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ac41aaee | 1 | // SPDX-License-Identifier: GPL-2.0 |
1e133ab2 MS |
2 | /* |
3 | * KVM guest address space mapping code | |
4 | * | |
5 | * Copyright IBM Corp. 2007, 2016 | |
6 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> | |
7 | */ | |
8 | ||
9 | #include <linux/kernel.h> | |
10 | #include <linux/mm.h> | |
11 | #include <linux/swap.h> | |
12 | #include <linux/smp.h> | |
13 | #include <linux/spinlock.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/swapops.h> | |
16 | #include <linux/ksm.h> | |
17 | #include <linux/mman.h> | |
18 | ||
19 | #include <asm/pgtable.h> | |
20 | #include <asm/pgalloc.h> | |
21 | #include <asm/gmap.h> | |
22 | #include <asm/tlb.h> | |
23 | ||
fd8d4e3a DH |
24 | #define GMAP_SHADOW_FAKE_TABLE 1ULL |
25 | ||
1e133ab2 | 26 | /** |
6ea427bb | 27 | * gmap_alloc - allocate and initialize a guest address space |
1e133ab2 | 28 | * @mm: pointer to the parent mm_struct |
9c650d09 | 29 | * @limit: maximum address of the gmap address space |
1e133ab2 MS |
30 | * |
31 | * Returns a guest address space structure. | |
32 | */ | |
6ea427bb | 33 | static struct gmap *gmap_alloc(unsigned long limit) |
1e133ab2 MS |
34 | { |
35 | struct gmap *gmap; | |
36 | struct page *page; | |
37 | unsigned long *table; | |
38 | unsigned long etype, atype; | |
39 | ||
f1c1174f HC |
40 | if (limit < _REGION3_SIZE) { |
41 | limit = _REGION3_SIZE - 1; | |
1e133ab2 MS |
42 | atype = _ASCE_TYPE_SEGMENT; |
43 | etype = _SEGMENT_ENTRY_EMPTY; | |
f1c1174f HC |
44 | } else if (limit < _REGION2_SIZE) { |
45 | limit = _REGION2_SIZE - 1; | |
1e133ab2 MS |
46 | atype = _ASCE_TYPE_REGION3; |
47 | etype = _REGION3_ENTRY_EMPTY; | |
f1c1174f HC |
48 | } else if (limit < _REGION1_SIZE) { |
49 | limit = _REGION1_SIZE - 1; | |
1e133ab2 MS |
50 | atype = _ASCE_TYPE_REGION2; |
51 | etype = _REGION2_ENTRY_EMPTY; | |
52 | } else { | |
53 | limit = -1UL; | |
54 | atype = _ASCE_TYPE_REGION1; | |
55 | etype = _REGION1_ENTRY_EMPTY; | |
56 | } | |
57 | gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL); | |
58 | if (!gmap) | |
59 | goto out; | |
60 | INIT_LIST_HEAD(&gmap->crst_list); | |
4be130a0 MS |
61 | INIT_LIST_HEAD(&gmap->children); |
62 | INIT_LIST_HEAD(&gmap->pt_list); | |
1e133ab2 MS |
63 | INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL); |
64 | INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC); | |
4be130a0 | 65 | INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC); |
1e133ab2 | 66 | spin_lock_init(&gmap->guest_table_lock); |
4be130a0 | 67 | spin_lock_init(&gmap->shadow_lock); |
6ea427bb | 68 | atomic_set(&gmap->ref_count, 1); |
f1c1174f | 69 | page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); |
1e133ab2 MS |
70 | if (!page) |
71 | goto out_free; | |
72 | page->index = 0; | |
73 | list_add(&page->lru, &gmap->crst_list); | |
74 | table = (unsigned long *) page_to_phys(page); | |
75 | crst_table_init(table, etype); | |
76 | gmap->table = table; | |
77 | gmap->asce = atype | _ASCE_TABLE_LENGTH | | |
78 | _ASCE_USER_BITS | __pa(table); | |
79 | gmap->asce_end = limit; | |
1e133ab2 MS |
80 | return gmap; |
81 | ||
82 | out_free: | |
83 | kfree(gmap); | |
84 | out: | |
85 | return NULL; | |
86 | } | |
6ea427bb MS |
87 | |
88 | /** | |
89 | * gmap_create - create a guest address space | |
90 | * @mm: pointer to the parent mm_struct | |
91 | * @limit: maximum size of the gmap address space | |
92 | * | |
93 | * Returns a guest address space structure. | |
94 | */ | |
95 | struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit) | |
96 | { | |
97 | struct gmap *gmap; | |
44b6cc81 | 98 | unsigned long gmap_asce; |
6ea427bb MS |
99 | |
100 | gmap = gmap_alloc(limit); | |
101 | if (!gmap) | |
102 | return NULL; | |
103 | gmap->mm = mm; | |
f28a4b4d | 104 | spin_lock(&mm->context.lock); |
6ea427bb | 105 | list_add_rcu(&gmap->list, &mm->context.gmap_list); |
44b6cc81 MS |
106 | if (list_is_singular(&mm->context.gmap_list)) |
107 | gmap_asce = gmap->asce; | |
108 | else | |
109 | gmap_asce = -1UL; | |
110 | WRITE_ONCE(mm->context.gmap_asce, gmap_asce); | |
f28a4b4d | 111 | spin_unlock(&mm->context.lock); |
6ea427bb MS |
112 | return gmap; |
113 | } | |
114 | EXPORT_SYMBOL_GPL(gmap_create); | |
1e133ab2 MS |
115 | |
116 | static void gmap_flush_tlb(struct gmap *gmap) | |
117 | { | |
118 | if (MACHINE_HAS_IDTE) | |
f0454029 | 119 | __tlb_flush_idte(gmap->asce); |
1e133ab2 MS |
120 | else |
121 | __tlb_flush_global(); | |
122 | } | |
123 | ||
124 | static void gmap_radix_tree_free(struct radix_tree_root *root) | |
125 | { | |
126 | struct radix_tree_iter iter; | |
127 | unsigned long indices[16]; | |
128 | unsigned long index; | |
d12a3d60 | 129 | void __rcu **slot; |
1e133ab2 MS |
130 | int i, nr; |
131 | ||
132 | /* A radix tree is freed by deleting all of its entries */ | |
133 | index = 0; | |
134 | do { | |
135 | nr = 0; | |
136 | radix_tree_for_each_slot(slot, root, &iter, index) { | |
137 | indices[nr] = iter.index; | |
138 | if (++nr == 16) | |
139 | break; | |
140 | } | |
141 | for (i = 0; i < nr; i++) { | |
142 | index = indices[i]; | |
143 | radix_tree_delete(root, index); | |
144 | } | |
145 | } while (nr > 0); | |
146 | } | |
147 | ||
4be130a0 MS |
148 | static void gmap_rmap_radix_tree_free(struct radix_tree_root *root) |
149 | { | |
150 | struct gmap_rmap *rmap, *rnext, *head; | |
151 | struct radix_tree_iter iter; | |
152 | unsigned long indices[16]; | |
153 | unsigned long index; | |
d12a3d60 | 154 | void __rcu **slot; |
4be130a0 MS |
155 | int i, nr; |
156 | ||
157 | /* A radix tree is freed by deleting all of its entries */ | |
158 | index = 0; | |
159 | do { | |
160 | nr = 0; | |
161 | radix_tree_for_each_slot(slot, root, &iter, index) { | |
162 | indices[nr] = iter.index; | |
163 | if (++nr == 16) | |
164 | break; | |
165 | } | |
166 | for (i = 0; i < nr; i++) { | |
167 | index = indices[i]; | |
168 | head = radix_tree_delete(root, index); | |
169 | gmap_for_each_rmap_safe(rmap, rnext, head) | |
170 | kfree(rmap); | |
171 | } | |
172 | } while (nr > 0); | |
173 | } | |
174 | ||
1e133ab2 MS |
175 | /** |
176 | * gmap_free - free a guest address space | |
177 | * @gmap: pointer to the guest address space structure | |
4be130a0 MS |
178 | * |
179 | * No locks required. There are no references to this gmap anymore. | |
1e133ab2 | 180 | */ |
6ea427bb | 181 | static void gmap_free(struct gmap *gmap) |
1e133ab2 MS |
182 | { |
183 | struct page *page, *next; | |
184 | ||
eea3678d DH |
185 | /* Flush tlb of all gmaps (if not already done for shadows) */ |
186 | if (!(gmap_is_shadow(gmap) && gmap->removed)) | |
187 | gmap_flush_tlb(gmap); | |
1e133ab2 MS |
188 | /* Free all segment & region tables. */ |
189 | list_for_each_entry_safe(page, next, &gmap->crst_list, lru) | |
f1c1174f | 190 | __free_pages(page, CRST_ALLOC_ORDER); |
1e133ab2 MS |
191 | gmap_radix_tree_free(&gmap->guest_to_host); |
192 | gmap_radix_tree_free(&gmap->host_to_guest); | |
4be130a0 MS |
193 | |
194 | /* Free additional data for a shadow gmap */ | |
195 | if (gmap_is_shadow(gmap)) { | |
196 | /* Free all page tables. */ | |
197 | list_for_each_entry_safe(page, next, &gmap->pt_list, lru) | |
198 | page_table_free_pgste(page); | |
199 | gmap_rmap_radix_tree_free(&gmap->host_to_rmap); | |
200 | /* Release reference to the parent */ | |
201 | gmap_put(gmap->parent); | |
202 | } | |
203 | ||
1e133ab2 MS |
204 | kfree(gmap); |
205 | } | |
6ea427bb MS |
206 | |
207 | /** | |
208 | * gmap_get - increase reference counter for guest address space | |
209 | * @gmap: pointer to the guest address space structure | |
210 | * | |
211 | * Returns the gmap pointer | |
212 | */ | |
213 | struct gmap *gmap_get(struct gmap *gmap) | |
214 | { | |
215 | atomic_inc(&gmap->ref_count); | |
216 | return gmap; | |
217 | } | |
218 | EXPORT_SYMBOL_GPL(gmap_get); | |
219 | ||
220 | /** | |
221 | * gmap_put - decrease reference counter for guest address space | |
222 | * @gmap: pointer to the guest address space structure | |
223 | * | |
224 | * If the reference counter reaches zero the guest address space is freed. | |
225 | */ | |
226 | void gmap_put(struct gmap *gmap) | |
227 | { | |
228 | if (atomic_dec_return(&gmap->ref_count) == 0) | |
229 | gmap_free(gmap); | |
230 | } | |
231 | EXPORT_SYMBOL_GPL(gmap_put); | |
232 | ||
233 | /** | |
234 | * gmap_remove - remove a guest address space but do not free it yet | |
235 | * @gmap: pointer to the guest address space structure | |
236 | */ | |
237 | void gmap_remove(struct gmap *gmap) | |
238 | { | |
4be130a0 | 239 | struct gmap *sg, *next; |
44b6cc81 | 240 | unsigned long gmap_asce; |
4be130a0 | 241 | |
4be130a0 MS |
242 | /* Remove all shadow gmaps linked to this gmap */ |
243 | if (!list_empty(&gmap->children)) { | |
244 | spin_lock(&gmap->shadow_lock); | |
245 | list_for_each_entry_safe(sg, next, &gmap->children, list) { | |
4be130a0 MS |
246 | list_del(&sg->list); |
247 | gmap_put(sg); | |
248 | } | |
249 | spin_unlock(&gmap->shadow_lock); | |
250 | } | |
6ea427bb | 251 | /* Remove gmap from the pre-mm list */ |
f28a4b4d | 252 | spin_lock(&gmap->mm->context.lock); |
6ea427bb | 253 | list_del_rcu(&gmap->list); |
44b6cc81 MS |
254 | if (list_empty(&gmap->mm->context.gmap_list)) |
255 | gmap_asce = 0; | |
256 | else if (list_is_singular(&gmap->mm->context.gmap_list)) | |
257 | gmap_asce = list_first_entry(&gmap->mm->context.gmap_list, | |
258 | struct gmap, list)->asce; | |
259 | else | |
260 | gmap_asce = -1UL; | |
261 | WRITE_ONCE(gmap->mm->context.gmap_asce, gmap_asce); | |
f28a4b4d | 262 | spin_unlock(&gmap->mm->context.lock); |
6ea427bb MS |
263 | synchronize_rcu(); |
264 | /* Put reference */ | |
265 | gmap_put(gmap); | |
266 | } | |
267 | EXPORT_SYMBOL_GPL(gmap_remove); | |
1e133ab2 MS |
268 | |
269 | /** | |
270 | * gmap_enable - switch primary space to the guest address space | |
271 | * @gmap: pointer to the guest address space structure | |
272 | */ | |
273 | void gmap_enable(struct gmap *gmap) | |
274 | { | |
275 | S390_lowcore.gmap = (unsigned long) gmap; | |
276 | } | |
277 | EXPORT_SYMBOL_GPL(gmap_enable); | |
278 | ||
279 | /** | |
280 | * gmap_disable - switch back to the standard primary address space | |
281 | * @gmap: pointer to the guest address space structure | |
282 | */ | |
283 | void gmap_disable(struct gmap *gmap) | |
284 | { | |
285 | S390_lowcore.gmap = 0UL; | |
286 | } | |
287 | EXPORT_SYMBOL_GPL(gmap_disable); | |
288 | ||
37d9df98 DH |
289 | /** |
290 | * gmap_get_enabled - get a pointer to the currently enabled gmap | |
291 | * | |
292 | * Returns a pointer to the currently enabled gmap. 0 if none is enabled. | |
293 | */ | |
294 | struct gmap *gmap_get_enabled(void) | |
295 | { | |
296 | return (struct gmap *) S390_lowcore.gmap; | |
297 | } | |
298 | EXPORT_SYMBOL_GPL(gmap_get_enabled); | |
299 | ||
1e133ab2 MS |
300 | /* |
301 | * gmap_alloc_table is assumed to be called with mmap_sem held | |
302 | */ | |
303 | static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, | |
304 | unsigned long init, unsigned long gaddr) | |
305 | { | |
306 | struct page *page; | |
307 | unsigned long *new; | |
308 | ||
309 | /* since we dont free the gmap table until gmap_free we can unlock */ | |
f1c1174f | 310 | page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); |
1e133ab2 MS |
311 | if (!page) |
312 | return -ENOMEM; | |
