Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2001 Sistina Software (UK) Limited. | |
d5816876 | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
8 | #include "dm.h" | |
9 | ||
10 | #include <linux/module.h> | |
11 | #include <linux/vmalloc.h> | |
12 | #include <linux/blkdev.h> | |
13 | #include <linux/namei.h> | |
14 | #include <linux/ctype.h> | |
e7d2860b | 15 | #include <linux/string.h> |
1da177e4 LT |
16 | #include <linux/slab.h> |
17 | #include <linux/interrupt.h> | |
48c9c27b | 18 | #include <linux/mutex.h> |
d5816876 | 19 | #include <linux/delay.h> |
60063497 | 20 | #include <linux/atomic.h> |
1da177e4 | 21 | |
72d94861 AK |
22 | #define DM_MSG_PREFIX "table" |
23 | ||
1da177e4 LT |
24 | #define MAX_DEPTH 16 |
25 | #define NODE_SIZE L1_CACHE_BYTES | |
26 | #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t)) | |
27 | #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1) | |
28 | ||
d5816876 MP |
29 | /* |
30 | * The table has always exactly one reference from either mapped_device->map | |
31 | * or hash_cell->new_map. This reference is not counted in table->holders. | |
32 | * A pair of dm_create_table/dm_destroy_table functions is used for table | |
33 | * creation/destruction. | |
34 | * | |
35 | * Temporary references from the other code increase table->holders. A pair | |
36 | * of dm_table_get/dm_table_put functions is used to manipulate it. | |
37 | * | |
38 | * When the table is about to be destroyed, we wait for table->holders to | |
39 | * drop to zero. | |
40 | */ | |
41 | ||
1da177e4 | 42 | struct dm_table { |
1134e5ae | 43 | struct mapped_device *md; |
1da177e4 | 44 | atomic_t holders; |
e6ee8c0b | 45 | unsigned type; |
1da177e4 LT |
46 | |
47 | /* btree table */ | |
48 | unsigned int depth; | |
49 | unsigned int counts[MAX_DEPTH]; /* in nodes */ | |
50 | sector_t *index[MAX_DEPTH]; | |
51 | ||
52 | unsigned int num_targets; | |
53 | unsigned int num_allocated; | |
54 | sector_t *highs; | |
55 | struct dm_target *targets; | |
56 | ||
a91a2785 | 57 | unsigned integrity_supported:1; |
5ae89a87 | 58 | |
1da177e4 LT |
59 | /* |
60 | * Indicates the rw permissions for the new logical | |
61 | * device. This should be a combination of FMODE_READ | |
62 | * and FMODE_WRITE. | |
63 | */ | |
aeb5d727 | 64 | fmode_t mode; |
1da177e4 LT |
65 | |
66 | /* a list of devices used by this table */ | |
67 | struct list_head devices; | |
68 | ||
1da177e4 LT |
69 | /* events get handed up using this callback */ |
70 | void (*event_fn)(void *); | |
71 | void *event_context; | |
e6ee8c0b KU |
72 | |
73 | struct dm_md_mempools *mempools; | |
9d357b07 N |
74 | |
75 | struct list_head target_callbacks; | |
1da177e4 LT |
76 | }; |
77 | ||
78 | /* | |
79 | * Similar to ceiling(log_size(n)) | |
80 | */ | |
81 | static unsigned int int_log(unsigned int n, unsigned int base) | |
82 | { | |
83 | int result = 0; | |
84 | ||
85 | while (n > 1) { | |
86 | n = dm_div_up(n, base); | |
87 | result++; | |
88 | } | |
89 | ||
90 | return result; | |
91 | } | |
92 | ||
1da177e4 LT |
93 | /* |
94 | * Calculate the index of the child node of the n'th node k'th key. | |
95 | */ | |
96 | static inline unsigned int get_child(unsigned int n, unsigned int k) | |
97 | { | |
98 | return (n * CHILDREN_PER_NODE) + k; | |
99 | } | |
100 | ||
101 | /* | |
102 | * Return the n'th node of level l from table t. | |
103 | */ | |
104 | static inline sector_t *get_node(struct dm_table *t, | |
105 | unsigned int l, unsigned int n) | |
106 | { | |
107 | return t->index[l] + (n * KEYS_PER_NODE); | |
108 | } | |
109 | ||
110 | /* | |
111 | * Return the highest key that you could lookup from the n'th | |
112 | * node on level l of the btree. | |
113 | */ | |
114 | static sector_t high(struct dm_table *t, unsigned int l, unsigned int n) | |
115 | { | |
116 | for (; l < t->depth - 1; l++) | |
117 | n = get_child(n, CHILDREN_PER_NODE - 1); | |
118 | ||
119 | if (n >= t->counts[l]) | |
120 | return (sector_t) - 1; | |
121 | ||
122 | return get_node(t, l, n)[KEYS_PER_NODE - 1]; | |
123 | } | |
124 | ||
125 | /* | |
126 | * Fills in a level of the btree based on the highs of the level | |
127 | * below it. | |
128 | */ | |
129 | static int setup_btree_index(unsigned int l, struct dm_table *t) | |
130 | { | |
131 | unsigned int n, k; | |
132 | sector_t *node; | |
133 | ||
134 | for (n = 0U; n < t->counts[l]; n++) { | |
135 | node = get_node(t, l, n); | |
136 | ||
137 | for (k = 0U; k < KEYS_PER_NODE; k++) | |
138 | node[k] = high(t, l + 1, get_child(n, k)); | |
139 | } | |
140 | ||
141 | return 0; | |
142 | } | |
143 | ||
144 | void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size) | |
145 | { | |
146 | unsigned long size; | |
147 | void *addr; | |
148 | ||
149 | /* | |
150 | * Check that we're not going to overflow. | |
151 | */ | |
152 | if (nmemb > (ULONG_MAX / elem_size)) | |
153 | return NULL; | |
154 | ||
155 | size = nmemb * elem_size; | |
e29e65aa | 156 | addr = vzalloc(size); |
1da177e4 LT |
157 | |
158 | return addr; | |
159 | } | |
08649012 | 160 | EXPORT_SYMBOL(dm_vcalloc); |
1da177e4 LT |
161 | |
162 | /* | |
163 | * highs, and targets are managed as dynamic arrays during a | |
164 | * table load. | |
165 | */ | |
166 | static int alloc_targets(struct dm_table *t, unsigned int num) | |
167 | { | |
168 | sector_t *n_highs; | |
169 | struct dm_target *n_targets; | |
170 | int n = t->num_targets; | |
171 | ||
172 | /* | |
173 | * Allocate both the target array and offset array at once. | |
512875bd JN |
174 | * Append an empty entry to catch sectors beyond the end of |
175 | * the device. | |
1da177e4 | 176 | */ |
512875bd | 177 | n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) + |
1da177e4 LT |
178 | sizeof(sector_t)); |
179 | if (!n_highs) | |
180 | return -ENOMEM; | |
181 | ||
182 | n_targets = (struct dm_target *) (n_highs + num); | |
183 | ||
184 | if (n) { | |
185 | memcpy(n_highs, t->highs, sizeof(*n_highs) * n); | |
186 | memcpy(n_targets, t->targets, sizeof(*n_targets) * n); | |
187 | } | |
188 | ||
189 | memset(n_highs + n, -1, sizeof(*n_highs) * (num - n)); | |
190 | vfree(t->highs); | |
191 | ||
192 | t->num_allocated = num; | |
193 | t->highs = n_highs; | |
194 | t->targets = n_targets; | |
195 | ||
196 | return 0; | |
197 | } | |
198 | ||
aeb5d727 | 199 | int dm_table_create(struct dm_table **result, fmode_t mode, |
