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authorAvi Kivity <avi@qumranet.com>2007-12-16 04:02:48 -0500
committerAvi Kivity <avi@qumranet.com>2008-01-30 11:01:18 -0500
commitedf884172e9828c6234b254208af04655855038d (patch)
treef5e5d1eecaed9737eced6ba60d09fe93149751c1 /drivers/kvm/paging_tmpl.h
parent9584bf2c93f56656dba0de8f6c75b54ca7995143 (diff)
KVM: Move arch dependent files to new directory arch/x86/kvm/
This paves the way for multiple architecture support. Note that while ioapic.c could potentially be shared with ia64, it is also moved. Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'drivers/kvm/paging_tmpl.h')
-rw-r--r--drivers/kvm/paging_tmpl.h461
1 files changed, 0 insertions, 461 deletions
diff --git a/drivers/kvm/paging_tmpl.h b/drivers/kvm/paging_tmpl.h
deleted file mode 100644
index 56b88f7e83ef..000000000000
--- a/drivers/kvm/paging_tmpl.h
+++ /dev/null
@@ -1,461 +0,0 @@
1/*
2 * Kernel-based Virtual Machine driver for Linux
3 *
4 * This module enables machines with Intel VT-x extensions to run virtual
5 * machines without emulation or binary translation.
6 *
7 * MMU support
8 *
9 * Copyright (C) 2006 Qumranet, Inc.
10 *
11 * Authors:
12 * Yaniv Kamay <yaniv@qumranet.com>
13 * Avi Kivity <avi@qumranet.com>
14 *
15 * This work is licensed under the terms of the GNU GPL, version 2. See
16 * the COPYING file in the top-level directory.
17 *
18 */
19
20/*
21 * We need the mmu code to access both 32-bit and 64-bit guest ptes,
22 * so the code in this file is compiled twice, once per pte size.
23 */
24
25#if PTTYPE == 64
26 #define pt_element_t u64
27 #define guest_walker guest_walker64
28 #define FNAME(name) paging##64_##name
29 #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK
30 #define PT_DIR_BASE_ADDR_MASK PT64_DIR_BASE_ADDR_MASK
31 #define PT_INDEX(addr, level) PT64_INDEX(addr, level)
32 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
33 #define PT_LEVEL_MASK(level) PT64_LEVEL_MASK(level)
34 #define PT_LEVEL_BITS PT64_LEVEL_BITS
35 #ifdef CONFIG_X86_64
36 #define PT_MAX_FULL_LEVELS 4
37 #define CMPXCHG cmpxchg
38 #else
39 #define CMPXCHG cmpxchg64
40 #define PT_MAX_FULL_LEVELS 2
41 #endif
42#elif PTTYPE == 32
43 #define pt_element_t u32
44 #define guest_walker guest_walker32
45 #define FNAME(name) paging##32_##name
46 #define PT_BASE_ADDR_MASK PT32_BASE_ADDR_MASK
47 #define PT_DIR_BASE_ADDR_MASK PT32_DIR_BASE_ADDR_MASK
48 #define PT_INDEX(addr, level) PT32_INDEX(addr, level)
49 #define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
50 #define PT_LEVEL_MASK(level) PT32_LEVEL_MASK(level)
51 #define PT_LEVEL_BITS PT32_LEVEL_BITS
52 #define PT_MAX_FULL_LEVELS 2
53 #define CMPXCHG cmpxchg
54#else
55 #error Invalid PTTYPE value
56#endif
57
58#define gpte_to_gfn FNAME(gpte_to_gfn)
59#define gpte_to_gfn_pde FNAME(gpte_to_gfn_pde)
60
61/*
62 * The guest_walker structure emulates the behavior of the hardware page
63 * table walker.
