Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 Red Hat. All rights reserved. |
| 3 | * |
| 4 | * This file is released under the GPL. |
| 5 | */ |
| 6 | |
| 7 | #include "dm.h" |
| 8 | #include "dm-bio-prison.h" |
Darrick J. Wong | b844fe6 | 2013-04-05 15:36:32 +0100 | [diff] [blame] | 9 | #include "dm-bio-record.h" |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 10 | #include "dm-cache-metadata.h" |
| 11 | |
| 12 | #include <linux/dm-io.h> |
| 13 | #include <linux/dm-kcopyd.h> |
Manuel Schölling | 0f30af9 | 2014-05-22 22:42:37 +0200 | [diff] [blame] | 14 | #include <linux/jiffies.h> |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 15 | #include <linux/init.h> |
| 16 | #include <linux/mempool.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/slab.h> |
| 19 | #include <linux/vmalloc.h> |
| 20 | |
| 21 | #define DM_MSG_PREFIX "cache" |
| 22 | |
| 23 | DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(cache_copy_throttle, |
| 24 | "A percentage of time allocated for copying to and/or from cache"); |
| 25 | |
| 26 | /*----------------------------------------------------------------*/ |
| 27 | |
Joe Thornber | 77289d3 | 2015-05-15 13:45:30 +0100 | [diff] [blame] | 28 | #define IOT_RESOLUTION 4 |
| 29 | |
| 30 | struct io_tracker { |
| 31 | spinlock_t lock; |
| 32 | |
| 33 | /* |
| 34 | * Sectors of in-flight IO. |
| 35 | */ |
| 36 | sector_t in_flight; |
| 37 | |
| 38 | /* |
| 39 | * The time, in jiffies, when this device became idle (if it is |
| 40 | * indeed idle). |
| 41 | */ |
| 42 | unsigned long idle_time; |
| 43 | unsigned long last_update_time; |
| 44 | }; |
| 45 | |
| 46 | static void iot_init(struct io_tracker *iot) |
| 47 | { |
| 48 | spin_lock_init(&iot->lock); |
| 49 | iot->in_flight = 0ul; |
| 50 | iot->idle_time = 0ul; |
| 51 | iot->last_update_time = jiffies; |
| 52 | } |
| 53 | |
| 54 | static bool __iot_idle_for(struct io_tracker *iot, unsigned long jifs) |
| 55 | { |
| 56 | if (iot->in_flight) |
| 57 | return false; |
| 58 | |
| 59 | return time_after(jiffies, iot->idle_time + jifs); |
| 60 | } |
| 61 | |
| 62 | static bool iot_idle_for(struct io_tracker *iot, unsigned long jifs) |
| 63 | { |
| 64 | bool r; |
| 65 | unsigned long flags; |
| 66 | |
| 67 | spin_lock_irqsave(&iot->lock, flags); |
| 68 | r = __iot_idle_for(iot, jifs); |
| 69 | spin_unlock_irqrestore(&iot->lock, flags); |
| 70 | |
| 71 | return r; |
| 72 | } |
| 73 | |
| 74 | static void iot_io_begin(struct io_tracker *iot, sector_t len) |
| 75 | { |
| 76 | unsigned long flags; |
| 77 | |
| 78 | spin_lock_irqsave(&iot->lock, flags); |
| 79 | iot->in_flight += len; |
| 80 | spin_unlock_irqrestore(&iot->lock, flags); |
| 81 | } |
| 82 | |
| 83 | static void __iot_io_end(struct io_tracker *iot, sector_t len) |
| 84 | { |
| 85 | iot->in_flight -= len; |
| 86 | if (!iot->in_flight) |
| 87 | iot->idle_time = jiffies; |
| 88 | } |
| 89 | |
| 90 | static void iot_io_end(struct io_tracker *iot, sector_t len) |
| 91 | { |
| 92 | unsigned long flags; |
| 93 | |
| 94 | spin_lock_irqsave(&iot->lock, flags); |
| 95 | __iot_io_end(iot, len); |
| 96 | spin_unlock_irqrestore(&iot->lock, flags); |
| 97 | } |
| 98 | |
| 99 | /*----------------------------------------------------------------*/ |
| 100 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 101 | /* |
| 102 | * Glossary: |
| 103 | * |
| 104 | * oblock: index of an origin block |
| 105 | * cblock: index of a cache block |
| 106 | * promotion: movement of a block from origin to cache |
| 107 | * demotion: movement of a block from cache to origin |
| 108 | * migration: movement of a block between the origin and cache device, |
| 109 | * either direction |
| 110 | */ |
| 111 | |
| 112 | /*----------------------------------------------------------------*/ |
| 113 | |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 114 | /* |
| 115 | * There are a couple of places where we let a bio run, but want to do some |
| 116 | * work before calling its endio function. We do this by temporarily |
| 117 | * changing the endio fn. |
| 118 | */ |
| 119 | struct dm_hook_info { |
| 120 | bio_end_io_t *bi_end_io; |
| 121 | void *bi_private; |
| 122 | }; |
| 123 | |
| 124 | static void dm_hook_bio(struct dm_hook_info *h, struct bio *bio, |
| 125 | bio_end_io_t *bi_end_io, void *bi_private) |
| 126 | { |
| 127 | h->bi_end_io = bio->bi_end_io; |
| 128 | h->bi_private = bio->bi_private; |
| 129 | |
| 130 | bio->bi_end_io = bi_end_io; |
| 131 | bio->bi_private = bi_private; |
| 132 | } |
| 133 | |
| 134 | static void dm_unhook_bio(struct dm_hook_info *h, struct bio *bio) |
| 135 | { |
| 136 | bio->bi_end_io = h->bi_end_io; |
| 137 | bio->bi_private = h->bi_private; |
| 138 | } |
| 139 | |
| 140 | /*----------------------------------------------------------------*/ |
| 141 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 142 | #define MIGRATION_POOL_SIZE 128 |
| 143 | #define COMMIT_PERIOD HZ |
| 144 | #define MIGRATION_COUNT_WINDOW 10 |
| 145 | |
| 146 | /* |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 147 | * The block size of the device holding cache data must be |
| 148 | * between 32KB and 1GB. |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 149 | */ |
| 150 | #define DATA_DEV_BLOCK_SIZE_MIN_SECTORS (32 * 1024 >> SECTOR_SHIFT) |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 151 | #define DATA_DEV_BLOCK_SIZE_MAX_SECTORS (1024 * 1024 * 1024 >> SECTOR_SHIFT) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 152 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 153 | enum cache_metadata_mode { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 154 | CM_WRITE, /* metadata may be changed */ |
| 155 | CM_READ_ONLY, /* metadata may not be changed */ |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 156 | CM_FAIL |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 157 | }; |
| 158 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 159 | enum cache_io_mode { |
| 160 | /* |
| 161 | * Data is written to cached blocks only. These blocks are marked |
| 162 | * dirty. If you lose the cache device you will lose data. |
| 163 | * Potential performance increase for both reads and writes. |
| 164 | */ |
| 165 | CM_IO_WRITEBACK, |
| 166 | |
| 167 | /* |
| 168 | * Data is written to both cache and origin. Blocks are never |
| 169 | * dirty. Potential performance benfit for reads only. |
| 170 | */ |
| 171 | CM_IO_WRITETHROUGH, |
| 172 | |
| 173 | /* |
| 174 | * A degraded mode useful for various cache coherency situations |
| 175 | * (eg, rolling back snapshots). Reads and writes always go to the |
| 176 | * origin. If a write goes to a cached oblock, then the cache |
| 177 | * block is invalidated. |
| 178 | */ |
| 179 | CM_IO_PASSTHROUGH |
| 180 | }; |
| 181 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 182 | struct cache_features { |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 183 | enum cache_metadata_mode mode; |
| 184 | enum cache_io_mode io_mode; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 185 | }; |
| 186 | |
| 187 | struct cache_stats { |
| 188 | atomic_t read_hit; |
| 189 | atomic_t read_miss; |
| 190 | atomic_t write_hit; |
| 191 | atomic_t write_miss; |
| 192 | atomic_t demotion; |
| 193 | atomic_t promotion; |
| 194 | atomic_t copies_avoided; |
| 195 | atomic_t cache_cell_clash; |
| 196 | atomic_t commit_count; |
| 197 | atomic_t discard_count; |
| 198 | }; |
| 199 | |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 200 | /* |
| 201 | * Defines a range of cblocks, begin to (end - 1) are in the range. end is |
| 202 | * the one-past-the-end value. |
| 203 | */ |
| 204 | struct cblock_range { |
| 205 | dm_cblock_t begin; |
| 206 | dm_cblock_t end; |
| 207 | }; |
| 208 | |
| 209 | struct invalidation_request { |
| 210 | struct list_head list; |
| 211 | struct cblock_range *cblocks; |
| 212 | |
| 213 | atomic_t complete; |
| 214 | int err; |
| 215 | |
| 216 | wait_queue_head_t result_wait; |
| 217 | }; |
| 218 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 219 | struct cache { |
| 220 | struct dm_target *ti; |
| 221 | struct dm_target_callbacks callbacks; |
| 222 | |
Mike Snitzer | c9ec5d7 | 2013-08-16 10:54:21 -0400 | [diff] [blame] | 223 | struct dm_cache_metadata *cmd; |
| 224 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 225 | /* |
| 226 | * Metadata is written to this device. |
| 227 | */ |
| 228 | struct dm_dev *metadata_dev; |
| 229 | |
| 230 | /* |
| 231 | * The slower of the two data devices. Typically a spindle. |
| 232 | */ |
| 233 | struct dm_dev *origin_dev; |
| 234 | |
| 235 | /* |
| 236 | * The faster of the two data devices. Typically an SSD. |
| 237 | */ |
| 238 | struct dm_dev *cache_dev; |
| 239 | |
| 240 | /* |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 241 | * Size of the origin device in _complete_ blocks and native sectors. |
| 242 | */ |
| 243 | dm_oblock_t origin_blocks; |
| 244 | sector_t origin_sectors; |
| 245 | |
| 246 | /* |
| 247 | * Size of the cache device in blocks. |
| 248 | */ |
| 249 | dm_cblock_t cache_size; |
| 250 | |
| 251 | /* |
| 252 | * Fields for converting from sectors to blocks. |
| 253 | */ |
| 254 | uint32_t sectors_per_block; |
| 255 | int sectors_per_block_shift; |
| 256 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 257 | spinlock_t lock; |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 258 | struct list_head deferred_cells; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 259 | struct bio_list deferred_bios; |
| 260 | struct bio_list deferred_flush_bios; |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 261 | struct bio_list deferred_writethrough_bios; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 262 | struct list_head quiesced_migrations; |
| 263 | struct list_head completed_migrations; |
| 264 | struct list_head need_commit_migrations; |
| 265 | sector_t migration_threshold; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 266 | wait_queue_head_t migration_wait; |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 267 | atomic_t nr_allocated_migrations; |
| 268 | |
| 269 | /* |
| 270 | * The number of in flight migrations that are performing |
| 271 | * background io. eg, promotion, writeback. |
| 272 | */ |
| 273 | atomic_t nr_io_migrations; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 274 | |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 275 | wait_queue_head_t quiescing_wait; |
Joe Thornber | 238f836 | 2013-10-30 17:29:30 +0000 | [diff] [blame] | 276 | atomic_t quiescing; |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 277 | atomic_t quiescing_ack; |
| 278 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 279 | /* |
| 280 | * cache_size entries, dirty if set |
| 281 | */ |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 282 | atomic_t nr_dirty; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 283 | unsigned long *dirty_bitset; |
| 284 | |
| 285 | /* |
| 286 | * origin_blocks entries, discarded if set. |
| 287 | */ |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 288 | dm_dblock_t discard_nr_blocks; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 289 | unsigned long *discard_bitset; |
Joe Thornber | 08b1845 | 2014-11-06 14:38:01 +0000 | [diff] [blame] | 290 | uint32_t discard_block_size; /* a power of 2 times sectors per block */ |
Mike Snitzer | c9ec5d7 | 2013-08-16 10:54:21 -0400 | [diff] [blame] | 291 | |
| 292 | /* |
| 293 | * Rather than reconstructing the table line for the status we just |
| 294 | * save it and regurgitate. |
| 295 | */ |
| 296 | unsigned nr_ctr_args; |
| 297 | const char **ctr_args; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 298 | |
| 299 | struct dm_kcopyd_client *copier; |
| 300 | struct workqueue_struct *wq; |
| 301 | struct work_struct worker; |
| 302 | |
| 303 | struct delayed_work waker; |
| 304 | unsigned long last_commit_jiffies; |
| 305 | |
| 306 | struct dm_bio_prison *prison; |
| 307 | struct dm_deferred_set *all_io_ds; |
| 308 | |
| 309 | mempool_t *migration_pool; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 310 | |
| 311 | struct dm_cache_policy *policy; |
| 312 | unsigned policy_nr_args; |
| 313 | |
| 314 | bool need_tick_bio:1; |
| 315 | bool sized:1; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 316 | bool invalidate:1; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 317 | bool commit_requested:1; |
| 318 | bool loaded_mappings:1; |
| 319 | bool loaded_discards:1; |
| 320 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 321 | /* |
Mike Snitzer | c9ec5d7 | 2013-08-16 10:54:21 -0400 | [diff] [blame] | 322 | * Cache features such as write-through. |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 323 | */ |
Mike Snitzer | c9ec5d7 | 2013-08-16 10:54:21 -0400 | [diff] [blame] | 324 | struct cache_features features; |
| 325 | |
| 326 | struct cache_stats stats; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 327 | |
| 328 | /* |
| 329 | * Invalidation fields. |
| 330 | */ |
| 331 | spinlock_t invalidation_lock; |
| 332 | struct list_head invalidation_requests; |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 333 | |
| 334 | struct io_tracker origin_tracker; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 335 | }; |
| 336 | |
| 337 | struct per_bio_data { |
| 338 | bool tick:1; |
| 339 | unsigned req_nr:2; |
| 340 | struct dm_deferred_entry *all_io_entry; |
Mike Snitzer | c6eda5e | 2014-01-31 14:11:54 -0500 | [diff] [blame] | 341 | struct dm_hook_info hook_info; |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 342 | sector_t len; |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 343 | |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 344 | /* |
| 345 | * writethrough fields. These MUST remain at the end of this |
| 346 | * structure and the 'cache' member must be the first as it |
Joe Thornber | aeed142 | 2013-05-10 14:37:18 +0100 | [diff] [blame] | 347 | * is used to determine the offset of the writethrough fields. |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 348 | */ |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 349 | struct cache *cache; |
| 350 | dm_cblock_t cblock; |
Darrick J. Wong | b844fe6 | 2013-04-05 15:36:32 +0100 | [diff] [blame] | 351 | struct dm_bio_details bio_details; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 352 | }; |
| 353 | |
| 354 | struct dm_cache_migration { |
| 355 | struct list_head list; |
| 356 | struct cache *cache; |
| 357 | |
| 358 | unsigned long start_jiffies; |
| 359 | dm_oblock_t old_oblock; |
| 360 | dm_oblock_t new_oblock; |
| 361 | dm_cblock_t cblock; |
| 362 | |
| 363 | bool err:1; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 364 | bool discard:1; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 365 | bool writeback:1; |
| 366 | bool demote:1; |
| 367 | bool promote:1; |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 368 | bool requeue_holder:1; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 369 | bool invalidate:1; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 370 | |
| 371 | struct dm_bio_prison_cell *old_ocell; |
| 372 | struct dm_bio_prison_cell *new_ocell; |
| 373 | }; |
| 374 | |
| 375 | /* |
| 376 | * Processing a bio in the worker thread may require these memory |
| 377 | * allocations. We prealloc to avoid deadlocks (the same worker thread |
| 378 | * frees them back to the mempool). |
| 379 | */ |
| 380 | struct prealloc { |
| 381 | struct dm_cache_migration *mg; |
| 382 | struct dm_bio_prison_cell *cell1; |
| 383 | struct dm_bio_prison_cell *cell2; |
| 384 | }; |
| 385 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 386 | static enum cache_metadata_mode get_cache_mode(struct cache *cache); |
| 387 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 388 | static void wake_worker(struct cache *cache) |
| 389 | { |
| 390 | queue_work(cache->wq, &cache->worker); |
| 391 | } |
| 392 | |
| 393 | /*----------------------------------------------------------------*/ |
| 394 | |
| 395 | static struct dm_bio_prison_cell *alloc_prison_cell(struct cache *cache) |
| 396 | { |
| 397 | /* FIXME: change to use a local slab. */ |
| 398 | return dm_bio_prison_alloc_cell(cache->prison, GFP_NOWAIT); |
| 399 | } |
| 400 | |
| 401 | static void free_prison_cell(struct cache *cache, struct dm_bio_prison_cell *cell) |
| 402 | { |
| 403 | dm_bio_prison_free_cell(cache->prison, cell); |
| 404 | } |
| 405 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 406 | static struct dm_cache_migration *alloc_migration(struct cache *cache) |
| 407 | { |
| 408 | struct dm_cache_migration *mg; |
| 409 | |
| 410 | mg = mempool_alloc(cache->migration_pool, GFP_NOWAIT); |
| 411 | if (mg) { |
| 412 | mg->cache = cache; |
| 413 | atomic_inc(&mg->cache->nr_allocated_migrations); |
| 414 | } |
| 415 | |
| 416 | return mg; |
| 417 | } |
| 418 | |
| 419 | static void free_migration(struct dm_cache_migration *mg) |
| 420 | { |
Joe Thornber | 88bf5184 | 2015-05-27 15:39:45 +0100 | [diff] [blame] | 421 | struct cache *cache = mg->cache; |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 422 | |
Joe Thornber | 88bf5184 | 2015-05-27 15:39:45 +0100 | [diff] [blame] | 423 | if (atomic_dec_and_test(&cache->nr_allocated_migrations)) |
| 424 | wake_up(&cache->migration_wait); |
| 425 | |
| 426 | mempool_free(mg, cache->migration_pool); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 427 | } |
| 428 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 429 | static int prealloc_data_structs(struct cache *cache, struct prealloc *p) |
| 430 | { |
| 431 | if (!p->mg) { |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 432 | p->mg = alloc_migration(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 433 | if (!p->mg) |
| 434 | return -ENOMEM; |
| 435 | } |
| 436 | |
| 437 | if (!p->cell1) { |
| 438 | p->cell1 = alloc_prison_cell(cache); |
| 439 | if (!p->cell1) |
| 440 | return -ENOMEM; |
| 441 | } |
| 442 | |
| 443 | if (!p->cell2) { |
| 444 | p->cell2 = alloc_prison_cell(cache); |
| 445 | if (!p->cell2) |
| 446 | return -ENOMEM; |
| 447 | } |
| 448 | |
| 449 | return 0; |
| 450 | } |
| 451 | |
| 452 | static void prealloc_free_structs(struct cache *cache, struct prealloc *p) |
| 453 | { |
| 454 | if (p->cell2) |
| 455 | free_prison_cell(cache, p->cell2); |
| 456 | |
| 457 | if (p->cell1) |
| 458 | free_prison_cell(cache, p->cell1); |
| 459 | |
| 460 | if (p->mg) |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 461 | free_migration(p->mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 462 | } |
| 463 | |
| 464 | static struct dm_cache_migration *prealloc_get_migration(struct prealloc *p) |
| 465 | { |
| 466 | struct dm_cache_migration *mg = p->mg; |
| 467 | |
| 468 | BUG_ON(!mg); |
| 469 | p->mg = NULL; |
| 470 | |
| 471 | return mg; |
| 472 | } |
| 473 | |
| 474 | /* |
| 475 | * You must have a cell within the prealloc struct to return. If not this |
| 476 | * function will BUG() rather than returning NULL. |
| 477 | */ |
| 478 | static struct dm_bio_prison_cell *prealloc_get_cell(struct prealloc *p) |
| 479 | { |
| 480 | struct dm_bio_prison_cell *r = NULL; |
| 481 | |
| 482 | if (p->cell1) { |
| 483 | r = p->cell1; |
| 484 | p->cell1 = NULL; |
| 485 | |
| 486 | } else if (p->cell2) { |
| 487 | r = p->cell2; |
| 488 | p->cell2 = NULL; |
| 489 | } else |
| 490 | BUG(); |
| 491 | |
| 492 | return r; |
| 493 | } |
| 494 | |
| 495 | /* |
| 496 | * You can't have more than two cells in a prealloc struct. BUG() will be |
| 497 | * called if you try and overfill. |
| 498 | */ |
| 499 | static void prealloc_put_cell(struct prealloc *p, struct dm_bio_prison_cell *cell) |
| 500 | { |
| 501 | if (!p->cell2) |
| 502 | p->cell2 = cell; |
| 503 | |
| 504 | else if (!p->cell1) |
| 505 | p->cell1 = cell; |
| 506 | |
| 507 | else |
| 508 | BUG(); |
| 509 | } |
| 510 | |
| 511 | /*----------------------------------------------------------------*/ |
| 512 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 513 | static void build_key(dm_oblock_t begin, dm_oblock_t end, struct dm_cell_key *key) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 514 | { |
| 515 | key->virtual = 0; |
| 516 | key->dev = 0; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 517 | key->block_begin = from_oblock(begin); |
| 518 | key->block_end = from_oblock(end); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 519 | } |
| 520 | |
| 521 | /* |
| 522 | * The caller hands in a preallocated cell, and a free function for it. |
| 523 | * The cell will be freed if there's an error, or if it wasn't used because |
| 524 | * a cell with that key already exists. |
| 525 | */ |
| 526 | typedef void (*cell_free_fn)(void *context, struct dm_bio_prison_cell *cell); |
| 527 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 528 | static int bio_detain_range(struct cache *cache, dm_oblock_t oblock_begin, dm_oblock_t oblock_end, |
| 529 | struct bio *bio, struct dm_bio_prison_cell *cell_prealloc, |
| 530 | cell_free_fn free_fn, void *free_context, |
| 531 | struct dm_bio_prison_cell **cell_result) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 532 | { |
| 533 | int r; |
| 534 | struct dm_cell_key key; |
| 535 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 536 | build_key(oblock_begin, oblock_end, &key); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 537 | r = dm_bio_detain(cache->prison, &key, bio, cell_prealloc, cell_result); |
| 538 | if (r) |
| 539 | free_fn(free_context, cell_prealloc); |
| 540 | |
| 541 | return r; |
| 542 | } |
| 543 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 544 | static int bio_detain(struct cache *cache, dm_oblock_t oblock, |
| 545 | struct bio *bio, struct dm_bio_prison_cell *cell_prealloc, |
| 546 | cell_free_fn free_fn, void *free_context, |
| 547 | struct dm_bio_prison_cell **cell_result) |
