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> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/interrupt.h> |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 17 | #include <linux/mutex.h> |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 18 | #include <linux/delay.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include <asm/atomic.h> |
| 20 | |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 21 | #define DM_MSG_PREFIX "table" |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #define MAX_DEPTH 16 |
| 24 | #define NODE_SIZE L1_CACHE_BYTES |
| 25 | #define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t)) |
| 26 | #define CHILDREN_PER_NODE (KEYS_PER_NODE + 1) |
| 27 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 28 | /* |
| 29 | * The table has always exactly one reference from either mapped_device->map |
| 30 | * or hash_cell->new_map. This reference is not counted in table->holders. |
| 31 | * A pair of dm_create_table/dm_destroy_table functions is used for table |
| 32 | * creation/destruction. |
| 33 | * |
| 34 | * Temporary references from the other code increase table->holders. A pair |
| 35 | * of dm_table_get/dm_table_put functions is used to manipulate it. |
| 36 | * |
| 37 | * When the table is about to be destroyed, we wait for table->holders to |
| 38 | * drop to zero. |
| 39 | */ |
| 40 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | struct dm_table { |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 42 | struct mapped_device *md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | atomic_t holders; |
| 44 | |
| 45 | /* btree table */ |
| 46 | unsigned int depth; |
| 47 | unsigned int counts[MAX_DEPTH]; /* in nodes */ |
| 48 | sector_t *index[MAX_DEPTH]; |
| 49 | |
| 50 | unsigned int num_targets; |
| 51 | unsigned int num_allocated; |
| 52 | sector_t *highs; |
| 53 | struct dm_target *targets; |
| 54 | |
| 55 | /* |
| 56 | * Indicates the rw permissions for the new logical |
| 57 | * device. This should be a combination of FMODE_READ |
| 58 | * and FMODE_WRITE. |
| 59 | */ |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 60 | fmode_t mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | |
| 62 | /* a list of devices used by this table */ |
| 63 | struct list_head devices; |
| 64 | |
| 65 | /* |
| 66 | * These are optimistic limits taken from all the |
| 67 | * targets, some targets will need smaller limits. |
| 68 | */ |
| 69 | struct io_restrictions limits; |
| 70 | |
| 71 | /* events get handed up using this callback */ |
| 72 | void (*event_fn)(void *); |
| 73 | void *event_context; |
| 74 | }; |
| 75 | |
| 76 | /* |
| 77 | * Similar to ceiling(log_size(n)) |
| 78 | */ |
| 79 | static unsigned int int_log(unsigned int n, unsigned int base) |
| 80 | { |
| 81 | int result = 0; |
| 82 | |
| 83 | while (n > 1) { |
| 84 | n = dm_div_up(n, base); |
| 85 | result++; |
| 86 | } |
| 87 | |
| 88 | return result; |
| 89 | } |
| 90 | |
| 91 | /* |
| 92 | * Returns the minimum that is _not_ zero, unless both are zero. |
| 93 | */ |
| 94 | #define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r)) |
| 95 | |
| 96 | /* |
| 97 | * Combine two io_restrictions, always taking the lower value. |
| 98 | */ |
| 99 | static void combine_restrictions_low(struct io_restrictions *lhs, |
| 100 | struct io_restrictions *rhs) |
| 101 | { |
| 102 | lhs->max_sectors = |
| 103 | min_not_zero(lhs->max_sectors, rhs->max_sectors); |
| 104 | |
| 105 | lhs->max_phys_segments = |
| 106 | min_not_zero(lhs->max_phys_segments, rhs->max_phys_segments); |
| 107 | |
| 108 | lhs->max_hw_segments = |
| 109 | min_not_zero(lhs->max_hw_segments, rhs->max_hw_segments); |
| 110 | |
Martin K. Petersen | e1defc4 | 2009-05-22 17:17:49 -0400 | [diff] [blame] | 111 | lhs->logical_block_size = max(lhs->logical_block_size, |
| 112 | rhs->logical_block_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | |
| 114 | lhs->max_segment_size = |
| 115 | min_not_zero(lhs->max_segment_size, rhs->max_segment_size); |
| 116 | |
Neil Brown | 9121250 | 2007-12-13 14:16:04 +0000 | [diff] [blame] | 117 | lhs->max_hw_sectors = |
| 118 | min_not_zero(lhs->max_hw_sectors, rhs->max_hw_sectors); |
| 119 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | lhs->seg_boundary_mask = |
| 121 | min_not_zero(lhs->seg_boundary_mask, rhs->seg_boundary_mask); |
NeilBrown | 969429b | 2006-03-27 01:17:49 -0800 | [diff] [blame] | 122 | |
Vasily Averin | 5ec140e | 2007-10-31 08:33:24 +0100 | [diff] [blame] | 123 | lhs->bounce_pfn = min_not_zero(lhs->bounce_pfn, rhs->bounce_pfn); |
| 124 | |
NeilBrown | 969429b | 2006-03-27 01:17:49 -0800 | [diff] [blame] | 125 | lhs->no_cluster |= rhs->no_cluster; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | } |
| 127 | |
| 128 | /* |
| 129 | * Calculate the index of the child node of the n'th node k'th key. |
| 130 | */ |
| 131 | static inline unsigned int get_child(unsigned int n, unsigned int k) |
| 132 | { |
| 133 | return (n * CHILDREN_PER_NODE) + k; |
| 134 | } |
| 135 | |
| 136 | /* |
| 137 | * Return the n'th node of level l from table t. |
| 138 | */ |
| 139 | static inline sector_t *get_node(struct dm_table *t, |
| 140 | unsigned int l, unsigned int n) |
| 141 | { |
| 142 | return t->index[l] + (n * KEYS_PER_NODE); |
| 143 | } |
| 144 | |
| 145 | /* |
| 146 | * Return the highest key that you could lookup from the n'th |
