1 /* 2 * Copyright (C) 2007 Oracle. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public 6 * License v2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public 14 * License along with this program; if not, write to the 15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330, 16 * Boston, MA 021110-1307, USA. 17 */ 18 19 #ifndef __BTRFS_VOLUMES_ 20 #define __BTRFS_VOLUMES_ 21 22 #include <linux/bio.h> 23 #include <linux/sort.h> 24 #include <linux/btrfs.h> 25 #include "async-thread.h" 26 27 extern struct mutex uuid_mutex; 28 29 #define BTRFS_STRIPE_LEN SZ_64K 30 31 struct buffer_head; 32 struct btrfs_pending_bios { 33 struct bio *head; 34 struct bio *tail; 35 }; 36 37 /* 38 * Use sequence counter to get consistent device stat data on 39 * 32-bit processors. 40 */ 41 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 42 #include <linux/seqlock.h> 43 #define __BTRFS_NEED_DEVICE_DATA_ORDERED 44 #define btrfs_device_data_ordered_init(device) \ 45 seqcount_init(&device->data_seqcount) 46 #else 47 #define btrfs_device_data_ordered_init(device) do { } while (0) 48 #endif 49 50 #define BTRFS_DEV_STATE_WRITEABLE (0) 51 #define BTRFS_DEV_STATE_IN_FS_METADATA (1) 52 #define BTRFS_DEV_STATE_MISSING (2) 53 #define BTRFS_DEV_STATE_REPLACE_TGT (3) 54 #define BTRFS_DEV_STATE_FLUSH_SENT (4) 55 56 struct btrfs_device { 57 struct list_head dev_list; 58 struct list_head dev_alloc_list; 59 struct btrfs_fs_devices *fs_devices; 60 struct btrfs_fs_info *fs_info; 61 62 struct rcu_string *name; 63 64 u64 generation; 65 66 spinlock_t io_lock ____cacheline_aligned; 67 int running_pending; 68 /* regular prio bios */ 69 struct btrfs_pending_bios pending_bios; 70 /* sync bios */ 71 struct btrfs_pending_bios pending_sync_bios; 72 73 struct block_device *bdev; 74 75 /* the mode sent to blkdev_get */ 76 fmode_t mode; 77 78 unsigned long dev_state; 79 blk_status_t last_flush_error; 80 int flush_bio_sent; 81 82 #ifdef __BTRFS_NEED_DEVICE_DATA_ORDERED 83 seqcount_t data_seqcount; 84 #endif 85 86 /* the internal btrfs device id */ 87 u64 devid; 88 89 /* size of the device in memory */ 90 u64 total_bytes; 91 92 /* size of the device on disk */ 93 u64 disk_total_bytes; 94 95 /* bytes used */ 96 u64 bytes_used; 97 98 /* optimal io alignment for this device */ 99 u32 io_align; 100 101 /* optimal io width for this device */ 102 u32 io_width; 103 /* type and info about this device */ 104 u64 type; 105 106 /* minimal io size for this device */ 107 u32 sector_size; 108 109 /* physical drive uuid (or lvm uuid) */ 110 u8 uuid[BTRFS_UUID_SIZE]; 111 112 /* 113 * size of the device on the current transaction 114 * 115 * This variant is update when committing the transaction, 116 * and protected by device_list_mutex 117 */ 118 u64 commit_total_bytes; 119 120 /* bytes used on the current transaction */ 121 u64 commit_bytes_used; 122 /* 123 * used to manage the device which is resized 124 * 125 * It is protected by chunk_lock. 126 */ 127 struct list_head resized_list; 128 129 /* for sending down flush barriers */ 130 struct bio *flush_bio; 131 struct completion flush_wait; 132 133 /* per-device scrub information */ 134 struct scrub_ctx *scrub_ctx; 135 136 struct btrfs_work work; 137 struct rcu_head rcu; 138 139 /* readahead state */ 140 atomic_t reada_in_flight; 141 u64 reada_next; 142 struct reada_zone *reada_curr_zone; 143 struct radix_tree_root reada_zones; 