vcpu, context, PT32E_ROOT_LEVEL); |
6aa8b732 AK |
3555 | } |
3556 | ||
fb72d167 JR |
3557 | static int init_kvm_tdp_mmu(struct kvm_vcpu *vcpu) |
3558 | { | |
14dfe855 | 3559 | struct kvm_mmu *context = vcpu->arch.walk_mmu; |
fb72d167 | 3560 | |
c445f8ef | 3561 | context->base_role.word = 0; |
fb72d167 JR |
3562 | context->new_cr3 = nonpaging_new_cr3; |
3563 | context->page_fault = tdp_page_fault; | |
3564 | context->free = nonpaging_free; | |
e8bc217a | 3565 | context->sync_page = nonpaging_sync_page; |
a7052897 | 3566 | context->invlpg = nonpaging_invlpg; |
0f53b5b1 | 3567 | context->update_pte = nonpaging_update_pte; |
67253af5 | 3568 | context->shadow_root_level = kvm_x86_ops->get_tdp_level(); |
fb72d167 | 3569 | context->root_hpa = INVALID_PAGE; |
c5a78f2b | 3570 | context->direct_map = true; |
1c97f0a0 | 3571 | context->set_cr3 = kvm_x86_ops->set_tdp_cr3; |
5777ed34 | 3572 | context->get_cr3 = get_cr3; |
e4e517b4 | 3573 | context->get_pdptr = kvm_pdptr_read; |
cb659db8 | 3574 | context->inject_page_fault = kvm_inject_page_fault; |
fb72d167 JR |
3575 | |
3576 | if (!is_paging(vcpu)) { | |
2d48a985 | 3577 | context->nx = false; |
fb72d167 JR |
3578 | context->gva_to_gpa = nonpaging_gva_to_gpa; |
3579 | context->root_level = 0; | |
3580 | } else if (is_long_mode(vcpu)) { | |
2d48a985 | 3581 | context->nx = is_nx(vcpu); |
fb72d167 | 3582 | context->root_level = PT64_ROOT_LEVEL; |
4d6931c3 DB |
3583 | reset_rsvds_bits_mask(vcpu, context); |
3584 | context->gva_to_gpa = paging64_gva_to_gpa; | |
fb72d167 | 3585 | } else if (is_pae(vcpu)) { |
2d48a985 | 3586 | context->nx = is_nx(vcpu); |
fb72d167 | 3587 | context->root_level = PT32E_ROOT_LEVEL; |
4d6931c3 DB |
3588 | reset_rsvds_bits_mask(vcpu, context); |
3589 | context->gva_to_gpa = paging64_gva_to_gpa; | |
fb72d167 | 3590 | } else { |
2d48a985 | 3591 | context->nx = false; |
fb72d167 | 3592 | context->root_level = PT32_ROOT_LEVEL; |
4d6931c3 DB |
3593 | reset_rsvds_bits_mask(vcpu, context); |
3594 | context->gva_to_gpa = paging32_gva_to_gpa; | |
fb72d167 JR |
3595 | } |
3596 | ||
3597 | return 0; | |
3598 | } | |
3599 | ||
52fde8df | 3600 | int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context) |
6aa8b732 | 3601 | { |
a770f6f2 | 3602 | int r; |
411c588d | 3603 | bool smep = kvm_read_cr4_bits(vcpu, X86_CR4_SMEP); |
6aa8b732 | 3604 | ASSERT(vcpu); |
ad312c7c | 3605 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
6aa8b732 AK |
3606 | |
3607 | if (!is_paging(vcpu)) | |
52fde8df | 3608 | r = nonpaging_init_context(vcpu, context); |
a9058ecd | 3609 | else if (is_long_mode(vcpu)) |
52fde8df | 3610 | r = paging64_init_context(vcpu, context); |
6aa8b732 | 3611 | else if (is_pae(vcpu)) |
52fde8df | 3612 | r = paging32E_init_context(vcpu, context); |
6aa8b732 | 3613 | else |
52fde8df | 3614 | r = paging32_init_context(vcpu, context); |
a770f6f2 | 3615 | |
5b7e0102 | 3616 | vcpu->arch.mmu.base_role.cr4_pae = !!is_pae(vcpu); |
f43addd4 | 3617 | vcpu->arch.mmu.base_role.cr0_wp = is_write_protection(vcpu); |
411c588d AK |
3618 | vcpu->arch.mmu.base_role.smep_andnot_wp |
3619 | = smep && !is_write_protection(vcpu); | |
52fde8df JR |
3620 | |
3621 | return r; | |
3622 | } | |
3623 | EXPORT_SYMBOL_GPL(kvm_init_shadow_mmu); | |
3624 | ||
3625 | static int init_kvm_softmmu(struct kvm_vcpu *vcpu) | |
3626 | { | |
14dfe855 | 3627 | int r = kvm_init_shadow_mmu(vcpu, vcpu->arch.walk_mmu); |
52fde8df | 3628 | |
14dfe855 JR |
3629 | vcpu->arch.walk_mmu->set_cr3 = kvm_x86_ops->set_cr3; |
