Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1 | /* |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2 | * Copyright (C) 2011-2012 Red Hat UK. |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 3 | * |
| 4 | * This file is released under the GPL. |
| 5 | */ |
| 6 | |
| 7 | #include "dm-thin-metadata.h" |
Mike Snitzer | 4f81a41 | 2012-10-12 21:02:13 +0100 | [diff] [blame] | 8 | #include "dm-bio-prison.h" |
Alasdair G Kergon | 1f4e0ff | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 9 | #include "dm.h" |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 10 | |
| 11 | #include <linux/device-mapper.h> |
| 12 | #include <linux/dm-io.h> |
| 13 | #include <linux/dm-kcopyd.h> |
| 14 | #include <linux/list.h> |
| 15 | #include <linux/init.h> |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/slab.h> |
| 18 | |
| 19 | #define DM_MSG_PREFIX "thin" |
| 20 | |
| 21 | /* |
| 22 | * Tunable constants |
| 23 | */ |
Alasdair G Kergon | 7768ed3 | 2012-07-27 15:07:57 +0100 | [diff] [blame] | 24 | #define ENDIO_HOOK_POOL_SIZE 1024 |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 25 | #define MAPPING_POOL_SIZE 1024 |
| 26 | #define PRISON_CELLS 1024 |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 27 | #define COMMIT_PERIOD HZ |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 28 | |
| 29 | /* |
| 30 | * The block size of the device holding pool data must be |
| 31 | * between 64KB and 1GB. |
| 32 | */ |
| 33 | #define DATA_DEV_BLOCK_SIZE_MIN_SECTORS (64 * 1024 >> SECTOR_SHIFT) |
| 34 | #define DATA_DEV_BLOCK_SIZE_MAX_SECTORS (1024 * 1024 * 1024 >> SECTOR_SHIFT) |
| 35 | |
| 36 | /* |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 37 | * Device id is restricted to 24 bits. |
| 38 | */ |
| 39 | #define MAX_DEV_ID ((1 << 24) - 1) |
| 40 | |
| 41 | /* |
| 42 | * How do we handle breaking sharing of data blocks? |
| 43 | * ================================================= |
| 44 | * |
| 45 | * We use a standard copy-on-write btree to store the mappings for the |
| 46 | * devices (note I'm talking about copy-on-write of the metadata here, not |
| 47 | * the data). When you take an internal snapshot you clone the root node |
| 48 | * of the origin btree. After this there is no concept of an origin or a |
| 49 | * snapshot. They are just two device trees that happen to point to the |
| 50 | * same data blocks. |
| 51 | * |
| 52 | * When we get a write in we decide if it's to a shared data block using |
| 53 | * some timestamp magic. If it is, we have to break sharing. |
| 54 | * |
| 55 | * Let's say we write to a shared block in what was the origin. The |
| 56 | * steps are: |
| 57 | * |
| 58 | * i) plug io further to this physical block. (see bio_prison code). |
| 59 | * |
| 60 | * ii) quiesce any read io to that shared data block. Obviously |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 61 | * including all devices that share this block. (see dm_deferred_set code) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 62 | * |
| 63 | * iii) copy the data block to a newly allocate block. This step can be |
| 64 | * missed out if the io covers the block. (schedule_copy). |
| 65 | * |
| 66 | * iv) insert the new mapping into the origin's btree |
Joe Thornber | fe878f3 | 2012-03-28 18:41:24 +0100 | [diff] [blame] | 67 | * (process_prepared_mapping). This act of inserting breaks some |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 68 | * sharing of btree nodes between the two devices. Breaking sharing only |
| 69 | * effects the btree of that specific device. Btrees for the other |
| 70 | * devices that share the block never change. The btree for the origin |
| 71 | * device as it was after the last commit is untouched, ie. we're using |
| 72 | * persistent data structures in the functional programming sense. |
| 73 | * |
| 74 | * v) unplug io to this physical block, including the io that triggered |
| 75 | * the breaking of sharing. |
| 76 | * |
| 77 | * Steps (ii) and (iii) occur in parallel. |
| 78 | * |
| 79 | * The metadata _doesn't_ need to be committed before the io continues. We |
| 80 | * get away with this because the io is always written to a _new_ block. |
| 81 | * If there's a crash, then: |
| 82 | * |
| 83 | * - The origin mapping will point to the old origin block (the shared |
| 84 | * one). This will contain the data as it was before the io that triggered |
| 85 | * the breaking of sharing came in. |
| 86 | * |
| 87 | * - The snap mapping still points to the old block. As it would after |
| 88 | * the commit. |
| 89 | * |
| 90 | * The downside of this scheme is the timestamp magic isn't perfect, and |
| 91 | * will continue to think that data block in the snapshot device is shared |
| 92 | * even after the write to the origin has broken sharing. I suspect data |
| 93 | * blocks will typically be shared by many different devices, so we're |
| 94 | * breaking sharing n + 1 times, rather than n, where n is the number of |
| 95 | * devices that reference this data block. At the moment I think the |
| 96 | * benefits far, far outweigh the disadvantages. |
| 97 | */ |
| 98 | |
| 99 | /*----------------------------------------------------------------*/ |
| 100 | |
| 101 | /* |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 102 | * Key building. |
| 103 | */ |
| 104 | static void build_data_key(struct dm_thin_device *td, |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 105 | dm_block_t b, struct dm_cell_key *key) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 106 | { |
| 107 | key->virtual = 0; |
| 108 | key->dev = dm_thin_dev_id(td); |
| 109 | key->block = b; |
| 110 | } |
| 111 | |
| 112 | static void build_virtual_key(struct dm_thin_device *td, dm_block_t b, |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 113 | struct dm_cell_key *key) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 114 | { |
| 115 | key->virtual = 1; |
| 116 | key->dev = dm_thin_dev_id(td); |
| 117 | key->block = b; |
| 118 | } |
| 119 | |
| 120 | /*----------------------------------------------------------------*/ |
| 121 | |
| 122 | /* |
| 123 | * A pool device ties together a metadata device and a data device. It |
| 124 | * also provides the interface for creating and destroying internal |
| 125 | * devices. |
| 126 | */ |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 127 | struct dm_thin_new_mapping; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 128 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 129 | /* |
| 130 | * The pool runs in 3 modes. Ordered in degraded order for comparisons. |
| 131 | */ |
| 132 | enum pool_mode { |
| 133 | PM_WRITE, /* metadata may be changed */ |
| 134 | PM_READ_ONLY, /* metadata may not be changed */ |
| 135 | PM_FAIL, /* all I/O fails */ |
| 136 | }; |
| 137 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 138 | struct pool_features { |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 139 | enum pool_mode mode; |
| 140 | |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 141 | bool zero_new_blocks:1; |
| 142 | bool discard_enabled:1; |
| 143 | bool discard_passdown:1; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 144 | }; |
| 145 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 146 | struct thin_c; |
| 147 | typedef void (*process_bio_fn)(struct thin_c *tc, struct bio *bio); |
| 148 | typedef void (*process_mapping_fn)(struct dm_thin_new_mapping *m); |
| 149 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 150 | struct pool { |
| 151 | struct list_head list; |
| 152 | struct dm_target *ti; /* Only set if a pool target is bound */ |
| 153 | |
| 154 | struct mapped_device *pool_md; |
| 155 | struct block_device *md_dev; |
| 156 | struct dm_pool_metadata *pmd; |
| 157 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 158 | dm_block_t low_water_blocks; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 159 | uint32_t sectors_per_block; |
Mikulas Patocka | f9a8e0c | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 160 | int sectors_per_block_shift; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 161 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 162 | struct pool_features pf; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 163 | unsigned low_water_triggered:1; /* A dm event has been sent */ |
| 164 | unsigned no_free_space:1; /* A -ENOSPC warning has been issued */ |
| 165 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 166 | struct dm_bio_prison *prison; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 167 | struct dm_kcopyd_client *copier; |
| 168 | |
| 169 | struct workqueue_struct *wq; |
| 170 | struct work_struct worker; |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 171 | struct delayed_work waker; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 172 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 173 | unsigned long last_commit_jiffies; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 174 | unsigned ref_count; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 175 | |
| 176 | spinlock_t lock; |
| 177 | struct bio_list deferred_bios; |
| 178 | struct bio_list deferred_flush_bios; |
| 179 | struct list_head prepared_mappings; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 180 | struct list_head prepared_discards; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 181 | |
| 182 | struct bio_list retry_on_resume_list; |
| 183 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 184 | struct dm_deferred_set *shared_read_ds; |
| 185 | struct dm_deferred_set *all_io_ds; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 186 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 187 | struct dm_thin_new_mapping *next_mapping; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 188 | mempool_t *mapping_pool; |
| 189 | mempool_t *endio_hook_pool; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 190 | |
| 191 | process_bio_fn process_bio; |
| 192 | process_bio_fn process_discard; |
| 193 | |
| 194 | process_mapping_fn process_prepared_mapping; |
| 195 | process_mapping_fn process_prepared_discard; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 196 | }; |
| 197 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 198 | static enum pool_mode get_pool_mode(struct pool *pool); |
| 199 | static void set_pool_mode(struct pool *pool, enum pool_mode mode); |
| 200 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 201 | /* |
| 202 | * Target context for a pool. |
| 203 | */ |
| 204 | struct pool_c { |
| 205 | struct dm_target *ti; |
| 206 | struct pool *pool; |
| 207 | struct dm_dev *data_dev; |
| 208 | struct dm_dev *metadata_dev; |
| 209 | struct dm_target_callbacks callbacks; |
| 210 | |
| 211 | dm_block_t low_water_blocks; |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 212 | struct pool_features requested_pf; /* Features requested during table load */ |
| 213 | struct pool_features adjusted_pf; /* Features used after adjusting for constituent devices */ |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 214 | }; |
| 215 | |
| 216 | /* |
| 217 | * Target context for a thin. |
| 218 | */ |
| 219 | struct thin_c { |
| 220 | struct dm_dev *pool_dev; |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 221 | struct dm_dev *origin_dev; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 222 | dm_thin_id dev_id; |
| 223 | |
| 224 | struct pool *pool; |
| 225 | struct dm_thin_device *td; |
| 226 | }; |
| 227 | |
| 228 | /*----------------------------------------------------------------*/ |
| 229 | |
| 230 | /* |
| 231 | * A global list of pools that uses a struct mapped_device as a key. |
| 232 | */ |
| 233 | static struct dm_thin_pool_table { |
| 234 | struct mutex mutex; |
| 235 | struct list_head pools; |
| 236 | } dm_thin_pool_table; |
| 237 | |
| 238 | static void pool_table_init(void) |
| 239 | { |
| 240 | mutex_init(&dm_thin_pool_table.mutex); |
| 241 | INIT_LIST_HEAD(&dm_thin_pool_table.pools); |
| 242 | } |
| 243 | |
| 244 | static void __pool_table_insert(struct pool *pool) |
| 245 | { |
| 246 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 247 | list_add(&pool->list, &dm_thin_pool_table.pools); |
| 248 | } |
| 249 | |
| 250 | static void __pool_table_remove(struct pool *pool) |
| 251 | { |
| 252 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 253 | list_del(&pool->list); |
| 254 | } |
| 255 | |
| 256 | static struct pool *__pool_table_lookup(struct mapped_device *md) |
| 257 | { |
| 258 | struct pool *pool = NULL, *tmp; |
| 259 | |
| 260 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 261 | |
| 262 | list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) { |
| 263 | if (tmp->pool_md == md) { |
| 264 | pool = tmp; |
| 265 | break; |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | return pool; |
| 270 | } |
| 271 | |
| 272 | static struct pool *__pool_table_lookup_metadata_dev(struct block_device *md_dev) |
| 273 | { |
| 274 | struct pool *pool = NULL, *tmp; |
| 275 | |
| 276 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 277 | |
| 278 | list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) { |
| 279 | if (tmp->md_dev == md_dev) { |
| 280 | pool = tmp; |
| 281 | break; |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | return pool; |
| 286 | } |
| 287 | |
| 288 | /*----------------------------------------------------------------*/ |
| 289 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 290 | struct dm_thin_endio_hook { |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 291 | struct thin_c *tc; |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 292 | struct dm_deferred_entry *shared_read_entry; |
| 293 | struct dm_deferred_entry *all_io_entry; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 294 | struct dm_thin_new_mapping *overwrite_mapping; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 295 | }; |
| 296 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 297 | static void __requeue_bio_list(struct thin_c *tc, struct bio_list *master) |
| 298 | { |
| 299 | struct bio *bio; |
| 300 | struct bio_list bios; |
| 301 | |
| 302 | bio_list_init(&bios); |
| 303 | bio_list_merge(&bios, master); |
| 304 | bio_list_init(master); |
| 305 | |
| 306 | while ((bio = bio_list_pop(&bios))) { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 307 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
| 308 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 309 | if (h->tc == tc) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 310 | bio_endio(bio, DM_ENDIO_REQUEUE); |
| 311 | else |
| 312 | bio_list_add(master, bio); |
| 313 | } |
| 314 | } |
| 315 | |
| 316 | static void requeue_io(struct thin_c *tc) |
| 317 | { |
| 318 | struct pool *pool = tc->pool; |
| 319 | unsigned long flags; |
| 320 | |
| 321 | spin_lock_irqsave(&pool->lock, flags); |
| 322 | __requeue_bio_list(tc, &pool->deferred_bios); |
| 323 | __requeue_bio_list(tc, &pool->retry_on_resume_list); |
| 324 | spin_unlock_irqrestore(&pool->lock, flags); |
| 325 | } |
| 326 | |
| 327 | /* |
| 328 | * This section of code contains the logic for processing a thin device's IO. |
| 329 | * Much of the code depends on pool object resources (lists, workqueues, etc) |
| 330 | * but most is exclusively called from the thin target rather than the thin-pool |
| 331 | * target. |
| 332 | */ |
| 333 | |
| 334 | static dm_block_t get_bio_block(struct thin_c *tc, struct bio *bio) |
| 335 | { |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 336 | sector_t block_nr = bio->bi_sector; |
| 337 | |
Mikulas Patocka | f9a8e0c | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 338 | if (tc->pool->sectors_per_block_shift < 0) |
| 339 | (void) sector_div(block_nr, tc->pool->sectors_per_block); |
| 340 | else |
| 341 | block_nr >>= tc->pool->sectors_per_block_shift; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 342 | |
| 343 | return block_nr; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 344 | } |