| 147 | * node on level l of the btree. |
| 148 | */ |
| 149 | static sector_t high(struct dm_table *t, unsigned int l, unsigned int n) |
| 150 | { |
| 151 | for (; l < t->depth - 1; l++) |
| 152 | n = get_child(n, CHILDREN_PER_NODE - 1); |
| 153 | |
| 154 | if (n >= t->counts[l]) |
| 155 | return (sector_t) - 1; |
| 156 | |
| 157 | return get_node(t, l, n)[KEYS_PER_NODE - 1]; |
| 158 | } |
| 159 | |
| 160 | /* |
| 161 | * Fills in a level of the btree based on the highs of the level |
| 162 | * below it. |
| 163 | */ |
| 164 | static int setup_btree_index(unsigned int l, struct dm_table *t) |
| 165 | { |
| 166 | unsigned int n, k; |
| 167 | sector_t *node; |
| 168 | |
| 169 | for (n = 0U; n < t->counts[l]; n++) { |
| 170 | node = get_node(t, l, n); |
| 171 | |
| 172 | for (k = 0U; k < KEYS_PER_NODE; k++) |
| 173 | node[k] = high(t, l + 1, get_child(n, k)); |
| 174 | } |
| 175 | |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size) |
| 180 | { |
| 181 | unsigned long size; |
| 182 | void *addr; |
| 183 | |
| 184 | /* |
| 185 | * Check that we're not going to overflow. |
| 186 | */ |
| 187 | if (nmemb > (ULONG_MAX / elem_size)) |
| 188 | return NULL; |
| 189 | |
| 190 | size = nmemb * elem_size; |
| 191 | addr = vmalloc(size); |
| 192 | if (addr) |
| 193 | memset(addr, 0, size); |
| 194 | |
| 195 | return addr; |
| 196 | } |
| 197 | |
| 198 | /* |
| 199 | * highs, and targets are managed as dynamic arrays during a |
| 200 | * table load. |
| 201 | */ |
| 202 | static int alloc_targets(struct dm_table *t, unsigned int num) |
| 203 | { |
| 204 | sector_t *n_highs; |
| 205 | struct dm_target *n_targets; |
| 206 | int n = t->num_targets; |
| 207 | |
| 208 | /* |
| 209 | * Allocate both the target array and offset array at once. |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 210 | * Append an empty entry to catch sectors beyond the end of |
| 211 | * the device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | */ |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 213 | n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) + |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | sizeof(sector_t)); |
| 215 | if (!n_highs) |
| 216 | return -ENOMEM; |
| 217 | |
| 218 | n_targets = (struct dm_target *) (n_highs + num); |
| 219 | |
| 220 | if (n) { |
| 221 | memcpy(n_highs, t->highs, sizeof(*n_highs) * n); |
| 222 | memcpy(n_targets, t->targets, sizeof(*n_targets) * n); |
| 223 | } |
| 224 | |
| 225 | memset(n_highs + n, -1, sizeof(*n_highs) * (num - n)); |
| 226 | vfree(t->highs); |
| 227 | |
| 228 | t->num_allocated = num; |
| 229 | t->highs = n_highs; |
| 230 | t->targets = n_targets; |
| 231 | |
| 232 | return 0; |
| 233 | } |
| 234 | |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 235 | int dm_table_create(struct dm_table **result, fmode_t mode, |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 236 | unsigned num_targets, struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | { |
Dmitry Monakhov | 094262d | 2007-10-19 22:38:51 +0100 | [diff] [blame] | 238 | struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
| 240 | if (!t) |
| 241 | return -ENOMEM; |
| 242 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | INIT_LIST_HEAD(&t->devices); |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 244 | atomic_set(&t->holders, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | |
| 246 | if (!num_targets) |
| 247 | num_targets = KEYS_PER_NODE; |
| 248 | |
| 249 | num_targets = dm_round_up(num_targets, KEYS_PER_NODE); |
| 250 | |
| 251 | if (alloc_targets(t, num_targets)) { |
| 252 | kfree(t); |
| 253 | t = NULL; |
| 254 | return -ENOMEM; |
| 255 | } |
| 256 | |
| 257 | t->mode = mode; |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 258 | t->md = md; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | *result = t; |
| 260 | return 0; |
| 261 | } |
| 262 | |
| 263 | static void free_devices(struct list_head *devices) |
| 264 | { |
| 265 | struct list_head *tmp, *next; |
| 266 | |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 267 | list_for_each_safe(tmp, next, devices) { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 268 | struct dm_dev_internal *dd = |
| 269 | list_entry(tmp, struct dm_dev_internal, list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | kfree(dd); |
| 271 | } |
| 272 | } |
| 273 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 274 | void dm_table_destroy(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | { |
| 276 | unsigned int i; |
| 277 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 278 | while (atomic_read(&t->holders)) |
| 279 | msleep(1); |
| 280 | smp_mb(); |
| 281 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | /* free the indexes (see dm_table_complete) */ |
| 283 | if (t->depth >= 2) |
| 284 | vfree(t->index[t->depth - 2]); |
| 285 | |
| 286 | /* free the targets */ |
| 287 | for (i = 0; i < t->num_targets; i++) { |
| 288 | struct dm_target *tgt = t->targets + i; |
| 289 | |
| 290 | if (tgt->type->dtr) |
| 291 | tgt->type->dtr(tgt); |
| 292 | |
| 293 | dm_put_target_type(tgt->type); |
| 294 | } |
| 295 | |
| 296 | vfree(t->highs); |
| 297 | |
| 298 | /* free the device list */ |
| 299 | if (t->devices.next != &t->devices) { |
| 300 | DMWARN("devices still present during destroy: " |
| 301 | "dm_table_remove_device calls missing"); |
| 302 | |
| 303 | free_devices(&t->devices); |
| 304 | } |
| 305 | |