3630 | vcpu->arch.walk_mmu->get_cr3 = get_cr3; | |
e4e517b4 | 3631 | vcpu->arch.walk_mmu->get_pdptr = kvm_pdptr_read; |
14dfe855 | 3632 | vcpu->arch.walk_mmu->inject_page_fault = kvm_inject_page_fault; |
a770f6f2 AK |
3633 | |
3634 | return r; | |
6aa8b732 AK |
3635 | } |
3636 | ||
02f59dc9 JR |
3637 | static int init_kvm_nested_mmu(struct kvm_vcpu *vcpu) |
3638 | { | |
3639 | struct kvm_mmu *g_context = &vcpu->arch.nested_mmu; | |
3640 | ||
3641 | g_context->get_cr3 = get_cr3; | |
e4e517b4 | 3642 | g_context->get_pdptr = kvm_pdptr_read; |
02f59dc9 JR |
3643 | g_context->inject_page_fault = kvm_inject_page_fault; |
3644 | ||
3645 | /* | |
3646 | * Note that arch.mmu.gva_to_gpa translates l2_gva to l1_gpa. The | |
3647 | * translation of l2_gpa to l1_gpa addresses is done using the | |
3648 | * arch.nested_mmu.gva_to_gpa function. Basically the gva_to_gpa | |
3649 | * functions between mmu and nested_mmu are swapped. | |
3650 | */ | |
3651 | if (!is_paging(vcpu)) { | |
2d48a985 | 3652 | g_context->nx = false; |
02f59dc9 JR |
3653 | g_context->root_level = 0; |
3654 | g_context->gva_to_gpa = nonpaging_gva_to_gpa_nested; | |
3655 | } else if (is_long_mode(vcpu)) { | |
2d48a985 | 3656 | g_context->nx = is_nx(vcpu); |
02f59dc9 | 3657 | g_context->root_level = PT64_ROOT_LEVEL; |
4d6931c3 | 3658 | reset_rsvds_bits_mask(vcpu, g_context); |
02f59dc9 JR |
3659 | g_context->gva_to_gpa = paging64_gva_to_gpa_nested; |
3660 | } else if (is_pae(vcpu)) { | |
2d48a985 | 3661 | g_context->nx = is_nx(vcpu); |
02f59dc9 | 3662 | g_context->root_level = PT32E_ROOT_LEVEL; |
4d6931c3 | 3663 | reset_rsvds_bits_mask(vcpu, g_context); |
02f59dc9 JR |
3664 | g_context->gva_to_gpa = paging64_gva_to_gpa_nested; |
3665 | } else { | |
2d48a985 | 3666 | g_context->nx = false; |
02f59dc9 | 3667 | g_context->root_level = PT32_ROOT_LEVEL; |
4d6931c3 | 3668 | reset_rsvds_bits_mask(vcpu, g_context); |
02f59dc9 JR |
3669 | g_context->gva_to_gpa = paging32_gva_to_gpa_nested; |
3670 | } | |
3671 | ||
3672 | return 0; | |
3673 | } | |
3674 | ||
fb72d167 JR |
3675 | static int init_kvm_mmu(struct kvm_vcpu *vcpu) |
3676 | { | |
02f59dc9 JR |
3677 | if (mmu_is_nested(vcpu)) |
3678 | return init_kvm_nested_mmu(vcpu); | |
3679 | else if (tdp_enabled) | |
fb72d167 JR |
3680 | return init_kvm_tdp_mmu(vcpu); |
3681 | else | |
3682 | return init_kvm_softmmu(vcpu); | |
3683 | } | |
3684 | ||
6aa8b732 AK |
3685 | static void destroy_kvm_mmu(struct kvm_vcpu *vcpu) |
3686 | { | |
3687 | ASSERT(vcpu); | |
62ad0755 SY |
3688 | if (VALID_PAGE(vcpu->arch.mmu.root_hpa)) |
3689 | /* mmu.free() should set root_hpa = INVALID_PAGE */ | |
ad312c7c | 3690 | vcpu->arch.mmu.free(vcpu); |
6aa8b732 AK |
3691 | } |
3692 | ||
3693 | int kvm_mmu_reset_context(struct kvm_vcpu *vcpu) | |
17c3ba9d AK |
3694 | { |
3695 | destroy_kvm_mmu(vcpu); | |
f8f7e5ee | 3696 | return init_kvm_mmu(vcpu); |
17c3ba9d | 3697 | } |
8668a3c4 | 3698 | EXPORT_SYMBOL_GPL(kvm_mmu_reset_context); |
17c3ba9d AK |
3699 | |
3700 | int kvm_mmu_load(struct kvm_vcpu *vcpu) | |
6aa8b732 | 3701 | { |
714b93da AK |
3702 | int r; |
3703 | ||
e2dec939 | 3704 | r = mmu_topup_memory_caches(vcpu); |
17c3ba9d AK |
3705 | if (r) |
3706 | goto out; | |
8986ecc0 | 3707 | r = mmu_alloc_roots(vcpu); |
8facbbff | 3708 | spin_lock(&vcpu->kvm->mmu_lock); |
0ba73cda | 3709 | mmu_sync_roots(vcpu); |
aaee2c94 | 3710 | spin_unlock(&vcpu->kvm->mmu_lock); |
8986ecc0 MT |
3711 | if (r) |
3712 | goto out; | |
3662cb1c | 3713 | /* set_cr3() should ensure TLB has been flushed */ |