1134e5ae | 200 | unsigned num_targets, struct mapped_device *md) |
1da177e4 | 201 | { |
094262db | 202 | struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL); |
1da177e4 LT |
203 | |
204 | if (!t) | |
205 | return -ENOMEM; | |
206 | ||
1da177e4 | 207 | INIT_LIST_HEAD(&t->devices); |
9d357b07 | 208 | INIT_LIST_HEAD(&t->target_callbacks); |
d5816876 | 209 | atomic_set(&t->holders, 0); |
1da177e4 LT |
210 | |
211 | if (!num_targets) | |
212 | num_targets = KEYS_PER_NODE; | |
213 | ||
214 | num_targets = dm_round_up(num_targets, KEYS_PER_NODE); | |
215 | ||
216 | if (alloc_targets(t, num_targets)) { | |
217 | kfree(t); | |
218 | t = NULL; | |
219 | return -ENOMEM; | |
220 | } | |
221 | ||
222 | t->mode = mode; | |
1134e5ae | 223 | t->md = md; |
1da177e4 LT |
224 | *result = t; |
225 | return 0; | |
226 | } | |
227 | ||
228 | static void free_devices(struct list_head *devices) | |
229 | { | |
230 | struct list_head *tmp, *next; | |
231 | ||
afb24528 | 232 | list_for_each_safe(tmp, next, devices) { |
82b1519b MP |
233 | struct dm_dev_internal *dd = |
234 | list_entry(tmp, struct dm_dev_internal, list); | |
1b6da754 JB |
235 | DMWARN("dm_table_destroy: dm_put_device call missing for %s", |
236 | dd->dm_dev.name); | |
1da177e4 LT |
237 | kfree(dd); |
238 | } | |
239 | } | |
240 | ||
d5816876 | 241 | void dm_table_destroy(struct dm_table *t) |
1da177e4 LT |
242 | { |
243 | unsigned int i; | |
244 | ||
a7940155 AK |
245 | if (!t) |
246 | return; | |
247 | ||
d5816876 MP |
248 | while (atomic_read(&t->holders)) |
249 | msleep(1); | |
250 | smp_mb(); | |
251 | ||
26803b9f | 252 | /* free the indexes */ |
1da177e4 LT |
253 | if (t->depth >= 2) |
254 | vfree(t->index[t->depth - 2]); | |
255 | ||
256 | /* free the targets */ | |
257 | for (i = 0; i < t->num_targets; i++) { | |
258 | struct dm_target *tgt = t->targets + i; | |
259 | ||
260 | if (tgt->type->dtr) | |
261 | tgt->type->dtr(tgt); | |
262 | ||
263 | dm_put_target_type(tgt->type); | |
264 | } | |
265 | ||
266 | vfree(t->highs); | |
267 | ||
268 | /* free the device list */ | |
1b6da754 | 269 | if (t->devices.next != &t->devices) |
1da177e4 | 270 | free_devices(&t->devices); |
1da177e4 | 271 | |
e6ee8c0b KU |
272 | dm_free_md_mempools(t->mempools); |
273 | ||
1da177e4 LT |
274 | kfree(t); |
275 | } | |
276 | ||
277 | void dm_table_get(struct dm_table *t) | |
278 | { | |
279 | atomic_inc(&t->holders); | |
280 | } | |
08649012 | 281 | EXPORT_SYMBOL(dm_table_get); |
1da177e4 LT |
282 | |
283 | void dm_table_put(struct dm_table *t) | |
284 | { | |
285 | if (!t) | |
286 | return; | |
287 | ||
d5816876 MP |
288 | smp_mb__before_atomic_dec(); |
289 | atomic_dec(&t->holders); | |
1da177e4 | 290 | } |
08649012 | 291 | EXPORT_SYMBOL(dm_table_put); |
1da177e4 LT |
292 | |
293 | /* | |
294 | * Checks to see if we need to extend highs or targets. | |
295 | */ | |
296 | static inline int check_space(struct dm_table *t) | |
297 | { | |
298 | if (t->num_targets >= t->num_allocated) | |
299 | return alloc_targets(t, t->num_allocated * 2); | |
300 | ||
301 | return 0; | |
302 | } | |
303 | ||
1da177e4 LT |
304 | /* |
305 | * See if we've already got a device in the list. | |
306 | */ | |
82b1519b | 307 | static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev) |
1da177e4 | 308 | { |
82b1519b | 309 | struct dm_dev_internal *dd; |
1da177e4 LT |
310 | |
311 | list_for_each_entry (dd, l, list) | |
82b1519b | 312 | if (dd->dm_dev.bdev->bd_dev == dev) |
1da177e4 LT |
313 | return dd; |
314 | ||
315 | return NULL; | |
316 | } | |
317 | ||
318 | /* | |
319 | * Open a device so we can use it as a map destination. | |
320 | */ | |
82b1519b MP |
321 | static int open_dev(struct dm_dev_internal *d, dev_t dev, |
322 | struct mapped_device *md) | |
1da177e4 LT |
323 | { |
324 | static char *_claim_ptr = "I belong to device-mapper"; | |
325 | struct block_device *bdev; | |
326 | ||
327 | int r; | |
328 | ||
82b1519b | 329 | BUG_ON(d->dm_dev.bdev); |
1da177e4 | 330 | |
d4d77629 | 331 | bdev = blkdev_get_by_dev(dev, d->dm_dev.mode | FMODE_EXCL, _claim_ptr); |
1da177e4 LT |
332 | if (IS_ERR(bdev)) |
333 | return PTR_ERR(bdev); | |
e09b457b | 334 | |
e09b457b TH |
335 | r = bd_link_disk_holder(bdev, dm_disk(md)); |
336 | if (r) { | |
e525fd89 | 337 | blkdev_put(bdev, d->dm_dev.mode | FMODE_EXCL); |
e09b457b TH |
338 | return r; |
339 | } | |
340 | ||
341 | d->dm_dev.bdev = bdev; | |
342 | return 0; | |
1da177e4 LT |
343 | } |
344 | ||
345 | /* | |
346 | * Close a device that we've been using. | |
347 | */ | |
82b1519b | 348 | static void close_dev(struct dm_dev_internal *d, struct mapped_device *md) |
1da177e4 | 349 | { |
82b1519b | 350 | if (!d->dm_dev.bdev) |
1da177e4 LT |
351 | return; |
352 | ||
49731baa | 353 | bd_unlink_disk_holder(d->dm_dev.bdev, dm_disk(md)); |
e525fd89 | 354 | blkdev_put(d->dm_dev.bdev, d->dm_dev.mode | FMODE_EXCL); |
82b1519b | 355 | d->dm_dev.bdev = NULL; |
1da177e4 LT |
356 | } |
357 | ||
358 | /* | |
f6a1ed10 | 359 | * If possible, this checks an area of a destination device is invalid. |
1da177e4 | 360 | */ |
f6a1ed10 MP |
361 | static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev, |
362 | sector_t start, sector_t len, void *data) | |
1da177e4 | 363 | { |
f4808ca9 | 364 | struct request_queue *q; |
754c5fc7 MS |
365 | struct queue_limits *limits = data; |
366 | struct block_device *bdev = dev->bdev; | |
367 | sector_t dev_size = | |
368 | i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; | |
02acc3a4 | 369 | unsigned short logical_block_size_sectors = |
754c5fc7 | 370 | limits->logical_block_size >> SECTOR_SHIFT; |
02acc3a4 | 371 | char b[BDEVNAME_SIZE]; |
2cd54d9b | 372 | |
f4808ca9 MB |
373 | /* |
374 | * Some devices exist without request functions, | |
375 | * such as loop devices not yet bound to backing files. | |
376 | * Forbid the use of such devices. | |
377 | */ | |
378 | q = bdev_get_queue(bdev); | |
379 | if (!q || !q->make_request_fn) { | |
380 | DMWARN("%s: %s is not yet initialised: " | |
381 | "start=%llu, len=%llu, dev_size=%llu", | |
382 | dm_device_name(ti->table->md), bdevname(bdev, b), | |
383 | (unsigned long long)start, | |
384 | (unsigned long long)len, | |
385 | (unsigned long long)dev_size); | |
386 | return 1; | |
387 | } | |
388 | ||
2cd54d9b | 389 | if (!dev_size) |
f6a1ed10 | 390 | return 0; |