313 | new = (unsigned long *) page_to_phys(page); | |
314 | crst_table_init(new, init); | |
4be130a0 | 315 | spin_lock(&gmap->guest_table_lock); |
1e133ab2 MS |
316 | if (*table & _REGION_ENTRY_INVALID) { |
317 | list_add(&page->lru, &gmap->crst_list); | |
318 | *table = (unsigned long) new | _REGION_ENTRY_LENGTH | | |
319 | (*table & _REGION_ENTRY_TYPE_MASK); | |
320 | page->index = gaddr; | |
321 | page = NULL; | |
322 | } | |
4be130a0 | 323 | spin_unlock(&gmap->guest_table_lock); |
1e133ab2 | 324 | if (page) |
f1c1174f | 325 | __free_pages(page, CRST_ALLOC_ORDER); |
1e133ab2 MS |
326 | return 0; |
327 | } | |
328 | ||
329 | /** | |
330 | * __gmap_segment_gaddr - find virtual address from segment pointer | |
331 | * @entry: pointer to a segment table entry in the guest address space | |
332 | * | |
333 | * Returns the virtual address in the guest address space for the segment | |
334 | */ | |
335 | static unsigned long __gmap_segment_gaddr(unsigned long *entry) | |
336 | { | |
337 | struct page *page; | |
338 | unsigned long offset, mask; | |
339 | ||
340 | offset = (unsigned long) entry / sizeof(unsigned long); | |
341 | offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE; | |
342 | mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); | |
343 | page = virt_to_page((void *)((unsigned long) entry & mask)); | |
344 | return page->index + offset; | |
345 | } | |
346 | ||
347 | /** | |
348 | * __gmap_unlink_by_vmaddr - unlink a single segment via a host address | |
349 | * @gmap: pointer to the guest address space structure | |
350 | * @vmaddr: address in the host process address space | |
351 | * | |
352 | * Returns 1 if a TLB flush is required | |
353 | */ | |
354 | static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr) | |
355 | { | |
356 | unsigned long *entry; | |
357 | int flush = 0; | |
358 | ||
4be130a0 | 359 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
360 | spin_lock(&gmap->guest_table_lock); |
361 | entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT); | |
362 | if (entry) { | |
54397bb0 DD |
363 | flush = (*entry != _SEGMENT_ENTRY_EMPTY); |
364 | *entry = _SEGMENT_ENTRY_EMPTY; | |
1e133ab2 MS |
365 | } |
366 | spin_unlock(&gmap->guest_table_lock); | |
367 | return flush; | |
368 | } | |
369 | ||
370 | /** | |
371 | * __gmap_unmap_by_gaddr - unmap a single segment via a guest address | |
372 | * @gmap: pointer to the guest address space structure | |
373 | * @gaddr: address in the guest address space | |
374 | * | |
375 | * Returns 1 if a TLB flush is required | |
376 | */ | |
377 | static int __gmap_unmap_by_gaddr(struct gmap *gmap, unsigned long gaddr) | |
378 | { | |
379 | unsigned long vmaddr; | |
380 | ||
381 | vmaddr = (unsigned long) radix_tree_delete(&gmap->guest_to_host, | |
382 | gaddr >> PMD_SHIFT); | |
383 | return vmaddr ? __gmap_unlink_by_vmaddr(gmap, vmaddr) : 0; | |
384 | } | |
385 | ||
386 | /** | |
387 | * gmap_unmap_segment - unmap segment from the guest address space | |
388 | * @gmap: pointer to the guest address space structure | |
389 | * @to: address in the guest address space | |
390 | * @len: length of the memory area to unmap | |
391 | * | |
392 | * Returns 0 if the unmap succeeded, -EINVAL if not. | |
393 | */ | |
394 | int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len) | |
395 | { | |
396 | unsigned long off; | |
397 | int flush; | |
398 | ||
4be130a0 | 399 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
400 | if ((to | len) & (PMD_SIZE - 1)) |
401 | return -EINVAL; | |
402 | if (len == 0 || to + len < to) | |
403 | return -EINVAL; | |
404 | ||
405 | flush = 0; | |
406 | down_write(&gmap->mm->mmap_sem); | |
407 | for (off = 0; off < len; off += PMD_SIZE) | |
408 | flush |= __gmap_unmap_by_gaddr(gmap, to + off); | |
409 | up_write(&gmap->mm->mmap_sem); | |
410 | if (flush) | |
411 | gmap_flush_tlb(gmap); | |
412 | return 0; | |
413 | } | |
414 | EXPORT_SYMBOL_GPL(gmap_unmap_segment); | |
415 | ||
416 | /** | |
417 | * gmap_map_segment - map a segment to the guest address space | |
418 | * @gmap: pointer to the guest address space structure | |
419 | * @from: source address in the parent address space | |
420 | * @to: target address in the guest address space | |
421 | * @len: length of the memory area to map | |
422 | * | |
423 | * Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not. | |
424 | */ | |
425 | int gmap_map_segment(struct gmap *gmap, unsigned long from, | |
426 | unsigned long to, unsigned long len) | |
427 | { | |
428 | unsigned long off; | |
429 | int flush; | |
430 | ||
4be130a0 | 431 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
432 | if ((from | to | len) & (PMD_SIZE - 1)) |
433 | return -EINVAL; | |
434 | if (len == 0 || from + len < from || to + len < to || | |
ee71d16d | 435 | from + len - 1 > TASK_SIZE_MAX || to + len - 1 > gmap->asce_end) |
1e133ab2 MS |
436 | return -EINVAL; |
437 | ||
438 | flush = 0; | |
439 | down_write(&gmap->mm->mmap_sem); | |
440 | for (off = 0; off < len; off += PMD_SIZE) { | |
441 | /* Remove old translation */ | |
442 | flush |= __gmap_unmap_by_gaddr(gmap, to + off); | |
443 | /* Store new translation */ | |
444 | if (radix_tree_insert(&gmap->guest_to_host, | |
445 | (to + off) >> PMD_SHIFT, | |
446 | (void *) from + off)) | |
447 | break; | |
448 | } | |
449 | up_write(&gmap->mm->mmap_sem); | |
450 | if (flush) | |
451 | gmap_flush_tlb(gmap); | |
452 | if (off >= len) | |
453 | return 0; | |
454 | gmap_unmap_segment(gmap, to, len); | |
455 | return -ENOMEM; | |
456 | } | |
457 | EXPORT_SYMBOL_GPL(gmap_map_segment); | |
458 | ||
459 | /** | |
460 | * __gmap_translate - translate a guest address to a user space address | |
461 | * @gmap: pointer to guest mapping meta data structure | |
462 | * @gaddr: guest address | |
463 | * | |
464 | * Returns user space address which corresponds to the guest address or | |
465 | * -EFAULT if no such mapping exists. | |
466 | * This function does not establish potentially missing page table entries. | |
467 | * The mmap_sem of the mm that belongs to the address space must be held | |
468 | * when this function gets called. | |
4be130a0 MS |
469 | * |
470 | * Note: Can also be called for shadow gmaps. | |
1e133ab2 MS |
471 | */ |
472 | unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr) | |
473 | { | |
474 | unsigned long vmaddr; | |
475 | ||
476 | vmaddr = (unsigned long) | |
477 | radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT); | |
4be130a0 | 478 | /* Note: guest_to_host is empty for a shadow gmap */ |
1e133ab2 MS |
479 | return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT; |
480 | } | |
481 | EXPORT_SYMBOL_GPL(__gmap_translate); | |
482 | ||
483 | /** | |
484 | * gmap_translate - translate a guest address to a user space address | |
485 | * @gmap: pointer to guest mapping meta data structure | |
486 | * @gaddr: guest address | |
487 | * | |
488 | * Returns user space address which corresponds to the guest address or | |
489 | * -EFAULT if no such mapping exists. | |
490 | * This function does not establish potentially missing page table entries. | |
491 | */ | |
492 | unsigned long gmap_translate(struct gmap *gmap, unsigned long gaddr) | |
493 | { | |
494 | unsigned long rc; | |
495 | ||
496 | down_read(&gmap->mm->mmap_sem); | |
497 | rc = __gmap_translate(gmap, gaddr); | |
498 | up_read(&gmap->mm->mmap_sem); | |
499 | return rc; | |
500 | } | |
501 | EXPORT_SYMBOL_GPL(gmap_translate); | |
502 | ||
503 | /** | |
504 | * gmap_unlink - disconnect a page table from the gmap shadow tables | |
505 | * @gmap: pointer to guest mapping meta data structure | |
506 | * @table: pointer to the host page table | |
507 | * @vmaddr: vm address associated with the host page table | |
508 | */ | |
509 | void gmap_unlink(struct mm_struct *mm, unsigned long *table, | |
510 | unsigned long vmaddr) | |
511 | { | |
512 | struct gmap *gmap; | |
513 | int flush; | |
514 | ||
8ecb1a59 MS |
515 | rcu_read_lock(); |
516 | list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { | |
1e133ab2 MS |
517 | flush = __gmap_unlink_by_vmaddr(gmap, vmaddr); |
518 | if (flush) | |
519 | gmap_flush_tlb(gmap); | |
520 | } | |
8ecb1a59 | 521 | rcu_read_unlock(); |
1e133ab2 MS |
522 | } |
523 | ||
524 | /** | |
525 | * gmap_link - set up shadow page tables to connect a host to a guest address | |
526 | * @gmap: pointer to guest mapping meta data structure | |
527 | * @gaddr: guest address | |
528 | * @vmaddr: vm address | |
529 | * | |
530 | * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT | |
531 | * if the vm address is already mapped to a different guest segment. | |
532 | * The mmap_sem of the mm that belongs to the address space must be held | |
533 | * when this function gets called. | |
534 | */ | |
535 | int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) | |
536 | { | |
537 | struct mm_struct *mm; | |
538 | unsigned long *table; | |
539 | spinlock_t *ptl; | |
540 | pgd_t *pgd; | |
1aea9b3f | 541 | p4d_t *p4d; |
1e133ab2 MS |
542 | pud_t *pud; |
543 | pmd_t *pmd; | |
544 | int rc; | |
545 | ||
4be130a0 | 546 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
547 | /* Create higher level tables in the gmap page table */ |
548 | table = gmap->table; | |
549 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) { | |
f1c1174f | 550 | table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT; |
1e133ab2 MS |
551 | if ((*table & _REGION_ENTRY_INVALID) && |
552 | gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY, | |
f1c1174f | 553 | gaddr & _REGION1_MASK)) |
1e133ab2 MS |
554 | return -ENOMEM; |
555 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
556 | } | |
557 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION2) { | |
f1c1174f | 558 | table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT; |
1e133ab2 MS |
559 | if ((*table & _REGION_ENTRY_INVALID) && |
560 | gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY, | |
f1c1174f | 561 | gaddr & _REGION2_MASK)) |
1e133ab2 MS |
562 | return -ENOMEM; |
563 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
564 | } | |
565 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION3) { | |
f1c1174f | 566 | table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT; |
1e133ab2 MS |
567 | if ((*table & _REGION_ENTRY_INVALID) && |
568 | gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY, | |
f1c1174f | 569 | gaddr & _REGION3_MASK)) |
1e133ab2 MS |
570 | return -ENOMEM; |
571 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
572 | } | |
f1c1174f | 573 | table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT; |
1e133ab2 MS |
574 | /* Walk the parent mm page table */ |
575 | mm = gmap->mm; | |
576 | pgd = pgd_offset(mm, vmaddr); | |
577 | VM_BUG_ON(pgd_none(*pgd)); | |
1aea9b3f MS |
578 | p4d = p4d_offset(pgd, vmaddr); |
579 | VM_BUG_ON(p4d_none(*p4d)); | |
580 | pud = pud_offset(p4d, vmaddr); | |
1e133ab2 | 581 | VM_BUG_ON(pud_none(*pud)); |
d08de8e2 GS |
582 | /* large puds cannot yet be handled */ |
583 | if (pud_large(*pud)) | |
584 | return -EFAULT; | |
1e133ab2 MS |
585 | pmd = pmd_offset(pud, vmaddr); |
586 | VM_BUG_ON(pmd_none(*pmd)); | |
587 | /* large pmds cannot yet be handled */ | |
588 | if (pmd_large(*pmd)) | |
589 | return -EFAULT; | |
590 | /* Link gmap segment table entry location to page table. */ | |
591 | rc = radix_tree_preload(GFP_KERNEL); | |
592 | if (rc) | |
593 | return rc; | |