| 548 | { |
| 549 | dm_oblock_t end = to_oblock(from_oblock(oblock) + 1ULL); |
| 550 | return bio_detain_range(cache, oblock, end, bio, |
| 551 | cell_prealloc, free_fn, free_context, cell_result); |
| 552 | } |
| 553 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 554 | static int get_cell(struct cache *cache, |
| 555 | dm_oblock_t oblock, |
| 556 | struct prealloc *structs, |
| 557 | struct dm_bio_prison_cell **cell_result) |
| 558 | { |
| 559 | int r; |
| 560 | struct dm_cell_key key; |
| 561 | struct dm_bio_prison_cell *cell_prealloc; |
| 562 | |
| 563 | cell_prealloc = prealloc_get_cell(structs); |
| 564 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 565 | build_key(oblock, to_oblock(from_oblock(oblock) + 1ULL), &key); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 566 | r = dm_get_cell(cache->prison, &key, cell_prealloc, cell_result); |
| 567 | if (r) |
| 568 | prealloc_put_cell(structs, cell_prealloc); |
| 569 | |
| 570 | return r; |
| 571 | } |
| 572 | |
Joe Thornber | aeed142 | 2013-05-10 14:37:18 +0100 | [diff] [blame] | 573 | /*----------------------------------------------------------------*/ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 574 | |
| 575 | static bool is_dirty(struct cache *cache, dm_cblock_t b) |
| 576 | { |
| 577 | return test_bit(from_cblock(b), cache->dirty_bitset); |
| 578 | } |
| 579 | |
| 580 | static void set_dirty(struct cache *cache, dm_oblock_t oblock, dm_cblock_t cblock) |
| 581 | { |
| 582 | if (!test_and_set_bit(from_cblock(cblock), cache->dirty_bitset)) { |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 583 | atomic_inc(&cache->nr_dirty); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 584 | policy_set_dirty(cache->policy, oblock); |
| 585 | } |
| 586 | } |
| 587 | |
| 588 | static void clear_dirty(struct cache *cache, dm_oblock_t oblock, dm_cblock_t cblock) |
| 589 | { |
| 590 | if (test_and_clear_bit(from_cblock(cblock), cache->dirty_bitset)) { |
| 591 | policy_clear_dirty(cache->policy, oblock); |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 592 | if (atomic_dec_return(&cache->nr_dirty) == 0) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 593 | dm_table_event(cache->ti->table); |
| 594 | } |
| 595 | } |
| 596 | |
| 597 | /*----------------------------------------------------------------*/ |
Joe Thornber | aeed142 | 2013-05-10 14:37:18 +0100 | [diff] [blame] | 598 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 599 | static bool block_size_is_power_of_two(struct cache *cache) |
| 600 | { |
| 601 | return cache->sectors_per_block_shift >= 0; |
| 602 | } |
| 603 | |
Mikulas Patocka | 43aeaa2 | 2013-07-10 23:41:17 +0100 | [diff] [blame] | 604 | /* gcc on ARM generates spurious references to __udivdi3 and __umoddi3 */ |
| 605 | #if defined(CONFIG_ARM) && __GNUC__ == 4 && __GNUC_MINOR__ <= 6 |
| 606 | __always_inline |
| 607 | #endif |
Joe Thornber | 414dd67 | 2013-03-20 17:21:25 +0000 | [diff] [blame] | 608 | static dm_block_t block_div(dm_block_t b, uint32_t n) |
| 609 | { |
| 610 | do_div(b, n); |
| 611 | |
| 612 | return b; |
| 613 | } |
| 614 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 615 | static dm_block_t oblocks_per_dblock(struct cache *cache) |
| 616 | { |
| 617 | dm_block_t oblocks = cache->discard_block_size; |
| 618 | |
| 619 | if (block_size_is_power_of_two(cache)) |
| 620 | oblocks >>= cache->sectors_per_block_shift; |
| 621 | else |
| 622 | oblocks = block_div(oblocks, cache->sectors_per_block); |
| 623 | |
| 624 | return oblocks; |
| 625 | } |
| 626 | |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 627 | static dm_dblock_t oblock_to_dblock(struct cache *cache, dm_oblock_t oblock) |
| 628 | { |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 629 | return to_dblock(block_div(from_oblock(oblock), |
| 630 | oblocks_per_dblock(cache))); |
| 631 | } |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 632 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 633 | static dm_oblock_t dblock_to_oblock(struct cache *cache, dm_dblock_t dblock) |
| 634 | { |
| 635 | return to_oblock(from_dblock(dblock) * oblocks_per_dblock(cache)); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 636 | } |
| 637 | |
| 638 | static void set_discard(struct cache *cache, dm_dblock_t b) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 639 | { |
| 640 | unsigned long flags; |
| 641 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 642 | BUG_ON(from_dblock(b) >= from_dblock(cache->discard_nr_blocks)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 643 | atomic_inc(&cache->stats.discard_count); |
| 644 | |
| 645 | spin_lock_irqsave(&cache->lock, flags); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 646 | set_bit(from_dblock(b), cache->discard_bitset); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 647 | spin_unlock_irqrestore(&cache->lock, flags); |
| 648 | } |
| 649 | |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 650 | static void clear_discard(struct cache *cache, dm_dblock_t b) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 651 | { |
| 652 | unsigned long flags; |
| 653 | |
| 654 | spin_lock_irqsave(&cache->lock, flags); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 655 | clear_bit(from_dblock(b), cache->discard_bitset); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 656 | spin_unlock_irqrestore(&cache->lock, flags); |
| 657 | } |
| 658 | |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 659 | static bool is_discarded(struct cache *cache, dm_dblock_t b) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 660 | { |
| 661 | int r; |
| 662 | unsigned long flags; |
| 663 | |
| 664 | spin_lock_irqsave(&cache->lock, flags); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 665 | r = test_bit(from_dblock(b), cache->discard_bitset); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 666 | spin_unlock_irqrestore(&cache->lock, flags); |
| 667 | |
| 668 | return r; |
| 669 | } |
| 670 | |
| 671 | static bool is_discarded_oblock(struct cache *cache, dm_oblock_t b) |
| 672 | { |
| 673 | int r; |
| 674 | unsigned long flags; |
| 675 | |
| 676 | spin_lock_irqsave(&cache->lock, flags); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 677 | r = test_bit(from_dblock(oblock_to_dblock(cache, b)), |
| 678 | cache->discard_bitset); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 679 | spin_unlock_irqrestore(&cache->lock, flags); |
| 680 | |
| 681 | return r; |
| 682 | } |
| 683 | |
| 684 | /*----------------------------------------------------------------*/ |
| 685 | |
| 686 | static void load_stats(struct cache *cache) |
| 687 | { |
| 688 | struct dm_cache_statistics stats; |
| 689 | |
| 690 | dm_cache_metadata_get_stats(cache->cmd, &stats); |
| 691 | atomic_set(&cache->stats.read_hit, stats.read_hits); |
| 692 | atomic_set(&cache->stats.read_miss, stats.read_misses); |
| 693 | atomic_set(&cache->stats.write_hit, stats.write_hits); |
| 694 | atomic_set(&cache->stats.write_miss, stats.write_misses); |
| 695 | } |
| 696 | |
| 697 | static void save_stats(struct cache *cache) |
| 698 | { |
| 699 | struct dm_cache_statistics stats; |
| 700 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 701 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 702 | return; |
| 703 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 704 | stats.read_hits = atomic_read(&cache->stats.read_hit); |
| 705 | stats.read_misses = atomic_read(&cache->stats.read_miss); |
| 706 | stats.write_hits = atomic_read(&cache->stats.write_hit); |
| 707 | stats.write_misses = atomic_read(&cache->stats.write_miss); |
| 708 | |
| 709 | dm_cache_metadata_set_stats(cache->cmd, &stats); |
| 710 | } |
| 711 | |
| 712 | /*---------------------------------------------------------------- |
| 713 | * Per bio data |
| 714 | *--------------------------------------------------------------*/ |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 715 | |
| 716 | /* |
| 717 | * If using writeback, leave out struct per_bio_data's writethrough fields. |
| 718 | */ |
| 719 | #define PB_DATA_SIZE_WB (offsetof(struct per_bio_data, cache)) |
| 720 | #define PB_DATA_SIZE_WT (sizeof(struct per_bio_data)) |
| 721 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 722 | static bool writethrough_mode(struct cache_features *f) |
| 723 | { |
| 724 | return f->io_mode == CM_IO_WRITETHROUGH; |
| 725 | } |
| 726 | |
| 727 | static bool writeback_mode(struct cache_features *f) |
| 728 | { |
| 729 | return f->io_mode == CM_IO_WRITEBACK; |
| 730 | } |
| 731 | |
| 732 | static bool passthrough_mode(struct cache_features *f) |
| 733 | { |
| 734 | return f->io_mode == CM_IO_PASSTHROUGH; |
| 735 | } |
| 736 | |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 737 | static size_t get_per_bio_data_size(struct cache *cache) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 738 | { |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 739 | return writethrough_mode(&cache->features) ? PB_DATA_SIZE_WT : PB_DATA_SIZE_WB; |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 740 | } |
| 741 | |
| 742 | static struct per_bio_data *get_per_bio_data(struct bio *bio, size_t data_size) |
| 743 | { |
| 744 | struct per_bio_data *pb = dm_per_bio_data(bio, data_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 745 | BUG_ON(!pb); |
| 746 | return pb; |
| 747 | } |
| 748 | |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 749 | static struct per_bio_data *init_per_bio_data(struct bio *bio, size_t data_size) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 750 | { |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 751 | struct per_bio_data *pb = get_per_bio_data(bio, data_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 752 | |
| 753 | pb->tick = false; |
| 754 | pb->req_nr = dm_bio_get_target_bio_nr(bio); |
| 755 | pb->all_io_entry = NULL; |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 756 | pb->len = 0; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 757 | |
| 758 | return pb; |
| 759 | } |
| 760 | |
| 761 | /*---------------------------------------------------------------- |
| 762 | * Remapping |
| 763 | *--------------------------------------------------------------*/ |
| 764 | static void remap_to_origin(struct cache *cache, struct bio *bio) |
| 765 | { |
| 766 | bio->bi_bdev = cache->origin_dev->bdev; |
| 767 | } |
| 768 | |
| 769 | static void remap_to_cache(struct cache *cache, struct bio *bio, |
| 770 | dm_cblock_t cblock) |
| 771 | { |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 772 | sector_t bi_sector = bio->bi_iter.bi_sector; |
Heinz Mauelshagen | e0d849f | 2014-02-27 22:46:48 +0100 | [diff] [blame] | 773 | sector_t block = from_cblock(cblock); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 774 | |
| 775 | bio->bi_bdev = cache->cache_dev->bdev; |
| 776 | if (!block_size_is_power_of_two(cache)) |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 777 | bio->bi_iter.bi_sector = |
Heinz Mauelshagen | e0d849f | 2014-02-27 22:46:48 +0100 | [diff] [blame] | 778 | (block * cache->sectors_per_block) + |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 779 | sector_div(bi_sector, cache->sectors_per_block); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 780 | else |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 781 | bio->bi_iter.bi_sector = |
Heinz Mauelshagen | e0d849f | 2014-02-27 22:46:48 +0100 | [diff] [blame] | 782 | (block << cache->sectors_per_block_shift) | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 783 | (bi_sector & (cache->sectors_per_block - 1)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 784 | } |
| 785 | |
| 786 | static void check_if_tick_bio_needed(struct cache *cache, struct bio *bio) |
| 787 | { |
| 788 | unsigned long flags; |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 789 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 790 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 791 | |
| 792 | spin_lock_irqsave(&cache->lock, flags); |
| 793 | if (cache->need_tick_bio && |
| 794 | !(bio->bi_rw & (REQ_FUA | REQ_FLUSH | REQ_DISCARD))) { |
| 795 | pb->tick = true; |
| 796 | cache->need_tick_bio = false; |
| 797 | } |
| 798 | spin_unlock_irqrestore(&cache->lock, flags); |
| 799 | } |
| 800 | |
| 801 | static void remap_to_origin_clear_discard(struct cache *cache, struct bio *bio, |
| 802 | dm_oblock_t oblock) |
| 803 | { |
| 804 | check_if_tick_bio_needed(cache, bio); |
| 805 | remap_to_origin(cache, bio); |
| 806 | if (bio_data_dir(bio) == WRITE) |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 807 | clear_discard(cache, oblock_to_dblock(cache, oblock)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 808 | } |
| 809 | |
| 810 | static void remap_to_cache_dirty(struct cache *cache, struct bio *bio, |
| 811 | dm_oblock_t oblock, dm_cblock_t cblock) |
| 812 | { |
Joe Thornber | f8e5f01 | 2013-10-21 12:51:45 +0100 | [diff] [blame] | 813 | check_if_tick_bio_needed(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 814 | remap_to_cache(cache, bio, cblock); |
| 815 | if (bio_data_dir(bio) == WRITE) { |
| 816 | set_dirty(cache, oblock, cblock); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 817 | clear_discard(cache, oblock_to_dblock(cache, oblock)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 818 | } |
| 819 | } |
| 820 | |
| 821 | static dm_oblock_t get_bio_block(struct cache *cache, struct bio *bio) |
| 822 | { |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 823 | sector_t block_nr = bio->bi_iter.bi_sector; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 824 | |
| 825 | if (!block_size_is_power_of_two(cache)) |
| 826 | (void) sector_div(block_nr, cache->sectors_per_block); |
| 827 | else |
| 828 | block_nr >>= cache->sectors_per_block_shift; |
| 829 | |
| 830 | return to_oblock(block_nr); |
| 831 | } |
| 832 | |
| 833 | static int bio_triggers_commit(struct cache *cache, struct bio *bio) |
| 834 | { |
| 835 | return bio->bi_rw & (REQ_FLUSH | REQ_FUA); |
| 836 | } |
| 837 | |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 838 | /* |
| 839 | * You must increment the deferred set whilst the prison cell is held. To |
| 840 | * encourage this, we ask for 'cell' to be passed in. |
| 841 | */ |
| 842 | static void inc_ds(struct cache *cache, struct bio *bio, |
| 843 | struct dm_bio_prison_cell *cell) |
| 844 | { |
| 845 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 846 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
| 847 | |
| 848 | BUG_ON(!cell); |
| 849 | BUG_ON(pb->all_io_entry); |
| 850 | |
| 851 | pb->all_io_entry = dm_deferred_entry_inc(cache->all_io_ds); |
| 852 | } |
| 853 | |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 854 | static bool accountable_bio(struct cache *cache, struct bio *bio) |
| 855 | { |
| 856 | return ((bio->bi_bdev == cache->origin_dev->bdev) && |
| 857 | !(bio->bi_rw & REQ_DISCARD)); |
| 858 | } |
| 859 | |
| 860 | static void accounted_begin(struct cache *cache, struct bio *bio) |
| 861 | { |
| 862 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 863 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
| 864 | |
| 865 | if (accountable_bio(cache, bio)) { |
| 866 | pb->len = bio_sectors(bio); |
| 867 | iot_io_begin(&cache->origin_tracker, pb->len); |
| 868 | } |
| 869 | } |
| 870 | |
| 871 | static void accounted_complete(struct cache *cache, struct bio *bio) |
| 872 | { |
| 873 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 874 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
| 875 | |
| 876 | iot_io_end(&cache->origin_tracker, pb->len); |
| 877 | } |
| 878 | |
| 879 | static void accounted_request(struct cache *cache, struct bio *bio) |
| 880 | { |
| 881 | accounted_begin(cache, bio); |
| 882 | generic_make_request(bio); |
| 883 | } |
| 884 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 885 | static void issue(struct cache *cache, struct bio *bio) |
| 886 | { |
| 887 | unsigned long flags; |
| 888 | |
| 889 | if (!bio_triggers_commit(cache, bio)) { |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 890 | accounted_request(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 891 | return; |
| 892 | } |
| 893 | |
| 894 | /* |
| 895 | * Batch together any bios that trigger commits and then issue a |
| 896 | * single commit for them in do_worker(). |
| 897 | */ |
| 898 | spin_lock_irqsave(&cache->lock, flags); |
| 899 | cache->commit_requested = true; |
| 900 | bio_list_add(&cache->deferred_flush_bios, bio); |
| 901 | spin_unlock_irqrestore(&cache->lock, flags); |
| 902 | } |
| 903 | |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 904 | static void inc_and_issue(struct cache *cache, struct bio *bio, struct dm_bio_prison_cell *cell) |
| 905 | { |
| 906 | inc_ds(cache, bio, cell); |
| 907 | issue(cache, bio); |
| 908 | } |
| 909 | |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 910 | static void defer_writethrough_bio(struct cache *cache, struct bio *bio) |
| 911 | { |
| 912 | unsigned long flags; |
| 913 | |
| 914 | spin_lock_irqsave(&cache->lock, flags); |
| 915 | bio_list_add(&cache->deferred_writethrough_bios, bio); |
| 916 | spin_unlock_irqrestore(&cache->lock, flags); |
| 917 | |
| 918 | wake_worker(cache); |
| 919 | } |
| 920 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 921 | static void writethrough_endio(struct bio *bio) |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 922 | { |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 923 | struct per_bio_data *pb = get_per_bio_data(bio, PB_DATA_SIZE_WT); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 924 | |
| 925 | dm_unhook_bio(&pb->hook_info, bio); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 926 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 927 | if (bio->bi_error) { |
| 928 | bio_endio(bio); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 929 | return; |
| 930 | } |
| 931 | |
Darrick J. Wong | b844fe6 | 2013-04-05 15:36:32 +0100 | [diff] [blame] | 932 | dm_bio_restore(&pb->bio_details, bio); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 933 | remap_to_cache(pb->cache, bio, pb->cblock); |
| 934 | |
| 935 | /* |
| 936 | * We can't issue this bio directly, since we're in interrupt |
Joe Thornber | aeed142 | 2013-05-10 14:37:18 +0100 | [diff] [blame] | 937 | * context. So it gets put on a bio list for processing by the |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 938 | * worker thread. |
| 939 | */ |
| 940 | defer_writethrough_bio(pb->cache, bio); |
| 941 | } |
| 942 | |
| 943 | /* |
| 944 | * When running in writethrough mode we need to send writes to clean blocks |
| 945 | * to both the cache and origin devices. In future we'd like to clone the |
| 946 | * bio and send them in parallel, but for now we're doing them in |
| 947 | * series as this is easier. |
| 948 | */ |
| 949 | static void remap_to_origin_then_cache(struct cache *cache, struct bio *bio, |
| 950 | dm_oblock_t oblock, dm_cblock_t cblock) |
| 951 | { |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 952 | struct per_bio_data *pb = get_per_bio_data(bio, PB_DATA_SIZE_WT); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 953 | |
| 954 | pb->cache = cache; |
| 955 | pb->cblock = cblock; |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 956 | dm_hook_bio(&pb->hook_info, bio, writethrough_endio, NULL); |
Darrick J. Wong | b844fe6 | 2013-04-05 15:36:32 +0100 | [diff] [blame] | 957 | dm_bio_record(&pb->bio_details, bio); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 958 | |
| 959 | remap_to_origin_clear_discard(pb->cache, bio, oblock); |
| 960 | } |
| 961 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 962 | /*---------------------------------------------------------------- |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 963 | * Failure modes |
| 964 | *--------------------------------------------------------------*/ |
| 965 | static enum cache_metadata_mode get_cache_mode(struct cache *cache) |
| 966 | { |
| 967 | return cache->features.mode; |
| 968 | } |
| 969 | |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 970 | static const char *cache_device_name(struct cache *cache) |
| 971 | { |
| 972 | return dm_device_name(dm_table_get_md(cache->ti->table)); |
| 973 | } |
| 974 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 975 | static void notify_mode_switch(struct cache *cache, enum cache_metadata_mode mode) |
| 976 | { |
| 977 | const char *descs[] = { |
| 978 | "write", |
| 979 | "read-only", |
| 980 | "fail" |
| 981 | }; |
| 982 | |
| 983 | dm_table_event(cache->ti->table); |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 984 | DMINFO("%s: switching cache to %s mode", |
| 985 | cache_device_name(cache), descs[(int)mode]); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 986 | } |
| 987 | |
| 988 | static void set_cache_mode(struct cache *cache, enum cache_metadata_mode new_mode) |
| 989 | { |
| 990 | bool needs_check = dm_cache_metadata_needs_check(cache->cmd); |
| 991 | enum cache_metadata_mode old_mode = get_cache_mode(cache); |
| 992 | |
| 993 | if (new_mode == CM_WRITE && needs_check) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 994 | DMERR("%s: unable to switch cache to write mode until repaired.", |
| 995 | cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 996 | if (old_mode != new_mode) |
| 997 | new_mode = old_mode; |
| 998 | else |
| 999 | new_mode = CM_READ_ONLY; |
| 1000 | } |
| 1001 | |
| 1002 | /* Never move out of fail mode */ |
| 1003 | if (old_mode == CM_FAIL) |
| 1004 | new_mode = CM_FAIL; |
| 1005 | |
| 1006 | switch (new_mode) { |
| 1007 | case CM_FAIL: |
| 1008 | case CM_READ_ONLY: |
| 1009 | dm_cache_metadata_set_read_only(cache->cmd); |
| 1010 | break; |
| 1011 | |
| 1012 | case CM_WRITE: |
| 1013 | dm_cache_metadata_set_read_write(cache->cmd); |
| 1014 | break; |
| 1015 | } |