2cd54d9b | 391 | |
5dea271b | 392 | if ((start >= dev_size) || (start + len > dev_size)) { |
a963a956 MS |
393 | DMWARN("%s: %s too small for target: " |
394 | "start=%llu, len=%llu, dev_size=%llu", | |
395 | dm_device_name(ti->table->md), bdevname(bdev, b), | |
396 | (unsigned long long)start, | |
397 | (unsigned long long)len, | |
398 | (unsigned long long)dev_size); | |
f6a1ed10 | 399 | return 1; |
02acc3a4 MS |
400 | } |
401 | ||
402 | if (logical_block_size_sectors <= 1) | |
f6a1ed10 | 403 | return 0; |
02acc3a4 MS |
404 | |
405 | if (start & (logical_block_size_sectors - 1)) { | |
406 | DMWARN("%s: start=%llu not aligned to h/w " | |
a963a956 | 407 | "logical block size %u of %s", |
02acc3a4 MS |
408 | dm_device_name(ti->table->md), |
409 | (unsigned long long)start, | |
754c5fc7 | 410 | limits->logical_block_size, bdevname(bdev, b)); |
f6a1ed10 | 411 | return 1; |
02acc3a4 MS |
412 | } |
413 | ||
5dea271b | 414 | if (len & (logical_block_size_sectors - 1)) { |
02acc3a4 | 415 | DMWARN("%s: len=%llu not aligned to h/w " |
a963a956 | 416 | "logical block size %u of %s", |
02acc3a4 | 417 | dm_device_name(ti->table->md), |
5dea271b | 418 | (unsigned long long)len, |
754c5fc7 | 419 | limits->logical_block_size, bdevname(bdev, b)); |
f6a1ed10 | 420 | return 1; |
02acc3a4 MS |
421 | } |
422 | ||
f6a1ed10 | 423 | return 0; |
1da177e4 LT |
424 | } |
425 | ||
426 | /* | |
570b9d96 | 427 | * This upgrades the mode on an already open dm_dev, being |
1da177e4 | 428 | * careful to leave things as they were if we fail to reopen the |
570b9d96 AK |
429 | * device and not to touch the existing bdev field in case |
430 | * it is accessed concurrently inside dm_table_any_congested(). | |
1da177e4 | 431 | */ |
aeb5d727 | 432 | static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode, |
82b1519b | 433 | struct mapped_device *md) |
1da177e4 LT |
434 | { |
435 | int r; | |
570b9d96 | 436 | struct dm_dev_internal dd_new, dd_old; |
1da177e4 | 437 | |
570b9d96 AK |
438 | dd_new = dd_old = *dd; |
439 | ||
440 | dd_new.dm_dev.mode |= new_mode; | |
441 | dd_new.dm_dev.bdev = NULL; | |
442 | ||
443 | r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md); | |
444 | if (r) | |
445 | return r; | |
1da177e4 | 446 | |
82b1519b | 447 | dd->dm_dev.mode |= new_mode; |
570b9d96 | 448 | close_dev(&dd_old, md); |
1da177e4 | 449 | |
570b9d96 | 450 | return 0; |
1da177e4 LT |
451 | } |
452 | ||
453 | /* | |
454 | * Add a device to the list, or just increment the usage count if | |
455 | * it's already present. | |
456 | */ | |
08649012 MS |
457 | int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, |
458 | struct dm_dev **result) | |
1da177e4 LT |
459 | { |
460 | int r; | |
69a2ce72 | 461 | dev_t uninitialized_var(dev); |
82b1519b | 462 | struct dm_dev_internal *dd; |
1da177e4 | 463 | unsigned int major, minor; |
08649012 | 464 | struct dm_table *t = ti->table; |
1da177e4 | 465 | |
547bc926 | 466 | BUG_ON(!t); |
1da177e4 LT |
467 | |
468 | if (sscanf(path, "%u:%u", &major, &minor) == 2) { | |
469 | /* Extract the major/minor numbers */ | |
470 | dev = MKDEV(major, minor); | |
471 | if (MAJOR(dev) != major || MINOR(dev) != minor) | |
472 | return -EOVERFLOW; | |
473 | } else { | |
474 | /* convert the path to a device */ | |
72e8264e CH |
475 | struct block_device *bdev = lookup_bdev(path); |
476 | ||
477 | if (IS_ERR(bdev)) | |
478 | return PTR_ERR(bdev); | |
479 | dev = bdev->bd_dev; | |
480 | bdput(bdev); | |
1da177e4 LT |
481 | } |
482 | ||
483 | dd = find_device(&t->devices, dev); | |
484 | if (!dd) { | |
485 | dd = kmalloc(sizeof(*dd), GFP_KERNEL); | |
486 | if (!dd) | |
487 | return -ENOMEM; | |
488 | ||
82b1519b MP |
489 | dd->dm_dev.mode = mode; |
490 | dd->dm_dev.bdev = NULL; | |
1da177e4 | 491 | |
f165921d | 492 | if ((r = open_dev(dd, dev, t->md))) { |
1da177e4 LT |
493 | kfree(dd); |
494 | return r; | |
495 | } | |
496 | ||
82b1519b | 497 | format_dev_t(dd->dm_dev.name, dev); |
1da177e4 LT |
498 | |
499 | atomic_set(&dd->count, 0); | |
500 | list_add(&dd->list, &t->devices); | |
501 | ||
82b1519b | 502 | } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) { |
f165921d | 503 | r = upgrade_mode(dd, mode, t->md); |
1da177e4 LT |
504 | if (r) |
505 | return r; | |
506 | } | |
507 | atomic_inc(&dd->count); | |
508 | ||
82b1519b | 509 | *result = &dd->dm_dev; |
1da177e4 LT |
510 | return 0; |
511 | } | |
08649012 | 512 | EXPORT_SYMBOL(dm_get_device); |
1da177e4 | 513 | |
754c5fc7 | 514 | int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev, |
5dea271b | 515 | sector_t start, sector_t len, void *data) |
1da177e4 | 516 | { |
754c5fc7 MS |
517 | struct queue_limits *limits = data; |
518 | struct block_device *bdev = dev->bdev; | |
165125e1 | 519 | struct request_queue *q = bdev_get_queue(bdev); |
0c2322e4 AK |
520 | char b[BDEVNAME_SIZE]; |
521 | ||
522 | if (unlikely(!q)) { | |
523 | DMWARN("%s: Cannot set limits for nonexistent device %s", | |
524 | dm_device_name(ti->table->md), bdevname(bdev, b)); | |
754c5fc7 | 525 | return 0; |
0c2322e4 | 526 | } |
3cb40214 | 527 | |
b27d7f16 MP |
528 | if (bdev_stack_limits(limits, bdev, start) < 0) |
529 | DMWARN("%s: adding target device %s caused an alignment inconsistency: " | |
a963a956 MS |
530 | "physical_block_size=%u, logical_block_size=%u, " |
531 | "alignment_offset=%u, start=%llu", | |
532 | dm_device_name(ti->table->md), bdevname(bdev, b), | |
533 | q->limits.physical_block_size, | |
534 | q->limits.logical_block_size, | |
535 | q->limits.alignment_offset, | |
b27d7f16 | 536 | (unsigned long long) start << SECTOR_SHIFT); |
3cb40214 | 537 | |
9980c638 MB |
538 | /* |
539 | * Check if merge fn is supported. | |
540 | * If not we'll force DM to use PAGE_SIZE or | |
541 | * smaller I/O, just to be safe. | |
3cb40214 | 542 | */ |
d5b9dd04 | 543 | if (dm_queue_merge_is_compulsory(q) && !ti->type->merge) |
72d4cd9f MS |
544 | blk_limits_max_hw_sectors(limits, |
545 | (unsigned int) (PAGE_SIZE >> 9)); | |
754c5fc7 | 546 | return 0; |
3cb40214 BR |
547 | } |
548 | EXPORT_SYMBOL_GPL(dm_set_device_limits); | |
969429b5 | 549 | |
1da177e4 | 550 | /* |
08649012 | 551 | * Decrement a device's use count and remove it if necessary. |
1da177e4 | 552 | */ |
82b1519b | 553 | void dm_put_device(struct dm_target *ti, struct dm_dev *d) |
1da177e4 | 554 | { |
82b1519b MP |