594 | ptl = pmd_lock(mm, pmd); | |
595 | spin_lock(&gmap->guest_table_lock); | |
54397bb0 | 596 | if (*table == _SEGMENT_ENTRY_EMPTY) { |
1e133ab2 MS |
597 | rc = radix_tree_insert(&gmap->host_to_guest, |
598 | vmaddr >> PMD_SHIFT, table); | |
599 | if (!rc) | |
600 | *table = pmd_val(*pmd); | |
601 | } else | |
602 | rc = 0; | |
603 | spin_unlock(&gmap->guest_table_lock); | |
604 | spin_unlock(ptl); | |
605 | radix_tree_preload_end(); | |
606 | return rc; | |
607 | } | |
608 | ||
609 | /** | |
610 | * gmap_fault - resolve a fault on a guest address | |
611 | * @gmap: pointer to guest mapping meta data structure | |
612 | * @gaddr: guest address | |
613 | * @fault_flags: flags to pass down to handle_mm_fault() | |
614 | * | |
615 | * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT | |
616 | * if the vm address is already mapped to a different guest segment. | |
617 | */ | |
618 | int gmap_fault(struct gmap *gmap, unsigned long gaddr, | |
619 | unsigned int fault_flags) | |
620 | { | |
621 | unsigned long vmaddr; | |
622 | int rc; | |
623 | bool unlocked; | |
624 | ||
625 | down_read(&gmap->mm->mmap_sem); | |
626 | ||
627 | retry: | |
628 | unlocked = false; | |
629 | vmaddr = __gmap_translate(gmap, gaddr); | |
630 | if (IS_ERR_VALUE(vmaddr)) { | |
631 | rc = vmaddr; | |
632 | goto out_up; | |
633 | } | |
634 | if (fixup_user_fault(current, gmap->mm, vmaddr, fault_flags, | |
635 | &unlocked)) { | |
636 | rc = -EFAULT; | |
637 | goto out_up; | |
638 | } | |
639 | /* | |
640 | * In the case that fixup_user_fault unlocked the mmap_sem during | |
641 | * faultin redo __gmap_translate to not race with a map/unmap_segment. | |
642 | */ | |
643 | if (unlocked) | |
644 | goto retry; | |
645 | ||
646 | rc = __gmap_link(gmap, gaddr, vmaddr); | |
647 | out_up: | |
648 | up_read(&gmap->mm->mmap_sem); | |
649 | return rc; | |
650 | } | |
651 | EXPORT_SYMBOL_GPL(gmap_fault); | |
652 | ||
653 | /* | |
654 | * this function is assumed to be called with mmap_sem held | |
655 | */ | |
656 | void __gmap_zap(struct gmap *gmap, unsigned long gaddr) | |
657 | { | |
658 | unsigned long vmaddr; | |
659 | spinlock_t *ptl; | |
660 | pte_t *ptep; | |
661 | ||
662 | /* Find the vm address for the guest address */ | |
663 | vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host, | |
664 | gaddr >> PMD_SHIFT); | |
665 | if (vmaddr) { | |
666 | vmaddr |= gaddr & ~PMD_MASK; | |
667 | /* Get pointer to the page table entry */ | |
668 | ptep = get_locked_pte(gmap->mm, vmaddr, &ptl); | |
669 | if (likely(ptep)) | |
670 | ptep_zap_unused(gmap->mm, vmaddr, ptep, 0); | |
671 | pte_unmap_unlock(ptep, ptl); | |
672 | } | |
673 | } | |
674 | EXPORT_SYMBOL_GPL(__gmap_zap); | |
675 | ||
676 | void gmap_discard(struct gmap *gmap, unsigned long from, unsigned long to) | |
677 | { | |
678 | unsigned long gaddr, vmaddr, size; | |
679 | struct vm_area_struct *vma; | |
680 | ||
681 | down_read(&gmap->mm->mmap_sem); | |
682 | for (gaddr = from; gaddr < to; | |
683 | gaddr = (gaddr + PMD_SIZE) & PMD_MASK) { | |
684 | /* Find the vm address for the guest address */ | |
685 | vmaddr = (unsigned long) | |
686 | radix_tree_lookup(&gmap->guest_to_host, | |
687 | gaddr >> PMD_SHIFT); | |
688 | if (!vmaddr) | |
689 | continue; | |
690 | vmaddr |= gaddr & ~PMD_MASK; | |
691 | /* Find vma in the parent mm */ | |
692 | vma = find_vma(gmap->mm, vmaddr); | |
693 | size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK)); | |
ecf1385d | 694 | zap_page_range(vma, vmaddr, size); |
1e133ab2 MS |
695 | } |
696 | up_read(&gmap->mm->mmap_sem); | |
697 | } | |
698 | EXPORT_SYMBOL_GPL(gmap_discard); | |
699 | ||
700 | static LIST_HEAD(gmap_notifier_list); | |
701 | static DEFINE_SPINLOCK(gmap_notifier_lock); | |
702 | ||
703 | /** | |
b2d73b2a | 704 | * gmap_register_pte_notifier - register a pte invalidation callback |
1e133ab2 MS |
705 | * @nb: pointer to the gmap notifier block |
706 | */ | |
b2d73b2a | 707 | void gmap_register_pte_notifier(struct gmap_notifier *nb) |
1e133ab2 MS |
708 | { |
709 | spin_lock(&gmap_notifier_lock); | |
8ecb1a59 | 710 | list_add_rcu(&nb->list, &gmap_notifier_list); |
1e133ab2 MS |
711 | spin_unlock(&gmap_notifier_lock); |
712 | } | |
b2d73b2a | 713 | EXPORT_SYMBOL_GPL(gmap_register_pte_notifier); |
1e133ab2 MS |
714 | |
715 | /** | |
b2d73b2a | 716 | * gmap_unregister_pte_notifier - remove a pte invalidation callback |
1e133ab2 MS |
717 | * @nb: pointer to the gmap notifier block |
718 | */ | |
b2d73b2a | 719 | void gmap_unregister_pte_notifier(struct gmap_notifier *nb) |
1e133ab2 MS |
720 | { |
721 | spin_lock(&gmap_notifier_lock); | |
8ecb1a59 | 722 | list_del_rcu(&nb->list); |
1e133ab2 | 723 | spin_unlock(&gmap_notifier_lock); |
8ecb1a59 | 724 | synchronize_rcu(); |
1e133ab2 | 725 | } |
b2d73b2a | 726 | EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier); |
1e133ab2 | 727 | |
414d3b07 MS |
728 | /** |
729 | * gmap_call_notifier - call all registered invalidation callbacks | |
730 | * @gmap: pointer to guest mapping meta data structure | |
731 | * @start: start virtual address in the guest address space | |
732 | * @end: end virtual address in the guest address space | |
733 | */ | |
734 | static void gmap_call_notifier(struct gmap *gmap, unsigned long start, | |
735 | unsigned long end) | |
736 | { | |
737 | struct gmap_notifier *nb; | |
738 | ||
739 | list_for_each_entry(nb, &gmap_notifier_list, list) | |
740 | nb->notifier_call(gmap, start, end); | |
741 | } | |
742 | ||
1e133ab2 | 743 | /** |
b2d73b2a MS |
744 | * gmap_table_walk - walk the gmap page tables |
745 | * @gmap: pointer to guest mapping meta data structure | |
746 | * @gaddr: virtual address in the guest address space | |
4be130a0 MS |
747 | * @level: page table level to stop at |
748 | * | |
749 | * Returns a table entry pointer for the given guest address and @level | |
750 | * @level=0 : returns a pointer to a page table table entry (or NULL) | |
751 | * @level=1 : returns a pointer to a segment table entry (or NULL) | |
752 | * @level=2 : returns a pointer to a region-3 table entry (or NULL) | |
753 | * @level=3 : returns a pointer to a region-2 table entry (or NULL) | |
754 | * @level=4 : returns a pointer to a region-1 table entry (or NULL) | |
755 | * | |
756 | * Returns NULL if the gmap page tables could not be walked to the | |
757 | * requested level. | |
b2d73b2a | 758 | * |
4be130a0 | 759 | * Note: Can also be called for shadow gmaps. |
b2d73b2a MS |
760 | */ |
761 | static inline unsigned long *gmap_table_walk(struct gmap *gmap, | |
4be130a0 | 762 | unsigned long gaddr, int level) |
b2d73b2a MS |
763 | { |
764 | unsigned long *table; | |
765 | ||
4be130a0 MS |
766 | if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4)) |
767 | return NULL; | |
768 | if (gmap_is_shadow(gmap) && gmap->removed) | |
769 | return NULL; | |
770 | if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11))) | |
771 | return NULL; | |
b2d73b2a MS |
772 | table = gmap->table; |
773 | switch (gmap->asce & _ASCE_TYPE_MASK) { | |
774 | case _ASCE_TYPE_REGION1: | |
f1c1174f | 775 | table += (gaddr & _REGION1_INDEX) >> _REGION1_SHIFT; |
4be130a0 MS |
776 | if (level == 4) |
777 | break; | |
b2d73b2a MS |
778 | if (*table & _REGION_ENTRY_INVALID) |
779 | return NULL; | |
780 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
781 | /* Fallthrough */ | |
782 | case _ASCE_TYPE_REGION2: | |
f1c1174f | 783 | table += (gaddr & _REGION2_INDEX) >> _REGION2_SHIFT; |
4be130a0 MS |
784 | if (level == 3) |
785 | break; | |
b2d73b2a MS |
786 | if (*table & _REGION_ENTRY_INVALID) |
787 | return NULL; | |
788 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
789 | /* Fallthrough */ | |
790 | case _ASCE_TYPE_REGION3: | |
f1c1174f | 791 | table += (gaddr & _REGION3_INDEX) >> _REGION3_SHIFT; |
4be130a0 MS |
792 | if (level == 2) |
793 | break; | |
b2d73b2a MS |
794 | if (*table & _REGION_ENTRY_INVALID) |
795 | return NULL; | |
796 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
797 | /* Fallthrough */ | |
798 | case _ASCE_TYPE_SEGMENT: | |
f1c1174f | 799 | table += (gaddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT; |
4be130a0 MS |
800 | if (level == 1) |
801 | break; | |
802 | if (*table & _REGION_ENTRY_INVALID) | |
803 | return NULL; | |
804 | table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); | |
f1c1174f | 805 | table += (gaddr & _PAGE_INDEX) >> _PAGE_SHIFT; |
b2d73b2a MS |
806 | } |
807 | return table; | |
808 | } | |
809 | ||
810 | /** | |
811 | * gmap_pte_op_walk - walk the gmap page table, get the page table lock | |
812 | * and return the pte pointer | |
813 | * @gmap: pointer to guest mapping meta data structure | |
814 | * @gaddr: virtual address in the guest address space | |
815 | * @ptl: pointer to the spinlock pointer | |
816 | * | |
817 | * Returns a pointer to the locked pte for a guest address, or NULL | |
4be130a0 MS |
818 | * |
819 | * Note: Can also be called for shadow gmaps. | |
b2d73b2a MS |
820 | */ |
821 | static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr, | |
822 | spinlock_t **ptl) | |
823 | { | |
824 | unsigned long *table; | |
825 | ||
4be130a0 MS |
826 | if (gmap_is_shadow(gmap)) |
827 | spin_lock(&gmap->guest_table_lock); | |
b2d73b2a | 828 | /* Walk the gmap page table, lock and get pte pointer */ |
4be130a0 MS |
829 | table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */ |
830 | if (!table || *table & _SEGMENT_ENTRY_INVALID) { | |
831 | if (gmap_is_shadow(gmap)) | |
832 | spin_unlock(&gmap->guest_table_lock); | |
b2d73b2a | 833 | return NULL; |
4be130a0 MS |
834 | } |
835 | if (gmap_is_shadow(gmap)) { | |
836 | *ptl = &gmap->guest_table_lock; | |
837 | return pte_offset_map((pmd_t *) table, gaddr); | |
838 | } | |
b2d73b2a MS |
839 | return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl); |
840 | } | |
841 | ||
842 | /** | |
843 | * gmap_pte_op_fixup - force a page in and connect the gmap page table | |
844 | * @gmap: pointer to guest mapping meta data structure | |
845 | * @gaddr: virtual address in the guest address space | |
846 | * @vmaddr: address in the host process address space | |
01f71917 | 847 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
b2d73b2a MS |
848 | * |
849 | * Returns 0 if the caller can retry __gmap_translate (might fail again), | |
850 | * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing | |
851 | * up or connecting the gmap page table. | |
852 | */ | |
853 | static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr, | |
01f71917 | 854 | unsigned long vmaddr, int prot) |
b2d73b2a MS |
855 | { |
856 | struct mm_struct *mm = gmap->mm; | |
01f71917 | 857 | unsigned int fault_flags; |
b2d73b2a MS |
858 | bool unlocked = false; |
859 | ||
4be130a0 | 860 | BUG_ON(gmap_is_shadow(gmap)); |
01f71917 DH |
861 | fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0; |
862 | if (fixup_user_fault(current, mm, vmaddr, fault_flags, &unlocked)) | |
b2d73b2a MS |
863 | return -EFAULT; |
864 | if (unlocked) | |
865 | /* lost mmap_sem, caller has to retry __gmap_translate */ | |
866 | return 0; | |
867 | /* Connect the page tables */ | |
868 | return __gmap_link(gmap, gaddr, vmaddr); | |
1e133ab2 | 869 | } |
1e133ab2 MS |
870 | |
871 | /** | |
b2d73b2a MS |
872 | * gmap_pte_op_end - release the page table lock |
873 | * @ptl: pointer to the spinlock pointer | |
874 | */ | |
875 | static void gmap_pte_op_end(spinlock_t *ptl) | |