f43addd4 | 3714 | vcpu->arch.mmu.set_cr3(vcpu, vcpu->arch.mmu.root_hpa); |
714b93da AK |
3715 | out: |
3716 | return r; | |
6aa8b732 | 3717 | } |
17c3ba9d AK |
3718 | EXPORT_SYMBOL_GPL(kvm_mmu_load); |
3719 | ||
3720 | void kvm_mmu_unload(struct kvm_vcpu *vcpu) | |
3721 | { | |
3722 | mmu_free_roots(vcpu); | |
3723 | } | |
4b16184c | 3724 | EXPORT_SYMBOL_GPL(kvm_mmu_unload); |
6aa8b732 | 3725 | |
0028425f | 3726 | static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, |
7c562522 XG |
3727 | struct kvm_mmu_page *sp, u64 *spte, |
3728 | const void *new) | |
0028425f | 3729 | { |
30945387 | 3730 | if (sp->role.level != PT_PAGE_TABLE_LEVEL) { |
7e4e4056 JR |
3731 | ++vcpu->kvm->stat.mmu_pde_zapped; |
3732 | return; | |
30945387 | 3733 | } |
0028425f | 3734 | |
4cee5764 | 3735 | ++vcpu->kvm->stat.mmu_pte_updated; |
7c562522 | 3736 | vcpu->arch.mmu.update_pte(vcpu, sp, spte, new); |
0028425f AK |
3737 | } |
3738 | ||
79539cec AK |
3739 | static bool need_remote_flush(u64 old, u64 new) |
3740 | { | |
3741 | if (!is_shadow_present_pte(old)) | |
3742 | return false; | |
3743 | if (!is_shadow_present_pte(new)) | |
3744 | return true; | |
3745 | if ((old ^ new) & PT64_BASE_ADDR_MASK) | |
3746 | return true; | |
3747 | old ^= PT64_NX_MASK; | |
3748 | new ^= PT64_NX_MASK; | |
3749 | return (old & ~new & PT64_PERM_MASK) != 0; | |
3750 | } | |
3751 | ||
0671a8e7 XG |
3752 | static void mmu_pte_write_flush_tlb(struct kvm_vcpu *vcpu, bool zap_page, |
3753 | bool remote_flush, bool local_flush) | |
79539cec | 3754 | { |
0671a8e7 XG |
3755 | if (zap_page) |
3756 | return; | |
3757 | ||
3758 | if (remote_flush) | |
79539cec | 3759 | kvm_flush_remote_tlbs(vcpu->kvm); |
0671a8e7 | 3760 | else if (local_flush) |
79539cec AK |
3761 | kvm_mmu_flush_tlb(vcpu); |
3762 | } | |
3763 | ||
889e5cbc XG |
3764 | static u64 mmu_pte_write_fetch_gpte(struct kvm_vcpu *vcpu, gpa_t *gpa, |
3765 | const u8 *new, int *bytes) | |
da4a00f0 | 3766 | { |
889e5cbc XG |
3767 | u64 gentry; |
3768 | int r; | |
72016f3a | 3769 | |
72016f3a AK |
3770 | /* |
3771 | * Assume that the pte write on a page table of the same type | |
49b26e26 XG |
3772 | * as the current vcpu paging mode since we update the sptes only |
3773 | * when they have the same mode. | |
72016f3a | 3774 | */ |
889e5cbc | 3775 | if (is_pae(vcpu) && *bytes == 4) { |
72016f3a | 3776 | /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ |
889e5cbc XG |
3777 | *gpa &= ~(gpa_t)7; |
3778 | *bytes = 8; | |
3779 | r = kvm_read_guest(vcpu->kvm, *gpa, &gentry, min(*bytes, 8)); | |
72016f3a AK |
3780 | if (r) |
3781 | gentry = 0; | |
08e850c6 AK |
3782 | new = (const u8 *)&gentry; |
3783 | } | |
3784 | ||
889e5cbc | 3785 | switch (*bytes) { |
08e850c6 AK |
3786 | case 4: |
3787 | gentry = *(const u32 *)new; | |
3788 | break; | |
3789 | case 8: | |
3790 | gentry = *(const u64 *)new; | |
3791 | break; | |
3792 | default: | |
3793 | gentry = 0; | |
3794 | break; | |
72016f3a AK |
3795 | } |
3796 | ||
889e5cbc XG |
3797 | return gentry; |
3798 | } | |
3799 | ||
3800 | /* | |
3801 | * If we're seeing too many writes to a page, it may no longer be a page table, | |
3802 | * or we may be forking, in which case it is better to unmap the page. | |
3803 | */ | |
a138fe75 | 3804 | static bool detect_write_flooding(struct kvm_mmu_page *sp) |
889e5cbc | 3805 | { |
a30f47cb XG |
3806 | /* |
3807 | * Skip write-flooding detected for the sp whose level is 1, because | |
3808 | * it can become unsync, then the guest page is not write-protected. | |
