Commit | Line | Data |
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1e133ab2 MS |
1 | /* |
2 | * KVM guest address space mapping code | |
3 | * | |
4 | * Copyright IBM Corp. 2007, 2016 | |
5 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> | |
6 | */ | |
7 | ||
8 | #include <linux/kernel.h> | |
9 | #include <linux/mm.h> | |
10 | #include <linux/swap.h> | |
11 | #include <linux/smp.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/slab.h> | |
14 | #include <linux/swapops.h> | |
15 | #include <linux/ksm.h> | |
16 | #include <linux/mman.h> | |
17 | ||
18 | #include <asm/pgtable.h> | |
19 | #include <asm/pgalloc.h> | |
20 | #include <asm/gmap.h> | |
21 | #include <asm/tlb.h> | |
22 | ||
fd8d4e3a DH |
23 | #define GMAP_SHADOW_FAKE_TABLE 1ULL |
24 | ||
1e133ab2 | 25 | /** |
6ea427bb | 26 | * gmap_alloc - allocate and initialize a guest address space |
1e133ab2 | 27 | * @mm: pointer to the parent mm_struct |
9c650d09 | 28 | * @limit: maximum address of the gmap address space |
1e133ab2 MS |
29 | * |
30 | * Returns a guest address space structure. | |
31 | */ | |
6ea427bb | 32 | static struct gmap *gmap_alloc(unsigned long limit) |
1e133ab2 MS |
33 | { |
34 | struct gmap *gmap; | |
35 | struct page *page; | |
36 | unsigned long *table; | |
37 | unsigned long etype, atype; | |
38 | ||
39 | if (limit < (1UL << 31)) { | |
40 | limit = (1UL << 31) - 1; | |
41 | atype = _ASCE_TYPE_SEGMENT; | |
42 | etype = _SEGMENT_ENTRY_EMPTY; | |
43 | } else if (limit < (1UL << 42)) { | |
44 | limit = (1UL << 42) - 1; | |
45 | atype = _ASCE_TYPE_REGION3; | |
46 | etype = _REGION3_ENTRY_EMPTY; | |
47 | } else if (limit < (1UL << 53)) { | |
48 | limit = (1UL << 53) - 1; | |
49 | atype = _ASCE_TYPE_REGION2; | |
50 | etype = _REGION2_ENTRY_EMPTY; | |
51 | } else { | |
52 | limit = -1UL; | |
53 | atype = _ASCE_TYPE_REGION1; | |
54 | etype = _REGION1_ENTRY_EMPTY; | |
55 | } | |
56 | gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL); | |
57 | if (!gmap) | |
58 | goto out; | |
59 | INIT_LIST_HEAD(&gmap->crst_list); | |
4be130a0 MS |
60 | INIT_LIST_HEAD(&gmap->children); |
61 | INIT_LIST_HEAD(&gmap->pt_list); | |
1e133ab2 MS |
62 | INIT_RADIX_TREE(&gmap->guest_to_host, GFP_KERNEL); |
63 | INIT_RADIX_TREE(&gmap->host_to_guest, GFP_ATOMIC); | |
4be130a0 | 64 | INIT_RADIX_TREE(&gmap->host_to_rmap, GFP_ATOMIC); |
1e133ab2 | 65 | spin_lock_init(&gmap->guest_table_lock); |
4be130a0 | 66 | spin_lock_init(&gmap->shadow_lock); |
6ea427bb | 67 | atomic_set(&gmap->ref_count, 1); |
1e133ab2 MS |
68 | page = alloc_pages(GFP_KERNEL, 2); |
69 | if (!page) | |
70 | goto out_free; | |
71 | page->index = 0; | |
72 | list_add(&page->lru, &gmap->crst_list); | |
73 | table = (unsigned long *) page_to_phys(page); | |
74 | crst_table_init(table, etype); | |
75 | gmap->table = table; | |
76 | gmap->asce = atype | _ASCE_TABLE_LENGTH | | |
77 | _ASCE_USER_BITS | __pa(table); | |
78 | gmap->asce_end = limit; | |
1e133ab2 MS |
79 | return gmap; |
80 | ||
81 | out_free: | |
82 | kfree(gmap); | |
83 | out: | |
84 | return NULL; | |
85 | } | |
6ea427bb MS |
86 | |
87 | /** | |
88 | * gmap_create - create a guest address space | |
89 | * @mm: pointer to the parent mm_struct | |
90 | * @limit: maximum size of the gmap address space | |
91 | * | |
92 | * Returns a guest address space structure. | |
93 | */ | |
94 | struct gmap *gmap_create(struct mm_struct *mm, unsigned long limit) | |
95 | { | |
96 | struct gmap *gmap; | |
44b6cc81 | 97 | unsigned long gmap_asce; |
6ea427bb MS |
98 | |
99 | gmap = gmap_alloc(limit); | |
100 | if (!gmap) | |
101 | return NULL; | |
102 | gmap->mm = mm; | |
103 | spin_lock(&mm->context.gmap_lock); | |
104 | list_add_rcu(&gmap->list, &mm->context.gmap_list); | |
44b6cc81 MS |
105 | if (list_is_singular(&mm->context.gmap_list)) |
106 | gmap_asce = gmap->asce; | |
107 | else | |
108 | gmap_asce = -1UL; | |
109 | WRITE_ONCE(mm->context.gmap_asce, gmap_asce); | |
6ea427bb MS |
110 | spin_unlock(&mm->context.gmap_lock); |
111 | return gmap; | |
112 | } | |
113 | EXPORT_SYMBOL_GPL(gmap_create); | |
1e133ab2 MS |
114 | |
115 | static void gmap_flush_tlb(struct gmap *gmap) | |
116 | { | |
117 | if (MACHINE_HAS_IDTE) | |
f0454029 | 118 | __tlb_flush_idte(gmap->asce); |
1e133ab2 MS |
119 | else |
120 | __tlb_flush_global(); | |
121 | } | |
122 | ||
123 | static void gmap_radix_tree_free(struct radix_tree_root *root) | |
124 | { | |
125 | struct radix_tree_iter iter; | |
126 | unsigned long indices[16]; | |
127 | unsigned long index; | |
128 | void **slot; | |
129 | int i, nr; | |
130 | ||
131 | /* A radix tree is freed by deleting all of its entries */ | |
132 | index = 0; | |
133 | do { | |
134 | nr = 0; | |
135 | radix_tree_for_each_slot(slot, root, &iter, index) { | |
136 | indices[nr] = iter.index; | |
137 | if (++nr == 16) | |
138 | break; | |
139 | } | |
140 | for (i = 0; i < nr; i++) { | |
141 | index = indices[i]; | |
142 | radix_tree_delete(root, index); | |
143 | } | |
144 | } while (nr > 0); | |
145 | } | |
146 | ||
4be130a0 MS |
147 | static void gmap_rmap_radix_tree_free(struct radix_tree_root *root) |
148 | { | |
149 | struct gmap_rmap *rmap, *rnext, *head; | |
150 | struct radix_tree_iter iter; | |
151 | unsigned long indices[16]; | |
152 | unsigned long index; | |
153 | void **slot; | |
154 | int i, nr; | |
155 | ||
156 | /* A radix tree is freed by deleting all of its entries */ | |
157 | index = 0; | |
158 | do { | |
159 | nr = 0; | |
160 | radix_tree_for_each_slot(slot, root, &iter, index) { | |
161 | indices[nr] = iter.index; | |
162 | if (++nr == 16) | |
163 | break; | |
164 | } | |
165 | for (i = 0; i < nr; i++) { | |
166 | index = indices[i]; | |
167 | head = radix_tree_delete(root, index); | |
168 | gmap_for_each_rmap_safe(rmap, rnext, head) | |
169 | kfree(rmap); | |
170 | } | |
171 | } while (nr > 0); | |
172 | } | |
173 | ||
1e133ab2 MS |
174 | /** |
175 | * gmap_free - free a guest address space | |
176 | * @gmap: pointer to the guest address space structure | |
4be130a0 MS |
177 | * |
178 | * No locks required. There are no references to this gmap anymore. | |
1e133ab2 | 179 | */ |
6ea427bb | 180 | static void gmap_free(struct gmap *gmap) |
1e133ab2 MS |
181 | { |
182 | struct page *page, *next; | |
183 | ||
eea3678d DH |
184 | /* Flush tlb of all gmaps (if not already done for shadows) */ |
185 | if (!(gmap_is_shadow(gmap) && gmap->removed)) | |
186 | gmap_flush_tlb(gmap); | |
1e133ab2 MS |
187 | /* Free all segment & region tables. */ |
188 | list_for_each_entry_safe(page, next, &gmap->crst_list, lru) | |
189 | __free_pages(page, 2); | |
190 | gmap_radix_tree_free(&gmap->guest_to_host); | |
191 | gmap_radix_tree_free(&gmap->host_to_guest); | |
4be130a0 MS |
192 | |
193 | /* Free additional data for a shadow gmap */ | |
194 | if (gmap_is_shadow(gmap)) { | |
195 | /* Free all page tables. */ | |
196 | list_for_each_entry_safe(page, next, &gmap->pt_list, lru) | |
197 | page_table_free_pgste(page); | |
198 | gmap_rmap_radix_tree_free(&gmap->host_to_rmap); | |
199 | /* Release reference to the parent */ | |
200 | gmap_put(gmap->parent); | |
201 | } | |
202 | ||
1e133ab2 MS |
203 | kfree(gmap); |
204 | } | |
6ea427bb MS |
205 | |
206 | /** | |
207 | * gmap_get - increase reference counter for guest address space | |
208 | * @gmap: pointer to the guest address space structure | |
209 | * | |
210 | * Returns the gmap pointer | |
211 | */ | |
212 | struct gmap *gmap_get(struct gmap *gmap) | |
213 | { | |
214 | atomic_inc(&gmap->ref_count); | |
215 | return gmap; | |
216 | } | |
217 | EXPORT_SYMBOL_GPL(gmap_get); | |
218 | ||
219 | /** | |
220 | * gmap_put - decrease reference counter for guest address space | |
221 | * @gmap: pointer to the guest address space structure | |
222 | * | |
223 | * If the reference counter reaches zero the guest address space is freed. | |
224 | */ | |
225 | void gmap_put(struct gmap *gmap) | |
226 | { | |
227 | if (atomic_dec_return(&gmap->ref_count) == 0) | |
228 | gmap_free(gmap); | |
229 | } | |
230 | EXPORT_SYMBOL_GPL(gmap_put); | |
231 | ||
232 | /** | |
233 | * gmap_remove - remove a guest address space but do not free it yet | |
234 | * @gmap: pointer to the guest address space structure | |
235 | */ | |
236 | void gmap_remove(struct gmap *gmap) | |
237 | { | |
4be130a0 | 238 | struct gmap *sg, *next; |
44b6cc81 | 239 | unsigned long gmap_asce; |
4be130a0 | 240 | |
4be130a0 MS |
241 | /* Remove all shadow gmaps linked to this gmap */ |
242 | if (!list_empty(&gmap->children)) { | |
243 | spin_lock(&gmap->shadow_lock); | |
244 | list_for_each_entry_safe(sg, next, &gmap->children, list) { | |
4be130a0 MS |
245 | list_del(&sg->list); |
246 | gmap_put(sg); | |
247 | } | |
248 | spin_unlock(&gmap->shadow_lock); | |
249 | } | |
6ea427bb MS |
250 | /* Remove gmap from the pre-mm list */ |
251 | spin_lock(&gmap->mm->context.gmap_lock); | |
252 | list_del_rcu(&gmap->list); | |
44b6cc81 MS |
253 | if (list_empty(&gmap->mm->context.gmap_list)) |
254 | gmap_asce = 0; | |
255 | else if (list_is_singular(&gmap->mm->context.gmap_list)) | |
256 | gmap_asce = list_first_entry(&gmap->mm->context.gmap_list, | |
257 | struct gmap, list)->asce; | |
258 | else | |
259 | gmap_asce = -1UL; | |
260 | WRITE_ONCE(gmap->mm->context.gmap_asce, gmap_asce); | |
6ea427bb MS |
261 | spin_unlock(&gmap->mm->context.gmap_lock); |
262 | synchronize_rcu(); | |
263 | /* Put reference */ | |
264 | gmap_put(gmap); | |
265 | } | |
266 | EXPORT_SYMBOL_GPL(gmap_remove); | |
1e133ab2 MS |
267 | |
268 | /** | |
269 | * gmap_enable - switch primary space to the guest address space | |
270 | * @gmap: pointer to the guest address space structure | |
271 | */ | |
272 | void gmap_enable(struct gmap *gmap) | |
273 | { | |
274 | S390_lowcore.gmap = (unsigned long) gmap; | |
275 | } | |
276 | EXPORT_SYMBOL_GPL(gmap_enable); | |
277 | ||
278 | /** | |
279 | * gmap_disable - switch back to the standard primary address space | |
280 | * @gmap: pointer to the guest address space structure | |
281 | */ | |
282 | void gmap_disable(struct gmap *gmap) | |
283 | { | |
284 | S390_lowcore.gmap = 0UL; | |
285 | } | |
286 | EXPORT_SYMBOL_GPL(gmap_disable); | |
287 | ||
37d9df98 DH |
288 | /** |
289 | * gmap_get_enabled - get a pointer to the currently enabled gmap | |
290 | * | |
291 | * Returns a pointer to the currently enabled gmap. 0 if none is enabled. | |
292 | */ | |
293 | struct gmap *gmap_get_enabled(void) | |
294 | { | |
295 | return (struct gmap *) S390_lowcore.gmap; | |
296 | } | |
297 | EXPORT_SYMBOL_GPL(gmap_get_enabled); | |
298 | ||
1e133ab2 MS |
299 | /* |
300 | * gmap_alloc_table is assumed to be called with mmap_sem held | |
301 | */ | |
302 | static int gmap_alloc_table(struct gmap *gmap, unsigned long *table, | |
303 | unsigned long init, unsigned long gaddr) | |
304 | { | |
305 | struct page *page; | |
306 | unsigned long *new; | |
307 | ||
308 | /* since we dont free the gmap table until gmap_free we can unlock */ | |
309 | page = alloc_pages(GFP_KERNEL, 2); | |
310 | if (!page) | |
311 | return -ENOMEM; | |
312 | new = (unsigned long *) page_to_phys(page); | |
313 | crst_table_init(new, init); | |
