Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2001 Sistina Software (UK) Limited. |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 3 | * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
André Goddard Rosa | e7d2860 | 2009-12-14 18:01:06 -0800 | [diff] [blame] | 15 | #include <linux/string.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/slab.h> |
| 17 | #include <linux/interrupt.h> |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 18 | #include <linux/mutex.h> |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 19 | #include <linux/delay.h> |
Arun Sharma | 6006349 | 2011-07-26 16:09:06 -0700 | [diff] [blame] | 20 | #include <linux/atomic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 22 | #define DM_MSG_PREFIX "table" |
| 23 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | struct dm_table { |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 43 | struct mapped_device *md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | atomic_t holders; |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 45 | unsigned type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Alasdair G Kergon | 36a0456 | 2011-10-31 20:19:04 +0000 | [diff] [blame] | 57 | struct target_type *immutable_target_type; |
Martin K. Petersen | a91a278 | 2011-03-17 11:11:05 +0100 | [diff] [blame] | 58 | unsigned integrity_supported:1; |
Alasdair G Kergon | 3791e2f | 2011-10-31 20:19:00 +0000 | [diff] [blame] | 59 | unsigned singleton:1; |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 60 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | /* |
| 62 | * Indicates the rw permissions for the new logical |
| 63 | * device. This should be a combination of FMODE_READ |
| 64 | * and FMODE_WRITE. |
| 65 | */ |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 66 | fmode_t mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | |
| 68 | /* a list of devices used by this table */ |
| 69 | struct list_head devices; |
| 70 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | /* events get handed up using this callback */ |
| 72 | void (*event_fn)(void *); |
| 73 | void *event_context; |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 74 | |
| 75 | struct dm_md_mempools *mempools; |
NeilBrown | 9d357b0 | 2011-01-13 20:00:01 +0000 | [diff] [blame] | 76 | |
| 77 | struct list_head target_callbacks; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | }; |
| 79 | |
| 80 | /* |
| 81 | * Similar to ceiling(log_size(n)) |
| 82 | */ |
| 83 | static unsigned int int_log(unsigned int n, unsigned int base) |
| 84 | { |
| 85 | int result = 0; |
| 86 | |
| 87 | while (n > 1) { |
| 88 | n = dm_div_up(n, base); |
| 89 | result++; |
| 90 | } |
| 91 | |
| 92 | return result; |
| 93 | } |
| 94 | |
| 95 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | * Calculate the index of the child node of the n'th node k'th key. |
| 97 | */ |
| 98 | static inline unsigned int get_child(unsigned int n, unsigned int k) |
| 99 | { |
| 100 | return (n * CHILDREN_PER_NODE) + k; |
| 101 | } |
| 102 | |
| 103 | /* |
| 104 | * Return the n'th node of level l from table t. |
| 105 | */ |
| 106 | static inline sector_t *get_node(struct dm_table *t, |
| 107 | unsigned int l, unsigned int n) |
| 108 | { |
| 109 | return t->index[l] + (n * KEYS_PER_NODE); |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * Return the highest key that you could lookup from the n'th |
| 114 | * node on level l of the btree. |
| 115 | */ |
| 116 | static sector_t high(struct dm_table *t, unsigned int l, unsigned int n) |
| 117 | { |
| 118 | for (; l < t->depth - 1; l++) |
| 119 | n = get_child(n, CHILDREN_PER_NODE - 1); |
| 120 | |
| 121 | if (n >= t->counts[l]) |
| 122 | return (sector_t) - 1; |
| 123 | |
| 124 | return get_node(t, l, n)[KEYS_PER_NODE - 1]; |
| 125 | } |
| 126 | |
| 127 | /* |
| 128 | * Fills in a level of the btree based on the highs of the level |
| 129 | * below it. |
| 130 | */ |
| 131 | static int setup_btree_index(unsigned int l, struct dm_table *t) |
| 132 | { |
| 133 | unsigned int n, k; |
| 134 | sector_t *node; |
| 135 | |
| 136 | for (n = 0U; n < t->counts[l]; n++) { |
| 137 | node = get_node(t, l, n); |
| 138 | |
| 139 | for (k = 0U; k < KEYS_PER_NODE; k++) |
| 140 | node[k] = high(t, l + 1, get_child(n, k)); |
| 141 | } |
| 142 | |
| 143 | return 0; |
| 144 | } |
| 145 | |
| 146 | void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size) |
| 147 | { |
| 148 | unsigned long size; |
| 149 | void *addr; |
| 150 | |
| 151 | /* |
| 152 | * Check that we're not going to overflow. |
| 153 | */ |
| 154 | if (nmemb > (ULONG_MAX / elem_size)) |
| 155 | return NULL; |
| 156 | |
| 157 | size = nmemb * elem_size; |
Joe Perches | e29e65a | 2011-08-02 12:32:02 +0100 | [diff] [blame] | 158 | addr = vzalloc(size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | |
| 160 | return addr; |
| 161 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 162 | EXPORT_SYMBOL(dm_vcalloc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | |
| 164 | /* |
| 165 | * highs, and targets are managed as dynamic arrays during a |
| 166 | * table load. |
| 167 | */ |
| 168 | static int alloc_targets(struct dm_table *t, unsigned int num) |
| 169 | { |
| 170 | sector_t *n_highs; |
| 171 | struct dm_target *n_targets; |
| 172 | int n = t->num_targets; |
| 173 | |
| 174 | /* |
| 175 | * Allocate both the target array and offset array at once. |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 176 | * Append an empty entry to catch sectors beyond the end of |
| 177 | * the device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | */ |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 179 | n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) + |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | sizeof(sector_t)); |
| 181 | if (!n_highs) |
| 182 | return -ENOMEM; |
| 183 | |
| 184 | n_targets = (struct dm_target *) (n_highs + num); |
| 185 | |
| 186 | if (n) { |
| 187 | memcpy(n_highs, t->highs, sizeof(*n_highs) * n); |
| 188 | memcpy(n_targets, t->targets, sizeof(*n_targets) * n); |
| 189 | } |
| 190 | |
| 191 | memset(n_highs + n, -1, sizeof(*n_highs) * (num - n)); |
| 192 | vfree(t->highs); |
| 193 | |
| 194 | t->num_allocated = num; |
| 195 | t->highs = n_highs; |
| 196 | t->targets = n_targets; |
| 197 | |
| 198 | return 0; |
| 199 | } |
| 200 | |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 201 | int dm_table_create(struct dm_table **result, fmode_t mode, |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 202 | unsigned num_targets, struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | { |
Dmitry Monakhov | 094262d | 2007-10-19 22:38:51 +0100 | [diff] [blame] | 204 | struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | |
| 206 | if (!t) |
| 207 | return -ENOMEM; |
| 208 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | INIT_LIST_HEAD(&t->devices); |
NeilBrown | 9d357b0 | 2011-01-13 20:00:01 +0000 | [diff] [blame] | 210 | INIT_LIST_HEAD(&t->target_callbacks); |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 211 | atomic_set(&t->holders, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | |
| 213 | if (!num_targets) |
| 214 | num_targets = KEYS_PER_NODE; |
| 215 | |
| 216 | num_targets = dm_round_up(num_targets, KEYS_PER_NODE); |
| 217 | |
| 218 | if (alloc_targets(t, num_targets)) { |
| 219 | kfree(t); |
| 220 | t = NULL; |
| 221 | return -ENOMEM; |
| 222 | } |
| 223 | |
| 224 | t->mode = mode; |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 225 | t->md = md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | *result = t; |
| 227 | return 0; |
| 228 | } |
| 229 | |
| 230 | static void free_devices(struct list_head *devices) |
| 231 | { |
| 232 | struct list_head *tmp, *next; |
| 233 | |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 234 | list_for_each_safe(tmp, next, devices) { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 235 | struct dm_dev_internal *dd = |
| 236 | list_entry(tmp, struct dm_dev_internal, list); |
Jonthan Brassow | 1b6da75 | 2009-06-22 10:12:29 +0100 | [diff] [blame] | 237 | DMWARN("dm_table_destroy: dm_put_device call missing for %s", |
| 238 | dd->dm_dev.name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | kfree(dd); |
| 240 | } |
| 241 | } |
| 242 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 243 | void dm_table_destroy(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | { |
| 245 | unsigned int i; |
| 246 | |
Alasdair G Kergon | a794015 | 2009-12-10 23:52:23 +0000 | [diff] [blame] | 247 | if (!t) |
| 248 | return; |
| 249 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 250 | while (atomic_read(&t->holders)) |
| 251 | msleep(1); |
| 252 | smp_mb(); |
| 253 | |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 254 | /* free the indexes */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | if (t->depth >= 2) |
| 256 | vfree(t->index[t->depth - 2]); |
| 257 | |
| 258 | /* free the targets */ |
| 259 | for (i = 0; i < t->num_targets; i++) { |
| 260 | struct dm_target *tgt = t->targets + i; |
| 261 | |
| 262 | if (tgt->type->dtr) |
| 263 | tgt->type->dtr(tgt); |
| 264 | |
| 265 | dm_put_target_type(tgt->type); |
| 266 | } |
| 267 | |
| 268 | vfree(t->highs); |
| 269 | |
| 270 | /* free the device list */ |
Jonthan Brassow | 1b6da75 | 2009-06-22 10:12:29 +0100 | [diff] [blame] | 271 | if (t->devices.next != &t->devices) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | free_devices(&t->devices); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 274 | dm_free_md_mempools(t->mempools); |
| 275 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | kfree(t); |
| 277 | } |
| 278 | |
| 279 | void dm_table_get(struct dm_table *t) |
| 280 | { |
| 281 | atomic_inc(&t->holders); |
| 282 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 283 | EXPORT_SYMBOL(dm_table_get); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | |
| 285 | void dm_table_put(struct dm_table *t) |
| 286 | { |
| 287 | if (!t) |
| 288 | return; |
| 289 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 290 | smp_mb__before_atomic_dec(); |
| 291 | atomic_dec(&t->holders); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 293 | EXPORT_SYMBOL(dm_table_put); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | |
| 295 | /* |
| 296 | * Checks to see if we need to extend highs or targets. |
| 297 | */ |
| 298 | static inline int check_space(struct dm_table *t) |
| 299 | { |
| 300 | if (t->num_targets >= t->num_allocated) |
| 301 | return alloc_targets(t, t->num_allocated * 2); |
| 302 | |
| 303 | return 0; |
| 304 | } |
| 305 | |
| 306 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | * See if we've already got a device in the list. |
| 308 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 309 | static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 311 | struct dm_dev_internal *dd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | |
| 313 | list_for_each_entry (dd, l, list) |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 314 | if (dd->dm_dev.bdev->bd_dev == dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 315 | return dd; |
| 316 | |
| 317 | return NULL; |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * Open a device so we can use it as a map destination. |
| 322 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 323 | static int open_dev(struct dm_dev_internal *d, dev_t dev, |
| 324 | struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
| 326 | static char *_claim_ptr = "I belong to device-mapper"; |
| 327 | struct block_device *bdev; |
| 328 | |
| 329 | int r; |
| 330 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 331 | BUG_ON(d->dm_dev.bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | |
Tejun Heo | d4d7762 | 2010-11-13 11:55:18 +0100 | [diff] [blame] | 333 | bdev = blkdev_get_by_dev(dev, d->dm_dev.mode | FMODE_EXCL, _claim_ptr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | if (IS_ERR(bdev)) |
| 335 | return PTR_ERR(bdev); |
Tejun Heo | e09b457 | 2010-11-13 11:55:17 +0100 | [diff] [blame] | 336 | |
Tejun Heo | e09b457 | 2010-11-13 11:55:17 +0100 | [diff] [blame] | 337 | r = bd_link_disk_holder(bdev, dm_disk(md)); |
| 338 | if (r) { |
Tejun Heo | e525fd8 | 2010-11-13 11:55:17 +0100 | [diff] [blame] | 339 | blkdev_put(bdev, d->dm_dev.mode | FMODE_EXCL); |
Tejun Heo | e09b457 | 2010-11-13 11:55:17 +0100 | [diff] [blame] | 340 | return r; |
| 341 | } |
| 342 | |
| 343 | d->dm_dev.bdev = bdev; |
| 344 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | } |
| 346 | |
| 347 | /* |
| 348 | * Close a device that we've been using. |
| 349 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 350 | static void close_dev(struct dm_dev_internal *d, struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 352 | if (!d->dm_dev.bdev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | return; |
| 354 | |
Tejun Heo | 49731ba | 2011-01-14 18:43:57 +0100 | [diff] [blame] | 355 | bd_unlink_disk_holder(d->dm_dev.bdev, dm_disk(md)); |
Tejun Heo | e525fd8 | 2010-11-13 11:55:17 +0100 | [diff] [blame] | 356 | blkdev_put(d->dm_dev.bdev, d->dm_dev.mode | FMODE_EXCL); |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 357 | d->dm_dev.bdev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | } |
| 359 | |
| 360 | /* |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 361 | * If possible, this checks an area of a destination device is invalid. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | */ |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 363 | static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev, |
| 364 | sector_t start, sector_t len, void *data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | { |
Milan Broz | f4808ca | 2011-05-29 13:02:52 +0100 | [diff] [blame] | 366 | struct request_queue *q; |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 367 | struct queue_limits *limits = data; |
| 368 | struct block_device *bdev = dev->bdev; |
| 369 | sector_t dev_size = |
| 370 | i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 371 | unsigned short logical_block_size_sectors = |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 372 | limits->logical_block_size >> SECTOR_SHIFT; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 373 | char b[BDEVNAME_SIZE]; |
Mike Anderson | 2cd54d9 | 2007-05-09 02:32:57 -0700 | [diff] [blame] | 374 | |
Milan Broz | f4808ca | 2011-05-29 13:02:52 +0100 | [diff] [blame] | 375 | /* |
| 376 | * Some devices exist without request functions, |
| 377 | * such as loop devices not yet bound to backing files. |
| 378 | * Forbid the use of such devices. |
| 379 | */ |
| 380 | q = bdev_get_queue(bdev); |
| 381 | if (!q || !q->make_request_fn) { |
| 382 | DMWARN("%s: %s is not yet initialised: " |
| 383 | "start=%llu, len=%llu, dev_size=%llu", |
| 384 | dm_device_name(ti->table->md), bdevname(bdev, b), |
| 385 | (unsigned long long)start, |
| 386 | (unsigned long long)len, |
| 387 | (unsigned long long)dev_size); |
| 388 | return 1; |
| 389 | } |
| 390 | |
Mike Anderson | 2cd54d9 | 2007-05-09 02:32:57 -0700 | [diff] [blame] | 391 | if (!dev_size) |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 392 | return 0; |
Mike Anderson | 2cd54d9 | 2007-05-09 02:32:57 -0700 | [diff] [blame] | 393 | |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 394 | if ((start >= dev_size) || (start + len > dev_size)) { |
Mike Snitzer | a963a95 | 2009-09-04 20:40:24 +0100 | [diff] [blame] | 395 | DMWARN("%s: %s too small for target: " |
| 396 | "start=%llu, len=%llu, dev_size=%llu", |
| 397 | dm_device_name(ti->table->md), bdevname(bdev, b), |
| 398 | (unsigned long long)start, |
| 399 | (unsigned long long)len, |
| 400 | (unsigned long long)dev_size); |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 401 | return 1; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 402 | } |
| 403 | |
| 404 | if (logical_block_size_sectors <= 1) |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 405 | return 0; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 406 | |
| 407 | if (start & (logical_block_size_sectors - 1)) { |
| 408 | DMWARN("%s: start=%llu not aligned to h/w " |
Mike Snitzer | a963a95 | 2009-09-04 20:40:24 +0100 | [diff] [blame] | 409 | "logical block size %u of %s", |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 410 | dm_device_name(ti->table->md), |
| 411 | (unsigned long long)start, |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 412 | limits->logical_block_size, bdevname(bdev, b)); |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 413 | return 1; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 414 | } |
| 415 | |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 416 | if (len & (logical_block_size_sectors - 1)) { |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 417 | DMWARN("%s: len=%llu not aligned to h/w " |