3809 | */ | |
f71fa31f | 3810 | if (sp->role.level == PT_PAGE_TABLE_LEVEL) |
a30f47cb | 3811 | return false; |
3246af0e | 3812 | |
a30f47cb | 3813 | return ++sp->write_flooding_count >= 3; |
889e5cbc XG |
3814 | } |
3815 | ||
3816 | /* | |
3817 | * Misaligned accesses are too much trouble to fix up; also, they usually | |
3818 | * indicate a page is not used as a page table. | |
3819 | */ | |
3820 | static bool detect_write_misaligned(struct kvm_mmu_page *sp, gpa_t gpa, | |
3821 | int bytes) | |
3822 | { | |
3823 | unsigned offset, pte_size, misaligned; | |
3824 | ||
3825 | pgprintk("misaligned: gpa %llx bytes %d role %x\n", | |
3826 | gpa, bytes, sp->role.word); | |
3827 | ||
3828 | offset = offset_in_page(gpa); | |
3829 | pte_size = sp->role.cr4_pae ? 8 : 4; | |
5d9ca30e XG |
3830 | |
3831 | /* | |
3832 | * Sometimes, the OS only writes the last one bytes to update status | |
3833 | * bits, for example, in linux, andb instruction is used in clear_bit(). | |
3834 | */ | |
3835 | if (!(offset & (pte_size - 1)) && bytes == 1) | |
3836 | return false; | |
3837 | ||
889e5cbc XG |
3838 | misaligned = (offset ^ (offset + bytes - 1)) & ~(pte_size - 1); |
3839 | misaligned |= bytes < 4; | |
3840 | ||
3841 | return misaligned; | |
3842 | } | |
3843 | ||
3844 | static u64 *get_written_sptes(struct kvm_mmu_page *sp, gpa_t gpa, int *nspte) | |
3845 | { | |
3846 | unsigned page_offset, quadrant; | |
3847 | u64 *spte; | |
3848 | int level; | |
3849 | ||
3850 | page_offset = offset_in_page(gpa); | |
3851 | level = sp->role.level; | |
3852 | *nspte = 1; | |
3853 | if (!sp->role.cr4_pae) { | |
3854 | page_offset <<= 1; /* 32->64 */ | |
3855 | /* | |
3856 | * A 32-bit pde maps 4MB while the shadow pdes map | |
3857 | * only 2MB. So we need to double the offset again | |
3858 | * and zap two pdes instead of one. | |
3859 | */ | |
3860 | if (level == PT32_ROOT_LEVEL) { | |
3861 | page_offset &= ~7; /* kill rounding error */ | |
3862 | page_offset <<= 1; | |
3863 | *nspte = 2; | |
3864 | } | |
3865 | quadrant = page_offset >> PAGE_SHIFT; | |
3866 | page_offset &= ~PAGE_MASK; | |
3867 | if (quadrant != sp->role.quadrant) | |
3868 | return NULL; | |
3869 | } | |
3870 | ||
3871 | spte = &sp->spt[page_offset / sizeof(*spte)]; | |
3872 | return spte; | |
3873 | } | |
3874 | ||
3875 | void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, | |
3876 | const u8 *new, int bytes) | |
3877 | { | |
3878 | gfn_t gfn = gpa >> PAGE_SHIFT; | |
3879 | union kvm_mmu_page_role mask = { .word = 0 }; | |
3880 | struct kvm_mmu_page *sp; | |
3881 | struct hlist_node *node; | |
3882 | LIST_HEAD(invalid_list); | |
3883 | u64 entry, gentry, *spte; | |
3884 | int npte; | |
a30f47cb | 3885 | bool remote_flush, local_flush, zap_page; |
889e5cbc XG |
3886 | |
3887 | /* | |
3888 | * If we don't have indirect shadow pages, it means no page is | |
3889 | * write-protected, so we can exit simply. | |
3890 | */ | |
3891 | if (!ACCESS_ONCE(vcpu->kvm->arch.indirect_shadow_pages)) | |
3892 | return; | |
3893 | ||
3894 | zap_page = remote_flush = local_flush = false; | |
3895 | ||
3896 | pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); | |
3897 | ||
3898 | gentry = mmu_pte_write_fetch_gpte(vcpu, &gpa, new, &bytes); | |
3899 | ||
3900 | /* | |
3901 | * No need to care whether allocation memory is successful | |
3902 | * or not since pte prefetch is skiped if it does not have | |
3903 | * enough objects in the cache. | |
3904 | */ | |
3905 | mmu_topup_memory_caches(vcpu); | |
3906 | ||