64 */
65struct guest_walker {
66 int level;
67 gfn_t table_gfn[PT_MAX_FULL_LEVELS];
68 pt_element_t ptes[PT_MAX_FULL_LEVELS];
69 gpa_t pte_gpa[PT_MAX_FULL_LEVELS];
70 unsigned pt_access;
71 unsigned pte_access;
72 gfn_t gfn;
73 u32 error_code;
74};
75
76static gfn_t gpte_to_gfn(pt_element_t gpte)
77{
78 return (gpte & PT_BASE_ADDR_MASK) >> PAGE_SHIFT;
79}
80
81static gfn_t gpte_to_gfn_pde(pt_element_t gpte)
82{
83 return (gpte & PT_DIR_BASE_ADDR_MASK) >> PAGE_SHIFT;
84}
85
86static bool FNAME(cmpxchg_gpte)(struct kvm *kvm,
87 gfn_t table_gfn, unsigned index,
88 pt_element_t orig_pte, pt_element_t new_pte)
89{
90 pt_element_t ret;
91 pt_element_t *table;
92 struct page *page;
93
94 page = gfn_to_page(kvm, table_gfn);
95 table = kmap_atomic(page, KM_USER0);
96
97 ret = CMPXCHG(&table[index], orig_pte, new_pte);
98
99 kunmap_atomic(table, KM_USER0);
100
101 kvm_release_page_dirty(page);
102
103 return (ret != orig_pte);
104}
105
106static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
107{
108 unsigned access;
109
110 access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK;
111#if PTTYPE == 64
112 if (is_nx(vcpu))
113 access &= ~(gpte >> PT64_NX_SHIFT);
114#endif
115 return access;
116}
117
118/*
119 * Fetch a guest pte for a guest virtual address
120 */
121static int FNAME(walk_addr)(struct guest_walker *walker,
122 struct kvm_vcpu *vcpu, gva_t addr,
123 int write_fault, int user_fault, int fetch_fault)
124{
125 pt_element_t pte;
126 gfn_t table_gfn;
127 unsigned index, pt_access, pte_access;
128 gpa_t pte_gpa;
129
130 pgprintk("%s: addr %lx\n", __FUNCTION__, addr);
131walk:
132 walker->level = vcpu->arch.mmu.root_level;
133 pte = vcpu->arch.cr3;
134#if PTTYPE == 64
135 if (!is_long_mode(vcpu)) {
136 pte = vcpu->arch.pdptrs[(addr >> 30) & 3];
137 if (!is_present_pte(pte))
138 goto not_present;
139 --walker->level;
140 }
141#endif
142 ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
143 (vcpu->cr3 & CR3_NONPAE_RESERVED_BITS) == 0);
144
145 pt_access = ACC_ALL;
146
147 for (;;) {
148 index = PT_INDEX(addr, walker->level);
149
150 table_gfn = gpte_to_gfn(pte);
151 pte_gpa = gfn_to_gpa(table_gfn);
152 pte_gpa += index * sizeof(pt_element_t);
153 walker->table_gfn[walker->level - 1] = table_gfn;
154 walker->pte_gpa[walker->level - 1] = pte_gpa;
155 pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__,
156 walker->level - 1, table_gfn);
157
158 kvm_read_guest(vcpu->kvm, pte_gpa, &pte, sizeof(pte));
159
160 if (!is_present_pte(pte))
161 goto not_present;
162
163 if (write_fault && !is_writeble_pte(pte))
164 if (user_fault || is_write_protection(vcpu))
165 goto access_error;
166
167 if (user_fault && !(pte & PT_USER_MASK))
168 goto access_error;
169
170#if PTTYPE == 64
171 if (fetch_fault && is_nx(vcpu) && (pte & PT64_NX_MASK))
172 goto access_error;
173#endif
174
175 if (!(pte & PT_ACCESSED_MASK)) {
176 mark_page_dirty(vcpu->kvm, table_gfn);
177 if (FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn,
178 index, pte, pte|PT_ACCESSED_MASK))
179 goto walk;
180 pte |= PT_ACCESSED_MASK;
181 }
182
183 pte_access = pt_access & FNAME(gpte_access)(vcpu, pte);
184
185 walker->ptes[walker->level - 1] = pte;
186
187 if (walker->level == PT_PAGE_TABLE_LEVEL) {
188 walker->gfn = gpte_to_gfn(pte);
189 break;
190 }
191
192 if (walker->level == PT_DIRECTORY_LEVEL
193 && (pte & PT_PAGE_SIZE_MASK)
194 && (PTTYPE == 64 || is_pse(vcpu))) {
195 walker->gfn = gpte_to_gfn_pde(pte);
196 walker->gfn += PT_INDEX(addr, PT_PAGE_TABLE_LEVEL);
197 if (PTTYPE == 32 && is_cpuid_PSE36())
198 walker->gfn += pse36_gfn_delta(pte);
199 break;
200 }
201
202 pt_access = pte_access;
203 --walker->level;
204 }
205
206 if (write_fault && !is_dirty_pte(pte)) {
207 bool ret;
208
209 mark_page_dirty(vcpu->kvm, table_gfn);
210 ret = FNAME(cmpxchg_gpte)(vcpu->kvm, table_gfn, index, pte,
211 pte|PT_DIRTY_MASK);
212 if (ret)
213 goto walk;
214 pte |= PT_DIRTY_MASK;
215 kvm_mmu_pte_write(vcpu, pte_gpa, (u8 *)&pte, sizeof(pte));
216 walker->ptes[walker->level - 1] = pte;
217 }
218
219 walker->pt_access = pt_access;
220 walker->pte_access = pte_access;