Mike Snitzer | a963a95 | 2009-09-04 20:40:24 +0100 | [diff] [blame] | 418 | "logical block size %u of %s", |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 419 | dm_device_name(ti->table->md), |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 420 | (unsigned long long)len, |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 421 | limits->logical_block_size, bdevname(bdev, b)); |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 422 | return 1; |
Mike Snitzer | 02acc3a | 2009-06-22 10:12:30 +0100 | [diff] [blame] | 423 | } |
| 424 | |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 425 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | } |
| 427 | |
| 428 | /* |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 429 | * This upgrades the mode on an already open dm_dev, being |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | * careful to leave things as they were if we fail to reopen the |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 431 | * device and not to touch the existing bdev field in case |
| 432 | * it is accessed concurrently inside dm_table_any_congested(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | */ |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 434 | static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode, |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 435 | struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 436 | { |
| 437 | int r; |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 438 | struct dm_dev_internal dd_new, dd_old; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 440 | dd_new = dd_old = *dd; |
| 441 | |
| 442 | dd_new.dm_dev.mode |= new_mode; |
| 443 | dd_new.dm_dev.bdev = NULL; |
| 444 | |
| 445 | r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md); |
| 446 | if (r) |
| 447 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 449 | dd->dm_dev.mode |= new_mode; |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 450 | close_dev(&dd_old, md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 452 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | } |
| 454 | |
| 455 | /* |
| 456 | * Add a device to the list, or just increment the usage count if |
| 457 | * it's already present. |
| 458 | */ |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 459 | int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, |
| 460 | struct dm_dev **result) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | { |
| 462 | int r; |
Andrew Morton | 69a2ce7 | 2008-02-08 02:10:14 +0000 | [diff] [blame] | 463 | dev_t uninitialized_var(dev); |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 464 | struct dm_dev_internal *dd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | unsigned int major, minor; |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 466 | struct dm_table *t = ti->table; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | |
Eric Sesterhenn | 547bc92 | 2006-03-26 18:22:50 +0200 | [diff] [blame] | 468 | BUG_ON(!t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 469 | |
| 470 | if (sscanf(path, "%u:%u", &major, &minor) == 2) { |
| 471 | /* Extract the major/minor numbers */ |
| 472 | dev = MKDEV(major, minor); |
| 473 | if (MAJOR(dev) != major || MINOR(dev) != minor) |
| 474 | return -EOVERFLOW; |
| 475 | } else { |
| 476 | /* convert the path to a device */ |
Christoph Hellwig | 72e8264 | 2008-08-11 00:24:08 +0200 | [diff] [blame] | 477 | struct block_device *bdev = lookup_bdev(path); |
| 478 | |
| 479 | if (IS_ERR(bdev)) |
| 480 | return PTR_ERR(bdev); |
| 481 | dev = bdev->bd_dev; |
| 482 | bdput(bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | } |
| 484 | |
| 485 | dd = find_device(&t->devices, dev); |
| 486 | if (!dd) { |
| 487 | dd = kmalloc(sizeof(*dd), GFP_KERNEL); |
| 488 | if (!dd) |
| 489 | return -ENOMEM; |
| 490 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 491 | dd->dm_dev.mode = mode; |
| 492 | dd->dm_dev.bdev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 493 | |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 494 | if ((r = open_dev(dd, dev, t->md))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | kfree(dd); |
| 496 | return r; |
| 497 | } |
| 498 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 499 | format_dev_t(dd->dm_dev.name, dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 500 | |
| 501 | atomic_set(&dd->count, 0); |
| 502 | list_add(&dd->list, &t->devices); |
| 503 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 504 | } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) { |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 505 | r = upgrade_mode(dd, mode, t->md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | if (r) |
| 507 | return r; |
| 508 | } |
| 509 | atomic_inc(&dd->count); |
| 510 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 511 | *result = &dd->dm_dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | return 0; |
| 513 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 514 | EXPORT_SYMBOL(dm_get_device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 516 | int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev, |
Mike Snitzer | 5dea271 | 2009-07-23 20:30:42 +0100 | [diff] [blame] | 517 | sector_t start, sector_t len, void *data) |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 518 | { |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 519 | struct queue_limits *limits = data; |
| 520 | struct block_device *bdev = dev->bdev; |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 521 | struct request_queue *q = bdev_get_queue(bdev); |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 522 | char b[BDEVNAME_SIZE]; |
| 523 | |
| 524 | if (unlikely(!q)) { |
| 525 | DMWARN("%s: Cannot set limits for nonexistent device %s", |
| 526 | dm_device_name(ti->table->md), bdevname(bdev, b)); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 527 | return 0; |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 528 | } |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 529 | |
Martin K. Petersen | b27d7f1 | 2010-01-11 03:21:50 -0500 | [diff] [blame] | 530 | if (bdev_stack_limits(limits, bdev, start) < 0) |
| 531 | DMWARN("%s: adding target device %s caused an alignment inconsistency: " |
Mike Snitzer | a963a95 | 2009-09-04 20:40:24 +0100 | [diff] [blame] | 532 | "physical_block_size=%u, logical_block_size=%u, " |
| 533 | "alignment_offset=%u, start=%llu", |
| 534 | dm_device_name(ti->table->md), bdevname(bdev, b), |
| 535 | q->limits.physical_block_size, |
| 536 | q->limits.logical_block_size, |
| 537 | q->limits.alignment_offset, |
Martin K. Petersen | b27d7f1 | 2010-01-11 03:21:50 -0500 | [diff] [blame] | 538 | (unsigned long long) start << SECTOR_SHIFT); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 539 | |
Milan Broz | 9980c63 | 2008-07-21 12:00:39 +0100 | [diff] [blame] | 540 | /* |
| 541 | * Check if merge fn is supported. |
| 542 | * If not we'll force DM to use PAGE_SIZE or |
| 543 | * smaller I/O, just to be safe. |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 544 | */ |
Mikulas Patocka | d5b9dd0 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 545 | if (dm_queue_merge_is_compulsory(q) && !ti->type->merge) |
Mike Snitzer | 72d4cd9 | 2010-12-17 08:34:20 +0100 | [diff] [blame] | 546 | blk_limits_max_hw_sectors(limits, |
| 547 | (unsigned int) (PAGE_SIZE >> 9)); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 548 | return 0; |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 549 | } |
| 550 | EXPORT_SYMBOL_GPL(dm_set_device_limits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | /* |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 553 | * Decrement a device's use count and remove it if necessary. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 555 | void dm_put_device(struct dm_target *ti, struct dm_dev *d) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 556 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 557 | struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal, |
| 558 | dm_dev); |
| 559 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | if (atomic_dec_and_test(&dd->count)) { |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 561 | close_dev(dd, ti->table->md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | list_del(&dd->list); |
| 563 | kfree(dd); |
| 564 | } |