144 struct radix_tree_root reada_extents; 145 146 /* disk I/O failure stats. For detailed description refer to 147 * enum btrfs_dev_stat_values in ioctl.h */ 148 int dev_stats_valid; 149 150 /* Counter to record the change of device stats */ 151 atomic_t dev_stats_ccnt; 152 atomic_t dev_stat_values[BTRFS_DEV_STAT_VALUES_MAX]; 153 }; 154 155 /* 156 * If we read those variants at the context of their own lock, we needn't 157 * use the following helpers, reading them directly is safe. 158 */ 159 #if BITS_PER_LONG==32 && defined(CONFIG_SMP) 160 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 161 static inline u64 \ 162 btrfs_device_get_##name(const struct btrfs_device *dev) \ 163 { \ 164 u64 size; \ 165 unsigned int seq; \ 166 \ 167 do { \ 168 seq = read_seqcount_begin(&dev->data_seqcount); \ 169 size = dev->name; \ 170 } while (read_seqcount_retry(&dev->data_seqcount, seq)); \ 171 return size; \ 172 } \ 173 \ 174 static inline void \ 175 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 176 { \ 177 preempt_disable(); \ 178 write_seqcount_begin(&dev->data_seqcount); \ 179 dev->name = size; \ 180 write_seqcount_end(&dev->data_seqcount); \ 181 preempt_enable(); \ 182 } 183 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT) 184 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 185 static inline u64 \ 186 btrfs_device_get_##name(const struct btrfs_device *dev) \ 187 { \ 188 u64 size; \ 189 \ 190 preempt_disable(); \ 191 size = dev->name; \ 192 preempt_enable(); \ 193 return size; \ 194 } \ 195 \ 196 static inline void \ 197 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 198 { \ 199 preempt_disable(); \ 200 dev->name = size; \ 201 preempt_enable(); \ 202 } 203 #else 204 #define BTRFS_DEVICE_GETSET_FUNCS(name) \ 205 static inline u64 \ 206 btrfs_device_get_##name(const struct btrfs_device *dev) \ 207 { \ 208 return dev->name; \ 209 } \ 210 \ 211 static inline void \ 212 btrfs_device_set_##name(struct btrfs_device *dev, u64 size) \ 213 { \ 214 dev->name = size; \ 215 } 216 #endif 217 218 BTRFS_DEVICE_GETSET_FUNCS(total_bytes); 219 BTRFS_DEVICE_GETSET_FUNCS(disk_total_bytes); 220 BTRFS_DEVICE_GETSET_FUNCS(bytes_used); 221 222 struct btrfs_fs_devices { 223 u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */ 224 225 u64 num_devices; 226 u64 open_devices; 227 u64 rw_devices; 228 u64 missing_devices; 229 u64 total_rw_bytes; 230 u64 total_devices; 231 struct block_device *latest_bdev; 232 233 /* all of the devices in the FS, protected by a mutex 234 * so we can safely walk it to write out the supers without 235 * worrying about add/remove by the multi-device code. 236 * Scrubbing super can kick off supers writing by holding 237 * this mutex lock. 238 */ 239 struct mutex device_list_mutex; 240 struct list_head devices; 241 242 struct list_head resized_devices; 243 /* devices not currently being allocated */ 244 struct list_head alloc_list; 245 struct list_head list; 246 247 struct btrfs_fs_devices *seed; 248 int seeding; 249 250 int opened; 251 252 /* set when we find or add a device that doesn't have the 253 * nonrot flag set 254 */ 255 int rotating; 256 257 struct btrfs_fs_info *fs_info; 258 /* sysfs kobjects */ 259 struct kobject fsid_kobj; 260 struct kobject *device_dir_kobj; 261 struct completion kobj_unregister; 262 }; 263 264 #define BTRFS_BIO_INLINE_CSUM_SIZE 64 265 266 /* 267 * we need the mirror number and stripe index to be passed around 268 * the call chain while we are processing end_io (especially errors). 