3907 | spin_lock(&vcpu->kvm->mmu_lock); | |
3908 | ++vcpu->kvm->stat.mmu_pte_write; | |
0375f7fa | 3909 | kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); |
889e5cbc | 3910 | |
fa1de2bf | 3911 | mask.cr0_wp = mask.cr4_pae = mask.nxe = 1; |
f41d335a | 3912 | for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn, node) { |
a30f47cb | 3913 | if (detect_write_misaligned(sp, gpa, bytes) || |
a138fe75 | 3914 | detect_write_flooding(sp)) { |
0671a8e7 | 3915 | zap_page |= !!kvm_mmu_prepare_zap_page(vcpu->kvm, sp, |
f41d335a | 3916 | &invalid_list); |
4cee5764 | 3917 | ++vcpu->kvm->stat.mmu_flooded; |
0e7bc4b9 AK |
3918 | continue; |
3919 | } | |
889e5cbc XG |
3920 | |
3921 | spte = get_written_sptes(sp, gpa, &npte); | |
3922 | if (!spte) | |
3923 | continue; | |
3924 | ||
0671a8e7 | 3925 | local_flush = true; |
ac1b714e | 3926 | while (npte--) { |
79539cec | 3927 | entry = *spte; |
38e3b2b2 | 3928 | mmu_page_zap_pte(vcpu->kvm, sp, spte); |
fa1de2bf XG |
3929 | if (gentry && |
3930 | !((sp->role.word ^ vcpu->arch.mmu.base_role.word) | |
f759e2b4 | 3931 | & mask.word) && rmap_can_add(vcpu)) |
7c562522 | 3932 | mmu_pte_write_new_pte(vcpu, sp, spte, &gentry); |
0671a8e7 XG |
3933 | if (!remote_flush && need_remote_flush(entry, *spte)) |
3934 | remote_flush = true; | |
ac1b714e | 3935 | ++spte; |
9b7a0325 | 3936 | } |
9b7a0325 | 3937 | } |
0671a8e7 | 3938 | mmu_pte_write_flush_tlb(vcpu, zap_page, remote_flush, local_flush); |
d98ba053 | 3939 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
0375f7fa | 3940 | kvm_mmu_audit(vcpu, AUDIT_POST_PTE_WRITE); |
aaee2c94 | 3941 | spin_unlock(&vcpu->kvm->mmu_lock); |
da4a00f0 AK |
3942 | } |
3943 | ||
a436036b AK |
3944 | int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva) |
3945 | { | |
10589a46 MT |
3946 | gpa_t gpa; |
3947 | int r; | |
a436036b | 3948 | |
c5a78f2b | 3949 | if (vcpu->arch.mmu.direct_map) |
60f24784 AK |
3950 | return 0; |
3951 | ||
1871c602 | 3952 | gpa = kvm_mmu_gva_to_gpa_read(vcpu, gva, NULL); |
10589a46 | 3953 | |
10589a46 | 3954 | r = kvm_mmu_unprotect_page(vcpu->kvm, gpa >> PAGE_SHIFT); |
1cb3f3ae | 3955 | |
10589a46 | 3956 | return r; |
a436036b | 3957 | } |
577bdc49 | 3958 | EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page_virt); |
a436036b | 3959 | |
22d95b12 | 3960 | void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu) |
ebeace86 | 3961 | { |
d98ba053 | 3962 | LIST_HEAD(invalid_list); |
103ad25a | 3963 | |
e0df7b9f | 3964 | while (kvm_mmu_available_pages(vcpu->kvm) < KVM_REFILL_PAGES && |
3b80fffe | 3965 | !list_empty(&vcpu->kvm->arch.active_mmu_pages)) { |
4db35314 | 3966 | struct kvm_mmu_page *sp; |
ebeace86 | 3967 | |
f05e70ac | 3968 | sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev, |
4db35314 | 3969 | struct kvm_mmu_page, link); |
e0df7b9f | 3970 | kvm_mmu_prepare_zap_page(vcpu->kvm, sp, &invalid_list); |
4cee5764 | 3971 | ++vcpu->kvm->stat.mmu_recycled; |
ebeace86 | 3972 | } |
aa6bd187 | 3973 | kvm_mmu_commit_zap_page(vcpu->kvm, &invalid_list); |
ebeace86 | 3974 | } |
ebeace86 | 3975 | |
1cb3f3ae XG |
3976 | static bool is_mmio_page_fault(struct kvm_vcpu *vcpu, gva_t addr) |
3977 | { | |
3978 | if (vcpu->arch.mmu.direct_map || mmu_is_nested(vcpu)) | |
3979 | return vcpu_match_mmio_gpa(vcpu, addr); | |
3980 | ||
3981 | return vcpu_match_mmio_gva(vcpu, addr); | |
3982 | } | |
3983 | ||
dc25e89e AP |
3984 | int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t cr2, u32 error_code, |
3985 | void *insn, int insn_len) | |
3067714c | 3986 | { |