| 565 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 566 | EXPORT_SYMBOL(dm_put_device); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | |
| 568 | /* |
| 569 | * Checks to see if the target joins onto the end of the table. |
| 570 | */ |
| 571 | static int adjoin(struct dm_table *table, struct dm_target *ti) |
| 572 | { |
| 573 | struct dm_target *prev; |
| 574 | |
| 575 | if (!table->num_targets) |
| 576 | return !ti->begin; |
| 577 | |
| 578 | prev = &table->targets[table->num_targets - 1]; |
| 579 | return (ti->begin == (prev->begin + prev->len)); |
| 580 | } |
| 581 | |
| 582 | /* |
| 583 | * Used to dynamically allocate the arg array. |
| 584 | */ |
| 585 | static char **realloc_argv(unsigned *array_size, char **old_argv) |
| 586 | { |
| 587 | char **argv; |
| 588 | unsigned new_size; |
| 589 | |
| 590 | new_size = *array_size ? *array_size * 2 : 64; |
| 591 | argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL); |
| 592 | if (argv) { |
| 593 | memcpy(argv, old_argv, *array_size * sizeof(*argv)); |
| 594 | *array_size = new_size; |
| 595 | } |
| 596 | |
| 597 | kfree(old_argv); |
| 598 | return argv; |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * Destructively splits up the argument list to pass to ctr. |
| 603 | */ |
| 604 | int dm_split_args(int *argc, char ***argvp, char *input) |
| 605 | { |
| 606 | char *start, *end = input, *out, **argv = NULL; |
| 607 | unsigned array_size = 0; |
| 608 | |
| 609 | *argc = 0; |
David Teigland | 814d686 | 2006-06-26 00:27:31 -0700 | [diff] [blame] | 610 | |
| 611 | if (!input) { |
| 612 | *argvp = NULL; |
| 613 | return 0; |
| 614 | } |
| 615 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | argv = realloc_argv(&array_size, argv); |
| 617 | if (!argv) |
| 618 | return -ENOMEM; |
| 619 | |
| 620 | while (1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 621 | /* Skip whitespace */ |
André Goddard Rosa | e7d2860 | 2009-12-14 18:01:06 -0800 | [diff] [blame] | 622 | start = skip_spaces(end); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | |
| 624 | if (!*start) |
| 625 | break; /* success, we hit the end */ |
| 626 | |
| 627 | /* 'out' is used to remove any back-quotes */ |
| 628 | end = out = start; |
| 629 | while (*end) { |
| 630 | /* Everything apart from '\0' can be quoted */ |
| 631 | if (*end == '\\' && *(end + 1)) { |
| 632 | *out++ = *(end + 1); |
| 633 | end += 2; |
| 634 | continue; |
| 635 | } |
| 636 | |
| 637 | if (isspace(*end)) |
| 638 | break; /* end of token */ |
| 639 | |
| 640 | *out++ = *end++; |
| 641 | } |
| 642 | |
| 643 | /* have we already filled the array ? */ |
| 644 | if ((*argc + 1) > array_size) { |
| 645 | argv = realloc_argv(&array_size, argv); |
| 646 | if (!argv) |
| 647 | return -ENOMEM; |
| 648 | } |
| 649 | |
| 650 | /* we know this is whitespace */ |
| 651 | if (*end) |
| 652 | end++; |
| 653 | |
| 654 | /* terminate the string and put it in the array */ |
| 655 | *out = '\0'; |
| 656 | argv[*argc] = start; |
| 657 | (*argc)++; |
| 658 | } |
| 659 | |
| 660 | *argvp = argv; |
| 661 | return 0; |
| 662 | } |
| 663 | |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 664 | /* |
| 665 | * Impose necessary and sufficient conditions on a devices's table such |
| 666 | * that any incoming bio which respects its logical_block_size can be |
| 667 | * processed successfully. If it falls across the boundary between |
| 668 | * two or more targets, the size of each piece it gets split into must |
| 669 | * be compatible with the logical_block_size of the target processing it. |
| 670 | */ |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 671 | static int validate_hardware_logical_block_alignment(struct dm_table *table, |
| 672 | struct queue_limits *limits) |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 673 | { |
| 674 | /* |
| 675 | * This function uses arithmetic modulo the logical_block_size |
| 676 | * (in units of 512-byte sectors). |
| 677 | */ |
| 678 | unsigned short device_logical_block_size_sects = |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 679 | limits->logical_block_size >> SECTOR_SHIFT; |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 680 | |
| 681 | /* |
| 682 | * Offset of the start of the next table entry, mod logical_block_size. |
| 683 | */ |
| 684 | unsigned short next_target_start = 0; |
| 685 | |
| 686 | /* |
| 687 | * Given an aligned bio that extends beyond the end of a |
| 688 | * target, how many sectors must the next target handle? |
| 689 | */ |
| 690 | unsigned short remaining = 0; |
| 691 | |
| 692 | struct dm_target *uninitialized_var(ti); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 693 | struct queue_limits ti_limits; |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 694 | unsigned i = 0; |
| 695 | |
| 696 | /* |
| 697 | * Check each entry in the table in turn. |
| 698 | */ |
| 699 | while (i < dm_table_get_num_targets(table)) { |
| 700 | ti = dm_table_get_target(table, i++); |
| 701 | |
Martin K. Petersen | b1bd055 | 2012-01-11 16:27:11 +0100 | [diff] [blame] | 702 | blk_set_stacking_limits(&ti_limits); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 703 | |
| 704 | /* combine all target devices' limits */ |
| 705 | if (ti->type->iterate_devices) |
| 706 | ti->type->iterate_devices(ti, dm_set_device_limits, |
| 707 | &ti_limits); |
| 708 | |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 709 | /* |
| 710 | * If the remaining sectors fall entirely within this |
| 711 | * table entry are they compatible with its logical_block_size? |
| 712 | */ |
| 713 | if (remaining < ti->len && |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 714 | remaining & ((ti_limits.logical_block_size >> |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 715 | SECTOR_SHIFT) - 1)) |
| 716 | break; /* Error */ |
| 717 | |
| 718 | next_target_start = |
| 719 | (unsigned short) ((next_target_start + ti->len) & |
| 720 | (device_logical_block_size_sects - 1)); |
| 721 | remaining = next_target_start ? |
| 722 | device_logical_block_size_sects - next_target_start : 0; |
| 723 | } |
| 724 | |
| 725 | if (remaining) { |
| 726 | DMWARN("%s: table line %u (start sect %llu len %llu) " |
Mike Snitzer | a963a95 | 2009-09-04 20:40:24 +0100 | [diff] [blame] | 727 | "not aligned to h/w logical block size %u", |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 728 | dm_device_name(table->md), i, |
| 729 | (unsigned long long) ti->begin, |
| 730 | (unsigned long long) ti->len, |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 731 | limits->logical_block_size); |
Mike Snitzer | be6d430 | 2009-06-22 10:12:31 +0100 | [diff] [blame] | 732 | return -EINVAL; |
| 733 | } |
| 734 | |
| 735 | return 0; |
| 736 | } |
| 737 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | int dm_table_add_target(struct dm_table *t, const char *type, |
| 739 | sector_t start, sector_t len, char *params) |
| 740 | { |
| 741 | int r = -EINVAL, argc; |
| 742 | char **argv; |
| 743 | struct dm_target *tgt; |
| 744 | |
Alasdair G Kergon | 3791e2f | 2011-10-31 20:19:00 +0000 | [diff] [blame] | 745 | if (t->singleton) { |
| 746 | DMERR("%s: target type %s must appear alone in table", |
| 747 | dm_device_name(t->md), t->targets->type->name); |
| 748 | return -EINVAL; |
| 749 | } |
| 750 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 751 | if ((r = check_space(t))) |
| 752 | return r; |
| 753 | |
| 754 | tgt = t->targets + t->num_targets; |
| 755 | memset(tgt, 0, sizeof(*tgt)); |
| 756 | |
| 757 | if (!len) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 758 | DMERR("%s: zero-length target", dm_device_name(t->md)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | return -EINVAL; |
| 760 | } |
| 761 | |
| 762 | tgt->type = dm_get_target_type(type); |
| 763 | if (!tgt->type) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 764 | DMERR("%s: %s: unknown target type", dm_device_name(t->md), |
| 765 | type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | return -EINVAL; |
| 767 | } |
| 768 | |
Alasdair G Kergon | 3791e2f | 2011-10-31 20:19:00 +0000 | [diff] [blame] | 769 | if (dm_target_needs_singleton(tgt->type)) { |
| 770 | if (t->num_targets) { |
| 771 | DMERR("%s: target type %s must appear alone in table", |
| 772 | dm_device_name(t->md), type); |
| 773 | return -EINVAL; |
| 774 | } |
| 775 | t->singleton = 1; |
| 776 | } |
| 777 | |