| 1016 | |
| 1017 | cache->features.mode = new_mode; |
| 1018 | |
| 1019 | if (new_mode != old_mode) |
| 1020 | notify_mode_switch(cache, new_mode); |
| 1021 | } |
| 1022 | |
| 1023 | static void abort_transaction(struct cache *cache) |
| 1024 | { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1025 | const char *dev_name = cache_device_name(cache); |
| 1026 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1027 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 1028 | return; |
| 1029 | |
| 1030 | if (dm_cache_metadata_set_needs_check(cache->cmd)) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1031 | DMERR("%s: failed to set 'needs_check' flag in metadata", dev_name); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1032 | set_cache_mode(cache, CM_FAIL); |
| 1033 | } |
| 1034 | |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1035 | DMERR_LIMIT("%s: aborting current metadata transaction", dev_name); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1036 | if (dm_cache_metadata_abort(cache->cmd)) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1037 | DMERR("%s: failed to abort metadata transaction", dev_name); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1038 | set_cache_mode(cache, CM_FAIL); |
| 1039 | } |
| 1040 | } |
| 1041 | |
| 1042 | static void metadata_operation_failed(struct cache *cache, const char *op, int r) |
| 1043 | { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1044 | DMERR_LIMIT("%s: metadata operation '%s' failed: error = %d", |
| 1045 | cache_device_name(cache), op, r); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1046 | abort_transaction(cache); |
| 1047 | set_cache_mode(cache, CM_READ_ONLY); |
| 1048 | } |
| 1049 | |
| 1050 | /*---------------------------------------------------------------- |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1051 | * Migration processing |
| 1052 | * |
| 1053 | * Migration covers moving data from the origin device to the cache, or |
| 1054 | * vice versa. |
| 1055 | *--------------------------------------------------------------*/ |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1056 | static void inc_io_migrations(struct cache *cache) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1057 | { |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1058 | atomic_inc(&cache->nr_io_migrations); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1059 | } |
| 1060 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1061 | static void dec_io_migrations(struct cache *cache) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1062 | { |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1063 | atomic_dec(&cache->nr_io_migrations); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1064 | } |
| 1065 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1066 | static bool discard_or_flush(struct bio *bio) |
| 1067 | { |
| 1068 | return bio->bi_rw & (REQ_FLUSH | REQ_FUA | REQ_DISCARD); |
| 1069 | } |
| 1070 | |
| 1071 | static void __cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell) |
| 1072 | { |
Mike Snitzer | dc9cee5 | 2015-08-31 15:41:34 -0400 | [diff] [blame] | 1073 | if (discard_or_flush(cell->holder)) { |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1074 | /* |
Mike Snitzer | dc9cee5 | 2015-08-31 15:41:34 -0400 | [diff] [blame] | 1075 | * We have to handle these bios individually. |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1076 | */ |
Mike Snitzer | dc9cee5 | 2015-08-31 15:41:34 -0400 | [diff] [blame] | 1077 | dm_cell_release(cache->prison, cell, &cache->deferred_bios); |
| 1078 | free_prison_cell(cache, cell); |
| 1079 | } else |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1080 | list_add_tail(&cell->user_list, &cache->deferred_cells); |
| 1081 | } |
| 1082 | |
| 1083 | static void cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell, bool holder) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1084 | { |
| 1085 | unsigned long flags; |
| 1086 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1087 | if (!holder && dm_cell_promote_or_release(cache->prison, cell)) { |
| 1088 | /* |
| 1089 | * There was no prisoner to promote to holder, the |
| 1090 | * cell has been released. |
| 1091 | */ |
| 1092 | free_prison_cell(cache, cell); |
| 1093 | return; |
| 1094 | } |
| 1095 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1096 | spin_lock_irqsave(&cache->lock, flags); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1097 | __cell_defer(cache, cell); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1098 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1099 | |
| 1100 | wake_worker(cache); |
| 1101 | } |
| 1102 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1103 | static void cell_error_with_code(struct cache *cache, struct dm_bio_prison_cell *cell, int err) |
| 1104 | { |
| 1105 | dm_cell_error(cache->prison, cell, err); |
Mike Snitzer | dc9cee5 | 2015-08-31 15:41:34 -0400 | [diff] [blame] | 1106 | free_prison_cell(cache, cell); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1107 | } |
| 1108 | |
| 1109 | static void cell_requeue(struct cache *cache, struct dm_bio_prison_cell *cell) |
| 1110 | { |
| 1111 | cell_error_with_code(cache, cell, DM_ENDIO_REQUEUE); |
| 1112 | } |
| 1113 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1114 | static void free_io_migration(struct dm_cache_migration *mg) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1115 | { |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1116 | struct cache *cache = mg->cache; |
| 1117 | |
| 1118 | dec_io_migrations(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1119 | free_migration(mg); |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1120 | wake_worker(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1121 | } |
| 1122 | |
| 1123 | static void migration_failure(struct dm_cache_migration *mg) |
| 1124 | { |
| 1125 | struct cache *cache = mg->cache; |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1126 | const char *dev_name = cache_device_name(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1127 | |
| 1128 | if (mg->writeback) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1129 | DMERR_LIMIT("%s: writeback failed; couldn't copy block", dev_name); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1130 | set_dirty(cache, mg->old_oblock, mg->cblock); |
| 1131 | cell_defer(cache, mg->old_ocell, false); |
| 1132 | |
| 1133 | } else if (mg->demote) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1134 | DMERR_LIMIT("%s: demotion failed; couldn't copy block", dev_name); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1135 | policy_force_mapping(cache->policy, mg->new_oblock, mg->old_oblock); |
| 1136 | |
Heinz Mauelshagen | 80f659f | 2013-10-14 17:10:47 +0200 | [diff] [blame] | 1137 | cell_defer(cache, mg->old_ocell, mg->promote ? false : true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1138 | if (mg->promote) |
Heinz Mauelshagen | 80f659f | 2013-10-14 17:10:47 +0200 | [diff] [blame] | 1139 | cell_defer(cache, mg->new_ocell, true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1140 | } else { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1141 | DMERR_LIMIT("%s: promotion failed; couldn't copy block", dev_name); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1142 | policy_remove_mapping(cache->policy, mg->new_oblock); |
Heinz Mauelshagen | 80f659f | 2013-10-14 17:10:47 +0200 | [diff] [blame] | 1143 | cell_defer(cache, mg->new_ocell, true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1144 | } |
| 1145 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1146 | free_io_migration(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1147 | } |
| 1148 | |
| 1149 | static void migration_success_pre_commit(struct dm_cache_migration *mg) |
| 1150 | { |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1151 | int r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1152 | unsigned long flags; |
| 1153 | struct cache *cache = mg->cache; |
| 1154 | |
| 1155 | if (mg->writeback) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1156 | clear_dirty(cache, mg->old_oblock, mg->cblock); |
Anssi Hannula | 40aa978 | 2014-09-05 03:11:28 +0300 | [diff] [blame] | 1157 | cell_defer(cache, mg->old_ocell, false); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1158 | free_io_migration(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1159 | return; |
| 1160 | |
| 1161 | } else if (mg->demote) { |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1162 | r = dm_cache_remove_mapping(cache->cmd, mg->cblock); |
| 1163 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1164 | DMERR_LIMIT("%s: demotion failed; couldn't update on disk metadata", |
| 1165 | cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1166 | metadata_operation_failed(cache, "dm_cache_remove_mapping", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1167 | policy_force_mapping(cache->policy, mg->new_oblock, |
| 1168 | mg->old_oblock); |
| 1169 | if (mg->promote) |
| 1170 | cell_defer(cache, mg->new_ocell, true); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1171 | free_io_migration(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1172 | return; |
| 1173 | } |
| 1174 | } else { |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1175 | r = dm_cache_insert_mapping(cache->cmd, mg->cblock, mg->new_oblock); |
| 1176 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1177 | DMERR_LIMIT("%s: promotion failed; couldn't update on disk metadata", |
| 1178 | cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1179 | metadata_operation_failed(cache, "dm_cache_insert_mapping", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1180 | policy_remove_mapping(cache->policy, mg->new_oblock); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1181 | free_io_migration(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1182 | return; |
| 1183 | } |
| 1184 | } |
| 1185 | |
| 1186 | spin_lock_irqsave(&cache->lock, flags); |
| 1187 | list_add_tail(&mg->list, &cache->need_commit_migrations); |
| 1188 | cache->commit_requested = true; |
| 1189 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1190 | } |
| 1191 | |
| 1192 | static void migration_success_post_commit(struct dm_cache_migration *mg) |
| 1193 | { |
| 1194 | unsigned long flags; |
| 1195 | struct cache *cache = mg->cache; |
| 1196 | |
| 1197 | if (mg->writeback) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1198 | DMWARN_LIMIT("%s: writeback unexpectedly triggered commit", |
| 1199 | cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1200 | return; |
| 1201 | |
| 1202 | } else if (mg->demote) { |
Heinz Mauelshagen | 80f659f | 2013-10-14 17:10:47 +0200 | [diff] [blame] | 1203 | cell_defer(cache, mg->old_ocell, mg->promote ? false : true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1204 | |
| 1205 | if (mg->promote) { |
| 1206 | mg->demote = false; |
| 1207 | |
| 1208 | spin_lock_irqsave(&cache->lock, flags); |
| 1209 | list_add_tail(&mg->list, &cache->quiesced_migrations); |
| 1210 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1211 | |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1212 | } else { |
| 1213 | if (mg->invalidate) |
| 1214 | policy_remove_mapping(cache->policy, mg->old_oblock); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1215 | free_io_migration(mg); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1216 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1217 | |
| 1218 | } else { |
Joe Thornber | 1e32134 | 2014-11-27 12:26:46 +0000 | [diff] [blame] | 1219 | if (mg->requeue_holder) { |
| 1220 | clear_dirty(cache, mg->new_oblock, mg->cblock); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1221 | cell_defer(cache, mg->new_ocell, true); |
Joe Thornber | 1e32134 | 2014-11-27 12:26:46 +0000 | [diff] [blame] | 1222 | } else { |
| 1223 | /* |
| 1224 | * The block was promoted via an overwrite, so it's dirty. |
| 1225 | */ |
| 1226 | set_dirty(cache, mg->new_oblock, mg->cblock); |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1227 | bio_endio(mg->new_ocell->holder); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1228 | cell_defer(cache, mg->new_ocell, false); |
| 1229 | } |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1230 | free_io_migration(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1231 | } |
| 1232 | } |
| 1233 | |
| 1234 | static void copy_complete(int read_err, unsigned long write_err, void *context) |
| 1235 | { |
| 1236 | unsigned long flags; |
| 1237 | struct dm_cache_migration *mg = (struct dm_cache_migration *) context; |
| 1238 | struct cache *cache = mg->cache; |
| 1239 | |
| 1240 | if (read_err || write_err) |
| 1241 | mg->err = true; |
| 1242 | |
| 1243 | spin_lock_irqsave(&cache->lock, flags); |
| 1244 | list_add_tail(&mg->list, &cache->completed_migrations); |
| 1245 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1246 | |
| 1247 | wake_worker(cache); |
| 1248 | } |
| 1249 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1250 | static void issue_copy(struct dm_cache_migration *mg) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1251 | { |
| 1252 | int r; |
| 1253 | struct dm_io_region o_region, c_region; |
| 1254 | struct cache *cache = mg->cache; |
Heinz Mauelshagen | 8b9d966 | 2014-03-12 00:40:05 +0100 | [diff] [blame] | 1255 | sector_t cblock = from_cblock(mg->cblock); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1256 | |
| 1257 | o_region.bdev = cache->origin_dev->bdev; |
| 1258 | o_region.count = cache->sectors_per_block; |
| 1259 | |
| 1260 | c_region.bdev = cache->cache_dev->bdev; |
Heinz Mauelshagen | 8b9d966 | 2014-03-12 00:40:05 +0100 | [diff] [blame] | 1261 | c_region.sector = cblock * cache->sectors_per_block; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1262 | c_region.count = cache->sectors_per_block; |
| 1263 | |
| 1264 | if (mg->writeback || mg->demote) { |
| 1265 | /* demote */ |
| 1266 | o_region.sector = from_oblock(mg->old_oblock) * cache->sectors_per_block; |
| 1267 | r = dm_kcopyd_copy(cache->copier, &c_region, 1, &o_region, 0, copy_complete, mg); |
| 1268 | } else { |
| 1269 | /* promote */ |
| 1270 | o_region.sector = from_oblock(mg->new_oblock) * cache->sectors_per_block; |
| 1271 | r = dm_kcopyd_copy(cache->copier, &o_region, 1, &c_region, 0, copy_complete, mg); |
| 1272 | } |
| 1273 | |
Heinz Mauelshagen | 2c2263c | 2013-10-14 17:14:45 +0200 | [diff] [blame] | 1274 | if (r < 0) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1275 | DMERR_LIMIT("%s: issuing migration failed", cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1276 | migration_failure(mg); |
Heinz Mauelshagen | 2c2263c | 2013-10-14 17:14:45 +0200 | [diff] [blame] | 1277 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1278 | } |
| 1279 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1280 | static void overwrite_endio(struct bio *bio) |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1281 | { |
| 1282 | struct dm_cache_migration *mg = bio->bi_private; |
| 1283 | struct cache *cache = mg->cache; |
| 1284 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 1285 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
| 1286 | unsigned long flags; |
| 1287 | |
Mike Snitzer | 80ae49a | 2014-01-31 14:30:37 -0500 | [diff] [blame] | 1288 | dm_unhook_bio(&pb->hook_info, bio); |
| 1289 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1290 | if (bio->bi_error) |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1291 | mg->err = true; |
| 1292 | |
Mike Snitzer | 80ae49a | 2014-01-31 14:30:37 -0500 | [diff] [blame] | 1293 | mg->requeue_holder = false; |
| 1294 | |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1295 | spin_lock_irqsave(&cache->lock, flags); |
| 1296 | list_add_tail(&mg->list, &cache->completed_migrations); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1297 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1298 | |
| 1299 | wake_worker(cache); |
| 1300 | } |
| 1301 | |
| 1302 | static void issue_overwrite(struct dm_cache_migration *mg, struct bio *bio) |
| 1303 | { |
| 1304 | size_t pb_data_size = get_per_bio_data_size(mg->cache); |
| 1305 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
| 1306 | |
| 1307 | dm_hook_bio(&pb->hook_info, bio, overwrite_endio, mg); |
| 1308 | remap_to_cache_dirty(mg->cache, bio, mg->new_oblock, mg->cblock); |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1309 | |
| 1310 | /* |
| 1311 | * No need to inc_ds() here, since the cell will be held for the |
| 1312 | * duration of the io. |
| 1313 | */ |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 1314 | accounted_request(mg->cache, bio); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1315 | } |
| 1316 | |
| 1317 | static bool bio_writes_complete_block(struct cache *cache, struct bio *bio) |
| 1318 | { |
| 1319 | return (bio_data_dir(bio) == WRITE) && |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1320 | (bio->bi_iter.bi_size == (cache->sectors_per_block << SECTOR_SHIFT)); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1321 | } |
| 1322 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1323 | static void avoid_copy(struct dm_cache_migration *mg) |
| 1324 | { |
| 1325 | atomic_inc(&mg->cache->stats.copies_avoided); |
| 1326 | migration_success_pre_commit(mg); |
| 1327 | } |
| 1328 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1329 | static void calc_discard_block_range(struct cache *cache, struct bio *bio, |
| 1330 | dm_dblock_t *b, dm_dblock_t *e) |
| 1331 | { |
| 1332 | sector_t sb = bio->bi_iter.bi_sector; |
| 1333 | sector_t se = bio_end_sector(bio); |
| 1334 | |
| 1335 | *b = to_dblock(dm_sector_div_up(sb, cache->discard_block_size)); |
| 1336 | |
| 1337 | if (se - sb < cache->discard_block_size) |
| 1338 | *e = *b; |
| 1339 | else |
| 1340 | *e = to_dblock(block_div(se, cache->discard_block_size)); |
| 1341 | } |
| 1342 | |
| 1343 | static void issue_discard(struct dm_cache_migration *mg) |
| 1344 | { |
| 1345 | dm_dblock_t b, e; |
| 1346 | struct bio *bio = mg->new_ocell->holder; |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1347 | struct cache *cache = mg->cache; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1348 | |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1349 | calc_discard_block_range(cache, bio, &b, &e); |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1350 | while (b != e) { |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1351 | set_discard(cache, b); |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1352 | b = to_dblock(from_dblock(b) + 1); |
| 1353 | } |
| 1354 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1355 | bio_endio(bio); |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1356 | cell_defer(cache, mg->new_ocell, false); |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1357 | free_migration(mg); |
Joe Thornber | cc7da0b | 2015-09-01 11:38:19 +0100 | [diff] [blame] | 1358 | wake_worker(cache); |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1359 | } |
| 1360 | |
| 1361 | static void issue_copy_or_discard(struct dm_cache_migration *mg) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1362 | { |
| 1363 | bool avoid; |
| 1364 | struct cache *cache = mg->cache; |
| 1365 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1366 | if (mg->discard) { |
| 1367 | issue_discard(mg); |
| 1368 | return; |
| 1369 | } |
| 1370 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1371 | if (mg->writeback || mg->demote) |
| 1372 | avoid = !is_dirty(cache, mg->cblock) || |
| 1373 | is_discarded_oblock(cache, mg->old_oblock); |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1374 | else { |
| 1375 | struct bio *bio = mg->new_ocell->holder; |
| 1376 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1377 | avoid = is_discarded_oblock(cache, mg->new_oblock); |
| 1378 | |
Joe Thornber | f29a314 | 2014-11-27 12:21:08 +0000 | [diff] [blame] | 1379 | if (writeback_mode(&cache->features) && |
| 1380 | !avoid && bio_writes_complete_block(cache, bio)) { |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1381 | issue_overwrite(mg, bio); |
| 1382 | return; |
| 1383 | } |
| 1384 | } |
| 1385 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1386 | avoid ? avoid_copy(mg) : issue_copy(mg); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1387 | } |
| 1388 | |
| 1389 | static void complete_migration(struct dm_cache_migration *mg) |
| 1390 | { |
| 1391 | if (mg->err) |
| 1392 | migration_failure(mg); |
| 1393 | else |
| 1394 | migration_success_pre_commit(mg); |
| 1395 | } |
| 1396 | |
| 1397 | static void process_migrations(struct cache *cache, struct list_head *head, |
| 1398 | void (*fn)(struct dm_cache_migration *)) |
| 1399 | { |
| 1400 | unsigned long flags; |
| 1401 | struct list_head list; |
| 1402 | struct dm_cache_migration *mg, *tmp; |
| 1403 | |
| 1404 | INIT_LIST_HEAD(&list); |
| 1405 | spin_lock_irqsave(&cache->lock, flags); |
| 1406 | list_splice_init(head, &list); |
| 1407 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1408 | |
| 1409 | list_for_each_entry_safe(mg, tmp, &list, list) |
| 1410 | fn(mg); |
| 1411 | } |
| 1412 | |
| 1413 | static void __queue_quiesced_migration(struct dm_cache_migration *mg) |
| 1414 | { |
| 1415 | list_add_tail(&mg->list, &mg->cache->quiesced_migrations); |
| 1416 | } |
| 1417 | |
| 1418 | static void queue_quiesced_migration(struct dm_cache_migration *mg) |
| 1419 | { |
| 1420 | unsigned long flags; |
| 1421 | struct cache *cache = mg->cache; |
| 1422 | |
| 1423 | spin_lock_irqsave(&cache->lock, flags); |
| 1424 | __queue_quiesced_migration(mg); |
| 1425 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1426 | |
| 1427 | wake_worker(cache); |
| 1428 | } |
| 1429 | |
| 1430 | static void queue_quiesced_migrations(struct cache *cache, struct list_head *work) |