4be130a0 | 314 | spin_lock(&gmap->guest_table_lock); |
1e133ab2 MS |
315 | if (*table & _REGION_ENTRY_INVALID) { |
316 | list_add(&page->lru, &gmap->crst_list); | |
317 | *table = (unsigned long) new | _REGION_ENTRY_LENGTH | | |
318 | (*table & _REGION_ENTRY_TYPE_MASK); | |
319 | page->index = gaddr; | |
320 | page = NULL; | |
321 | } | |
4be130a0 | 322 | spin_unlock(&gmap->guest_table_lock); |
1e133ab2 MS |
323 | if (page) |
324 | __free_pages(page, 2); | |
325 | return 0; | |
326 | } | |
327 | ||
328 | /** | |
329 | * __gmap_segment_gaddr - find virtual address from segment pointer | |
330 | * @entry: pointer to a segment table entry in the guest address space | |
331 | * | |
332 | * Returns the virtual address in the guest address space for the segment | |
333 | */ | |
334 | static unsigned long __gmap_segment_gaddr(unsigned long *entry) | |
335 | { | |
336 | struct page *page; | |
337 | unsigned long offset, mask; | |
338 | ||
339 | offset = (unsigned long) entry / sizeof(unsigned long); | |
340 | offset = (offset & (PTRS_PER_PMD - 1)) * PMD_SIZE; | |
341 | mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); | |
342 | page = virt_to_page((void *)((unsigned long) entry & mask)); | |
343 | return page->index + offset; | |
344 | } | |
345 | ||
346 | /** | |
347 | * __gmap_unlink_by_vmaddr - unlink a single segment via a host address | |
348 | * @gmap: pointer to the guest address space structure | |
349 | * @vmaddr: address in the host process address space | |
350 | * | |
351 | * Returns 1 if a TLB flush is required | |
352 | */ | |
353 | static int __gmap_unlink_by_vmaddr(struct gmap *gmap, unsigned long vmaddr) | |
354 | { | |
355 | unsigned long *entry; | |
356 | int flush = 0; | |
357 | ||
4be130a0 | 358 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
359 | spin_lock(&gmap->guest_table_lock); |
360 | entry = radix_tree_delete(&gmap->host_to_guest, vmaddr >> PMD_SHIFT); | |
361 | if (entry) { | |
362 | flush = (*entry != _SEGMENT_ENTRY_INVALID); | |
363 | *entry = _SEGMENT_ENTRY_INVALID; | |
364 | } | |
365 | spin_unlock(&gmap->guest_table_lock); | |
366 | return flush; | |
367 | } | |
368 | ||
369 | /** | |
370 | * __gmap_unmap_by_gaddr - unmap a single segment via a guest address | |
371 | * @gmap: pointer to the guest address space structure | |
372 | * @gaddr: address in the guest address space | |
373 | * | |
374 | * Returns 1 if a TLB flush is required | |
375 | */ | |
376 | static int __gmap_unmap_by_gaddr(struct gmap *gmap, unsigned long gaddr) | |
377 | { | |
378 | unsigned long vmaddr; | |
379 | ||
380 | vmaddr = (unsigned long) radix_tree_delete(&gmap->guest_to_host, | |
381 | gaddr >> PMD_SHIFT); | |
382 | return vmaddr ? __gmap_unlink_by_vmaddr(gmap, vmaddr) : 0; | |
383 | } | |
384 | ||
385 | /** | |
386 | * gmap_unmap_segment - unmap segment from the guest address space | |
387 | * @gmap: pointer to the guest address space structure | |
388 | * @to: address in the guest address space | |
389 | * @len: length of the memory area to unmap | |
390 | * | |
391 | * Returns 0 if the unmap succeeded, -EINVAL if not. | |
392 | */ | |
393 | int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len) | |
394 | { | |
395 | unsigned long off; | |
396 | int flush; | |
397 | ||
4be130a0 | 398 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
399 | if ((to | len) & (PMD_SIZE - 1)) |
400 | return -EINVAL; | |
401 | if (len == 0 || to + len < to) | |
402 | return -EINVAL; | |
403 | ||
404 | flush = 0; | |
405 | down_write(&gmap->mm->mmap_sem); | |
406 | for (off = 0; off < len; off += PMD_SIZE) | |
407 | flush |= __gmap_unmap_by_gaddr(gmap, to + off); | |
408 | up_write(&gmap->mm->mmap_sem); | |
409 | if (flush) | |
410 | gmap_flush_tlb(gmap); | |
411 | return 0; | |
412 | } | |
413 | EXPORT_SYMBOL_GPL(gmap_unmap_segment); | |
414 | ||
415 | /** | |
416 | * gmap_map_segment - map a segment to the guest address space | |
417 | * @gmap: pointer to the guest address space structure | |
418 | * @from: source address in the parent address space | |
419 | * @to: target address in the guest address space | |
420 | * @len: length of the memory area to map | |
421 | * | |
422 | * Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not. | |
423 | */ | |
424 | int gmap_map_segment(struct gmap *gmap, unsigned long from, | |
425 | unsigned long to, unsigned long len) | |
426 | { | |
427 | unsigned long off; | |
428 | int flush; | |
429 | ||
4be130a0 | 430 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
431 | if ((from | to | len) & (PMD_SIZE - 1)) |
432 | return -EINVAL; | |
433 | if (len == 0 || from + len < from || to + len < to || | |
9c650d09 | 434 | from + len - 1 > TASK_MAX_SIZE || to + len - 1 > gmap->asce_end) |
1e133ab2 MS |
435 | return -EINVAL; |
436 | ||
437 | flush = 0; | |
438 | down_write(&gmap->mm->mmap_sem); | |
439 | for (off = 0; off < len; off += PMD_SIZE) { | |
440 | /* Remove old translation */ | |
441 | flush |= __gmap_unmap_by_gaddr(gmap, to + off); | |
442 | /* Store new translation */ | |
443 | if (radix_tree_insert(&gmap->guest_to_host, | |
444 | (to + off) >> PMD_SHIFT, | |
445 | (void *) from + off)) | |
446 | break; | |
447 | } | |
448 | up_write(&gmap->mm->mmap_sem); | |
449 | if (flush) | |
450 | gmap_flush_tlb(gmap); | |
451 | if (off >= len) | |
452 | return 0; | |
453 | gmap_unmap_segment(gmap, to, len); | |
454 | return -ENOMEM; | |
455 | } | |
456 | EXPORT_SYMBOL_GPL(gmap_map_segment); | |
457 | ||
458 | /** | |
459 | * __gmap_translate - translate a guest address to a user space address | |
460 | * @gmap: pointer to guest mapping meta data structure | |
461 | * @gaddr: guest address | |
462 | * | |
463 | * Returns user space address which corresponds to the guest address or | |
464 | * -EFAULT if no such mapping exists. | |
465 | * This function does not establish potentially missing page table entries. | |
466 | * The mmap_sem of the mm that belongs to the address space must be held | |
467 | * when this function gets called. | |
4be130a0 MS |
468 | * |
469 | * Note: Can also be called for shadow gmaps. | |
1e133ab2 MS |
470 | */ |
471 | unsigned long __gmap_translate(struct gmap *gmap, unsigned long gaddr) | |
472 | { | |
473 | unsigned long vmaddr; | |
474 | ||
475 | vmaddr = (unsigned long) | |
476 | radix_tree_lookup(&gmap->guest_to_host, gaddr >> PMD_SHIFT); | |
4be130a0 | 477 | /* Note: guest_to_host is empty for a shadow gmap */ |
1e133ab2 MS |
478 | return vmaddr ? (vmaddr | (gaddr & ~PMD_MASK)) : -EFAULT; |
479 | } | |
480 | EXPORT_SYMBOL_GPL(__gmap_translate); | |
481 | ||
482 | /** | |
483 | * gmap_translate - translate a guest address to a user space address | |
484 | * @gmap: pointer to guest mapping meta data structure | |
485 | * @gaddr: guest address | |
486 | * | |
487 | * Returns user space address which corresponds to the guest address or | |
488 | * -EFAULT if no such mapping exists. | |
489 | * This function does not establish potentially missing page table entries. | |
490 | */ | |
491 | unsigned long gmap_translate(struct gmap *gmap, unsigned long gaddr) | |
492 | { | |
493 | unsigned long rc; | |
494 | ||
495 | down_read(&gmap->mm->mmap_sem); | |
496 | rc = __gmap_translate(gmap, gaddr); | |
497 | up_read(&gmap->mm->mmap_sem); | |
498 | return rc; | |
499 | } | |
500 | EXPORT_SYMBOL_GPL(gmap_translate); | |
501 | ||
502 | /** | |
503 | * gmap_unlink - disconnect a page table from the gmap shadow tables | |
504 | * @gmap: pointer to guest mapping meta data structure | |
505 | * @table: pointer to the host page table | |
506 | * @vmaddr: vm address associated with the host page table | |
507 | */ | |
508 | void gmap_unlink(struct mm_struct *mm, unsigned long *table, | |
509 | unsigned long vmaddr) | |
510 | { | |
511 | struct gmap *gmap; | |
512 | int flush; | |
513 | ||
8ecb1a59 MS |
514 | rcu_read_lock(); |
515 | list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { | |
1e133ab2 MS |
516 | flush = __gmap_unlink_by_vmaddr(gmap, vmaddr); |
517 | if (flush) | |
518 | gmap_flush_tlb(gmap); | |
519 | } | |
8ecb1a59 | 520 | rcu_read_unlock(); |
1e133ab2 MS |
521 | } |
522 | ||
523 | /** | |
524 | * gmap_link - set up shadow page tables to connect a host to a guest address | |
525 | * @gmap: pointer to guest mapping meta data structure | |
526 | * @gaddr: guest address | |
527 | * @vmaddr: vm address | |
528 | * | |
529 | * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT | |
530 | * if the vm address is already mapped to a different guest segment. | |
531 | * The mmap_sem of the mm that belongs to the address space must be held | |
532 | * when this function gets called. | |
533 | */ | |
534 | int __gmap_link(struct gmap *gmap, unsigned long gaddr, unsigned long vmaddr) | |
535 | { | |
536 | struct mm_struct *mm; | |
537 | unsigned long *table; | |
538 | spinlock_t *ptl; | |
539 | pgd_t *pgd; | |
540 | pud_t *pud; | |
541 | pmd_t *pmd; | |
542 | int rc; | |
543 | ||
4be130a0 | 544 | BUG_ON(gmap_is_shadow(gmap)); |
1e133ab2 MS |
545 | /* Create higher level tables in the gmap page table */ |
546 | table = gmap->table; | |
547 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION1) { | |
548 | table += (gaddr >> 53) & 0x7ff; | |
549 | if ((*table & _REGION_ENTRY_INVALID) && | |
550 | gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY, | |
551 | gaddr & 0xffe0000000000000UL)) | |
552 | return -ENOMEM; | |
553 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
554 | } | |
555 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION2) { | |
556 | table += (gaddr >> 42) & 0x7ff; | |
557 | if ((*table & _REGION_ENTRY_INVALID) && | |
558 | gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY, | |
559 | gaddr & 0xfffffc0000000000UL)) | |
560 | return -ENOMEM; | |
561 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
562 | } | |
563 | if ((gmap->asce & _ASCE_TYPE_MASK) >= _ASCE_TYPE_REGION3) { | |
564 | table += (gaddr >> 31) & 0x7ff; | |
565 | if ((*table & _REGION_ENTRY_INVALID) && | |
566 | gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY, | |
567 | gaddr & 0xffffffff80000000UL)) | |
568 | return -ENOMEM; | |
569 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
570 | } | |
571 | table += (gaddr >> 20) & 0x7ff; | |
572 | /* Walk the parent mm page table */ | |
573 | mm = gmap->mm; | |
574 | pgd = pgd_offset(mm, vmaddr); | |
575 | VM_BUG_ON(pgd_none(*pgd)); | |
576 | pud = pud_offset(pgd, vmaddr); | |
577 | VM_BUG_ON(pud_none(*pud)); | |
d08de8e2 GS |
578 | /* large puds cannot yet be handled */ |
579 | if (pud_large(*pud)) | |
580 | return -EFAULT; | |
1e133ab2 MS |
581 | pmd = pmd_offset(pud, vmaddr); |
582 | VM_BUG_ON(pmd_none(*pmd)); | |
583 | /* large pmds cannot yet be handled */ | |
584 | if (pmd_large(*pmd)) | |
585 | return -EFAULT; | |
586 | /* Link gmap segment table entry location to page table. */ | |
587 | rc = radix_tree_preload(GFP_KERNEL); | |
588 | if (rc) | |
589 | return rc; | |
590 | ptl = pmd_lock(mm, pmd); | |
591 | spin_lock(&gmap->guest_table_lock); | |
592 | if (*table == _SEGMENT_ENTRY_INVALID) { | |
593 | rc = radix_tree_insert(&gmap->host_to_guest, | |
594 | vmaddr >> PMD_SHIFT, table); | |