876 | { | |
877 | spin_unlock(ptl); | |
878 | } | |
879 | ||
4be130a0 MS |
880 | /* |
881 | * gmap_protect_range - remove access rights to memory and set pgste bits | |
1e133ab2 MS |
882 | * @gmap: pointer to guest mapping meta data structure |
883 | * @gaddr: virtual address in the guest address space | |
884 | * @len: size of area | |
4be130a0 MS |
885 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
886 | * @bits: pgste notification bits to set | |
887 | * | |
888 | * Returns 0 if successfully protected, -ENOMEM if out of memory and | |
889 | * -EFAULT if gaddr is invalid (or mapping for shadows is missing). | |
890 | * | |
891 | * Called with sg->mm->mmap_sem in read. | |
1e133ab2 | 892 | * |
4be130a0 | 893 | * Note: Can also be called for shadow gmaps. |
1e133ab2 | 894 | */ |
4be130a0 MS |
895 | static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr, |
896 | unsigned long len, int prot, unsigned long bits) | |
1e133ab2 | 897 | { |
4be130a0 | 898 | unsigned long vmaddr; |
1e133ab2 MS |
899 | spinlock_t *ptl; |
900 | pte_t *ptep; | |
4be130a0 MS |
901 | int rc; |
902 | ||
903 | while (len) { | |
904 | rc = -EAGAIN; | |
905 | ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); | |
906 | if (ptep) { | |
907 | rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits); | |
908 | gmap_pte_op_end(ptl); | |
909 | } | |
910 | if (rc) { | |
911 | vmaddr = __gmap_translate(gmap, gaddr); | |
912 | if (IS_ERR_VALUE(vmaddr)) | |
913 | return vmaddr; | |
01f71917 | 914 | rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot); |
4be130a0 MS |
915 | if (rc) |
916 | return rc; | |
917 | continue; | |
918 | } | |
919 | gaddr += PAGE_SIZE; | |
920 | len -= PAGE_SIZE; | |
921 | } | |
922 | return 0; | |
923 | } | |
1e133ab2 | 924 | |
b2d73b2a MS |
925 | /** |
926 | * gmap_mprotect_notify - change access rights for a range of ptes and | |
927 | * call the notifier if any pte changes again | |
1e133ab2 MS |
928 | * @gmap: pointer to guest mapping meta data structure |
929 | * @gaddr: virtual address in the guest address space | |
930 | * @len: size of area | |
b2d73b2a | 931 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
1e133ab2 | 932 | * |
b2d73b2a MS |
933 | * Returns 0 if for each page in the given range a gmap mapping exists, |
934 | * the new access rights could be set and the notifier could be armed. | |
935 | * If the gmap mapping is missing for one or more pages -EFAULT is | |
936 | * returned. If no memory could be allocated -ENOMEM is returned. | |
937 | * This function establishes missing page table entries. | |
1e133ab2 | 938 | */ |
b2d73b2a MS |
939 | int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr, |
940 | unsigned long len, int prot) | |
1e133ab2 | 941 | { |
4be130a0 | 942 | int rc; |
1e133ab2 | 943 | |
4be130a0 | 944 | if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap)) |
1e133ab2 | 945 | return -EINVAL; |
b2d73b2a | 946 | if (!MACHINE_HAS_ESOP && prot == PROT_READ) |
1e133ab2 MS |
947 | return -EINVAL; |
948 | down_read(&gmap->mm->mmap_sem); | |
4be130a0 MS |
949 | rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT); |
950 | up_read(&gmap->mm->mmap_sem); | |
951 | return rc; | |
952 | } | |
953 | EXPORT_SYMBOL_GPL(gmap_mprotect_notify); | |
954 | ||
955 | /** | |
956 | * gmap_read_table - get an unsigned long value from a guest page table using | |
957 | * absolute addressing, without marking the page referenced. | |
958 | * @gmap: pointer to guest mapping meta data structure | |
959 | * @gaddr: virtual address in the guest address space | |
960 | * @val: pointer to the unsigned long value to return | |
961 | * | |
962 | * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT | |
963 | * if reading using the virtual address failed. | |
964 | * | |
965 | * Called with gmap->mm->mmap_sem in read. | |
966 | */ | |
967 | int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val) | |
968 | { | |
969 | unsigned long address, vmaddr; | |
970 | spinlock_t *ptl; | |
971 | pte_t *ptep, pte; | |
972 | int rc; | |
973 | ||
974 | while (1) { | |
b2d73b2a MS |
975 | rc = -EAGAIN; |
976 | ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); | |
977 | if (ptep) { | |
4be130a0 MS |
978 | pte = *ptep; |
979 | if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) { | |
980 | address = pte_val(pte) & PAGE_MASK; | |
981 | address += gaddr & ~PAGE_MASK; | |
982 | *val = *(unsigned long *) address; | |
983 | pte_val(*ptep) |= _PAGE_YOUNG; | |
984 | /* Do *NOT* clear the _PAGE_INVALID bit! */ | |
985 | rc = 0; | |
986 | } | |
b2d73b2a | 987 | gmap_pte_op_end(ptl); |
1e133ab2 | 988 | } |
4be130a0 MS |
989 | if (!rc) |
990 | break; | |
991 | vmaddr = __gmap_translate(gmap, gaddr); | |
992 | if (IS_ERR_VALUE(vmaddr)) { | |
993 | rc = vmaddr; | |
1e133ab2 MS |
994 | break; |
995 | } | |
01f71917 | 996 | rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ); |
1e133ab2 MS |
997 | if (rc) |
998 | break; | |
1e133ab2 | 999 | } |
1e133ab2 MS |
1000 | return rc; |
1001 | } | |
4be130a0 | 1002 | EXPORT_SYMBOL_GPL(gmap_read_table); |
1e133ab2 MS |
1003 | |
1004 | /** | |
4be130a0 MS |
1005 | * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree |
1006 | * @sg: pointer to the shadow guest address space structure | |
1007 | * @vmaddr: vm address associated with the rmap | |
1008 | * @rmap: pointer to the rmap structure | |
1e133ab2 | 1009 | * |
4be130a0 | 1010 | * Called with the sg->guest_table_lock |
1e133ab2 | 1011 | */ |
4be130a0 MS |
1012 | static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr, |
1013 | struct gmap_rmap *rmap) | |
1e133ab2 | 1014 | { |
d12a3d60 | 1015 | void __rcu **slot; |
1e133ab2 | 1016 | |
4be130a0 MS |
1017 | BUG_ON(!gmap_is_shadow(sg)); |
1018 | slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT); | |
1019 | if (slot) { | |
1020 | rmap->next = radix_tree_deref_slot_protected(slot, | |
1021 | &sg->guest_table_lock); | |
6d75f366 | 1022 | radix_tree_replace_slot(&sg->host_to_rmap, slot, rmap); |
4be130a0 MS |
1023 | } else { |
1024 | rmap->next = NULL; | |
1025 | radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT, | |
1026 | rmap); | |
1027 | } | |
1028 | } | |
1029 | ||
1030 | /** | |
1031 | * gmap_protect_rmap - modify access rights to memory and create an rmap | |
1032 | * @sg: pointer to the shadow guest address space structure | |
1033 | * @raddr: rmap address in the shadow gmap | |
1034 | * @paddr: address in the parent guest address space | |
1035 | * @len: length of the memory area to protect | |
1036 | * @prot: indicates access rights: none, read-only or read-write | |
1037 | * | |
1038 | * Returns 0 if successfully protected and the rmap was created, -ENOMEM | |
1039 | * if out of memory and -EFAULT if paddr is invalid. | |
1040 | */ | |
1041 | static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr, | |
1042 | unsigned long paddr, unsigned long len, int prot) | |
1043 | { | |
1044 | struct gmap *parent; | |
1045 | struct gmap_rmap *rmap; | |
1046 | unsigned long vmaddr; | |
1047 | spinlock_t *ptl; | |
1048 | pte_t *ptep; | |
1049 | int rc; | |
1050 | ||
1051 | BUG_ON(!gmap_is_shadow(sg)); | |
1052 | parent = sg->parent; | |
1053 | while (len) { | |
1054 | vmaddr = __gmap_translate(parent, paddr); | |
1055 | if (IS_ERR_VALUE(vmaddr)) | |
1056 | return vmaddr; | |
1057 | rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); | |
1058 | if (!rmap) | |
1059 | return -ENOMEM; | |
1060 | rmap->raddr = raddr; | |
1061 | rc = radix_tree_preload(GFP_KERNEL); | |
b2d73b2a | 1062 | if (rc) { |
4be130a0 MS |
1063 | kfree(rmap); |
1064 | return rc; | |
1065 | } | |
1066 | rc = -EAGAIN; | |
1067 | ptep = gmap_pte_op_walk(parent, paddr, &ptl); | |
1068 | if (ptep) { | |
1069 | spin_lock(&sg->guest_table_lock); | |
1070 | rc = ptep_force_prot(parent->mm, paddr, ptep, prot, | |
1071 | PGSTE_VSIE_BIT); | |
1072 | if (!rc) | |
1073 | gmap_insert_rmap(sg, vmaddr, rmap); | |
1074 | spin_unlock(&sg->guest_table_lock); | |
1075 | gmap_pte_op_end(ptl); | |
1076 | } | |
1077 | radix_tree_preload_end(); | |
1078 | if (rc) { | |
1079 | kfree(rmap); | |
01f71917 | 1080 | rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); |
b2d73b2a | 1081 | if (rc) |
4be130a0 | 1082 | return rc; |
1e133ab2 | 1083 | continue; |
1e133ab2 | 1084 | } |
4be130a0 | 1085 | paddr += PAGE_SIZE; |
b2d73b2a | 1086 | len -= PAGE_SIZE; |
1e133ab2 | 1087 | } |
4be130a0 MS |
1088 | return 0; |
1089 | } | |
1090 | ||
1091 | #define _SHADOW_RMAP_MASK 0x7 | |
1092 | #define _SHADOW_RMAP_REGION1 0x5 | |
1093 | #define _SHADOW_RMAP_REGION2 0x4 | |
1094 | #define _SHADOW_RMAP_REGION3 0x3 | |
1095 | #define _SHADOW_RMAP_SEGMENT 0x2 | |
1096 | #define _SHADOW_RMAP_PGTABLE 0x1 | |
1097 | ||
1098 | /** | |
1099 | * gmap_idte_one - invalidate a single region or segment table entry | |
1100 | * @asce: region or segment table *origin* + table-type bits | |
1101 | * @vaddr: virtual address to identify the table entry to flush | |
1102 | * | |
1103 | * The invalid bit of a single region or segment table entry is set | |
1104 | * and the associated TLB entries depending on the entry are flushed. | |
1105 | * The table-type of the @asce identifies the portion of the @vaddr | |
1106 | * that is used as the invalidation index. | |
1107 | */ | |
1108 | static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr) | |
1109 | { | |
1110 | asm volatile( | |
1111 | " .insn rrf,0xb98e0000,%0,%1,0,0" | |
1112 | : : "a" (asce), "a" (vaddr) : "cc", "memory"); | |
1113 | } | |
1114 | ||
1115 | /** | |
1116 | * gmap_unshadow_page - remove a page from a shadow page table | |
1117 | * @sg: pointer to the shadow guest address space structure | |
1118 | * @raddr: rmap address in the shadow guest address space | |
1119 | * | |
1120 | * Called with the sg->guest_table_lock | |
1121 | */ | |
1122 | static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr) | |
1123 | { | |
1124 | unsigned long *table; | |
1125 | ||
1126 | BUG_ON(!gmap_is_shadow(sg)); | |
1127 | table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */ | |
1128 | if (!table || *table & _PAGE_INVALID) | |
1129 | return; | |
f1c1174f | 1130 | gmap_call_notifier(sg, raddr, raddr + _PAGE_SIZE - 1); |
4be130a0 MS |
1131 | ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table); |
1132 | } | |
1133 | ||
1134 | /** | |
1135 | * __gmap_unshadow_pgt - remove all entries from a shadow page table | |
1136 | * @sg: pointer to the shadow guest address space structure | |
1137 | * @raddr: rmap address in the shadow guest address space | |
1138 | * @pgt: pointer to the start of a shadow page table | |
1139 | * | |
1140 | * Called with the sg->guest_table_lock | |
1141 | */ | |
1142 | static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr, | |
1143 | unsigned long *pgt) | |
1144 | { | |
1145 | int i; | |
1146 | ||
1147 | BUG_ON(!gmap_is_shadow(sg)); | |
f1c1174f | 1148 | for (i = 0; i < _PAGE_ENTRIES; i++, raddr += _PAGE_SIZE) |
4be130a0 MS |
1149 | pgt[i] = _PAGE_INVALID; |
1150 | } | |
1151 | ||
1152 | /** | |
1153 | * gmap_unshadow_pgt - remove a shadow page table from a segment entry | |
1154 | * @sg: pointer to the shadow guest address space structure | |
1155 | * @raddr: address in the shadow guest address space | |
1156 | * | |
1157 | * Called with the sg->guest_table_lock | |
1158 | */ | |
1159 | static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr) | |
1160 | { | |