| 1431 | { |
| 1432 | unsigned long flags; |
| 1433 | struct dm_cache_migration *mg, *tmp; |
| 1434 | |
| 1435 | spin_lock_irqsave(&cache->lock, flags); |
| 1436 | list_for_each_entry_safe(mg, tmp, work, list) |
| 1437 | __queue_quiesced_migration(mg); |
| 1438 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1439 | |
| 1440 | wake_worker(cache); |
| 1441 | } |
| 1442 | |
| 1443 | static void check_for_quiesced_migrations(struct cache *cache, |
| 1444 | struct per_bio_data *pb) |
| 1445 | { |
| 1446 | struct list_head work; |
| 1447 | |
| 1448 | if (!pb->all_io_entry) |
| 1449 | return; |
| 1450 | |
| 1451 | INIT_LIST_HEAD(&work); |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1452 | dm_deferred_entry_dec(pb->all_io_entry, &work); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1453 | |
| 1454 | if (!list_empty(&work)) |
| 1455 | queue_quiesced_migrations(cache, &work); |
| 1456 | } |
| 1457 | |
| 1458 | static void quiesce_migration(struct dm_cache_migration *mg) |
| 1459 | { |
| 1460 | if (!dm_deferred_set_add_work(mg->cache->all_io_ds, &mg->list)) |
| 1461 | queue_quiesced_migration(mg); |
| 1462 | } |
| 1463 | |
| 1464 | static void promote(struct cache *cache, struct prealloc *structs, |
| 1465 | dm_oblock_t oblock, dm_cblock_t cblock, |
| 1466 | struct dm_bio_prison_cell *cell) |
| 1467 | { |
| 1468 | struct dm_cache_migration *mg = prealloc_get_migration(structs); |
| 1469 | |
| 1470 | mg->err = false; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1471 | mg->discard = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1472 | mg->writeback = false; |
| 1473 | mg->demote = false; |
| 1474 | mg->promote = true; |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1475 | mg->requeue_holder = true; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1476 | mg->invalidate = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1477 | mg->cache = cache; |
| 1478 | mg->new_oblock = oblock; |
| 1479 | mg->cblock = cblock; |
| 1480 | mg->old_ocell = NULL; |
| 1481 | mg->new_ocell = cell; |
| 1482 | mg->start_jiffies = jiffies; |
| 1483 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1484 | inc_io_migrations(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1485 | quiesce_migration(mg); |
| 1486 | } |
| 1487 | |
| 1488 | static void writeback(struct cache *cache, struct prealloc *structs, |
| 1489 | dm_oblock_t oblock, dm_cblock_t cblock, |
| 1490 | struct dm_bio_prison_cell *cell) |
| 1491 | { |
| 1492 | struct dm_cache_migration *mg = prealloc_get_migration(structs); |
| 1493 | |
| 1494 | mg->err = false; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1495 | mg->discard = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1496 | mg->writeback = true; |
| 1497 | mg->demote = false; |
| 1498 | mg->promote = false; |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1499 | mg->requeue_holder = true; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1500 | mg->invalidate = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1501 | mg->cache = cache; |
| 1502 | mg->old_oblock = oblock; |
| 1503 | mg->cblock = cblock; |
| 1504 | mg->old_ocell = cell; |
| 1505 | mg->new_ocell = NULL; |
| 1506 | mg->start_jiffies = jiffies; |
| 1507 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1508 | inc_io_migrations(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1509 | quiesce_migration(mg); |
| 1510 | } |
| 1511 | |
| 1512 | static void demote_then_promote(struct cache *cache, struct prealloc *structs, |
| 1513 | dm_oblock_t old_oblock, dm_oblock_t new_oblock, |
| 1514 | dm_cblock_t cblock, |
| 1515 | struct dm_bio_prison_cell *old_ocell, |
| 1516 | struct dm_bio_prison_cell *new_ocell) |
| 1517 | { |
| 1518 | struct dm_cache_migration *mg = prealloc_get_migration(structs); |
| 1519 | |
| 1520 | mg->err = false; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1521 | mg->discard = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1522 | mg->writeback = false; |
| 1523 | mg->demote = true; |
| 1524 | mg->promote = true; |
Joe Thornber | c9d28d5 | 2013-10-31 13:55:48 -0400 | [diff] [blame] | 1525 | mg->requeue_holder = true; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1526 | mg->invalidate = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1527 | mg->cache = cache; |
| 1528 | mg->old_oblock = old_oblock; |
| 1529 | mg->new_oblock = new_oblock; |
| 1530 | mg->cblock = cblock; |
| 1531 | mg->old_ocell = old_ocell; |
| 1532 | mg->new_ocell = new_ocell; |
| 1533 | mg->start_jiffies = jiffies; |
| 1534 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1535 | inc_io_migrations(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1536 | quiesce_migration(mg); |
| 1537 | } |
| 1538 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1539 | /* |
| 1540 | * Invalidate a cache entry. No writeback occurs; any changes in the cache |
| 1541 | * block are thrown away. |
| 1542 | */ |
| 1543 | static void invalidate(struct cache *cache, struct prealloc *structs, |
| 1544 | dm_oblock_t oblock, dm_cblock_t cblock, |
| 1545 | struct dm_bio_prison_cell *cell) |
| 1546 | { |
| 1547 | struct dm_cache_migration *mg = prealloc_get_migration(structs); |
| 1548 | |
| 1549 | mg->err = false; |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1550 | mg->discard = false; |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1551 | mg->writeback = false; |
| 1552 | mg->demote = true; |
| 1553 | mg->promote = false; |
| 1554 | mg->requeue_holder = true; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 1555 | mg->invalidate = true; |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1556 | mg->cache = cache; |
| 1557 | mg->old_oblock = oblock; |
| 1558 | mg->cblock = cblock; |
| 1559 | mg->old_ocell = cell; |
| 1560 | mg->new_ocell = NULL; |
| 1561 | mg->start_jiffies = jiffies; |
| 1562 | |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1563 | inc_io_migrations(cache); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1564 | quiesce_migration(mg); |
| 1565 | } |
| 1566 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1567 | static void discard(struct cache *cache, struct prealloc *structs, |
| 1568 | struct dm_bio_prison_cell *cell) |
| 1569 | { |
| 1570 | struct dm_cache_migration *mg = prealloc_get_migration(structs); |
| 1571 | |
| 1572 | mg->err = false; |
| 1573 | mg->discard = true; |
| 1574 | mg->writeback = false; |
| 1575 | mg->demote = false; |
| 1576 | mg->promote = false; |
| 1577 | mg->requeue_holder = false; |
| 1578 | mg->invalidate = false; |
| 1579 | mg->cache = cache; |
| 1580 | mg->old_ocell = NULL; |
| 1581 | mg->new_ocell = cell; |
| 1582 | mg->start_jiffies = jiffies; |
| 1583 | |
| 1584 | quiesce_migration(mg); |
| 1585 | } |
| 1586 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1587 | /*---------------------------------------------------------------- |
| 1588 | * bio processing |
| 1589 | *--------------------------------------------------------------*/ |
| 1590 | static void defer_bio(struct cache *cache, struct bio *bio) |
| 1591 | { |
| 1592 | unsigned long flags; |
| 1593 | |
| 1594 | spin_lock_irqsave(&cache->lock, flags); |
| 1595 | bio_list_add(&cache->deferred_bios, bio); |
| 1596 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1597 | |
| 1598 | wake_worker(cache); |
| 1599 | } |
| 1600 | |
| 1601 | static void process_flush_bio(struct cache *cache, struct bio *bio) |
| 1602 | { |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 1603 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 1604 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1605 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1606 | BUG_ON(bio->bi_iter.bi_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1607 | if (!pb->req_nr) |
| 1608 | remap_to_origin(cache, bio); |
| 1609 | else |
| 1610 | remap_to_cache(cache, bio, 0); |
| 1611 | |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1612 | /* |
| 1613 | * REQ_FLUSH is not directed at any particular block so we don't |
| 1614 | * need to inc_ds(). REQ_FUA's are split into a write + REQ_FLUSH |
| 1615 | * by dm-core. |
| 1616 | */ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1617 | issue(cache, bio); |
| 1618 | } |
| 1619 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1620 | static void process_discard_bio(struct cache *cache, struct prealloc *structs, |
| 1621 | struct bio *bio) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1622 | { |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1623 | int r; |
| 1624 | dm_dblock_t b, e; |
| 1625 | struct dm_bio_prison_cell *cell_prealloc, *new_ocell; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1626 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1627 | calc_discard_block_range(cache, bio, &b, &e); |
| 1628 | if (b == e) { |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1629 | bio_endio(bio); |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1630 | return; |
| 1631 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1632 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1633 | cell_prealloc = prealloc_get_cell(structs); |
| 1634 | r = bio_detain_range(cache, dblock_to_oblock(cache, b), dblock_to_oblock(cache, e), bio, cell_prealloc, |
| 1635 | (cell_free_fn) prealloc_put_cell, |
| 1636 | structs, &new_ocell); |
| 1637 | if (r > 0) |
| 1638 | return; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1639 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1640 | discard(cache, structs, new_ocell); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1641 | } |
| 1642 | |
| 1643 | static bool spare_migration_bandwidth(struct cache *cache) |
| 1644 | { |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 1645 | sector_t current_volume = (atomic_read(&cache->nr_io_migrations) + 1) * |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1646 | cache->sectors_per_block; |
| 1647 | return current_volume < cache->migration_threshold; |
| 1648 | } |
| 1649 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1650 | static void inc_hit_counter(struct cache *cache, struct bio *bio) |
| 1651 | { |
| 1652 | atomic_inc(bio_data_dir(bio) == READ ? |
| 1653 | &cache->stats.read_hit : &cache->stats.write_hit); |
| 1654 | } |
| 1655 | |
| 1656 | static void inc_miss_counter(struct cache *cache, struct bio *bio) |
| 1657 | { |
| 1658 | atomic_inc(bio_data_dir(bio) == READ ? |
| 1659 | &cache->stats.read_miss : &cache->stats.write_miss); |
| 1660 | } |
| 1661 | |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1662 | /*----------------------------------------------------------------*/ |
| 1663 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1664 | struct inc_detail { |
| 1665 | struct cache *cache; |
| 1666 | struct bio_list bios_for_issue; |
| 1667 | struct bio_list unhandled_bios; |
| 1668 | bool any_writes; |
| 1669 | }; |
| 1670 | |
| 1671 | static void inc_fn(void *context, struct dm_bio_prison_cell *cell) |
| 1672 | { |
| 1673 | struct bio *bio; |
| 1674 | struct inc_detail *detail = context; |
| 1675 | struct cache *cache = detail->cache; |
| 1676 | |
| 1677 | inc_ds(cache, cell->holder, cell); |
| 1678 | if (bio_data_dir(cell->holder) == WRITE) |
| 1679 | detail->any_writes = true; |
| 1680 | |
| 1681 | while ((bio = bio_list_pop(&cell->bios))) { |
| 1682 | if (discard_or_flush(bio)) { |
| 1683 | bio_list_add(&detail->unhandled_bios, bio); |
| 1684 | continue; |
| 1685 | } |
| 1686 | |
| 1687 | if (bio_data_dir(bio) == WRITE) |
| 1688 | detail->any_writes = true; |
| 1689 | |
| 1690 | bio_list_add(&detail->bios_for_issue, bio); |
| 1691 | inc_ds(cache, bio, cell); |
| 1692 | } |
| 1693 | } |
| 1694 | |
| 1695 | // FIXME: refactor these two |
| 1696 | static void remap_cell_to_origin_clear_discard(struct cache *cache, |
| 1697 | struct dm_bio_prison_cell *cell, |
| 1698 | dm_oblock_t oblock, bool issue_holder) |
| 1699 | { |
| 1700 | struct bio *bio; |
| 1701 | unsigned long flags; |
| 1702 | struct inc_detail detail; |
| 1703 | |
| 1704 | detail.cache = cache; |
| 1705 | bio_list_init(&detail.bios_for_issue); |
| 1706 | bio_list_init(&detail.unhandled_bios); |
| 1707 | detail.any_writes = false; |
| 1708 | |
| 1709 | spin_lock_irqsave(&cache->lock, flags); |
| 1710 | dm_cell_visit_release(cache->prison, inc_fn, &detail, cell); |
| 1711 | bio_list_merge(&cache->deferred_bios, &detail.unhandled_bios); |
| 1712 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1713 | |
| 1714 | remap_to_origin(cache, cell->holder); |
| 1715 | if (issue_holder) |
| 1716 | issue(cache, cell->holder); |
| 1717 | else |
| 1718 | accounted_begin(cache, cell->holder); |
| 1719 | |
| 1720 | if (detail.any_writes) |
| 1721 | clear_discard(cache, oblock_to_dblock(cache, oblock)); |
| 1722 | |
| 1723 | while ((bio = bio_list_pop(&detail.bios_for_issue))) { |
| 1724 | remap_to_origin(cache, bio); |
| 1725 | issue(cache, bio); |
| 1726 | } |
Joe Thornber | 9153df7 | 2015-08-31 18:20:08 +0100 | [diff] [blame] | 1727 | |
| 1728 | free_prison_cell(cache, cell); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1729 | } |
| 1730 | |
| 1731 | static void remap_cell_to_cache_dirty(struct cache *cache, struct dm_bio_prison_cell *cell, |
| 1732 | dm_oblock_t oblock, dm_cblock_t cblock, bool issue_holder) |
| 1733 | { |
| 1734 | struct bio *bio; |
| 1735 | unsigned long flags; |
| 1736 | struct inc_detail detail; |
| 1737 | |
| 1738 | detail.cache = cache; |
| 1739 | bio_list_init(&detail.bios_for_issue); |
| 1740 | bio_list_init(&detail.unhandled_bios); |
| 1741 | detail.any_writes = false; |
| 1742 | |
| 1743 | spin_lock_irqsave(&cache->lock, flags); |
| 1744 | dm_cell_visit_release(cache->prison, inc_fn, &detail, cell); |
| 1745 | bio_list_merge(&cache->deferred_bios, &detail.unhandled_bios); |
| 1746 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1747 | |
| 1748 | remap_to_cache(cache, cell->holder, cblock); |
| 1749 | if (issue_holder) |
| 1750 | issue(cache, cell->holder); |
| 1751 | else |
| 1752 | accounted_begin(cache, cell->holder); |
| 1753 | |
| 1754 | if (detail.any_writes) { |
| 1755 | set_dirty(cache, oblock, cblock); |
| 1756 | clear_discard(cache, oblock_to_dblock(cache, oblock)); |
| 1757 | } |
| 1758 | |
| 1759 | while ((bio = bio_list_pop(&detail.bios_for_issue))) { |
| 1760 | remap_to_cache(cache, bio, cblock); |
| 1761 | issue(cache, bio); |
| 1762 | } |
Joe Thornber | 9153df7 | 2015-08-31 18:20:08 +0100 | [diff] [blame] | 1763 | |
| 1764 | free_prison_cell(cache, cell); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1765 | } |
| 1766 | |
| 1767 | /*----------------------------------------------------------------*/ |
| 1768 | |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1769 | struct old_oblock_lock { |
| 1770 | struct policy_locker locker; |
| 1771 | struct cache *cache; |
| 1772 | struct prealloc *structs; |
| 1773 | struct dm_bio_prison_cell *cell; |
| 1774 | }; |
| 1775 | |
| 1776 | static int null_locker(struct policy_locker *locker, dm_oblock_t b) |
| 1777 | { |
| 1778 | /* This should never be called */ |
| 1779 | BUG(); |
| 1780 | return 0; |
| 1781 | } |
| 1782 | |
| 1783 | static int cell_locker(struct policy_locker *locker, dm_oblock_t b) |
| 1784 | { |
| 1785 | struct old_oblock_lock *l = container_of(locker, struct old_oblock_lock, locker); |
| 1786 | struct dm_bio_prison_cell *cell_prealloc = prealloc_get_cell(l->structs); |
| 1787 | |
| 1788 | return bio_detain(l->cache, b, NULL, cell_prealloc, |
| 1789 | (cell_free_fn) prealloc_put_cell, |
| 1790 | l->structs, &l->cell); |
| 1791 | } |
| 1792 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1793 | static void process_cell(struct cache *cache, struct prealloc *structs, |
| 1794 | struct dm_bio_prison_cell *new_ocell) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1795 | { |
| 1796 | int r; |
| 1797 | bool release_cell = true; |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1798 | struct bio *bio = new_ocell->holder; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1799 | dm_oblock_t block = get_bio_block(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1800 | struct policy_result lookup_result; |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1801 | bool passthrough = passthrough_mode(&cache->features); |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 1802 | bool fast_promotion, can_migrate; |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1803 | struct old_oblock_lock ool; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1804 | |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 1805 | fast_promotion = is_discarded_oblock(cache, block) || bio_writes_complete_block(cache, bio); |
| 1806 | can_migrate = !passthrough && (fast_promotion || spare_migration_bandwidth(cache)); |
Joe Thornber | 43c32bf | 2014-11-25 13:14:57 +0000 | [diff] [blame] | 1807 | |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1808 | ool.locker.fn = cell_locker; |
| 1809 | ool.cache = cache; |
| 1810 | ool.structs = structs; |
| 1811 | ool.cell = NULL; |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 1812 | r = policy_map(cache->policy, block, true, can_migrate, fast_promotion, |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1813 | bio, &ool.locker, &lookup_result); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1814 | |
| 1815 | if (r == -EWOULDBLOCK) |
| 1816 | /* migration has been denied */ |
| 1817 | lookup_result.op = POLICY_MISS; |
| 1818 | |
| 1819 | switch (lookup_result.op) { |
| 1820 | case POLICY_HIT: |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1821 | if (passthrough) { |
| 1822 | inc_miss_counter(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1823 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1824 | /* |
| 1825 | * Passthrough always maps to the origin, |
| 1826 | * invalidating any cache blocks that are written |
| 1827 | * to. |
| 1828 | */ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1829 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1830 | if (bio_data_dir(bio) == WRITE) { |
| 1831 | atomic_inc(&cache->stats.demotion); |
| 1832 | invalidate(cache, structs, block, lookup_result.cblock, new_ocell); |
| 1833 | release_cell = false; |
| 1834 | |
| 1835 | } else { |
| 1836 | /* FIXME: factor out issue_origin() */ |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1837 | remap_to_origin_clear_discard(cache, bio, block); |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1838 | inc_and_issue(cache, bio, new_ocell); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1839 | } |
| 1840 | } else { |
| 1841 | inc_hit_counter(cache, bio); |
| 1842 | |
| 1843 | if (bio_data_dir(bio) == WRITE && |
| 1844 | writethrough_mode(&cache->features) && |
| 1845 | !is_dirty(cache, lookup_result.cblock)) { |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1846 | remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1847 | inc_and_issue(cache, bio, new_ocell); |
| 1848 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1849 | } else { |
| 1850 | remap_cell_to_cache_dirty(cache, new_ocell, block, lookup_result.cblock, true); |
| 1851 | release_cell = false; |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 1852 | } |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 1853 | } |
| 1854 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1855 | break; |
| 1856 | |
| 1857 | case POLICY_MISS: |
| 1858 | inc_miss_counter(cache, bio); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1859 | remap_cell_to_origin_clear_discard(cache, new_ocell, block, true); |
| 1860 | release_cell = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1861 | break; |
| 1862 | |
| 1863 | case POLICY_NEW: |
| 1864 | atomic_inc(&cache->stats.promotion); |
| 1865 | promote(cache, structs, block, lookup_result.cblock, new_ocell); |
| 1866 | release_cell = false; |
| 1867 | break; |
| 1868 | |
| 1869 | case POLICY_REPLACE: |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1870 | atomic_inc(&cache->stats.demotion); |
| 1871 | atomic_inc(&cache->stats.promotion); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1872 | demote_then_promote(cache, structs, lookup_result.old_oblock, |
| 1873 | block, lookup_result.cblock, |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 1874 | ool.cell, new_ocell); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1875 | release_cell = false; |
| 1876 | break; |
| 1877 | |
| 1878 | default: |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 1879 | DMERR_LIMIT("%s: %s: erroring bio, unknown policy op: %u", |
| 1880 | cache_device_name(cache), __func__, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1881 | (unsigned) lookup_result.op); |
| 1882 | bio_io_error(bio); |
| 1883 | } |
| 1884 | |
| 1885 | if (release_cell) |
| 1886 | cell_defer(cache, new_ocell, false); |
| 1887 | } |
| 1888 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1889 | static void process_bio(struct cache *cache, struct prealloc *structs, |
| 1890 | struct bio *bio) |
| 1891 | { |
| 1892 | int r; |
| 1893 | dm_oblock_t block = get_bio_block(cache, bio); |
| 1894 | struct dm_bio_prison_cell *cell_prealloc, *new_ocell; |
| 1895 | |
| 1896 | /* |
| 1897 | * Check to see if that block is currently migrating. |
| 1898 | */ |
| 1899 | cell_prealloc = prealloc_get_cell(structs); |
| 1900 | r = bio_detain(cache, block, bio, cell_prealloc, |
| 1901 | (cell_free_fn) prealloc_put_cell, |
| 1902 | structs, &new_ocell); |
| 1903 | if (r > 0) |
| 1904 | return; |
| 1905 | |
| 1906 | process_cell(cache, structs, new_ocell); |
| 1907 | } |
| 1908 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1909 | static int need_commit_due_to_time(struct cache *cache) |
| 1910 | { |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1911 | return jiffies < cache->last_commit_jiffies || |