| 345 | |
| 346 | static void remap(struct thin_c *tc, struct bio *bio, dm_block_t block) |
| 347 | { |
| 348 | struct pool *pool = tc->pool; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 349 | sector_t bi_sector = bio->bi_sector; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 350 | |
| 351 | bio->bi_bdev = tc->pool_dev->bdev; |
Mikulas Patocka | f9a8e0c | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 352 | if (tc->pool->sectors_per_block_shift < 0) |
| 353 | bio->bi_sector = (block * pool->sectors_per_block) + |
| 354 | sector_div(bi_sector, pool->sectors_per_block); |
| 355 | else |
| 356 | bio->bi_sector = (block << pool->sectors_per_block_shift) | |
| 357 | (bi_sector & (pool->sectors_per_block - 1)); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 358 | } |
| 359 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 360 | static void remap_to_origin(struct thin_c *tc, struct bio *bio) |
| 361 | { |
| 362 | bio->bi_bdev = tc->origin_dev->bdev; |
| 363 | } |
| 364 | |
Joe Thornber | 4afdd68 | 2012-07-27 15:08:14 +0100 | [diff] [blame] | 365 | static int bio_triggers_commit(struct thin_c *tc, struct bio *bio) |
| 366 | { |
| 367 | return (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && |
| 368 | dm_thin_changed_this_transaction(tc->td); |
| 369 | } |
| 370 | |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 371 | static void inc_all_io_entry(struct pool *pool, struct bio *bio) |
| 372 | { |
| 373 | struct dm_thin_endio_hook *h; |
| 374 | |
| 375 | if (bio->bi_rw & REQ_DISCARD) |
| 376 | return; |
| 377 | |
| 378 | h = dm_get_mapinfo(bio)->ptr; |
| 379 | h->all_io_entry = dm_deferred_entry_inc(pool->all_io_ds); |
| 380 | } |
| 381 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 382 | static void issue(struct thin_c *tc, struct bio *bio) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 383 | { |
| 384 | struct pool *pool = tc->pool; |
| 385 | unsigned long flags; |
| 386 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 387 | if (!bio_triggers_commit(tc, bio)) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 388 | generic_make_request(bio); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 389 | return; |
| 390 | } |
| 391 | |
| 392 | /* |
| 393 | * Complete bio with an error if earlier I/O caused changes to |
| 394 | * the metadata that can't be committed e.g, due to I/O errors |
| 395 | * on the metadata device. |
| 396 | */ |
| 397 | if (dm_thin_aborted_changes(tc->td)) { |
| 398 | bio_io_error(bio); |
| 399 | return; |
| 400 | } |
| 401 | |
| 402 | /* |
| 403 | * Batch together any bios that trigger commits and then issue a |
| 404 | * single commit for them in process_deferred_bios(). |
| 405 | */ |
| 406 | spin_lock_irqsave(&pool->lock, flags); |
| 407 | bio_list_add(&pool->deferred_flush_bios, bio); |
| 408 | spin_unlock_irqrestore(&pool->lock, flags); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 409 | } |
| 410 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 411 | static void remap_to_origin_and_issue(struct thin_c *tc, struct bio *bio) |
| 412 | { |
| 413 | remap_to_origin(tc, bio); |
| 414 | issue(tc, bio); |
| 415 | } |
| 416 | |
| 417 | static void remap_and_issue(struct thin_c *tc, struct bio *bio, |
| 418 | dm_block_t block) |
| 419 | { |
| 420 | remap(tc, bio, block); |
| 421 | issue(tc, bio); |
| 422 | } |
| 423 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 424 | /* |
| 425 | * wake_worker() is used when new work is queued and when pool_resume is |
| 426 | * ready to continue deferred IO processing. |
| 427 | */ |
| 428 | static void wake_worker(struct pool *pool) |
| 429 | { |
| 430 | queue_work(pool->wq, &pool->worker); |
| 431 | } |
| 432 | |
| 433 | /*----------------------------------------------------------------*/ |
| 434 | |
| 435 | /* |
| 436 | * Bio endio functions. |
| 437 | */ |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 438 | struct dm_thin_new_mapping { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 439 | struct list_head list; |
| 440 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 441 | unsigned quiesced:1; |
| 442 | unsigned prepared:1; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 443 | unsigned pass_discard:1; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 444 | |
| 445 | struct thin_c *tc; |
| 446 | dm_block_t virt_block; |
| 447 | dm_block_t data_block; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 448 | struct dm_bio_prison_cell *cell, *cell2; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 449 | int err; |
| 450 | |
| 451 | /* |
| 452 | * If the bio covers the whole area of a block then we can avoid |
| 453 | * zeroing or copying. Instead this bio is hooked. The bio will |
| 454 | * still be in the cell, so care has to be taken to avoid issuing |
| 455 | * the bio twice. |
| 456 | */ |
| 457 | struct bio *bio; |
| 458 | bio_end_io_t *saved_bi_end_io; |
| 459 | }; |
| 460 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 461 | static void __maybe_add_mapping(struct dm_thin_new_mapping *m) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 462 | { |
| 463 | struct pool *pool = m->tc->pool; |
| 464 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 465 | if (m->quiesced && m->prepared) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 466 | list_add(&m->list, &pool->prepared_mappings); |
| 467 | wake_worker(pool); |
| 468 | } |
| 469 | } |
| 470 | |
| 471 | static void copy_complete(int read_err, unsigned long write_err, void *context) |
| 472 | { |
| 473 | unsigned long flags; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 474 | struct dm_thin_new_mapping *m = context; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 475 | struct pool *pool = m->tc->pool; |
| 476 | |
| 477 | m->err = read_err || write_err ? -EIO : 0; |
| 478 | |
| 479 | spin_lock_irqsave(&pool->lock, flags); |
| 480 | m->prepared = 1; |
| 481 | __maybe_add_mapping(m); |
| 482 | spin_unlock_irqrestore(&pool->lock, flags); |
| 483 | } |
| 484 | |
| 485 | static void overwrite_endio(struct bio *bio, int err) |
| 486 | { |
| 487 | unsigned long flags; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 488 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
| 489 | struct dm_thin_new_mapping *m = h->overwrite_mapping; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 490 | struct pool *pool = m->tc->pool; |
| 491 | |
| 492 | m->err = err; |
| 493 | |
| 494 | spin_lock_irqsave(&pool->lock, flags); |
| 495 | m->prepared = 1; |
| 496 | __maybe_add_mapping(m); |
| 497 | spin_unlock_irqrestore(&pool->lock, flags); |
| 498 | } |
| 499 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 500 | /*----------------------------------------------------------------*/ |
| 501 | |
| 502 | /* |
| 503 | * Workqueue. |
| 504 | */ |
| 505 | |
| 506 | /* |
| 507 | * Prepared mapping jobs. |
| 508 | */ |
| 509 | |
| 510 | /* |
| 511 | * This sends the bios in the cell back to the deferred_bios list. |
| 512 | */ |
Joe Thornber | 2aab385 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 513 | static void cell_defer(struct thin_c *tc, struct dm_bio_prison_cell *cell) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 514 | { |
| 515 | struct pool *pool = tc->pool; |
| 516 | unsigned long flags; |
| 517 | |
| 518 | spin_lock_irqsave(&pool->lock, flags); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 519 | dm_cell_release(cell, &pool->deferred_bios); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 520 | spin_unlock_irqrestore(&tc->pool->lock, flags); |
| 521 | |
| 522 | wake_worker(pool); |
| 523 | } |
| 524 | |
| 525 | /* |
Joe Thornber | b7ca9c9 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 526 | * Same as cell_defer except it omits the original holder of the cell. |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 527 | */ |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 528 | static void cell_defer_no_holder(struct thin_c *tc, struct dm_bio_prison_cell *cell) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 529 | { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 530 | struct pool *pool = tc->pool; |
| 531 | unsigned long flags; |
| 532 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 533 | spin_lock_irqsave(&pool->lock, flags); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 534 | dm_cell_release_no_holder(cell, &pool->deferred_bios); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 535 | spin_unlock_irqrestore(&pool->lock, flags); |
| 536 | |
| 537 | wake_worker(pool); |
| 538 | } |
| 539 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 540 | static void process_prepared_mapping_fail(struct dm_thin_new_mapping *m) |
| 541 | { |
| 542 | if (m->bio) |
| 543 | m->bio->bi_end_io = m->saved_bi_end_io; |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 544 | dm_cell_error(m->cell); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 545 | list_del(&m->list); |
| 546 | mempool_free(m, m->tc->pool->mapping_pool); |
| 547 | } |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 548 | static void process_prepared_mapping(struct dm_thin_new_mapping *m) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 549 | { |
| 550 | struct thin_c *tc = m->tc; |
| 551 | struct bio *bio; |
| 552 | int r; |
| 553 | |
| 554 | bio = m->bio; |
| 555 | if (bio) |
| 556 | bio->bi_end_io = m->saved_bi_end_io; |
| 557 | |
| 558 | if (m->err) { |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 559 | dm_cell_error(m->cell); |
Joe Thornber | 905386f | 2012-07-27 15:08:05 +0100 | [diff] [blame] | 560 | goto out; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 561 | } |
| 562 | |
| 563 | /* |
| 564 | * Commit the prepared block into the mapping btree. |
| 565 | * Any I/O for this block arriving after this point will get |
| 566 | * remapped to it directly. |
| 567 | */ |
| 568 | r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block); |
| 569 | if (r) { |
| 570 | DMERR("dm_thin_insert_block() failed"); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 571 | dm_cell_error(m->cell); |
Joe Thornber | 905386f | 2012-07-27 15:08:05 +0100 | [diff] [blame] | 572 | goto out; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 573 | } |
| 574 | |
| 575 | /* |
| 576 | * Release any bios held while the block was being provisioned. |
| 577 | * If we are processing a write bio that completely covers the block, |
| 578 | * we already processed it so can ignore it now when processing |
| 579 | * the bios in the cell. |
| 580 | */ |
| 581 | if (bio) { |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 582 | cell_defer_no_holder(tc, m->cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 583 | bio_endio(bio, 0); |
| 584 | } else |
Joe Thornber | 2aab385 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 585 | cell_defer(tc, m->cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 586 | |
Joe Thornber | 905386f | 2012-07-27 15:08:05 +0100 | [diff] [blame] | 587 | out: |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 588 | list_del(&m->list); |
| 589 | mempool_free(m, tc->pool->mapping_pool); |
| 590 | } |
| 591 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 592 | static void process_prepared_discard_fail(struct dm_thin_new_mapping *m) |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 593 | { |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 594 | struct thin_c *tc = m->tc; |
| 595 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 596 | bio_io_error(m->bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 597 | cell_defer_no_holder(tc, m->cell); |
| 598 | cell_defer_no_holder(tc, m->cell2); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 599 | mempool_free(m, tc->pool->mapping_pool); |
| 600 | } |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 601 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 602 | static void process_prepared_discard_passdown(struct dm_thin_new_mapping *m) |
| 603 | { |
| 604 | struct thin_c *tc = m->tc; |
| 605 | |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 606 | inc_all_io_entry(tc->pool, m->bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 607 | cell_defer_no_holder(tc, m->cell); |
| 608 | cell_defer_no_holder(tc, m->cell2); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 609 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 610 | if (m->pass_discard) |
| 611 | remap_and_issue(tc, m->bio, m->data_block); |
| 612 | else |
| 613 | bio_endio(m->bio, 0); |
| 614 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 615 | mempool_free(m, tc->pool->mapping_pool); |
| 616 | } |
| 617 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 618 | static void process_prepared_discard(struct dm_thin_new_mapping *m) |
| 619 | { |
| 620 | int r; |
| 621 | struct thin_c *tc = m->tc; |
| 622 | |
| 623 | r = dm_thin_remove_block(tc->td, m->virt_block); |
| 624 | if (r) |
| 625 | DMERR("dm_thin_remove_block() failed"); |
| 626 | |
| 627 | process_prepared_discard_passdown(m); |
| 628 | } |
| 629 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 630 | static void process_prepared(struct pool *pool, struct list_head *head, |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 631 | process_mapping_fn *fn) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 632 | { |
| 633 | unsigned long flags; |
| 634 | struct list_head maps; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 635 | struct dm_thin_new_mapping *m, *tmp; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 636 | |
| 637 | INIT_LIST_HEAD(&maps); |
| 638 | spin_lock_irqsave(&pool->lock, flags); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 639 | list_splice_init(head, &maps); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 640 | spin_unlock_irqrestore(&pool->lock, flags); |
| 641 | |
| 642 | list_for_each_entry_safe(m, tmp, &maps, list) |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 643 | (*fn)(m); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 644 | } |
| 645 | |
| 646 | /* |
| 647 | * Deferred bio jobs. |
| 648 | */ |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 649 | static int io_overlaps_block(struct pool *pool, struct bio *bio) |
| 650 | { |
Mikulas Patocka | f9a8e0c | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 651 | return bio->bi_size == (pool->sectors_per_block << SECTOR_SHIFT); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 652 | } |
| 653 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 654 | static int io_overwrites_block(struct pool *pool, struct bio *bio) |
| 655 | { |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 656 | return (bio_data_dir(bio) == WRITE) && |
| 657 | io_overlaps_block(pool, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 658 | } |
| 659 | |
| 660 | static void save_and_set_endio(struct bio *bio, bio_end_io_t **save, |
| 661 | bio_end_io_t *fn) |
| 662 | { |
| 663 | *save = bio->bi_end_io; |
| 664 | bio->bi_end_io = fn; |
| 665 | } |
| 666 | |
| 667 | static int ensure_next_mapping(struct pool *pool) |
| 668 | { |
| 669 | if (pool->next_mapping) |
| 670 | return 0; |
| 671 | |
| 672 | pool->next_mapping = mempool_alloc(pool->mapping_pool, GFP_ATOMIC); |
| 673 | |
| 674 | return pool->next_mapping ? 0 : -ENOMEM; |
| 675 | } |
| 676 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 677 | static struct dm_thin_new_mapping *get_next_mapping(struct pool *pool) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 678 | { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 679 | struct dm_thin_new_mapping *r = pool->next_mapping; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 680 | |
| 681 | BUG_ON(!pool->next_mapping); |
| 682 | |
| 683 | pool->next_mapping = NULL; |
| 684 | |
| 685 | return r; |
| 686 | } |
| 687 | |
| 688 | static void schedule_copy(struct thin_c *tc, dm_block_t virt_block, |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 689 | struct dm_dev *origin, dm_block_t data_origin, |