595 | if (!rc) | |
596 | *table = pmd_val(*pmd); | |
597 | } else | |
598 | rc = 0; | |
599 | spin_unlock(&gmap->guest_table_lock); | |
600 | spin_unlock(ptl); | |
601 | radix_tree_preload_end(); | |
602 | return rc; | |
603 | } | |
604 | ||
605 | /** | |
606 | * gmap_fault - resolve a fault on a guest address | |
607 | * @gmap: pointer to guest mapping meta data structure | |
608 | * @gaddr: guest address | |
609 | * @fault_flags: flags to pass down to handle_mm_fault() | |
610 | * | |
611 | * Returns 0 on success, -ENOMEM for out of memory conditions, and -EFAULT | |
612 | * if the vm address is already mapped to a different guest segment. | |
613 | */ | |
614 | int gmap_fault(struct gmap *gmap, unsigned long gaddr, | |
615 | unsigned int fault_flags) | |
616 | { | |
617 | unsigned long vmaddr; | |
618 | int rc; | |
619 | bool unlocked; | |
620 | ||
621 | down_read(&gmap->mm->mmap_sem); | |
622 | ||
623 | retry: | |
624 | unlocked = false; | |
625 | vmaddr = __gmap_translate(gmap, gaddr); | |
626 | if (IS_ERR_VALUE(vmaddr)) { | |
627 | rc = vmaddr; | |
628 | goto out_up; | |
629 | } | |
630 | if (fixup_user_fault(current, gmap->mm, vmaddr, fault_flags, | |
631 | &unlocked)) { | |
632 | rc = -EFAULT; | |
633 | goto out_up; | |
634 | } | |
635 | /* | |
636 | * In the case that fixup_user_fault unlocked the mmap_sem during | |
637 | * faultin redo __gmap_translate to not race with a map/unmap_segment. | |
638 | */ | |
639 | if (unlocked) | |
640 | goto retry; | |
641 | ||
642 | rc = __gmap_link(gmap, gaddr, vmaddr); | |
643 | out_up: | |
644 | up_read(&gmap->mm->mmap_sem); | |
645 | return rc; | |
646 | } | |
647 | EXPORT_SYMBOL_GPL(gmap_fault); | |
648 | ||
649 | /* | |
650 | * this function is assumed to be called with mmap_sem held | |
651 | */ | |
652 | void __gmap_zap(struct gmap *gmap, unsigned long gaddr) | |
653 | { | |
654 | unsigned long vmaddr; | |
655 | spinlock_t *ptl; | |
656 | pte_t *ptep; | |
657 | ||
658 | /* Find the vm address for the guest address */ | |
659 | vmaddr = (unsigned long) radix_tree_lookup(&gmap->guest_to_host, | |
660 | gaddr >> PMD_SHIFT); | |
661 | if (vmaddr) { | |
662 | vmaddr |= gaddr & ~PMD_MASK; | |
663 | /* Get pointer to the page table entry */ | |
664 | ptep = get_locked_pte(gmap->mm, vmaddr, &ptl); | |
665 | if (likely(ptep)) | |
666 | ptep_zap_unused(gmap->mm, vmaddr, ptep, 0); | |
667 | pte_unmap_unlock(ptep, ptl); | |
668 | } | |
669 | } | |
670 | EXPORT_SYMBOL_GPL(__gmap_zap); | |
671 | ||
672 | void gmap_discard(struct gmap *gmap, unsigned long from, unsigned long to) | |
673 | { | |
674 | unsigned long gaddr, vmaddr, size; | |
675 | struct vm_area_struct *vma; | |
676 | ||
677 | down_read(&gmap->mm->mmap_sem); | |
678 | for (gaddr = from; gaddr < to; | |
679 | gaddr = (gaddr + PMD_SIZE) & PMD_MASK) { | |
680 | /* Find the vm address for the guest address */ | |
681 | vmaddr = (unsigned long) | |
682 | radix_tree_lookup(&gmap->guest_to_host, | |
683 | gaddr >> PMD_SHIFT); | |
684 | if (!vmaddr) | |
685 | continue; | |
686 | vmaddr |= gaddr & ~PMD_MASK; | |
687 | /* Find vma in the parent mm */ | |
688 | vma = find_vma(gmap->mm, vmaddr); | |
689 | size = min(to - gaddr, PMD_SIZE - (gaddr & ~PMD_MASK)); | |
690 | zap_page_range(vma, vmaddr, size, NULL); | |
691 | } | |
692 | up_read(&gmap->mm->mmap_sem); | |
693 | } | |
694 | EXPORT_SYMBOL_GPL(gmap_discard); | |
695 | ||
696 | static LIST_HEAD(gmap_notifier_list); | |
697 | static DEFINE_SPINLOCK(gmap_notifier_lock); | |
698 | ||
699 | /** | |
b2d73b2a | 700 | * gmap_register_pte_notifier - register a pte invalidation callback |
1e133ab2 MS |
701 | * @nb: pointer to the gmap notifier block |
702 | */ | |
b2d73b2a | 703 | void gmap_register_pte_notifier(struct gmap_notifier *nb) |
1e133ab2 MS |
704 | { |
705 | spin_lock(&gmap_notifier_lock); | |
8ecb1a59 | 706 | list_add_rcu(&nb->list, &gmap_notifier_list); |
1e133ab2 MS |
707 | spin_unlock(&gmap_notifier_lock); |
708 | } | |
b2d73b2a | 709 | EXPORT_SYMBOL_GPL(gmap_register_pte_notifier); |
1e133ab2 MS |
710 | |
711 | /** | |
b2d73b2a | 712 | * gmap_unregister_pte_notifier - remove a pte invalidation callback |
1e133ab2 MS |
713 | * @nb: pointer to the gmap notifier block |
714 | */ | |
b2d73b2a | 715 | void gmap_unregister_pte_notifier(struct gmap_notifier *nb) |
1e133ab2 MS |
716 | { |
717 | spin_lock(&gmap_notifier_lock); | |
8ecb1a59 | 718 | list_del_rcu(&nb->list); |
1e133ab2 | 719 | spin_unlock(&gmap_notifier_lock); |
8ecb1a59 | 720 | synchronize_rcu(); |
1e133ab2 | 721 | } |
b2d73b2a | 722 | EXPORT_SYMBOL_GPL(gmap_unregister_pte_notifier); |
1e133ab2 | 723 | |
414d3b07 MS |
724 | /** |
725 | * gmap_call_notifier - call all registered invalidation callbacks | |
726 | * @gmap: pointer to guest mapping meta data structure | |
727 | * @start: start virtual address in the guest address space | |
728 | * @end: end virtual address in the guest address space | |
729 | */ | |
730 | static void gmap_call_notifier(struct gmap *gmap, unsigned long start, | |
731 | unsigned long end) | |
732 | { | |
733 | struct gmap_notifier *nb; | |
734 | ||
735 | list_for_each_entry(nb, &gmap_notifier_list, list) | |
736 | nb->notifier_call(gmap, start, end); | |
737 | } | |
738 | ||
1e133ab2 | 739 | /** |
b2d73b2a MS |
740 | * gmap_table_walk - walk the gmap page tables |
741 | * @gmap: pointer to guest mapping meta data structure | |
742 | * @gaddr: virtual address in the guest address space | |
4be130a0 MS |
743 | * @level: page table level to stop at |
744 | * | |
745 | * Returns a table entry pointer for the given guest address and @level | |
746 | * @level=0 : returns a pointer to a page table table entry (or NULL) | |
747 | * @level=1 : returns a pointer to a segment table entry (or NULL) | |
748 | * @level=2 : returns a pointer to a region-3 table entry (or NULL) | |
749 | * @level=3 : returns a pointer to a region-2 table entry (or NULL) | |
750 | * @level=4 : returns a pointer to a region-1 table entry (or NULL) | |
751 | * | |
752 | * Returns NULL if the gmap page tables could not be walked to the | |
753 | * requested level. | |
b2d73b2a | 754 | * |
4be130a0 | 755 | * Note: Can also be called for shadow gmaps. |
b2d73b2a MS |
756 | */ |
757 | static inline unsigned long *gmap_table_walk(struct gmap *gmap, | |
4be130a0 | 758 | unsigned long gaddr, int level) |
b2d73b2a MS |
759 | { |
760 | unsigned long *table; | |
761 | ||
4be130a0 MS |
762 | if ((gmap->asce & _ASCE_TYPE_MASK) + 4 < (level * 4)) |
763 | return NULL; | |
764 | if (gmap_is_shadow(gmap) && gmap->removed) | |
765 | return NULL; | |
766 | if (gaddr & (-1UL << (31 + ((gmap->asce & _ASCE_TYPE_MASK) >> 2)*11))) | |
767 | return NULL; | |
b2d73b2a MS |
768 | table = gmap->table; |
769 | switch (gmap->asce & _ASCE_TYPE_MASK) { | |
770 | case _ASCE_TYPE_REGION1: | |
771 | table += (gaddr >> 53) & 0x7ff; | |
4be130a0 MS |
772 | if (level == 4) |
773 | break; | |
b2d73b2a MS |
774 | if (*table & _REGION_ENTRY_INVALID) |
775 | return NULL; | |
776 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
777 | /* Fallthrough */ | |
778 | case _ASCE_TYPE_REGION2: | |
779 | table += (gaddr >> 42) & 0x7ff; | |
4be130a0 MS |
780 | if (level == 3) |
781 | break; | |
b2d73b2a MS |
782 | if (*table & _REGION_ENTRY_INVALID) |
783 | return NULL; | |
784 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
785 | /* Fallthrough */ | |
786 | case _ASCE_TYPE_REGION3: | |
787 | table += (gaddr >> 31) & 0x7ff; | |
4be130a0 MS |
788 | if (level == 2) |
789 | break; | |
b2d73b2a MS |
790 | if (*table & _REGION_ENTRY_INVALID) |
791 | return NULL; | |
792 | table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN); | |
793 | /* Fallthrough */ | |
794 | case _ASCE_TYPE_SEGMENT: | |
795 | table += (gaddr >> 20) & 0x7ff; | |
4be130a0 MS |
796 | if (level == 1) |
797 | break; | |
798 | if (*table & _REGION_ENTRY_INVALID) | |
799 | return NULL; | |
800 | table = (unsigned long *)(*table & _SEGMENT_ENTRY_ORIGIN); | |
801 | table += (gaddr >> 12) & 0xff; | |
b2d73b2a MS |
802 | } |
803 | return table; | |
804 | } | |
805 | ||
806 | /** | |
807 | * gmap_pte_op_walk - walk the gmap page table, get the page table lock | |
808 | * and return the pte pointer | |
809 | * @gmap: pointer to guest mapping meta data structure | |
810 | * @gaddr: virtual address in the guest address space | |
811 | * @ptl: pointer to the spinlock pointer | |
812 | * | |
813 | * Returns a pointer to the locked pte for a guest address, or NULL | |
4be130a0 MS |
814 | * |
815 | * Note: Can also be called for shadow gmaps. | |
b2d73b2a MS |
816 | */ |
817 | static pte_t *gmap_pte_op_walk(struct gmap *gmap, unsigned long gaddr, | |
818 | spinlock_t **ptl) | |
819 | { | |
820 | unsigned long *table; | |
821 | ||
4be130a0 MS |
822 | if (gmap_is_shadow(gmap)) |
823 | spin_lock(&gmap->guest_table_lock); | |
b2d73b2a | 824 | /* Walk the gmap page table, lock and get pte pointer */ |
4be130a0 MS |
825 | table = gmap_table_walk(gmap, gaddr, 1); /* get segment pointer */ |
826 | if (!table || *table & _SEGMENT_ENTRY_INVALID) { | |
827 | if (gmap_is_shadow(gmap)) | |
828 | spin_unlock(&gmap->guest_table_lock); | |
b2d73b2a | 829 | return NULL; |
4be130a0 MS |
830 | } |
831 | if (gmap_is_shadow(gmap)) { | |
832 | *ptl = &gmap->guest_table_lock; | |
833 | return pte_offset_map((pmd_t *) table, gaddr); | |
834 | } | |
b2d73b2a MS |
835 | return pte_alloc_map_lock(gmap->mm, (pmd_t *) table, gaddr, ptl); |
836 | } | |
837 | ||
838 | /** | |
839 | * gmap_pte_op_fixup - force a page in and connect the gmap page table | |
840 | * @gmap: pointer to guest mapping meta data structure | |
841 | * @gaddr: virtual address in the guest address space | |
842 | * @vmaddr: address in the host process address space | |
01f71917 | 843 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
b2d73b2a MS |
844 | * |
845 | * Returns 0 if the caller can retry __gmap_translate (might fail again), | |
846 | * -ENOMEM if out of memory and -EFAULT if anything goes wrong while fixing | |
847 | * up or connecting the gmap page table. | |
848 | */ | |
849 | static int gmap_pte_op_fixup(struct gmap *gmap, unsigned long gaddr, | |
01f71917 | 850 | unsigned long vmaddr, int prot) |
b2d73b2a MS |
851 | { |
852 | struct mm_struct *mm = gmap->mm; | |
01f71917 | 853 | unsigned int fault_flags; |
b2d73b2a MS |
854 | bool unlocked = false; |
855 | ||
4be130a0 | 856 | BUG_ON(gmap_is_shadow(gmap)); |
01f71917 DH |
857 | fault_flags = (prot == PROT_WRITE) ? FAULT_FLAG_WRITE : 0; |
858 | if (fixup_user_fault(current, mm, vmaddr, fault_flags, &unlocked)) | |
b2d73b2a MS |
859 | return -EFAULT; |
860 | if (unlocked) | |
861 | /* lost mmap_sem, caller has to retry __gmap_translate */ | |
862 | return 0; | |
863 | /* Connect the page tables */ | |
864 | return __gmap_link(gmap, gaddr, vmaddr); | |
1e133ab2 | 865 | } |
1e133ab2 MS |
866 | |
867 | /** | |
b2d73b2a MS |
868 | * gmap_pte_op_end - release the page table lock |
869 | * @ptl: pointer to the spinlock pointer | |
870 | */ | |
871 | static void gmap_pte_op_end(spinlock_t *ptl) | |
872 | { | |
873 | spin_unlock(ptl); | |
874 | } | |
875 | ||
4be130a0 MS |
876 | /* |