555 | struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal, |
556 | dm_dev); | |
557 | ||
1da177e4 | 558 | if (atomic_dec_and_test(&dd->count)) { |
f165921d | 559 | close_dev(dd, ti->table->md); |
1da177e4 LT |
560 | list_del(&dd->list); |
561 | kfree(dd); | |
562 | } | |
563 | } | |
08649012 | 564 | EXPORT_SYMBOL(dm_put_device); |
1da177e4 LT |
565 | |
566 | /* | |
567 | * Checks to see if the target joins onto the end of the table. | |
568 | */ | |
569 | static int adjoin(struct dm_table *table, struct dm_target *ti) | |
570 | { | |
571 | struct dm_target *prev; | |
572 | ||
573 | if (!table->num_targets) | |
574 | return !ti->begin; | |
575 | ||
576 | prev = &table->targets[table->num_targets - 1]; | |
577 | return (ti->begin == (prev->begin + prev->len)); | |
578 | } | |
579 | ||
580 | /* | |
581 | * Used to dynamically allocate the arg array. | |
582 | */ | |
583 | static char **realloc_argv(unsigned *array_size, char **old_argv) | |
584 | { | |
585 | char **argv; | |
586 | unsigned new_size; | |
587 | ||
588 | new_size = *array_size ? *array_size * 2 : 64; | |
589 | argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL); | |
590 | if (argv) { | |
591 | memcpy(argv, old_argv, *array_size * sizeof(*argv)); | |
592 | *array_size = new_size; | |
593 | } | |
594 | ||
595 | kfree(old_argv); | |
596 | return argv; | |
597 | } | |
598 | ||
599 | /* | |
600 | * Destructively splits up the argument list to pass to ctr. | |
601 | */ | |
602 | int dm_split_args(int *argc, char ***argvp, char *input) | |
603 | { | |
604 | char *start, *end = input, *out, **argv = NULL; | |
605 | unsigned array_size = 0; | |
606 | ||
607 | *argc = 0; | |
814d6862 DT |
608 | |
609 | if (!input) { | |
610 | *argvp = NULL; | |
611 | return 0; | |
612 | } | |
613 | ||
1da177e4 LT |
614 | argv = realloc_argv(&array_size, argv); |
615 | if (!argv) | |
616 | return -ENOMEM; | |
617 | ||
618 | while (1) { | |
1da177e4 | 619 | /* Skip whitespace */ |
e7d2860b | 620 | start = skip_spaces(end); |
1da177e4 LT |
621 | |
622 | if (!*start) | |
623 | break; /* success, we hit the end */ | |
624 | ||
625 | /* 'out' is used to remove any back-quotes */ | |
626 | end = out = start; | |
627 | while (*end) { | |
628 | /* Everything apart from '\0' can be quoted */ | |
629 | if (*end == '\\' && *(end + 1)) { | |
630 | *out++ = *(end + 1); | |
631 | end += 2; | |
632 | continue; | |
633 | } | |
634 | ||
635 | if (isspace(*end)) | |
636 | break; /* end of token */ | |
637 | ||
638 | *out++ = *end++; | |
639 | } | |
640 | ||
641 | /* have we already filled the array ? */ | |
642 | if ((*argc + 1) > array_size) { | |
643 | argv = realloc_argv(&array_size, argv); | |
644 | if (!argv) | |
645 | return -ENOMEM; | |
646 | } | |
647 | ||
648 | /* we know this is whitespace */ | |
649 | if (*end) | |
650 | end++; | |
651 | ||
652 | /* terminate the string and put it in the array */ | |
653 | *out = '\0'; | |
654 | argv[*argc] = start; | |
655 | (*argc)++; | |
656 | } | |
657 | ||
658 | *argvp = argv; | |
659 | return 0; | |
660 | } | |
661 | ||
be6d4305 MS |
662 | /* |
663 | * Impose necessary and sufficient conditions on a devices's table such | |
664 | * that any incoming bio which respects its logical_block_size can be | |
665 | * processed successfully. If it falls across the boundary between | |
666 | * two or more targets, the size of each piece it gets split into must | |
667 | * be compatible with the logical_block_size of the target processing it. | |
668 | */ | |
754c5fc7 MS |
669 | static int validate_hardware_logical_block_alignment(struct dm_table *table, |
670 | struct queue_limits *limits) | |
be6d4305 MS |
671 | { |
672 | /* | |
673 | * This function uses arithmetic modulo the logical_block_size | |
674 | * (in units of 512-byte sectors). | |
675 | */ | |
676 | unsigned short device_logical_block_size_sects = | |
754c5fc7 | 677 | limits->logical_block_size >> SECTOR_SHIFT; |
be6d4305 MS |
678 | |
679 | /* | |
680 | * Offset of the start of the next table entry, mod logical_block_size. | |
681 | */ | |
682 | unsigned short next_target_start = 0; | |
683 | ||
684 | /* | |
685 | * Given an aligned bio that extends beyond the end of a | |
686 | * target, how many sectors must the next target handle? | |
687 | */ | |
688 | unsigned short remaining = 0; | |
689 | ||
690 | struct dm_target *uninitialized_var(ti); | |
754c5fc7 | 691 | struct queue_limits ti_limits; |
be6d4305 MS |
692 | unsigned i = 0; |
693 | ||
694 | /* | |
695 | * Check each entry in the table in turn. | |
696 | */ | |
697 | while (i < dm_table_get_num_targets(table)) { | |
698 | ti = dm_table_get_target(table, i++); | |
699 | ||
754c5fc7 MS |
700 | blk_set_default_limits(&ti_limits); |
701 | ||
702 | /* combine all target devices' limits */ | |
703 | if (ti->type->iterate_devices) | |
704 | ti->type->iterate_devices(ti, dm_set_device_limits, | |
705 | &ti_limits); | |
706 | ||
be6d4305 MS |
707 | /* |
708 | * If the remaining sectors fall entirely within this | |
709 | * table entry are they compatible with its logical_block_size? | |
710 | */ | |
711 | if (remaining < ti->len && | |
754c5fc7 | 712 | remaining & ((ti_limits.logical_block_size >> |
be6d4305 MS |
713 | SECTOR_SHIFT) - 1)) |
714 | break; /* Error */ | |
715 | ||
716 | next_target_start = | |
717 | (unsigned short) ((next_target_start + ti->len) & | |
718 | (device_logical_block_size_sects - 1)); | |
719 | remaining = next_target_start ? | |
720 | device_logical_block_size_sects - next_target_start : 0; | |
721 | } | |
722 | ||
723 | if (remaining) { | |
724 | DMWARN("%s: table line %u (start sect %llu len %llu) " | |
a963a956 | 725 | "not aligned to h/w logical block size %u", |
be6d4305 MS |
726 | dm_device_name(table->md), i, |
727 | (unsigned long long) ti->begin, | |
728 | (unsigned long long) ti->len, | |
754c5fc7 | 729 | limits->logical_block_size); |
be6d4305 MS |
730 | return -EINVAL; |
731 | } | |
732 | ||
733 | return 0; | |
734 | } | |
735 | ||
1da177e4 LT |
736 | int dm_table_add_target(struct dm_table *t, const char *type, |
737 | sector_t start, sector_t len, char *params) | |
738 | { | |
739 | int r = -EINVAL, argc; | |
740 | char **argv; | |
741 | struct dm_target *tgt; | |
742 | ||
743 | if ((r = check_space(t))) | |
744 | return r; | |
745 | ||
746 | tgt = t->targets + t->num_targets; | |