| 1912 | jiffies > cache->last_commit_jiffies + COMMIT_PERIOD; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1913 | } |
| 1914 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1915 | /* |
| 1916 | * A non-zero return indicates read_only or fail_io mode. |
| 1917 | */ |
| 1918 | static int commit(struct cache *cache, bool clean_shutdown) |
| 1919 | { |
| 1920 | int r; |
| 1921 | |
| 1922 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 1923 | return -EINVAL; |
| 1924 | |
| 1925 | atomic_inc(&cache->stats.commit_count); |
| 1926 | r = dm_cache_commit(cache->cmd, clean_shutdown); |
| 1927 | if (r) |
| 1928 | metadata_operation_failed(cache, "dm_cache_commit", r); |
| 1929 | |
| 1930 | return r; |
| 1931 | } |
| 1932 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1933 | static int commit_if_needed(struct cache *cache) |
| 1934 | { |
Heinz Mauelshagen | ffcbcb6 | 2013-10-14 17:24:43 +0200 | [diff] [blame] | 1935 | int r = 0; |
| 1936 | |
| 1937 | if ((cache->commit_requested || need_commit_due_to_time(cache)) && |
| 1938 | dm_cache_changed_this_transaction(cache->cmd)) { |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 1939 | r = commit(cache, false); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1940 | cache->commit_requested = false; |
Heinz Mauelshagen | ffcbcb6 | 2013-10-14 17:24:43 +0200 | [diff] [blame] | 1941 | cache->last_commit_jiffies = jiffies; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1942 | } |
| 1943 | |
Heinz Mauelshagen | ffcbcb6 | 2013-10-14 17:24:43 +0200 | [diff] [blame] | 1944 | return r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1945 | } |
| 1946 | |
| 1947 | static void process_deferred_bios(struct cache *cache) |
| 1948 | { |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 1949 | bool prealloc_used = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1950 | unsigned long flags; |
| 1951 | struct bio_list bios; |
| 1952 | struct bio *bio; |
| 1953 | struct prealloc structs; |
| 1954 | |
| 1955 | memset(&structs, 0, sizeof(structs)); |
| 1956 | bio_list_init(&bios); |
| 1957 | |
| 1958 | spin_lock_irqsave(&cache->lock, flags); |
| 1959 | bio_list_merge(&bios, &cache->deferred_bios); |
| 1960 | bio_list_init(&cache->deferred_bios); |
| 1961 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1962 | |
| 1963 | while (!bio_list_empty(&bios)) { |
| 1964 | /* |
| 1965 | * If we've got no free migration structs, and processing |
| 1966 | * this bio might require one, we pause until there are some |
| 1967 | * prepared mappings to process. |
| 1968 | */ |
Mike Snitzer | 795e633 | 2015-07-29 13:48:23 -0400 | [diff] [blame] | 1969 | prealloc_used = true; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1970 | if (prealloc_data_structs(cache, &structs)) { |
| 1971 | spin_lock_irqsave(&cache->lock, flags); |
| 1972 | bio_list_merge(&cache->deferred_bios, &bios); |
| 1973 | spin_unlock_irqrestore(&cache->lock, flags); |
| 1974 | break; |
| 1975 | } |
| 1976 | |
| 1977 | bio = bio_list_pop(&bios); |
| 1978 | |
| 1979 | if (bio->bi_rw & REQ_FLUSH) |
| 1980 | process_flush_bio(cache, bio); |
| 1981 | else if (bio->bi_rw & REQ_DISCARD) |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 1982 | process_discard_bio(cache, &structs, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1983 | else |
| 1984 | process_bio(cache, &structs, bio); |
| 1985 | } |
| 1986 | |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 1987 | if (prealloc_used) |
| 1988 | prealloc_free_structs(cache, &structs); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 1989 | } |
| 1990 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1991 | static void process_deferred_cells(struct cache *cache) |
| 1992 | { |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 1993 | bool prealloc_used = false; |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 1994 | unsigned long flags; |
| 1995 | struct dm_bio_prison_cell *cell, *tmp; |
| 1996 | struct list_head cells; |
| 1997 | struct prealloc structs; |
| 1998 | |
| 1999 | memset(&structs, 0, sizeof(structs)); |
| 2000 | |
| 2001 | INIT_LIST_HEAD(&cells); |
| 2002 | |
| 2003 | spin_lock_irqsave(&cache->lock, flags); |
| 2004 | list_splice_init(&cache->deferred_cells, &cells); |
| 2005 | spin_unlock_irqrestore(&cache->lock, flags); |
| 2006 | |
| 2007 | list_for_each_entry_safe(cell, tmp, &cells, user_list) { |
| 2008 | /* |
| 2009 | * If we've got no free migration structs, and processing |
| 2010 | * this bio might require one, we pause until there are some |
| 2011 | * prepared mappings to process. |
| 2012 | */ |
Mike Snitzer | 795e633 | 2015-07-29 13:48:23 -0400 | [diff] [blame] | 2013 | prealloc_used = true; |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2014 | if (prealloc_data_structs(cache, &structs)) { |
| 2015 | spin_lock_irqsave(&cache->lock, flags); |
| 2016 | list_splice(&cells, &cache->deferred_cells); |
| 2017 | spin_unlock_irqrestore(&cache->lock, flags); |
| 2018 | break; |
| 2019 | } |
| 2020 | |
| 2021 | process_cell(cache, &structs, cell); |
| 2022 | } |
| 2023 | |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 2024 | if (prealloc_used) |
| 2025 | prealloc_free_structs(cache, &structs); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2026 | } |
| 2027 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2028 | static void process_deferred_flush_bios(struct cache *cache, bool submit_bios) |
| 2029 | { |
| 2030 | unsigned long flags; |
| 2031 | struct bio_list bios; |
| 2032 | struct bio *bio; |
| 2033 | |
| 2034 | bio_list_init(&bios); |
| 2035 | |
| 2036 | spin_lock_irqsave(&cache->lock, flags); |
| 2037 | bio_list_merge(&bios, &cache->deferred_flush_bios); |
| 2038 | bio_list_init(&cache->deferred_flush_bios); |
| 2039 | spin_unlock_irqrestore(&cache->lock, flags); |
| 2040 | |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 2041 | /* |
| 2042 | * These bios have already been through inc_ds() |
| 2043 | */ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2044 | while ((bio = bio_list_pop(&bios))) |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 2045 | submit_bios ? accounted_request(cache, bio) : bio_io_error(bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2046 | } |
| 2047 | |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 2048 | static void process_deferred_writethrough_bios(struct cache *cache) |
| 2049 | { |
| 2050 | unsigned long flags; |
| 2051 | struct bio_list bios; |
| 2052 | struct bio *bio; |
| 2053 | |
| 2054 | bio_list_init(&bios); |
| 2055 | |
| 2056 | spin_lock_irqsave(&cache->lock, flags); |
| 2057 | bio_list_merge(&bios, &cache->deferred_writethrough_bios); |
| 2058 | bio_list_init(&cache->deferred_writethrough_bios); |
| 2059 | spin_unlock_irqrestore(&cache->lock, flags); |
| 2060 | |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 2061 | /* |
| 2062 | * These bios have already been through inc_ds() |
| 2063 | */ |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 2064 | while ((bio = bio_list_pop(&bios))) |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 2065 | accounted_request(cache, bio); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 2066 | } |
| 2067 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2068 | static void writeback_some_dirty_blocks(struct cache *cache) |
| 2069 | { |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 2070 | bool prealloc_used = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2071 | dm_oblock_t oblock; |
| 2072 | dm_cblock_t cblock; |
| 2073 | struct prealloc structs; |
| 2074 | struct dm_bio_prison_cell *old_ocell; |
Joe Thornber | 20f6814 | 2015-05-15 15:20:09 +0100 | [diff] [blame] | 2075 | bool busy = !iot_idle_for(&cache->origin_tracker, HZ); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2076 | |
| 2077 | memset(&structs, 0, sizeof(structs)); |
| 2078 | |
| 2079 | while (spare_migration_bandwidth(cache)) { |
Mike Snitzer | e782eff | 2015-07-16 21:26:10 -0400 | [diff] [blame] | 2080 | if (policy_writeback_work(cache->policy, &oblock, &cblock, busy)) |
| 2081 | break; /* no work to do */ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2082 | |
Mike Snitzer | 795e633 | 2015-07-29 13:48:23 -0400 | [diff] [blame] | 2083 | prealloc_used = true; |
Mike Snitzer | e782eff | 2015-07-16 21:26:10 -0400 | [diff] [blame] | 2084 | if (prealloc_data_structs(cache, &structs) || |
| 2085 | get_cell(cache, oblock, &structs, &old_ocell)) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2086 | policy_set_dirty(cache->policy, oblock); |
| 2087 | break; |
| 2088 | } |
| 2089 | |
| 2090 | writeback(cache, &structs, oblock, cblock, old_ocell); |
| 2091 | } |
| 2092 | |
Mike Snitzer | 665022d | 2015-07-16 21:48:55 -0400 | [diff] [blame] | 2093 | if (prealloc_used) |
| 2094 | prealloc_free_structs(cache, &structs); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2095 | } |
| 2096 | |
| 2097 | /*---------------------------------------------------------------- |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2098 | * Invalidations. |
| 2099 | * Dropping something from the cache *without* writing back. |
| 2100 | *--------------------------------------------------------------*/ |
| 2101 | |
| 2102 | static void process_invalidation_request(struct cache *cache, struct invalidation_request *req) |
| 2103 | { |
| 2104 | int r = 0; |
| 2105 | uint64_t begin = from_cblock(req->cblocks->begin); |
| 2106 | uint64_t end = from_cblock(req->cblocks->end); |
| 2107 | |
| 2108 | while (begin != end) { |
| 2109 | r = policy_remove_cblock(cache->policy, to_cblock(begin)); |
| 2110 | if (!r) { |
| 2111 | r = dm_cache_remove_mapping(cache->cmd, to_cblock(begin)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 2112 | if (r) { |
| 2113 | metadata_operation_failed(cache, "dm_cache_remove_mapping", r); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2114 | break; |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 2115 | } |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2116 | |
| 2117 | } else if (r == -ENODATA) { |
| 2118 | /* harmless, already unmapped */ |
| 2119 | r = 0; |
| 2120 | |
| 2121 | } else { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 2122 | DMERR("%s: policy_remove_cblock failed", cache_device_name(cache)); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2123 | break; |
| 2124 | } |
| 2125 | |
| 2126 | begin++; |
| 2127 | } |
| 2128 | |
| 2129 | cache->commit_requested = true; |
| 2130 | |
| 2131 | req->err = r; |
| 2132 | atomic_set(&req->complete, 1); |
| 2133 | |
| 2134 | wake_up(&req->result_wait); |
| 2135 | } |
| 2136 | |
| 2137 | static void process_invalidation_requests(struct cache *cache) |
| 2138 | { |
| 2139 | struct list_head list; |
| 2140 | struct invalidation_request *req, *tmp; |
| 2141 | |
| 2142 | INIT_LIST_HEAD(&list); |
| 2143 | spin_lock(&cache->invalidation_lock); |
| 2144 | list_splice_init(&cache->invalidation_requests, &list); |
| 2145 | spin_unlock(&cache->invalidation_lock); |
| 2146 | |
| 2147 | list_for_each_entry_safe (req, tmp, &list, list) |
| 2148 | process_invalidation_request(cache, req); |
| 2149 | } |
| 2150 | |
| 2151 | /*---------------------------------------------------------------- |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2152 | * Main worker loop |
| 2153 | *--------------------------------------------------------------*/ |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2154 | static bool is_quiescing(struct cache *cache) |
| 2155 | { |
Joe Thornber | 238f836 | 2013-10-30 17:29:30 +0000 | [diff] [blame] | 2156 | return atomic_read(&cache->quiescing); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2157 | } |
| 2158 | |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2159 | static void ack_quiescing(struct cache *cache) |
| 2160 | { |
| 2161 | if (is_quiescing(cache)) { |
| 2162 | atomic_inc(&cache->quiescing_ack); |
| 2163 | wake_up(&cache->quiescing_wait); |
| 2164 | } |
| 2165 | } |
| 2166 | |
| 2167 | static void wait_for_quiescing_ack(struct cache *cache) |
| 2168 | { |
| 2169 | wait_event(cache->quiescing_wait, atomic_read(&cache->quiescing_ack)); |
| 2170 | } |
| 2171 | |
| 2172 | static void start_quiescing(struct cache *cache) |
| 2173 | { |
Joe Thornber | 238f836 | 2013-10-30 17:29:30 +0000 | [diff] [blame] | 2174 | atomic_inc(&cache->quiescing); |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2175 | wait_for_quiescing_ack(cache); |
| 2176 | } |
| 2177 | |
| 2178 | static void stop_quiescing(struct cache *cache) |
| 2179 | { |
Joe Thornber | 238f836 | 2013-10-30 17:29:30 +0000 | [diff] [blame] | 2180 | atomic_set(&cache->quiescing, 0); |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2181 | atomic_set(&cache->quiescing_ack, 0); |
| 2182 | } |
| 2183 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2184 | static void wait_for_migrations(struct cache *cache) |
| 2185 | { |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 2186 | wait_event(cache->migration_wait, !atomic_read(&cache->nr_allocated_migrations)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2187 | } |
| 2188 | |
| 2189 | static void stop_worker(struct cache *cache) |
| 2190 | { |
| 2191 | cancel_delayed_work(&cache->waker); |
| 2192 | flush_workqueue(cache->wq); |
| 2193 | } |
| 2194 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2195 | static void requeue_deferred_cells(struct cache *cache) |
| 2196 | { |
| 2197 | unsigned long flags; |
| 2198 | struct list_head cells; |
| 2199 | struct dm_bio_prison_cell *cell, *tmp; |
| 2200 | |
| 2201 | INIT_LIST_HEAD(&cells); |
| 2202 | spin_lock_irqsave(&cache->lock, flags); |
| 2203 | list_splice_init(&cache->deferred_cells, &cells); |
| 2204 | spin_unlock_irqrestore(&cache->lock, flags); |
| 2205 | |
| 2206 | list_for_each_entry_safe(cell, tmp, &cells, user_list) |
| 2207 | cell_requeue(cache, cell); |
| 2208 | } |
| 2209 | |
| 2210 | static void requeue_deferred_bios(struct cache *cache) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2211 | { |
| 2212 | struct bio *bio; |
| 2213 | struct bio_list bios; |
| 2214 | |
| 2215 | bio_list_init(&bios); |
| 2216 | bio_list_merge(&bios, &cache->deferred_bios); |
| 2217 | bio_list_init(&cache->deferred_bios); |
| 2218 | |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 2219 | while ((bio = bio_list_pop(&bios))) { |
| 2220 | bio->bi_error = DM_ENDIO_REQUEUE; |
| 2221 | bio_endio(bio); |
| 2222 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2223 | } |
| 2224 | |
| 2225 | static int more_work(struct cache *cache) |
| 2226 | { |
| 2227 | if (is_quiescing(cache)) |
| 2228 | return !list_empty(&cache->quiesced_migrations) || |
| 2229 | !list_empty(&cache->completed_migrations) || |
| 2230 | !list_empty(&cache->need_commit_migrations); |
| 2231 | else |
| 2232 | return !bio_list_empty(&cache->deferred_bios) || |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2233 | !list_empty(&cache->deferred_cells) || |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2234 | !bio_list_empty(&cache->deferred_flush_bios) || |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 2235 | !bio_list_empty(&cache->deferred_writethrough_bios) || |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2236 | !list_empty(&cache->quiesced_migrations) || |
| 2237 | !list_empty(&cache->completed_migrations) || |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2238 | !list_empty(&cache->need_commit_migrations) || |
| 2239 | cache->invalidate; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2240 | } |
| 2241 | |
| 2242 | static void do_worker(struct work_struct *ws) |
| 2243 | { |
| 2244 | struct cache *cache = container_of(ws, struct cache, worker); |
| 2245 | |
| 2246 | do { |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2247 | if (!is_quiescing(cache)) { |
| 2248 | writeback_some_dirty_blocks(cache); |
| 2249 | process_deferred_writethrough_bios(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2250 | process_deferred_bios(cache); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2251 | process_deferred_cells(cache); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2252 | process_invalidation_requests(cache); |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2253 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2254 | |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 2255 | process_migrations(cache, &cache->quiesced_migrations, issue_copy_or_discard); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2256 | process_migrations(cache, &cache->completed_migrations, complete_migration); |
| 2257 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2258 | if (commit_if_needed(cache)) { |
| 2259 | process_deferred_flush_bios(cache, false); |
Joe Thornber | 304affa | 2014-06-24 15:36:58 -0400 | [diff] [blame] | 2260 | process_migrations(cache, &cache->need_commit_migrations, migration_failure); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2261 | } else { |
| 2262 | process_deferred_flush_bios(cache, true); |
| 2263 | process_migrations(cache, &cache->need_commit_migrations, |
| 2264 | migration_success_post_commit); |
| 2265 | } |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2266 | |
| 2267 | ack_quiescing(cache); |
| 2268 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2269 | } while (more_work(cache)); |
| 2270 | } |
| 2271 | |
| 2272 | /* |
| 2273 | * We want to commit periodically so that not too much |
| 2274 | * unwritten metadata builds up. |
| 2275 | */ |
| 2276 | static void do_waker(struct work_struct *ws) |
| 2277 | { |
| 2278 | struct cache *cache = container_of(to_delayed_work(ws), struct cache, waker); |
Joe Thornber | fba1010 | 2015-05-29 10:20:56 +0100 | [diff] [blame] | 2279 | policy_tick(cache->policy, true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2280 | wake_worker(cache); |
| 2281 | queue_delayed_work(cache->wq, &cache->waker, COMMIT_PERIOD); |
| 2282 | } |
| 2283 | |
| 2284 | /*----------------------------------------------------------------*/ |
| 2285 | |
| 2286 | static int is_congested(struct dm_dev *dev, int bdi_bits) |
| 2287 | { |
| 2288 | struct request_queue *q = bdev_get_queue(dev->bdev); |
| 2289 | return bdi_congested(&q->backing_dev_info, bdi_bits); |
| 2290 | } |
| 2291 | |
| 2292 | static int cache_is_congested(struct dm_target_callbacks *cb, int bdi_bits) |
| 2293 | { |
| 2294 | struct cache *cache = container_of(cb, struct cache, callbacks); |
| 2295 | |
| 2296 | return is_congested(cache->origin_dev, bdi_bits) || |
| 2297 | is_congested(cache->cache_dev, bdi_bits); |
| 2298 | } |
| 2299 | |
| 2300 | /*---------------------------------------------------------------- |
| 2301 | * Target methods |
| 2302 | *--------------------------------------------------------------*/ |
| 2303 | |
| 2304 | /* |
| 2305 | * This function gets called on the error paths of the constructor, so we |
| 2306 | * have to cope with a partially initialised struct. |
| 2307 | */ |
| 2308 | static void destroy(struct cache *cache) |
| 2309 | { |
| 2310 | unsigned i; |
| 2311 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2312 | if (cache->migration_pool) |
| 2313 | mempool_destroy(cache->migration_pool); |
| 2314 | |
| 2315 | if (cache->all_io_ds) |
| 2316 | dm_deferred_set_destroy(cache->all_io_ds); |
| 2317 | |
| 2318 | if (cache->prison) |
| 2319 | dm_bio_prison_destroy(cache->prison); |
| 2320 | |
| 2321 | if (cache->wq) |
| 2322 | destroy_workqueue(cache->wq); |
| 2323 | |
| 2324 | if (cache->dirty_bitset) |
| 2325 | free_bitset(cache->dirty_bitset); |
| 2326 | |
| 2327 | if (cache->discard_bitset) |
| 2328 | free_bitset(cache->discard_bitset); |
| 2329 | |
| 2330 | if (cache->copier) |
| 2331 | dm_kcopyd_client_destroy(cache->copier); |
| 2332 | |
| 2333 | if (cache->cmd) |
| 2334 | dm_cache_metadata_close(cache->cmd); |
| 2335 | |
| 2336 | if (cache->metadata_dev) |
| 2337 | dm_put_device(cache->ti, cache->metadata_dev); |
| 2338 | |
| 2339 | if (cache->origin_dev) |
| 2340 | dm_put_device(cache->ti, cache->origin_dev); |
| 2341 | |
| 2342 | if (cache->cache_dev) |
| 2343 | dm_put_device(cache->ti, cache->cache_dev); |
| 2344 | |
| 2345 | if (cache->policy) |
| 2346 | dm_cache_policy_destroy(cache->policy); |
| 2347 | |
| 2348 | for (i = 0; i < cache->nr_ctr_args ; i++) |
| 2349 | kfree(cache->ctr_args[i]); |
| 2350 | kfree(cache->ctr_args); |
| 2351 | |
| 2352 | kfree(cache); |
| 2353 | } |
| 2354 | |
| 2355 | static void cache_dtr(struct dm_target *ti) |
| 2356 | { |
| 2357 | struct cache *cache = ti->private; |
| 2358 | |
| 2359 | destroy(cache); |
| 2360 | } |
| 2361 | |
| 2362 | static sector_t get_dev_size(struct dm_dev *dev) |
| 2363 | { |
| 2364 | return i_size_read(dev->bdev->bd_inode) >> SECTOR_SHIFT; |
| 2365 | } |
| 2366 | |
| 2367 | /*----------------------------------------------------------------*/ |
| 2368 | |
| 2369 | /* |
| 2370 | * Construct a cache device mapping. |
| 2371 | * |
| 2372 | * cache <metadata dev> <cache dev> <origin dev> <block size> |
| 2373 | * <#feature args> [<feature arg>]* |
| 2374 | * <policy> <#policy args> [<policy arg>]* |
| 2375 | * |
| 2376 | * metadata dev : fast device holding the persistent metadata |
| 2377 | * cache dev : fast device holding cached data blocks |
| 2378 | * origin dev : slow device holding original data blocks |
| 2379 | * block size : cache unit size in sectors |
| 2380 | * |
| 2381 | * #feature args : number of feature arguments passed |
| 2382 | * feature args : writethrough. (The default is writeback.) |
| 2383 | * |
| 2384 | * policy : the replacement policy to use |
| 2385 | * #policy args : an even number of policy arguments corresponding |
| 2386 | * to key/value pairs passed to the policy |
| 2387 | * policy args : key/value pairs passed to the policy |
| 2388 | * E.g. 'sequential_threshold 1024' |
| 2389 | * See cache-policies.txt for details. |