| 690 | dm_block_t data_dest, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 691 | struct dm_bio_prison_cell *cell, struct bio *bio) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 692 | { |
| 693 | int r; |
| 694 | struct pool *pool = tc->pool; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 695 | struct dm_thin_new_mapping *m = get_next_mapping(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 696 | |
| 697 | INIT_LIST_HEAD(&m->list); |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 698 | m->quiesced = 0; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 699 | m->prepared = 0; |
| 700 | m->tc = tc; |
| 701 | m->virt_block = virt_block; |
| 702 | m->data_block = data_dest; |
| 703 | m->cell = cell; |
| 704 | m->err = 0; |
| 705 | m->bio = NULL; |
| 706 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 707 | if (!dm_deferred_set_add_work(pool->shared_read_ds, &m->list)) |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 708 | m->quiesced = 1; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 709 | |
| 710 | /* |
| 711 | * IO to pool_dev remaps to the pool target's data_dev. |
| 712 | * |
| 713 | * If the whole block of data is being overwritten, we can issue the |
| 714 | * bio immediately. Otherwise we use kcopyd to clone the data first. |
| 715 | */ |
| 716 | if (io_overwrites_block(pool, bio)) { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 717 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
| 718 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 719 | h->overwrite_mapping = m; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 720 | m->bio = bio; |
| 721 | save_and_set_endio(bio, &m->saved_bi_end_io, overwrite_endio); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 722 | inc_all_io_entry(pool, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 723 | remap_and_issue(tc, bio, data_dest); |
| 724 | } else { |
| 725 | struct dm_io_region from, to; |
| 726 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 727 | from.bdev = origin->bdev; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 728 | from.sector = data_origin * pool->sectors_per_block; |
| 729 | from.count = pool->sectors_per_block; |
| 730 | |
| 731 | to.bdev = tc->pool_dev->bdev; |
| 732 | to.sector = data_dest * pool->sectors_per_block; |
| 733 | to.count = pool->sectors_per_block; |
| 734 | |
| 735 | r = dm_kcopyd_copy(pool->copier, &from, 1, &to, |
| 736 | 0, copy_complete, m); |
| 737 | if (r < 0) { |
| 738 | mempool_free(m, pool->mapping_pool); |
| 739 | DMERR("dm_kcopyd_copy() failed"); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 740 | dm_cell_error(cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 741 | } |
| 742 | } |
| 743 | } |
| 744 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 745 | static void schedule_internal_copy(struct thin_c *tc, dm_block_t virt_block, |
| 746 | dm_block_t data_origin, dm_block_t data_dest, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 747 | struct dm_bio_prison_cell *cell, struct bio *bio) |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 748 | { |
| 749 | schedule_copy(tc, virt_block, tc->pool_dev, |
| 750 | data_origin, data_dest, cell, bio); |
| 751 | } |
| 752 | |
| 753 | static void schedule_external_copy(struct thin_c *tc, dm_block_t virt_block, |
| 754 | dm_block_t data_dest, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 755 | struct dm_bio_prison_cell *cell, struct bio *bio) |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 756 | { |
| 757 | schedule_copy(tc, virt_block, tc->origin_dev, |
| 758 | virt_block, data_dest, cell, bio); |
| 759 | } |
| 760 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 761 | static void schedule_zero(struct thin_c *tc, dm_block_t virt_block, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 762 | dm_block_t data_block, struct dm_bio_prison_cell *cell, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 763 | struct bio *bio) |
| 764 | { |
| 765 | struct pool *pool = tc->pool; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 766 | struct dm_thin_new_mapping *m = get_next_mapping(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 767 | |
| 768 | INIT_LIST_HEAD(&m->list); |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 769 | m->quiesced = 1; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 770 | m->prepared = 0; |
| 771 | m->tc = tc; |
| 772 | m->virt_block = virt_block; |
| 773 | m->data_block = data_block; |
| 774 | m->cell = cell; |
| 775 | m->err = 0; |
| 776 | m->bio = NULL; |
| 777 | |
| 778 | /* |
| 779 | * If the whole block of data is being overwritten or we are not |
| 780 | * zeroing pre-existing data, we can issue the bio immediately. |
| 781 | * Otherwise we use kcopyd to zero the data first. |
| 782 | */ |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 783 | if (!pool->pf.zero_new_blocks) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 784 | process_prepared_mapping(m); |
| 785 | |
| 786 | else if (io_overwrites_block(pool, bio)) { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 787 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
| 788 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 789 | h->overwrite_mapping = m; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 790 | m->bio = bio; |
| 791 | save_and_set_endio(bio, &m->saved_bi_end_io, overwrite_endio); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 792 | inc_all_io_entry(pool, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 793 | remap_and_issue(tc, bio, data_block); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 794 | } else { |
| 795 | int r; |
| 796 | struct dm_io_region to; |
| 797 | |
| 798 | to.bdev = tc->pool_dev->bdev; |
| 799 | to.sector = data_block * pool->sectors_per_block; |
| 800 | to.count = pool->sectors_per_block; |
| 801 | |
| 802 | r = dm_kcopyd_zero(pool->copier, 1, &to, 0, copy_complete, m); |
| 803 | if (r < 0) { |
| 804 | mempool_free(m, pool->mapping_pool); |
| 805 | DMERR("dm_kcopyd_zero() failed"); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 806 | dm_cell_error(cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 807 | } |
| 808 | } |
| 809 | } |
| 810 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 811 | static int commit(struct pool *pool) |
| 812 | { |
| 813 | int r; |
| 814 | |
| 815 | r = dm_pool_commit_metadata(pool->pmd); |
| 816 | if (r) |
| 817 | DMERR("commit failed, error = %d", r); |
| 818 | |
| 819 | return r; |
| 820 | } |
| 821 | |
| 822 | /* |
| 823 | * A non-zero return indicates read_only or fail_io mode. |
| 824 | * Many callers don't care about the return value. |
| 825 | */ |
| 826 | static int commit_or_fallback(struct pool *pool) |
| 827 | { |
| 828 | int r; |
| 829 | |
| 830 | if (get_pool_mode(pool) != PM_WRITE) |
| 831 | return -EINVAL; |
| 832 | |
| 833 | r = commit(pool); |
| 834 | if (r) |
| 835 | set_pool_mode(pool, PM_READ_ONLY); |
| 836 | |
| 837 | return r; |
| 838 | } |
| 839 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 840 | static int alloc_data_block(struct thin_c *tc, dm_block_t *result) |
| 841 | { |
| 842 | int r; |
| 843 | dm_block_t free_blocks; |
| 844 | unsigned long flags; |
| 845 | struct pool *pool = tc->pool; |
| 846 | |
| 847 | r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); |
| 848 | if (r) |
| 849 | return r; |
| 850 | |
| 851 | if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) { |
| 852 | DMWARN("%s: reached low water mark, sending event.", |
| 853 | dm_device_name(pool->pool_md)); |
| 854 | spin_lock_irqsave(&pool->lock, flags); |
| 855 | pool->low_water_triggered = 1; |
| 856 | spin_unlock_irqrestore(&pool->lock, flags); |
| 857 | dm_table_event(pool->ti->table); |
| 858 | } |
| 859 | |
| 860 | if (!free_blocks) { |
| 861 | if (pool->no_free_space) |
| 862 | return -ENOSPC; |
| 863 | else { |
| 864 | /* |
| 865 | * Try to commit to see if that will free up some |
| 866 | * more space. |
| 867 | */ |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 868 | (void) commit_or_fallback(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 869 | |
| 870 | r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); |
| 871 | if (r) |
| 872 | return r; |
| 873 | |
| 874 | /* |
| 875 | * If we still have no space we set a flag to avoid |
| 876 | * doing all this checking and return -ENOSPC. |
| 877 | */ |
| 878 | if (!free_blocks) { |
| 879 | DMWARN("%s: no free space available.", |
| 880 | dm_device_name(pool->pool_md)); |
| 881 | spin_lock_irqsave(&pool->lock, flags); |
| 882 | pool->no_free_space = 1; |
| 883 | spin_unlock_irqrestore(&pool->lock, flags); |
| 884 | return -ENOSPC; |
| 885 | } |
| 886 | } |
| 887 | } |
| 888 | |
| 889 | r = dm_pool_alloc_data_block(pool->pmd, result); |
| 890 | if (r) |
| 891 | return r; |
| 892 | |
| 893 | return 0; |
| 894 | } |
| 895 | |
| 896 | /* |
| 897 | * If we have run out of space, queue bios until the device is |
| 898 | * resumed, presumably after having been reloaded with more space. |
| 899 | */ |
| 900 | static void retry_on_resume(struct bio *bio) |
| 901 | { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 902 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 903 | struct thin_c *tc = h->tc; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 904 | struct pool *pool = tc->pool; |
| 905 | unsigned long flags; |
| 906 | |
| 907 | spin_lock_irqsave(&pool->lock, flags); |
| 908 | bio_list_add(&pool->retry_on_resume_list, bio); |
| 909 | spin_unlock_irqrestore(&pool->lock, flags); |
| 910 | } |
| 911 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 912 | static void no_space(struct dm_bio_prison_cell *cell) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 913 | { |
| 914 | struct bio *bio; |
| 915 | struct bio_list bios; |
| 916 | |
| 917 | bio_list_init(&bios); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 918 | dm_cell_release(cell, &bios); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 919 | |
| 920 | while ((bio = bio_list_pop(&bios))) |
| 921 | retry_on_resume(bio); |
| 922 | } |
| 923 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 924 | static void process_discard(struct thin_c *tc, struct bio *bio) |
| 925 | { |
| 926 | int r; |
Mike Snitzer | c3a0ce2 | 2012-05-12 01:43:16 +0100 | [diff] [blame] | 927 | unsigned long flags; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 928 | struct pool *pool = tc->pool; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 929 | struct dm_bio_prison_cell *cell, *cell2; |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 930 | struct dm_cell_key key, key2; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 931 | dm_block_t block = get_bio_block(tc, bio); |
| 932 | struct dm_thin_lookup_result lookup_result; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 933 | struct dm_thin_new_mapping *m; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 934 | |
| 935 | build_virtual_key(tc->td, block, &key); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 936 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell)) |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 937 | return; |
| 938 | |
| 939 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); |
| 940 | switch (r) { |
| 941 | case 0: |
| 942 | /* |
| 943 | * Check nobody is fiddling with this pool block. This can |
| 944 | * happen if someone's in the process of breaking sharing |
| 945 | * on this block. |
| 946 | */ |
| 947 | build_data_key(tc->td, lookup_result.block, &key2); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 948 | if (dm_bio_detain(tc->pool->prison, &key2, bio, &cell2)) { |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 949 | cell_defer_no_holder(tc, cell); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 950 | break; |
| 951 | } |
| 952 | |
| 953 | if (io_overlaps_block(pool, bio)) { |
| 954 | /* |
| 955 | * IO may still be going to the destination block. We must |
| 956 | * quiesce before we can do the removal. |
| 957 | */ |
| 958 | m = get_next_mapping(pool); |
| 959 | m->tc = tc; |
Mike Snitzer | 17b7d63 | 2012-07-27 15:07:57 +0100 | [diff] [blame] | 960 | m->pass_discard = (!lookup_result.shared) && pool->pf.discard_passdown; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 961 | m->virt_block = block; |
| 962 | m->data_block = lookup_result.block; |
| 963 | m->cell = cell; |
| 964 | m->cell2 = cell2; |
| 965 | m->err = 0; |
| 966 | m->bio = bio; |
| 967 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 968 | if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list)) { |
Mike Snitzer | c3a0ce2 | 2012-05-12 01:43:16 +0100 | [diff] [blame] | 969 | spin_lock_irqsave(&pool->lock, flags); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 970 | list_add(&m->list, &pool->prepared_discards); |
Mike Snitzer | c3a0ce2 | 2012-05-12 01:43:16 +0100 | [diff] [blame] | 971 | spin_unlock_irqrestore(&pool->lock, flags); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 972 | wake_worker(pool); |
| 973 | } |
| 974 | } else { |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 975 | inc_all_io_entry(pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 976 | cell_defer_no_holder(tc, cell); |
| 977 | cell_defer_no_holder(tc, cell2); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 978 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 979 | /* |
Mikulas Patocka | 4929630 | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 980 | * The DM core makes sure that the discard doesn't span |
| 981 | * a block boundary. So we submit the discard of a |
| 982 | * partial block appropriately. |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 983 | */ |
Mikulas Patocka | 650d2a0 | 2012-07-20 14:25:05 +0100 | [diff] [blame] | 984 | if ((!lookup_result.shared) && pool->pf.discard_passdown) |
| 985 | remap_and_issue(tc, bio, lookup_result.block); |
| 986 | else |
| 987 | bio_endio(bio, 0); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 988 | } |
| 989 | break; |
| 990 | |
| 991 | case -ENODATA: |
| 992 | /* |
| 993 | * It isn't provisioned, just forget it. |
| 994 | */ |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 995 | cell_defer_no_holder(tc, cell); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 996 | bio_endio(bio, 0); |
| 997 | break; |
| 998 | |
| 999 | default: |
| 1000 | DMERR("discard: find block unexpectedly returned %d", r); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1001 | cell_defer_no_holder(tc, cell); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1002 | bio_io_error(bio); |
| 1003 | break; |
| 1004 | } |
| 1005 | } |
| 1006 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1007 | static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block, |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1008 | struct dm_cell_key *key, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1009 | struct dm_thin_lookup_result *lookup_result, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1010 | struct dm_bio_prison_cell *cell) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1011 | { |
| 1012 | int r; |
| 1013 | dm_block_t data_block; |
| 1014 | |
| 1015 | r = alloc_data_block(tc, &data_block); |
| 1016 | switch (r) { |
| 1017 | case 0: |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1018 | schedule_internal_copy(tc, block, lookup_result->block, |
| 1019 | data_block, cell, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1020 | break; |
| 1021 | |
| 1022 | case -ENOSPC: |
| 1023 | no_space(cell); |
| 1024 | break; |
| 1025 | |
| 1026 | default: |
| 1027 | DMERR("%s: alloc_data_block() failed, error = %d", __func__, r); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1028 | dm_cell_error(cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1029 | break; |
| 1030 | } |
| 1031 | } |
| 1032 | |
| 1033 | static void process_shared_bio(struct thin_c *tc, struct bio *bio, |
| 1034 | dm_block_t block, |
| 1035 | struct dm_thin_lookup_result *lookup_result) |