877 | * gmap_protect_range - remove access rights to memory and set pgste bits | |
1e133ab2 MS |
878 | * @gmap: pointer to guest mapping meta data structure |
879 | * @gaddr: virtual address in the guest address space | |
880 | * @len: size of area | |
4be130a0 MS |
881 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
882 | * @bits: pgste notification bits to set | |
883 | * | |
884 | * Returns 0 if successfully protected, -ENOMEM if out of memory and | |
885 | * -EFAULT if gaddr is invalid (or mapping for shadows is missing). | |
886 | * | |
887 | * Called with sg->mm->mmap_sem in read. | |
1e133ab2 | 888 | * |
4be130a0 | 889 | * Note: Can also be called for shadow gmaps. |
1e133ab2 | 890 | */ |
4be130a0 MS |
891 | static int gmap_protect_range(struct gmap *gmap, unsigned long gaddr, |
892 | unsigned long len, int prot, unsigned long bits) | |
1e133ab2 | 893 | { |
4be130a0 | 894 | unsigned long vmaddr; |
1e133ab2 MS |
895 | spinlock_t *ptl; |
896 | pte_t *ptep; | |
4be130a0 MS |
897 | int rc; |
898 | ||
899 | while (len) { | |
900 | rc = -EAGAIN; | |
901 | ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); | |
902 | if (ptep) { | |
903 | rc = ptep_force_prot(gmap->mm, gaddr, ptep, prot, bits); | |
904 | gmap_pte_op_end(ptl); | |
905 | } | |
906 | if (rc) { | |
907 | vmaddr = __gmap_translate(gmap, gaddr); | |
908 | if (IS_ERR_VALUE(vmaddr)) | |
909 | return vmaddr; | |
01f71917 | 910 | rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, prot); |
4be130a0 MS |
911 | if (rc) |
912 | return rc; | |
913 | continue; | |
914 | } | |
915 | gaddr += PAGE_SIZE; | |
916 | len -= PAGE_SIZE; | |
917 | } | |
918 | return 0; | |
919 | } | |
1e133ab2 | 920 | |
b2d73b2a MS |
921 | /** |
922 | * gmap_mprotect_notify - change access rights for a range of ptes and | |
923 | * call the notifier if any pte changes again | |
1e133ab2 MS |
924 | * @gmap: pointer to guest mapping meta data structure |
925 | * @gaddr: virtual address in the guest address space | |
926 | * @len: size of area | |
b2d73b2a | 927 | * @prot: indicates access rights: PROT_NONE, PROT_READ or PROT_WRITE |
1e133ab2 | 928 | * |
b2d73b2a MS |
929 | * Returns 0 if for each page in the given range a gmap mapping exists, |
930 | * the new access rights could be set and the notifier could be armed. | |
931 | * If the gmap mapping is missing for one or more pages -EFAULT is | |
932 | * returned. If no memory could be allocated -ENOMEM is returned. | |
933 | * This function establishes missing page table entries. | |
1e133ab2 | 934 | */ |
b2d73b2a MS |
935 | int gmap_mprotect_notify(struct gmap *gmap, unsigned long gaddr, |
936 | unsigned long len, int prot) | |
1e133ab2 | 937 | { |
4be130a0 | 938 | int rc; |
1e133ab2 | 939 | |
4be130a0 | 940 | if ((gaddr & ~PAGE_MASK) || (len & ~PAGE_MASK) || gmap_is_shadow(gmap)) |
1e133ab2 | 941 | return -EINVAL; |
b2d73b2a | 942 | if (!MACHINE_HAS_ESOP && prot == PROT_READ) |
1e133ab2 MS |
943 | return -EINVAL; |
944 | down_read(&gmap->mm->mmap_sem); | |
4be130a0 MS |
945 | rc = gmap_protect_range(gmap, gaddr, len, prot, PGSTE_IN_BIT); |
946 | up_read(&gmap->mm->mmap_sem); | |
947 | return rc; | |
948 | } | |
949 | EXPORT_SYMBOL_GPL(gmap_mprotect_notify); | |
950 | ||
951 | /** | |
952 | * gmap_read_table - get an unsigned long value from a guest page table using | |
953 | * absolute addressing, without marking the page referenced. | |
954 | * @gmap: pointer to guest mapping meta data structure | |
955 | * @gaddr: virtual address in the guest address space | |
956 | * @val: pointer to the unsigned long value to return | |
957 | * | |
958 | * Returns 0 if the value was read, -ENOMEM if out of memory and -EFAULT | |
959 | * if reading using the virtual address failed. | |
960 | * | |
961 | * Called with gmap->mm->mmap_sem in read. | |
962 | */ | |
963 | int gmap_read_table(struct gmap *gmap, unsigned long gaddr, unsigned long *val) | |
964 | { | |
965 | unsigned long address, vmaddr; | |
966 | spinlock_t *ptl; | |
967 | pte_t *ptep, pte; | |
968 | int rc; | |
969 | ||
970 | while (1) { | |
b2d73b2a MS |
971 | rc = -EAGAIN; |
972 | ptep = gmap_pte_op_walk(gmap, gaddr, &ptl); | |
973 | if (ptep) { | |
4be130a0 MS |
974 | pte = *ptep; |
975 | if (pte_present(pte) && (pte_val(pte) & _PAGE_READ)) { | |
976 | address = pte_val(pte) & PAGE_MASK; | |
977 | address += gaddr & ~PAGE_MASK; | |
978 | *val = *(unsigned long *) address; | |
979 | pte_val(*ptep) |= _PAGE_YOUNG; | |
980 | /* Do *NOT* clear the _PAGE_INVALID bit! */ | |
981 | rc = 0; | |
982 | } | |
b2d73b2a | 983 | gmap_pte_op_end(ptl); |
1e133ab2 | 984 | } |
4be130a0 MS |
985 | if (!rc) |
986 | break; | |
987 | vmaddr = __gmap_translate(gmap, gaddr); | |
988 | if (IS_ERR_VALUE(vmaddr)) { | |
989 | rc = vmaddr; | |
1e133ab2 MS |
990 | break; |
991 | } | |
01f71917 | 992 | rc = gmap_pte_op_fixup(gmap, gaddr, vmaddr, PROT_READ); |
1e133ab2 MS |
993 | if (rc) |
994 | break; | |
1e133ab2 | 995 | } |
1e133ab2 MS |
996 | return rc; |
997 | } | |
4be130a0 | 998 | EXPORT_SYMBOL_GPL(gmap_read_table); |
1e133ab2 MS |
999 | |
1000 | /** | |
4be130a0 MS |
1001 | * gmap_insert_rmap - add a rmap to the host_to_rmap radix tree |
1002 | * @sg: pointer to the shadow guest address space structure | |
1003 | * @vmaddr: vm address associated with the rmap | |
1004 | * @rmap: pointer to the rmap structure | |
1e133ab2 | 1005 | * |
4be130a0 | 1006 | * Called with the sg->guest_table_lock |
1e133ab2 | 1007 | */ |
4be130a0 MS |
1008 | static inline void gmap_insert_rmap(struct gmap *sg, unsigned long vmaddr, |
1009 | struct gmap_rmap *rmap) | |
1e133ab2 | 1010 | { |
4be130a0 | 1011 | void **slot; |
1e133ab2 | 1012 | |
4be130a0 MS |
1013 | BUG_ON(!gmap_is_shadow(sg)); |
1014 | slot = radix_tree_lookup_slot(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT); | |
1015 | if (slot) { | |
1016 | rmap->next = radix_tree_deref_slot_protected(slot, | |
1017 | &sg->guest_table_lock); | |
6d75f366 | 1018 | radix_tree_replace_slot(&sg->host_to_rmap, slot, rmap); |
4be130a0 MS |
1019 | } else { |
1020 | rmap->next = NULL; | |
1021 | radix_tree_insert(&sg->host_to_rmap, vmaddr >> PAGE_SHIFT, | |
1022 | rmap); | |
1023 | } | |
1024 | } | |
1025 | ||
1026 | /** | |
1027 | * gmap_protect_rmap - modify access rights to memory and create an rmap | |
1028 | * @sg: pointer to the shadow guest address space structure | |
1029 | * @raddr: rmap address in the shadow gmap | |
1030 | * @paddr: address in the parent guest address space | |
1031 | * @len: length of the memory area to protect | |
1032 | * @prot: indicates access rights: none, read-only or read-write | |
1033 | * | |
1034 | * Returns 0 if successfully protected and the rmap was created, -ENOMEM | |
1035 | * if out of memory and -EFAULT if paddr is invalid. | |
1036 | */ | |
1037 | static int gmap_protect_rmap(struct gmap *sg, unsigned long raddr, | |
1038 | unsigned long paddr, unsigned long len, int prot) | |
1039 | { | |
1040 | struct gmap *parent; | |
1041 | struct gmap_rmap *rmap; | |
1042 | unsigned long vmaddr; | |
1043 | spinlock_t *ptl; | |
1044 | pte_t *ptep; | |
1045 | int rc; | |
1046 | ||
1047 | BUG_ON(!gmap_is_shadow(sg)); | |
1048 | parent = sg->parent; | |
1049 | while (len) { | |
1050 | vmaddr = __gmap_translate(parent, paddr); | |
1051 | if (IS_ERR_VALUE(vmaddr)) | |
1052 | return vmaddr; | |
1053 | rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); | |
1054 | if (!rmap) | |
1055 | return -ENOMEM; | |
1056 | rmap->raddr = raddr; | |
1057 | rc = radix_tree_preload(GFP_KERNEL); | |
b2d73b2a | 1058 | if (rc) { |
4be130a0 MS |
1059 | kfree(rmap); |
1060 | return rc; | |
1061 | } | |
1062 | rc = -EAGAIN; | |
1063 | ptep = gmap_pte_op_walk(parent, paddr, &ptl); | |
1064 | if (ptep) { | |
1065 | spin_lock(&sg->guest_table_lock); | |
1066 | rc = ptep_force_prot(parent->mm, paddr, ptep, prot, | |
1067 | PGSTE_VSIE_BIT); | |
1068 | if (!rc) | |
1069 | gmap_insert_rmap(sg, vmaddr, rmap); | |
1070 | spin_unlock(&sg->guest_table_lock); | |
1071 | gmap_pte_op_end(ptl); | |
1072 | } | |
1073 | radix_tree_preload_end(); | |
1074 | if (rc) { | |
1075 | kfree(rmap); | |
01f71917 | 1076 | rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); |
b2d73b2a | 1077 | if (rc) |
4be130a0 | 1078 | return rc; |
1e133ab2 | 1079 | continue; |
1e133ab2 | 1080 | } |
4be130a0 | 1081 | paddr += PAGE_SIZE; |
b2d73b2a | 1082 | len -= PAGE_SIZE; |
1e133ab2 | 1083 | } |
4be130a0 MS |
1084 | return 0; |
1085 | } | |
1086 | ||
1087 | #define _SHADOW_RMAP_MASK 0x7 | |
1088 | #define _SHADOW_RMAP_REGION1 0x5 | |
1089 | #define _SHADOW_RMAP_REGION2 0x4 | |
1090 | #define _SHADOW_RMAP_REGION3 0x3 | |
1091 | #define _SHADOW_RMAP_SEGMENT 0x2 | |
1092 | #define _SHADOW_RMAP_PGTABLE 0x1 | |
1093 | ||
1094 | /** | |
1095 | * gmap_idte_one - invalidate a single region or segment table entry | |
1096 | * @asce: region or segment table *origin* + table-type bits | |
1097 | * @vaddr: virtual address to identify the table entry to flush | |
1098 | * | |
1099 | * The invalid bit of a single region or segment table entry is set | |
1100 | * and the associated TLB entries depending on the entry are flushed. | |
1101 | * The table-type of the @asce identifies the portion of the @vaddr | |
1102 | * that is used as the invalidation index. | |
1103 | */ | |
1104 | static inline void gmap_idte_one(unsigned long asce, unsigned long vaddr) | |
1105 | { | |
1106 | asm volatile( | |
1107 | " .insn rrf,0xb98e0000,%0,%1,0,0" | |
1108 | : : "a" (asce), "a" (vaddr) : "cc", "memory"); | |
1109 | } | |
1110 | ||
1111 | /** | |
1112 | * gmap_unshadow_page - remove a page from a shadow page table | |
1113 | * @sg: pointer to the shadow guest address space structure | |
1114 | * @raddr: rmap address in the shadow guest address space | |
1115 | * | |
1116 | * Called with the sg->guest_table_lock | |
1117 | */ | |
1118 | static void gmap_unshadow_page(struct gmap *sg, unsigned long raddr) | |
1119 | { | |
1120 | unsigned long *table; | |
1121 | ||
1122 | BUG_ON(!gmap_is_shadow(sg)); | |
1123 | table = gmap_table_walk(sg, raddr, 0); /* get page table pointer */ | |
1124 | if (!table || *table & _PAGE_INVALID) | |
1125 | return; | |
1126 | gmap_call_notifier(sg, raddr, raddr + (1UL << 12) - 1); | |
1127 | ptep_unshadow_pte(sg->mm, raddr, (pte_t *) table); | |
1128 | } | |
1129 | ||
1130 | /** | |
1131 | * __gmap_unshadow_pgt - remove all entries from a shadow page table | |
1132 | * @sg: pointer to the shadow guest address space structure | |
1133 | * @raddr: rmap address in the shadow guest address space | |
1134 | * @pgt: pointer to the start of a shadow page table | |
1135 | * | |
1136 | * Called with the sg->guest_table_lock | |
1137 | */ | |
1138 | static void __gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr, | |
1139 | unsigned long *pgt) | |
1140 | { | |
1141 | int i; | |
1142 | ||
1143 | BUG_ON(!gmap_is_shadow(sg)); | |
1144 | for (i = 0; i < 256; i++, raddr += 1UL << 12) | |
1145 | pgt[i] = _PAGE_INVALID; | |
1146 | } | |
1147 | ||
1148 | /** | |
1149 | * gmap_unshadow_pgt - remove a shadow page table from a segment entry | |
1150 | * @sg: pointer to the shadow guest address space structure | |