| 306 | kfree(t); |
| 307 | } |
| 308 | |
| 309 | void dm_table_get(struct dm_table *t) |
| 310 | { |
| 311 | atomic_inc(&t->holders); |
| 312 | } |
| 313 | |
| 314 | void dm_table_put(struct dm_table *t) |
| 315 | { |
| 316 | if (!t) |
| 317 | return; |
| 318 | |
Mikulas Patocka | d581687 | 2009-01-06 03:05:10 +0000 | [diff] [blame] | 319 | smp_mb__before_atomic_dec(); |
| 320 | atomic_dec(&t->holders); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | } |
| 322 | |
| 323 | /* |
| 324 | * Checks to see if we need to extend highs or targets. |
| 325 | */ |
| 326 | static inline int check_space(struct dm_table *t) |
| 327 | { |
| 328 | if (t->num_targets >= t->num_allocated) |
| 329 | return alloc_targets(t, t->num_allocated * 2); |
| 330 | |
| 331 | return 0; |
| 332 | } |
| 333 | |
| 334 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 335 | * See if we've already got a device in the list. |
| 336 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 337 | 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] | 338 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 339 | struct dm_dev_internal *dd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | |
| 341 | list_for_each_entry (dd, l, list) |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 342 | if (dd->dm_dev.bdev->bd_dev == dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 343 | return dd; |
| 344 | |
| 345 | return NULL; |
| 346 | } |
| 347 | |
| 348 | /* |
| 349 | * Open a device so we can use it as a map destination. |
| 350 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 351 | static int open_dev(struct dm_dev_internal *d, dev_t dev, |
| 352 | struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | { |
| 354 | static char *_claim_ptr = "I belong to device-mapper"; |
| 355 | struct block_device *bdev; |
| 356 | |
| 357 | int r; |
| 358 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 359 | BUG_ON(d->dm_dev.bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 361 | bdev = open_by_devnum(dev, d->dm_dev.mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 362 | if (IS_ERR(bdev)) |
| 363 | return PTR_ERR(bdev); |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 364 | r = bd_claim_by_disk(bdev, _claim_ptr, dm_disk(md)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | if (r) |
Al Viro | 9a1c354 | 2008-02-22 20:40:24 -0500 | [diff] [blame] | 366 | blkdev_put(bdev, d->dm_dev.mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 367 | else |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 368 | d->dm_dev.bdev = bdev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | return r; |
| 370 | } |
| 371 | |
| 372 | /* |
| 373 | * Close a device that we've been using. |
| 374 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 375 | 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] | 376 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 377 | if (!d->dm_dev.bdev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | return; |
| 379 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 380 | bd_release_from_disk(d->dm_dev.bdev, dm_disk(md)); |
Al Viro | 9a1c354 | 2008-02-22 20:40:24 -0500 | [diff] [blame] | 381 | blkdev_put(d->dm_dev.bdev, d->dm_dev.mode); |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 382 | d->dm_dev.bdev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 383 | } |
| 384 | |
| 385 | /* |
Mike Anderson | 2cd54d9 | 2007-05-09 02:32:57 -0700 | [diff] [blame] | 386 | * If possible, this checks an area of a destination device is valid. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 388 | static int check_device_area(struct dm_dev_internal *dd, sector_t start, |
| 389 | sector_t len) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 391 | sector_t dev_size = dd->dm_dev.bdev->bd_inode->i_size >> SECTOR_SHIFT; |
Mike Anderson | 2cd54d9 | 2007-05-09 02:32:57 -0700 | [diff] [blame] | 392 | |
| 393 | if (!dev_size) |
| 394 | return 1; |
| 395 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | return ((start < dev_size) && (len <= (dev_size - start))); |
| 397 | } |
| 398 | |
| 399 | /* |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 400 | * This upgrades the mode on an already open dm_dev, being |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 401 | * 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] | 402 | * device and not to touch the existing bdev field in case |
| 403 | * it is accessed concurrently inside dm_table_any_congested(). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | */ |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 405 | 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] | 406 | struct mapped_device *md) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | { |
| 408 | int r; |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 409 | struct dm_dev_internal dd_new, dd_old; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 411 | dd_new = dd_old = *dd; |
| 412 | |
| 413 | dd_new.dm_dev.mode |= new_mode; |
| 414 | dd_new.dm_dev.bdev = NULL; |
| 415 | |
| 416 | r = open_dev(&dd_new, dd->dm_dev.bdev->bd_dev, md); |
| 417 | if (r) |
| 418 | return r; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 420 | dd->dm_dev.mode |= new_mode; |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 421 | close_dev(&dd_old, md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 422 | |