| 1036 | { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1037 | struct dm_bio_prison_cell *cell; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1038 | struct pool *pool = tc->pool; |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1039 | struct dm_cell_key key; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1040 | |
| 1041 | /* |
| 1042 | * If cell is already occupied, then sharing is already in the process |
| 1043 | * of being broken so we have nothing further to do here. |
| 1044 | */ |
| 1045 | build_data_key(tc->td, lookup_result->block, &key); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1046 | if (dm_bio_detain(pool->prison, &key, bio, &cell)) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1047 | return; |
| 1048 | |
Joe Thornber | 6004970 | 2012-07-27 15:08:06 +0100 | [diff] [blame] | 1049 | if (bio_data_dir(bio) == WRITE && bio->bi_size) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1050 | break_sharing(tc, bio, block, &key, lookup_result, cell); |
| 1051 | else { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1052 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1053 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1054 | h->shared_read_entry = dm_deferred_entry_inc(pool->shared_read_ds); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1055 | inc_all_io_entry(pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1056 | cell_defer_no_holder(tc, cell); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1057 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1058 | remap_and_issue(tc, bio, lookup_result->block); |
| 1059 | } |
| 1060 | } |
| 1061 | |
| 1062 | static void provision_block(struct thin_c *tc, struct bio *bio, dm_block_t block, |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1063 | struct dm_bio_prison_cell *cell) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1064 | { |
| 1065 | int r; |
| 1066 | dm_block_t data_block; |
| 1067 | |
| 1068 | /* |
| 1069 | * Remap empty bios (flushes) immediately, without provisioning. |
| 1070 | */ |
| 1071 | if (!bio->bi_size) { |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1072 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1073 | cell_defer_no_holder(tc, cell); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1074 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1075 | remap_and_issue(tc, bio, 0); |
| 1076 | return; |
| 1077 | } |
| 1078 | |
| 1079 | /* |
| 1080 | * Fill read bios with zeroes and complete them immediately. |
| 1081 | */ |
| 1082 | if (bio_data_dir(bio) == READ) { |
| 1083 | zero_fill_bio(bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1084 | cell_defer_no_holder(tc, cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1085 | bio_endio(bio, 0); |
| 1086 | return; |
| 1087 | } |
| 1088 | |
| 1089 | r = alloc_data_block(tc, &data_block); |
| 1090 | switch (r) { |
| 1091 | case 0: |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1092 | if (tc->origin_dev) |
| 1093 | schedule_external_copy(tc, block, data_block, cell, bio); |
| 1094 | else |
| 1095 | schedule_zero(tc, block, data_block, cell, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1096 | break; |
| 1097 | |
| 1098 | case -ENOSPC: |
| 1099 | no_space(cell); |
| 1100 | break; |
| 1101 | |
| 1102 | default: |
| 1103 | DMERR("%s: alloc_data_block() failed, error = %d", __func__, r); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1104 | set_pool_mode(tc->pool, PM_READ_ONLY); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1105 | dm_cell_error(cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1106 | break; |
| 1107 | } |
| 1108 | } |
| 1109 | |
| 1110 | static void process_bio(struct thin_c *tc, struct bio *bio) |
| 1111 | { |
| 1112 | int r; |
| 1113 | dm_block_t block = get_bio_block(tc, bio); |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1114 | struct dm_bio_prison_cell *cell; |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1115 | struct dm_cell_key key; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1116 | struct dm_thin_lookup_result lookup_result; |
| 1117 | |
| 1118 | /* |
| 1119 | * If cell is already occupied, then the block is already |
| 1120 | * being provisioned so we have nothing further to do here. |
| 1121 | */ |
| 1122 | build_virtual_key(tc->td, block, &key); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1123 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell)) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1124 | return; |
| 1125 | |
| 1126 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); |
| 1127 | switch (r) { |
| 1128 | case 0: |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1129 | if (lookup_result.shared) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1130 | process_shared_bio(tc, bio, block, &lookup_result); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1131 | cell_defer_no_holder(tc, cell); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1132 | } else { |
| 1133 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1134 | cell_defer_no_holder(tc, cell); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1135 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1136 | remap_and_issue(tc, bio, lookup_result.block); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1137 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1138 | break; |
| 1139 | |
| 1140 | case -ENODATA: |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1141 | if (bio_data_dir(bio) == READ && tc->origin_dev) { |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1142 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1143 | cell_defer_no_holder(tc, cell); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1144 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1145 | remap_to_origin_and_issue(tc, bio); |
| 1146 | } else |
| 1147 | provision_block(tc, bio, block, cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1148 | break; |
| 1149 | |
| 1150 | default: |
| 1151 | DMERR("dm_thin_find_block() failed, error = %d", r); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1152 | cell_defer_no_holder(tc, cell); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1153 | bio_io_error(bio); |
| 1154 | break; |
| 1155 | } |
| 1156 | } |
| 1157 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1158 | static void process_bio_read_only(struct thin_c *tc, struct bio *bio) |
| 1159 | { |
| 1160 | int r; |
| 1161 | int rw = bio_data_dir(bio); |
| 1162 | dm_block_t block = get_bio_block(tc, bio); |
| 1163 | struct dm_thin_lookup_result lookup_result; |
| 1164 | |
| 1165 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); |
| 1166 | switch (r) { |
| 1167 | case 0: |
| 1168 | if (lookup_result.shared && (rw == WRITE) && bio->bi_size) |
| 1169 | bio_io_error(bio); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1170 | else { |
| 1171 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1172 | remap_and_issue(tc, bio, lookup_result.block); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1173 | } |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1174 | break; |
| 1175 | |
| 1176 | case -ENODATA: |
| 1177 | if (rw != READ) { |
| 1178 | bio_io_error(bio); |
| 1179 | break; |
| 1180 | } |
| 1181 | |
| 1182 | if (tc->origin_dev) { |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1183 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1184 | remap_to_origin_and_issue(tc, bio); |
| 1185 | break; |
| 1186 | } |
| 1187 | |
| 1188 | zero_fill_bio(bio); |
| 1189 | bio_endio(bio, 0); |
| 1190 | break; |
| 1191 | |
| 1192 | default: |
| 1193 | DMERR("dm_thin_find_block() failed, error = %d", r); |
| 1194 | bio_io_error(bio); |
| 1195 | break; |
| 1196 | } |
| 1197 | } |
| 1198 | |
| 1199 | static void process_bio_fail(struct thin_c *tc, struct bio *bio) |
| 1200 | { |
| 1201 | bio_io_error(bio); |
| 1202 | } |
| 1203 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1204 | static int need_commit_due_to_time(struct pool *pool) |
| 1205 | { |
| 1206 | return jiffies < pool->last_commit_jiffies || |
| 1207 | jiffies > pool->last_commit_jiffies + COMMIT_PERIOD; |
| 1208 | } |
| 1209 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1210 | static void process_deferred_bios(struct pool *pool) |
| 1211 | { |
| 1212 | unsigned long flags; |
| 1213 | struct bio *bio; |
| 1214 | struct bio_list bios; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1215 | |
| 1216 | bio_list_init(&bios); |
| 1217 | |
| 1218 | spin_lock_irqsave(&pool->lock, flags); |
| 1219 | bio_list_merge(&bios, &pool->deferred_bios); |
| 1220 | bio_list_init(&pool->deferred_bios); |
| 1221 | spin_unlock_irqrestore(&pool->lock, flags); |
| 1222 | |
| 1223 | while ((bio = bio_list_pop(&bios))) { |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1224 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1225 | struct thin_c *tc = h->tc; |
| 1226 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1227 | /* |
| 1228 | * If we've got no free new_mapping structs, and processing |
| 1229 | * this bio might require one, we pause until there are some |
| 1230 | * prepared mappings to process. |
| 1231 | */ |
| 1232 | if (ensure_next_mapping(pool)) { |
| 1233 | spin_lock_irqsave(&pool->lock, flags); |
| 1234 | bio_list_merge(&pool->deferred_bios, &bios); |
| 1235 | spin_unlock_irqrestore(&pool->lock, flags); |
| 1236 | |
| 1237 | break; |
| 1238 | } |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1239 | |
| 1240 | if (bio->bi_rw & REQ_DISCARD) |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1241 | pool->process_discard(tc, bio); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1242 | else |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1243 | pool->process_bio(tc, bio); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1244 | } |
| 1245 | |
| 1246 | /* |
| 1247 | * If there are any deferred flush bios, we must commit |
| 1248 | * the metadata before issuing them. |
| 1249 | */ |
| 1250 | bio_list_init(&bios); |
| 1251 | spin_lock_irqsave(&pool->lock, flags); |
| 1252 | bio_list_merge(&bios, &pool->deferred_flush_bios); |
| 1253 | bio_list_init(&pool->deferred_flush_bios); |
| 1254 | spin_unlock_irqrestore(&pool->lock, flags); |
| 1255 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1256 | if (bio_list_empty(&bios) && !need_commit_due_to_time(pool)) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1257 | return; |
| 1258 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1259 | if (commit_or_fallback(pool)) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1260 | while ((bio = bio_list_pop(&bios))) |
| 1261 | bio_io_error(bio); |
| 1262 | return; |
| 1263 | } |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1264 | pool->last_commit_jiffies = jiffies; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1265 | |
| 1266 | while ((bio = bio_list_pop(&bios))) |
| 1267 | generic_make_request(bio); |
| 1268 | } |
| 1269 | |
| 1270 | static void do_worker(struct work_struct *ws) |
| 1271 | { |
| 1272 | struct pool *pool = container_of(ws, struct pool, worker); |
| 1273 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1274 | process_prepared(pool, &pool->prepared_mappings, &pool->process_prepared_mapping); |
| 1275 | process_prepared(pool, &pool->prepared_discards, &pool->process_prepared_discard); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1276 | process_deferred_bios(pool); |
| 1277 | } |
| 1278 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1279 | /* |
| 1280 | * We want to commit periodically so that not too much |
| 1281 | * unwritten data builds up. |
| 1282 | */ |
| 1283 | static void do_waker(struct work_struct *ws) |
| 1284 | { |
| 1285 | struct pool *pool = container_of(to_delayed_work(ws), struct pool, waker); |
| 1286 | wake_worker(pool); |
| 1287 | queue_delayed_work(pool->wq, &pool->waker, COMMIT_PERIOD); |
| 1288 | } |
| 1289 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1290 | /*----------------------------------------------------------------*/ |
| 1291 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1292 | static enum pool_mode get_pool_mode(struct pool *pool) |
| 1293 | { |
| 1294 | return pool->pf.mode; |
| 1295 | } |
| 1296 | |
| 1297 | static void set_pool_mode(struct pool *pool, enum pool_mode mode) |
| 1298 | { |
| 1299 | int r; |
| 1300 | |
| 1301 | pool->pf.mode = mode; |
| 1302 | |
| 1303 | switch (mode) { |
| 1304 | case PM_FAIL: |
| 1305 | DMERR("switching pool to failure mode"); |
| 1306 | pool->process_bio = process_bio_fail; |
| 1307 | pool->process_discard = process_bio_fail; |
| 1308 | pool->process_prepared_mapping = process_prepared_mapping_fail; |
| 1309 | pool->process_prepared_discard = process_prepared_discard_fail; |
| 1310 | break; |
| 1311 | |
| 1312 | case PM_READ_ONLY: |
| 1313 | DMERR("switching pool to read-only mode"); |
| 1314 | r = dm_pool_abort_metadata(pool->pmd); |
| 1315 | if (r) { |
| 1316 | DMERR("aborting transaction failed"); |
| 1317 | set_pool_mode(pool, PM_FAIL); |
| 1318 | } else { |
| 1319 | dm_pool_metadata_read_only(pool->pmd); |
| 1320 | pool->process_bio = process_bio_read_only; |
| 1321 | pool->process_discard = process_discard; |
| 1322 | pool->process_prepared_mapping = process_prepared_mapping_fail; |
| 1323 | pool->process_prepared_discard = process_prepared_discard_passdown; |
| 1324 | } |
| 1325 | break; |
| 1326 | |
| 1327 | case PM_WRITE: |
| 1328 | pool->process_bio = process_bio; |
| 1329 | pool->process_discard = process_discard; |
| 1330 | pool->process_prepared_mapping = process_prepared_mapping; |
| 1331 | pool->process_prepared_discard = process_prepared_discard; |
| 1332 | break; |
| 1333 | } |
| 1334 | } |
| 1335 | |
| 1336 | /*----------------------------------------------------------------*/ |
| 1337 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1338 | /* |
| 1339 | * Mapping functions. |
| 1340 | */ |
| 1341 | |
| 1342 | /* |
| 1343 | * Called only while mapping a thin bio to hand it over to the workqueue. |
| 1344 | */ |
| 1345 | static void thin_defer_bio(struct thin_c *tc, struct bio *bio) |
| 1346 | { |
| 1347 | unsigned long flags; |
| 1348 | struct pool *pool = tc->pool; |
| 1349 | |
| 1350 | spin_lock_irqsave(&pool->lock, flags); |
| 1351 | bio_list_add(&pool->deferred_bios, bio); |
| 1352 | spin_unlock_irqrestore(&pool->lock, flags); |
| 1353 | |
| 1354 | wake_worker(pool); |
| 1355 | } |
| 1356 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1357 | static struct dm_thin_endio_hook *thin_hook_bio(struct thin_c *tc, struct bio *bio) |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1358 | { |
| 1359 | struct pool *pool = tc->pool; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1360 | struct dm_thin_endio_hook *h = mempool_alloc(pool->endio_hook_pool, GFP_NOIO); |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1361 | |
| 1362 | h->tc = tc; |
| 1363 | h->shared_read_entry = NULL; |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1364 | h->all_io_entry = NULL; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1365 | h->overwrite_mapping = NULL; |
| 1366 | |
| 1367 | return h; |
| 1368 | } |
| 1369 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1370 | /* |
| 1371 | * Non-blocking function called from the thin target's map function. |
| 1372 | */ |
| 1373 | static int thin_bio_map(struct dm_target *ti, struct bio *bio, |
| 1374 | union map_info *map_context) |
| 1375 | { |
| 1376 | int r; |
| 1377 | struct thin_c *tc = ti->private; |
| 1378 | dm_block_t block = get_bio_block(tc, bio); |
| 1379 | struct dm_thin_device *td = tc->td; |
| 1380 | struct dm_thin_lookup_result result; |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1381 | struct dm_bio_prison_cell *cell1, *cell2; |
| 1382 | struct dm_cell_key key; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1383 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1384 | map_context->ptr = thin_hook_bio(tc, bio); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1385 | |