Alasdair G Kergon | cc6cbe1 | 2011-10-31 20:19:02 +0000 | [diff] [blame] | 778 | if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) { |
| 779 | DMERR("%s: target type %s may not be included in read-only tables", |
| 780 | dm_device_name(t->md), type); |
| 781 | return -EINVAL; |
| 782 | } |
| 783 | |
Alasdair G Kergon | 36a0456 | 2011-10-31 20:19:04 +0000 | [diff] [blame] | 784 | if (t->immutable_target_type) { |
| 785 | if (t->immutable_target_type != tgt->type) { |
| 786 | DMERR("%s: immutable target type %s cannot be mixed with other target types", |
| 787 | dm_device_name(t->md), t->immutable_target_type->name); |
| 788 | return -EINVAL; |
| 789 | } |
| 790 | } else if (dm_target_is_immutable(tgt->type)) { |
| 791 | if (t->num_targets) { |
| 792 | DMERR("%s: immutable target type %s cannot be mixed with other target types", |
| 793 | dm_device_name(t->md), tgt->type->name); |
| 794 | return -EINVAL; |
| 795 | } |
| 796 | t->immutable_target_type = tgt->type; |
| 797 | } |
| 798 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 799 | tgt->table = t; |
| 800 | tgt->begin = start; |
| 801 | tgt->len = len; |
| 802 | tgt->error = "Unknown error"; |
| 803 | |
| 804 | /* |
| 805 | * Does this target adjoin the previous one ? |
| 806 | */ |
| 807 | if (!adjoin(t, tgt)) { |
| 808 | tgt->error = "Gap in table"; |
| 809 | r = -EINVAL; |
| 810 | goto bad; |
| 811 | } |
| 812 | |
| 813 | r = dm_split_args(&argc, &argv, params); |
| 814 | if (r) { |
| 815 | tgt->error = "couldn't split parameters (insufficient memory)"; |
| 816 | goto bad; |
| 817 | } |
| 818 | |
| 819 | r = tgt->type->ctr(tgt, argc, argv); |
| 820 | kfree(argv); |
| 821 | if (r) |
| 822 | goto bad; |
| 823 | |
| 824 | t->highs[t->num_targets++] = tgt->begin + tgt->len - 1; |
| 825 | |
Mike Snitzer | 936688d | 2011-08-02 12:32:01 +0100 | [diff] [blame] | 826 | if (!tgt->num_discard_requests && tgt->discards_supported) |
| 827 | DMWARN("%s: %s: ignoring discards_supported because num_discard_requests is zero.", |
| 828 | dm_device_name(t->md), type); |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 829 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 830 | return 0; |
| 831 | |
| 832 | bad: |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 833 | DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 834 | dm_put_target_type(tgt->type); |
| 835 | return r; |
| 836 | } |
| 837 | |
Mike Snitzer | 498f010 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 838 | /* |
| 839 | * Target argument parsing helpers. |
| 840 | */ |
| 841 | static int validate_next_arg(struct dm_arg *arg, struct dm_arg_set *arg_set, |
| 842 | unsigned *value, char **error, unsigned grouped) |
| 843 | { |
| 844 | const char *arg_str = dm_shift_arg(arg_set); |
| 845 | |
| 846 | if (!arg_str || |
| 847 | (sscanf(arg_str, "%u", value) != 1) || |
| 848 | (*value < arg->min) || |
| 849 | (*value > arg->max) || |
| 850 | (grouped && arg_set->argc < *value)) { |
| 851 | *error = arg->error; |
| 852 | return -EINVAL; |
| 853 | } |
| 854 | |
| 855 | return 0; |
| 856 | } |
| 857 | |
| 858 | int dm_read_arg(struct dm_arg *arg, struct dm_arg_set *arg_set, |
| 859 | unsigned *value, char **error) |
| 860 | { |
| 861 | return validate_next_arg(arg, arg_set, value, error, 0); |
| 862 | } |
| 863 | EXPORT_SYMBOL(dm_read_arg); |
| 864 | |
| 865 | int dm_read_arg_group(struct dm_arg *arg, struct dm_arg_set *arg_set, |
| 866 | unsigned *value, char **error) |
| 867 | { |
| 868 | return validate_next_arg(arg, arg_set, value, error, 1); |
| 869 | } |
| 870 | EXPORT_SYMBOL(dm_read_arg_group); |
| 871 | |
| 872 | const char *dm_shift_arg(struct dm_arg_set *as) |
| 873 | { |
| 874 | char *r; |
| 875 | |
| 876 | if (as->argc) { |
| 877 | as->argc--; |
| 878 | r = *as->argv; |
| 879 | as->argv++; |
| 880 | return r; |
| 881 | } |
| 882 | |
| 883 | return NULL; |
| 884 | } |
| 885 | EXPORT_SYMBOL(dm_shift_arg); |
| 886 | |
| 887 | void dm_consume_args(struct dm_arg_set *as, unsigned num_args) |
| 888 | { |
| 889 | BUG_ON(as->argc < num_args); |
| 890 | as->argc -= num_args; |
| 891 | as->argv += num_args; |
| 892 | } |
| 893 | EXPORT_SYMBOL(dm_consume_args); |
| 894 | |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 895 | static int dm_table_set_type(struct dm_table *t) |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 896 | { |
| 897 | unsigned i; |
| 898 | unsigned bio_based = 0, request_based = 0; |
| 899 | struct dm_target *tgt; |
| 900 | struct dm_dev_internal *dd; |
| 901 | struct list_head *devices; |
| 902 | |
| 903 | for (i = 0; i < t->num_targets; i++) { |
| 904 | tgt = t->targets + i; |
| 905 | if (dm_target_request_based(tgt)) |
| 906 | request_based = 1; |
| 907 | else |
| 908 | bio_based = 1; |
| 909 | |
| 910 | if (bio_based && request_based) { |
| 911 | DMWARN("Inconsistent table: different target types" |
| 912 | " can't be mixed up"); |
| 913 | return -EINVAL; |
| 914 | } |
| 915 | } |
| 916 | |
| 917 | if (bio_based) { |
| 918 | /* We must use this table as bio-based */ |
| 919 | t->type = DM_TYPE_BIO_BASED; |
| 920 | return 0; |
| 921 | } |
| 922 | |
| 923 | BUG_ON(!request_based); /* No targets in this table */ |
| 924 | |
| 925 | /* Non-request-stackable devices can't be used for request-based dm */ |
| 926 | devices = dm_table_get_devices(t); |
| 927 | list_for_each_entry(dd, devices, list) { |
| 928 | if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) { |
| 929 | DMWARN("table load rejected: including" |
| 930 | " non-request-stackable devices"); |
| 931 | return -EINVAL; |
| 932 | } |
| 933 | } |
| 934 | |
| 935 | /* |
| 936 | * Request-based dm supports only tables that have a single target now. |
| 937 | * To support multiple targets, request splitting support is needed, |
| 938 | * and that needs lots of changes in the block-layer. |
| 939 | * (e.g. request completion process for partial completion.) |
| 940 | */ |
| 941 | if (t->num_targets > 1) { |
| 942 | DMWARN("Request-based dm doesn't support multiple targets yet"); |
| 943 | return -EINVAL; |
| 944 | } |
| 945 | |
| 946 | t->type = DM_TYPE_REQUEST_BASED; |
| 947 | |
| 948 | return 0; |
| 949 | } |
| 950 | |
| 951 | unsigned dm_table_get_type(struct dm_table *t) |
| 952 | { |
| 953 | return t->type; |
| 954 | } |
| 955 | |
Alasdair G Kergon | 36a0456 | 2011-10-31 20:19:04 +0000 | [diff] [blame] | 956 | struct target_type *dm_table_get_immutable_target_type(struct dm_table *t) |
| 957 | { |
| 958 | return t->immutable_target_type; |
| 959 | } |
| 960 | |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 961 | bool dm_table_request_based(struct dm_table *t) |
| 962 | { |
| 963 | return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED; |
| 964 | } |
| 965 | |
| 966 | int dm_table_alloc_md_mempools(struct dm_table *t) |
| 967 | { |
| 968 | unsigned type = dm_table_get_type(t); |
| 969 | |
| 970 | if (unlikely(type == DM_TYPE_NONE)) { |
| 971 | DMWARN("no table type is set, can't allocate mempools"); |
| 972 | return -EINVAL; |
| 973 | } |
| 974 | |
Martin K. Petersen | a91a278 | 2011-03-17 11:11:05 +0100 | [diff] [blame] | 975 | t->mempools = dm_alloc_md_mempools(type, t->integrity_supported); |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 976 | if (!t->mempools) |
| 977 | return -ENOMEM; |
| 978 | |
| 979 | return 0; |
| 980 | } |
| 981 | |
| 982 | void dm_table_free_md_mempools(struct dm_table *t) |
| 983 | { |
| 984 | dm_free_md_mempools(t->mempools); |
| 985 | t->mempools = NULL; |
| 986 | } |
| 987 | |
| 988 | struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t) |
| 989 | { |
| 990 | return t->mempools; |
| 991 | } |
| 992 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 993 | static int setup_indexes(struct dm_table *t) |
| 994 | { |
| 995 | int i; |
| 996 | unsigned int total = 0; |
| 997 | sector_t *indexes; |
| 998 | |
| 999 | /* allocate the space for *all* the indexes */ |
| 1000 | for (i = t->depth - 2; i >= 0; i--) { |
| 1001 | t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE); |
| 1002 | total += t->counts[i]; |
| 1003 | } |
| 1004 | |
| 1005 | indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE); |
| 1006 | if (!indexes) |
| 1007 | return -ENOMEM; |
| 1008 | |
| 1009 | /* set up internal nodes, bottom-up */ |
Jun'ichi Nomura | 82d601d | 2008-02-08 02:10:04 +0000 | [diff] [blame] | 1010 | for (i = t->depth - 2; i >= 0; i--) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | t->index[i] = indexes; |