1cb3f3ae | 3987 | int r, emulation_type = EMULTYPE_RETRY; |
3067714c AK |
3988 | enum emulation_result er; |
3989 | ||
56028d08 | 3990 | r = vcpu->arch.mmu.page_fault(vcpu, cr2, error_code, false); |
3067714c AK |
3991 | if (r < 0) |
3992 | goto out; | |
3993 | ||
3994 | if (!r) { | |
3995 | r = 1; | |
3996 | goto out; | |
3997 | } | |
3998 | ||
1cb3f3ae XG |
3999 | if (is_mmio_page_fault(vcpu, cr2)) |
4000 | emulation_type = 0; | |
4001 | ||
4002 | er = x86_emulate_instruction(vcpu, cr2, emulation_type, insn, insn_len); | |
3067714c AK |
4003 | |
4004 | switch (er) { | |
4005 | case EMULATE_DONE: | |
4006 | return 1; | |
4007 | case EMULATE_DO_MMIO: | |
4008 | ++vcpu->stat.mmio_exits; | |
6d77dbfc | 4009 | /* fall through */ |
3067714c | 4010 | case EMULATE_FAIL: |
3f5d18a9 | 4011 | return 0; |
3067714c AK |
4012 | default: |
4013 | BUG(); | |
4014 | } | |
4015 | out: | |
3067714c AK |
4016 | return r; |
4017 | } | |
4018 | EXPORT_SYMBOL_GPL(kvm_mmu_page_fault); | |
4019 | ||
a7052897 MT |
4020 | void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva) |
4021 | { | |
a7052897 | 4022 | vcpu->arch.mmu.invlpg(vcpu, gva); |
a7052897 MT |
4023 | kvm_mmu_flush_tlb(vcpu); |
4024 | ++vcpu->stat.invlpg; | |
4025 | } | |
4026 | EXPORT_SYMBOL_GPL(kvm_mmu_invlpg); | |
4027 | ||
18552672 JR |
4028 | void kvm_enable_tdp(void) |
4029 | { | |
4030 | tdp_enabled = true; | |
4031 | } | |
4032 | EXPORT_SYMBOL_GPL(kvm_enable_tdp); | |
4033 | ||
5f4cb662 JR |
4034 | void kvm_disable_tdp(void) |
4035 | { | |
4036 | tdp_enabled = false; | |
4037 | } | |
4038 | EXPORT_SYMBOL_GPL(kvm_disable_tdp); | |
4039 | ||
6aa8b732 AK |
4040 | static void free_mmu_pages(struct kvm_vcpu *vcpu) |
4041 | { | |
ad312c7c | 4042 | free_page((unsigned long)vcpu->arch.mmu.pae_root); |
81407ca5 JR |
4043 | if (vcpu->arch.mmu.lm_root != NULL) |
4044 | free_page((unsigned long)vcpu->arch.mmu.lm_root); | |
6aa8b732 AK |
4045 | } |
4046 | ||
4047 | static int alloc_mmu_pages(struct kvm_vcpu *vcpu) | |
4048 | { | |
17ac10ad | 4049 | struct page *page; |
6aa8b732 AK |
4050 | int i; |
4051 | ||
4052 | ASSERT(vcpu); | |
4053 | ||
17ac10ad AK |
4054 | /* |
4055 | * When emulating 32-bit mode, cr3 is only 32 bits even on x86_64. | |
4056 | * Therefore we need to allocate shadow page tables in the first | |
4057 | * 4GB of memory, which happens to fit the DMA32 zone. | |
4058 | */ | |
4059 | page = alloc_page(GFP_KERNEL | __GFP_DMA32); | |
4060 | if (!page) | |
d7fa6ab2 WY |
4061 | return -ENOMEM; |
4062 | ||
ad312c7c | 4063 | vcpu->arch.mmu.pae_root = page_address(page); |
17ac10ad | 4064 | for (i = 0; i < 4; ++i) |
ad312c7c | 4065 | vcpu->arch.mmu.pae_root[i] = INVALID_PAGE; |
17ac10ad | 4066 | |
6aa8b732 | 4067 | return 0; |
6aa8b732 AK |
4068 | } |
4069 | ||
8018c27b | 4070 | int kvm_mmu_create(struct kvm_vcpu *vcpu) |
6aa8b732 | 4071 | { |
6aa8b732 | 4072 | ASSERT(vcpu); |
e459e322 XG |
4073 | |
4074 | vcpu->arch.walk_mmu = &vcpu->arch.mmu; | |
4075 | vcpu->arch.mmu.root_hpa = INVALID_PAGE; | |
4076 | vcpu->arch.mmu.translate_gpa = translate_gpa; | |
4077 | vcpu->arch.nested_mmu.translate_gpa = translate_nested_gpa; | |
6aa8b732 | 4078 | |
8018c27b IM |
4079 | return alloc_mmu_pages(vcpu); |
4080 | } | |
6aa8b732 | 4081 | |
8018c27b IM |
4082 | int kvm_mmu_setup(struct kvm_vcpu *vcpu) |
4083 | { | |
4084 | ASSERT(vcpu); | |
ad312c7c | 4085 | ASSERT(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); |
2c264957 | 4086 | |
8018c27b | 4087 | return init_kvm_mmu(vcpu); |
6aa8b732 AK |