| 2390 | * |
| 2391 | * Optional feature arguments are: |
| 2392 | * writethrough : write through caching that prohibits cache block |
| 2393 | * content from being different from origin block content. |
| 2394 | * Without this argument, the default behaviour is to write |
| 2395 | * back cache block contents later for performance reasons, |
| 2396 | * so they may differ from the corresponding origin blocks. |
| 2397 | */ |
| 2398 | struct cache_args { |
| 2399 | struct dm_target *ti; |
| 2400 | |
| 2401 | struct dm_dev *metadata_dev; |
| 2402 | |
| 2403 | struct dm_dev *cache_dev; |
| 2404 | sector_t cache_sectors; |
| 2405 | |
| 2406 | struct dm_dev *origin_dev; |
| 2407 | sector_t origin_sectors; |
| 2408 | |
| 2409 | uint32_t block_size; |
| 2410 | |
| 2411 | const char *policy_name; |
| 2412 | int policy_argc; |
| 2413 | const char **policy_argv; |
| 2414 | |
| 2415 | struct cache_features features; |
| 2416 | }; |
| 2417 | |
| 2418 | static void destroy_cache_args(struct cache_args *ca) |
| 2419 | { |
| 2420 | if (ca->metadata_dev) |
| 2421 | dm_put_device(ca->ti, ca->metadata_dev); |
| 2422 | |
| 2423 | if (ca->cache_dev) |
| 2424 | dm_put_device(ca->ti, ca->cache_dev); |
| 2425 | |
| 2426 | if (ca->origin_dev) |
| 2427 | dm_put_device(ca->ti, ca->origin_dev); |
| 2428 | |
| 2429 | kfree(ca); |
| 2430 | } |
| 2431 | |
| 2432 | static bool at_least_one_arg(struct dm_arg_set *as, char **error) |
| 2433 | { |
| 2434 | if (!as->argc) { |
| 2435 | *error = "Insufficient args"; |
| 2436 | return false; |
| 2437 | } |
| 2438 | |
| 2439 | return true; |
| 2440 | } |
| 2441 | |
| 2442 | static int parse_metadata_dev(struct cache_args *ca, struct dm_arg_set *as, |
| 2443 | char **error) |
| 2444 | { |
| 2445 | int r; |
| 2446 | sector_t metadata_dev_size; |
| 2447 | char b[BDEVNAME_SIZE]; |
| 2448 | |
| 2449 | if (!at_least_one_arg(as, error)) |
| 2450 | return -EINVAL; |
| 2451 | |
| 2452 | r = dm_get_device(ca->ti, dm_shift_arg(as), FMODE_READ | FMODE_WRITE, |
| 2453 | &ca->metadata_dev); |
| 2454 | if (r) { |
| 2455 | *error = "Error opening metadata device"; |
| 2456 | return r; |
| 2457 | } |
| 2458 | |
| 2459 | metadata_dev_size = get_dev_size(ca->metadata_dev); |
| 2460 | if (metadata_dev_size > DM_CACHE_METADATA_MAX_SECTORS_WARNING) |
| 2461 | DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.", |
| 2462 | bdevname(ca->metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS); |
| 2463 | |
| 2464 | return 0; |
| 2465 | } |
| 2466 | |
| 2467 | static int parse_cache_dev(struct cache_args *ca, struct dm_arg_set *as, |
| 2468 | char **error) |
| 2469 | { |
| 2470 | int r; |
| 2471 | |
| 2472 | if (!at_least_one_arg(as, error)) |
| 2473 | return -EINVAL; |
| 2474 | |
| 2475 | r = dm_get_device(ca->ti, dm_shift_arg(as), FMODE_READ | FMODE_WRITE, |
| 2476 | &ca->cache_dev); |
| 2477 | if (r) { |
| 2478 | *error = "Error opening cache device"; |
| 2479 | return r; |
| 2480 | } |
| 2481 | ca->cache_sectors = get_dev_size(ca->cache_dev); |
| 2482 | |
| 2483 | return 0; |
| 2484 | } |
| 2485 | |
| 2486 | static int parse_origin_dev(struct cache_args *ca, struct dm_arg_set *as, |
| 2487 | char **error) |
| 2488 | { |
| 2489 | int r; |
| 2490 | |
| 2491 | if (!at_least_one_arg(as, error)) |
| 2492 | return -EINVAL; |
| 2493 | |
| 2494 | r = dm_get_device(ca->ti, dm_shift_arg(as), FMODE_READ | FMODE_WRITE, |
| 2495 | &ca->origin_dev); |
| 2496 | if (r) { |
| 2497 | *error = "Error opening origin device"; |
| 2498 | return r; |
| 2499 | } |
| 2500 | |
| 2501 | ca->origin_sectors = get_dev_size(ca->origin_dev); |
| 2502 | if (ca->ti->len > ca->origin_sectors) { |
| 2503 | *error = "Device size larger than cached device"; |
| 2504 | return -EINVAL; |
| 2505 | } |
| 2506 | |
| 2507 | return 0; |
| 2508 | } |
| 2509 | |
| 2510 | static int parse_block_size(struct cache_args *ca, struct dm_arg_set *as, |
| 2511 | char **error) |
| 2512 | { |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 2513 | unsigned long block_size; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2514 | |
| 2515 | if (!at_least_one_arg(as, error)) |
| 2516 | return -EINVAL; |
| 2517 | |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 2518 | if (kstrtoul(dm_shift_arg(as), 10, &block_size) || !block_size || |
| 2519 | block_size < DATA_DEV_BLOCK_SIZE_MIN_SECTORS || |
| 2520 | block_size > DATA_DEV_BLOCK_SIZE_MAX_SECTORS || |
| 2521 | block_size & (DATA_DEV_BLOCK_SIZE_MIN_SECTORS - 1)) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2522 | *error = "Invalid data block size"; |
| 2523 | return -EINVAL; |
| 2524 | } |
| 2525 | |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 2526 | if (block_size > ca->cache_sectors) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2527 | *error = "Data block size is larger than the cache device"; |
| 2528 | return -EINVAL; |
| 2529 | } |
| 2530 | |
Mike Snitzer | 0547304 | 2013-08-16 10:54:19 -0400 | [diff] [blame] | 2531 | ca->block_size = block_size; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2532 | |
| 2533 | return 0; |
| 2534 | } |
| 2535 | |
| 2536 | static void init_features(struct cache_features *cf) |
| 2537 | { |
| 2538 | cf->mode = CM_WRITE; |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 2539 | cf->io_mode = CM_IO_WRITEBACK; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2540 | } |
| 2541 | |
| 2542 | static int parse_features(struct cache_args *ca, struct dm_arg_set *as, |
| 2543 | char **error) |
| 2544 | { |
| 2545 | static struct dm_arg _args[] = { |
| 2546 | {0, 1, "Invalid number of cache feature arguments"}, |
| 2547 | }; |
| 2548 | |
| 2549 | int r; |
| 2550 | unsigned argc; |
| 2551 | const char *arg; |
| 2552 | struct cache_features *cf = &ca->features; |
| 2553 | |
| 2554 | init_features(cf); |
| 2555 | |
| 2556 | r = dm_read_arg_group(_args, as, &argc, error); |
| 2557 | if (r) |
| 2558 | return -EINVAL; |
| 2559 | |
| 2560 | while (argc--) { |
| 2561 | arg = dm_shift_arg(as); |
| 2562 | |
| 2563 | if (!strcasecmp(arg, "writeback")) |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 2564 | cf->io_mode = CM_IO_WRITEBACK; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2565 | |
| 2566 | else if (!strcasecmp(arg, "writethrough")) |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 2567 | cf->io_mode = CM_IO_WRITETHROUGH; |
| 2568 | |
| 2569 | else if (!strcasecmp(arg, "passthrough")) |
| 2570 | cf->io_mode = CM_IO_PASSTHROUGH; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2571 | |
| 2572 | else { |
| 2573 | *error = "Unrecognised cache feature requested"; |
| 2574 | return -EINVAL; |
| 2575 | } |
| 2576 | } |
| 2577 | |
| 2578 | return 0; |
| 2579 | } |
| 2580 | |
| 2581 | static int parse_policy(struct cache_args *ca, struct dm_arg_set *as, |
| 2582 | char **error) |
| 2583 | { |
| 2584 | static struct dm_arg _args[] = { |
| 2585 | {0, 1024, "Invalid number of policy arguments"}, |
| 2586 | }; |
| 2587 | |
| 2588 | int r; |
| 2589 | |
| 2590 | if (!at_least_one_arg(as, error)) |
| 2591 | return -EINVAL; |
| 2592 | |
| 2593 | ca->policy_name = dm_shift_arg(as); |
| 2594 | |
| 2595 | r = dm_read_arg_group(_args, as, &ca->policy_argc, error); |
| 2596 | if (r) |
| 2597 | return -EINVAL; |
| 2598 | |
| 2599 | ca->policy_argv = (const char **)as->argv; |
| 2600 | dm_consume_args(as, ca->policy_argc); |
| 2601 | |
| 2602 | return 0; |
| 2603 | } |
| 2604 | |
| 2605 | static int parse_cache_args(struct cache_args *ca, int argc, char **argv, |
| 2606 | char **error) |
| 2607 | { |
| 2608 | int r; |
| 2609 | struct dm_arg_set as; |
| 2610 | |
| 2611 | as.argc = argc; |
| 2612 | as.argv = argv; |
| 2613 | |
| 2614 | r = parse_metadata_dev(ca, &as, error); |
| 2615 | if (r) |
| 2616 | return r; |
| 2617 | |
| 2618 | r = parse_cache_dev(ca, &as, error); |
| 2619 | if (r) |
| 2620 | return r; |
| 2621 | |
| 2622 | r = parse_origin_dev(ca, &as, error); |
| 2623 | if (r) |
| 2624 | return r; |
| 2625 | |
| 2626 | r = parse_block_size(ca, &as, error); |
| 2627 | if (r) |
| 2628 | return r; |
| 2629 | |
| 2630 | r = parse_features(ca, &as, error); |
| 2631 | if (r) |
| 2632 | return r; |
| 2633 | |
| 2634 | r = parse_policy(ca, &as, error); |
| 2635 | if (r) |
| 2636 | return r; |
| 2637 | |
| 2638 | return 0; |
| 2639 | } |
| 2640 | |
| 2641 | /*----------------------------------------------------------------*/ |
| 2642 | |
| 2643 | static struct kmem_cache *migration_cache; |
| 2644 | |
Alasdair G Kergon | 2c73c47 | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2645 | #define NOT_CORE_OPTION 1 |
| 2646 | |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2647 | static int process_config_option(struct cache *cache, const char *key, const char *value) |
Alasdair G Kergon | 2c73c47 | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2648 | { |
| 2649 | unsigned long tmp; |
| 2650 | |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2651 | if (!strcasecmp(key, "migration_threshold")) { |
| 2652 | if (kstrtoul(value, 10, &tmp)) |
Alasdair G Kergon | 2c73c47 | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2653 | return -EINVAL; |
| 2654 | |
| 2655 | cache->migration_threshold = tmp; |
| 2656 | return 0; |
| 2657 | } |
| 2658 | |
| 2659 | return NOT_CORE_OPTION; |
| 2660 | } |
| 2661 | |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2662 | static int set_config_value(struct cache *cache, const char *key, const char *value) |
| 2663 | { |
| 2664 | int r = process_config_option(cache, key, value); |
| 2665 | |
| 2666 | if (r == NOT_CORE_OPTION) |
| 2667 | r = policy_set_config_value(cache->policy, key, value); |
| 2668 | |
| 2669 | if (r) |
| 2670 | DMWARN("bad config value for %s: %s", key, value); |
| 2671 | |
| 2672 | return r; |
| 2673 | } |
| 2674 | |
| 2675 | static int set_config_values(struct cache *cache, int argc, const char **argv) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2676 | { |
| 2677 | int r = 0; |
| 2678 | |
| 2679 | if (argc & 1) { |
| 2680 | DMWARN("Odd number of policy arguments given but they should be <key> <value> pairs."); |
| 2681 | return -EINVAL; |
| 2682 | } |
| 2683 | |
| 2684 | while (argc) { |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2685 | r = set_config_value(cache, argv[0], argv[1]); |
| 2686 | if (r) |
| 2687 | break; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2688 | |
| 2689 | argc -= 2; |
| 2690 | argv += 2; |
| 2691 | } |
| 2692 | |
| 2693 | return r; |
| 2694 | } |
| 2695 | |
| 2696 | static int create_cache_policy(struct cache *cache, struct cache_args *ca, |
| 2697 | char **error) |
| 2698 | { |
Mikulas Patocka | 4cb3e1d | 2013-10-01 18:35:39 -0400 | [diff] [blame] | 2699 | struct dm_cache_policy *p = dm_cache_policy_create(ca->policy_name, |
| 2700 | cache->cache_size, |
| 2701 | cache->origin_sectors, |
| 2702 | cache->sectors_per_block); |
| 2703 | if (IS_ERR(p)) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2704 | *error = "Error creating cache's policy"; |
Mikulas Patocka | 4cb3e1d | 2013-10-01 18:35:39 -0400 | [diff] [blame] | 2705 | return PTR_ERR(p); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2706 | } |
Mikulas Patocka | 4cb3e1d | 2013-10-01 18:35:39 -0400 | [diff] [blame] | 2707 | cache->policy = p; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2708 | |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2709 | return 0; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2710 | } |
| 2711 | |
Joe Thornber | 08b1845 | 2014-11-06 14:38:01 +0000 | [diff] [blame] | 2712 | /* |
Joe Thornber | 2bb812d | 2014-11-26 16:07:50 +0000 | [diff] [blame] | 2713 | * We want the discard block size to be at least the size of the cache |
| 2714 | * block size and have no more than 2^14 discard blocks across the origin. |
Joe Thornber | 08b1845 | 2014-11-06 14:38:01 +0000 | [diff] [blame] | 2715 | */ |
| 2716 | #define MAX_DISCARD_BLOCKS (1 << 14) |
| 2717 | |
| 2718 | static bool too_many_discard_blocks(sector_t discard_block_size, |
| 2719 | sector_t origin_size) |
| 2720 | { |
| 2721 | (void) sector_div(origin_size, discard_block_size); |
| 2722 | |
| 2723 | return origin_size > MAX_DISCARD_BLOCKS; |
| 2724 | } |
| 2725 | |
| 2726 | static sector_t calculate_discard_block_size(sector_t cache_block_size, |
| 2727 | sector_t origin_size) |
| 2728 | { |
Joe Thornber | 2bb812d | 2014-11-26 16:07:50 +0000 | [diff] [blame] | 2729 | sector_t discard_block_size = cache_block_size; |
Joe Thornber | 08b1845 | 2014-11-06 14:38:01 +0000 | [diff] [blame] | 2730 | |
| 2731 | if (origin_size) |
| 2732 | while (too_many_discard_blocks(discard_block_size, origin_size)) |
| 2733 | discard_block_size *= 2; |
| 2734 | |
| 2735 | return discard_block_size; |
| 2736 | } |
| 2737 | |
Joe Thornber | d1d9220 | 2014-11-11 11:58:32 +0000 | [diff] [blame] | 2738 | static void set_cache_size(struct cache *cache, dm_cblock_t size) |
| 2739 | { |
| 2740 | dm_block_t nr_blocks = from_cblock(size); |
| 2741 | |
| 2742 | if (nr_blocks > (1 << 20) && cache->cache_size != size) |
| 2743 | DMWARN_LIMIT("You have created a cache device with a lot of individual cache blocks (%llu)\n" |
| 2744 | "All these mappings can consume a lot of kernel memory, and take some time to read/write.\n" |
| 2745 | "Please consider increasing the cache block size to reduce the overall cache block count.", |
| 2746 | (unsigned long long) nr_blocks); |
| 2747 | |
| 2748 | cache->cache_size = size; |
| 2749 | } |
| 2750 | |
Joe Thornber | f8350da | 2013-05-10 14:37:16 +0100 | [diff] [blame] | 2751 | #define DEFAULT_MIGRATION_THRESHOLD 2048 |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2752 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2753 | static int cache_create(struct cache_args *ca, struct cache **result) |
| 2754 | { |
| 2755 | int r = 0; |
| 2756 | char **error = &ca->ti->error; |
| 2757 | struct cache *cache; |
| 2758 | struct dm_target *ti = ca->ti; |
| 2759 | dm_block_t origin_blocks; |
| 2760 | struct dm_cache_metadata *cmd; |
| 2761 | bool may_format = ca->features.mode == CM_WRITE; |
| 2762 | |
| 2763 | cache = kzalloc(sizeof(*cache), GFP_KERNEL); |
| 2764 | if (!cache) |
| 2765 | return -ENOMEM; |
| 2766 | |
| 2767 | cache->ti = ca->ti; |
| 2768 | ti->private = cache; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2769 | ti->num_flush_bios = 2; |
| 2770 | ti->flush_supported = true; |
| 2771 | |
| 2772 | ti->num_discard_bios = 1; |
| 2773 | ti->discards_supported = true; |
| 2774 | ti->discard_zeroes_data_unsupported = true; |
Joe Thornber | 2572629 | 2014-11-24 14:05:16 +0000 | [diff] [blame] | 2775 | ti->split_discard_bios = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2776 | |
Joe Thornber | 8c5008f | 2013-05-10 14:37:18 +0100 | [diff] [blame] | 2777 | cache->features = ca->features; |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 2778 | ti->per_bio_data_size = get_per_bio_data_size(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2779 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2780 | cache->callbacks.congested_fn = cache_is_congested; |
| 2781 | dm_table_add_target_callbacks(ti->table, &cache->callbacks); |
| 2782 | |
| 2783 | cache->metadata_dev = ca->metadata_dev; |
| 2784 | cache->origin_dev = ca->origin_dev; |
| 2785 | cache->cache_dev = ca->cache_dev; |
| 2786 | |
| 2787 | ca->metadata_dev = ca->origin_dev = ca->cache_dev = NULL; |
| 2788 | |
| 2789 | /* FIXME: factor out this whole section */ |
| 2790 | origin_blocks = cache->origin_sectors = ca->origin_sectors; |
Joe Thornber | 414dd67 | 2013-03-20 17:21:25 +0000 | [diff] [blame] | 2791 | origin_blocks = block_div(origin_blocks, ca->block_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2792 | cache->origin_blocks = to_oblock(origin_blocks); |
| 2793 | |
| 2794 | cache->sectors_per_block = ca->block_size; |
| 2795 | if (dm_set_target_max_io_len(ti, cache->sectors_per_block)) { |
| 2796 | r = -EINVAL; |
| 2797 | goto bad; |
| 2798 | } |
| 2799 | |
| 2800 | if (ca->block_size & (ca->block_size - 1)) { |
| 2801 | dm_block_t cache_size = ca->cache_sectors; |
| 2802 | |
| 2803 | cache->sectors_per_block_shift = -1; |
Joe Thornber | 414dd67 | 2013-03-20 17:21:25 +0000 | [diff] [blame] | 2804 | cache_size = block_div(cache_size, ca->block_size); |
Joe Thornber | d1d9220 | 2014-11-11 11:58:32 +0000 | [diff] [blame] | 2805 | set_cache_size(cache, to_cblock(cache_size)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2806 | } else { |
| 2807 | cache->sectors_per_block_shift = __ffs(ca->block_size); |
Joe Thornber | d1d9220 | 2014-11-11 11:58:32 +0000 | [diff] [blame] | 2808 | set_cache_size(cache, to_cblock(ca->cache_sectors >> cache->sectors_per_block_shift)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2809 | } |
| 2810 | |
| 2811 | r = create_cache_policy(cache, ca, error); |
| 2812 | if (r) |
| 2813 | goto bad; |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2814 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2815 | cache->policy_nr_args = ca->policy_argc; |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 2816 | cache->migration_threshold = DEFAULT_MIGRATION_THRESHOLD; |
| 2817 | |
| 2818 | r = set_config_values(cache, ca->policy_argc, ca->policy_argv); |
| 2819 | if (r) { |
| 2820 | *error = "Error setting cache policy's config values"; |
| 2821 | goto bad; |
| 2822 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2823 | |
| 2824 | cmd = dm_cache_metadata_open(cache->metadata_dev->bdev, |
| 2825 | ca->block_size, may_format, |
| 2826 | dm_cache_policy_get_hint_size(cache->policy)); |
| 2827 | if (IS_ERR(cmd)) { |
| 2828 | *error = "Error creating metadata object"; |
| 2829 | r = PTR_ERR(cmd); |
| 2830 | goto bad; |
| 2831 | } |
| 2832 | cache->cmd = cmd; |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 2833 | set_cache_mode(cache, CM_WRITE); |
| 2834 | if (get_cache_mode(cache) != CM_WRITE) { |
| 2835 | *error = "Unable to get write access to metadata, please check/repair metadata."; |
| 2836 | r = -EINVAL; |
| 2837 | goto bad; |
| 2838 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2839 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 2840 | if (passthrough_mode(&cache->features)) { |
| 2841 | bool all_clean; |
| 2842 | |
| 2843 | r = dm_cache_metadata_all_clean(cache->cmd, &all_clean); |
| 2844 | if (r) { |
| 2845 | *error = "dm_cache_metadata_all_clean() failed"; |
| 2846 | goto bad; |
| 2847 | } |
| 2848 | |
| 2849 | if (!all_clean) { |
| 2850 | *error = "Cannot enter passthrough mode unless all blocks are clean"; |
| 2851 | r = -EINVAL; |
| 2852 | goto bad; |
| 2853 | } |
| 2854 | } |
| 2855 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2856 | spin_lock_init(&cache->lock); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 2857 | INIT_LIST_HEAD(&cache->deferred_cells); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2858 | bio_list_init(&cache->deferred_bios); |
| 2859 | bio_list_init(&cache->deferred_flush_bios); |
Joe Thornber | e2e74d6 | 2013-03-20 17:21:27 +0000 | [diff] [blame] | 2860 | bio_list_init(&cache->deferred_writethrough_bios); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2861 | INIT_LIST_HEAD(&cache->quiesced_migrations); |
| 2862 | INIT_LIST_HEAD(&cache->completed_migrations); |
| 2863 | INIT_LIST_HEAD(&cache->need_commit_migrations); |
Joe Thornber | a59db67 | 2015-01-23 10:16:16 +0000 | [diff] [blame] | 2864 | atomic_set(&cache->nr_allocated_migrations, 0); |
| 2865 | atomic_set(&cache->nr_io_migrations, 0); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2866 | init_waitqueue_head(&cache->migration_wait); |
| 2867 | |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2868 | init_waitqueue_head(&cache->quiescing_wait); |
Joe Thornber | 238f836 | 2013-10-30 17:29:30 +0000 | [diff] [blame] | 2869 | atomic_set(&cache->quiescing, 0); |
Joe Thornber | 66cb191 | 2013-10-30 17:11:58 +0000 | [diff] [blame] | 2870 | atomic_set(&cache->quiescing_ack, 0); |
| 2871 | |
Wei Yongjun | fa4d683 | 2013-05-10 14:37:14 +0100 | [diff] [blame] | 2872 | r = -ENOMEM; |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 2873 | atomic_set(&cache->nr_dirty, 0); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2874 | cache->dirty_bitset = alloc_bitset(from_cblock(cache->cache_size)); |
| 2875 | if (!cache->dirty_bitset) { |
| 2876 | *error = "could not allocate dirty bitset"; |
| 2877 | goto bad; |
| 2878 | } |
| 2879 | clear_bitset(cache->dirty_bitset, from_cblock(cache->cache_size)); |
| 2880 | |
Joe Thornber | 08b1845 | 2014-11-06 14:38:01 +0000 | [diff] [blame] | 2881 | cache->discard_block_size = |
| 2882 | calculate_discard_block_size(cache->sectors_per_block, |
| 2883 | cache->origin_sectors); |
Joe Thornber | 2572629 | 2014-11-24 14:05:16 +0000 | [diff] [blame] | 2884 | cache->discard_nr_blocks = to_dblock(dm_sector_div_up(cache->origin_sectors, |
| 2885 | cache->discard_block_size)); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 2886 | cache->discard_bitset = alloc_bitset(from_dblock(cache->discard_nr_blocks)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2887 | if (!cache->discard_bitset) { |
| 2888 | *error = "could not allocate discard bitset"; |
| 2889 | goto bad; |
| 2890 | } |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 2891 | clear_bitset(cache->discard_bitset, from_dblock(cache->discard_nr_blocks)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2892 | |
| 2893 | cache->copier = dm_kcopyd_client_create(&dm_kcopyd_throttle); |
| 2894 | if (IS_ERR(cache->copier)) { |
| 2895 | *error = "could not create kcopyd client"; |
| 2896 | r = PTR_ERR(cache->copier); |
| 2897 | goto bad; |
| 2898 | } |
| 2899 | |
| 2900 | cache->wq = alloc_ordered_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM); |
| 2901 | if (!cache->wq) { |
| 2902 | *error = "could not create workqueue for metadata object"; |
| 2903 | goto bad; |