Alasdair G Kergon | 570b9d9 | 2009-04-02 19:55:28 +0100 | [diff] [blame] | 423 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | } |
| 425 | |
| 426 | /* |
| 427 | * Add a device to the list, or just increment the usage count if |
| 428 | * it's already present. |
| 429 | */ |
| 430 | static int __table_get_device(struct dm_table *t, struct dm_target *ti, |
| 431 | const char *path, sector_t start, sector_t len, |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 432 | fmode_t mode, struct dm_dev **result) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | { |
| 434 | int r; |
Andrew Morton | 69a2ce7 | 2008-02-08 02:10:14 +0000 | [diff] [blame] | 435 | dev_t uninitialized_var(dev); |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 436 | struct dm_dev_internal *dd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | unsigned int major, minor; |
| 438 | |
Eric Sesterhenn | 547bc92 | 2006-03-26 18:22:50 +0200 | [diff] [blame] | 439 | BUG_ON(!t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | |
| 441 | if (sscanf(path, "%u:%u", &major, &minor) == 2) { |
| 442 | /* Extract the major/minor numbers */ |
| 443 | dev = MKDEV(major, minor); |
| 444 | if (MAJOR(dev) != major || MINOR(dev) != minor) |
| 445 | return -EOVERFLOW; |
| 446 | } else { |
| 447 | /* convert the path to a device */ |
Christoph Hellwig | 72e8264 | 2008-08-11 00:24:08 +0200 | [diff] [blame] | 448 | struct block_device *bdev = lookup_bdev(path); |
| 449 | |
| 450 | if (IS_ERR(bdev)) |
| 451 | return PTR_ERR(bdev); |
| 452 | dev = bdev->bd_dev; |
| 453 | bdput(bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | } |
| 455 | |
| 456 | dd = find_device(&t->devices, dev); |
| 457 | if (!dd) { |
| 458 | dd = kmalloc(sizeof(*dd), GFP_KERNEL); |
| 459 | if (!dd) |
| 460 | return -ENOMEM; |
| 461 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 462 | dd->dm_dev.mode = mode; |
| 463 | dd->dm_dev.bdev = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 464 | |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 465 | if ((r = open_dev(dd, dev, t->md))) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | kfree(dd); |
| 467 | return r; |
| 468 | } |
| 469 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 470 | format_dev_t(dd->dm_dev.name, dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | |
| 472 | atomic_set(&dd->count, 0); |
| 473 | list_add(&dd->list, &t->devices); |
| 474 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 475 | } else if (dd->dm_dev.mode != (mode | dd->dm_dev.mode)) { |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 476 | r = upgrade_mode(dd, mode, t->md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | if (r) |
| 478 | return r; |
| 479 | } |
| 480 | atomic_inc(&dd->count); |
| 481 | |
| 482 | if (!check_device_area(dd, start, len)) { |
| 483 | DMWARN("device %s too small for target", path); |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 484 | dm_put_device(ti, &dd->dm_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | return -EINVAL; |
| 486 | } |
| 487 | |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 488 | *result = &dd->dm_dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | |
| 490 | return 0; |
| 491 | } |
| 492 | |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 493 | void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev) |
| 494 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 495 | struct request_queue *q = bdev_get_queue(bdev); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 496 | struct io_restrictions *rs = &ti->limits; |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 497 | char b[BDEVNAME_SIZE]; |
| 498 | |
| 499 | if (unlikely(!q)) { |
| 500 | DMWARN("%s: Cannot set limits for nonexistent device %s", |
| 501 | dm_device_name(ti->table->md), bdevname(bdev, b)); |
| 502 | return; |
| 503 | } |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 504 | |
| 505 | /* |
| 506 | * Combine the device limits low. |
| 507 | * |
| 508 | * FIXME: if we move an io_restriction struct |
| 509 | * into q this would just be a call to |
| 510 | * combine_restrictions_low() |
| 511 | */ |
| 512 | rs->max_sectors = |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 513 | min_not_zero(rs->max_sectors, queue_max_sectors(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 514 | |
Milan Broz | 9980c63 | 2008-07-21 12:00:39 +0100 | [diff] [blame] | 515 | /* |
| 516 | * Check if merge fn is supported. |
| 517 | * If not we'll force DM to use PAGE_SIZE or |
| 518 | * smaller I/O, just to be safe. |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 519 | */ |
Milan Broz | 9980c63 | 2008-07-21 12:00:39 +0100 | [diff] [blame] | 520 | |
| 521 | if (q->merge_bvec_fn && !ti->type->merge) |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 522 | rs->max_sectors = |
| 523 | min_not_zero(rs->max_sectors, |
| 524 | (unsigned int) (PAGE_SIZE >> 9)); |
| 525 | |
| 526 | rs->max_phys_segments = |
| 527 | min_not_zero(rs->max_phys_segments, |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 528 | queue_max_phys_segments(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 529 | |
| 530 | rs->max_hw_segments = |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 531 | min_not_zero(rs->max_hw_segments, queue_max_hw_segments(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 532 | |
Martin K. Petersen | e1defc4 | 2009-05-22 17:17:49 -0400 | [diff] [blame] | 533 | rs->logical_block_size = max(rs->logical_block_size, |