4088 | } |
4089 | ||
90cb0529 | 4090 | void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot) |
6aa8b732 | 4091 | { |
4db35314 | 4092 | struct kvm_mmu_page *sp; |
d13bc5b5 | 4093 | bool flush = false; |
6aa8b732 | 4094 | |
f05e70ac | 4095 | list_for_each_entry(sp, &kvm->arch.active_mmu_pages, link) { |
6aa8b732 AK |
4096 | int i; |
4097 | u64 *pt; | |
4098 | ||
291f26bc | 4099 | if (!test_bit(slot, sp->slot_bitmap)) |
6aa8b732 AK |
4100 | continue; |
4101 | ||
4db35314 | 4102 | pt = sp->spt; |
8234b22e | 4103 | for (i = 0; i < PT64_ENT_PER_PAGE; ++i) { |
da8dc75f XG |
4104 | if (!is_shadow_present_pte(pt[i]) || |
4105 | !is_last_spte(pt[i], sp->role.level)) | |
4106 | continue; | |
4107 | ||
49fde340 | 4108 | spte_write_protect(kvm, &pt[i], &flush, false); |
8234b22e | 4109 | } |
6aa8b732 | 4110 | } |
171d595d | 4111 | kvm_flush_remote_tlbs(kvm); |
6aa8b732 | 4112 | } |
37a7d8b0 | 4113 | |
90cb0529 | 4114 | void kvm_mmu_zap_all(struct kvm *kvm) |
e0fa826f | 4115 | { |
4db35314 | 4116 | struct kvm_mmu_page *sp, *node; |
d98ba053 | 4117 | LIST_HEAD(invalid_list); |
e0fa826f | 4118 | |
aaee2c94 | 4119 | spin_lock(&kvm->mmu_lock); |
3246af0e | 4120 | restart: |
f05e70ac | 4121 | list_for_each_entry_safe(sp, node, &kvm->arch.active_mmu_pages, link) |
d98ba053 | 4122 | if (kvm_mmu_prepare_zap_page(kvm, sp, &invalid_list)) |
3246af0e XG |
4123 | goto restart; |
4124 | ||
d98ba053 | 4125 | kvm_mmu_commit_zap_page(kvm, &invalid_list); |
aaee2c94 | 4126 | spin_unlock(&kvm->mmu_lock); |
e0fa826f DL |
4127 | } |
4128 | ||
3d56cbdf JK |
4129 | static void kvm_mmu_remove_some_alloc_mmu_pages(struct kvm *kvm, |
4130 | struct list_head *invalid_list) | |
3ee16c81 IE |
4131 | { |
4132 | struct kvm_mmu_page *page; | |
4133 | ||
4134 | page = container_of(kvm->arch.active_mmu_pages.prev, | |
4135 | struct kvm_mmu_page, link); | |
3d56cbdf | 4136 | kvm_mmu_prepare_zap_page(kvm, page, invalid_list); |
3ee16c81 IE |
4137 | } |
4138 | ||
1495f230 | 4139 | static int mmu_shrink(struct shrinker *shrink, struct shrink_control *sc) |
3ee16c81 IE |
4140 | { |
4141 | struct kvm *kvm; | |
1495f230 | 4142 | int nr_to_scan = sc->nr_to_scan; |
45221ab6 DH |
4143 | |
4144 | if (nr_to_scan == 0) | |
4145 | goto out; | |
3ee16c81 | 4146 | |
e935b837 | 4147 | raw_spin_lock(&kvm_lock); |
3ee16c81 IE |
4148 | |
4149 | list_for_each_entry(kvm, &vm_list, vm_list) { | |
3d56cbdf | 4150 | int idx; |
d98ba053 | 4151 | LIST_HEAD(invalid_list); |
3ee16c81 | 4152 | |
19526396 GN |
4153 | /* |
4154 | * n_used_mmu_pages is accessed without holding kvm->mmu_lock | |
4155 | * here. We may skip a VM instance errorneosly, but we do not | |
4156 | * want to shrink a VM that only started to populate its MMU | |
4157 | * anyway. | |
4158 | */ | |
4159 | if (kvm->arch.n_used_mmu_pages > 0) { | |
4160 | if (!nr_to_scan--) | |
4161 | break; | |
4162 | continue; | |
4163 | } | |
4164 | ||
f656ce01 | 4165 | idx = srcu_read_lock(&kvm->srcu); |
3ee16c81 | 4166 | spin_lock(&kvm->mmu_lock); |
3ee16c81 | 4167 | |
19526396 | 4168 | kvm_mmu_remove_some_alloc_mmu_pages(kvm, &invalid_list); |
d98ba053 | 4169 | kvm_mmu_commit_zap_page(kvm, &invalid_list); |
19526396 | 4170 | |
3ee16c81 | 4171 | spin_unlock(&kvm->mmu_lock); |
f656ce01 | 4172 | srcu_read_unlock(&kvm->srcu, idx); |
19526396 GN |
4173 | |
4174 | list_move_tail(&kvm->vm_list, &vm_list); | |
4175 | break; | |
3ee16c81 | 4176 | } |
3ee16c81 | 4177 | |
e935b837 | 4178 | raw_spin_unlock(&kvm_lock); |
3ee16c81 | 4179 | |
45221ab6 DH |
4180 | out: |