1161 | unsigned long sto, *ste, *pgt; | |
1162 | struct page *page; | |
1163 | ||
1164 | BUG_ON(!gmap_is_shadow(sg)); | |
1165 | ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */ | |
998f637c | 1166 | if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN)) |
4be130a0 | 1167 | return; |
f1c1174f HC |
1168 | gmap_call_notifier(sg, raddr, raddr + _SEGMENT_SIZE - 1); |
1169 | sto = (unsigned long) (ste - ((raddr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT)); | |
4be130a0 MS |
1170 | gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr); |
1171 | pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN); | |
1172 | *ste = _SEGMENT_ENTRY_EMPTY; | |
1173 | __gmap_unshadow_pgt(sg, raddr, pgt); | |
1174 | /* Free page table */ | |
1175 | page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); | |
1176 | list_del(&page->lru); | |
1177 | page_table_free_pgste(page); | |
1178 | } | |
1179 | ||
1180 | /** | |
1181 | * __gmap_unshadow_sgt - remove all entries from a shadow segment table | |
1182 | * @sg: pointer to the shadow guest address space structure | |
1183 | * @raddr: rmap address in the shadow guest address space | |
1184 | * @sgt: pointer to the start of a shadow segment table | |
1185 | * | |
1186 | * Called with the sg->guest_table_lock | |
1187 | */ | |
1188 | static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr, | |
1189 | unsigned long *sgt) | |
1190 | { | |
2be1da8d | 1191 | unsigned long *pgt; |
4be130a0 MS |
1192 | struct page *page; |
1193 | int i; | |
1194 | ||
1195 | BUG_ON(!gmap_is_shadow(sg)); | |
f1c1174f | 1196 | for (i = 0; i < _CRST_ENTRIES; i++, raddr += _SEGMENT_SIZE) { |
998f637c | 1197 | if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN)) |
4be130a0 MS |
1198 | continue; |
1199 | pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN); | |
1200 | sgt[i] = _SEGMENT_ENTRY_EMPTY; | |
1201 | __gmap_unshadow_pgt(sg, raddr, pgt); | |
1202 | /* Free page table */ | |
1203 | page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); | |
1204 | list_del(&page->lru); | |
1205 | page_table_free_pgste(page); | |
1206 | } | |
1207 | } | |
1208 | ||
1209 | /** | |
1210 | * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry | |
1211 | * @sg: pointer to the shadow guest address space structure | |
1212 | * @raddr: rmap address in the shadow guest address space | |
1213 | * | |
1214 | * Called with the shadow->guest_table_lock | |
1215 | */ | |
1216 | static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr) | |
1217 | { | |
1218 | unsigned long r3o, *r3e, *sgt; | |
1219 | struct page *page; | |
1220 | ||
1221 | BUG_ON(!gmap_is_shadow(sg)); | |
1222 | r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */ | |
998f637c | 1223 | if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN)) |
4be130a0 | 1224 | return; |
f1c1174f HC |
1225 | gmap_call_notifier(sg, raddr, raddr + _REGION3_SIZE - 1); |
1226 | r3o = (unsigned long) (r3e - ((raddr & _REGION3_INDEX) >> _REGION3_SHIFT)); | |
4be130a0 MS |
1227 | gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr); |
1228 | sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN); | |
1229 | *r3e = _REGION3_ENTRY_EMPTY; | |
1230 | __gmap_unshadow_sgt(sg, raddr, sgt); | |
1231 | /* Free segment table */ | |
1232 | page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); | |
1233 | list_del(&page->lru); | |
f1c1174f | 1234 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1235 | } |
1236 | ||
1237 | /** | |
1238 | * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table | |
1239 | * @sg: pointer to the shadow guest address space structure | |
1240 | * @raddr: address in the shadow guest address space | |
1241 | * @r3t: pointer to the start of a shadow region-3 table | |
1242 | * | |
1243 | * Called with the sg->guest_table_lock | |
1244 | */ | |
1245 | static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr, | |
1246 | unsigned long *r3t) | |
1247 | { | |
2be1da8d | 1248 | unsigned long *sgt; |
4be130a0 MS |
1249 | struct page *page; |
1250 | int i; | |
1251 | ||
1252 | BUG_ON(!gmap_is_shadow(sg)); | |
f1c1174f | 1253 | for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION3_SIZE) { |
998f637c | 1254 | if (!(r3t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1255 | continue; |
1256 | sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN); | |
1257 | r3t[i] = _REGION3_ENTRY_EMPTY; | |
1258 | __gmap_unshadow_sgt(sg, raddr, sgt); | |
1259 | /* Free segment table */ | |
1260 | page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); | |
1261 | list_del(&page->lru); | |
f1c1174f | 1262 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1263 | } |
1264 | } | |
1265 | ||
1266 | /** | |
1267 | * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry | |
1268 | * @sg: pointer to the shadow guest address space structure | |
1269 | * @raddr: rmap address in the shadow guest address space | |
1270 | * | |
1271 | * Called with the sg->guest_table_lock | |
1272 | */ | |
1273 | static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr) | |
1274 | { | |
1275 | unsigned long r2o, *r2e, *r3t; | |
1276 | struct page *page; | |
1277 | ||
1278 | BUG_ON(!gmap_is_shadow(sg)); | |
1279 | r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */ | |
998f637c | 1280 | if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN)) |
4be130a0 | 1281 | return; |
f1c1174f HC |
1282 | gmap_call_notifier(sg, raddr, raddr + _REGION2_SIZE - 1); |
1283 | r2o = (unsigned long) (r2e - ((raddr & _REGION2_INDEX) >> _REGION2_SHIFT)); | |
4be130a0 MS |
1284 | gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr); |
1285 | r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN); | |
1286 | *r2e = _REGION2_ENTRY_EMPTY; | |
1287 | __gmap_unshadow_r3t(sg, raddr, r3t); | |
1288 | /* Free region 3 table */ | |
1289 | page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); | |
1290 | list_del(&page->lru); | |
f1c1174f | 1291 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1292 | } |
1293 | ||
1294 | /** | |
1295 | * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table | |
1296 | * @sg: pointer to the shadow guest address space structure | |
1297 | * @raddr: rmap address in the shadow guest address space | |
1298 | * @r2t: pointer to the start of a shadow region-2 table | |
1299 | * | |
1300 | * Called with the sg->guest_table_lock | |
1301 | */ | |
1302 | static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr, | |
1303 | unsigned long *r2t) | |
1304 | { | |
2be1da8d | 1305 | unsigned long *r3t; |
4be130a0 MS |
1306 | struct page *page; |
1307 | int i; | |
1308 | ||
1309 | BUG_ON(!gmap_is_shadow(sg)); | |
f1c1174f | 1310 | for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION2_SIZE) { |
998f637c | 1311 | if (!(r2t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1312 | continue; |
1313 | r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN); | |
1314 | r2t[i] = _REGION2_ENTRY_EMPTY; | |
1315 | __gmap_unshadow_r3t(sg, raddr, r3t); | |
1316 | /* Free region 3 table */ | |
1317 | page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); | |
1318 | list_del(&page->lru); | |
f1c1174f | 1319 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1320 | } |
1321 | } | |
1322 | ||
1323 | /** | |
1324 | * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry | |
1325 | * @sg: pointer to the shadow guest address space structure | |
1326 | * @raddr: rmap address in the shadow guest address space | |
1327 | * | |
1328 | * Called with the sg->guest_table_lock | |
1329 | */ | |
1330 | static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr) | |
1331 | { | |
1332 | unsigned long r1o, *r1e, *r2t; | |
1333 | struct page *page; | |
1334 | ||
1335 | BUG_ON(!gmap_is_shadow(sg)); | |
1336 | r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */ | |
998f637c | 1337 | if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN)) |
4be130a0 | 1338 | return; |
f1c1174f HC |
1339 | gmap_call_notifier(sg, raddr, raddr + _REGION1_SIZE - 1); |
1340 | r1o = (unsigned long) (r1e - ((raddr & _REGION1_INDEX) >> _REGION1_SHIFT)); | |
4be130a0 MS |
1341 | gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr); |
1342 | r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN); | |
1343 | *r1e = _REGION1_ENTRY_EMPTY; | |
1344 | __gmap_unshadow_r2t(sg, raddr, r2t); | |
1345 | /* Free region 2 table */ | |
1346 | page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); | |
1347 | list_del(&page->lru); | |
f1c1174f | 1348 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1349 | } |
1350 | ||
1351 | /** | |
1352 | * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table | |
1353 | * @sg: pointer to the shadow guest address space structure | |
1354 | * @raddr: rmap address in the shadow guest address space | |
1355 | * @r1t: pointer to the start of a shadow region-1 table | |
1356 | * | |
1357 | * Called with the shadow->guest_table_lock | |
1358 | */ | |
1359 | static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr, | |
1360 | unsigned long *r1t) | |
1361 | { | |
1362 | unsigned long asce, *r2t; | |
1363 | struct page *page; | |
1364 | int i; | |
1365 | ||
1366 | BUG_ON(!gmap_is_shadow(sg)); | |
1367 | asce = (unsigned long) r1t | _ASCE_TYPE_REGION1; | |
f1c1174f | 1368 | for (i = 0; i < _CRST_ENTRIES; i++, raddr += _REGION1_SIZE) { |
998f637c | 1369 | if (!(r1t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1370 | continue; |
1371 | r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN); | |
1372 | __gmap_unshadow_r2t(sg, raddr, r2t); | |
1373 | /* Clear entry and flush translation r1t -> r2t */ | |
1374 | gmap_idte_one(asce, raddr); | |
1375 | r1t[i] = _REGION1_ENTRY_EMPTY; | |
1376 | /* Free region 2 table */ | |
1377 | page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); | |
1378 | list_del(&page->lru); | |
f1c1174f | 1379 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1380 | } |
1381 | } | |
1382 | ||
1383 | /** | |
1384 | * gmap_unshadow - remove a shadow page table completely | |
1385 | * @sg: pointer to the shadow guest address space structure | |
1386 | * | |
1387 | * Called with sg->guest_table_lock | |
1388 | */ | |
1389 | static void gmap_unshadow(struct gmap *sg) | |
1390 | { | |
1391 | unsigned long *table; | |
1392 | ||
1393 | BUG_ON(!gmap_is_shadow(sg)); | |
1394 | if (sg->removed) | |
1395 | return; | |
1396 | sg->removed = 1; | |
1397 | gmap_call_notifier(sg, 0, -1UL); | |
eea3678d | 1398 | gmap_flush_tlb(sg); |
4be130a0 MS |
1399 | table = (unsigned long *)(sg->asce & _ASCE_ORIGIN); |
1400 | switch (sg->asce & _ASCE_TYPE_MASK) { | |
1401 | case _ASCE_TYPE_REGION1: | |
1402 | __gmap_unshadow_r1t(sg, 0, table); | |
1403 | break; | |
1404 | case _ASCE_TYPE_REGION2: | |
1405 | __gmap_unshadow_r2t(sg, 0, table); | |
1406 | break; | |
1407 | case _ASCE_TYPE_REGION3: | |
1408 | __gmap_unshadow_r3t(sg, 0, table); | |
1409 | break; | |
1410 | case _ASCE_TYPE_SEGMENT: | |
1411 | __gmap_unshadow_sgt(sg, 0, table); | |
1412 | break; | |
1413 | } | |
1414 | } | |
1415 | ||
1416 | /** | |
1417 | * gmap_find_shadow - find a specific asce in the list of shadow tables | |
1418 | * @parent: pointer to the parent gmap | |
1419 | * @asce: ASCE for which the shadow table is created | |
5b062bd4 | 1420 | * @edat_level: edat level to be used for the shadow translation |
4be130a0 MS |
1421 | * |
1422 | * Returns the pointer to a gmap if a shadow table with the given asce is | |