1151 | * @raddr: address in the shadow guest address space | |
1152 | * | |
1153 | * Called with the sg->guest_table_lock | |
1154 | */ | |
1155 | static void gmap_unshadow_pgt(struct gmap *sg, unsigned long raddr) | |
1156 | { | |
1157 | unsigned long sto, *ste, *pgt; | |
1158 | struct page *page; | |
1159 | ||
1160 | BUG_ON(!gmap_is_shadow(sg)); | |
1161 | ste = gmap_table_walk(sg, raddr, 1); /* get segment pointer */ | |
998f637c | 1162 | if (!ste || !(*ste & _SEGMENT_ENTRY_ORIGIN)) |
4be130a0 MS |
1163 | return; |
1164 | gmap_call_notifier(sg, raddr, raddr + (1UL << 20) - 1); | |
1165 | sto = (unsigned long) (ste - ((raddr >> 20) & 0x7ff)); | |
1166 | gmap_idte_one(sto | _ASCE_TYPE_SEGMENT, raddr); | |
1167 | pgt = (unsigned long *)(*ste & _SEGMENT_ENTRY_ORIGIN); | |
1168 | *ste = _SEGMENT_ENTRY_EMPTY; | |
1169 | __gmap_unshadow_pgt(sg, raddr, pgt); | |
1170 | /* Free page table */ | |
1171 | page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); | |
1172 | list_del(&page->lru); | |
1173 | page_table_free_pgste(page); | |
1174 | } | |
1175 | ||
1176 | /** | |
1177 | * __gmap_unshadow_sgt - remove all entries from a shadow segment table | |
1178 | * @sg: pointer to the shadow guest address space structure | |
1179 | * @raddr: rmap address in the shadow guest address space | |
1180 | * @sgt: pointer to the start of a shadow segment table | |
1181 | * | |
1182 | * Called with the sg->guest_table_lock | |
1183 | */ | |
1184 | static void __gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr, | |
1185 | unsigned long *sgt) | |
1186 | { | |
1187 | unsigned long asce, *pgt; | |
1188 | struct page *page; | |
1189 | int i; | |
1190 | ||
1191 | BUG_ON(!gmap_is_shadow(sg)); | |
1192 | asce = (unsigned long) sgt | _ASCE_TYPE_SEGMENT; | |
1193 | for (i = 0; i < 2048; i++, raddr += 1UL << 20) { | |
998f637c | 1194 | if (!(sgt[i] & _SEGMENT_ENTRY_ORIGIN)) |
4be130a0 MS |
1195 | continue; |
1196 | pgt = (unsigned long *)(sgt[i] & _REGION_ENTRY_ORIGIN); | |
1197 | sgt[i] = _SEGMENT_ENTRY_EMPTY; | |
1198 | __gmap_unshadow_pgt(sg, raddr, pgt); | |
1199 | /* Free page table */ | |
1200 | page = pfn_to_page(__pa(pgt) >> PAGE_SHIFT); | |
1201 | list_del(&page->lru); | |
1202 | page_table_free_pgste(page); | |
1203 | } | |
1204 | } | |
1205 | ||
1206 | /** | |
1207 | * gmap_unshadow_sgt - remove a shadow segment table from a region-3 entry | |
1208 | * @sg: pointer to the shadow guest address space structure | |
1209 | * @raddr: rmap address in the shadow guest address space | |
1210 | * | |
1211 | * Called with the shadow->guest_table_lock | |
1212 | */ | |
1213 | static void gmap_unshadow_sgt(struct gmap *sg, unsigned long raddr) | |
1214 | { | |
1215 | unsigned long r3o, *r3e, *sgt; | |
1216 | struct page *page; | |
1217 | ||
1218 | BUG_ON(!gmap_is_shadow(sg)); | |
1219 | r3e = gmap_table_walk(sg, raddr, 2); /* get region-3 pointer */ | |
998f637c | 1220 | if (!r3e || !(*r3e & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1221 | return; |
1222 | gmap_call_notifier(sg, raddr, raddr + (1UL << 31) - 1); | |
1223 | r3o = (unsigned long) (r3e - ((raddr >> 31) & 0x7ff)); | |
1224 | gmap_idte_one(r3o | _ASCE_TYPE_REGION3, raddr); | |
1225 | sgt = (unsigned long *)(*r3e & _REGION_ENTRY_ORIGIN); | |
1226 | *r3e = _REGION3_ENTRY_EMPTY; | |
1227 | __gmap_unshadow_sgt(sg, raddr, sgt); | |
1228 | /* Free segment table */ | |
1229 | page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); | |
1230 | list_del(&page->lru); | |
1231 | __free_pages(page, 2); | |
1232 | } | |
1233 | ||
1234 | /** | |
1235 | * __gmap_unshadow_r3t - remove all entries from a shadow region-3 table | |
1236 | * @sg: pointer to the shadow guest address space structure | |
1237 | * @raddr: address in the shadow guest address space | |
1238 | * @r3t: pointer to the start of a shadow region-3 table | |
1239 | * | |
1240 | * Called with the sg->guest_table_lock | |
1241 | */ | |
1242 | static void __gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr, | |
1243 | unsigned long *r3t) | |
1244 | { | |
1245 | unsigned long asce, *sgt; | |
1246 | struct page *page; | |
1247 | int i; | |
1248 | ||
1249 | BUG_ON(!gmap_is_shadow(sg)); | |
1250 | asce = (unsigned long) r3t | _ASCE_TYPE_REGION3; | |
1251 | for (i = 0; i < 2048; i++, raddr += 1UL << 31) { | |
998f637c | 1252 | if (!(r3t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1253 | continue; |
1254 | sgt = (unsigned long *)(r3t[i] & _REGION_ENTRY_ORIGIN); | |
1255 | r3t[i] = _REGION3_ENTRY_EMPTY; | |
1256 | __gmap_unshadow_sgt(sg, raddr, sgt); | |
1257 | /* Free segment table */ | |
1258 | page = pfn_to_page(__pa(sgt) >> PAGE_SHIFT); | |
1259 | list_del(&page->lru); | |
1260 | __free_pages(page, 2); | |
1261 | } | |
1262 | } | |
1263 | ||
1264 | /** | |
1265 | * gmap_unshadow_r3t - remove a shadow region-3 table from a region-2 entry | |
1266 | * @sg: pointer to the shadow guest address space structure | |
1267 | * @raddr: rmap address in the shadow guest address space | |
1268 | * | |
1269 | * Called with the sg->guest_table_lock | |
1270 | */ | |
1271 | static void gmap_unshadow_r3t(struct gmap *sg, unsigned long raddr) | |
1272 | { | |
1273 | unsigned long r2o, *r2e, *r3t; | |
1274 | struct page *page; | |
1275 | ||
1276 | BUG_ON(!gmap_is_shadow(sg)); | |
1277 | r2e = gmap_table_walk(sg, raddr, 3); /* get region-2 pointer */ | |
998f637c | 1278 | if (!r2e || !(*r2e & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1279 | return; |
1280 | gmap_call_notifier(sg, raddr, raddr + (1UL << 42) - 1); | |
1281 | r2o = (unsigned long) (r2e - ((raddr >> 42) & 0x7ff)); | |
1282 | gmap_idte_one(r2o | _ASCE_TYPE_REGION2, raddr); | |
1283 | r3t = (unsigned long *)(*r2e & _REGION_ENTRY_ORIGIN); | |
1284 | *r2e = _REGION2_ENTRY_EMPTY; | |
1285 | __gmap_unshadow_r3t(sg, raddr, r3t); | |
1286 | /* Free region 3 table */ | |
1287 | page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); | |
1288 | list_del(&page->lru); | |
1289 | __free_pages(page, 2); | |
1290 | } | |
1291 | ||
1292 | /** | |
1293 | * __gmap_unshadow_r2t - remove all entries from a shadow region-2 table | |
1294 | * @sg: pointer to the shadow guest address space structure | |
1295 | * @raddr: rmap address in the shadow guest address space | |
1296 | * @r2t: pointer to the start of a shadow region-2 table | |
1297 | * | |
1298 | * Called with the sg->guest_table_lock | |
1299 | */ | |
1300 | static void __gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr, | |
1301 | unsigned long *r2t) | |
1302 | { | |
1303 | unsigned long asce, *r3t; | |
1304 | struct page *page; | |
1305 | int i; | |
1306 | ||
1307 | BUG_ON(!gmap_is_shadow(sg)); | |
1308 | asce = (unsigned long) r2t | _ASCE_TYPE_REGION2; | |
1309 | for (i = 0; i < 2048; i++, raddr += 1UL << 42) { | |
998f637c | 1310 | if (!(r2t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1311 | continue; |
1312 | r3t = (unsigned long *)(r2t[i] & _REGION_ENTRY_ORIGIN); | |
1313 | r2t[i] = _REGION2_ENTRY_EMPTY; | |
1314 | __gmap_unshadow_r3t(sg, raddr, r3t); | |
1315 | /* Free region 3 table */ | |
1316 | page = pfn_to_page(__pa(r3t) >> PAGE_SHIFT); | |
1317 | list_del(&page->lru); | |
1318 | __free_pages(page, 2); | |
1319 | } | |
1320 | } | |
1321 | ||
1322 | /** | |
1323 | * gmap_unshadow_r2t - remove a shadow region-2 table from a region-1 entry | |
1324 | * @sg: pointer to the shadow guest address space structure | |
1325 | * @raddr: rmap address in the shadow guest address space | |
1326 | * | |
1327 | * Called with the sg->guest_table_lock | |
1328 | */ | |
1329 | static void gmap_unshadow_r2t(struct gmap *sg, unsigned long raddr) | |
1330 | { | |
1331 | unsigned long r1o, *r1e, *r2t; | |
1332 | struct page *page; | |
1333 | ||
1334 | BUG_ON(!gmap_is_shadow(sg)); | |
1335 | r1e = gmap_table_walk(sg, raddr, 4); /* get region-1 pointer */ | |
998f637c | 1336 | if (!r1e || !(*r1e & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1337 | return; |
1338 | gmap_call_notifier(sg, raddr, raddr + (1UL << 53) - 1); | |
1339 | r1o = (unsigned long) (r1e - ((raddr >> 53) & 0x7ff)); | |
1340 | gmap_idte_one(r1o | _ASCE_TYPE_REGION1, raddr); | |
1341 | r2t = (unsigned long *)(*r1e & _REGION_ENTRY_ORIGIN); | |
1342 | *r1e = _REGION1_ENTRY_EMPTY; | |
1343 | __gmap_unshadow_r2t(sg, raddr, r2t); | |
1344 | /* Free region 2 table */ | |
1345 | page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); | |
1346 | list_del(&page->lru); | |
1347 | __free_pages(page, 2); | |
1348 | } | |
1349 | ||
1350 | /** | |
1351 | * __gmap_unshadow_r1t - remove all entries from a shadow region-1 table | |
1352 | * @sg: pointer to the shadow guest address space structure | |
1353 | * @raddr: rmap address in the shadow guest address space | |
1354 | * @r1t: pointer to the start of a shadow region-1 table | |
1355 | * | |
1356 | * Called with the shadow->guest_table_lock | |
1357 | */ | |
1358 | static void __gmap_unshadow_r1t(struct gmap *sg, unsigned long raddr, | |
1359 | unsigned long *r1t) | |
1360 | { | |
1361 | unsigned long asce, *r2t; | |
1362 | struct page *page; | |
1363 | int i; | |
1364 | ||
1365 | BUG_ON(!gmap_is_shadow(sg)); | |
1366 | asce = (unsigned long) r1t | _ASCE_TYPE_REGION1; | |
1367 | for (i = 0; i < 2048; i++, raddr += 1UL << 53) { | |
998f637c | 1368 | if (!(r1t[i] & _REGION_ENTRY_ORIGIN)) |
4be130a0 MS |
1369 | continue; |
1370 | r2t = (unsigned long *)(r1t[i] & _REGION_ENTRY_ORIGIN); | |
1371 | __gmap_unshadow_r2t(sg, raddr, r2t); | |
1372 | /* Clear entry and flush translation r1t -> r2t */ | |
1373 | gmap_idte_one(asce, raddr); | |
1374 | r1t[i] = _REGION1_ENTRY_EMPTY; | |
1375 | /* Free region 2 table */ | |
1376 | page = pfn_to_page(__pa(r2t) >> PAGE_SHIFT); | |
1377 | list_del(&page->lru); | |
1378 | __free_pages(page, 2); | |
1379 | } | |
1380 | } | |
1381 | ||
1382 | /** | |
1383 | * gmap_unshadow - remove a shadow page table completely | |
1384 | * @sg: pointer to the shadow guest address space structure | |
1385 | * | |
1386 | * Called with sg->guest_table_lock | |
1387 | */ | |
1388 | static void gmap_unshadow(struct gmap *sg) | |
1389 | { | |
1390 | unsigned long *table; | |
1391 | ||
1392 | BUG_ON(!gmap_is_shadow(sg)); | |
1393 | if (sg->removed) | |
1394 | return; | |
1395 | sg->removed = 1; | |
1396 | gmap_call_notifier(sg, 0, -1UL); | |
eea3678d | 1397 | gmap_flush_tlb(sg); |
4be130a0 MS |
1398 | table = (unsigned long *)(sg->asce & _ASCE_ORIGIN); |
1399 | switch (sg->asce & _ASCE_TYPE_MASK) { | |
1400 | case _ASCE_TYPE_REGION1: | |
1401 | __gmap_unshadow_r1t(sg, 0, table); | |
1402 | break; | |
1403 | case _ASCE_TYPE_REGION2: | |
1404 | __gmap_unshadow_r2t(sg, 0, table); | |
1405 | break; | |
1406 | case _ASCE_TYPE_REGION3: | |
1407 | __gmap_unshadow_r3t(sg, 0, table); | |
1408 | break; | |
1409 | case _ASCE_TYPE_SEGMENT: | |
1410 | __gmap_unshadow_sgt(sg, 0, table); | |
1411 | break; | |
1412 | } | |
1413 | } | |
1414 | ||
1415 | /** | |
1416 | * gmap_find_shadow - find a specific asce in the list of shadow tables | |
1417 | * @parent: pointer to the parent gmap | |
1418 | * @asce: ASCE for which the shadow table is created | |