| 1012 | indexes += (KEYS_PER_NODE * t->counts[i]); |
| 1013 | setup_btree_index(i, t); |
| 1014 | } |
| 1015 | |
| 1016 | return 0; |
| 1017 | } |
| 1018 | |
| 1019 | /* |
| 1020 | * Builds the btree to index the map. |
| 1021 | */ |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1022 | static int dm_table_build_index(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1023 | { |
| 1024 | int r = 0; |
| 1025 | unsigned int leaf_nodes; |
| 1026 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1027 | /* how many indexes will the btree have ? */ |
| 1028 | leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE); |
| 1029 | t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE); |
| 1030 | |
| 1031 | /* leaf layer has already been set up */ |
| 1032 | t->counts[t->depth - 1] = leaf_nodes; |
| 1033 | t->index[t->depth - 1] = t->highs; |
| 1034 | |
| 1035 | if (t->depth >= 2) |
| 1036 | r = setup_indexes(t); |
| 1037 | |
| 1038 | return r; |
| 1039 | } |
| 1040 | |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1041 | /* |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1042 | * Get a disk whose integrity profile reflects the table's profile. |
| 1043 | * If %match_all is true, all devices' profiles must match. |
| 1044 | * If %match_all is false, all devices must at least have an |
| 1045 | * allocated integrity profile; but uninitialized is ok. |
| 1046 | * Returns NULL if integrity support was inconsistent or unavailable. |
| 1047 | */ |
| 1048 | static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t, |
| 1049 | bool match_all) |
| 1050 | { |
| 1051 | struct list_head *devices = dm_table_get_devices(t); |
| 1052 | struct dm_dev_internal *dd = NULL; |
| 1053 | struct gendisk *prev_disk = NULL, *template_disk = NULL; |
| 1054 | |
| 1055 | list_for_each_entry(dd, devices, list) { |
| 1056 | template_disk = dd->dm_dev.bdev->bd_disk; |
| 1057 | if (!blk_get_integrity(template_disk)) |
| 1058 | goto no_integrity; |
| 1059 | if (!match_all && !blk_integrity_is_initialized(template_disk)) |
| 1060 | continue; /* skip uninitialized profiles */ |
| 1061 | else if (prev_disk && |
| 1062 | blk_integrity_compare(prev_disk, template_disk) < 0) |
| 1063 | goto no_integrity; |
| 1064 | prev_disk = template_disk; |
| 1065 | } |
| 1066 | |
| 1067 | return template_disk; |
| 1068 | |
| 1069 | no_integrity: |
| 1070 | if (prev_disk) |
| 1071 | DMWARN("%s: integrity not set: %s and %s profile mismatch", |
| 1072 | dm_device_name(t->md), |
| 1073 | prev_disk->disk_name, |
| 1074 | template_disk->disk_name); |
| 1075 | return NULL; |
| 1076 | } |
| 1077 | |
| 1078 | /* |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1079 | * Register the mapped device for blk_integrity support if |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1080 | * the underlying devices have an integrity profile. But all devices |
| 1081 | * may not have matching profiles (checking all devices isn't reliable |
| 1082 | * during table load because this table may use other DM device(s) which |
| 1083 | * must be resumed before they will have an initialized integity profile). |
| 1084 | * Stacked DM devices force a 2 stage integrity profile validation: |
| 1085 | * 1 - during load, validate all initialized integrity profiles match |
| 1086 | * 2 - during resume, validate all integrity profiles match |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1087 | */ |
| 1088 | static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md) |
| 1089 | { |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1090 | struct gendisk *template_disk = NULL; |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1091 | |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1092 | template_disk = dm_table_get_integrity_disk(t, false); |
| 1093 | if (!template_disk) |
| 1094 | return 0; |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1095 | |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1096 | if (!blk_integrity_is_initialized(dm_disk(md))) { |
| 1097 | t->integrity_supported = 1; |
| 1098 | return blk_integrity_register(dm_disk(md), NULL); |
| 1099 | } |
| 1100 | |
| 1101 | /* |
| 1102 | * If DM device already has an initalized integrity |
| 1103 | * profile the new profile should not conflict. |
| 1104 | */ |
| 1105 | if (blk_integrity_is_initialized(template_disk) && |
| 1106 | blk_integrity_compare(dm_disk(md), template_disk) < 0) { |
| 1107 | DMWARN("%s: conflict with existing integrity profile: " |
| 1108 | "%s profile mismatch", |
| 1109 | dm_device_name(t->md), |
| 1110 | template_disk->disk_name); |
| 1111 | return 1; |
| 1112 | } |
| 1113 | |
| 1114 | /* Preserve existing initialized integrity profile */ |
| 1115 | t->integrity_supported = 1; |
Will Drewry | 26803b9 | 2010-08-12 04:14:03 +0100 | [diff] [blame] | 1116 | return 0; |
| 1117 | } |
| 1118 | |
| 1119 | /* |
| 1120 | * Prepares the table for use by building the indices, |
| 1121 | * setting the type, and allocating mempools. |
| 1122 | */ |
| 1123 | int dm_table_complete(struct dm_table *t) |
| 1124 | { |
| 1125 | int r; |
| 1126 | |
| 1127 | r = dm_table_set_type(t); |
| 1128 | if (r) { |
| 1129 | DMERR("unable to set table type"); |
| 1130 | return r; |
| 1131 | } |
| 1132 | |
| 1133 | r = dm_table_build_index(t); |
| 1134 | if (r) { |
| 1135 | DMERR("unable to build btrees"); |
| 1136 | return r; |
| 1137 | } |
| 1138 | |
| 1139 | r = dm_table_prealloc_integrity(t, t->md); |
| 1140 | if (r) { |
| 1141 | DMERR("could not register integrity profile."); |
| 1142 | return r; |
| 1143 | } |
| 1144 | |
| 1145 | r = dm_table_alloc_md_mempools(t); |
| 1146 | if (r) |
| 1147 | DMERR("unable to allocate mempools"); |
| 1148 | |
| 1149 | return r; |
| 1150 | } |
| 1151 | |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 1152 | static DEFINE_MUTEX(_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1153 | void dm_table_event_callback(struct dm_table *t, |
| 1154 | void (*fn)(void *), void *context) |
| 1155 | { |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 1156 | mutex_lock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1157 | t->event_fn = fn; |
| 1158 | t->event_context = context; |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 1159 | mutex_unlock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1160 | } |
| 1161 | |
| 1162 | void dm_table_event(struct dm_table *t) |
| 1163 | { |
| 1164 | /* |
| 1165 | * You can no longer call dm_table_event() from interrupt |
| 1166 | * context, use a bottom half instead. |
| 1167 | */ |
| 1168 | BUG_ON(in_interrupt()); |
| 1169 | |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 1170 | mutex_lock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1171 | if (t->event_fn) |
| 1172 | t->event_fn(t->event_context); |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 1173 | mutex_unlock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1174 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 1175 | EXPORT_SYMBOL(dm_table_event); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1176 | |
| 1177 | sector_t dm_table_get_size(struct dm_table *t) |
| 1178 | { |
| 1179 | return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0; |
| 1180 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 1181 | EXPORT_SYMBOL(dm_table_get_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | |
| 1183 | struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index) |
| 1184 | { |
Milan Broz | 1435353 | 2006-06-26 00:27:27 -0700 | [diff] [blame] | 1185 | if (index >= t->num_targets) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1186 | return NULL; |
| 1187 | |
| 1188 | return t->targets + index; |
| 1189 | } |
| 1190 | |
| 1191 | /* |
| 1192 | * Search the btree for the correct target. |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 1193 | * |
| 1194 | * Caller should check returned pointer with dm_target_is_valid() |
| 1195 | * to trap I/O beyond end of device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1196 | */ |
| 1197 | struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) |
| 1198 | { |
| 1199 | unsigned int l, n = 0, k = 0; |
| 1200 | sector_t *node; |
| 1201 | |
| 1202 | for (l = 0; l < t->depth; l++) { |
| 1203 | n = get_child(n, k); |
| 1204 | node = get_node(t, l, n); |
| 1205 | |
| 1206 | for (k = 0; k < KEYS_PER_NODE; k++) |
| 1207 | if (node[k] >= sector) |
| 1208 | break; |
| 1209 | } |
| 1210 | |