747 | memset(tgt, 0, sizeof(*tgt)); | |
748 | ||
749 | if (!len) { | |
72d94861 | 750 | DMERR("%s: zero-length target", dm_device_name(t->md)); |
1da177e4 LT |
751 | return -EINVAL; |
752 | } | |
753 | ||
754 | tgt->type = dm_get_target_type(type); | |
755 | if (!tgt->type) { | |
72d94861 AK |
756 | DMERR("%s: %s: unknown target type", dm_device_name(t->md), |
757 | type); | |
1da177e4 LT |
758 | return -EINVAL; |
759 | } | |
760 | ||
761 | tgt->table = t; | |
762 | tgt->begin = start; | |
763 | tgt->len = len; | |
764 | tgt->error = "Unknown error"; | |
765 | ||
766 | /* | |
767 | * Does this target adjoin the previous one ? | |
768 | */ | |
769 | if (!adjoin(t, tgt)) { | |
770 | tgt->error = "Gap in table"; | |
771 | r = -EINVAL; | |
772 | goto bad; | |
773 | } | |
774 | ||
775 | r = dm_split_args(&argc, &argv, params); | |
776 | if (r) { | |
777 | tgt->error = "couldn't split parameters (insufficient memory)"; | |
778 | goto bad; | |
779 | } | |
780 | ||
781 | r = tgt->type->ctr(tgt, argc, argv); | |
782 | kfree(argv); | |
783 | if (r) | |
784 | goto bad; | |
785 | ||
786 | t->highs[t->num_targets++] = tgt->begin + tgt->len - 1; | |
787 | ||
936688d7 MS |
788 | if (!tgt->num_discard_requests && tgt->discards_supported) |
789 | DMWARN("%s: %s: ignoring discards_supported because num_discard_requests is zero.", | |
790 | dm_device_name(t->md), type); | |
5ae89a87 | 791 | |
1da177e4 LT |
792 | return 0; |
793 | ||
794 | bad: | |
72d94861 | 795 | DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error); |
1da177e4 LT |
796 | dm_put_target_type(tgt->type); |
797 | return r; | |
798 | } | |
799 | ||
498f0103 MS |
800 | /* |
801 | * Target argument parsing helpers. | |
802 | */ | |
803 | static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set, | |
804 | unsigned *value, char **error, unsigned grouped) | |
805 | { | |
806 | const char *arg_str = dm_shift_arg(arg_set); | |
807 | ||
808 | if (!arg_str || | |
809 | (sscanf(arg_str, "%u", value) != 1) || | |
810 | (*value < arg->min) || | |
811 | (*value > arg->max) || | |
812 | (grouped && arg_set->argc < *value)) { | |
813 | *error = arg->error; | |
814 | return -EINVAL; | |
815 | } | |
816 | ||
817 | return 0; | |
818 | } | |
819 | ||
820 | int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set, | |
821 | unsigned *value, char **error) | |
822 | { | |
823 | return validate_next_arg(arg, arg_set, value, error, 0); | |
824 | } | |
825 | EXPORT_SYMBOL(dm_read_arg); | |
826 | ||
827 | int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set, | |
828 | unsigned *value, char **error) | |
829 | { | |
830 | return validate_next_arg(arg, arg_set, value, error, 1); | |
831 | } | |
832 | EXPORT_SYMBOL(dm_read_arg_group); | |
833 | ||
834 | const char *dm_shift_arg(struct dm_arg_set *as) | |
835 | { | |
836 | char *r; | |
837 | ||
838 | if (as->argc) { | |
839 | as->argc--; | |
840 | r = *as->argv; | |
841 | as->argv++; | |
842 | return r; | |
843 | } | |
844 | ||
845 | return NULL; | |
846 | } | |
847 | EXPORT_SYMBOL(dm_shift_arg); | |
848 | ||
849 | void dm_consume_args(struct dm_arg_set *as, unsigned num_args) | |
850 | { | |
851 | BUG_ON(as->argc < num_args); | |
852 | as->argc -= num_args; | |
853 | as->argv += num_args; | |
854 | } | |
855 | EXPORT_SYMBOL(dm_consume_args); | |
856 | ||
26803b9f | 857 | static int dm_table_set_type(struct dm_table *t) |
e6ee8c0b KU |
858 | { |
859 | unsigned i; | |
860 | unsigned bio_based = 0, request_based = 0; | |
861 | struct dm_target *tgt; | |
862 | struct dm_dev_internal *dd; | |
863 | struct list_head *devices; | |
864 | ||
865 | for (i = 0; i < t->num_targets; i++) { | |
866 | tgt = t->targets + i; | |
867 | if (dm_target_request_based(tgt)) | |
868 | request_based = 1; | |
869 | else | |
870 | bio_based = 1; | |
871 | ||
872 | if (bio_based && request_based) { | |
873 | DMWARN("Inconsistent table: different target types" | |
874 | " can't be mixed up"); | |
875 | return -EINVAL; | |
876 | } | |
877 | } | |
878 | ||
879 | if (bio_based) { | |
880 | /* We must use this table as bio-based */ | |
881 | t->type = DM_TYPE_BIO_BASED; | |
882 | return 0; | |
883 | } | |
884 | ||
885 | BUG_ON(!request_based); /* No targets in this table */ | |
886 | ||
887 | /* Non-request-stackable devices can't be used for request-based dm */ | |
888 | devices = dm_table_get_devices(t); | |
889 | list_for_each_entry(dd, devices, list) { | |
890 | if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) { | |
891 | DMWARN("table load rejected: including" | |
892 | " non-request-stackable devices"); | |
893 | return -EINVAL; | |
894 | } | |
895 | } | |
896 | ||
897 | /* | |
898 | * Request-based dm supports only tables that have a single target now. | |
899 | * To support multiple targets, request splitting support is needed, | |
900 | * and that needs lots of changes in the block-layer. | |
901 | * (e.g. request completion process for partial completion.) | |
902 | */ | |
903 | if (t->num_targets > 1) { | |
904 | DMWARN("Request-based dm doesn't support multiple targets yet"); | |
905 | return -EINVAL; | |
906 | } | |
907 | ||
908 | t->type = DM_TYPE_REQUEST_BASED; | |
909 | ||
910 | return 0; | |
911 | } | |
912 | ||
913 | unsigned dm_table_get_type(struct dm_table *t) | |
914 | { | |
915 | return t->type; | |
916 | } | |
917 | ||
918 | bool dm_table_request_based(struct dm_table *t) | |
919 | { | |
920 | return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED; | |
921 | } | |
922 | ||
923 | int dm_table_alloc_md_mempools(struct dm_table *t) | |
924 | { | |
925 | unsigned type = dm_table_get_type(t); | |
926 | ||
927 | if (unlikely(type == DM_TYPE_NONE)) { | |
928 | DMWARN("no table type is set, can't allocate mempools"); | |
929 | return -EINVAL; | |
930 | } | |
931 | ||
a91a2785 | 932 | t->mempools = dm_alloc_md_mempools(type, t->integrity_supported); |
e6ee8c0b KU |
933 | if (!t->mempools) |
934 | return -ENOMEM; | |
935 | ||
936 | return 0; | |
937 | } | |
938 | ||
939 | void dm_table_free_md_mempools(struct dm_table *t) | |
940 | { | |
941 | dm_free_md_mempools(t->mempools); | |
942 | t->mempools = NULL; | |
943 | } | |
944 | ||
945 | struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t) | |
946 | { | |
947 | return t->mempools; | |
948 | } | |
949 | ||
1da177e4 LT |
950 | static int setup_indexes(struct dm_table *t) |
951 | { | |