| 1386 | if (get_pool_mode(tc->pool) == PM_FAIL) { |
| 1387 | bio_io_error(bio); |
| 1388 | return DM_MAPIO_SUBMITTED; |
| 1389 | } |
| 1390 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1391 | if (bio->bi_rw & (REQ_DISCARD | REQ_FLUSH | REQ_FUA)) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1392 | thin_defer_bio(tc, bio); |
| 1393 | return DM_MAPIO_SUBMITTED; |
| 1394 | } |
| 1395 | |
| 1396 | r = dm_thin_find_block(td, block, 0, &result); |
| 1397 | |
| 1398 | /* |
| 1399 | * Note that we defer readahead too. |
| 1400 | */ |
| 1401 | switch (r) { |
| 1402 | case 0: |
| 1403 | if (unlikely(result.shared)) { |
| 1404 | /* |
| 1405 | * We have a race condition here between the |
| 1406 | * result.shared value returned by the lookup and |
| 1407 | * snapshot creation, which may cause new |
| 1408 | * sharing. |
| 1409 | * |
| 1410 | * To avoid this always quiesce the origin before |
| 1411 | * taking the snap. You want to do this anyway to |
| 1412 | * ensure a consistent application view |
| 1413 | * (i.e. lockfs). |
| 1414 | * |
| 1415 | * More distant ancestors are irrelevant. The |
| 1416 | * shared flag will be set in their case. |
| 1417 | */ |
| 1418 | thin_defer_bio(tc, bio); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1419 | return DM_MAPIO_SUBMITTED; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1420 | } |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1421 | |
| 1422 | build_virtual_key(tc->td, block, &key); |
| 1423 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell1)) |
| 1424 | return DM_MAPIO_SUBMITTED; |
| 1425 | |
| 1426 | build_data_key(tc->td, result.block, &key); |
| 1427 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell2)) { |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1428 | cell_defer_no_holder(tc, cell1); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1429 | return DM_MAPIO_SUBMITTED; |
| 1430 | } |
| 1431 | |
| 1432 | inc_all_io_entry(tc->pool, bio); |
Joe Thornber | f286ba0 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1433 | cell_defer_no_holder(tc, cell2); |
| 1434 | cell_defer_no_holder(tc, cell1); |
Joe Thornber | e808807 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 1435 | |
| 1436 | remap(tc, bio, result.block); |
| 1437 | return DM_MAPIO_REMAPPED; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1438 | |
| 1439 | case -ENODATA: |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1440 | if (get_pool_mode(tc->pool) == PM_READ_ONLY) { |
| 1441 | /* |
| 1442 | * This block isn't provisioned, and we have no way |
| 1443 | * of doing so. Just error it. |
| 1444 | */ |
| 1445 | bio_io_error(bio); |
Joe Thornber | 2aab385 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1446 | return DM_MAPIO_SUBMITTED; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1447 | } |
| 1448 | /* fall through */ |
| 1449 | |
| 1450 | case -EWOULDBLOCK: |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1451 | /* |
| 1452 | * In future, the failed dm_thin_find_block above could |
| 1453 | * provide the hint to load the metadata into cache. |
| 1454 | */ |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1455 | thin_defer_bio(tc, bio); |
Joe Thornber | 2aab385 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1456 | return DM_MAPIO_SUBMITTED; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1457 | |
| 1458 | default: |
| 1459 | /* |
| 1460 | * Must always call bio_io_error on failure. |
| 1461 | * dm_thin_find_block can fail with -EINVAL if the |
| 1462 | * pool is switched to fail-io mode. |
| 1463 | */ |
| 1464 | bio_io_error(bio); |
Joe Thornber | 2aab385 | 2012-12-21 20:23:33 +0000 | [diff] [blame] | 1465 | return DM_MAPIO_SUBMITTED; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1466 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1467 | } |
| 1468 | |
| 1469 | static int pool_is_congested(struct dm_target_callbacks *cb, int bdi_bits) |
| 1470 | { |
| 1471 | int r; |
| 1472 | unsigned long flags; |
| 1473 | struct pool_c *pt = container_of(cb, struct pool_c, callbacks); |
| 1474 | |
| 1475 | spin_lock_irqsave(&pt->pool->lock, flags); |
| 1476 | r = !bio_list_empty(&pt->pool->retry_on_resume_list); |
| 1477 | spin_unlock_irqrestore(&pt->pool->lock, flags); |
| 1478 | |
| 1479 | if (!r) { |
| 1480 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); |
| 1481 | r = bdi_congested(&q->backing_dev_info, bdi_bits); |
| 1482 | } |
| 1483 | |
| 1484 | return r; |
| 1485 | } |
| 1486 | |
| 1487 | static void __requeue_bios(struct pool *pool) |
| 1488 | { |
| 1489 | bio_list_merge(&pool->deferred_bios, &pool->retry_on_resume_list); |
| 1490 | bio_list_init(&pool->retry_on_resume_list); |
| 1491 | } |
| 1492 | |
| 1493 | /*---------------------------------------------------------------- |
| 1494 | * Binding of control targets to a pool object |
| 1495 | *--------------------------------------------------------------*/ |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1496 | static bool data_dev_supports_discard(struct pool_c *pt) |
| 1497 | { |
| 1498 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); |
| 1499 | |
| 1500 | return q && blk_queue_discard(q); |
| 1501 | } |
| 1502 | |
| 1503 | /* |
| 1504 | * If discard_passdown was enabled verify that the data device |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1505 | * supports discards. Disable discard_passdown if not. |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1506 | */ |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1507 | static void disable_passdown_if_not_supported(struct pool_c *pt) |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1508 | { |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1509 | struct pool *pool = pt->pool; |
| 1510 | struct block_device *data_bdev = pt->data_dev->bdev; |
| 1511 | struct queue_limits *data_limits = &bdev_get_queue(data_bdev)->limits; |
| 1512 | sector_t block_size = pool->sectors_per_block << SECTOR_SHIFT; |
| 1513 | const char *reason = NULL; |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1514 | char buf[BDEVNAME_SIZE]; |
| 1515 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1516 | if (!pt->adjusted_pf.discard_passdown) |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1517 | return; |
| 1518 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1519 | if (!data_dev_supports_discard(pt)) |
| 1520 | reason = "discard unsupported"; |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1521 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1522 | else if (data_limits->max_discard_sectors < pool->sectors_per_block) |
| 1523 | reason = "max discard sectors smaller than a block"; |
| 1524 | |
| 1525 | else if (data_limits->discard_granularity > block_size) |
| 1526 | reason = "discard granularity larger than a block"; |
| 1527 | |
| 1528 | else if (block_size & (data_limits->discard_granularity - 1)) |
| 1529 | reason = "discard granularity not a factor of block size"; |
| 1530 | |
| 1531 | if (reason) { |
| 1532 | DMWARN("Data device (%s) %s: Disabling discard passdown.", bdevname(data_bdev, buf), reason); |
| 1533 | pt->adjusted_pf.discard_passdown = false; |
| 1534 | } |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1535 | } |
| 1536 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1537 | static int bind_control_target(struct pool *pool, struct dm_target *ti) |
| 1538 | { |
| 1539 | struct pool_c *pt = ti->private; |
| 1540 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1541 | /* |
| 1542 | * We want to make sure that degraded pools are never upgraded. |
| 1543 | */ |
| 1544 | enum pool_mode old_mode = pool->pf.mode; |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1545 | enum pool_mode new_mode = pt->adjusted_pf.mode; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1546 | |
| 1547 | if (old_mode > new_mode) |
| 1548 | new_mode = old_mode; |
| 1549 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1550 | pool->ti = ti; |
| 1551 | pool->low_water_blocks = pt->low_water_blocks; |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1552 | pool->pf = pt->adjusted_pf; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1553 | |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1554 | set_pool_mode(pool, new_mode); |
Mike Snitzer | f402693 | 2012-05-19 01:01:01 +0100 | [diff] [blame] | 1555 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1556 | return 0; |
| 1557 | } |
| 1558 | |
| 1559 | static void unbind_control_target(struct pool *pool, struct dm_target *ti) |
| 1560 | { |
| 1561 | if (pool->ti == ti) |
| 1562 | pool->ti = NULL; |
| 1563 | } |
| 1564 | |
| 1565 | /*---------------------------------------------------------------- |
| 1566 | * Pool creation |
| 1567 | *--------------------------------------------------------------*/ |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1568 | /* Initialize pool features. */ |
| 1569 | static void pool_features_init(struct pool_features *pf) |
| 1570 | { |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1571 | pf->mode = PM_WRITE; |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1572 | pf->zero_new_blocks = true; |
| 1573 | pf->discard_enabled = true; |
| 1574 | pf->discard_passdown = true; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1575 | } |
| 1576 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1577 | static void __pool_destroy(struct pool *pool) |
| 1578 | { |
| 1579 | __pool_table_remove(pool); |
| 1580 | |
| 1581 | if (dm_pool_metadata_close(pool->pmd) < 0) |
| 1582 | DMWARN("%s: dm_pool_metadata_close() failed.", __func__); |
| 1583 | |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1584 | dm_bio_prison_destroy(pool->prison); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1585 | dm_kcopyd_client_destroy(pool->copier); |
| 1586 | |
| 1587 | if (pool->wq) |
| 1588 | destroy_workqueue(pool->wq); |
| 1589 | |
| 1590 | if (pool->next_mapping) |
| 1591 | mempool_free(pool->next_mapping, pool->mapping_pool); |
| 1592 | mempool_destroy(pool->mapping_pool); |
| 1593 | mempool_destroy(pool->endio_hook_pool); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1594 | dm_deferred_set_destroy(pool->shared_read_ds); |
| 1595 | dm_deferred_set_destroy(pool->all_io_ds); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1596 | kfree(pool); |
| 1597 | } |
| 1598 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1599 | static struct kmem_cache *_new_mapping_cache; |
| 1600 | static struct kmem_cache *_endio_hook_cache; |
| 1601 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1602 | static struct pool *pool_create(struct mapped_device *pool_md, |
| 1603 | struct block_device *metadata_dev, |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1604 | unsigned long block_size, |
| 1605 | int read_only, char **error) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1606 | { |
| 1607 | int r; |
| 1608 | void *err_p; |
| 1609 | struct pool *pool; |
| 1610 | struct dm_pool_metadata *pmd; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1611 | bool format_device = read_only ? false : true; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1612 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1613 | pmd = dm_pool_metadata_open(metadata_dev, block_size, format_device); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1614 | if (IS_ERR(pmd)) { |
| 1615 | *error = "Error creating metadata object"; |
| 1616 | return (struct pool *)pmd; |
| 1617 | } |
| 1618 | |
| 1619 | pool = kmalloc(sizeof(*pool), GFP_KERNEL); |
| 1620 | if (!pool) { |
| 1621 | *error = "Error allocating memory for pool"; |
| 1622 | err_p = ERR_PTR(-ENOMEM); |
| 1623 | goto bad_pool; |
| 1624 | } |
| 1625 | |
| 1626 | pool->pmd = pmd; |
| 1627 | pool->sectors_per_block = block_size; |
Mikulas Patocka | f9a8e0c | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 1628 | if (block_size & (block_size - 1)) |
| 1629 | pool->sectors_per_block_shift = -1; |
| 1630 | else |
| 1631 | pool->sectors_per_block_shift = __ffs(block_size); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1632 | pool->low_water_blocks = 0; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1633 | pool_features_init(&pool->pf); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1634 | pool->prison = dm_bio_prison_create(PRISON_CELLS); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1635 | if (!pool->prison) { |
| 1636 | *error = "Error creating pool's bio prison"; |
| 1637 | err_p = ERR_PTR(-ENOMEM); |
| 1638 | goto bad_prison; |
| 1639 | } |
| 1640 | |
| 1641 | pool->copier = dm_kcopyd_client_create(); |
| 1642 | if (IS_ERR(pool->copier)) { |
| 1643 | r = PTR_ERR(pool->copier); |
| 1644 | *error = "Error creating pool's kcopyd client"; |
| 1645 | err_p = ERR_PTR(r); |
| 1646 | goto bad_kcopyd_client; |
| 1647 | } |
| 1648 | |
| 1649 | /* |
| 1650 | * Create singlethreaded workqueue that will service all devices |
| 1651 | * that use this metadata. |
| 1652 | */ |
| 1653 | pool->wq = alloc_ordered_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM); |
| 1654 | if (!pool->wq) { |
| 1655 | *error = "Error creating pool's workqueue"; |
| 1656 | err_p = ERR_PTR(-ENOMEM); |
| 1657 | goto bad_wq; |
| 1658 | } |
| 1659 | |
| 1660 | INIT_WORK(&pool->worker, do_worker); |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1661 | INIT_DELAYED_WORK(&pool->waker, do_waker); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1662 | spin_lock_init(&pool->lock); |
| 1663 | bio_list_init(&pool->deferred_bios); |
| 1664 | bio_list_init(&pool->deferred_flush_bios); |
| 1665 | INIT_LIST_HEAD(&pool->prepared_mappings); |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1666 | INIT_LIST_HEAD(&pool->prepared_discards); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1667 | pool->low_water_triggered = 0; |
| 1668 | pool->no_free_space = 0; |
| 1669 | bio_list_init(&pool->retry_on_resume_list); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1670 | |
| 1671 | pool->shared_read_ds = dm_deferred_set_create(); |
| 1672 | if (!pool->shared_read_ds) { |
| 1673 | *error = "Error creating pool's shared read deferred set"; |
| 1674 | err_p = ERR_PTR(-ENOMEM); |
| 1675 | goto bad_shared_read_ds; |
| 1676 | } |
| 1677 | |
| 1678 | pool->all_io_ds = dm_deferred_set_create(); |
| 1679 | if (!pool->all_io_ds) { |
| 1680 | *error = "Error creating pool's all io deferred set"; |
| 1681 | err_p = ERR_PTR(-ENOMEM); |
| 1682 | goto bad_all_io_ds; |
| 1683 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1684 | |
| 1685 | pool->next_mapping = NULL; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1686 | pool->mapping_pool = mempool_create_slab_pool(MAPPING_POOL_SIZE, |
| 1687 | _new_mapping_cache); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1688 | if (!pool->mapping_pool) { |
| 1689 | *error = "Error creating pool's mapping mempool"; |
| 1690 | err_p = ERR_PTR(-ENOMEM); |
| 1691 | goto bad_mapping_pool; |
| 1692 | } |
| 1693 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 1694 | pool->endio_hook_pool = mempool_create_slab_pool(ENDIO_HOOK_POOL_SIZE, |
| 1695 | _endio_hook_cache); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1696 | if (!pool->endio_hook_pool) { |
| 1697 | *error = "Error creating pool's endio_hook mempool"; |
| 1698 | err_p = ERR_PTR(-ENOMEM); |
| 1699 | goto bad_endio_hook_pool; |
| 1700 | } |
| 1701 | pool->ref_count = 1; |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 1702 | pool->last_commit_jiffies = jiffies; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1703 | pool->pool_md = pool_md; |
| 1704 | pool->md_dev = metadata_dev; |
| 1705 | __pool_table_insert(pool); |
| 1706 | |
| 1707 | return pool; |
| 1708 | |
| 1709 | bad_endio_hook_pool: |
| 1710 | mempool_destroy(pool->mapping_pool); |
| 1711 | bad_mapping_pool: |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1712 | dm_deferred_set_destroy(pool->all_io_ds); |
| 1713 | bad_all_io_ds: |