221 pgprintk("%s: pte %llx pte_access %x pt_access %x\n",
222 __FUNCTION__, (u64)pte, pt_access, pte_access);
223 return 1;
224
225not_present:
226 walker->error_code = 0;
227 goto err;
228
229access_error:
230 walker->error_code = PFERR_PRESENT_MASK;
231
232err:
233 if (write_fault)
234 walker->error_code |= PFERR_WRITE_MASK;
235 if (user_fault)
236 walker->error_code |= PFERR_USER_MASK;
237 if (fetch_fault)
238 walker->error_code |= PFERR_FETCH_MASK;
239 return 0;
240}
241
242static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *page,
243 u64 *spte, const void *pte, int bytes,
244 int offset_in_pte)
245{
246 pt_element_t gpte;
247 unsigned pte_access;
248
249 gpte = *(const pt_element_t *)pte;
250 if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {
251 if (!offset_in_pte && !is_present_pte(gpte))
252 set_shadow_pte(spte, shadow_notrap_nonpresent_pte);
253 return;
254 }
255 if (bytes < sizeof(pt_element_t))
256 return;
257 pgprintk("%s: gpte %llx spte %p\n", __FUNCTION__, (u64)gpte, spte);
258 pte_access = page->role.access & FNAME(gpte_access)(vcpu, gpte);
259 mmu_set_spte(vcpu, spte, page->role.access, pte_access, 0, 0,
260 gpte & PT_DIRTY_MASK, NULL, gpte_to_gfn(gpte));
261}
262
263/*
264 * Fetch a shadow pte for a specific level in the paging hierarchy.
265 */
266static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
267 struct guest_walker *walker,
268 int user_fault, int write_fault, int *ptwrite)
269{
270 hpa_t shadow_addr;
271 int level;
272 u64 *shadow_ent;
273 unsigned access = walker->pt_access;
274
275 if (!is_present_pte(walker->ptes[walker->level - 1]))
276 return NULL;
277
278 shadow_addr = vcpu->arch.mmu.root_hpa;
279 level = vcpu->arch.mmu.shadow_root_level;
280 if (level == PT32E_ROOT_LEVEL) {
281 shadow_addr = vcpu->arch.mmu.pae_root[(addr >> 30) & 3];
282 shadow_addr &= PT64_BASE_ADDR_MASK;
283 --level;
284 }
285
286 for (; ; level--) {
287 u32 index = SHADOW_PT_INDEX(addr, level);
288 struct kvm_mmu_page *shadow_page;
289 u64 shadow_pte;
290 int metaphysical;
291 gfn_t table_gfn;
292 bool new_page = 0;
293
294 shadow_ent = ((u64 *)__va(shadow_addr)) + index;
295 if (is_shadow_present_pte(*shadow_ent)) {
296 if (level == PT_PAGE_TABLE_LEVEL)
297 break;
298 shadow_addr = *shadow_ent & PT64_BASE_ADDR_MASK;
299 continue;
300 }
301
302 if (level == PT_PAGE_TABLE_LEVEL)
303 break;
304
305 if (level - 1 == PT_PAGE_TABLE_LEVEL
306 && walker->level == PT_DIRECTORY_LEVEL) {
307 metaphysical = 1;
308 if (!is_dirty_pte(walker->ptes[level - 1]))
309 access &= ~ACC_WRITE_MASK;
310 table_gfn = gpte_to_gfn(walker->ptes[level - 1]);
311 } else {
312 metaphysical = 0;
313 table_gfn = walker->table_gfn[level - 2];
314 }
315 shadow_page = kvm_mmu_get_page(vcpu, table_gfn, addr, level-1,
316 metaphysical, access,
317 shadow_ent, &new_page);
318 if (new_page && !metaphysical) {
319 pt_element_t curr_pte;
320 kvm_read_guest(vcpu->kvm, walker->pte_gpa[level - 2],
321 &curr_pte, sizeof(curr_pte));
322 if (curr_pte != walker->ptes[level - 2])
323 return NULL;
324 }
325 shadow_addr = __pa(shadow_page->spt);
326 shadow_pte = shadow_addr | PT_PRESENT_MASK | PT_ACCESSED_MASK
327 | PT_WRITABLE_MASK | PT_USER_MASK;
328 *shadow_ent = shadow_pte;
329 }
330
331 mmu_set_spte(vcpu, shadow_ent, access, walker->pte_access & access,
332 user_fault, write_fault,
333 walker->ptes[walker->level-1] & PT_DIRTY_MASK,
334 ptwrite, walker->gfn);
335
336 return shadow_ent;
337}
338
339/*
340 * Page fault handler. There are several causes for a page fault:
341 * - there is no shadow pte for the guest pte
342 * - write access through a shadow pte marked read only so that we can set
343 * the dirty bit
344 * - write access to a shadow pte marked read only so we can update the page
345 * dirty bitmap, when userspace requests it
346 * - mmio access; in this case we will never install a present shadow pte
347 * - normal guest page fault due to the guest pte marked not present, not
348 * writable, or not executable
349 *
350 * Returns: 1 if we need to emulate the instruction, 0 otherwise, or
351 * a negative value on error.