952 | int i; | |
953 | unsigned int total = 0; | |
954 | sector_t *indexes; | |
955 | ||
956 | /* allocate the space for *all* the indexes */ | |
957 | for (i = t->depth - 2; i >= 0; i--) { | |
958 | t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE); | |
959 | total += t->counts[i]; | |
960 | } | |
961 | ||
962 | indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE); | |
963 | if (!indexes) | |
964 | return -ENOMEM; | |
965 | ||
966 | /* set up internal nodes, bottom-up */ | |
82d601dc | 967 | for (i = t->depth - 2; i >= 0; i--) { |
1da177e4 LT |
968 | t->index[i] = indexes; |
969 | indexes += (KEYS_PER_NODE * t->counts[i]); | |
970 | setup_btree_index(i, t); | |
971 | } | |
972 | ||
973 | return 0; | |
974 | } | |
975 | ||
976 | /* | |
977 | * Builds the btree to index the map. | |
978 | */ | |
26803b9f | 979 | static int dm_table_build_index(struct dm_table *t) |
1da177e4 LT |
980 | { |
981 | int r = 0; | |
982 | unsigned int leaf_nodes; | |
983 | ||
1da177e4 LT |
984 | /* how many indexes will the btree have ? */ |
985 | leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE); | |
986 | t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE); | |
987 | ||
988 | /* leaf layer has already been set up */ | |
989 | t->counts[t->depth - 1] = leaf_nodes; | |
990 | t->index[t->depth - 1] = t->highs; | |
991 | ||
992 | if (t->depth >= 2) | |
993 | r = setup_indexes(t); | |
994 | ||
995 | return r; | |
996 | } | |
997 | ||
a63a5cf8 MS |
998 | /* |
999 | * Get a disk whose integrity profile reflects the table's profile. | |
1000 | * If %match_all is true, all devices' profiles must match. | |
1001 | * If %match_all is false, all devices must at least have an | |
1002 | * allocated integrity profile; but uninitialized is ok. | |
1003 | * Returns NULL if integrity support was inconsistent or unavailable. | |
1004 | */ | |
1005 | static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t, | |
1006 | bool match_all) | |
1007 | { | |
1008 | struct list_head *devices = dm_table_get_devices(t); | |
1009 | struct dm_dev_internal *dd = NULL; | |
1010 | struct gendisk *prev_disk = NULL, *template_disk = NULL; | |
1011 | ||
1012 | list_for_each_entry(dd, devices, list) { | |
1013 | template_disk = dd->dm_dev.bdev->bd_disk; | |
1014 | if (!blk_get_integrity(template_disk)) | |
1015 | goto no_integrity; | |
1016 | if (!match_all && !blk_integrity_is_initialized(template_disk)) | |
1017 | continue; /* skip uninitialized profiles */ | |
1018 | else if (prev_disk && | |
1019 | blk_integrity_compare(prev_disk, template_disk) < 0) | |
1020 | goto no_integrity; | |
1021 | prev_disk = template_disk; | |
1022 | } | |
1023 | ||
1024 | return template_disk; | |
1025 | ||
1026 | no_integrity: | |
1027 | if (prev_disk) | |
1028 | DMWARN("%s: integrity not set: %s and %s profile mismatch", | |
1029 | dm_device_name(t->md), | |
1030 | prev_disk->disk_name, | |
1031 | template_disk->disk_name); | |
1032 | return NULL; | |
1033 | } | |
1034 | ||
26803b9f WD |
1035 | /* |
1036 | * Register the mapped device for blk_integrity support if | |
a63a5cf8 MS |
1037 | * the underlying devices have an integrity profile. But all devices |
1038 | * may not have matching profiles (checking all devices isn't reliable | |
1039 | * during table load because this table may use other DM device(s) which | |
1040 | * must be resumed before they will have an initialized integity profile). | |
1041 | * Stacked DM devices force a 2 stage integrity profile validation: | |
1042 | * 1 - during load, validate all initialized integrity profiles match | |
1043 | * 2 - during resume, validate all integrity profiles match | |
26803b9f WD |
1044 | */ |
1045 | static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md) | |
1046 | { | |
a63a5cf8 | 1047 | struct gendisk *template_disk = NULL; |
26803b9f | 1048 | |
a63a5cf8 MS |
1049 | template_disk = dm_table_get_integrity_disk(t, false); |
1050 | if (!template_disk) | |
1051 | return 0; | |
26803b9f | 1052 | |
a63a5cf8 MS |
1053 | if (!blk_integrity_is_initialized(dm_disk(md))) { |
1054 | t->integrity_supported = 1; | |
1055 | return blk_integrity_register(dm_disk(md), NULL); | |
1056 | } | |
1057 | ||
1058 | /* | |
1059 | * If DM device already has an initalized integrity | |
1060 | * profile the new profile should not conflict. | |
1061 | */ | |
1062 | if (blk_integrity_is_initialized(template_disk) && | |
1063 | blk_integrity_compare(dm_disk(md), template_disk) < 0) { | |
1064 | DMWARN("%s: conflict with existing integrity profile: " | |
1065 | "%s profile mismatch", | |
1066 | dm_device_name(t->md), | |
1067 | template_disk->disk_name); | |
1068 | return 1; | |
1069 | } | |
1070 | ||
1071 | /* Preserve existing initialized integrity profile */ | |
1072 | t->integrity_supported = 1; | |
26803b9f WD |
1073 | return 0; |
1074 | } | |
1075 | ||
1076 | /* | |
1077 | * Prepares the table for use by building the indices, | |
1078 | * setting the type, and allocating mempools. | |
1079 | */ | |
1080 | int dm_table_complete(struct dm_table *t) | |
1081 | { | |
1082 | int r; | |
1083 | ||
1084 | r = dm_table_set_type(t); | |
1085 | if (r) { | |
1086 | DMERR("unable to set table type"); | |
1087 | return r; | |
1088 | } | |
1089 | ||
1090 | r = dm_table_build_index(t); | |
1091 | if (r) { | |
1092 | DMERR("unable to build btrees"); | |
1093 | return r; | |
1094 | } | |
1095 | ||
1096 | r = dm_table_prealloc_integrity(t, t->md); | |
1097 | if (r) { | |
1098 | DMERR("could not register integrity profile."); | |
1099 | return r; | |
1100 | } | |
1101 | ||
1102 | r = dm_table_alloc_md_mempools(t); | |
1103 | if (r) | |
1104 | DMERR("unable to allocate mempools"); | |
1105 | ||
1106 | return r; | |
1107 | } | |
1108 | ||
48c9c27b | 1109 | static DEFINE_MUTEX(_event_lock); |
1da177e4 LT |
1110 | void dm_table_event_callback(struct dm_table *t, |
1111 | void (*fn)(void *), void *context) | |
1112 | { | |
48c9c27b | 1113 | mutex_lock(&_event_lock); |
1da177e4 LT |
1114 | t->event_fn = fn; |
1115 | t->event_context = context; | |
48c9c27b | 1116 | mutex_unlock(&_event_lock); |
1da177e4 LT |
1117 | } |
1118 | ||
1119 | void dm_table_event(struct dm_table *t) | |
1120 | { | |
1121 | /* | |
1122 | * You can no longer call dm_table_event() from interrupt | |
1123 | * context, use a bottom half instead. | |
1124 | */ | |