5b062bd4 | 1419 | * @edat_level: edat level to be used for the shadow translation |
4be130a0 MS |
1420 | * |
1421 | * Returns the pointer to a gmap if a shadow table with the given asce is | |
0f7f8489 DH |
1422 | * already available, ERR_PTR(-EAGAIN) if another one is just being created, |
1423 | * otherwise NULL | |
4be130a0 | 1424 | */ |
5b062bd4 DH |
1425 | static struct gmap *gmap_find_shadow(struct gmap *parent, unsigned long asce, |
1426 | int edat_level) | |
4be130a0 MS |
1427 | { |
1428 | struct gmap *sg; | |
1429 | ||
1430 | list_for_each_entry(sg, &parent->children, list) { | |
5b062bd4 DH |
1431 | if (sg->orig_asce != asce || sg->edat_level != edat_level || |
1432 | sg->removed) | |
4be130a0 | 1433 | continue; |
0f7f8489 DH |
1434 | if (!sg->initialized) |
1435 | return ERR_PTR(-EAGAIN); | |
4be130a0 MS |
1436 | atomic_inc(&sg->ref_count); |
1437 | return sg; | |
1438 | } | |
1439 | return NULL; | |
1440 | } | |
1441 | ||
5b6c963b DH |
1442 | /** |
1443 | * gmap_shadow_valid - check if a shadow guest address space matches the | |
1444 | * given properties and is still valid | |
1445 | * @sg: pointer to the shadow guest address space structure | |
1446 | * @asce: ASCE for which the shadow table is requested | |
1447 | * @edat_level: edat level to be used for the shadow translation | |
1448 | * | |
1449 | * Returns 1 if the gmap shadow is still valid and matches the given | |
1450 | * properties, the caller can continue using it. Returns 0 otherwise, the | |
1451 | * caller has to request a new shadow gmap in this case. | |
1452 | * | |
1453 | */ | |
1454 | int gmap_shadow_valid(struct gmap *sg, unsigned long asce, int edat_level) | |
1455 | { | |
1456 | if (sg->removed) | |
1457 | return 0; | |
1458 | return sg->orig_asce == asce && sg->edat_level == edat_level; | |
1459 | } | |
1460 | EXPORT_SYMBOL_GPL(gmap_shadow_valid); | |
1461 | ||
4be130a0 MS |
1462 | /** |
1463 | * gmap_shadow - create/find a shadow guest address space | |
1464 | * @parent: pointer to the parent gmap | |
1465 | * @asce: ASCE for which the shadow table is created | |
5b062bd4 | 1466 | * @edat_level: edat level to be used for the shadow translation |
4be130a0 MS |
1467 | * |
1468 | * The pages of the top level page table referred by the asce parameter | |
1469 | * will be set to read-only and marked in the PGSTEs of the kvm process. | |
1470 | * The shadow table will be removed automatically on any change to the | |
1471 | * PTE mapping for the source table. | |
1472 | * | |
0f7f8489 DH |
1473 | * Returns a guest address space structure, ERR_PTR(-ENOMEM) if out of memory, |
1474 | * ERR_PTR(-EAGAIN) if the caller has to retry and ERR_PTR(-EFAULT) if the | |
1475 | * parent gmap table could not be protected. | |
4be130a0 | 1476 | */ |
5b062bd4 DH |
1477 | struct gmap *gmap_shadow(struct gmap *parent, unsigned long asce, |
1478 | int edat_level) | |
4be130a0 MS |
1479 | { |
1480 | struct gmap *sg, *new; | |
1481 | unsigned long limit; | |
1482 | int rc; | |
1483 | ||
1484 | BUG_ON(gmap_is_shadow(parent)); | |
1485 | spin_lock(&parent->shadow_lock); | |
5b062bd4 | 1486 | sg = gmap_find_shadow(parent, asce, edat_level); |
4be130a0 MS |
1487 | spin_unlock(&parent->shadow_lock); |
1488 | if (sg) | |
1489 | return sg; | |
1490 | /* Create a new shadow gmap */ | |
1491 | limit = -1UL >> (33 - (((asce & _ASCE_TYPE_MASK) >> 2) * 11)); | |
3218f709 DH |
1492 | if (asce & _ASCE_REAL_SPACE) |
1493 | limit = -1UL; | |
4be130a0 MS |
1494 | new = gmap_alloc(limit); |
1495 | if (!new) | |
0f7f8489 | 1496 | return ERR_PTR(-ENOMEM); |
4be130a0 MS |
1497 | new->mm = parent->mm; |
1498 | new->parent = gmap_get(parent); | |
1499 | new->orig_asce = asce; | |
5b062bd4 | 1500 | new->edat_level = edat_level; |
0f7f8489 DH |
1501 | new->initialized = false; |
1502 | spin_lock(&parent->shadow_lock); | |
1503 | /* Recheck if another CPU created the same shadow */ | |
5b062bd4 | 1504 | sg = gmap_find_shadow(parent, asce, edat_level); |
0f7f8489 DH |
1505 | if (sg) { |
1506 | spin_unlock(&parent->shadow_lock); | |
1507 | gmap_free(new); | |
1508 | return sg; | |
1509 | } | |
717c0555 DH |
1510 | if (asce & _ASCE_REAL_SPACE) { |
1511 | /* only allow one real-space gmap shadow */ | |
1512 | list_for_each_entry(sg, &parent->children, list) { | |
1513 | if (sg->orig_asce & _ASCE_REAL_SPACE) { | |
1514 | spin_lock(&sg->guest_table_lock); | |
1515 | gmap_unshadow(sg); | |
1516 | spin_unlock(&sg->guest_table_lock); | |
1517 | list_del(&sg->list); | |
1518 | gmap_put(sg); | |
1519 | break; | |
1520 | } | |
1521 | } | |
1522 | } | |
0f7f8489 DH |
1523 | atomic_set(&new->ref_count, 2); |
1524 | list_add(&new->list, &parent->children); | |
3218f709 DH |
1525 | if (asce & _ASCE_REAL_SPACE) { |
1526 | /* nothing to protect, return right away */ | |
1527 | new->initialized = true; | |
1528 | spin_unlock(&parent->shadow_lock); | |
1529 | return new; | |
1530 | } | |
0f7f8489 DH |
1531 | spin_unlock(&parent->shadow_lock); |
1532 | /* protect after insertion, so it will get properly invalidated */ | |
4be130a0 MS |
1533 | down_read(&parent->mm->mmap_sem); |
1534 | rc = gmap_protect_range(parent, asce & _ASCE_ORIGIN, | |
1535 | ((asce & _ASCE_TABLE_LENGTH) + 1) * 4096, | |
1536 | PROT_READ, PGSTE_VSIE_BIT); | |
1537 | up_read(&parent->mm->mmap_sem); | |
0f7f8489 DH |
1538 | spin_lock(&parent->shadow_lock); |
1539 | new->initialized = true; | |
4be130a0 | 1540 | if (rc) { |
0f7f8489 | 1541 | list_del(&new->list); |
4be130a0 | 1542 | gmap_free(new); |
0f7f8489 DH |
1543 | new = ERR_PTR(rc); |
1544 | } | |
1545 | spin_unlock(&parent->shadow_lock); | |
1546 | return new; | |
4be130a0 MS |
1547 | } |
1548 | EXPORT_SYMBOL_GPL(gmap_shadow); | |
1549 | ||
1550 | /** | |
1551 | * gmap_shadow_r2t - create an empty shadow region 2 table | |
1552 | * @sg: pointer to the shadow guest address space structure | |
1553 | * @saddr: faulting address in the shadow gmap | |
1554 | * @r2t: parent gmap address of the region 2 table to get shadowed | |
3218f709 | 1555 | * @fake: r2t references contiguous guest memory block, not a r2t |
4be130a0 MS |
1556 | * |
1557 | * The r2t parameter specifies the address of the source table. The | |
1558 | * four pages of the source table are made read-only in the parent gmap | |
1559 | * address space. A write to the source table area @r2t will automatically | |
1560 | * remove the shadow r2 table and all of its decendents. | |
1561 | * | |
1562 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1563 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1564 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1565 | * | |
1566 | * Called with sg->mm->mmap_sem in read. | |
1567 | */ | |
3218f709 DH |
1568 | int gmap_shadow_r2t(struct gmap *sg, unsigned long saddr, unsigned long r2t, |
1569 | int fake) | |
4be130a0 MS |
1570 | { |
1571 | unsigned long raddr, origin, offset, len; | |
1572 | unsigned long *s_r2t, *table; | |
1573 | struct page *page; | |
1574 | int rc; | |
1575 | ||
1576 | BUG_ON(!gmap_is_shadow(sg)); | |
1577 | /* Allocate a shadow region second table */ | |
1578 | page = alloc_pages(GFP_KERNEL, 2); | |
1579 | if (!page) | |
1580 | return -ENOMEM; | |
1581 | page->index = r2t & _REGION_ENTRY_ORIGIN; | |
3218f709 DH |
1582 | if (fake) |
1583 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1584 | s_r2t = (unsigned long *) page_to_phys(page); |
1585 | /* Install shadow region second table */ | |
1586 | spin_lock(&sg->guest_table_lock); | |
1587 | table = gmap_table_walk(sg, saddr, 4); /* get region-1 pointer */ | |
1588 | if (!table) { | |
1589 | rc = -EAGAIN; /* Race with unshadow */ | |
1590 | goto out_free; | |
1591 | } | |
1592 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1593 | rc = 0; /* Already established */ | |
1594 | goto out_free; | |
998f637c DH |
1595 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1596 | rc = -EAGAIN; /* Race with shadow */ | |
1597 | goto out_free; | |
4be130a0 MS |
1598 | } |
1599 | crst_table_init(s_r2t, _REGION2_ENTRY_EMPTY); | |
998f637c DH |
1600 | /* mark as invalid as long as the parent table is not protected */ |
1601 | *table = (unsigned long) s_r2t | _REGION_ENTRY_LENGTH | | |
1602 | _REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1603 | if (sg->edat_level >= 1) |
1604 | *table |= (r2t & _REGION_ENTRY_PROTECT); | |
4be130a0 | 1605 | list_add(&page->lru, &sg->crst_list); |
3218f709 DH |
1606 | if (fake) { |
1607 | /* nothing to protect for fake tables */ | |
1608 | *table &= ~_REGION_ENTRY_INVALID; | |
1609 | spin_unlock(&sg->guest_table_lock); | |
1610 | return 0; | |
1611 | } | |
4be130a0 MS |
1612 | spin_unlock(&sg->guest_table_lock); |
1613 | /* Make r2t read-only in parent gmap page table */ | |
1614 | raddr = (saddr & 0xffe0000000000000UL) | _SHADOW_RMAP_REGION1; | |
1615 | origin = r2t & _REGION_ENTRY_ORIGIN; | |
1616 | offset = ((r2t & _REGION_ENTRY_OFFSET) >> 6) * 4096; | |
1617 | len = ((r2t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset; | |
1618 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); | |
998f637c DH |
1619 | spin_lock(&sg->guest_table_lock); |
1620 | if (!rc) { | |
1621 | table = gmap_table_walk(sg, saddr, 4); | |
1622 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1623 | (unsigned long) s_r2t) | |
1624 | rc = -EAGAIN; /* Race with unshadow */ | |
1625 | else | |
1626 | *table &= ~_REGION_ENTRY_INVALID; | |
1627 | } else { | |
4be130a0 | 1628 | gmap_unshadow_r2t(sg, raddr); |
4be130a0 | 1629 | } |
998f637c | 1630 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1631 | return rc; |
1632 | out_free: | |
1633 | spin_unlock(&sg->guest_table_lock); | |
1634 | __free_pages(page, 2); | |
1e133ab2 MS |
1635 | return rc; |
1636 | } | |
4be130a0 MS |
1637 | EXPORT_SYMBOL_GPL(gmap_shadow_r2t); |
1638 | ||
1639 | /** | |
1640 | * gmap_shadow_r3t - create a shadow region 3 table | |
1641 | * @sg: pointer to the shadow guest address space structure | |
1642 | * @saddr: faulting address in the shadow gmap | |
1643 | * @r3t: parent gmap address of the region 3 table to get shadowed | |
3218f709 | 1644 | * @fake: r3t references contiguous guest memory block, not a r3t |
4be130a0 MS |
1645 | * |
1646 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1647 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1648 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1649 | * | |
1650 | * Called with sg->mm->mmap_sem in read. | |
1651 | */ | |
3218f709 DH |
1652 | int gmap_shadow_r3t(struct gmap *sg, unsigned long saddr, unsigned long r3t, |
1653 | int fake) | |
4be130a0 MS |
1654 | { |
1655 | unsigned long raddr, origin, offset, len; | |
1656 | unsigned long *s_r3t, *table; | |
1657 | struct page *page; | |
1658 | int rc; | |
1659 | ||
1660 | BUG_ON(!gmap_is_shadow(sg)); | |
1661 | /* Allocate a shadow region second table */ | |
1662 | page = alloc_pages(GFP_KERNEL, 2); | |
1663 | if (!page) | |
1664 | return -ENOMEM; | |
1665 | page->index = r3t & _REGION_ENTRY_ORIGIN; | |
3218f709 DH |
1666 | if (fake) |
1667 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1668 | s_r3t = (unsigned long *) page_to_phys(page); |
1669 | /* Install shadow region second table */ | |