| 1211 | return &t->targets[(KEYS_PER_NODE * n) + k]; |
| 1212 | } |
| 1213 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1214 | /* |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1215 | * Establish the new table's queue_limits and validate them. |
| 1216 | */ |
| 1217 | int dm_calculate_queue_limits(struct dm_table *table, |
| 1218 | struct queue_limits *limits) |
| 1219 | { |
| 1220 | struct dm_target *uninitialized_var(ti); |
| 1221 | struct queue_limits ti_limits; |
| 1222 | unsigned i = 0; |
| 1223 | |
Martin K. Petersen | b1bd055 | 2012-01-11 16:27:11 +0100 | [diff] [blame] | 1224 | blk_set_stacking_limits(limits); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1225 | |
| 1226 | while (i < dm_table_get_num_targets(table)) { |
Martin K. Petersen | b1bd055 | 2012-01-11 16:27:11 +0100 | [diff] [blame] | 1227 | blk_set_stacking_limits(&ti_limits); |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1228 | |
| 1229 | ti = dm_table_get_target(table, i++); |
| 1230 | |
| 1231 | if (!ti->type->iterate_devices) |
| 1232 | goto combine_limits; |
| 1233 | |
| 1234 | /* |
| 1235 | * Combine queue limits of all the devices this target uses. |
| 1236 | */ |
| 1237 | ti->type->iterate_devices(ti, dm_set_device_limits, |
| 1238 | &ti_limits); |
| 1239 | |
Mike Snitzer | 40bea43 | 2009-09-04 20:40:25 +0100 | [diff] [blame] | 1240 | /* Set I/O hints portion of queue limits */ |
| 1241 | if (ti->type->io_hints) |
| 1242 | ti->type->io_hints(ti, &ti_limits); |
| 1243 | |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1244 | /* |
| 1245 | * Check each device area is consistent with the target's |
| 1246 | * overall queue limits. |
| 1247 | */ |
Mikulas Patocka | f6a1ed1 | 2009-09-04 20:40:22 +0100 | [diff] [blame] | 1248 | if (ti->type->iterate_devices(ti, device_area_is_invalid, |
| 1249 | &ti_limits)) |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1250 | return -EINVAL; |
| 1251 | |
| 1252 | combine_limits: |
| 1253 | /* |
| 1254 | * Merge this target's queue limits into the overall limits |
| 1255 | * for the table. |
| 1256 | */ |
| 1257 | if (blk_stack_limits(limits, &ti_limits, 0) < 0) |
Martin K. Petersen | b27d7f1 | 2010-01-11 03:21:50 -0500 | [diff] [blame] | 1258 | DMWARN("%s: adding target device " |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1259 | "(start sect %llu len %llu) " |
Martin K. Petersen | b27d7f1 | 2010-01-11 03:21:50 -0500 | [diff] [blame] | 1260 | "caused an alignment inconsistency", |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1261 | dm_device_name(table->md), |
| 1262 | (unsigned long long) ti->begin, |
| 1263 | (unsigned long long) ti->len); |
| 1264 | } |
| 1265 | |
| 1266 | return validate_hardware_logical_block_alignment(table, limits); |
| 1267 | } |
| 1268 | |
| 1269 | /* |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1270 | * Set the integrity profile for this device if all devices used have |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1271 | * matching profiles. We're quite deep in the resume path but still |
| 1272 | * don't know if all devices (particularly DM devices this device |
| 1273 | * may be stacked on) have matching profiles. Even if the profiles |
| 1274 | * don't match we have no way to fail (to resume) at this point. |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1275 | */ |
| 1276 | static void dm_table_set_integrity(struct dm_table *t) |
| 1277 | { |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1278 | struct gendisk *template_disk = NULL; |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1279 | |
| 1280 | if (!blk_get_integrity(dm_disk(t->md))) |
| 1281 | return; |
| 1282 | |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1283 | template_disk = dm_table_get_integrity_disk(t, true); |
Mike Snitzer | 876fbba | 2011-09-25 23:26:17 +0100 | [diff] [blame] | 1284 | if (template_disk) |
| 1285 | blk_integrity_register(dm_disk(t->md), |
| 1286 | blk_get_integrity(template_disk)); |
| 1287 | else if (blk_integrity_is_initialized(dm_disk(t->md))) |
Mike Snitzer | a63a5cf | 2011-04-01 21:02:31 +0200 | [diff] [blame] | 1288 | DMWARN("%s: device no longer has a valid integrity profile", |
| 1289 | dm_device_name(t->md)); |
Mike Snitzer | 876fbba | 2011-09-25 23:26:17 +0100 | [diff] [blame] | 1290 | else |
| 1291 | DMWARN("%s: unable to establish an integrity profile", |
| 1292 | dm_device_name(t->md)); |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1293 | } |
| 1294 | |
Mike Snitzer | ed8b752 | 2011-08-02 12:32:08 +0100 | [diff] [blame] | 1295 | static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev, |
| 1296 | sector_t start, sector_t len, void *data) |
| 1297 | { |
| 1298 | unsigned flush = (*(unsigned *)data); |
| 1299 | struct request_queue *q = bdev_get_queue(dev->bdev); |
| 1300 | |
| 1301 | return q && (q->flush_flags & flush); |
| 1302 | } |
| 1303 | |
| 1304 | static bool dm_table_supports_flush(struct dm_table *t, unsigned flush) |
| 1305 | { |
| 1306 | struct dm_target *ti; |
| 1307 | unsigned i = 0; |
| 1308 | |
| 1309 | /* |
| 1310 | * Require at least one underlying device to support flushes. |
| 1311 | * t->devices includes internal dm devices such as mirror logs |
| 1312 | * so we need to use iterate_devices here, which targets |
| 1313 | * supporting flushes must provide. |
| 1314 | */ |
| 1315 | while (i < dm_table_get_num_targets(t)) { |
| 1316 | ti = dm_table_get_target(t, i++); |
| 1317 | |
| 1318 | if (!ti->num_flush_requests) |
| 1319 | continue; |
| 1320 | |
| 1321 | if (ti->type->iterate_devices && |
| 1322 | ti->type->iterate_devices(ti, device_flush_capable, &flush)) |
| 1323 | return 1; |
| 1324 | } |
| 1325 | |
| 1326 | return 0; |
| 1327 | } |
| 1328 | |
Milan Broz | 983c7db | 2011-09-25 23:26:21 +0100 | [diff] [blame] | 1329 | static bool dm_table_discard_zeroes_data(struct dm_table *t) |
| 1330 | { |
| 1331 | struct dm_target *ti; |
| 1332 | unsigned i = 0; |
| 1333 | |
| 1334 | /* Ensure that all targets supports discard_zeroes_data. */ |
| 1335 | while (i < dm_table_get_num_targets(t)) { |
| 1336 | ti = dm_table_get_target(t, i++); |
| 1337 | |
| 1338 | if (ti->discard_zeroes_data_unsupported) |
| 1339 | return 0; |
| 1340 | } |
| 1341 | |
| 1342 | return 1; |
| 1343 | } |
| 1344 | |
Mandeep Singh Baines | 4693c96 | 2011-10-31 20:18:50 +0000 | [diff] [blame] | 1345 | static int device_is_nonrot(struct dm_target *ti, struct dm_dev *dev, |
| 1346 | sector_t start, sector_t len, void *data) |
| 1347 | { |
| 1348 | struct request_queue *q = bdev_get_queue(dev->bdev); |
| 1349 | |
| 1350 | return q && blk_queue_nonrot(q); |
| 1351 | } |
| 1352 | |
| 1353 | static bool dm_table_is_nonrot(struct dm_table *t) |
| 1354 | { |
| 1355 | struct dm_target *ti; |
| 1356 | unsigned i = 0; |
| 1357 | |
| 1358 | /* Ensure that all underlying device are non-rotational. */ |
| 1359 | while (i < dm_table_get_num_targets(t)) { |
| 1360 | ti = dm_table_get_target(t, i++); |
| 1361 | |
| 1362 | if (!ti->type->iterate_devices || |
| 1363 | !ti->type->iterate_devices(ti, device_is_nonrot, NULL)) |
| 1364 | return 0; |
| 1365 | } |
| 1366 | |
| 1367 | return 1; |
| 1368 | } |
| 1369 | |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1370 | void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, |
| 1371 | struct queue_limits *limits) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1372 | { |
Mike Snitzer | ed8b752 | 2011-08-02 12:32:08 +0100 | [diff] [blame] | 1373 | unsigned flush = 0; |
| 1374 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1375 | /* |
Mike Snitzer | 1197764 | 2009-06-22 10:12:32 +0100 | [diff] [blame] | 1376 | * Copy table's limits to the DM device's request_queue |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1377 | */ |
Mike Snitzer | 754c5fc | 2009-06-22 10:12:34 +0100 | [diff] [blame] | 1378 | q->limits = *limits; |
Jens Axboe | c9a3f6d | 2008-04-29 19:12:35 +0200 | [diff] [blame] | 1379 | |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1380 | if (!dm_table_supports_discards(t)) |
| 1381 | queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q); |
| 1382 | else |
| 1383 | queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q); |
| 1384 | |
Mike Snitzer | ed8b752 | 2011-08-02 12:32:08 +0100 | [diff] [blame] | 1385 | if (dm_table_supports_flush(t, REQ_FLUSH)) { |
| 1386 | flush |= REQ_FLUSH; |
| 1387 | if (dm_table_supports_flush(t, REQ_FUA)) |