0f7f8489 DH |
1423 | * already available, ERR_PTR(-EAGAIN) if another one is just being created, |
1424 | * otherwise NULL | |
4be130a0 | 1425 | */ |
5b062bd4 DH |
1426 | static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce, |
1427 | int edat_level) | |
4be130a0 MS |
1428 | { |
1429 | struct gmap *sg; | |
1430 | ||
1431 | list_for_each_entry(sg, &parent->children, list) { | |
5b062bd4 DH |
1432 | if (sg->orig_asce != asce || sg->edat_level != edat_level || |
1433 | sg->removed) | |
4be130a0 | 1434 | continue; |
0f7f8489 DH |
1435 | if (!sg->initialized) |
1436 | return ERR_PTR(-EAGAIN); | |
4be130a0 MS |
1437 | atomic_inc(&sg->ref_count); |
1438 | return sg; | |
1439 | } | |
1440 | return NULL; | |
1441 | } | |
1442 | ||
5b6c963b DH |
1443 | /** |
1444 | * gmap_shadow_valid - check if a shadow guest address space matches the | |
1445 | * given properties and is still valid | |
1446 | * @sg: pointer to the shadow guest address space structure | |
1447 | * @asce: ASCE for which the shadow table is requested | |
1448 | * @edat_level: edat level to be used for the shadow translation | |
1449 | * | |
1450 | * Returns 1 if the gmap shadow is still valid and matches the given | |
1451 | * properties, the caller can continue using it. Returns 0 otherwise, the | |
1452 | * caller has to request a new shadow gmap in this case. | |
1453 | * | |
1454 | */ | |
1455 | int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level) | |
1456 | { | |
1457 | if (sg->removed) | |
1458 | return 0; | |
1459 | return sg->orig_asce == asce && sg->edat_level == edat_level; | |
1460 | } | |
1461 | EXPORT_SYMBOL_GPL(gmap_shadow_valid); | |
1462 | ||
4be130a0 MS |
1463 | /** |
1464 | * gmap_shadow - create/find a shadow guest address space | |
1465 | * @parent: pointer to the parent gmap | |
1466 | * @asce: ASCE for which the shadow table is created | |
5b062bd4 | 1467 | * @edat_level: edat level to be used for the shadow translation |
4be130a0 MS |
1468 | * |
1469 | * The pages of the top level page table referred by the asce parameter | |
1470 | * will be set to read-only and marked in the PGSTEs of the kvm process. | |
1471 | * The shadow table will be removed automatically on any change to the | |
1472 | * PTE mapping for the source table. | |
1473 | * | |
0f7f8489 DH |
1474 | * Returns a guest address space structure, ERR_PTR(-ENOMEM) if out of memory, |
1475 | * ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the | |
1476 | * parent gmap table could not be protected. | |
4be130a0 | 1477 | */ |
5b062bd4 DH |
1478 | struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, |
1479 | int edat_level) | |
4be130a0 MS |
1480 | { |
1481 | struct gmap *sg, *new; | |
1482 | unsigned long limit; | |
1483 | int rc; | |
1484 | ||
1485 | BUG_ON(gmap_is_shadow(parent)); | |
1486 | spin_lock(&parent->shadow_lock); | |
5b062bd4 | 1487 | sg = gmap_find_shadow(parent, asce, edat_level); |
4be130a0 MS |
1488 | spin_unlock(&parent->shadow_lock); |
1489 | if (sg) | |
1490 | return sg; | |
1491 | /* Create a new shadow gmap */ | |
1492 | limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11)); | |
3218f709 DH |
1493 | if (asce & _ASCE_REAL_SPACE) |
1494 | limit = -1UL; | |
4be130a0 MS |
1495 | new = gmap_alloc(limit); |
1496 | if (!new) | |
0f7f8489 | 1497 | return ERR_PTR(-ENOMEM); |
4be130a0 MS |
1498 | new->mm = parent->mm; |
1499 | new->parent = gmap_get(parent); | |
1500 | new->orig_asce = asce; | |
5b062bd4 | 1501 | new->edat_level = edat_level; |
0f7f8489 DH |
1502 | new->initialized = false; |
1503 | spin_lock(&parent->shadow_lock); | |
1504 | /* Recheck if another CPU created the same shadow */ | |
5b062bd4 | 1505 | sg = gmap_find_shadow(parent, asce, edat_level); |
0f7f8489 DH |
1506 | if (sg) { |
1507 | spin_unlock(&parent->shadow_lock); | |
1508 | gmap_free(new); | |
1509 | return sg; | |
1510 | } | |
717c0555 DH |
1511 | if (asce & _ASCE_REAL_SPACE) { |
1512 | /* only allow one real-space gmap shadow */ | |
1513 | list_for_each_entry(sg, &parent->children, list) { | |
1514 | if (sg->orig_asce & _ASCE_REAL_SPACE) { | |
1515 | spin_lock(&sg->guest_table_lock); | |
1516 | gmap_unshadow(sg); | |
1517 | spin_unlock(&sg->guest_table_lock); | |
1518 | list_del(&sg->list); | |
1519 | gmap_put(sg); | |
1520 | break; | |
1521 | } | |
1522 | } | |
1523 | } | |
0f7f8489 DH |
1524 | atomic_set(&new->ref_count, 2); |
1525 | list_add(&new->list, &parent->children); | |
3218f709 DH |
1526 | if (asce & _ASCE_REAL_SPACE) { |
1527 | /* nothing to protect, return right away */ | |
1528 | new->initialized = true; | |
1529 | spin_unlock(&parent->shadow_lock); | |
1530 | return new; | |
1531 | } | |
0f7f8489 DH |
1532 | spin_unlock(&parent->shadow_lock); |
1533 | /* protect after insertion, so it will get properly invalidated */ | |
4be130a0 MS |
1534 | down_read(&parent->mm->mmap_sem); |
1535 | rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN, | |
f1c1174f | 1536 | ((asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE, |
4be130a0 MS |
1537 | PROT_READ, PGSTE_VSIE_BIT); |
1538 | up_read(&parent->mm->mmap_sem); | |
0f7f8489 DH |
1539 | spin_lock(&parent->shadow_lock); |
1540 | new->initialized = true; | |
4be130a0 | 1541 | if (rc) { |
0f7f8489 | 1542 | list_del(&new->list); |
4be130a0 | 1543 | gmap_free(new); |
0f7f8489 DH |
1544 | new = ERR_PTR(rc); |
1545 | } | |
1546 | spin_unlock(&parent->shadow_lock); | |
1547 | return new; | |
4be130a0 MS |
1548 | } |
1549 | EXPORT_SYMBOL_GPL(gmap_shadow); | |
1550 | ||
1551 | /** | |
1552 | * gmap_shadow_r2t - create an empty shadow region 2 table | |
1553 | * @sg: pointer to the shadow guest address space structure | |
1554 | * @saddr: faulting address in the shadow gmap | |
1555 | * @r2t: parent gmap address of the region 2 table to get shadowed | |
3218f709 | 1556 | * @fake: r2t references contiguous guest memory block, not a r2t |
4be130a0 MS |
1557 | * |
1558 | * The r2t parameter specifies the address of the source table. The | |
1559 | * four pages of the source table are made read-only in the parent gmap | |
1560 | * address space. A write to the source table area @r2t will automatically | |
1561 | * remove the shadow r2 table and all of its decendents. | |
1562 | * | |
1563 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1564 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1565 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1566 | * | |
1567 | * Called with sg->mm->mmap_sem in read. | |
1568 | */ | |
3218f709 DH |
1569 | int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, |
1570 | int fake) | |
4be130a0 MS |
1571 | { |
1572 | unsigned long raddr, origin, offset, len; | |
1573 | unsigned long *s_r2t, *table; | |
1574 | struct page *page; | |
1575 | int rc; | |
1576 | ||
1577 | BUG_ON(!gmap_is_shadow(sg)); | |
1578 | /* Allocate a shadow region second table */ | |
f1c1174f | 1579 | page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); |
4be130a0 MS |
1580 | if (!page) |
1581 | return -ENOMEM; | |
1582 | page->index = r2t & _REGION_ENTRY_ORIGIN; | |
3218f709 DH |
1583 | if (fake) |
1584 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1585 | s_r2t = (unsigned long *) page_to_phys(page); |
1586 | /* Install shadow region second table */ | |
1587 | spin_lock(&sg->guest_table_lock); | |
1588 | table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */ | |
1589 | if (!table) { | |
1590 | rc = -EAGAIN; /* Race with unshadow */ | |
1591 | goto out_free; | |
1592 | } | |
1593 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1594 | rc = 0; /* Already established */ | |
1595 | goto out_free; | |
998f637c DH |
1596 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1597 | rc = -EAGAIN; /* Race with shadow */ | |
1598 | goto out_free; | |
4be130a0 MS |
1599 | } |
1600 | crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY); | |
998f637c DH |
1601 | /* mark as invalid as long as the parent table is not protected */ |
1602 | *table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH | | |
1603 | _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1604 | if (sg->edat_level >= 1) |
1605 | *table |= (r2t & _REGION_ENTRY_PROTECT); | |
4be130a0 | 1606 | list_add(&page->lru, &sg->crst_list); |
3218f709 DH |
1607 | if (fake) { |
1608 | /* nothing to protect for fake tables */ | |
1609 | *table &= ~_REGION_ENTRY_INVALID; | |
1610 | spin_unlock(&sg->guest_table_lock); | |
1611 | return 0; | |
1612 | } | |
4be130a0 MS |
1613 | spin_unlock(&sg->guest_table_lock); |
1614 | /* Make r2t read-only in parent gmap page table */ | |
f1c1174f | 1615 | raddr = (saddr & _REGION1_MASK) | _SHADOW_RMAP_REGION1; |
4be130a0 | 1616 | origin = r2t & _REGION_ENTRY_ORIGIN; |
f1c1174f HC |
1617 | offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; |
1618 | len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; | |
4be130a0 | 1619 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); |
998f637c DH |
1620 | spin_lock(&sg->guest_table_lock); |
1621 | if (!rc) { | |
1622 | table = gmap_table_walk(sg, saddr, 4); | |
1623 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1624 | (unsigned long) s_r2t) | |
1625 | rc = -EAGAIN; /* Race with unshadow */ | |
1626 | else | |
1627 | *table &= ~_REGION_ENTRY_INVALID; | |
1628 | } else { | |
4be130a0 | 1629 | gmap_unshadow_r2t(sg, raddr); |
4be130a0 | 1630 | } |
998f637c | 1631 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1632 | return rc; |
1633 | out_free: | |
1634 | spin_unlock(&sg->guest_table_lock); | |
f1c1174f | 1635 | __free_pages(page, CRST_ALLOC_ORDER); |
1e133ab2 MS |
1636 | return rc; |
1637 | } | |
4be130a0 MS |
1638 | EXPORT_SYMBOL_GPL(gmap_shadow_r2t); |
1639 | ||
1640 | /** | |
1641 | * gmap_shadow_r3t - create a shadow region 3 table | |
1642 | * @sg: pointer to the shadow guest address space structure | |
1643 | * @saddr: faulting address in the shadow gmap | |
1644 | * @r3t: parent gmap address of the region 3 table to get shadowed | |
3218f709 | 1645 | * @fake: r3t references contiguous guest memory block, not a r3t |
4be130a0 MS |
1646 | * |
1647 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1648 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1649 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1650 | * | |
1651 | * Called with sg->mm->mmap_sem in read. | |
1652 | */ | |
3218f709 DH |
1653 | int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, |
1654 | int fake) | |
4be130a0 MS |
1655 | { |
1656 | unsigned long raddr, origin, offset, len; | |
1657 | unsigned long *s_r3t, *table; | |
1658 | struct page *page; | |
1659 | int rc; | |
1660 | ||
1661 | BUG_ON(!gmap_is_shadow(sg)); | |
1662 | /* Allocate a shadow region second table */ | |
f1c1174f | 1663 | page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); |
4be130a0 MS |
1664 | if (!page) |
1665 | return -ENOMEM; | |
1666 | page->index = r3t & _REGION_ENTRY_ORIGIN; | |
3218f709 DH |
1667 | if (fake) |
1668 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1669 | s_r3t = (unsigned long *) page_to_phys(page); |
1670 | /* Install shadow region second table */ | |
1671 | spin_lock(&sg->guest_table_lock); | |
1672 | table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */ | |
1673 | if (!table) { | |
1674 | rc = -EAGAIN; /* Race with unshadow */ | |
1675 | goto out_free; | |
1676 | } | |