1125 | BUG_ON(in_interrupt()); | |
1126 | ||
48c9c27b | 1127 | mutex_lock(&_event_lock); |
1da177e4 LT |
1128 | if (t->event_fn) |
1129 | t->event_fn(t->event_context); | |
48c9c27b | 1130 | mutex_unlock(&_event_lock); |
1da177e4 | 1131 | } |
08649012 | 1132 | EXPORT_SYMBOL(dm_table_event); |
1da177e4 LT |
1133 | |
1134 | sector_t dm_table_get_size(struct dm_table *t) | |
1135 | { | |
1136 | return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0; | |
1137 | } | |
08649012 | 1138 | EXPORT_SYMBOL(dm_table_get_size); |
1da177e4 LT |
1139 | |
1140 | struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index) | |
1141 | { | |
14353539 | 1142 | if (index >= t->num_targets) |
1da177e4 LT |
1143 | return NULL; |
1144 | ||
1145 | return t->targets + index; | |
1146 | } | |
1147 | ||
1148 | /* | |
1149 | * Search the btree for the correct target. | |
512875bd JN |
1150 | * |
1151 | * Caller should check returned pointer with dm_target_is_valid() | |
1152 | * to trap I/O beyond end of device. | |
1da177e4 LT |
1153 | */ |
1154 | struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) | |
1155 | { | |
1156 | unsigned int l, n = 0, k = 0; | |
1157 | sector_t *node; | |
1158 | ||
1159 | for (l = 0; l < t->depth; l++) { | |
1160 | n = get_child(n, k); | |
1161 | node = get_node(t, l, n); | |
1162 | ||
1163 | for (k = 0; k < KEYS_PER_NODE; k++) | |
1164 | if (node[k] >= sector) | |
1165 | break; | |
1166 | } | |
1167 | ||
1168 | return &t->targets[(KEYS_PER_NODE * n) + k]; | |
1169 | } | |
1170 | ||
754c5fc7 MS |
1171 | /* |
1172 | * Establish the new table's queue_limits and validate them. | |
1173 | */ | |
1174 | int dm_calculate_queue_limits(struct dm_table *table, | |
1175 | struct queue_limits *limits) | |
1176 | { | |
1177 | struct dm_target *uninitialized_var(ti); | |
1178 | struct queue_limits ti_limits; | |
1179 | unsigned i = 0; | |
1180 | ||
1181 | blk_set_default_limits(limits); | |
1182 | ||
1183 | while (i < dm_table_get_num_targets(table)) { | |
1184 | blk_set_default_limits(&ti_limits); | |
1185 | ||
1186 | ti = dm_table_get_target(table, i++); | |
1187 | ||
1188 | if (!ti->type->iterate_devices) | |
1189 | goto combine_limits; | |
1190 | ||
1191 | /* | |
1192 | * Combine queue limits of all the devices this target uses. | |
1193 | */ | |
1194 | ti->type->iterate_devices(ti, dm_set_device_limits, | |
1195 | &ti_limits); | |
1196 | ||
40bea431 MS |
1197 | /* Set I/O hints portion of queue limits */ |
1198 | if (ti->type->io_hints) | |
1199 | ti->type->io_hints(ti, &ti_limits); | |
1200 | ||
754c5fc7 MS |
1201 | /* |
1202 | * Check each device area is consistent with the target's | |
1203 | * overall queue limits. | |
1204 | */ | |
f6a1ed10 MP |
1205 | if (ti->type->iterate_devices(ti, device_area_is_invalid, |
1206 | &ti_limits)) | |
754c5fc7 MS |
1207 | return -EINVAL; |
1208 | ||
1209 | combine_limits: | |
1210 | /* | |
1211 | * Merge this target's queue limits into the overall limits | |
1212 | * for the table. | |
1213 | */ | |
1214 | if (blk_stack_limits(limits, &ti_limits, 0) < 0) | |
b27d7f16 | 1215 | DMWARN("%s: adding target device " |
754c5fc7 | 1216 | "(start sect %llu len %llu) " |
b27d7f16 | 1217 | "caused an alignment inconsistency", |
754c5fc7 MS |
1218 | dm_device_name(table->md), |
1219 | (unsigned long long) ti->begin, | |
1220 | (unsigned long long) ti->len); | |
1221 | } | |
1222 | ||
1223 | return validate_hardware_logical_block_alignment(table, limits); | |
1224 | } | |
1225 | ||
9c47008d MP |
1226 | /* |
1227 | * Set the integrity profile for this device if all devices used have | |
a63a5cf8 MS |
1228 | * matching profiles. We're quite deep in the resume path but still |
1229 | * don't know if all devices (particularly DM devices this device | |
1230 | * may be stacked on) have matching profiles. Even if the profiles | |
1231 | * don't match we have no way to fail (to resume) at this point. | |
9c47008d MP |
1232 | */ |
1233 | static void dm_table_set_integrity(struct dm_table *t) | |
1234 | { | |
a63a5cf8 | 1235 | struct gendisk *template_disk = NULL; |
9c47008d MP |
1236 | |
1237 | if (!blk_get_integrity(dm_disk(t->md))) | |
1238 | return; | |
1239 | ||
a63a5cf8 MS |
1240 | template_disk = dm_table_get_integrity_disk(t, true); |
1241 | if (!template_disk && | |
1242 | blk_integrity_is_initialized(dm_disk(t->md))) { | |
1243 | DMWARN("%s: device no longer has a valid integrity profile", | |
1244 | dm_device_name(t->md)); | |
1245 | return; | |
9c47008d | 1246 | } |
9c47008d | 1247 | blk_integrity_register(dm_disk(t->md), |
a63a5cf8 | 1248 | blk_get_integrity(template_disk)); |
9c47008d MP |
1249 | } |
1250 | ||
ed8b752b MS |
1251 | static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev, |
1252 | sector_t start, sector_t len, void *data) | |
1253 | { | |
1254 | unsigned flush = (*(unsigned *)data); | |
1255 | struct request_queue *q = bdev_get_queue(dev->bdev); | |
1256 | ||
1257 | return q && (q->flush_flags & flush); | |
1258 | } | |
1259 | ||
1260 | static bool dm_table_supports_flush(struct dm_table *t, unsigned flush) | |
1261 | { | |
1262 | struct dm_target *ti; | |
1263 | unsigned i = 0; | |
1264 | ||
1265 | /* | |
1266 | * Require at least one underlying device to support flushes. | |
1267 | * t->devices includes internal dm devices such as mirror logs | |
1268 | * so we need to use iterate_devices here, which targets | |
1269 | * supporting flushes must provide. | |
1270 | */ | |
1271 | while (i < dm_table_get_num_targets(t)) { | |
1272 | ti = dm_table_get_target(t, i++); | |
1273 | ||
1274 | if (!ti->num_flush_requests) | |
1275 | continue; | |
1276 | ||
1277 | if (ti->type->iterate_devices && | |
1278 | ti->type->iterate_devices(ti, device_flush_capable, &flush)) | |
1279 | return 1; | |
1280 | } | |
1281 | ||
1282 | return 0; | |
1283 | } | |
1284 | ||
754c5fc7 MS |
1285 | void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, |
1286 | struct queue_limits *limits) | |
1da177e4 | 1287 | { |
ed8b752b MS |
1288 | unsigned flush = 0; |
1289 | ||
1da177e4 | 1290 | /* |
1197764e | 1291 | * Copy table's limits to the DM device's request_queue |
1da177e4 | 1292 | */ |
754c5fc7 | 1293 | q->limits = *limits; |
c9a3f6d6 | 1294 | |
5ae89a87 MS |
1295 | if (!dm_table_supports_discards(t)) |
1296 | queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q); | |
1297 | else | |