| 534 | queue_logical_block_size(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 535 | |
| 536 | rs->max_segment_size = |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 537 | min_not_zero(rs->max_segment_size, queue_max_segment_size(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 538 | |
Neil Brown | 9121250 | 2007-12-13 14:16:04 +0000 | [diff] [blame] | 539 | rs->max_hw_sectors = |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 540 | min_not_zero(rs->max_hw_sectors, queue_max_hw_sectors(q)); |
Neil Brown | 9121250 | 2007-12-13 14:16:04 +0000 | [diff] [blame] | 541 | |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 542 | rs->seg_boundary_mask = |
| 543 | min_not_zero(rs->seg_boundary_mask, |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 544 | queue_segment_boundary(q)); |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 545 | |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 546 | rs->bounce_pfn = min_not_zero(rs->bounce_pfn, queue_bounce_pfn(q)); |
Vasily Averin | 5ec140e | 2007-10-31 08:33:24 +0100 | [diff] [blame] | 547 | |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 548 | rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags); |
| 549 | } |
| 550 | EXPORT_SYMBOL_GPL(dm_set_device_limits); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | |
| 552 | int dm_get_device(struct dm_target *ti, const char *path, sector_t start, |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 553 | sector_t len, fmode_t mode, struct dm_dev **result) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 554 | { |
| 555 | int r = __table_get_device(ti->table, ti, path, |
| 556 | start, len, mode, result); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 557 | |
Bryn Reeves | 3cb4021 | 2006-10-03 01:15:42 -0700 | [diff] [blame] | 558 | if (!r) |
| 559 | dm_set_device_limits(ti, (*result)->bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | |
| 561 | return r; |
| 562 | } |
| 563 | |
| 564 | /* |
| 565 | * Decrement a devices use count and remove it if necessary. |
| 566 | */ |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 567 | void dm_put_device(struct dm_target *ti, struct dm_dev *d) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 568 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 569 | struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal, |
| 570 | dm_dev); |
| 571 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | if (atomic_dec_and_test(&dd->count)) { |
Jun'ichi Nomura | f165921 | 2006-03-27 01:17:59 -0800 | [diff] [blame] | 573 | close_dev(dd, ti->table->md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | list_del(&dd->list); |
| 575 | kfree(dd); |
| 576 | } |
| 577 | } |
| 578 | |
| 579 | /* |
| 580 | * Checks to see if the target joins onto the end of the table. |
| 581 | */ |
| 582 | static int adjoin(struct dm_table *table, struct dm_target *ti) |
| 583 | { |
| 584 | struct dm_target *prev; |
| 585 | |
| 586 | if (!table->num_targets) |
| 587 | return !ti->begin; |
| 588 | |
| 589 | prev = &table->targets[table->num_targets - 1]; |
| 590 | return (ti->begin == (prev->begin + prev->len)); |
| 591 | } |
| 592 | |
| 593 | /* |
| 594 | * Used to dynamically allocate the arg array. |
| 595 | */ |
| 596 | static char **realloc_argv(unsigned *array_size, char **old_argv) |
| 597 | { |
| 598 | char **argv; |
| 599 | unsigned new_size; |
| 600 | |
| 601 | new_size = *array_size ? *array_size * 2 : 64; |
| 602 | argv = kmalloc(new_size * sizeof(*argv), GFP_KERNEL); |
| 603 | if (argv) { |
| 604 | memcpy(argv, old_argv, *array_size * sizeof(*argv)); |
| 605 | *array_size = new_size; |
| 606 | } |
| 607 | |
| 608 | kfree(old_argv); |
| 609 | return argv; |
| 610 | } |
| 611 | |
| 612 | /* |
| 613 | * Destructively splits up the argument list to pass to ctr. |
| 614 | */ |
| 615 | int dm_split_args(int *argc, char ***argvp, char *input) |
| 616 | { |
| 617 | char *start, *end = input, *out, **argv = NULL; |
| 618 | unsigned array_size = 0; |
| 619 | |
| 620 | *argc = 0; |
David Teigland | 814d686 | 2006-06-26 00:27:31 -0700 | [diff] [blame] | 621 | |
| 622 | if (!input) { |
| 623 | *argvp = NULL; |
| 624 | return 0; |
| 625 | } |
| 626 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | argv = realloc_argv(&array_size, argv); |
| 628 | if (!argv) |
| 629 | return -ENOMEM; |
| 630 | |
| 631 | while (1) { |
| 632 | start = end; |
| 633 | |
| 634 | /* Skip whitespace */ |
| 635 | while (*start && isspace(*start)) |
| 636 | start++; |
| 637 | |
| 638 | if (!*start) |
| 639 | break; /* success, we hit the end */ |
| 640 | |
| 641 | /* 'out' is used to remove any back-quotes */ |
| 642 | end = out = start; |
| 643 | while (*end) { |
| 644 | /* Everything apart from '\0' can be quoted */ |
| 645 | if (*end == '\\' && *(end + 1)) { |
| 646 | *out++ = *(end + 1); |
| 647 | end += 2; |
| 648 | continue; |
| 649 | } |
| 650 | |
| 651 | if (isspace(*end)) |
| 652 | break; /* end of token */ |
| 653 | |
| 654 | *out++ = *end++; |
| 655 | } |
| 656 | |
| 657 | /* have we already filled the array ? */ |
| 658 | if ((*argc + 1) > array_size) { |
| 659 | argv = realloc_argv(&array_size, argv); |
| 660 | if (!argv) |
| 661 | return -ENOMEM; |
| 662 | } |
| 663 | |
| 664 | /* we know this is whitespace */ |
| 665 | if (*end) |
| 666 | end++; |
| 667 | |