1677 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1678 | rc = 0; /* Already established */ | |
1679 | goto out_free; | |
998f637c DH |
1680 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1681 | rc = -EAGAIN; /* Race with shadow */ | |
4be130a0 MS |
1682 | } |
1683 | crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY); | |
998f637c DH |
1684 | /* mark as invalid as long as the parent table is not protected */ |
1685 | *table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH | | |
1686 | _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1687 | if (sg->edat_level >= 1) |
1688 | *table |= (r3t & _REGION_ENTRY_PROTECT); | |
4be130a0 | 1689 | list_add(&page->lru, &sg->crst_list); |
3218f709 DH |
1690 | if (fake) { |
1691 | /* nothing to protect for fake tables */ | |
1692 | *table &= ~_REGION_ENTRY_INVALID; | |
1693 | spin_unlock(&sg->guest_table_lock); | |
1694 | return 0; | |
1695 | } | |
4be130a0 MS |
1696 | spin_unlock(&sg->guest_table_lock); |
1697 | /* Make r3t read-only in parent gmap page table */ | |
f1c1174f | 1698 | raddr = (saddr & _REGION2_MASK) | _SHADOW_RMAP_REGION2; |
4be130a0 | 1699 | origin = r3t & _REGION_ENTRY_ORIGIN; |
f1c1174f HC |
1700 | offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; |
1701 | len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; | |
4be130a0 | 1702 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); |
998f637c DH |
1703 | spin_lock(&sg->guest_table_lock); |
1704 | if (!rc) { | |
1705 | table = gmap_table_walk(sg, saddr, 3); | |
1706 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1707 | (unsigned long) s_r3t) | |
1708 | rc = -EAGAIN; /* Race with unshadow */ | |
1709 | else | |
1710 | *table &= ~_REGION_ENTRY_INVALID; | |
1711 | } else { | |
4be130a0 | 1712 | gmap_unshadow_r3t(sg, raddr); |
4be130a0 | 1713 | } |
998f637c | 1714 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1715 | return rc; |
1716 | out_free: | |
1717 | spin_unlock(&sg->guest_table_lock); | |
f1c1174f | 1718 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1719 | return rc; |
1720 | } | |
1721 | EXPORT_SYMBOL_GPL(gmap_shadow_r3t); | |
1722 | ||
1723 | /** | |
1724 | * gmap_shadow_sgt - create a shadow segment table | |
1725 | * @sg: pointer to the shadow guest address space structure | |
1726 | * @saddr: faulting address in the shadow gmap | |
1727 | * @sgt: parent gmap address of the segment table to get shadowed | |
18b89809 | 1728 | * @fake: sgt references contiguous guest memory block, not a sgt |
4be130a0 MS |
1729 | * |
1730 | * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1731 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1732 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1733 | * | |
1734 | * Called with sg->mm->mmap_sem in read. | |
1735 | */ | |
18b89809 DH |
1736 | int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, |
1737 | int fake) | |
4be130a0 MS |
1738 | { |
1739 | unsigned long raddr, origin, offset, len; | |
1740 | unsigned long *s_sgt, *table; | |
1741 | struct page *page; | |
1742 | int rc; | |
1743 | ||
18b89809 | 1744 | BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE)); |
4be130a0 | 1745 | /* Allocate a shadow segment table */ |
f1c1174f | 1746 | page = alloc_pages(GFP_KERNEL, CRST_ALLOC_ORDER); |
4be130a0 MS |
1747 | if (!page) |
1748 | return -ENOMEM; | |
1749 | page->index = sgt & _REGION_ENTRY_ORIGIN; | |
18b89809 DH |
1750 | if (fake) |
1751 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1752 | s_sgt = (unsigned long *) page_to_phys(page); |
1753 | /* Install shadow region second table */ | |
1754 | spin_lock(&sg->guest_table_lock); | |
1755 | table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */ | |
1756 | if (!table) { | |
1757 | rc = -EAGAIN; /* Race with unshadow */ | |
1758 | goto out_free; | |
1759 | } | |
1760 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1761 | rc = 0; /* Already established */ | |
1762 | goto out_free; | |
998f637c DH |
1763 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1764 | rc = -EAGAIN; /* Race with shadow */ | |
1765 | goto out_free; | |
4be130a0 MS |
1766 | } |
1767 | crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY); | |
998f637c DH |
1768 | /* mark as invalid as long as the parent table is not protected */ |
1769 | *table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH | | |
1770 | _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1771 | if (sg->edat_level >= 1) |
1772 | *table |= sgt & _REGION_ENTRY_PROTECT; | |
4be130a0 | 1773 | list_add(&page->lru, &sg->crst_list); |
18b89809 DH |
1774 | if (fake) { |
1775 | /* nothing to protect for fake tables */ | |
1776 | *table &= ~_REGION_ENTRY_INVALID; | |
1777 | spin_unlock(&sg->guest_table_lock); | |
1778 | return 0; | |
1779 | } | |
4be130a0 MS |
1780 | spin_unlock(&sg->guest_table_lock); |
1781 | /* Make sgt read-only in parent gmap page table */ | |
f1c1174f | 1782 | raddr = (saddr & _REGION3_MASK) | _SHADOW_RMAP_REGION3; |
4be130a0 | 1783 | origin = sgt & _REGION_ENTRY_ORIGIN; |
f1c1174f HC |
1784 | offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * PAGE_SIZE; |
1785 | len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * PAGE_SIZE - offset; | |
4be130a0 | 1786 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); |
998f637c DH |
1787 | spin_lock(&sg->guest_table_lock); |
1788 | if (!rc) { | |
1789 | table = gmap_table_walk(sg, saddr, 2); | |
1790 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1791 | (unsigned long) s_sgt) | |
1792 | rc = -EAGAIN; /* Race with unshadow */ | |
1793 | else | |
1794 | *table &= ~_REGION_ENTRY_INVALID; | |
1795 | } else { | |
4be130a0 | 1796 | gmap_unshadow_sgt(sg, raddr); |
4be130a0 | 1797 | } |
998f637c | 1798 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1799 | return rc; |
1800 | out_free: | |
1801 | spin_unlock(&sg->guest_table_lock); | |
f1c1174f | 1802 | __free_pages(page, CRST_ALLOC_ORDER); |
4be130a0 MS |
1803 | return rc; |
1804 | } | |
1805 | EXPORT_SYMBOL_GPL(gmap_shadow_sgt); | |
1806 | ||
1807 | /** | |
1808 | * gmap_shadow_lookup_pgtable - find a shadow page table | |
1809 | * @sg: pointer to the shadow guest address space structure | |
1810 | * @saddr: the address in the shadow aguest address space | |
1811 | * @pgt: parent gmap address of the page table to get shadowed | |
1812 | * @dat_protection: if the pgtable is marked as protected by dat | |
fd8d4e3a | 1813 | * @fake: pgt references contiguous guest memory block, not a pgtable |
4be130a0 MS |
1814 | * |
1815 | * Returns 0 if the shadow page table was found and -EAGAIN if the page | |
1816 | * table was not found. | |
1817 | * | |
1818 | * Called with sg->mm->mmap_sem in read. | |
1819 | */ | |
1820 | int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, | |
fd8d4e3a DH |
1821 | unsigned long *pgt, int *dat_protection, |
1822 | int *fake) | |
4be130a0 MS |
1823 | { |
1824 | unsigned long *table; | |
1825 | struct page *page; | |
1826 | int rc; | |
1827 | ||
1828 | BUG_ON(!gmap_is_shadow(sg)); | |
1829 | spin_lock(&sg->guest_table_lock); | |
1830 | table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ | |
1831 | if (table && !(*table & _SEGMENT_ENTRY_INVALID)) { | |
1832 | /* Shadow page tables are full pages (pte+pgste) */ | |
1833 | page = pfn_to_page(*table >> PAGE_SHIFT); | |
fd8d4e3a | 1834 | *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE; |
4be130a0 | 1835 | *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT); |
fd8d4e3a | 1836 | *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE); |
4be130a0 MS |
1837 | rc = 0; |
1838 | } else { | |
1839 | rc = -EAGAIN; | |
1840 | } | |
1841 | spin_unlock(&sg->guest_table_lock); | |
1842 | return rc; | |
1843 | ||
1844 | } | |
1845 | EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup); | |
1846 | ||
1847 | /** | |
1848 | * gmap_shadow_pgt - instantiate a shadow page table | |
1849 | * @sg: pointer to the shadow guest address space structure | |
1850 | * @saddr: faulting address in the shadow gmap | |
1851 | * @pgt: parent gmap address of the page table to get shadowed | |
fd8d4e3a | 1852 | * @fake: pgt references contiguous guest memory block, not a pgtable |
4be130a0 MS |
1853 | * |
1854 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1855 | * shadow table structure is incomplete, -ENOMEM if out of memory, | |
1856 | * -EFAULT if an address in the parent gmap could not be resolved and | |
1857 | * | |
1858 | * Called with gmap->mm->mmap_sem in read | |
1859 | */ | |
fd8d4e3a DH |
1860 | int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, |
1861 | int fake) | |
4be130a0 MS |
1862 | { |
1863 | unsigned long raddr, origin; | |
1864 | unsigned long *s_pgt, *table; | |
1865 | struct page *page; | |
1866 | int rc; | |
1867 | ||
fd8d4e3a | 1868 | BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE)); |
4be130a0 MS |
1869 | /* Allocate a shadow page table */ |
1870 | page = page_table_alloc_pgste(sg->mm); | |
1871 | if (!page) | |
1872 | return -ENOMEM; | |
1873 | page->index = pgt & _SEGMENT_ENTRY_ORIGIN; | |
fd8d4e3a DH |
1874 | if (fake) |
1875 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1876 | s_pgt = (unsigned long *) page_to_phys(page); |
1877 | /* Install shadow page table */ | |
1878 | spin_lock(&sg->guest_table_lock); | |
1879 | table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ | |
1880 | if (!table) { | |
1881 | rc = -EAGAIN; /* Race with unshadow */ | |
1882 | goto out_free; | |
1883 | } | |
1884 | if (!(*table & _SEGMENT_ENTRY_INVALID)) { | |
1885 | rc = 0; /* Already established */ | |
1886 | goto out_free; | |
998f637c DH |
1887 | } else if (*table & _SEGMENT_ENTRY_ORIGIN) { |
1888 | rc = -EAGAIN; /* Race with shadow */ | |
1889 | goto out_free; | |
4be130a0 | 1890 | } |
998f637c | 1891 | /* mark as invalid as long as the parent table is not protected */ |
4be130a0 | 1892 | *table = (unsigned long) s_pgt | _SEGMENT_ENTRY | |
998f637c | 1893 | (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID; |
4be130a0 | 1894 | list_add(&page->lru, &sg->pt_list); |
fd8d4e3a DH |
1895 | if (fake) { |
1896 | /* nothing to protect for fake tables */ | |
1897 | *table &= ~_SEGMENT_ENTRY_INVALID; | |
1898 | spin_unlock(&sg->guest_table_lock); | |
1899 | return 0; | |
1900 | } | |
4be130a0 MS |
1901 | spin_unlock(&sg->guest_table_lock); |
1902 | /* Make pgt read-only in parent gmap page table (not the pgste) */ | |
f1c1174f | 1903 | raddr = (saddr & _SEGMENT_MASK) | _SHADOW_RMAP_SEGMENT; |
4be130a0 MS |
1904 | origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK; |
1905 | rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ); | |
998f637c DH |
1906 | spin_lock(&sg->guest_table_lock); |
1907 | if (!rc) { | |
1908 | table = gmap_table_walk(sg, saddr, 1); | |
1909 | if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) != | |
1910 | (unsigned long) s_pgt) | |
1911 | rc = -EAGAIN; /* Race with unshadow */ | |
1912 | else | |
1913 | *table &= ~_SEGMENT_ENTRY_INVALID; | |
1914 | } else { | |
4be130a0 | 1915 | gmap_unshadow_pgt(sg, raddr); |
4be130a0 | 1916 | } |
998f637c | 1917 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1918 | return rc; |
1919 | out_free: | |
1920 | spin_unlock(&sg->guest_table_lock); | |
1921 | page_table_free_pgste(page); | |
1922 | return rc; | |
1923 | ||
1924 | } | |
1925 | EXPORT_SYMBOL_GPL(gmap_shadow_pgt); | |
1926 | ||
1927 | /** | |
1928 | * gmap_shadow_page - create a shadow page mapping | |