| 1714 | dm_deferred_set_destroy(pool->shared_read_ds); |
| 1715 | bad_shared_read_ds: |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1716 | destroy_workqueue(pool->wq); |
| 1717 | bad_wq: |
| 1718 | dm_kcopyd_client_destroy(pool->copier); |
| 1719 | bad_kcopyd_client: |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 1720 | dm_bio_prison_destroy(pool->prison); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1721 | bad_prison: |
| 1722 | kfree(pool); |
| 1723 | bad_pool: |
| 1724 | if (dm_pool_metadata_close(pmd)) |
| 1725 | DMWARN("%s: dm_pool_metadata_close() failed.", __func__); |
| 1726 | |
| 1727 | return err_p; |
| 1728 | } |
| 1729 | |
| 1730 | static void __pool_inc(struct pool *pool) |
| 1731 | { |
| 1732 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 1733 | pool->ref_count++; |
| 1734 | } |
| 1735 | |
| 1736 | static void __pool_dec(struct pool *pool) |
| 1737 | { |
| 1738 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); |
| 1739 | BUG_ON(!pool->ref_count); |
| 1740 | if (!--pool->ref_count) |
| 1741 | __pool_destroy(pool); |
| 1742 | } |
| 1743 | |
| 1744 | static struct pool *__pool_find(struct mapped_device *pool_md, |
| 1745 | struct block_device *metadata_dev, |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1746 | unsigned long block_size, int read_only, |
| 1747 | char **error, int *created) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1748 | { |
| 1749 | struct pool *pool = __pool_table_lookup_metadata_dev(metadata_dev); |
| 1750 | |
| 1751 | if (pool) { |
Mike Snitzer | f09996c | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 1752 | if (pool->pool_md != pool_md) { |
| 1753 | *error = "metadata device already in use by a pool"; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1754 | return ERR_PTR(-EBUSY); |
Mike Snitzer | f09996c | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 1755 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1756 | __pool_inc(pool); |
| 1757 | |
| 1758 | } else { |
| 1759 | pool = __pool_table_lookup(pool_md); |
| 1760 | if (pool) { |
Mike Snitzer | f09996c | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 1761 | if (pool->md_dev != metadata_dev) { |
| 1762 | *error = "different pool cannot replace a pool"; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1763 | return ERR_PTR(-EINVAL); |
Mike Snitzer | f09996c | 2012-07-27 15:07:59 +0100 | [diff] [blame] | 1764 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1765 | __pool_inc(pool); |
| 1766 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1767 | } else { |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1768 | pool = pool_create(pool_md, metadata_dev, block_size, read_only, error); |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1769 | *created = 1; |
| 1770 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1771 | } |
| 1772 | |
| 1773 | return pool; |
| 1774 | } |
| 1775 | |
| 1776 | /*---------------------------------------------------------------- |
| 1777 | * Pool target methods |
| 1778 | *--------------------------------------------------------------*/ |
| 1779 | static void pool_dtr(struct dm_target *ti) |
| 1780 | { |
| 1781 | struct pool_c *pt = ti->private; |
| 1782 | |
| 1783 | mutex_lock(&dm_thin_pool_table.mutex); |
| 1784 | |
| 1785 | unbind_control_target(pt->pool, ti); |
| 1786 | __pool_dec(pt->pool); |
| 1787 | dm_put_device(ti, pt->metadata_dev); |
| 1788 | dm_put_device(ti, pt->data_dev); |
| 1789 | kfree(pt); |
| 1790 | |
| 1791 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 1792 | } |
| 1793 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1794 | static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf, |
| 1795 | struct dm_target *ti) |
| 1796 | { |
| 1797 | int r; |
| 1798 | unsigned argc; |
| 1799 | const char *arg_name; |
| 1800 | |
| 1801 | static struct dm_arg _args[] = { |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1802 | {0, 3, "Invalid number of pool feature arguments"}, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1803 | }; |
| 1804 | |
| 1805 | /* |
| 1806 | * No feature arguments supplied. |
| 1807 | */ |
| 1808 | if (!as->argc) |
| 1809 | return 0; |
| 1810 | |
| 1811 | r = dm_read_arg_group(_args, as, &argc, &ti->error); |
| 1812 | if (r) |
| 1813 | return -EINVAL; |
| 1814 | |
| 1815 | while (argc && !r) { |
| 1816 | arg_name = dm_shift_arg(as); |
| 1817 | argc--; |
| 1818 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1819 | if (!strcasecmp(arg_name, "skip_block_zeroing")) |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1820 | pf->zero_new_blocks = false; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1821 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1822 | else if (!strcasecmp(arg_name, "ignore_discard")) |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1823 | pf->discard_enabled = false; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1824 | |
| 1825 | else if (!strcasecmp(arg_name, "no_discard_passdown")) |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1826 | pf->discard_passdown = false; |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1827 | |
| 1828 | else if (!strcasecmp(arg_name, "read_only")) |
| 1829 | pf->mode = PM_READ_ONLY; |
| 1830 | |
| 1831 | else { |
| 1832 | ti->error = "Unrecognised pool feature requested"; |
| 1833 | r = -EINVAL; |
| 1834 | break; |
| 1835 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1836 | } |
| 1837 | |
| 1838 | return r; |
| 1839 | } |
| 1840 | |
| 1841 | /* |
| 1842 | * thin-pool <metadata dev> <data dev> |
| 1843 | * <data block size (sectors)> |
| 1844 | * <low water mark (blocks)> |
| 1845 | * [<#feature args> [<arg>]*] |
| 1846 | * |
| 1847 | * Optional feature arguments are: |
| 1848 | * skip_block_zeroing: skips the zeroing of newly-provisioned blocks. |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1849 | * ignore_discard: disable discard |
| 1850 | * no_discard_passdown: don't pass discards down to the data device |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1851 | */ |
| 1852 | static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) |
| 1853 | { |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1854 | int r, pool_created = 0; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1855 | struct pool_c *pt; |
| 1856 | struct pool *pool; |
| 1857 | struct pool_features pf; |
| 1858 | struct dm_arg_set as; |
| 1859 | struct dm_dev *data_dev; |
| 1860 | unsigned long block_size; |
| 1861 | dm_block_t low_water_blocks; |
| 1862 | struct dm_dev *metadata_dev; |
| 1863 | sector_t metadata_dev_size; |
Mike Snitzer | c4a69ec | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1864 | char b[BDEVNAME_SIZE]; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1865 | |
| 1866 | /* |
| 1867 | * FIXME Remove validation from scope of lock. |
| 1868 | */ |
| 1869 | mutex_lock(&dm_thin_pool_table.mutex); |
| 1870 | |
| 1871 | if (argc < 4) { |
| 1872 | ti->error = "Invalid argument count"; |
| 1873 | r = -EINVAL; |
| 1874 | goto out_unlock; |
| 1875 | } |
| 1876 | as.argc = argc; |
| 1877 | as.argv = argv; |
| 1878 | |
| 1879 | r = dm_get_device(ti, argv[0], FMODE_READ | FMODE_WRITE, &metadata_dev); |
| 1880 | if (r) { |
| 1881 | ti->error = "Error opening metadata block device"; |
| 1882 | goto out_unlock; |
| 1883 | } |
| 1884 | |
| 1885 | metadata_dev_size = i_size_read(metadata_dev->bdev->bd_inode) >> SECTOR_SHIFT; |
Mike Snitzer | c4a69ec | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 1886 | if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) |
| 1887 | DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.", |
| 1888 | bdevname(metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1889 | |
| 1890 | r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev); |
| 1891 | if (r) { |
| 1892 | ti->error = "Error getting data device"; |
| 1893 | goto out_metadata; |
| 1894 | } |
| 1895 | |
| 1896 | if (kstrtoul(argv[2], 10, &block_size) || !block_size || |
| 1897 | block_size < DATA_DEV_BLOCK_SIZE_MIN_SECTORS || |
| 1898 | block_size > DATA_DEV_BLOCK_SIZE_MAX_SECTORS || |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 1899 | block_size & (DATA_DEV_BLOCK_SIZE_MIN_SECTORS - 1)) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1900 | ti->error = "Invalid block size"; |
| 1901 | r = -EINVAL; |
| 1902 | goto out; |
| 1903 | } |
| 1904 | |
| 1905 | if (kstrtoull(argv[3], 10, (unsigned long long *)&low_water_blocks)) { |
| 1906 | ti->error = "Invalid low water mark"; |
| 1907 | r = -EINVAL; |
| 1908 | goto out; |
| 1909 | } |
| 1910 | |
| 1911 | /* |
| 1912 | * Set default pool features. |
| 1913 | */ |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1914 | pool_features_init(&pf); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1915 | |
| 1916 | dm_consume_args(&as, 4); |
| 1917 | r = parse_pool_features(&as, &pf, ti); |
| 1918 | if (r) |
| 1919 | goto out; |
| 1920 | |
| 1921 | pt = kzalloc(sizeof(*pt), GFP_KERNEL); |
| 1922 | if (!pt) { |
| 1923 | r = -ENOMEM; |
| 1924 | goto out; |
| 1925 | } |
| 1926 | |
| 1927 | pool = __pool_find(dm_table_get_md(ti->table), metadata_dev->bdev, |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 1928 | block_size, pf.mode == PM_READ_ONLY, &ti->error, &pool_created); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1929 | if (IS_ERR(pool)) { |
| 1930 | r = PTR_ERR(pool); |
| 1931 | goto out_free_pt; |
| 1932 | } |
| 1933 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1934 | /* |
| 1935 | * 'pool_created' reflects whether this is the first table load. |
| 1936 | * Top level discard support is not allowed to be changed after |
| 1937 | * initial load. This would require a pool reload to trigger thin |
| 1938 | * device changes. |
| 1939 | */ |
| 1940 | if (!pool_created && pf.discard_enabled != pool->pf.discard_enabled) { |
| 1941 | ti->error = "Discard support cannot be disabled once enabled"; |
| 1942 | r = -EINVAL; |
| 1943 | goto out_flags_changed; |
| 1944 | } |
| 1945 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1946 | pt->pool = pool; |
| 1947 | pt->ti = ti; |
| 1948 | pt->metadata_dev = metadata_dev; |
| 1949 | pt->data_dev = data_dev; |
| 1950 | pt->low_water_blocks = low_water_blocks; |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 1951 | pt->adjusted_pf = pt->requested_pf = pf; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1952 | ti->num_flush_requests = 1; |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1953 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1954 | /* |
| 1955 | * Only need to enable discards if the pool should pass |
| 1956 | * them down to the data device. The thin device's discard |
| 1957 | * processing will cause mappings to be removed from the btree. |
| 1958 | */ |
| 1959 | if (pf.discard_enabled && pf.discard_passdown) { |
| 1960 | ti->num_discard_requests = 1; |
Mike Snitzer | 9bc142d | 2012-09-26 23:45:46 +0100 | [diff] [blame] | 1961 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1962 | /* |
| 1963 | * Setting 'discards_supported' circumvents the normal |
| 1964 | * stacking of discard limits (this keeps the pool and |
| 1965 | * thin devices' discard limits consistent). |
| 1966 | */ |
Alasdair G Kergon | 0ac5548 | 2012-07-27 15:08:08 +0100 | [diff] [blame] | 1967 | ti->discards_supported = true; |
Mike Snitzer | 307615a | 2012-09-26 23:45:39 +0100 | [diff] [blame] | 1968 | ti->discard_zeroes_data_unsupported = true; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1969 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1970 | ti->private = pt; |
| 1971 | |
| 1972 | pt->callbacks.congested_fn = pool_is_congested; |
| 1973 | dm_table_add_target_callbacks(ti->table, &pt->callbacks); |
| 1974 | |
| 1975 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 1976 | |
| 1977 | return 0; |
| 1978 | |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 1979 | out_flags_changed: |
| 1980 | __pool_dec(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 1981 | out_free_pt: |
| 1982 | kfree(pt); |
| 1983 | out: |
| 1984 | dm_put_device(ti, data_dev); |
| 1985 | out_metadata: |
| 1986 | dm_put_device(ti, metadata_dev); |
| 1987 | out_unlock: |
| 1988 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 1989 | |
| 1990 | return r; |
| 1991 | } |
| 1992 | |
| 1993 | static int pool_map(struct dm_target *ti, struct bio *bio, |
| 1994 | union map_info *map_context) |
| 1995 | { |
| 1996 | int r; |
| 1997 | struct pool_c *pt = ti->private; |
| 1998 | struct pool *pool = pt->pool; |
| 1999 | unsigned long flags; |
| 2000 | |
| 2001 | /* |
| 2002 | * As this is a singleton target, ti->begin is always zero. |
| 2003 | */ |
| 2004 | spin_lock_irqsave(&pool->lock, flags); |
| 2005 | bio->bi_bdev = pt->data_dev->bdev; |
| 2006 | r = DM_MAPIO_REMAPPED; |
| 2007 | spin_unlock_irqrestore(&pool->lock, flags); |
| 2008 | |
| 2009 | return r; |
| 2010 | } |
| 2011 | |
| 2012 | /* |
| 2013 | * Retrieves the number of blocks of the data device from |
| 2014 | * the superblock and compares it to the actual device size, |
| 2015 | * thus resizing the data device in case it has grown. |
| 2016 | * |
| 2017 | * This both copes with opening preallocated data devices in the ctr |
| 2018 | * being followed by a resume |
| 2019 | * -and- |
| 2020 | * calling the resume method individually after userspace has |
| 2021 | * grown the data device in reaction to a table event. |
| 2022 | */ |
| 2023 | static int pool_preresume(struct dm_target *ti) |
| 2024 | { |
| 2025 | int r; |
| 2026 | struct pool_c *pt = ti->private; |
| 2027 | struct pool *pool = pt->pool; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2028 | sector_t data_size = ti->len; |
| 2029 | dm_block_t sb_data_size; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2030 | |
| 2031 | /* |
| 2032 | * Take control of the pool object. |
| 2033 | */ |
| 2034 | r = bind_control_target(pool, ti); |
| 2035 | if (r) |
| 2036 | return r; |
| 2037 | |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2038 | (void) sector_div(data_size, pool->sectors_per_block); |
| 2039 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2040 | r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size); |
| 2041 | if (r) { |
| 2042 | DMERR("failed to retrieve data device size"); |
| 2043 | return r; |
| 2044 | } |
| 2045 | |
| 2046 | if (data_size < sb_data_size) { |
| 2047 | DMERR("pool target too small, is %llu blocks (expected %llu)", |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2048 | (unsigned long long)data_size, sb_data_size); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2049 | return -EINVAL; |
| 2050 | |
| 2051 | } else if (data_size > sb_data_size) { |
| 2052 | r = dm_pool_resize_data_dev(pool->pmd, data_size); |
| 2053 | if (r) { |
| 2054 | DMERR("failed to resize data device"); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2055 | /* FIXME Stricter than necessary: Rollback transaction instead here */ |
| 2056 | set_pool_mode(pool, PM_READ_ONLY); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2057 | return r; |
| 2058 | } |
| 2059 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2060 | (void) commit_or_fallback(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2061 | } |
| 2062 | |
| 2063 | return 0; |
| 2064 | } |
| 2065 | |
| 2066 | static void pool_resume(struct dm_target *ti) |
| 2067 | { |
| 2068 | struct pool_c *pt = ti->private; |
| 2069 | struct pool *pool = pt->pool; |
| 2070 | unsigned long flags; |
| 2071 | |
| 2072 | spin_lock_irqsave(&pool->lock, flags); |
| 2073 | pool->low_water_triggered = 0; |
| 2074 | pool->no_free_space = 0; |
| 2075 | __requeue_bios(pool); |
| 2076 | spin_unlock_irqrestore(&pool->lock, flags); |
| 2077 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 2078 | do_waker(&pool->waker.work); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2079 | } |
| 2080 | |
| 2081 | static void pool_postsuspend(struct dm_target *ti) |