| 668 | /* terminate the string and put it in the array */ |
| 669 | *out = '\0'; |
| 670 | argv[*argc] = start; |
| 671 | (*argc)++; |
| 672 | } |
| 673 | |
| 674 | *argvp = argv; |
| 675 | return 0; |
| 676 | } |
| 677 | |
| 678 | static void check_for_valid_limits(struct io_restrictions *rs) |
| 679 | { |
| 680 | if (!rs->max_sectors) |
Mike Christie | defd94b | 2005-12-05 02:37:06 -0600 | [diff] [blame] | 681 | rs->max_sectors = SAFE_MAX_SECTORS; |
Neil Brown | 9121250 | 2007-12-13 14:16:04 +0000 | [diff] [blame] | 682 | if (!rs->max_hw_sectors) |
| 683 | rs->max_hw_sectors = SAFE_MAX_SECTORS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 684 | if (!rs->max_phys_segments) |
| 685 | rs->max_phys_segments = MAX_PHYS_SEGMENTS; |
| 686 | if (!rs->max_hw_segments) |
| 687 | rs->max_hw_segments = MAX_HW_SEGMENTS; |
Martin K. Petersen | e1defc4 | 2009-05-22 17:17:49 -0400 | [diff] [blame] | 688 | if (!rs->logical_block_size) |
| 689 | rs->logical_block_size = 1 << SECTOR_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 690 | if (!rs->max_segment_size) |
| 691 | rs->max_segment_size = MAX_SEGMENT_SIZE; |
| 692 | if (!rs->seg_boundary_mask) |
Milan Broz | 0e435ac | 2008-12-03 12:55:08 +0100 | [diff] [blame] | 693 | rs->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK; |
Vasily Averin | 5ec140e | 2007-10-31 08:33:24 +0100 | [diff] [blame] | 694 | if (!rs->bounce_pfn) |
| 695 | rs->bounce_pfn = -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | } |
| 697 | |
| 698 | int dm_table_add_target(struct dm_table *t, const char *type, |
| 699 | sector_t start, sector_t len, char *params) |
| 700 | { |
| 701 | int r = -EINVAL, argc; |
| 702 | char **argv; |
| 703 | struct dm_target *tgt; |
| 704 | |
| 705 | if ((r = check_space(t))) |
| 706 | return r; |
| 707 | |
| 708 | tgt = t->targets + t->num_targets; |
| 709 | memset(tgt, 0, sizeof(*tgt)); |
| 710 | |
| 711 | if (!len) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 712 | DMERR("%s: zero-length target", dm_device_name(t->md)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | return -EINVAL; |
| 714 | } |
| 715 | |
| 716 | tgt->type = dm_get_target_type(type); |
| 717 | if (!tgt->type) { |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 718 | DMERR("%s: %s: unknown target type", dm_device_name(t->md), |
| 719 | type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | return -EINVAL; |
| 721 | } |
| 722 | |
| 723 | tgt->table = t; |
| 724 | tgt->begin = start; |
| 725 | tgt->len = len; |
| 726 | tgt->error = "Unknown error"; |
| 727 | |
| 728 | /* |
| 729 | * Does this target adjoin the previous one ? |
| 730 | */ |
| 731 | if (!adjoin(t, tgt)) { |
| 732 | tgt->error = "Gap in table"; |
| 733 | r = -EINVAL; |
| 734 | goto bad; |
| 735 | } |
| 736 | |
| 737 | r = dm_split_args(&argc, &argv, params); |
| 738 | if (r) { |
| 739 | tgt->error = "couldn't split parameters (insufficient memory)"; |
| 740 | goto bad; |
| 741 | } |
| 742 | |
| 743 | r = tgt->type->ctr(tgt, argc, argv); |
| 744 | kfree(argv); |
| 745 | if (r) |
| 746 | goto bad; |
| 747 | |
| 748 | t->highs[t->num_targets++] = tgt->begin + tgt->len - 1; |
| 749 | |
| 750 | /* FIXME: the plan is to combine high here and then have |
| 751 | * the merge fn apply the target level restrictions. */ |
| 752 | combine_restrictions_low(&t->limits, &tgt->limits); |
| 753 | return 0; |
| 754 | |
| 755 | bad: |
Alasdair G Kergon | 72d9486 | 2006-06-26 00:27:35 -0700 | [diff] [blame] | 756 | DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 757 | dm_put_target_type(tgt->type); |
| 758 | return r; |
| 759 | } |
| 760 | |
| 761 | static int setup_indexes(struct dm_table *t) |
| 762 | { |
| 763 | int i; |
| 764 | unsigned int total = 0; |
| 765 | sector_t *indexes; |
| 766 | |
| 767 | /* allocate the space for *all* the indexes */ |
| 768 | for (i = t->depth - 2; i >= 0; i--) { |
| 769 | t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE); |
| 770 | total += t->counts[i]; |
| 771 | } |
| 772 | |
| 773 | indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE); |
| 774 | if (!indexes) |
| 775 | return -ENOMEM; |
| 776 | |
| 777 | /* set up internal nodes, bottom-up */ |
Jun'ichi Nomura | 82d601d | 2008-02-08 02:10:04 +0000 | [diff] [blame] | 778 | for (i = t->depth - 2; i >= 0; i--) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 779 | t->index[i] = indexes; |
| 780 | indexes += (KEYS_PER_NODE * t->counts[i]); |
| 781 | setup_btree_index(i, t); |
| 782 | } |
| 783 | |
| 784 | return 0; |
| 785 | } |
| 786 | |
| 787 | /* |
| 788 | * Builds the btree to index the map. |
| 789 | */ |
| 790 | int dm_table_complete(struct dm_table *t) |
| 791 | { |
| 792 | int r = 0; |
| 793 | unsigned int leaf_nodes; |
| 794 | |
| 795 | check_for_valid_limits(&t->limits); |
| 796 | |
| 797 | /* how many indexes will the btree have ? */ |
| 798 | leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE); |
| 799 | t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE); |
| 800 | |
| 801 | /* leaf layer has already been set up */ |
| 802 | t->counts[t->depth - 1] = leaf_nodes; |
| 803 | t->index[t->depth - 1] = t->highs; |
| 804 | |
| 805 | if (t->depth >= 2) |
| 806 | r = setup_indexes(t); |
| 807 | |
| 808 | return r; |
| 809 | } |
| 810 | |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 811 | static DEFINE_MUTEX(_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | void dm_table_event_callback(struct dm_table *t, |