1929 | * @sg: pointer to the shadow guest address space structure | |
1930 | * @saddr: faulting address in the shadow gmap | |
a9d23e71 | 1931 | * @pte: pte in parent gmap address space to get shadowed |
4be130a0 MS |
1932 | * |
1933 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1934 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1935 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1936 | * | |
1937 | * Called with sg->mm->mmap_sem in read. | |
1938 | */ | |
a9d23e71 | 1939 | int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte) |
4be130a0 MS |
1940 | { |
1941 | struct gmap *parent; | |
1942 | struct gmap_rmap *rmap; | |
a9d23e71 | 1943 | unsigned long vmaddr, paddr; |
4be130a0 MS |
1944 | spinlock_t *ptl; |
1945 | pte_t *sptep, *tptep; | |
01f71917 | 1946 | int prot; |
4be130a0 MS |
1947 | int rc; |
1948 | ||
1949 | BUG_ON(!gmap_is_shadow(sg)); | |
1950 | parent = sg->parent; | |
01f71917 | 1951 | prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE; |
4be130a0 MS |
1952 | |
1953 | rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); | |
1954 | if (!rmap) | |
1955 | return -ENOMEM; | |
1956 | rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE; | |
1957 | ||
1958 | while (1) { | |
a9d23e71 | 1959 | paddr = pte_val(pte) & PAGE_MASK; |
4be130a0 MS |
1960 | vmaddr = __gmap_translate(parent, paddr); |
1961 | if (IS_ERR_VALUE(vmaddr)) { | |
1962 | rc = vmaddr; | |
1963 | break; | |
1964 | } | |
1965 | rc = radix_tree_preload(GFP_KERNEL); | |
1966 | if (rc) | |
1967 | break; | |
1968 | rc = -EAGAIN; | |
1969 | sptep = gmap_pte_op_walk(parent, paddr, &ptl); | |
1970 | if (sptep) { | |
1971 | spin_lock(&sg->guest_table_lock); | |
1972 | /* Get page table pointer */ | |
1973 | tptep = (pte_t *) gmap_table_walk(sg, saddr, 0); | |
1974 | if (!tptep) { | |
1975 | spin_unlock(&sg->guest_table_lock); | |
1976 | gmap_pte_op_end(ptl); | |
1977 | radix_tree_preload_end(); | |
1978 | break; | |
1979 | } | |
a9d23e71 | 1980 | rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte); |
4be130a0 MS |
1981 | if (rc > 0) { |
1982 | /* Success and a new mapping */ | |
1983 | gmap_insert_rmap(sg, vmaddr, rmap); | |
1984 | rmap = NULL; | |
1985 | rc = 0; | |
1986 | } | |
1987 | gmap_pte_op_end(ptl); | |
1988 | spin_unlock(&sg->guest_table_lock); | |
1989 | } | |
1990 | radix_tree_preload_end(); | |
1991 | if (!rc) | |
1992 | break; | |
01f71917 | 1993 | rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); |
4be130a0 MS |
1994 | if (rc) |
1995 | break; | |
1996 | } | |
1997 | kfree(rmap); | |
1998 | return rc; | |
1999 | } | |
2000 | EXPORT_SYMBOL_GPL(gmap_shadow_page); | |
2001 | ||
2002 | /** | |
2003 | * gmap_shadow_notify - handle notifications for shadow gmap | |
2004 | * | |
2005 | * Called with sg->parent->shadow_lock. | |
2006 | */ | |
2007 | static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr, | |
2fa5ed7d | 2008 | unsigned long gaddr, pte_t *pte) |
4be130a0 MS |
2009 | { |
2010 | struct gmap_rmap *rmap, *rnext, *head; | |
2fa5ed7d | 2011 | unsigned long start, end, bits, raddr; |
4be130a0 MS |
2012 | |
2013 | BUG_ON(!gmap_is_shadow(sg)); | |
4be130a0 MS |
2014 | |
2015 | spin_lock(&sg->guest_table_lock); | |
2016 | if (sg->removed) { | |
2017 | spin_unlock(&sg->guest_table_lock); | |
2018 | return; | |
2019 | } | |
2020 | /* Check for top level table */ | |
2021 | start = sg->orig_asce & _ASCE_ORIGIN; | |
f1c1174f | 2022 | end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * PAGE_SIZE; |
3218f709 DH |
2023 | if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start && |
2024 | gaddr < end) { | |
4be130a0 MS |
2025 | /* The complete shadow table has to go */ |
2026 | gmap_unshadow(sg); | |
2027 | spin_unlock(&sg->guest_table_lock); | |
2028 | list_del(&sg->list); | |
2029 | gmap_put(sg); | |
2030 | return; | |
2031 | } | |
2032 | /* Remove the page table tree from on specific entry */ | |
f1c1174f | 2033 | head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT); |
4be130a0 MS |
2034 | gmap_for_each_rmap_safe(rmap, rnext, head) { |
2035 | bits = rmap->raddr & _SHADOW_RMAP_MASK; | |
2036 | raddr = rmap->raddr ^ bits; | |
2037 | switch (bits) { | |
2038 | case _SHADOW_RMAP_REGION1: | |
2039 | gmap_unshadow_r2t(sg, raddr); | |
2040 | break; | |
2041 | case _SHADOW_RMAP_REGION2: | |
2042 | gmap_unshadow_r3t(sg, raddr); | |
2043 | break; | |
2044 | case _SHADOW_RMAP_REGION3: | |
2045 | gmap_unshadow_sgt(sg, raddr); | |
2046 | break; | |
2047 | case _SHADOW_RMAP_SEGMENT: | |
2048 | gmap_unshadow_pgt(sg, raddr); | |
2049 | break; | |
2050 | case _SHADOW_RMAP_PGTABLE: | |
2051 | gmap_unshadow_page(sg, raddr); | |
2052 | break; | |
2053 | } | |
2054 | kfree(rmap); | |
2055 | } | |
2056 | spin_unlock(&sg->guest_table_lock); | |
2057 | } | |
1e133ab2 MS |
2058 | |
2059 | /** | |
2060 | * ptep_notify - call all invalidation callbacks for a specific pte. | |
2061 | * @mm: pointer to the process mm_struct | |
2062 | * @addr: virtual address in the process address space | |
2063 | * @pte: pointer to the page table entry | |
4be130a0 | 2064 | * @bits: bits from the pgste that caused the notify call |
1e133ab2 MS |
2065 | * |
2066 | * This function is assumed to be called with the page table lock held | |
2067 | * for the pte to notify. | |
2068 | */ | |
4be130a0 MS |
2069 | void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, |
2070 | pte_t *pte, unsigned long bits) | |
1e133ab2 | 2071 | { |
2fa5ed7d | 2072 | unsigned long offset, gaddr = 0; |
1e133ab2 | 2073 | unsigned long *table; |
4be130a0 | 2074 | struct gmap *gmap, *sg, *next; |
1e133ab2 MS |
2075 | |
2076 | offset = ((unsigned long) pte) & (255 * sizeof(pte_t)); | |
f1c1174f | 2077 | offset = offset * (PAGE_SIZE / sizeof(pte_t)); |
8ecb1a59 MS |
2078 | rcu_read_lock(); |
2079 | list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { | |
2080 | spin_lock(&gmap->guest_table_lock); | |
1e133ab2 MS |
2081 | table = radix_tree_lookup(&gmap->host_to_guest, |
2082 | vmaddr >> PMD_SHIFT); | |
8ecb1a59 MS |
2083 | if (table) |
2084 | gaddr = __gmap_segment_gaddr(table) + offset; | |
2085 | spin_unlock(&gmap->guest_table_lock); | |
2fa5ed7d JF |
2086 | if (!table) |
2087 | continue; | |
2088 | ||
2089 | if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) { | |
2090 | spin_lock(&gmap->shadow_lock); | |
2091 | list_for_each_entry_safe(sg, next, | |
2092 | &gmap->children, list) | |
2093 | gmap_shadow_notify(sg, vmaddr, gaddr, pte); | |
2094 | spin_unlock(&gmap->shadow_lock); | |
2095 | } | |
2096 | if (bits & PGSTE_IN_BIT) | |
8ecb1a59 | 2097 | gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1); |
1e133ab2 | 2098 | } |
8ecb1a59 | 2099 | rcu_read_unlock(); |
1e133ab2 MS |
2100 | } |
2101 | EXPORT_SYMBOL_GPL(ptep_notify); | |
2102 | ||
2103 | static inline void thp_split_mm(struct mm_struct *mm) | |
2104 | { | |
2105 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
2106 | struct vm_area_struct *vma; | |
2107 | unsigned long addr; | |
2108 | ||
2109 | for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) { | |
2110 | for (addr = vma->vm_start; | |
2111 | addr < vma->vm_end; | |
2112 | addr += PAGE_SIZE) | |
2113 | follow_page(vma, addr, FOLL_SPLIT); | |
2114 | vma->vm_flags &= ~VM_HUGEPAGE; | |
2115 | vma->vm_flags |= VM_NOHUGEPAGE; | |
2116 | } | |
2117 | mm->def_flags |= VM_NOHUGEPAGE; | |
2118 | #endif | |
2119 | } | |
2120 | ||
fa41ba0d CB |
2121 | /* |
2122 | * Remove all empty zero pages from the mapping for lazy refaulting | |
2123 | * - This must be called after mm->context.has_pgste is set, to avoid | |
2124 | * future creation of zero pages | |
2125 | * - This must be called after THP was enabled | |
2126 | */ | |
2127 | static int __zap_zero_pages(pmd_t *pmd, unsigned long start, | |
2128 | unsigned long end, struct mm_walk *walk) | |
2129 | { | |
2130 | unsigned long addr; | |
2131 | ||
2132 | for (addr = start; addr != end; addr += PAGE_SIZE) { | |
2133 | pte_t *ptep; | |
2134 | spinlock_t *ptl; | |
2135 | ||
2136 | ptep = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); | |
2137 | if (is_zero_pfn(pte_pfn(*ptep))) | |
2138 | ptep_xchg_direct(walk->mm, addr, ptep, __pte(_PAGE_INVALID)); | |
2139 | pte_unmap_unlock(ptep, ptl); | |
2140 | } | |
2141 | return 0; | |
2142 | } | |
2143 | ||
2144 | static inline void zap_zero_pages(struct mm_struct *mm) | |
2145 | { | |
2146 | struct mm_walk walk = { .pmd_entry = __zap_zero_pages }; | |
2147 | ||
2148 | walk.mm = mm; | |
2149 | walk_page_range(0, TASK_SIZE, &walk); | |
2150 | } | |
2151 | ||
1e133ab2 MS |
2152 | /* |
2153 | * switch on pgstes for its userspace process (for kvm) | |
2154 | */ | |
2155 | int s390_enable_sie(void) | |
2156 | { | |
2157 | struct mm_struct *mm = current->mm; | |
2158 | ||
2159 | /* Do we have pgstes? if yes, we are done */ | |
2160 | if (mm_has_pgste(mm)) | |
2161 | return 0; | |
2162 | /* Fail if the page tables are 2K */ | |
2163 | if (!mm_alloc_pgste(mm)) | |
2164 | return -EINVAL; | |
2165 | down_write(&mm->mmap_sem); | |
2166 | mm->context.has_pgste = 1; | |
2167 | /* split thp mappings and disable thp for future mappings */ | |
2168 | thp_split_mm(mm); | |
fa41ba0d | 2169 | zap_zero_pages(mm); |
1e133ab2 MS |
2170 | up_write(&mm->mmap_sem); |
2171 | return 0; | |
2172 | } | |
2173 | EXPORT_SYMBOL_GPL(s390_enable_sie); | |
2174 | ||
2175 | /* | |
2176 | * Enable storage key handling from now on and initialize the storage | |
2177 | * keys with the default key. | |
2178 | */ | |
2179 | static int __s390_enable_skey(pte_t *pte, unsigned long addr, | |
2180 | unsigned long next, struct mm_walk *walk) | |
2181 | { | |
1e133ab2 MS |
2182 | /* Clear storage key */ |
2183 | ptep_zap_key(walk->mm, addr, pte); | |
2184 | return 0; | |
2185 | } | |
2186 | ||
2187 | int s390_enable_skey(void) | |
2188 | { | |
2189 | struct mm_walk walk = { .pte_entry = __s390_enable_skey }; | |
2190 | struct mm_struct *mm = current->mm; | |
2191 | struct vm_area_struct *vma; | |
2192 | int rc = 0; | |
2193 | ||
2194 | down_write(&mm->mmap_sem); | |
2195 | if (mm_use_skey(mm)) | |
2196 | goto out_up; | |
2197 | ||
2198 | mm->context.use_skey = 1; | |
2199 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
2200 | if (ksm_madvise(vma, vma->vm_start, vma->vm_end, | |
2201 | MADV_UNMERGEABLE, &vma->vm_flags)) { | |
2202 | mm->context.use_skey = 0; | |
2203 | rc = -ENOMEM; | |
2204 | goto out_up; | |
2205 | } | |
2206 | } | |
2207 | mm->def_flags &= ~VM_MERGEABLE; | |
2208 | ||
2209 | walk.mm = mm; | |
2210 | walk_page_range(0, TASK_SIZE, &walk); | |
2211 | ||
2212 | out_up: | |
2213 | up_write(&mm->mmap_sem); | |
2214 | return rc; | |
2215 | } | |
2216 | EXPORT_SYMBOL_GPL(s390_enable_skey); | |
2217 | ||
2218 | /* | |
2219 | * Reset CMMA state, make all pages stable again. | |
2220 | */ | |
2221 | static int __s390_reset_cmma(pte_t *pte, unsigned long addr, | |
2222 | unsigned long next, struct mm_walk *walk) | |
2223 | { | |
2224 | ptep_zap_unused(walk->mm, addr, pte, 1); | |
2225 | return 0; | |
2226 | } | |
2227 | ||
2228 | void s390_reset_cmma(struct mm_struct *mm) | |
2229 | { | |
2230 | struct mm_walk walk = { .pte_entry = __s390_reset_cmma }; | |
2231 | ||
2232 | down_write(&mm->mmap_sem); | |
2233 | walk.mm = mm; | |
2234 | walk_page_range(0, TASK_SIZE, &walk); | |
2235 | up_write(&mm->mmap_sem); | |
2236 | } | |
2237 | EXPORT_SYMBOL_GPL(s390_reset_cmma); |