| 2082 | { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2083 | struct pool_c *pt = ti->private; |
| 2084 | struct pool *pool = pt->pool; |
| 2085 | |
Joe Thornber | 905e51b | 2012-03-28 18:41:27 +0100 | [diff] [blame] | 2086 | cancel_delayed_work(&pool->waker); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2087 | flush_workqueue(pool->wq); |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2088 | (void) commit_or_fallback(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2089 | } |
| 2090 | |
| 2091 | static int check_arg_count(unsigned argc, unsigned args_required) |
| 2092 | { |
| 2093 | if (argc != args_required) { |
| 2094 | DMWARN("Message received with %u arguments instead of %u.", |
| 2095 | argc, args_required); |
| 2096 | return -EINVAL; |
| 2097 | } |
| 2098 | |
| 2099 | return 0; |
| 2100 | } |
| 2101 | |
| 2102 | static int read_dev_id(char *arg, dm_thin_id *dev_id, int warning) |
| 2103 | { |
| 2104 | if (!kstrtoull(arg, 10, (unsigned long long *)dev_id) && |
| 2105 | *dev_id <= MAX_DEV_ID) |
| 2106 | return 0; |
| 2107 | |
| 2108 | if (warning) |
| 2109 | DMWARN("Message received with invalid device id: %s", arg); |
| 2110 | |
| 2111 | return -EINVAL; |
| 2112 | } |
| 2113 | |
| 2114 | static int process_create_thin_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2115 | { |
| 2116 | dm_thin_id dev_id; |
| 2117 | int r; |
| 2118 | |
| 2119 | r = check_arg_count(argc, 2); |
| 2120 | if (r) |
| 2121 | return r; |
| 2122 | |
| 2123 | r = read_dev_id(argv[1], &dev_id, 1); |
| 2124 | if (r) |
| 2125 | return r; |
| 2126 | |
| 2127 | r = dm_pool_create_thin(pool->pmd, dev_id); |
| 2128 | if (r) { |
| 2129 | DMWARN("Creation of new thinly-provisioned device with id %s failed.", |
| 2130 | argv[1]); |
| 2131 | return r; |
| 2132 | } |
| 2133 | |
| 2134 | return 0; |
| 2135 | } |
| 2136 | |
| 2137 | static int process_create_snap_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2138 | { |
| 2139 | dm_thin_id dev_id; |
| 2140 | dm_thin_id origin_dev_id; |
| 2141 | int r; |
| 2142 | |
| 2143 | r = check_arg_count(argc, 3); |
| 2144 | if (r) |
| 2145 | return r; |
| 2146 | |
| 2147 | r = read_dev_id(argv[1], &dev_id, 1); |
| 2148 | if (r) |
| 2149 | return r; |
| 2150 | |
| 2151 | r = read_dev_id(argv[2], &origin_dev_id, 1); |
| 2152 | if (r) |
| 2153 | return r; |
| 2154 | |
| 2155 | r = dm_pool_create_snap(pool->pmd, dev_id, origin_dev_id); |
| 2156 | if (r) { |
| 2157 | DMWARN("Creation of new snapshot %s of device %s failed.", |
| 2158 | argv[1], argv[2]); |
| 2159 | return r; |
| 2160 | } |
| 2161 | |
| 2162 | return 0; |
| 2163 | } |
| 2164 | |
| 2165 | static int process_delete_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2166 | { |
| 2167 | dm_thin_id dev_id; |
| 2168 | int r; |
| 2169 | |
| 2170 | r = check_arg_count(argc, 2); |
| 2171 | if (r) |
| 2172 | return r; |
| 2173 | |
| 2174 | r = read_dev_id(argv[1], &dev_id, 1); |
| 2175 | if (r) |
| 2176 | return r; |
| 2177 | |
| 2178 | r = dm_pool_delete_thin_device(pool->pmd, dev_id); |
| 2179 | if (r) |
| 2180 | DMWARN("Deletion of thin device %s failed.", argv[1]); |
| 2181 | |
| 2182 | return r; |
| 2183 | } |
| 2184 | |
| 2185 | static int process_set_transaction_id_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2186 | { |
| 2187 | dm_thin_id old_id, new_id; |
| 2188 | int r; |
| 2189 | |
| 2190 | r = check_arg_count(argc, 3); |
| 2191 | if (r) |
| 2192 | return r; |
| 2193 | |
| 2194 | if (kstrtoull(argv[1], 10, (unsigned long long *)&old_id)) { |
| 2195 | DMWARN("set_transaction_id message: Unrecognised id %s.", argv[1]); |
| 2196 | return -EINVAL; |
| 2197 | } |
| 2198 | |
| 2199 | if (kstrtoull(argv[2], 10, (unsigned long long *)&new_id)) { |
| 2200 | DMWARN("set_transaction_id message: Unrecognised new id %s.", argv[2]); |
| 2201 | return -EINVAL; |
| 2202 | } |
| 2203 | |
| 2204 | r = dm_pool_set_metadata_transaction_id(pool->pmd, old_id, new_id); |
| 2205 | if (r) { |
| 2206 | DMWARN("Failed to change transaction id from %s to %s.", |
| 2207 | argv[1], argv[2]); |
| 2208 | return r; |
| 2209 | } |
| 2210 | |
| 2211 | return 0; |
| 2212 | } |
| 2213 | |
Joe Thornber | cc8394d | 2012-06-03 00:30:01 +0100 | [diff] [blame] | 2214 | static int process_reserve_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2215 | { |
| 2216 | int r; |
| 2217 | |
| 2218 | r = check_arg_count(argc, 1); |
| 2219 | if (r) |
| 2220 | return r; |
| 2221 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2222 | (void) commit_or_fallback(pool); |
Joe Thornber | 0d200ae | 2012-07-03 12:55:31 +0100 | [diff] [blame] | 2223 | |
Joe Thornber | cc8394d | 2012-06-03 00:30:01 +0100 | [diff] [blame] | 2224 | r = dm_pool_reserve_metadata_snap(pool->pmd); |
| 2225 | if (r) |
| 2226 | DMWARN("reserve_metadata_snap message failed."); |
| 2227 | |
| 2228 | return r; |
| 2229 | } |
| 2230 | |
| 2231 | static int process_release_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool) |
| 2232 | { |
| 2233 | int r; |
| 2234 | |
| 2235 | r = check_arg_count(argc, 1); |
| 2236 | if (r) |
| 2237 | return r; |
| 2238 | |
| 2239 | r = dm_pool_release_metadata_snap(pool->pmd); |
| 2240 | if (r) |
| 2241 | DMWARN("release_metadata_snap message failed."); |
| 2242 | |
| 2243 | return r; |
| 2244 | } |
| 2245 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2246 | /* |
| 2247 | * Messages supported: |
| 2248 | * create_thin <dev_id> |
| 2249 | * create_snap <dev_id> <origin_id> |
| 2250 | * delete <dev_id> |
| 2251 | * trim <dev_id> <new_size_in_sectors> |
| 2252 | * set_transaction_id <current_trans_id> <new_trans_id> |
Joe Thornber | cc8394d | 2012-06-03 00:30:01 +0100 | [diff] [blame] | 2253 | * reserve_metadata_snap |
| 2254 | * release_metadata_snap |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2255 | */ |
| 2256 | static int pool_message(struct dm_target *ti, unsigned argc, char **argv) |
| 2257 | { |
| 2258 | int r = -EINVAL; |
| 2259 | struct pool_c *pt = ti->private; |
| 2260 | struct pool *pool = pt->pool; |
| 2261 | |
| 2262 | if (!strcasecmp(argv[0], "create_thin")) |
| 2263 | r = process_create_thin_mesg(argc, argv, pool); |
| 2264 | |
| 2265 | else if (!strcasecmp(argv[0], "create_snap")) |
| 2266 | r = process_create_snap_mesg(argc, argv, pool); |
| 2267 | |
| 2268 | else if (!strcasecmp(argv[0], "delete")) |
| 2269 | r = process_delete_mesg(argc, argv, pool); |
| 2270 | |
| 2271 | else if (!strcasecmp(argv[0], "set_transaction_id")) |
| 2272 | r = process_set_transaction_id_mesg(argc, argv, pool); |
| 2273 | |
Joe Thornber | cc8394d | 2012-06-03 00:30:01 +0100 | [diff] [blame] | 2274 | else if (!strcasecmp(argv[0], "reserve_metadata_snap")) |
| 2275 | r = process_reserve_metadata_snap_mesg(argc, argv, pool); |
| 2276 | |
| 2277 | else if (!strcasecmp(argv[0], "release_metadata_snap")) |
| 2278 | r = process_release_metadata_snap_mesg(argc, argv, pool); |
| 2279 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2280 | else |
| 2281 | DMWARN("Unrecognised thin pool target message received: %s", argv[0]); |
| 2282 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2283 | if (!r) |
| 2284 | (void) commit_or_fallback(pool); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2285 | |
| 2286 | return r; |
| 2287 | } |
| 2288 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2289 | static void emit_flags(struct pool_features *pf, char *result, |
| 2290 | unsigned sz, unsigned maxlen) |
| 2291 | { |
| 2292 | unsigned count = !pf->zero_new_blocks + !pf->discard_enabled + |
| 2293 | !pf->discard_passdown + (pf->mode == PM_READ_ONLY); |
| 2294 | DMEMIT("%u ", count); |
| 2295 | |
| 2296 | if (!pf->zero_new_blocks) |
| 2297 | DMEMIT("skip_block_zeroing "); |
| 2298 | |
| 2299 | if (!pf->discard_enabled) |
| 2300 | DMEMIT("ignore_discard "); |
| 2301 | |
| 2302 | if (!pf->discard_passdown) |
| 2303 | DMEMIT("no_discard_passdown "); |
| 2304 | |
| 2305 | if (pf->mode == PM_READ_ONLY) |
| 2306 | DMEMIT("read_only "); |
| 2307 | } |
| 2308 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2309 | /* |
| 2310 | * Status line is: |
| 2311 | * <transaction id> <used metadata sectors>/<total metadata sectors> |
| 2312 | * <used data sectors>/<total data sectors> <held metadata root> |
| 2313 | */ |
| 2314 | static int pool_status(struct dm_target *ti, status_type_t type, |
Alasdair G Kergon | 1f4e0ff | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2315 | unsigned status_flags, char *result, unsigned maxlen) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2316 | { |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2317 | int r; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2318 | unsigned sz = 0; |
| 2319 | uint64_t transaction_id; |
| 2320 | dm_block_t nr_free_blocks_data; |
| 2321 | dm_block_t nr_free_blocks_metadata; |
| 2322 | dm_block_t nr_blocks_data; |
| 2323 | dm_block_t nr_blocks_metadata; |
| 2324 | dm_block_t held_root; |
| 2325 | char buf[BDEVNAME_SIZE]; |
| 2326 | char buf2[BDEVNAME_SIZE]; |
| 2327 | struct pool_c *pt = ti->private; |
| 2328 | struct pool *pool = pt->pool; |
| 2329 | |
| 2330 | switch (type) { |
| 2331 | case STATUSTYPE_INFO: |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2332 | if (get_pool_mode(pool) == PM_FAIL) { |
| 2333 | DMEMIT("Fail"); |
| 2334 | break; |
| 2335 | } |
| 2336 | |
Alasdair G Kergon | 1f4e0ff | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2337 | /* Commit to ensure statistics aren't out-of-date */ |
| 2338 | if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti)) |
| 2339 | (void) commit_or_fallback(pool); |
| 2340 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2341 | r = dm_pool_get_metadata_transaction_id(pool->pmd, |
| 2342 | &transaction_id); |
| 2343 | if (r) |
| 2344 | return r; |
| 2345 | |
| 2346 | r = dm_pool_get_free_metadata_block_count(pool->pmd, |
| 2347 | &nr_free_blocks_metadata); |
| 2348 | if (r) |
| 2349 | return r; |
| 2350 | |
| 2351 | r = dm_pool_get_metadata_dev_size(pool->pmd, &nr_blocks_metadata); |
| 2352 | if (r) |
| 2353 | return r; |
| 2354 | |
| 2355 | r = dm_pool_get_free_block_count(pool->pmd, |
| 2356 | &nr_free_blocks_data); |
| 2357 | if (r) |
| 2358 | return r; |
| 2359 | |
| 2360 | r = dm_pool_get_data_dev_size(pool->pmd, &nr_blocks_data); |
| 2361 | if (r) |
| 2362 | return r; |
| 2363 | |
Joe Thornber | cc8394d | 2012-06-03 00:30:01 +0100 | [diff] [blame] | 2364 | r = dm_pool_get_metadata_snap(pool->pmd, &held_root); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2365 | if (r) |
| 2366 | return r; |
| 2367 | |
| 2368 | DMEMIT("%llu %llu/%llu %llu/%llu ", |
| 2369 | (unsigned long long)transaction_id, |
| 2370 | (unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata), |
| 2371 | (unsigned long long)nr_blocks_metadata, |
| 2372 | (unsigned long long)(nr_blocks_data - nr_free_blocks_data), |
| 2373 | (unsigned long long)nr_blocks_data); |
| 2374 | |
| 2375 | if (held_root) |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2376 | DMEMIT("%llu ", held_root); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2377 | else |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2378 | DMEMIT("- "); |
| 2379 | |
| 2380 | if (pool->pf.mode == PM_READ_ONLY) |
| 2381 | DMEMIT("ro "); |
| 2382 | else |
| 2383 | DMEMIT("rw "); |
| 2384 | |
Mike Snitzer | 018debe | 2012-12-21 20:23:32 +0000 | [diff] [blame] | 2385 | if (!pool->pf.discard_enabled) |
| 2386 | DMEMIT("ignore_discard"); |
| 2387 | else if (pool->pf.discard_passdown) |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2388 | DMEMIT("discard_passdown"); |
| 2389 | else |
| 2390 | DMEMIT("no_discard_passdown"); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2391 | |
| 2392 | break; |
| 2393 | |
| 2394 | case STATUSTYPE_TABLE: |
| 2395 | DMEMIT("%s %s %lu %llu ", |
| 2396 | format_dev_t(buf, pt->metadata_dev->bdev->bd_dev), |
| 2397 | format_dev_t(buf2, pt->data_dev->bdev->bd_dev), |
| 2398 | (unsigned long)pool->sectors_per_block, |
| 2399 | (unsigned long long)pt->low_water_blocks); |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2400 | emit_flags(&pt->requested_pf, result, sz, maxlen); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2401 | break; |
| 2402 | } |
| 2403 | |
| 2404 | return 0; |
| 2405 | } |
| 2406 | |
| 2407 | static int pool_iterate_devices(struct dm_target *ti, |
| 2408 | iterate_devices_callout_fn fn, void *data) |
| 2409 | { |
| 2410 | struct pool_c *pt = ti->private; |
| 2411 | |
| 2412 | return fn(ti, pt->data_dev, 0, ti->len, data); |
| 2413 | } |
| 2414 | |
| 2415 | static int pool_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
| 2416 | struct bio_vec *biovec, int max_size) |
| 2417 | { |
| 2418 | struct pool_c *pt = ti->private; |
| 2419 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); |
| 2420 | |
| 2421 | if (!q->merge_bvec_fn) |
| 2422 | return max_size; |
| 2423 | |
| 2424 | bvm->bi_bdev = pt->data_dev->bdev; |
| 2425 | |
| 2426 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); |
| 2427 | } |
| 2428 | |
Mike Snitzer | 28eed34 | 2012-10-12 21:02:07 +0100 | [diff] [blame] | 2429 | static bool block_size_is_power_of_two(struct pool *pool) |
| 2430 | { |
| 2431 | return pool->sectors_per_block_shift >= 0; |
| 2432 | } |
| 2433 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2434 | static void set_discard_limits(struct pool_c *pt, struct queue_limits *limits) |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2435 | { |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2436 | struct pool *pool = pt->pool; |
| 2437 | struct queue_limits *data_limits; |
| 2438 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2439 | limits->max_discard_sectors = pool->sectors_per_block; |
| 2440 | |
| 2441 | /* |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2442 | * discard_granularity is just a hint, and not enforced. |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2443 | */ |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2444 | if (pt->adjusted_pf.discard_passdown) { |
| 2445 | data_limits = &bdev_get_queue(pt->data_dev->bdev)->limits; |
| 2446 | limits->discard_granularity = data_limits->discard_granularity; |
Mike Snitzer | 28eed34 | 2012-10-12 21:02:07 +0100 | [diff] [blame] | 2447 | } else if (block_size_is_power_of_two(pool)) |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2448 | limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT; |
Mike Snitzer | 28eed34 | 2012-10-12 21:02:07 +0100 | [diff] [blame] | 2449 | else |
| 2450 | /* |
| 2451 | * Use largest power of 2 that is a factor of sectors_per_block |
| 2452 | * but at least DATA_DEV_BLOCK_SIZE_MIN_SECTORS. |
| 2453 | */ |
| 2454 | limits->discard_granularity = max(1 << (ffs(pool->sectors_per_block) - 1), |
| 2455 | DATA_DEV_BLOCK_SIZE_MIN_SECTORS) << SECTOR_SHIFT; |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2456 | } |
| 2457 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2458 | static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits) |
| 2459 | { |
| 2460 | struct pool_c *pt = ti->private; |
| 2461 | struct pool *pool = pt->pool; |
| 2462 | |
| 2463 | blk_limits_io_min(limits, 0); |
| 2464 | blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT); |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2465 | |
| 2466 | /* |
| 2467 | * pt->adjusted_pf is a staging area for the actual features to use. |
| 2468 | * They get transferred to the live pool in bind_control_target() |
| 2469 | * called from pool_preresume(). |
| 2470 | */ |
| 2471 | if (!pt->adjusted_pf.discard_enabled) |
| 2472 | return; |
| 2473 | |
| 2474 | disable_passdown_if_not_supported(pt); |
| 2475 | |
| 2476 | set_discard_limits(pt, limits); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2477 | } |
| 2478 | |
| 2479 | static struct target_type pool_target = { |
| 2480 | .name = "thin-pool", |
| 2481 | .features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE | |
| 2482 | DM_TARGET_IMMUTABLE, |