| 813 | void (*fn)(void *), void *context) |
| 814 | { |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 815 | mutex_lock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | t->event_fn = fn; |
| 817 | t->event_context = context; |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 818 | mutex_unlock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | } |
| 820 | |
| 821 | void dm_table_event(struct dm_table *t) |
| 822 | { |
| 823 | /* |
| 824 | * You can no longer call dm_table_event() from interrupt |
| 825 | * context, use a bottom half instead. |
| 826 | */ |
| 827 | BUG_ON(in_interrupt()); |
| 828 | |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 829 | mutex_lock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 830 | if (t->event_fn) |
| 831 | t->event_fn(t->event_context); |
Arjan van de Ven | 48c9c27 | 2006-03-27 01:18:20 -0800 | [diff] [blame] | 832 | mutex_unlock(&_event_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | } |
| 834 | |
| 835 | sector_t dm_table_get_size(struct dm_table *t) |
| 836 | { |
| 837 | return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0; |
| 838 | } |
| 839 | |
| 840 | struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index) |
| 841 | { |
Milan Broz | 1435353 | 2006-06-26 00:27:27 -0700 | [diff] [blame] | 842 | if (index >= t->num_targets) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | return NULL; |
| 844 | |
| 845 | return t->targets + index; |
| 846 | } |
| 847 | |
| 848 | /* |
| 849 | * Search the btree for the correct target. |
Jun'ichi Nomura | 512875b | 2007-12-13 14:15:25 +0000 | [diff] [blame] | 850 | * |
| 851 | * Caller should check returned pointer with dm_target_is_valid() |
| 852 | * to trap I/O beyond end of device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | */ |
| 854 | struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) |
| 855 | { |
| 856 | unsigned int l, n = 0, k = 0; |
| 857 | sector_t *node; |
| 858 | |
| 859 | for (l = 0; l < t->depth; l++) { |
| 860 | n = get_child(n, k); |
| 861 | node = get_node(t, l, n); |
| 862 | |
| 863 | for (k = 0; k < KEYS_PER_NODE; k++) |
| 864 | if (node[k] >= sector) |
| 865 | break; |
| 866 | } |
| 867 | |
| 868 | return &t->targets[(KEYS_PER_NODE * n) + k]; |
| 869 | } |
| 870 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 871 | /* |
| 872 | * Set the integrity profile for this device if all devices used have |
| 873 | * matching profiles. |
| 874 | */ |
| 875 | static void dm_table_set_integrity(struct dm_table *t) |
| 876 | { |
| 877 | struct list_head *devices = dm_table_get_devices(t); |
| 878 | struct dm_dev_internal *prev = NULL, *dd = NULL; |
| 879 | |
| 880 | if (!blk_get_integrity(dm_disk(t->md))) |
| 881 | return; |
| 882 | |
| 883 | list_for_each_entry(dd, devices, list) { |
| 884 | if (prev && |
| 885 | blk_integrity_compare(prev->dm_dev.bdev->bd_disk, |
| 886 | dd->dm_dev.bdev->bd_disk) < 0) { |
| 887 | DMWARN("%s: integrity not set: %s and %s mismatch", |
| 888 | dm_device_name(t->md), |
| 889 | prev->dm_dev.bdev->bd_disk->disk_name, |
| 890 | dd->dm_dev.bdev->bd_disk->disk_name); |
| 891 | goto no_integrity; |
| 892 | } |
| 893 | prev = dd; |
| 894 | } |
| 895 | |
| 896 | if (!prev || !bdev_get_integrity(prev->dm_dev.bdev)) |
| 897 | goto no_integrity; |
| 898 | |
| 899 | blk_integrity_register(dm_disk(t->md), |
| 900 | bdev_get_integrity(prev->dm_dev.bdev)); |
| 901 | |
| 902 | return; |
| 903 | |
| 904 | no_integrity: |
| 905 | blk_integrity_register(dm_disk(t->md), NULL); |
| 906 | |
| 907 | return; |
| 908 | } |
| 909 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 910 | void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q) |
| 911 | { |
| 912 | /* |
| 913 | * Make sure we obey the optimistic sub devices |
| 914 | * restrictions. |
| 915 | */ |
| 916 | blk_queue_max_sectors(q, t->limits.max_sectors); |
Martin K. Petersen | ae03bf6 | 2009-05-22 17:17:50 -0400 | [diff] [blame^] | 917 | blk_queue_max_phys_segments(q, t->limits.max_phys_segments); |
| 918 | blk_queue_max_hw_segments(q, t->limits.max_hw_segments); |
| 919 | blk_queue_logical_block_size(q, t->limits.logical_block_size); |
| 920 | blk_queue_max_segment_size(q, t->limits.max_segment_size); |
| 921 | blk_queue_max_hw_sectors(q, t->limits.max_hw_sectors); |
| 922 | blk_queue_segment_boundary(q, t->limits.seg_boundary_mask); |
| 923 | blk_queue_bounce_limit(q, t->limits.bounce_pfn); |
Jens Axboe | c9a3f6d | 2008-04-29 19:12:35 +0200 | [diff] [blame] | 924 | |
NeilBrown | 969429b | 2006-03-27 01:17:49 -0800 | [diff] [blame] | 925 | if (t->limits.no_cluster) |
Jens Axboe | c9a3f6d | 2008-04-29 19:12:35 +0200 | [diff] [blame] | 926 | queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q); |
NeilBrown | 969429b | 2006-03-27 01:17:49 -0800 | [diff] [blame] | 927 | else |
Jens Axboe | c9a3f6d | 2008-04-29 19:12:35 +0200 | [diff] [blame] | 928 | queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q); |
NeilBrown | 969429b | 2006-03-27 01:17:49 -0800 | [diff] [blame] | 929 | |
Martin K. Petersen | 9c47008 | 2009-04-09 00:27:12 +0100 | [diff] [blame] | 930 | dm_table_set_integrity(t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | } |
| 932 | |
| 933 | unsigned int dm_table_get_num_targets(struct dm_table *t) |
| 934 | { |
| 935 | return t->num_targets; |
| 936 | } |
| 937 | |
| 938 | struct list_head *dm_table_get_devices(struct dm_table *t) |