1670 | spin_lock(&sg->guest_table_lock); | |
1671 | table = gmap_table_walk(sg, saddr, 3); /* get region-2 pointer */ | |
1672 | if (!table) { | |
1673 | rc = -EAGAIN; /* Race with unshadow */ | |
1674 | goto out_free; | |
1675 | } | |
1676 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1677 | rc = 0; /* Already established */ | |
1678 | goto out_free; | |
998f637c DH |
1679 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1680 | rc = -EAGAIN; /* Race with shadow */ | |
4be130a0 MS |
1681 | } |
1682 | crst_table_init(s_r3t, _REGION3_ENTRY_EMPTY); | |
998f637c DH |
1683 | /* mark as invalid as long as the parent table is not protected */ |
1684 | *table = (unsigned long) s_r3t | _REGION_ENTRY_LENGTH | | |
1685 | _REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1686 | if (sg->edat_level >= 1) |
1687 | *table |= (r3t & _REGION_ENTRY_PROTECT); | |
4be130a0 | 1688 | list_add(&page->lru, &sg->crst_list); |
3218f709 DH |
1689 | if (fake) { |
1690 | /* nothing to protect for fake tables */ | |
1691 | *table &= ~_REGION_ENTRY_INVALID; | |
1692 | spin_unlock(&sg->guest_table_lock); | |
1693 | return 0; | |
1694 | } | |
4be130a0 MS |
1695 | spin_unlock(&sg->guest_table_lock); |
1696 | /* Make r3t read-only in parent gmap page table */ | |
1697 | raddr = (saddr & 0xfffffc0000000000UL) | _SHADOW_RMAP_REGION2; | |
1698 | origin = r3t & _REGION_ENTRY_ORIGIN; | |
1699 | offset = ((r3t & _REGION_ENTRY_OFFSET) >> 6) * 4096; | |
1700 | len = ((r3t & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset; | |
1701 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); | |
998f637c DH |
1702 | spin_lock(&sg->guest_table_lock); |
1703 | if (!rc) { | |
1704 | table = gmap_table_walk(sg, saddr, 3); | |
1705 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1706 | (unsigned long) s_r3t) | |
1707 | rc = -EAGAIN; /* Race with unshadow */ | |
1708 | else | |
1709 | *table &= ~_REGION_ENTRY_INVALID; | |
1710 | } else { | |
4be130a0 | 1711 | gmap_unshadow_r3t(sg, raddr); |
4be130a0 | 1712 | } |
998f637c | 1713 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1714 | return rc; |
1715 | out_free: | |
1716 | spin_unlock(&sg->guest_table_lock); | |
1717 | __free_pages(page, 2); | |
1718 | return rc; | |
1719 | } | |
1720 | EXPORT_SYMBOL_GPL(gmap_shadow_r3t); | |
1721 | ||
1722 | /** | |
1723 | * gmap_shadow_sgt - create a shadow segment table | |
1724 | * @sg: pointer to the shadow guest address space structure | |
1725 | * @saddr: faulting address in the shadow gmap | |
1726 | * @sgt: parent gmap address of the segment table to get shadowed | |
18b89809 | 1727 | * @fake: sgt references contiguous guest memory block, not a sgt |
4be130a0 MS |
1728 | * |
1729 | * Returns: 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1730 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1731 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1732 | * | |
1733 | * Called with sg->mm->mmap_sem in read. | |
1734 | */ | |
18b89809 DH |
1735 | int gmap_shadow_sgt(struct gmap *sg, unsigned long saddr, unsigned long sgt, |
1736 | int fake) | |
4be130a0 MS |
1737 | { |
1738 | unsigned long raddr, origin, offset, len; | |
1739 | unsigned long *s_sgt, *table; | |
1740 | struct page *page; | |
1741 | int rc; | |
1742 | ||
18b89809 | 1743 | BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE)); |
4be130a0 MS |
1744 | /* Allocate a shadow segment table */ |
1745 | page = alloc_pages(GFP_KERNEL, 2); | |
1746 | if (!page) | |
1747 | return -ENOMEM; | |
1748 | page->index = sgt & _REGION_ENTRY_ORIGIN; | |
18b89809 DH |
1749 | if (fake) |
1750 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1751 | s_sgt = (unsigned long *) page_to_phys(page); |
1752 | /* Install shadow region second table */ | |
1753 | spin_lock(&sg->guest_table_lock); | |
1754 | table = gmap_table_walk(sg, saddr, 2); /* get region-3 pointer */ | |
1755 | if (!table) { | |
1756 | rc = -EAGAIN; /* Race with unshadow */ | |
1757 | goto out_free; | |
1758 | } | |
1759 | if (!(*table & _REGION_ENTRY_INVALID)) { | |
1760 | rc = 0; /* Already established */ | |
1761 | goto out_free; | |
998f637c DH |
1762 | } else if (*table & _REGION_ENTRY_ORIGIN) { |
1763 | rc = -EAGAIN; /* Race with shadow */ | |
1764 | goto out_free; | |
4be130a0 MS |
1765 | } |
1766 | crst_table_init(s_sgt, _SEGMENT_ENTRY_EMPTY); | |
998f637c DH |
1767 | /* mark as invalid as long as the parent table is not protected */ |
1768 | *table = (unsigned long) s_sgt | _REGION_ENTRY_LENGTH | | |
1769 | _REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INVALID; | |
fd8d4e3a DH |
1770 | if (sg->edat_level >= 1) |
1771 | *table |= sgt & _REGION_ENTRY_PROTECT; | |
4be130a0 | 1772 | list_add(&page->lru, &sg->crst_list); |
18b89809 DH |
1773 | if (fake) { |
1774 | /* nothing to protect for fake tables */ | |
1775 | *table &= ~_REGION_ENTRY_INVALID; | |
1776 | spin_unlock(&sg->guest_table_lock); | |
1777 | return 0; | |
1778 | } | |
4be130a0 MS |
1779 | spin_unlock(&sg->guest_table_lock); |
1780 | /* Make sgt read-only in parent gmap page table */ | |
1781 | raddr = (saddr & 0xffffffff80000000UL) | _SHADOW_RMAP_REGION3; | |
1782 | origin = sgt & _REGION_ENTRY_ORIGIN; | |
1783 | offset = ((sgt & _REGION_ENTRY_OFFSET) >> 6) * 4096; | |
1784 | len = ((sgt & _REGION_ENTRY_LENGTH) + 1) * 4096 - offset; | |
1785 | rc = gmap_protect_rmap(sg, raddr, origin + offset, len, PROT_READ); | |
998f637c DH |
1786 | spin_lock(&sg->guest_table_lock); |
1787 | if (!rc) { | |
1788 | table = gmap_table_walk(sg, saddr, 2); | |
1789 | if (!table || (*table & _REGION_ENTRY_ORIGIN) != | |
1790 | (unsigned long) s_sgt) | |
1791 | rc = -EAGAIN; /* Race with unshadow */ | |
1792 | else | |
1793 | *table &= ~_REGION_ENTRY_INVALID; | |
1794 | } else { | |
4be130a0 | 1795 | gmap_unshadow_sgt(sg, raddr); |
4be130a0 | 1796 | } |
998f637c | 1797 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1798 | return rc; |
1799 | out_free: | |
1800 | spin_unlock(&sg->guest_table_lock); | |
1801 | __free_pages(page, 2); | |
1802 | return rc; | |
1803 | } | |
1804 | EXPORT_SYMBOL_GPL(gmap_shadow_sgt); | |
1805 | ||
1806 | /** | |
1807 | * gmap_shadow_lookup_pgtable - find a shadow page table | |
1808 | * @sg: pointer to the shadow guest address space structure | |
1809 | * @saddr: the address in the shadow aguest address space | |
1810 | * @pgt: parent gmap address of the page table to get shadowed | |
1811 | * @dat_protection: if the pgtable is marked as protected by dat | |
fd8d4e3a | 1812 | * @fake: pgt references contiguous guest memory block, not a pgtable |
4be130a0 MS |
1813 | * |
1814 | * Returns 0 if the shadow page table was found and -EAGAIN if the page | |
1815 | * table was not found. | |
1816 | * | |
1817 | * Called with sg->mm->mmap_sem in read. | |
1818 | */ | |
1819 | int gmap_shadow_pgt_lookup(struct gmap *sg, unsigned long saddr, | |
fd8d4e3a DH |
1820 | unsigned long *pgt, int *dat_protection, |
1821 | int *fake) | |
4be130a0 MS |
1822 | { |
1823 | unsigned long *table; | |
1824 | struct page *page; | |
1825 | int rc; | |
1826 | ||
1827 | BUG_ON(!gmap_is_shadow(sg)); | |
1828 | spin_lock(&sg->guest_table_lock); | |
1829 | table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ | |
1830 | if (table && !(*table & _SEGMENT_ENTRY_INVALID)) { | |
1831 | /* Shadow page tables are full pages (pte+pgste) */ | |
1832 | page = pfn_to_page(*table >> PAGE_SHIFT); | |
fd8d4e3a | 1833 | *pgt = page->index & ~GMAP_SHADOW_FAKE_TABLE; |
4be130a0 | 1834 | *dat_protection = !!(*table & _SEGMENT_ENTRY_PROTECT); |
fd8d4e3a | 1835 | *fake = !!(page->index & GMAP_SHADOW_FAKE_TABLE); |
4be130a0 MS |
1836 | rc = 0; |
1837 | } else { | |
1838 | rc = -EAGAIN; | |
1839 | } | |
1840 | spin_unlock(&sg->guest_table_lock); | |
1841 | return rc; | |
1842 | ||
1843 | } | |
1844 | EXPORT_SYMBOL_GPL(gmap_shadow_pgt_lookup); | |
1845 | ||
1846 | /** | |
1847 | * gmap_shadow_pgt - instantiate a shadow page table | |
1848 | * @sg: pointer to the shadow guest address space structure | |
1849 | * @saddr: faulting address in the shadow gmap | |
1850 | * @pgt: parent gmap address of the page table to get shadowed | |
fd8d4e3a | 1851 | * @fake: pgt references contiguous guest memory block, not a pgtable |
4be130a0 MS |
1852 | * |
1853 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1854 | * shadow table structure is incomplete, -ENOMEM if out of memory, | |
1855 | * -EFAULT if an address in the parent gmap could not be resolved and | |
1856 | * | |
1857 | * Called with gmap->mm->mmap_sem in read | |
1858 | */ | |
fd8d4e3a DH |
1859 | int gmap_shadow_pgt(struct gmap *sg, unsigned long saddr, unsigned long pgt, |
1860 | int fake) | |
4be130a0 MS |
1861 | { |
1862 | unsigned long raddr, origin; | |
1863 | unsigned long *s_pgt, *table; | |
1864 | struct page *page; | |
1865 | int rc; | |
1866 | ||
fd8d4e3a | 1867 | BUG_ON(!gmap_is_shadow(sg) || (pgt & _SEGMENT_ENTRY_LARGE)); |
4be130a0 MS |
1868 | /* Allocate a shadow page table */ |
1869 | page = page_table_alloc_pgste(sg->mm); | |
1870 | if (!page) | |
1871 | return -ENOMEM; | |
1872 | page->index = pgt & _SEGMENT_ENTRY_ORIGIN; | |
fd8d4e3a DH |
1873 | if (fake) |
1874 | page->index |= GMAP_SHADOW_FAKE_TABLE; | |
4be130a0 MS |
1875 | s_pgt = (unsigned long *) page_to_phys(page); |
1876 | /* Install shadow page table */ | |
1877 | spin_lock(&sg->guest_table_lock); | |
1878 | table = gmap_table_walk(sg, saddr, 1); /* get segment pointer */ | |
1879 | if (!table) { | |
1880 | rc = -EAGAIN; /* Race with unshadow */ | |
1881 | goto out_free; | |
1882 | } | |
1883 | if (!(*table & _SEGMENT_ENTRY_INVALID)) { | |
1884 | rc = 0; /* Already established */ | |
1885 | goto out_free; | |
998f637c DH |
1886 | } else if (*table & _SEGMENT_ENTRY_ORIGIN) { |
1887 | rc = -EAGAIN; /* Race with shadow */ | |
1888 | goto out_free; | |
4be130a0 | 1889 | } |
998f637c | 1890 | /* mark as invalid as long as the parent table is not protected */ |
4be130a0 | 1891 | *table = (unsigned long) s_pgt | _SEGMENT_ENTRY | |
998f637c | 1892 | (pgt & _SEGMENT_ENTRY_PROTECT) | _SEGMENT_ENTRY_INVALID; |
4be130a0 | 1893 | list_add(&page->lru, &sg->pt_list); |
fd8d4e3a DH |
1894 | if (fake) { |
1895 | /* nothing to protect for fake tables */ | |
1896 | *table &= ~_SEGMENT_ENTRY_INVALID; | |
1897 | spin_unlock(&sg->guest_table_lock); | |
1898 | return 0; | |
1899 | } | |
4be130a0 MS |
1900 | spin_unlock(&sg->guest_table_lock); |
1901 | /* Make pgt read-only in parent gmap page table (not the pgste) */ | |
1902 | raddr = (saddr & 0xfffffffffff00000UL) | _SHADOW_RMAP_SEGMENT; | |
1903 | origin = pgt & _SEGMENT_ENTRY_ORIGIN & PAGE_MASK; | |
1904 | rc = gmap_protect_rmap(sg, raddr, origin, PAGE_SIZE, PROT_READ); | |
998f637c DH |
1905 | spin_lock(&sg->guest_table_lock); |
1906 | if (!rc) { | |
1907 | table = gmap_table_walk(sg, saddr, 1); | |
1908 | if (!table || (*table & _SEGMENT_ENTRY_ORIGIN) != | |
1909 | (unsigned long) s_pgt) | |
1910 | rc = -EAGAIN; /* Race with unshadow */ | |
1911 | else | |
1912 | *table &= ~_SEGMENT_ENTRY_INVALID; | |
1913 | } else { | |
4be130a0 | 1914 | gmap_unshadow_pgt(sg, raddr); |
4be130a0 | 1915 | } |