4181 | return percpu_counter_read_positive(&kvm_total_used_mmu_pages); | |
3ee16c81 IE |
4182 | } |
4183 | ||
4184 | static struct shrinker mmu_shrinker = { | |
4185 | .shrink = mmu_shrink, | |
4186 | .seeks = DEFAULT_SEEKS * 10, | |
4187 | }; | |
4188 | ||
2ddfd20e | 4189 | static void mmu_destroy_caches(void) |
b5a33a75 | 4190 | { |
53c07b18 XG |
4191 | if (pte_list_desc_cache) |
4192 | kmem_cache_destroy(pte_list_desc_cache); | |
d3d25b04 AK |
4193 | if (mmu_page_header_cache) |
4194 | kmem_cache_destroy(mmu_page_header_cache); | |
b5a33a75 AK |
4195 | } |
4196 | ||
4197 | int kvm_mmu_module_init(void) | |
4198 | { | |
53c07b18 XG |
4199 | pte_list_desc_cache = kmem_cache_create("pte_list_desc", |
4200 | sizeof(struct pte_list_desc), | |
20c2df83 | 4201 | 0, 0, NULL); |
53c07b18 | 4202 | if (!pte_list_desc_cache) |
b5a33a75 AK |
4203 | goto nomem; |
4204 | ||
d3d25b04 AK |
4205 | mmu_page_header_cache = kmem_cache_create("kvm_mmu_page_header", |
4206 | sizeof(struct kvm_mmu_page), | |
20c2df83 | 4207 | 0, 0, NULL); |
d3d25b04 AK |
4208 | if (!mmu_page_header_cache) |
4209 | goto nomem; | |
4210 | ||
45bf21a8 WY |
4211 | if (percpu_counter_init(&kvm_total_used_mmu_pages, 0)) |
4212 | goto nomem; | |
4213 | ||
3ee16c81 IE |
4214 | register_shrinker(&mmu_shrinker); |
4215 | ||
b5a33a75 AK |
4216 | return 0; |
4217 | ||
4218 | nomem: | |
3ee16c81 | 4219 | mmu_destroy_caches(); |
b5a33a75 AK |
4220 | return -ENOMEM; |
4221 | } | |
4222 | ||
3ad82a7e ZX |
4223 | /* |
4224 | * Caculate mmu pages needed for kvm. | |
4225 | */ | |
4226 | unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm) | |
4227 | { | |
3ad82a7e ZX |
4228 | unsigned int nr_mmu_pages; |
4229 | unsigned int nr_pages = 0; | |
bc6678a3 | 4230 | struct kvm_memslots *slots; |
be6ba0f0 | 4231 | struct kvm_memory_slot *memslot; |
3ad82a7e | 4232 | |
90d83dc3 LJ |
4233 | slots = kvm_memslots(kvm); |
4234 | ||
be6ba0f0 XG |
4235 | kvm_for_each_memslot(memslot, slots) |
4236 | nr_pages += memslot->npages; | |
3ad82a7e ZX |
4237 | |
4238 | nr_mmu_pages = nr_pages * KVM_PERMILLE_MMU_PAGES / 1000; | |
4239 | nr_mmu_pages = max(nr_mmu_pages, | |
4240 | (unsigned int) KVM_MIN_ALLOC_MMU_PAGES); | |
4241 | ||
4242 | return nr_mmu_pages; | |
4243 | } | |
4244 | ||
94d8b056 MT |
4245 | int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]) |
4246 | { | |
4247 | struct kvm_shadow_walk_iterator iterator; | |
c2a2ac2b | 4248 | u64 spte; |
94d8b056 MT |
4249 | int nr_sptes = 0; |
4250 | ||
c2a2ac2b XG |
4251 | walk_shadow_page_lockless_begin(vcpu); |
4252 | for_each_shadow_entry_lockless(vcpu, addr, iterator, spte) { | |
4253 | sptes[iterator.level-1] = spte; | |
94d8b056 | 4254 | nr_sptes++; |
c2a2ac2b | 4255 | if (!is_shadow_present_pte(spte)) |
94d8b056 MT |
4256 | break; |
4257 | } | |
c2a2ac2b | 4258 | walk_shadow_page_lockless_end(vcpu); |
94d8b056 MT |
4259 | |
4260 | return nr_sptes; | |
4261 | } | |
4262 | EXPORT_SYMBOL_GPL(kvm_mmu_get_spte_hierarchy); | |
4263 | ||
c42fffe3 XG |
4264 | void kvm_mmu_destroy(struct kvm_vcpu *vcpu) |
4265 | { | |
4266 | ASSERT(vcpu); | |
4267 | ||
4268 | destroy_kvm_mmu(vcpu); | |
4269 | free_mmu_pages(vcpu); | |
4270 | mmu_free_memory_caches(vcpu); | |
b034cf01 XG |
4271 | } |
4272 | ||
b034cf01 XG |
4273 | void kvm_mmu_module_exit(void) |
4274 | { | |
4275 | mmu_destroy_caches(); | |
4276 | percpu_counter_destroy(&kvm_total_used_mmu_pages); | |
4277 | unregister_shrinker(&mmu_shrinker); | |
c42fffe3 XG |
4278 | mmu_audit_disable(); |
4279 | } |