| 939 | { |
| 940 | return &t->devices; |
| 941 | } |
| 942 | |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 943 | fmode_t dm_table_get_mode(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | { |
| 945 | return t->mode; |
| 946 | } |
| 947 | |
| 948 | static void suspend_targets(struct dm_table *t, unsigned postsuspend) |
| 949 | { |
| 950 | int i = t->num_targets; |
| 951 | struct dm_target *ti = t->targets; |
| 952 | |
| 953 | while (i--) { |
| 954 | if (postsuspend) { |
| 955 | if (ti->type->postsuspend) |
| 956 | ti->type->postsuspend(ti); |
| 957 | } else if (ti->type->presuspend) |
| 958 | ti->type->presuspend(ti); |
| 959 | |
| 960 | ti++; |
| 961 | } |
| 962 | } |
| 963 | |
| 964 | void dm_table_presuspend_targets(struct dm_table *t) |
| 965 | { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 966 | if (!t) |
| 967 | return; |
| 968 | |
Adrian Bunk | e8488d0 | 2008-04-24 22:10:51 +0100 | [diff] [blame] | 969 | suspend_targets(t, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 970 | } |
| 971 | |
| 972 | void dm_table_postsuspend_targets(struct dm_table *t) |
| 973 | { |
Alasdair G Kergon | cf222b3 | 2005-07-28 21:15:57 -0700 | [diff] [blame] | 974 | if (!t) |
| 975 | return; |
| 976 | |
Adrian Bunk | e8488d0 | 2008-04-24 22:10:51 +0100 | [diff] [blame] | 977 | suspend_targets(t, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 978 | } |
| 979 | |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 980 | int dm_table_resume_targets(struct dm_table *t) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 981 | { |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 982 | int i, r = 0; |
| 983 | |
| 984 | for (i = 0; i < t->num_targets; i++) { |
| 985 | struct dm_target *ti = t->targets + i; |
| 986 | |
| 987 | if (!ti->type->preresume) |
| 988 | continue; |
| 989 | |
| 990 | r = ti->type->preresume(ti); |
| 991 | if (r) |
| 992 | return r; |
| 993 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 994 | |
| 995 | for (i = 0; i < t->num_targets; i++) { |
| 996 | struct dm_target *ti = t->targets + i; |
| 997 | |
| 998 | if (ti->type->resume) |
| 999 | ti->type->resume(ti); |
| 1000 | } |
Milan Broz | 8757b77 | 2006-10-03 01:15:36 -0700 | [diff] [blame] | 1001 | |
| 1002 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1003 | } |
| 1004 | |
| 1005 | int dm_table_any_congested(struct dm_table *t, int bdi_bits) |
| 1006 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1007 | struct dm_dev_internal *dd; |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1008 | struct list_head *devices = dm_table_get_devices(t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1009 | int r = 0; |
| 1010 | |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1011 | list_for_each_entry(dd, devices, list) { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1012 | struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev); |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 1013 | char b[BDEVNAME_SIZE]; |
| 1014 | |
| 1015 | if (likely(q)) |
| 1016 | r |= bdi_congested(&q->backing_dev_info, bdi_bits); |
| 1017 | else |
| 1018 | DMWARN_LIMIT("%s: any_congested: nonexistent device %s", |
| 1019 | dm_device_name(t->md), |
| 1020 | bdevname(dd->dm_dev.bdev, b)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1021 | } |
| 1022 | |
| 1023 | return r; |
| 1024 | } |
| 1025 | |
| 1026 | void dm_table_unplug_all(struct dm_table *t) |
| 1027 | { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1028 | struct dm_dev_internal *dd; |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1029 | struct list_head *devices = dm_table_get_devices(t); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1030 | |
Paul Jimenez | afb2452 | 2008-02-08 02:09:59 +0000 | [diff] [blame] | 1031 | list_for_each_entry(dd, devices, list) { |
Mikulas Patocka | 82b1519 | 2008-10-10 13:37:09 +0100 | [diff] [blame] | 1032 | struct request_queue *q = bdev_get_queue(dd->dm_dev.bdev); |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 1033 | char b[BDEVNAME_SIZE]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1034 | |
Alasdair G Kergon | 0c2322e | 2008-10-10 13:37:13 +0100 | [diff] [blame] | 1035 | if (likely(q)) |
| 1036 | blk_unplug(q); |
| 1037 | else |
| 1038 | DMWARN_LIMIT("%s: Cannot unplug nonexistent device %s", |
| 1039 | dm_device_name(t->md), |
| 1040 | bdevname(dd->dm_dev.bdev, b)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1041 | } |
| 1042 | } |
| 1043 | |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1044 | struct mapped_device *dm_table_get_md(struct dm_table *t) |
| 1045 | { |
| 1046 | dm_get(t->md); |
| 1047 | |
| 1048 | return t->md; |
| 1049 | } |
| 1050 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1051 | EXPORT_SYMBOL(dm_vcalloc); |
| 1052 | EXPORT_SYMBOL(dm_get_device); |
| 1053 | EXPORT_SYMBOL(dm_put_device); |
| 1054 | EXPORT_SYMBOL(dm_table_event); |
Alasdair G Kergon | d5e404c | 2005-07-12 15:53:05 -0700 | [diff] [blame] | 1055 | EXPORT_SYMBOL(dm_table_get_size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1056 | EXPORT_SYMBOL(dm_table_get_mode); |
Mike Anderson | 1134e5a | 2006-03-27 01:17:54 -0800 | [diff] [blame] | 1057 | EXPORT_SYMBOL(dm_table_get_md); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | EXPORT_SYMBOL(dm_table_put); |
| 1059 | EXPORT_SYMBOL(dm_table_get); |
| 1060 | EXPORT_SYMBOL(dm_table_unplug_all); |