Mike Snitzer | 018debe | 2012-12-21 20:23:32 +0000 | [diff] [blame] | 2483 | .version = {1, 6, 0}, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2484 | .module = THIS_MODULE, |
| 2485 | .ctr = pool_ctr, |
| 2486 | .dtr = pool_dtr, |
| 2487 | .map = pool_map, |
| 2488 | .postsuspend = pool_postsuspend, |
| 2489 | .preresume = pool_preresume, |
| 2490 | .resume = pool_resume, |
| 2491 | .message = pool_message, |
| 2492 | .status = pool_status, |
| 2493 | .merge = pool_merge, |
| 2494 | .iterate_devices = pool_iterate_devices, |
| 2495 | .io_hints = pool_io_hints, |
| 2496 | }; |
| 2497 | |
| 2498 | /*---------------------------------------------------------------- |
| 2499 | * Thin target methods |
| 2500 | *--------------------------------------------------------------*/ |
| 2501 | static void thin_dtr(struct dm_target *ti) |
| 2502 | { |
| 2503 | struct thin_c *tc = ti->private; |
| 2504 | |
| 2505 | mutex_lock(&dm_thin_pool_table.mutex); |
| 2506 | |
| 2507 | __pool_dec(tc->pool); |
| 2508 | dm_pool_close_thin_device(tc->td); |
| 2509 | dm_put_device(ti, tc->pool_dev); |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2510 | if (tc->origin_dev) |
| 2511 | dm_put_device(ti, tc->origin_dev); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2512 | kfree(tc); |
| 2513 | |
| 2514 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 2515 | } |
| 2516 | |
| 2517 | /* |
| 2518 | * Thin target parameters: |
| 2519 | * |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2520 | * <pool_dev> <dev_id> [origin_dev] |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2521 | * |
| 2522 | * pool_dev: the path to the pool (eg, /dev/mapper/my_pool) |
| 2523 | * dev_id: the internal device identifier |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2524 | * origin_dev: a device external to the pool that should act as the origin |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 2525 | * |
| 2526 | * If the pool device has discards disabled, they get disabled for the thin |
| 2527 | * device as well. |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2528 | */ |
| 2529 | static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) |
| 2530 | { |
| 2531 | int r; |
| 2532 | struct thin_c *tc; |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2533 | struct dm_dev *pool_dev, *origin_dev; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2534 | struct mapped_device *pool_md; |
| 2535 | |
| 2536 | mutex_lock(&dm_thin_pool_table.mutex); |
| 2537 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2538 | if (argc != 2 && argc != 3) { |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2539 | ti->error = "Invalid argument count"; |
| 2540 | r = -EINVAL; |
| 2541 | goto out_unlock; |
| 2542 | } |
| 2543 | |
| 2544 | tc = ti->private = kzalloc(sizeof(*tc), GFP_KERNEL); |
| 2545 | if (!tc) { |
| 2546 | ti->error = "Out of memory"; |
| 2547 | r = -ENOMEM; |
| 2548 | goto out_unlock; |
| 2549 | } |
| 2550 | |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2551 | if (argc == 3) { |
| 2552 | r = dm_get_device(ti, argv[2], FMODE_READ, &origin_dev); |
| 2553 | if (r) { |
| 2554 | ti->error = "Error opening origin device"; |
| 2555 | goto bad_origin_dev; |
| 2556 | } |
| 2557 | tc->origin_dev = origin_dev; |
| 2558 | } |
| 2559 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2560 | r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &pool_dev); |
| 2561 | if (r) { |
| 2562 | ti->error = "Error opening pool device"; |
| 2563 | goto bad_pool_dev; |
| 2564 | } |
| 2565 | tc->pool_dev = pool_dev; |
| 2566 | |
| 2567 | if (read_dev_id(argv[1], (unsigned long long *)&tc->dev_id, 0)) { |
| 2568 | ti->error = "Invalid device id"; |
| 2569 | r = -EINVAL; |
| 2570 | goto bad_common; |
| 2571 | } |
| 2572 | |
| 2573 | pool_md = dm_get_md(tc->pool_dev->bdev->bd_dev); |
| 2574 | if (!pool_md) { |
| 2575 | ti->error = "Couldn't get pool mapped device"; |
| 2576 | r = -EINVAL; |
| 2577 | goto bad_common; |
| 2578 | } |
| 2579 | |
| 2580 | tc->pool = __pool_table_lookup(pool_md); |
| 2581 | if (!tc->pool) { |
| 2582 | ti->error = "Couldn't find pool object"; |
| 2583 | r = -EINVAL; |
| 2584 | goto bad_pool_lookup; |
| 2585 | } |
| 2586 | __pool_inc(tc->pool); |
| 2587 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2588 | if (get_pool_mode(tc->pool) == PM_FAIL) { |
| 2589 | ti->error = "Couldn't open thin device, Pool is in fail mode"; |
| 2590 | goto bad_thin_open; |
| 2591 | } |
| 2592 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2593 | r = dm_pool_open_thin_device(tc->pool->pmd, tc->dev_id, &tc->td); |
| 2594 | if (r) { |
| 2595 | ti->error = "Couldn't open thin internal device"; |
| 2596 | goto bad_thin_open; |
| 2597 | } |
| 2598 | |
Mike Snitzer | 542f903 | 2012-07-27 15:08:00 +0100 | [diff] [blame] | 2599 | r = dm_set_target_max_io_len(ti, tc->pool->sectors_per_block); |
| 2600 | if (r) |
| 2601 | goto bad_thin_open; |
| 2602 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2603 | ti->num_flush_requests = 1; |
Joe Thornber | 16ad3d1 | 2012-07-27 15:08:07 +0100 | [diff] [blame] | 2604 | ti->flush_supported = true; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 2605 | |
| 2606 | /* In case the pool supports discards, pass them on. */ |
| 2607 | if (tc->pool->pf.discard_enabled) { |
Alasdair G Kergon | 0ac5548 | 2012-07-27 15:08:08 +0100 | [diff] [blame] | 2608 | ti->discards_supported = true; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 2609 | ti->num_discard_requests = 1; |
Alasdair G Kergon | 0ac5548 | 2012-07-27 15:08:08 +0100 | [diff] [blame] | 2610 | ti->discard_zeroes_data_unsupported = true; |
Mikulas Patocka | 4929630 | 2012-07-27 15:08:03 +0100 | [diff] [blame] | 2611 | /* Discard requests must be split on a block boundary */ |
Alasdair G Kergon | 0ac5548 | 2012-07-27 15:08:08 +0100 | [diff] [blame] | 2612 | ti->split_discard_requests = true; |
Joe Thornber | 67e2e2b | 2012-03-28 18:41:29 +0100 | [diff] [blame] | 2613 | } |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2614 | |
| 2615 | dm_put(pool_md); |
| 2616 | |
| 2617 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 2618 | |
| 2619 | return 0; |
| 2620 | |
| 2621 | bad_thin_open: |
| 2622 | __pool_dec(tc->pool); |
| 2623 | bad_pool_lookup: |
| 2624 | dm_put(pool_md); |
| 2625 | bad_common: |
| 2626 | dm_put_device(ti, tc->pool_dev); |
| 2627 | bad_pool_dev: |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2628 | if (tc->origin_dev) |
| 2629 | dm_put_device(ti, tc->origin_dev); |
| 2630 | bad_origin_dev: |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2631 | kfree(tc); |
| 2632 | out_unlock: |
| 2633 | mutex_unlock(&dm_thin_pool_table.mutex); |
| 2634 | |
| 2635 | return r; |
| 2636 | } |
| 2637 | |
| 2638 | static int thin_map(struct dm_target *ti, struct bio *bio, |
| 2639 | union map_info *map_context) |
| 2640 | { |
Alasdair G Kergon | 6efd6e8 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2641 | bio->bi_sector = dm_target_offset(ti, bio->bi_sector); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2642 | |
| 2643 | return thin_bio_map(ti, bio, map_context); |
| 2644 | } |
| 2645 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2646 | static int thin_endio(struct dm_target *ti, |
| 2647 | struct bio *bio, int err, |
| 2648 | union map_info *map_context) |
| 2649 | { |
| 2650 | unsigned long flags; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2651 | struct dm_thin_endio_hook *h = map_context->ptr; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2652 | struct list_head work; |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2653 | struct dm_thin_new_mapping *m, *tmp; |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2654 | struct pool *pool = h->tc->pool; |
| 2655 | |
| 2656 | if (h->shared_read_entry) { |
| 2657 | INIT_LIST_HEAD(&work); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 2658 | dm_deferred_entry_dec(h->shared_read_entry, &work); |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2659 | |
| 2660 | spin_lock_irqsave(&pool->lock, flags); |
| 2661 | list_for_each_entry_safe(m, tmp, &work, list) { |
| 2662 | list_del(&m->list); |
| 2663 | m->quiesced = 1; |
| 2664 | __maybe_add_mapping(m); |
| 2665 | } |
| 2666 | spin_unlock_irqrestore(&pool->lock, flags); |
| 2667 | } |
| 2668 | |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2669 | if (h->all_io_entry) { |
| 2670 | INIT_LIST_HEAD(&work); |
Mike Snitzer | 44feb38 | 2012-10-12 21:02:10 +0100 | [diff] [blame] | 2671 | dm_deferred_entry_dec(h->all_io_entry, &work); |
Joe Thornber | 563af18 | 2012-12-21 20:23:31 +0000 | [diff] [blame] | 2672 | if (!list_empty(&work)) { |
| 2673 | spin_lock_irqsave(&pool->lock, flags); |
| 2674 | list_for_each_entry_safe(m, tmp, &work, list) |
| 2675 | list_add(&m->list, &pool->prepared_discards); |
| 2676 | spin_unlock_irqrestore(&pool->lock, flags); |
| 2677 | wake_worker(pool); |
| 2678 | } |
Joe Thornber | 104655f | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2679 | } |
| 2680 | |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2681 | mempool_free(h, pool->endio_hook_pool); |
| 2682 | |
| 2683 | return 0; |
| 2684 | } |
| 2685 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2686 | static void thin_postsuspend(struct dm_target *ti) |
| 2687 | { |
| 2688 | if (dm_noflush_suspending(ti)) |
| 2689 | requeue_io((struct thin_c *)ti->private); |
| 2690 | } |
| 2691 | |
| 2692 | /* |
| 2693 | * <nr mapped sectors> <highest mapped sector> |
| 2694 | */ |
| 2695 | static int thin_status(struct dm_target *ti, status_type_t type, |
Alasdair G Kergon | 1f4e0ff | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2696 | unsigned status_flags, char *result, unsigned maxlen) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2697 | { |
| 2698 | int r; |
| 2699 | ssize_t sz = 0; |
| 2700 | dm_block_t mapped, highest; |
| 2701 | char buf[BDEVNAME_SIZE]; |
| 2702 | struct thin_c *tc = ti->private; |
| 2703 | |
Joe Thornber | e49e582 | 2012-07-27 15:08:16 +0100 | [diff] [blame] | 2704 | if (get_pool_mode(tc->pool) == PM_FAIL) { |
| 2705 | DMEMIT("Fail"); |
| 2706 | return 0; |
| 2707 | } |
| 2708 | |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2709 | if (!tc->td) |
| 2710 | DMEMIT("-"); |
| 2711 | else { |
| 2712 | switch (type) { |
| 2713 | case STATUSTYPE_INFO: |
| 2714 | r = dm_thin_get_mapped_count(tc->td, &mapped); |
| 2715 | if (r) |
| 2716 | return r; |
| 2717 | |
| 2718 | r = dm_thin_get_highest_mapped_block(tc->td, &highest); |
| 2719 | if (r < 0) |
| 2720 | return r; |
| 2721 | |
| 2722 | DMEMIT("%llu ", mapped * tc->pool->sectors_per_block); |
| 2723 | if (r) |
| 2724 | DMEMIT("%llu", ((highest + 1) * |
| 2725 | tc->pool->sectors_per_block) - 1); |
| 2726 | else |
| 2727 | DMEMIT("-"); |
| 2728 | break; |
| 2729 | |
| 2730 | case STATUSTYPE_TABLE: |
| 2731 | DMEMIT("%s %lu", |
| 2732 | format_dev_t(buf, tc->pool_dev->bdev->bd_dev), |
| 2733 | (unsigned long) tc->dev_id); |
Joe Thornber | 2dd9c25 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2734 | if (tc->origin_dev) |
| 2735 | DMEMIT(" %s", format_dev_t(buf, tc->origin_dev->bdev->bd_dev)); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2736 | break; |
| 2737 | } |
| 2738 | } |
| 2739 | |
| 2740 | return 0; |
| 2741 | } |
| 2742 | |
| 2743 | static int thin_iterate_devices(struct dm_target *ti, |
| 2744 | iterate_devices_callout_fn fn, void *data) |
| 2745 | { |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2746 | sector_t blocks; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2747 | struct thin_c *tc = ti->private; |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2748 | struct pool *pool = tc->pool; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2749 | |
| 2750 | /* |
| 2751 | * We can't call dm_pool_get_data_dev_size() since that blocks. So |
| 2752 | * we follow a more convoluted path through to the pool's target. |
| 2753 | */ |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2754 | if (!pool->ti) |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2755 | return 0; /* nothing is bound */ |
| 2756 | |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2757 | blocks = pool->ti->len; |
| 2758 | (void) sector_div(blocks, pool->sectors_per_block); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2759 | if (blocks) |
Mike Snitzer | 55f2b8b | 2012-07-27 15:08:02 +0100 | [diff] [blame] | 2760 | return fn(ti, tc->pool_dev, 0, pool->sectors_per_block * blocks, data); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2761 | |
| 2762 | return 0; |
| 2763 | } |
| 2764 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2765 | /* |
| 2766 | * A thin device always inherits its queue limits from its pool. |
| 2767 | */ |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2768 | static void thin_io_hints(struct dm_target *ti, struct queue_limits *limits) |
| 2769 | { |
| 2770 | struct thin_c *tc = ti->private; |
| 2771 | |
Mike Snitzer | 0424caa | 2012-09-26 23:45:47 +0100 | [diff] [blame] | 2772 | *limits = bdev_get_queue(tc->pool_dev->bdev)->limits; |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2773 | } |
| 2774 | |
| 2775 | static struct target_type thin_target = { |
| 2776 | .name = "thin", |
Mike Snitzer | 4f81a41 | 2012-10-12 21:02:13 +0100 | [diff] [blame] | 2777 | .version = {1, 5, 0}, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2778 | .module = THIS_MODULE, |
| 2779 | .ctr = thin_ctr, |
| 2780 | .dtr = thin_dtr, |
| 2781 | .map = thin_map, |
Joe Thornber | eb2aa48 | 2012-03-28 18:41:28 +0100 | [diff] [blame] | 2782 | .end_io = thin_endio, |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2783 | .postsuspend = thin_postsuspend, |
| 2784 | .status = thin_status, |
| 2785 | .iterate_devices = thin_iterate_devices, |
| 2786 | .io_hints = thin_io_hints, |
| 2787 | }; |
| 2788 | |
| 2789 | /*----------------------------------------------------------------*/ |
| 2790 | |
| 2791 | static int __init dm_thin_init(void) |
| 2792 | { |
| 2793 | int r; |
| 2794 | |
| 2795 | pool_table_init(); |
| 2796 | |
| 2797 | r = dm_register_target(&thin_target); |
| 2798 | if (r) |
| 2799 | return r; |
| 2800 | |
| 2801 | r = dm_register_target(&pool_target); |
| 2802 | if (r) |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2803 | goto bad_pool_target; |
| 2804 | |
| 2805 | r = -ENOMEM; |
| 2806 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2807 | _new_mapping_cache = KMEM_CACHE(dm_thin_new_mapping, 0); |
| 2808 | if (!_new_mapping_cache) |
| 2809 | goto bad_new_mapping_cache; |
| 2810 | |
| 2811 | _endio_hook_cache = KMEM_CACHE(dm_thin_endio_hook, 0); |
| 2812 | if (!_endio_hook_cache) |
| 2813 | goto bad_endio_hook_cache; |
| 2814 | |
| 2815 | return 0; |
| 2816 | |
| 2817 | bad_endio_hook_cache: |
| 2818 | kmem_cache_destroy(_new_mapping_cache); |
| 2819 | bad_new_mapping_cache: |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2820 | dm_unregister_target(&pool_target); |
| 2821 | bad_pool_target: |
| 2822 | dm_unregister_target(&thin_target); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2823 | |
| 2824 | return r; |
| 2825 | } |
| 2826 | |
| 2827 | static void dm_thin_exit(void) |
| 2828 | { |
| 2829 | dm_unregister_target(&thin_target); |
| 2830 | dm_unregister_target(&pool_target); |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2831 | |
Mike Snitzer | a24c256 | 2012-06-03 00:30:00 +0100 | [diff] [blame] | 2832 | kmem_cache_destroy(_new_mapping_cache); |
| 2833 | kmem_cache_destroy(_endio_hook_cache); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2834 | } |
| 2835 | |
| 2836 | module_init(dm_thin_init); |
| 2837 | module_exit(dm_thin_exit); |
| 2838 | |
Alasdair G Kergon | 7cab8bf | 2012-05-12 01:43:19 +0100 | [diff] [blame] | 2839 | MODULE_DESCRIPTION(DM_NAME " thin provisioning target"); |
Joe Thornber | 991d9fa | 2011-10-31 20:21:18 +0000 | [diff] [blame] | 2840 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); |
| 2841 | MODULE_LICENSE("GPL"); |