1298 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q); | |
1299 | ||
ed8b752b MS |
1300 | if (dm_table_supports_flush(t, REQ_FLUSH)) { |
1301 | flush |= REQ_FLUSH; | |
1302 | if (dm_table_supports_flush(t, REQ_FUA)) | |
1303 | flush |= REQ_FUA; | |
1304 | } | |
1305 | blk_queue_flush(q, flush); | |
1306 | ||
9c47008d | 1307 | dm_table_set_integrity(t); |
e6ee8c0b KU |
1308 | |
1309 | /* | |
1310 | * QUEUE_FLAG_STACKABLE must be set after all queue settings are | |
1311 | * visible to other CPUs because, once the flag is set, incoming bios | |
1312 | * are processed by request-based dm, which refers to the queue | |
1313 | * settings. | |
1314 | * Until the flag set, bios are passed to bio-based dm and queued to | |
1315 | * md->deferred where queue settings are not needed yet. | |
1316 | * Those bios are passed to request-based dm at the resume time. | |
1317 | */ | |
1318 | smp_mb(); | |
1319 | if (dm_table_request_based(t)) | |
1320 | queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q); | |
1da177e4 LT |
1321 | } |
1322 | ||
1323 | unsigned int dm_table_get_num_targets(struct dm_table *t) | |
1324 | { | |
1325 | return t->num_targets; | |
1326 | } | |
1327 | ||
1328 | struct list_head *dm_table_get_devices(struct dm_table *t) | |
1329 | { | |
1330 | return &t->devices; | |
1331 | } | |
1332 | ||
aeb5d727 | 1333 | fmode_t dm_table_get_mode(struct dm_table *t) |
1da177e4 LT |
1334 | { |
1335 | return t->mode; | |
1336 | } | |
08649012 | 1337 | EXPORT_SYMBOL(dm_table_get_mode); |
1da177e4 LT |
1338 | |
1339 | static void suspend_targets(struct dm_table *t, unsigned postsuspend) | |
1340 | { | |
1341 | int i = t->num_targets; | |
1342 | struct dm_target *ti = t->targets; | |
1343 | ||
1344 | while (i--) { | |
1345 | if (postsuspend) { | |
1346 | if (ti->type->postsuspend) | |
1347 | ti->type->postsuspend(ti); | |
1348 | } else if (ti->type->presuspend) | |
1349 | ti->type->presuspend(ti); | |
1350 | ||
1351 | ti++; | |
1352 | } | |
1353 | } | |
1354 | ||
1355 | void dm_table_presuspend_targets(struct dm_table *t) | |
1356 | { | |
cf222b37 AK |
1357 | if (!t) |
1358 | return; | |
1359 | ||
e8488d08 | 1360 | suspend_targets(t, 0); |
1da177e4 LT |
1361 | } |
1362 | ||
1363 | void dm_table_postsuspend_targets(struct dm_table *t) | |
1364 | { | |
cf222b37 AK |
1365 | if (!t) |
1366 | return; | |
1367 | ||
e8488d08 | 1368 | suspend_targets(t, 1); |
1da177e4 LT |
1369 | } |
1370 | ||
8757b776 | 1371 | int dm_table_resume_targets(struct dm_table *t) |
1da177e4 | 1372 | { |
8757b776 MB |
1373 | int i, r = 0; |
1374 | ||
1375 | for (i = 0; i < t->num_targets; i++) { | |
1376 | struct dm_target *ti = t->targets + i; | |
1377 | ||
1378 | if (!ti->type->preresume) | |
1379 | continue; | |
1380 | ||
1381 | r = ti->type->preresume(ti); | |
1382 | if (r) | |
1383 | return r; | |
1384 | } | |
1da177e4 LT |
1385 | |
1386 | for (i = 0; i < t->num_targets; i++) { | |
1387 | struct dm_target *ti = t->targets + i; | |
1388 | ||
1389 | if (ti->type->resume) | |
1390 | ti->type->resume(ti); | |
1391 | } | |
8757b776 MB |
1392 | |
1393 | return 0; | |
1da177e4 LT |
1394 | } |
1395 | ||
9d357b07 N |
1396 | void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb) |
1397 | { | |
1398 | list_add(&cb->list, &t->target_callbacks); | |
1399 | } | |
1400 | EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks); | |
1401 | ||
1da177e4 LT |
1402 | int dm_table_any_congested(struct dm_table *t, int bdi_bits) |
1403 | { | |
82b1519b | 1404 | struct dm_dev_internal *dd; |
afb24528 | 1405 | struct list_head *devices = dm_table_get_devices(t); |
9d357b07 | 1406 | struct dm_target_callbacks *cb; |
1da177e4 LT |
1407 | int r = 0; |
1408 | ||
afb24528 | 1409 | list_for_each_entry(dd, devices, list) { |
82b1519b | 1410 | struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev); |
0c2322e4 AK |
1411 | char b[BDEVNAME_SIZE]; |
1412 | ||
1413 | if (likely(q)) | |
1414 | r |= bdi_congested(&q->backing_dev_info, bdi_bits); | |
1415 | else | |
1416 | DMWARN_LIMIT("%s: any_congested: nonexistent device %s", | |
1417 | dm_device_name(t->md), | |
1418 | bdevname(dd->dm_dev.bdev, b)); | |
1da177e4 LT |
1419 | } |
1420 | ||
9d357b07 N |
1421 | list_for_each_entry(cb, &t->target_callbacks, list) |
1422 | if (cb->congested_fn) | |
1423 | r |= cb->congested_fn(cb, bdi_bits); | |
1424 | ||
1da177e4 LT |
1425 | return r; |
1426 | } | |
1427 | ||
cec47e3d KU |
1428 | int dm_table_any_busy_target(struct dm_table *t) |
1429 | { | |
1430 | unsigned i; | |
1431 | struct dm_target *ti; | |
1432 | ||
1433 | for (i = 0; i < t->num_targets; i++) { | |
1434 | ti = t->targets + i; | |
1435 | if (ti->type->busy && ti->type->busy(ti)) | |
1436 | return 1; | |
1437 | } | |
1438 | ||
1439 | return 0; | |
1440 | } | |
1441 | ||
1134e5ae MA |
1442 | struct mapped_device *dm_table_get_md(struct dm_table *t) |
1443 | { | |
1134e5ae MA |
1444 | return t->md; |
1445 | } | |
08649012 | 1446 | EXPORT_SYMBOL(dm_table_get_md); |
1134e5ae | 1447 | |
5ae89a87 MS |
1448 | static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev, |
1449 | sector_t start, sector_t len, void *data) | |
1450 | { | |
1451 | struct request_queue *q = bdev_get_queue(dev->bdev); | |
1452 | ||
1453 | return q && blk_queue_discard(q); | |
1454 | } | |
1455 | ||
1456 | bool dm_table_supports_discards(struct dm_table *t) | |
1457 | { | |
1458 | struct dm_target *ti; | |
1459 | unsigned i = 0; | |
1460 | ||
5ae89a87 | 1461 | /* |
4c259327 MS |
1462 | * Unless any target used by the table set discards_supported, |
1463 | * require at least one underlying device to support discards. | |
5ae89a87 MS |
1464 | * t->devices includes internal dm devices such as mirror logs |
1465 | * so we need to use iterate_devices here, which targets | |
936688d7 | 1466 | * supporting discard selectively must provide. |
5ae89a87 MS |
1467 | */ |
1468 | while (i < dm_table_get_num_targets(t)) { | |
1469 | ti = dm_table_get_target(t, i++); | |
1470 | ||
936688d7 MS |
1471 | if (!ti->num_discard_requests) |
1472 | continue; | |
1473 | ||
4c259327 MS |
1474 | if (ti->discards_supported) |
1475 | return 1; | |
1476 | ||
5ae89a87 MS |
1477 | if (ti->type->iterate_devices && |
1478 | ti->type->iterate_devices(ti, device_discard_capable, NULL)) | |
1479 | return 1; | |
1480 | } | |
1481 | ||
1482 | return 0; | |
1483 | } |