998f637c | 1916 | spin_unlock(&sg->guest_table_lock); |
4be130a0 MS |
1917 | return rc; |
1918 | out_free: | |
1919 | spin_unlock(&sg->guest_table_lock); | |
1920 | page_table_free_pgste(page); | |
1921 | return rc; | |
1922 | ||
1923 | } | |
1924 | EXPORT_SYMBOL_GPL(gmap_shadow_pgt); | |
1925 | ||
1926 | /** | |
1927 | * gmap_shadow_page - create a shadow page mapping | |
1928 | * @sg: pointer to the shadow guest address space structure | |
1929 | * @saddr: faulting address in the shadow gmap | |
a9d23e71 | 1930 | * @pte: pte in parent gmap address space to get shadowed |
4be130a0 MS |
1931 | * |
1932 | * Returns 0 if successfully shadowed or already shadowed, -EAGAIN if the | |
1933 | * shadow table structure is incomplete, -ENOMEM if out of memory and | |
1934 | * -EFAULT if an address in the parent gmap could not be resolved. | |
1935 | * | |
1936 | * Called with sg->mm->mmap_sem in read. | |
1937 | */ | |
a9d23e71 | 1938 | int gmap_shadow_page(struct gmap *sg, unsigned long saddr, pte_t pte) |
4be130a0 MS |
1939 | { |
1940 | struct gmap *parent; | |
1941 | struct gmap_rmap *rmap; | |
a9d23e71 | 1942 | unsigned long vmaddr, paddr; |
4be130a0 MS |
1943 | spinlock_t *ptl; |
1944 | pte_t *sptep, *tptep; | |
01f71917 | 1945 | int prot; |
4be130a0 MS |
1946 | int rc; |
1947 | ||
1948 | BUG_ON(!gmap_is_shadow(sg)); | |
1949 | parent = sg->parent; | |
01f71917 | 1950 | prot = (pte_val(pte) & _PAGE_PROTECT) ? PROT_READ : PROT_WRITE; |
4be130a0 MS |
1951 | |
1952 | rmap = kzalloc(sizeof(*rmap), GFP_KERNEL); | |
1953 | if (!rmap) | |
1954 | return -ENOMEM; | |
1955 | rmap->raddr = (saddr & PAGE_MASK) | _SHADOW_RMAP_PGTABLE; | |
1956 | ||
1957 | while (1) { | |
a9d23e71 | 1958 | paddr = pte_val(pte) & PAGE_MASK; |
4be130a0 MS |
1959 | vmaddr = __gmap_translate(parent, paddr); |
1960 | if (IS_ERR_VALUE(vmaddr)) { | |
1961 | rc = vmaddr; | |
1962 | break; | |
1963 | } | |
1964 | rc = radix_tree_preload(GFP_KERNEL); | |
1965 | if (rc) | |
1966 | break; | |
1967 | rc = -EAGAIN; | |
1968 | sptep = gmap_pte_op_walk(parent, paddr, &ptl); | |
1969 | if (sptep) { | |
1970 | spin_lock(&sg->guest_table_lock); | |
1971 | /* Get page table pointer */ | |
1972 | tptep = (pte_t *) gmap_table_walk(sg, saddr, 0); | |
1973 | if (!tptep) { | |
1974 | spin_unlock(&sg->guest_table_lock); | |
1975 | gmap_pte_op_end(ptl); | |
1976 | radix_tree_preload_end(); | |
1977 | break; | |
1978 | } | |
a9d23e71 | 1979 | rc = ptep_shadow_pte(sg->mm, saddr, sptep, tptep, pte); |
4be130a0 MS |
1980 | if (rc > 0) { |
1981 | /* Success and a new mapping */ | |
1982 | gmap_insert_rmap(sg, vmaddr, rmap); | |
1983 | rmap = NULL; | |
1984 | rc = 0; | |
1985 | } | |
1986 | gmap_pte_op_end(ptl); | |
1987 | spin_unlock(&sg->guest_table_lock); | |
1988 | } | |
1989 | radix_tree_preload_end(); | |
1990 | if (!rc) | |
1991 | break; | |
01f71917 | 1992 | rc = gmap_pte_op_fixup(parent, paddr, vmaddr, prot); |
4be130a0 MS |
1993 | if (rc) |
1994 | break; | |
1995 | } | |
1996 | kfree(rmap); | |
1997 | return rc; | |
1998 | } | |
1999 | EXPORT_SYMBOL_GPL(gmap_shadow_page); | |
2000 | ||
2001 | /** | |
2002 | * gmap_shadow_notify - handle notifications for shadow gmap | |
2003 | * | |
2004 | * Called with sg->parent->shadow_lock. | |
2005 | */ | |
2006 | static void gmap_shadow_notify(struct gmap *sg, unsigned long vmaddr, | |
2007 | unsigned long offset, pte_t *pte) | |
2008 | { | |
2009 | struct gmap_rmap *rmap, *rnext, *head; | |
2010 | unsigned long gaddr, start, end, bits, raddr; | |
2011 | unsigned long *table; | |
2012 | ||
2013 | BUG_ON(!gmap_is_shadow(sg)); | |
2014 | spin_lock(&sg->parent->guest_table_lock); | |
2015 | table = radix_tree_lookup(&sg->parent->host_to_guest, | |
2016 | vmaddr >> PMD_SHIFT); | |
2017 | gaddr = table ? __gmap_segment_gaddr(table) + offset : 0; | |
2018 | spin_unlock(&sg->parent->guest_table_lock); | |
2019 | if (!table) | |
2020 | return; | |
2021 | ||
2022 | spin_lock(&sg->guest_table_lock); | |
2023 | if (sg->removed) { | |
2024 | spin_unlock(&sg->guest_table_lock); | |
2025 | return; | |
2026 | } | |
2027 | /* Check for top level table */ | |
2028 | start = sg->orig_asce & _ASCE_ORIGIN; | |
2029 | end = start + ((sg->orig_asce & _ASCE_TABLE_LENGTH) + 1) * 4096; | |
3218f709 DH |
2030 | if (!(sg->orig_asce & _ASCE_REAL_SPACE) && gaddr >= start && |
2031 | gaddr < end) { | |
4be130a0 MS |
2032 | /* The complete shadow table has to go */ |
2033 | gmap_unshadow(sg); | |
2034 | spin_unlock(&sg->guest_table_lock); | |
2035 | list_del(&sg->list); | |
2036 | gmap_put(sg); | |
2037 | return; | |
2038 | } | |
2039 | /* Remove the page table tree from on specific entry */ | |
2040 | head = radix_tree_delete(&sg->host_to_rmap, vmaddr >> 12); | |
2041 | gmap_for_each_rmap_safe(rmap, rnext, head) { | |
2042 | bits = rmap->raddr & _SHADOW_RMAP_MASK; | |
2043 | raddr = rmap->raddr ^ bits; | |
2044 | switch (bits) { | |
2045 | case _SHADOW_RMAP_REGION1: | |
2046 | gmap_unshadow_r2t(sg, raddr); | |
2047 | break; | |
2048 | case _SHADOW_RMAP_REGION2: | |
2049 | gmap_unshadow_r3t(sg, raddr); | |
2050 | break; | |
2051 | case _SHADOW_RMAP_REGION3: | |
2052 | gmap_unshadow_sgt(sg, raddr); | |
2053 | break; | |
2054 | case _SHADOW_RMAP_SEGMENT: | |
2055 | gmap_unshadow_pgt(sg, raddr); | |
2056 | break; | |
2057 | case _SHADOW_RMAP_PGTABLE: | |
2058 | gmap_unshadow_page(sg, raddr); | |
2059 | break; | |
2060 | } | |
2061 | kfree(rmap); | |
2062 | } | |
2063 | spin_unlock(&sg->guest_table_lock); | |
2064 | } | |
1e133ab2 MS |
2065 | |
2066 | /** | |
2067 | * ptep_notify - call all invalidation callbacks for a specific pte. | |
2068 | * @mm: pointer to the process mm_struct | |
2069 | * @addr: virtual address in the process address space | |
2070 | * @pte: pointer to the page table entry | |
4be130a0 | 2071 | * @bits: bits from the pgste that caused the notify call |
1e133ab2 MS |
2072 | * |
2073 | * This function is assumed to be called with the page table lock held | |
2074 | * for the pte to notify. | |
2075 | */ | |
4be130a0 MS |
2076 | void ptep_notify(struct mm_struct *mm, unsigned long vmaddr, |
2077 | pte_t *pte, unsigned long bits) | |
1e133ab2 MS |
2078 | { |
2079 | unsigned long offset, gaddr; | |
2080 | unsigned long *table; | |
4be130a0 | 2081 | struct gmap *gmap, *sg, *next; |
1e133ab2 MS |
2082 | |
2083 | offset = ((unsigned long) pte) & (255 * sizeof(pte_t)); | |
2084 | offset = offset * (4096 / sizeof(pte_t)); | |
8ecb1a59 MS |
2085 | rcu_read_lock(); |
2086 | list_for_each_entry_rcu(gmap, &mm->context.gmap_list, list) { | |
4be130a0 MS |
2087 | if (!list_empty(&gmap->children) && (bits & PGSTE_VSIE_BIT)) { |
2088 | spin_lock(&gmap->shadow_lock); | |
2089 | list_for_each_entry_safe(sg, next, | |
2090 | &gmap->children, list) | |
2091 | gmap_shadow_notify(sg, vmaddr, offset, pte); | |
2092 | spin_unlock(&gmap->shadow_lock); | |
2093 | } | |
2094 | if (!(bits & PGSTE_IN_BIT)) | |
2095 | continue; | |
8ecb1a59 | 2096 | spin_lock(&gmap->guest_table_lock); |
1e133ab2 MS |
2097 | table = radix_tree_lookup(&gmap->host_to_guest, |
2098 | vmaddr >> PMD_SHIFT); | |
8ecb1a59 MS |
2099 | if (table) |
2100 | gaddr = __gmap_segment_gaddr(table) + offset; | |
2101 | spin_unlock(&gmap->guest_table_lock); | |
2102 | if (table) | |
2103 | gmap_call_notifier(gmap, gaddr, gaddr + PAGE_SIZE - 1); | |
1e133ab2 | 2104 | } |
8ecb1a59 | 2105 | rcu_read_unlock(); |
1e133ab2 MS |
2106 | } |
2107 | EXPORT_SYMBOL_GPL(ptep_notify); | |
2108 | ||
2109 | static inline void thp_split_mm(struct mm_struct *mm) | |
2110 | { | |
2111 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | |
2112 | struct vm_area_struct *vma; | |
2113 | unsigned long addr; | |
2114 | ||
2115 | for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) { | |
2116 | for (addr = vma->vm_start; | |
2117 | addr < vma->vm_end; | |
2118 | addr += PAGE_SIZE) | |
2119 | follow_page(vma, addr, FOLL_SPLIT); | |
2120 | vma->vm_flags &= ~VM_HUGEPAGE; | |
2121 | vma->vm_flags |= VM_NOHUGEPAGE; | |
2122 | } | |
2123 | mm->def_flags |= VM_NOHUGEPAGE; | |
2124 | #endif | |
2125 | } | |
2126 | ||
2127 | /* | |
2128 | * switch on pgstes for its userspace process (for kvm) | |
2129 | */ | |
2130 | int s390_enable_sie(void) | |
2131 | { | |
2132 | struct mm_struct *mm = current->mm; | |
2133 | ||
2134 | /* Do we have pgstes? if yes, we are done */ | |
2135 | if (mm_has_pgste(mm)) | |
2136 | return 0; | |
2137 | /* Fail if the page tables are 2K */ | |
2138 | if (!mm_alloc_pgste(mm)) | |
2139 | return -EINVAL; | |
2140 | down_write(&mm->mmap_sem); | |
2141 | mm->context.has_pgste = 1; | |
2142 | /* split thp mappings and disable thp for future mappings */ | |
2143 | thp_split_mm(mm); | |
2144 | up_write(&mm->mmap_sem); | |
2145 | return 0; | |
2146 | } | |
2147 | EXPORT_SYMBOL_GPL(s390_enable_sie); | |
2148 | ||
2149 | /* | |
2150 | * Enable storage key handling from now on and initialize the storage | |
2151 | * keys with the default key. | |
2152 | */ | |
2153 | static int __s390_enable_skey(pte_t *pte, unsigned long addr, | |
2154 | unsigned long next, struct mm_walk *walk) | |
2155 | { | |
2156 | /* | |
2157 | * Remove all zero page mappings, | |
2158 | * after establishing a policy to forbid zero page mappings | |
2159 | * following faults for that page will get fresh anonymous pages | |
2160 | */ | |
2161 | if (is_zero_pfn(pte_pfn(*pte))) | |
2162 | ptep_xchg_direct(walk->mm, addr, pte, __pte(_PAGE_INVALID)); | |
2163 | /* Clear storage key */ | |
2164 | ptep_zap_key(walk->mm, addr, pte); | |
2165 | return 0; | |
2166 | } | |
2167 | ||
2168 | int s390_enable_skey(void) | |
2169 | { | |
2170 | struct mm_walk walk = { .pte_entry = __s390_enable_skey }; | |
2171 | struct mm_struct *mm = current->mm; | |
2172 | struct vm_area_struct *vma; | |
2173 | int rc = 0; | |
2174 | ||
2175 | down_write(&mm->mmap_sem); | |
2176 | if (mm_use_skey(mm)) | |
2177 | goto out_up; | |
2178 | ||
2179 | mm->context.use_skey = 1; | |
2180 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
2181 | if (ksm_madvise(vma, vma->vm_start, vma->vm_end, | |
2182 | MADV_UNMERGEABLE, &vma->vm_flags)) { | |
2183 | mm->context.use_skey = 0; | |
2184 | rc = -ENOMEM; | |
2185 | goto out_up; | |
2186 | } | |
2187 | } | |
2188 | mm->def_flags &= ~VM_MERGEABLE; | |
2189 | ||
2190 | walk.mm = mm; | |
2191 | walk_page_range(0, TASK_SIZE, &walk); | |
2192 | ||
2193 | out_up: | |
2194 | up_write(&mm->mmap_sem); | |
2195 | return rc; | |
2196 | } | |
2197 | EXPORT_SYMBOL_GPL(s390_enable_skey); | |
2198 | ||
2199 | /* | |
2200 | * Reset CMMA state, make all pages stable again. | |
2201 | */ | |
2202 | static int __s390_reset_cmma(pte_t *pte, unsigned long addr, | |
2203 | unsigned long next, struct mm_walk *walk) | |
2204 | { | |
2205 | ptep_zap_unused(walk->mm, addr, pte, 1); | |
2206 | return 0; | |
2207 | } | |
2208 | ||
2209 | void s390_reset_cmma(struct mm_struct *mm) | |
2210 | { | |
2211 | struct mm_walk walk = { .pte_entry = __s390_reset_cmma }; | |
2212 | ||
2213 | down_write(&mm->mmap_sem); | |
2214 | walk.mm = mm; | |
2215 | walk_page_range(0, TASK_SIZE, &walk); | |
2216 | up_write(&mm->mmap_sem); | |
2217 | } | |
2218 | EXPORT_SYMBOL_GPL(s390_reset_cmma); |