| 1388 | flush |= REQ_FUA; |
| 1389 | } |
| 1390 | blk_queue_flush(q, flush); |
| 1391 | |
Milan Broz | 983c7db | 2011-09-25 23:26:21 +0100 | [diff] [blame] | 1392 | if (!dm_table_discard_zeroes_data(t)) |
| 1393 | q->limits.discard_zeroes_data = 0; |
| 1394 | |
Mandeep Singh Baines | 4693c96 | 2011-10-31 20:18:50 +0000 | [diff] [blame] | 1395 | if (dm_table_is_nonrot(t)) |
| 1396 | queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q); |
| 1397 | else |
| 1398 | queue_flag_clear_unlocked(QUEUE_FLAG_NONROT, q); |
| 1399 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 1400 | dm_table_set_integrity(t); |
Kiyoshi Ueda | e6ee8c0 | 2009-06-22 10:12:36 +0100 | [diff] [blame] | 1401 | |
| 1402 | /* |
| 1403 | * QUEUE_FLAG_STACKABLE must be set after all queue settings are |
| 1404 | * visible to other CPUs because, once the flag is set, incoming bios |
| 1405 | * are processed by request-based dm, which refers to the queue |
| 1406 | * settings. |
| 1407 | * Until the flag set, bios are passed to bio-based dm and queued to |
| 1408 | * md->deferred where queue settings are not needed yet. |
| 1409 | * Those bios are passed to request-based dm at the resume time. |
| 1410 | */ |
| 1411 | smp_mb(); |
| 1412 | if (dm_table_request_based(t)) |
| 1413 | queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | } |
| 1415 | |
| 1416 | unsigned int dm_table_get_num_targets(struct dm_table *t) |
| 1417 | { |
| 1418 | return t->num_targets; |
| 1419 | } |
| 1420 | |
| 1421 | struct list_head *dm_table_get_devices(struct dm_table *t) |
| 1422 | { |
| 1423 | return &t->devices; |
| 1424 | } |
| 1425 | |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 1426 | fmode_t dm_table_get_mode(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1427 | { |
| 1428 | return t->mode; |
| 1429 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 1430 | EXPORT_SYMBOL(dm_table_get_mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1431 | |
| 1432 | static void suspend_targets(struct dm_table *t, unsigned postsuspend) |
| 1433 | { |
| 1434 | int i = t->num_targets; |
| 1435 | struct dm_target *ti = t->targets; |
| 1436 | |
| 1437 | while (i--) { |
| 1438 | if (postsuspend) { |
| 1439 | if (ti->type->postsuspend) |
| 1440 | ti->type->postsuspend(ti); |
| 1441 | } else if (ti->type->presuspend) |
| 1442 | ti->type->presuspend(ti); |
| 1443 | |
| 1444 | ti++; |
| 1445 | } |
| 1446 | } |
| 1447 | |
| 1448 | void dm_table_presuspend_targets(struct dm_table *t) |
| 1449 | { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1450 | if (!t) |
| 1451 | return; |
| 1452 | |
Adrian Bunk | e8488d0 | 2008-04-24 22:10:51 +0100 | [diff] [blame] | 1453 | suspend_targets(t, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1454 | } |
| 1455 | |
| 1456 | void dm_table_postsuspend_targets(struct dm_table *t) |
| 1457 | { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 1458 | if (!t) |
| 1459 | return; |
| 1460 | |
Adrian Bunk | e8488d0 | 2008-04-24 22:10:51 +0100 | [diff] [blame] | 1461 | suspend_targets(t, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1462 | } |
| 1463 | |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 1464 | int dm_table_resume_targets(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1465 | { |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 1466 | int i, r = 0; |
| 1467 | |
| 1468 | for (i = 0; i < t->num_targets; i++) { |
| 1469 | struct dm_target *ti = t->targets + i; |
| 1470 | |
| 1471 | if (!ti->type->preresume) |
| 1472 | continue; |
| 1473 | |
| 1474 | r = ti->type->preresume(ti); |
| 1475 | if (r) |
| 1476 | return r; |
| 1477 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1478 | |
| 1479 | for (i = 0; i < t->num_targets; i++) { |
| 1480 | struct dm_target *ti = t->targets + i; |
| 1481 | |
| 1482 | if (ti->type->resume) |
| 1483 | ti->type->resume(ti); |
| 1484 | } |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 1485 | |
| 1486 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1487 | } |
| 1488 | |
NeilBrown | 9d357b0 | 2011-01-13 20:00:01 +0000 | [diff] [blame] | 1489 | void dm_table_add_target_callbacks(struct dm_table *t, struct dm_target_callbacks *cb) |
| 1490 | { |
| 1491 | list_add(&cb->list, &t->target_callbacks); |
| 1492 | } |
| 1493 | EXPORT_SYMBOL_GPL(dm_table_add_target_callbacks); |
| 1494 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | int dm_table_any_congested(struct dm_table *t, int bdi_bits) |
| 1496 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1497 | struct dm_dev_internal *dd; |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1498 | struct list_head *devices = dm_table_get_devices(t); |
NeilBrown | 9d357b0 | 2011-01-13 20:00:01 +0000 | [diff] [blame] | 1499 | struct dm_target_callbacks *cb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1500 | int r = 0; |
| 1501 | |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1502 | list_for_each_entry(dd, devices, list) { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1503 | struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev); |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 1504 | char b[BDEVNAME_SIZE]; |
| 1505 | |
| 1506 | if (likely(q)) |
| 1507 | r |= bdi_congested(&q->backing_dev_info, bdi_bits); |
| 1508 | else |
| 1509 | DMWARN_LIMIT("%s: any_congested: nonexistent device %s", |
| 1510 | dm_device_name(t->md), |
| 1511 | bdevname(dd->dm_dev.bdev, b)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1512 | } |
| 1513 | |
NeilBrown | 9d357b0 | 2011-01-13 20:00:01 +0000 | [diff] [blame] | 1514 | list_for_each_entry(cb, &t->target_callbacks, list) |
| 1515 | if (cb->congested_fn) |
| 1516 | r |= cb->congested_fn(cb, bdi_bits); |
| 1517 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1518 | return r; |
| 1519 | } |
| 1520 | |
Kiyoshi Ueda | cec47e3 | 2009-06-22 10:12:35 +0100 | [diff] [blame] | 1521 | int dm_table_any_busy_target(struct dm_table *t) |
| 1522 | { |
| 1523 | unsigned i; |
| 1524 | struct dm_target *ti; |
| 1525 | |
| 1526 | for (i = 0; i < t->num_targets; i++) { |
| 1527 | ti = t->targets + i; |
| 1528 | if (ti->type->busy && ti->type->busy(ti)) |
| 1529 | return 1; |
| 1530 | } |
| 1531 | |
| 1532 | return 0; |
| 1533 | } |
| 1534 | |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1535 | struct mapped_device *dm_table_get_md(struct dm_table *t) |
| 1536 | { |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1537 | return t->md; |
| 1538 | } |
Mike Snitzer | 0864901 | 2011-08-02 12:32:04 +0100 | [diff] [blame] | 1539 | EXPORT_SYMBOL(dm_table_get_md); |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1540 | |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1541 | static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev, |
| 1542 | sector_t start, sector_t len, void *data) |
| 1543 | { |
| 1544 | struct request_queue *q = bdev_get_queue(dev->bdev); |
| 1545 | |
| 1546 | return q && blk_queue_discard(q); |
| 1547 | } |
| 1548 | |
| 1549 | bool dm_table_supports_discards(struct dm_table *t) |
| 1550 | { |
| 1551 | struct dm_target *ti; |
| 1552 | unsigned i = 0; |
| 1553 | |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1554 | /* |
Mike Snitzer | 4c25932 | 2011-05-29 12:52:55 +0100 | [diff] [blame] | 1555 | * Unless any target used by the table set discards_supported, |
| 1556 | * require at least one underlying device to support discards. |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1557 | * t->devices includes internal dm devices such as mirror logs |
| 1558 | * so we need to use iterate_devices here, which targets |
Mike Snitzer | 936688d | 2011-08-02 12:32:01 +0100 | [diff] [blame] | 1559 | * supporting discard selectively must provide. |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1560 | */ |
| 1561 | while (i < dm_table_get_num_targets(t)) { |
| 1562 | ti = dm_table_get_target(t, i++); |
| 1563 | |
Mike Snitzer | 936688d | 2011-08-02 12:32:01 +0100 | [diff] [blame] | 1564 | if (!ti->num_discard_requests) |
| 1565 | continue; |
| 1566 | |
Mike Snitzer | 4c25932 | 2011-05-29 12:52:55 +0100 | [diff] [blame] | 1567 | if (ti->discards_supported) |
| 1568 | return 1; |
| 1569 | |
Mike Snitzer | 5ae89a8 | 2010-08-12 04:14:08 +0100 | [diff] [blame] | 1570 | if (ti->type->iterate_devices && |
| 1571 | ti->type->iterate_devices(ti, device_discard_capable, NULL)) |
| 1572 | return 1; |
| 1573 | } |
| 1574 | |
| 1575 | return 0; |
| 1576 | } |