| 2904 | } |
| 2905 | INIT_WORK(&cache->worker, do_worker); |
| 2906 | INIT_DELAYED_WORK(&cache->waker, do_waker); |
| 2907 | cache->last_commit_jiffies = jiffies; |
| 2908 | |
Joe Thornber | a195db2 | 2014-10-06 16:30:06 -0400 | [diff] [blame] | 2909 | cache->prison = dm_bio_prison_create(); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2910 | if (!cache->prison) { |
| 2911 | *error = "could not create bio prison"; |
| 2912 | goto bad; |
| 2913 | } |
| 2914 | |
| 2915 | cache->all_io_ds = dm_deferred_set_create(); |
| 2916 | if (!cache->all_io_ds) { |
| 2917 | *error = "could not create all_io deferred set"; |
| 2918 | goto bad; |
| 2919 | } |
| 2920 | |
| 2921 | cache->migration_pool = mempool_create_slab_pool(MIGRATION_POOL_SIZE, |
| 2922 | migration_cache); |
| 2923 | if (!cache->migration_pool) { |
| 2924 | *error = "Error creating cache's migration mempool"; |
| 2925 | goto bad; |
| 2926 | } |
| 2927 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2928 | cache->need_tick_bio = true; |
| 2929 | cache->sized = false; |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2930 | cache->invalidate = false; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2931 | cache->commit_requested = false; |
| 2932 | cache->loaded_mappings = false; |
| 2933 | cache->loaded_discards = false; |
| 2934 | |
| 2935 | load_stats(cache); |
| 2936 | |
| 2937 | atomic_set(&cache->stats.demotion, 0); |
| 2938 | atomic_set(&cache->stats.promotion, 0); |
| 2939 | atomic_set(&cache->stats.copies_avoided, 0); |
| 2940 | atomic_set(&cache->stats.cache_cell_clash, 0); |
| 2941 | atomic_set(&cache->stats.commit_count, 0); |
| 2942 | atomic_set(&cache->stats.discard_count, 0); |
| 2943 | |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 2944 | spin_lock_init(&cache->invalidation_lock); |
| 2945 | INIT_LIST_HEAD(&cache->invalidation_requests); |
| 2946 | |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 2947 | iot_init(&cache->origin_tracker); |
| 2948 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 2949 | *result = cache; |
| 2950 | return 0; |
| 2951 | |
| 2952 | bad: |
| 2953 | destroy(cache); |
| 2954 | return r; |
| 2955 | } |
| 2956 | |
| 2957 | static int copy_ctr_args(struct cache *cache, int argc, const char **argv) |
| 2958 | { |
| 2959 | unsigned i; |
| 2960 | const char **copy; |
| 2961 | |
| 2962 | copy = kcalloc(argc, sizeof(*copy), GFP_KERNEL); |
| 2963 | if (!copy) |
| 2964 | return -ENOMEM; |
| 2965 | for (i = 0; i < argc; i++) { |
| 2966 | copy[i] = kstrdup(argv[i], GFP_KERNEL); |
| 2967 | if (!copy[i]) { |
| 2968 | while (i--) |
| 2969 | kfree(copy[i]); |
| 2970 | kfree(copy); |
| 2971 | return -ENOMEM; |
| 2972 | } |
| 2973 | } |
| 2974 | |
| 2975 | cache->nr_ctr_args = argc; |
| 2976 | cache->ctr_args = copy; |
| 2977 | |
| 2978 | return 0; |
| 2979 | } |
| 2980 | |
| 2981 | static int cache_ctr(struct dm_target *ti, unsigned argc, char **argv) |
| 2982 | { |
| 2983 | int r = -EINVAL; |
| 2984 | struct cache_args *ca; |
| 2985 | struct cache *cache = NULL; |
| 2986 | |
| 2987 | ca = kzalloc(sizeof(*ca), GFP_KERNEL); |
| 2988 | if (!ca) { |
| 2989 | ti->error = "Error allocating memory for cache"; |
| 2990 | return -ENOMEM; |
| 2991 | } |
| 2992 | ca->ti = ti; |
| 2993 | |
| 2994 | r = parse_cache_args(ca, argc, argv, &ti->error); |
| 2995 | if (r) |
| 2996 | goto out; |
| 2997 | |
| 2998 | r = cache_create(ca, &cache); |
Heinz Mauelshagen | 617a0b8 | 2013-03-20 17:21:26 +0000 | [diff] [blame] | 2999 | if (r) |
| 3000 | goto out; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3001 | |
| 3002 | r = copy_ctr_args(cache, argc - 3, (const char **)argv + 3); |
| 3003 | if (r) { |
| 3004 | destroy(cache); |
| 3005 | goto out; |
| 3006 | } |
| 3007 | |
| 3008 | ti->private = cache; |
| 3009 | |
| 3010 | out: |
| 3011 | destroy_cache_args(ca); |
| 3012 | return r; |
| 3013 | } |
| 3014 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3015 | /*----------------------------------------------------------------*/ |
| 3016 | |
| 3017 | static int cache_map(struct dm_target *ti, struct bio *bio) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3018 | { |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3019 | struct cache *cache = ti->private; |
| 3020 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3021 | int r; |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3022 | struct dm_bio_prison_cell *cell = NULL; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3023 | dm_oblock_t block = get_bio_block(cache, bio); |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 3024 | size_t pb_data_size = get_per_bio_data_size(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3025 | bool can_migrate = false; |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 3026 | bool fast_promotion; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3027 | struct policy_result lookup_result; |
Heinz Mauelshagen | e893fba | 2014-03-12 16:13:39 +0100 | [diff] [blame] | 3028 | struct per_bio_data *pb = init_per_bio_data(bio, pb_data_size); |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 3029 | struct old_oblock_lock ool; |
| 3030 | |
| 3031 | ool.locker.fn = null_locker; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3032 | |
Heinz Mauelshagen | e893fba | 2014-03-12 16:13:39 +0100 | [diff] [blame] | 3033 | if (unlikely(from_oblock(block) >= from_oblock(cache->origin_blocks))) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3034 | /* |
| 3035 | * This can only occur if the io goes to a partial block at |
| 3036 | * the end of the origin device. We don't cache these. |
| 3037 | * Just remap to the origin and carry on. |
| 3038 | */ |
Heinz Mauelshagen | e893fba | 2014-03-12 16:13:39 +0100 | [diff] [blame] | 3039 | remap_to_origin(cache, bio); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3040 | accounted_begin(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3041 | return DM_MAPIO_REMAPPED; |
| 3042 | } |
| 3043 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3044 | if (discard_or_flush(bio)) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3045 | defer_bio(cache, bio); |
| 3046 | return DM_MAPIO_SUBMITTED; |
| 3047 | } |
| 3048 | |
| 3049 | /* |
| 3050 | * Check to see if that block is currently migrating. |
| 3051 | */ |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3052 | cell = alloc_prison_cell(cache); |
| 3053 | if (!cell) { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3054 | defer_bio(cache, bio); |
| 3055 | return DM_MAPIO_SUBMITTED; |
| 3056 | } |
| 3057 | |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3058 | r = bio_detain(cache, block, bio, cell, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3059 | (cell_free_fn) free_prison_cell, |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3060 | cache, &cell); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3061 | if (r) { |
| 3062 | if (r < 0) |
| 3063 | defer_bio(cache, bio); |
| 3064 | |
| 3065 | return DM_MAPIO_SUBMITTED; |
| 3066 | } |
| 3067 | |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 3068 | fast_promotion = is_discarded_oblock(cache, block) || bio_writes_complete_block(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3069 | |
Joe Thornber | 4077525 | 2015-05-15 15:29:58 +0100 | [diff] [blame] | 3070 | r = policy_map(cache->policy, block, false, can_migrate, fast_promotion, |
Joe Thornber | fb4100a | 2015-05-20 10:30:32 +0100 | [diff] [blame] | 3071 | bio, &ool.locker, &lookup_result); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3072 | if (r == -EWOULDBLOCK) { |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3073 | cell_defer(cache, cell, true); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3074 | return DM_MAPIO_SUBMITTED; |
| 3075 | |
| 3076 | } else if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3077 | DMERR_LIMIT("%s: Unexpected return from cache replacement policy: %d", |
| 3078 | cache_device_name(cache), r); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3079 | cell_defer(cache, cell, false); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3080 | bio_io_error(bio); |
| 3081 | return DM_MAPIO_SUBMITTED; |
| 3082 | } |
| 3083 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3084 | r = DM_MAPIO_REMAPPED; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3085 | switch (lookup_result.op) { |
| 3086 | case POLICY_HIT: |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3087 | if (passthrough_mode(&cache->features)) { |
| 3088 | if (bio_data_dir(bio) == WRITE) { |
| 3089 | /* |
| 3090 | * We need to invalidate this block, so |
| 3091 | * defer for the worker thread. |
| 3092 | */ |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3093 | cell_defer(cache, cell, true); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3094 | r = DM_MAPIO_SUBMITTED; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3095 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3096 | } else { |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3097 | inc_miss_counter(cache, bio); |
| 3098 | remap_to_origin_clear_discard(cache, bio, block); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3099 | accounted_begin(cache, bio); |
| 3100 | inc_ds(cache, bio, cell); |
| 3101 | // FIXME: we want to remap hits or misses straight |
| 3102 | // away rather than passing over to the worker. |
| 3103 | cell_defer(cache, cell, false); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3104 | } |
| 3105 | |
| 3106 | } else { |
| 3107 | inc_hit_counter(cache, bio); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3108 | if (bio_data_dir(bio) == WRITE && writethrough_mode(&cache->features) && |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3109 | !is_dirty(cache, lookup_result.cblock)) { |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3110 | remap_to_origin_then_cache(cache, bio, block, lookup_result.cblock); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3111 | accounted_begin(cache, bio); |
| 3112 | inc_ds(cache, bio, cell); |
| 3113 | cell_defer(cache, cell, false); |
| 3114 | |
| 3115 | } else |
| 3116 | remap_cell_to_cache_dirty(cache, cell, block, lookup_result.cblock, false); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3117 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3118 | break; |
| 3119 | |
| 3120 | case POLICY_MISS: |
| 3121 | inc_miss_counter(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3122 | if (pb->req_nr != 0) { |
| 3123 | /* |
| 3124 | * This is a duplicate writethrough io that is no |
| 3125 | * longer needed because the block has been demoted. |
| 3126 | */ |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 3127 | bio_endio(bio); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3128 | // FIXME: remap everything as a miss |
| 3129 | cell_defer(cache, cell, false); |
Joe Thornber | 8c081b5 | 2014-05-13 16:18:38 +0100 | [diff] [blame] | 3130 | r = DM_MAPIO_SUBMITTED; |
| 3131 | |
| 3132 | } else |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3133 | remap_cell_to_origin_clear_discard(cache, cell, block, false); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3134 | break; |
| 3135 | |
| 3136 | default: |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3137 | DMERR_LIMIT("%s: %s: erroring bio: unknown policy op: %u", |
| 3138 | cache_device_name(cache), __func__, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3139 | (unsigned) lookup_result.op); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3140 | cell_defer(cache, cell, false); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3141 | bio_io_error(bio); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3142 | r = DM_MAPIO_SUBMITTED; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3143 | } |
| 3144 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3145 | return r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3146 | } |
| 3147 | |
| 3148 | static int cache_end_io(struct dm_target *ti, struct bio *bio, int error) |
| 3149 | { |
| 3150 | struct cache *cache = ti->private; |
| 3151 | unsigned long flags; |
Mike Snitzer | 19b0092 | 2013-04-05 15:36:34 +0100 | [diff] [blame] | 3152 | size_t pb_data_size = get_per_bio_data_size(cache); |
| 3153 | struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3154 | |
| 3155 | if (pb->tick) { |
Joe Thornber | fba1010 | 2015-05-29 10:20:56 +0100 | [diff] [blame] | 3156 | policy_tick(cache->policy, false); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3157 | |
| 3158 | spin_lock_irqsave(&cache->lock, flags); |
| 3159 | cache->need_tick_bio = true; |
| 3160 | spin_unlock_irqrestore(&cache->lock, flags); |
| 3161 | } |
| 3162 | |
| 3163 | check_for_quiesced_migrations(cache, pb); |
Joe Thornber | 066dbaa | 2015-05-15 15:18:01 +0100 | [diff] [blame] | 3164 | accounted_complete(cache, bio); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3165 | |
| 3166 | return 0; |
| 3167 | } |
| 3168 | |
| 3169 | static int write_dirty_bitset(struct cache *cache) |
| 3170 | { |
| 3171 | unsigned i, r; |
| 3172 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3173 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 3174 | return -EINVAL; |
| 3175 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3176 | for (i = 0; i < from_cblock(cache->cache_size); i++) { |
| 3177 | r = dm_cache_set_dirty(cache->cmd, to_cblock(i), |
| 3178 | is_dirty(cache, to_cblock(i))); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3179 | if (r) { |
| 3180 | metadata_operation_failed(cache, "dm_cache_set_dirty", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3181 | return r; |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3182 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3183 | } |
| 3184 | |
| 3185 | return 0; |
| 3186 | } |
| 3187 | |
| 3188 | static int write_discard_bitset(struct cache *cache) |
| 3189 | { |
| 3190 | unsigned i, r; |
| 3191 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3192 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 3193 | return -EINVAL; |
| 3194 | |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 3195 | r = dm_cache_discard_bitset_resize(cache->cmd, cache->discard_block_size, |
| 3196 | cache->discard_nr_blocks); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3197 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3198 | DMERR("%s: could not resize on-disk discard bitset", cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3199 | metadata_operation_failed(cache, "dm_cache_discard_bitset_resize", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3200 | return r; |
| 3201 | } |
| 3202 | |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 3203 | for (i = 0; i < from_dblock(cache->discard_nr_blocks); i++) { |
| 3204 | r = dm_cache_set_discard(cache->cmd, to_dblock(i), |
| 3205 | is_discarded(cache, to_dblock(i))); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3206 | if (r) { |
| 3207 | metadata_operation_failed(cache, "dm_cache_set_discard", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3208 | return r; |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3209 | } |
| 3210 | } |
| 3211 | |
| 3212 | return 0; |
| 3213 | } |
| 3214 | |
| 3215 | static int write_hints(struct cache *cache) |
| 3216 | { |
| 3217 | int r; |
| 3218 | |
| 3219 | if (get_cache_mode(cache) >= CM_READ_ONLY) |
| 3220 | return -EINVAL; |
| 3221 | |
| 3222 | r = dm_cache_write_hints(cache->cmd, cache->policy); |
| 3223 | if (r) { |
| 3224 | metadata_operation_failed(cache, "dm_cache_write_hints", r); |
| 3225 | return r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3226 | } |
| 3227 | |
| 3228 | return 0; |
| 3229 | } |
| 3230 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3231 | /* |
| 3232 | * returns true on success |
| 3233 | */ |
| 3234 | static bool sync_metadata(struct cache *cache) |
| 3235 | { |
| 3236 | int r1, r2, r3, r4; |
| 3237 | |
| 3238 | r1 = write_dirty_bitset(cache); |
| 3239 | if (r1) |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3240 | DMERR("%s: could not write dirty bitset", cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3241 | |
| 3242 | r2 = write_discard_bitset(cache); |
| 3243 | if (r2) |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3244 | DMERR("%s: could not write discard bitset", cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3245 | |
| 3246 | save_stats(cache); |
| 3247 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3248 | r3 = write_hints(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3249 | if (r3) |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3250 | DMERR("%s: could not write hints", cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3251 | |
| 3252 | /* |
| 3253 | * If writing the above metadata failed, we still commit, but don't |
| 3254 | * set the clean shutdown flag. This will effectively force every |
| 3255 | * dirty bit to be set on reload. |
| 3256 | */ |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3257 | r4 = commit(cache, !r1 && !r2 && !r3); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3258 | if (r4) |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3259 | DMERR("%s: could not write cache metadata", cache_device_name(cache)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3260 | |
| 3261 | return !r1 && !r2 && !r3 && !r4; |
| 3262 | } |
| 3263 | |
| 3264 | static void cache_postsuspend(struct dm_target *ti) |
| 3265 | { |
| 3266 | struct cache *cache = ti->private; |
| 3267 | |
| 3268 | start_quiescing(cache); |
| 3269 | wait_for_migrations(cache); |
| 3270 | stop_worker(cache); |
Joe Thornber | 651f5fa | 2015-05-15 15:26:08 +0100 | [diff] [blame] | 3271 | requeue_deferred_bios(cache); |
| 3272 | requeue_deferred_cells(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3273 | stop_quiescing(cache); |
| 3274 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3275 | if (get_cache_mode(cache) == CM_WRITE) |
| 3276 | (void) sync_metadata(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3277 | } |
| 3278 | |
| 3279 | static int load_mapping(void *context, dm_oblock_t oblock, dm_cblock_t cblock, |
| 3280 | bool dirty, uint32_t hint, bool hint_valid) |
| 3281 | { |
| 3282 | int r; |
| 3283 | struct cache *cache = context; |
| 3284 | |
| 3285 | r = policy_load_mapping(cache->policy, oblock, cblock, hint, hint_valid); |
| 3286 | if (r) |
| 3287 | return r; |
| 3288 | |
| 3289 | if (dirty) |
| 3290 | set_dirty(cache, oblock, cblock); |
| 3291 | else |
| 3292 | clear_dirty(cache, oblock, cblock); |
| 3293 | |
| 3294 | return 0; |
| 3295 | } |
| 3296 | |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3297 | /* |
| 3298 | * The discard block size in the on disk metadata is not |
| 3299 | * neccessarily the same as we're currently using. So we have to |
| 3300 | * be careful to only set the discarded attribute if we know it |
| 3301 | * covers a complete block of the new size. |
| 3302 | */ |
| 3303 | struct discard_load_info { |
| 3304 | struct cache *cache; |
| 3305 | |
| 3306 | /* |
| 3307 | * These blocks are sized using the on disk dblock size, rather |
| 3308 | * than the current one. |
| 3309 | */ |
| 3310 | dm_block_t block_size; |
| 3311 | dm_block_t discard_begin, discard_end; |
| 3312 | }; |
| 3313 | |
| 3314 | static void discard_load_info_init(struct cache *cache, |
| 3315 | struct discard_load_info *li) |
| 3316 | { |
| 3317 | li->cache = cache; |
| 3318 | li->discard_begin = li->discard_end = 0; |
| 3319 | } |
| 3320 | |
| 3321 | static void set_discard_range(struct discard_load_info *li) |
| 3322 | { |
| 3323 | sector_t b, e; |
| 3324 | |
| 3325 | if (li->discard_begin == li->discard_end) |
| 3326 | return; |
| 3327 | |
| 3328 | /* |
| 3329 | * Convert to sectors. |
| 3330 | */ |
| 3331 | b = li->discard_begin * li->block_size; |
| 3332 | e = li->discard_end * li->block_size; |
| 3333 | |
| 3334 | /* |
| 3335 | * Then convert back to the current dblock size. |
| 3336 | */ |
| 3337 | b = dm_sector_div_up(b, li->cache->discard_block_size); |
| 3338 | sector_div(e, li->cache->discard_block_size); |
| 3339 | |
| 3340 | /* |
| 3341 | * The origin may have shrunk, so we need to check we're still in |
| 3342 | * bounds. |
| 3343 | */ |
| 3344 | if (e > from_dblock(li->cache->discard_nr_blocks)) |
| 3345 | e = from_dblock(li->cache->discard_nr_blocks); |
| 3346 | |
| 3347 | for (; b < e; b++) |
| 3348 | set_discard(li->cache, to_dblock(b)); |
| 3349 | } |
| 3350 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3351 | static int load_discard(void *context, sector_t discard_block_size, |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 3352 | dm_dblock_t dblock, bool discard) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3353 | { |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3354 | struct discard_load_info *li = context; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3355 | |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3356 | li->block_size = discard_block_size; |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 3357 | |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3358 | if (discard) { |
| 3359 | if (from_dblock(dblock) == li->discard_end) |
| 3360 | /* |
| 3361 | * We're already in a discard range, just extend it. |
| 3362 | */ |
| 3363 | li->discard_end = li->discard_end + 1ULL; |
| 3364 | |
| 3365 | else { |
| 3366 | /* |
| 3367 | * Emit the old range and start a new one. |
| 3368 | */ |
| 3369 | set_discard_range(li); |
| 3370 | li->discard_begin = from_dblock(dblock); |
| 3371 | li->discard_end = li->discard_begin + 1ULL; |
| 3372 | } |
| 3373 | } else { |
| 3374 | set_discard_range(li); |
| 3375 | li->discard_begin = li->discard_end = 0; |
| 3376 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3377 | |
| 3378 | return 0; |
| 3379 | } |