352 */
353static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr,
354 u32 error_code)
355{
356 int write_fault = error_code & PFERR_WRITE_MASK;
357 int user_fault = error_code & PFERR_USER_MASK;
358 int fetch_fault = error_code & PFERR_FETCH_MASK;
359 struct guest_walker walker;
360 u64 *shadow_pte;
361 int write_pt = 0;
362 int r;
363
364 pgprintk("%s: addr %lx err %x\n", __FUNCTION__, addr, error_code);
365 kvm_mmu_audit(vcpu, "pre page fault");
366
367 r = mmu_topup_memory_caches(vcpu);
368 if (r)
369 return r;
370
371 /*
372 * Look up the shadow pte for the faulting address.
373 */
374 r = FNAME(walk_addr)(&walker, vcpu, addr, write_fault, user_fault,
375 fetch_fault);
376
377 /*
378 * The page is not mapped by the guest. Let the guest handle it.
379 */
380 if (!r) {
381 pgprintk("%s: guest page fault\n", __FUNCTION__);
382 inject_page_fault(vcpu, addr, walker.error_code);
383 vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
384 return 0;
385 }
386
387 shadow_pte = FNAME(fetch)(vcpu, addr, &walker, user_fault, write_fault,
388 &write_pt);
389 pgprintk("%s: shadow pte %p %llx ptwrite %d\n", __FUNCTION__,
390 shadow_pte, *shadow_pte, write_pt);
391
392 if (!write_pt)
393 vcpu->arch.last_pt_write_count = 0; /* reset fork detector */
394
395 /*
396 * mmio: emulate if accessible, otherwise its a guest fault.
397 */
398 if (shadow_pte && is_io_pte(*shadow_pte))
399 return 1;
400
401 ++vcpu->stat.pf_fixed;
402 kvm_mmu_audit(vcpu, "post page fault (fixed)");
403
404 return write_pt;
405}
406
407static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr)
408{
409 struct guest_walker walker;
410 gpa_t gpa = UNMAPPED_GVA;
411 int r;
412
413 r = FNAME(walk_addr)(&walker, vcpu, vaddr, 0, 0, 0);
414
415 if (r) {
416 gpa = gfn_to_gpa(walker.gfn);
417 gpa |= vaddr & ~PAGE_MASK;
418 }
419
420 return gpa;
421}
422
423static void FNAME(prefetch_page)(struct kvm_vcpu *vcpu,
424 struct kvm_mmu_page *sp)
425{
426 int i, offset = 0;
427 pt_element_t *gpt;
428 struct page *page;
429
430 if (sp->role.metaphysical
431 || (PTTYPE == 32 && sp->role.level > PT_PAGE_TABLE_LEVEL)) {
432 nonpaging_prefetch_page(vcpu, sp);
433 return;
434 }
435
436 if (PTTYPE == 32)
437 offset = sp->role.quadrant << PT64_LEVEL_BITS;
438 page = gfn_to_page(vcpu->kvm, sp->gfn);
439 gpt = kmap_atomic(page, KM_USER0);
440 for (i = 0; i < PT64_ENT_PER_PAGE; ++i)
441 if (is_present_pte(gpt[offset + i]))
442 sp->spt[i] = shadow_trap_nonpresent_pte;
443 else
444 sp->spt[i] = shadow_notrap_nonpresent_pte;
445 kunmap_atomic(gpt, KM_USER0);
446 kvm_release_page_clean(page);
447}
448
449#undef pt_element_t
450#undef guest_walker
451#undef FNAME
452#undef PT_BASE_ADDR_MASK
453#undef PT_INDEX
454#undef SHADOW_PT_INDEX
455#undef PT_LEVEL_MASK
456#undef PT_DIR_BASE_ADDR_MASK
457#undef PT_LEVEL_BITS
458#undef PT_MAX_FULL_LEVELS
459#undef gpte_to_gfn
460#undef gpte_to_gfn_pde
461#undef CMPXCHG