| 3380 | |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3381 | static dm_cblock_t get_cache_dev_size(struct cache *cache) |
| 3382 | { |
| 3383 | sector_t size = get_dev_size(cache->cache_dev); |
| 3384 | (void) sector_div(size, cache->sectors_per_block); |
| 3385 | return to_cblock(size); |
| 3386 | } |
| 3387 | |
| 3388 | static bool can_resize(struct cache *cache, dm_cblock_t new_size) |
| 3389 | { |
| 3390 | if (from_cblock(new_size) > from_cblock(cache->cache_size)) |
| 3391 | return true; |
| 3392 | |
| 3393 | /* |
| 3394 | * We can't drop a dirty block when shrinking the cache. |
| 3395 | */ |
| 3396 | while (from_cblock(new_size) < from_cblock(cache->cache_size)) { |
| 3397 | new_size = to_cblock(from_cblock(new_size) + 1); |
| 3398 | if (is_dirty(cache, new_size)) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3399 | DMERR("%s: unable to shrink cache; cache block %llu is dirty", |
| 3400 | cache_device_name(cache), |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3401 | (unsigned long long) from_cblock(new_size)); |
| 3402 | return false; |
| 3403 | } |
| 3404 | } |
| 3405 | |
| 3406 | return true; |
| 3407 | } |
| 3408 | |
| 3409 | static int resize_cache_dev(struct cache *cache, dm_cblock_t new_size) |
| 3410 | { |
| 3411 | int r; |
| 3412 | |
Vincent Pelletier | 0884480 | 2013-11-30 12:58:42 +0100 | [diff] [blame] | 3413 | r = dm_cache_resize(cache->cmd, new_size); |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3414 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3415 | DMERR("%s: could not resize cache metadata", cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3416 | metadata_operation_failed(cache, "dm_cache_resize", r); |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3417 | return r; |
| 3418 | } |
| 3419 | |
Joe Thornber | d1d9220 | 2014-11-11 11:58:32 +0000 | [diff] [blame] | 3420 | set_cache_size(cache, new_size); |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3421 | |
| 3422 | return 0; |
| 3423 | } |
| 3424 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3425 | static int cache_preresume(struct dm_target *ti) |
| 3426 | { |
| 3427 | int r = 0; |
| 3428 | struct cache *cache = ti->private; |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3429 | dm_cblock_t csize = get_cache_dev_size(cache); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3430 | |
| 3431 | /* |
| 3432 | * Check to see if the cache has resized. |
| 3433 | */ |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3434 | if (!cache->sized) { |
| 3435 | r = resize_cache_dev(cache, csize); |
| 3436 | if (r) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3437 | return r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3438 | |
| 3439 | cache->sized = true; |
Joe Thornber | f494a9c | 2013-10-31 13:55:49 -0400 | [diff] [blame] | 3440 | |
| 3441 | } else if (csize != cache->cache_size) { |
| 3442 | if (!can_resize(cache, csize)) |
| 3443 | return -EINVAL; |
| 3444 | |
| 3445 | r = resize_cache_dev(cache, csize); |
| 3446 | if (r) |
| 3447 | return r; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3448 | } |
| 3449 | |
| 3450 | if (!cache->loaded_mappings) { |
Mike Snitzer | ea2dd8c | 2013-03-20 17:21:28 +0000 | [diff] [blame] | 3451 | r = dm_cache_load_mappings(cache->cmd, cache->policy, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3452 | load_mapping, cache); |
| 3453 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3454 | DMERR("%s: could not load cache mappings", cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3455 | metadata_operation_failed(cache, "dm_cache_load_mappings", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3456 | return r; |
| 3457 | } |
| 3458 | |
| 3459 | cache->loaded_mappings = true; |
| 3460 | } |
| 3461 | |
| 3462 | if (!cache->loaded_discards) { |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3463 | struct discard_load_info li; |
| 3464 | |
| 3465 | /* |
| 3466 | * The discard bitset could have been resized, or the |
| 3467 | * discard block size changed. To be safe we start by |
| 3468 | * setting every dblock to not discarded. |
| 3469 | */ |
| 3470 | clear_bitset(cache->discard_bitset, from_dblock(cache->discard_nr_blocks)); |
| 3471 | |
| 3472 | discard_load_info_init(cache, &li); |
| 3473 | r = dm_cache_load_discards(cache->cmd, load_discard, &li); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3474 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3475 | DMERR("%s: could not load origin discards", cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3476 | metadata_operation_failed(cache, "dm_cache_load_discards", r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3477 | return r; |
| 3478 | } |
Joe Thornber | 3e2e1c3 | 2014-11-24 14:06:22 +0000 | [diff] [blame] | 3479 | set_discard_range(&li); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3480 | |
| 3481 | cache->loaded_discards = true; |
| 3482 | } |
| 3483 | |
| 3484 | return r; |
| 3485 | } |
| 3486 | |
| 3487 | static void cache_resume(struct dm_target *ti) |
| 3488 | { |
| 3489 | struct cache *cache = ti->private; |
| 3490 | |
| 3491 | cache->need_tick_bio = true; |
| 3492 | do_waker(&cache->waker.work); |
| 3493 | } |
| 3494 | |
| 3495 | /* |
| 3496 | * Status format: |
| 3497 | * |
Mike Snitzer | 6a38861 | 2014-01-09 16:04:12 -0500 | [diff] [blame] | 3498 | * <metadata block size> <#used metadata blocks>/<#total metadata blocks> |
| 3499 | * <cache block size> <#used cache blocks>/<#total cache blocks> |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3500 | * <#read hits> <#read misses> <#write hits> <#write misses> |
Mike Snitzer | 6a38861 | 2014-01-09 16:04:12 -0500 | [diff] [blame] | 3501 | * <#demotions> <#promotions> <#dirty> |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3502 | * <#features> <features>* |
| 3503 | * <#core args> <core args> |
Mike Snitzer | 255eac2 | 2015-07-15 11:42:59 -0400 | [diff] [blame] | 3504 | * <policy name> <#policy args> <policy args>* <cache metadata mode> <needs_check> |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3505 | */ |
| 3506 | static void cache_status(struct dm_target *ti, status_type_t type, |
| 3507 | unsigned status_flags, char *result, unsigned maxlen) |
| 3508 | { |
| 3509 | int r = 0; |
| 3510 | unsigned i; |
| 3511 | ssize_t sz = 0; |
| 3512 | dm_block_t nr_free_blocks_metadata = 0; |
| 3513 | dm_block_t nr_blocks_metadata = 0; |
| 3514 | char buf[BDEVNAME_SIZE]; |
| 3515 | struct cache *cache = ti->private; |
| 3516 | dm_cblock_t residency; |
| 3517 | |
| 3518 | switch (type) { |
| 3519 | case STATUSTYPE_INFO: |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3520 | if (get_cache_mode(cache) == CM_FAIL) { |
| 3521 | DMEMIT("Fail"); |
| 3522 | break; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3523 | } |
| 3524 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3525 | /* Commit to ensure statistics aren't out-of-date */ |
| 3526 | if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti)) |
| 3527 | (void) commit(cache, false); |
| 3528 | |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3529 | r = dm_cache_get_free_metadata_block_count(cache->cmd, &nr_free_blocks_metadata); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3530 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3531 | DMERR("%s: dm_cache_get_free_metadata_block_count returned %d", |
| 3532 | cache_device_name(cache), r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3533 | goto err; |
| 3534 | } |
| 3535 | |
| 3536 | r = dm_cache_get_metadata_dev_size(cache->cmd, &nr_blocks_metadata); |
| 3537 | if (r) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3538 | DMERR("%s: dm_cache_get_metadata_dev_size returned %d", |
| 3539 | cache_device_name(cache), r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3540 | goto err; |
| 3541 | } |
| 3542 | |
| 3543 | residency = policy_residency(cache->policy); |
| 3544 | |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 3545 | DMEMIT("%u %llu/%llu %u %llu/%llu %u %u %u %u %u %u %lu ", |
Mike Snitzer | 895b47d | 2014-07-14 15:37:18 -0400 | [diff] [blame] | 3546 | (unsigned)DM_CACHE_METADATA_BLOCK_SIZE, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3547 | (unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata), |
| 3548 | (unsigned long long)nr_blocks_metadata, |
Mike Snitzer | 6a38861 | 2014-01-09 16:04:12 -0500 | [diff] [blame] | 3549 | cache->sectors_per_block, |
| 3550 | (unsigned long long) from_cblock(residency), |
| 3551 | (unsigned long long) from_cblock(cache->cache_size), |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3552 | (unsigned) atomic_read(&cache->stats.read_hit), |
| 3553 | (unsigned) atomic_read(&cache->stats.read_miss), |
| 3554 | (unsigned) atomic_read(&cache->stats.write_hit), |
| 3555 | (unsigned) atomic_read(&cache->stats.write_miss), |
| 3556 | (unsigned) atomic_read(&cache->stats.demotion), |
| 3557 | (unsigned) atomic_read(&cache->stats.promotion), |
Anssi Hannula | 44fa816 | 2014-08-01 11:55:47 -0400 | [diff] [blame] | 3558 | (unsigned long) atomic_read(&cache->nr_dirty)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3559 | |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3560 | if (writethrough_mode(&cache->features)) |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3561 | DMEMIT("1 writethrough "); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3562 | |
| 3563 | else if (passthrough_mode(&cache->features)) |
| 3564 | DMEMIT("1 passthrough "); |
| 3565 | |
| 3566 | else if (writeback_mode(&cache->features)) |
| 3567 | DMEMIT("1 writeback "); |
| 3568 | |
| 3569 | else { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3570 | DMERR("%s: internal error: unknown io mode: %d", |
| 3571 | cache_device_name(cache), (int) cache->features.io_mode); |
Joe Thornber | 2ee57d5 | 2013-10-24 14:10:29 -0400 | [diff] [blame] | 3572 | goto err; |
| 3573 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3574 | |
| 3575 | DMEMIT("2 migration_threshold %llu ", (unsigned long long) cache->migration_threshold); |
Mike Snitzer | 2e68c4e | 2014-01-15 21:06:55 -0500 | [diff] [blame] | 3576 | |
| 3577 | DMEMIT("%s ", dm_cache_policy_get_name(cache->policy)); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3578 | if (sz < maxlen) { |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3579 | r = policy_emit_config_values(cache->policy, result, maxlen, &sz); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3580 | if (r) |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3581 | DMERR("%s: policy_emit_config_values returned %d", |
| 3582 | cache_device_name(cache), r); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3583 | } |
| 3584 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3585 | if (get_cache_mode(cache) == CM_READ_ONLY) |
| 3586 | DMEMIT("ro "); |
| 3587 | else |
| 3588 | DMEMIT("rw "); |
| 3589 | |
Mike Snitzer | 255eac2 | 2015-07-15 11:42:59 -0400 | [diff] [blame] | 3590 | if (dm_cache_metadata_needs_check(cache->cmd)) |
| 3591 | DMEMIT("needs_check "); |
| 3592 | else |
| 3593 | DMEMIT("- "); |
| 3594 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3595 | break; |
| 3596 | |
| 3597 | case STATUSTYPE_TABLE: |
| 3598 | format_dev_t(buf, cache->metadata_dev->bdev->bd_dev); |
| 3599 | DMEMIT("%s ", buf); |
| 3600 | format_dev_t(buf, cache->cache_dev->bdev->bd_dev); |
| 3601 | DMEMIT("%s ", buf); |
| 3602 | format_dev_t(buf, cache->origin_dev->bdev->bd_dev); |
| 3603 | DMEMIT("%s", buf); |
| 3604 | |
| 3605 | for (i = 0; i < cache->nr_ctr_args - 1; i++) |
| 3606 | DMEMIT(" %s", cache->ctr_args[i]); |
| 3607 | if (cache->nr_ctr_args) |
| 3608 | DMEMIT(" %s", cache->ctr_args[cache->nr_ctr_args - 1]); |
| 3609 | } |
| 3610 | |
| 3611 | return; |
| 3612 | |
| 3613 | err: |
| 3614 | DMEMIT("Error"); |
| 3615 | } |
| 3616 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3617 | /* |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3618 | * A cache block range can take two forms: |
| 3619 | * |
| 3620 | * i) A single cblock, eg. '3456' |
| 3621 | * ii) A begin and end cblock with dots between, eg. 123-234 |
| 3622 | */ |
| 3623 | static int parse_cblock_range(struct cache *cache, const char *str, |
| 3624 | struct cblock_range *result) |
| 3625 | { |
| 3626 | char dummy; |
| 3627 | uint64_t b, e; |
| 3628 | int r; |
| 3629 | |
| 3630 | /* |
| 3631 | * Try and parse form (ii) first. |
| 3632 | */ |
| 3633 | r = sscanf(str, "%llu-%llu%c", &b, &e, &dummy); |
| 3634 | if (r < 0) |
| 3635 | return r; |
| 3636 | |
| 3637 | if (r == 2) { |
| 3638 | result->begin = to_cblock(b); |
| 3639 | result->end = to_cblock(e); |
| 3640 | return 0; |
| 3641 | } |
| 3642 | |
| 3643 | /* |
| 3644 | * That didn't work, try form (i). |
| 3645 | */ |
| 3646 | r = sscanf(str, "%llu%c", &b, &dummy); |
| 3647 | if (r < 0) |
| 3648 | return r; |
| 3649 | |
| 3650 | if (r == 1) { |
| 3651 | result->begin = to_cblock(b); |
| 3652 | result->end = to_cblock(from_cblock(result->begin) + 1u); |
| 3653 | return 0; |
| 3654 | } |
| 3655 | |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3656 | DMERR("%s: invalid cblock range '%s'", cache_device_name(cache), str); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3657 | return -EINVAL; |
| 3658 | } |
| 3659 | |
| 3660 | static int validate_cblock_range(struct cache *cache, struct cblock_range *range) |
| 3661 | { |
| 3662 | uint64_t b = from_cblock(range->begin); |
| 3663 | uint64_t e = from_cblock(range->end); |
| 3664 | uint64_t n = from_cblock(cache->cache_size); |
| 3665 | |
| 3666 | if (b >= n) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3667 | DMERR("%s: begin cblock out of range: %llu >= %llu", |
| 3668 | cache_device_name(cache), b, n); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3669 | return -EINVAL; |
| 3670 | } |
| 3671 | |
| 3672 | if (e > n) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3673 | DMERR("%s: end cblock out of range: %llu > %llu", |
| 3674 | cache_device_name(cache), e, n); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3675 | return -EINVAL; |
| 3676 | } |
| 3677 | |
| 3678 | if (b >= e) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3679 | DMERR("%s: invalid cblock range: %llu >= %llu", |
| 3680 | cache_device_name(cache), b, e); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3681 | return -EINVAL; |
| 3682 | } |
| 3683 | |
| 3684 | return 0; |
| 3685 | } |
| 3686 | |
| 3687 | static int request_invalidation(struct cache *cache, struct cblock_range *range) |
| 3688 | { |
| 3689 | struct invalidation_request req; |
| 3690 | |
| 3691 | INIT_LIST_HEAD(&req.list); |
| 3692 | req.cblocks = range; |
| 3693 | atomic_set(&req.complete, 0); |
| 3694 | req.err = 0; |
| 3695 | init_waitqueue_head(&req.result_wait); |
| 3696 | |
| 3697 | spin_lock(&cache->invalidation_lock); |
| 3698 | list_add(&req.list, &cache->invalidation_requests); |
| 3699 | spin_unlock(&cache->invalidation_lock); |
| 3700 | wake_worker(cache); |
| 3701 | |
| 3702 | wait_event(req.result_wait, atomic_read(&req.complete)); |
| 3703 | return req.err; |
| 3704 | } |
| 3705 | |
| 3706 | static int process_invalidate_cblocks_message(struct cache *cache, unsigned count, |
| 3707 | const char **cblock_ranges) |
| 3708 | { |
| 3709 | int r = 0; |
| 3710 | unsigned i; |
| 3711 | struct cblock_range range; |
| 3712 | |
| 3713 | if (!passthrough_mode(&cache->features)) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3714 | DMERR("%s: cache has to be in passthrough mode for invalidation", |
| 3715 | cache_device_name(cache)); |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3716 | return -EPERM; |
| 3717 | } |
| 3718 | |
| 3719 | for (i = 0; i < count; i++) { |
| 3720 | r = parse_cblock_range(cache, cblock_ranges[i], &range); |
| 3721 | if (r) |
| 3722 | break; |
| 3723 | |
| 3724 | r = validate_cblock_range(cache, &range); |
| 3725 | if (r) |
| 3726 | break; |
| 3727 | |
| 3728 | /* |
| 3729 | * Pass begin and end origin blocks to the worker and wake it. |
| 3730 | */ |
| 3731 | r = request_invalidation(cache, &range); |
| 3732 | if (r) |
| 3733 | break; |
| 3734 | } |
| 3735 | |
| 3736 | return r; |
| 3737 | } |
| 3738 | |
| 3739 | /* |
| 3740 | * Supports |
| 3741 | * "<key> <value>" |
| 3742 | * and |
| 3743 | * "invalidate_cblocks [(<begin>)|(<begin>-<end>)]* |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3744 | * |
| 3745 | * The key migration_threshold is supported by the cache target core. |
| 3746 | */ |
| 3747 | static int cache_message(struct dm_target *ti, unsigned argc, char **argv) |
| 3748 | { |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3749 | struct cache *cache = ti->private; |
| 3750 | |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3751 | if (!argc) |
| 3752 | return -EINVAL; |
| 3753 | |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3754 | if (get_cache_mode(cache) >= CM_READ_ONLY) { |
Mike Snitzer | b61d950 | 2015-04-22 17:25:56 -0400 | [diff] [blame] | 3755 | DMERR("%s: unable to service cache target messages in READ_ONLY or FAIL mode", |
| 3756 | cache_device_name(cache)); |
Joe Thornber | 028ae9f | 2015-04-22 16:42:35 -0400 | [diff] [blame] | 3757 | return -EOPNOTSUPP; |
| 3758 | } |
| 3759 | |
Mike Snitzer | 7b6b2bc | 2013-11-12 12:17:43 -0500 | [diff] [blame] | 3760 | if (!strcasecmp(argv[0], "invalidate_cblocks")) |
Joe Thornber | 65790ff | 2013-11-08 16:39:50 +0000 | [diff] [blame] | 3761 | return process_invalidate_cblocks_message(cache, argc - 1, (const char **) argv + 1); |
| 3762 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3763 | if (argc != 2) |
| 3764 | return -EINVAL; |
| 3765 | |
Joe Thornber | 2f14f4b | 2013-05-10 14:37:21 +0100 | [diff] [blame] | 3766 | return set_config_value(cache, argv[0], argv[1]); |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3767 | } |
| 3768 | |
| 3769 | static int cache_iterate_devices(struct dm_target *ti, |
| 3770 | iterate_devices_callout_fn fn, void *data) |
| 3771 | { |
| 3772 | int r = 0; |
| 3773 | struct cache *cache = ti->private; |
| 3774 | |
| 3775 | r = fn(ti, cache->cache_dev, 0, get_dev_size(cache->cache_dev), data); |
| 3776 | if (!r) |
| 3777 | r = fn(ti, cache->origin_dev, 0, ti->len, data); |
| 3778 | |
| 3779 | return r; |
| 3780 | } |
| 3781 | |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3782 | static void set_discard_limits(struct cache *cache, struct queue_limits *limits) |
| 3783 | { |
| 3784 | /* |
| 3785 | * FIXME: these limits may be incompatible with the cache device |
| 3786 | */ |
Joe Thornber | 7ae34e7 | 2014-11-06 10:18:04 +0000 | [diff] [blame] | 3787 | limits->max_discard_sectors = min_t(sector_t, cache->discard_block_size * 1024, |
| 3788 | cache->origin_sectors); |
Joe Thornber | 1bad9bc | 2014-11-07 14:47:07 +0000 | [diff] [blame] | 3789 | limits->discard_granularity = cache->discard_block_size << SECTOR_SHIFT; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3790 | } |
| 3791 | |
| 3792 | static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) |
| 3793 | { |
| 3794 | struct cache *cache = ti->private; |
Mike Snitzer | f610937 | 2013-08-20 15:02:41 -0400 | [diff] [blame] | 3795 | uint64_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT; |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3796 | |
Mike Snitzer | f610937 | 2013-08-20 15:02:41 -0400 | [diff] [blame] | 3797 | /* |
| 3798 | * If the system-determined stacked limits are compatible with the |
| 3799 | * cache's blocksize (io_opt is a factor) do not override them. |
| 3800 | */ |
| 3801 | if (io_opt_sectors < cache->sectors_per_block || |
| 3802 | do_div(io_opt_sectors, cache->sectors_per_block)) { |
Mike Snitzer | b024653 | 2014-07-19 13:25:46 -0400 | [diff] [blame] | 3803 | blk_limits_io_min(limits, cache->sectors_per_block << SECTOR_SHIFT); |
Mike Snitzer | f610937 | 2013-08-20 15:02:41 -0400 | [diff] [blame] | 3804 | blk_limits_io_opt(limits, cache->sectors_per_block << SECTOR_SHIFT); |
| 3805 | } |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3806 | set_discard_limits(cache, limits); |
| 3807 | } |
| 3808 | |
| 3809 | /*----------------------------------------------------------------*/ |
| 3810 | |
| 3811 | static struct target_type cache_target = { |
| 3812 | .name = "cache", |
Mike Snitzer | 255eac2 | 2015-07-15 11:42:59 -0400 | [diff] [blame] | 3813 | .version = {1, 8, 0}, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3814 | .module = THIS_MODULE, |
| 3815 | .ctr = cache_ctr, |
| 3816 | .dtr = cache_dtr, |
| 3817 | .map = cache_map, |
| 3818 | .end_io = cache_end_io, |
| 3819 | .postsuspend = cache_postsuspend, |
| 3820 | .preresume = cache_preresume, |
| 3821 | .resume = cache_resume, |
| 3822 | .status = cache_status, |
| 3823 | .message = cache_message, |
| 3824 | .iterate_devices = cache_iterate_devices, |
Joe Thornber | c6b4fcb | 2013-03-01 22:45:51 +0000 | [diff] [blame] | 3825 | .io_hints = cache_io_hints, |
| 3826 | }; |
| 3827 | |
| 3828 | static int __init dm_cache_init(void) |
| 3829 | { |
| 3830 | int r; |
| 3831 | |
| 3832 | r = dm_register_target(&cache_target); |
| 3833 | if (r) { |
| 3834 | DMERR("cache target registration failed: %d", r); |
| 3835 | return r; |
| 3836 | } |
| 3837 | |
| 3838 | migration_cache = KMEM_CACHE(dm_cache_migration, 0); |
| 3839 | if (!migration_cache) { |
| 3840 | dm_unregister_target(&cache_target); |
| 3841 | return -ENOMEM; |
| 3842 | } |
| 3843 | |
| 3844 | return 0; |
| 3845 | } |
| 3846 | |
| 3847 | static void __exit dm_cache_exit(void) |
| 3848 | { |
| 3849 | dm_unregister_target(&cache_target); |
| 3850 | kmem_cache_destroy(migration_cache); |
| 3851 | } |
| 3852 | |
| 3853 | module_init(dm_cache_init); |
| 3854 | module_exit(dm_cache_exit); |
| 3855 | |
| 3856 | MODULE_DESCRIPTION(DM_NAME " cache target"); |
| 3857 | MODULE_AUTHOR("Joe Thornber <ejt@redhat.com>"); |
| 3858 | MODULE_LICENSE("GPL"); |