269 * Really, what we need is a btrfs_bio structure that has this info 270 * and is properly sized with its stripe array, but we're not there 271 * quite yet. We have our own btrfs bioset, and all of the bios 272 * we allocate are actually btrfs_io_bios. We'll cram as much of 273 * struct btrfs_bio as we can into this over time. 274 */ 275 typedef void (btrfs_io_bio_end_io_t) (struct btrfs_io_bio *bio, int err); 276 struct btrfs_io_bio { 277 unsigned int mirror_num; 278 unsigned int stripe_index; 279 u64 logical; 280 u8 *csum; 281 u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE]; 282 u8 *csum_allocated; 283 btrfs_io_bio_end_io_t *end_io; 284 struct bvec_iter iter; 285 /* 286 * This member must come last, bio_alloc_bioset will allocate enough 287 * bytes for entire btrfs_io_bio but relies on bio being last. 288 */ 289 struct bio bio; 290 }; 291 292 static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio) 293 { 294 return container_of(bio, struct btrfs_io_bio, bio); 295 } 296 297 struct btrfs_bio_stripe { 298 struct btrfs_device *dev; 299 u64 physical; 300 u64 length; /* only used for discard mappings */ 301 }; 302 303 struct btrfs_bio; 304 typedef void (btrfs_bio_end_io_t) (struct btrfs_bio *bio, int err); 305 306 struct btrfs_bio { 307 refcount_t refs; 308 atomic_t stripes_pending; 309 struct btrfs_fs_info *fs_info; 310 u64 map_type; /* get from map_lookup->type */ 311 bio_end_io_t *end_io; 312 struct bio *orig_bio; 313 unsigned long flags; 314 void *private; 315 atomic_t error; 316 int max_errors; 317 int num_stripes; 318 int mirror_num; 319 int num_tgtdevs; 320 int *tgtdev_map; 321 /* 322 * logical block numbers for the start of each stripe 323 * The last one or two are p/q. These are sorted, 324 * so raid_map[0] is the start of our full stripe 325 */ 326 u64 *raid_map; 327 struct btrfs_bio_stripe stripes[]; 328 }; 329 330 struct btrfs_device_info { 331 struct btrfs_device *dev; 332 u64 dev_offset; 333 u64 max_avail; 334 u64 total_avail; 335 }; 336 337 struct btrfs_raid_attr { 338 int sub_stripes; /* sub_stripes info for map */ 339 int dev_stripes; /* stripes per dev */ 340 int devs_max; /* max devs to use */ 341 int devs_min; /* min devs needed */ 342 int tolerated_failures; /* max tolerated fail devs */ 343 int devs_increment; /* ndevs has to be a multiple of this */ 344 int ncopies; /* how many copies to data has */ 345 }; 346 347 extern const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES]; 348 extern const int btrfs_raid_mindev_error[BTRFS_NR_RAID_TYPES]; 349 extern const u64 btrfs_raid_group[BTRFS_NR_RAID_TYPES]; 350 351 struct map_lookup { 352 u64 type; 353 int io_align; 354 int io_width; 355 u64 stripe_len; 356 int num_stripes; 357 int sub_stripes; 358 struct btrfs_bio_stripe stripes[]; 359 }; 360 361 #define map_lookup_size(n) (sizeof(struct map_lookup) + \ 362 (sizeof(struct btrfs_bio_stripe) * (n))) 363 364 struct btrfs_balance_args; 365 struct btrfs_balance_progress; 366 struct btrfs_balance_control { 367 struct btrfs_fs_info *fs_info; 368 369 struct btrfs_balance_args data; 370 struct btrfs_balance_args meta; 371 struct btrfs_balance_args sys; 372 373 u64 flags; 374 375 struct btrfs_balance_progress stat; 376 }; 377 378 enum btrfs_map_op { 379 BTRFS_MAP_READ, 380 BTRFS_MAP_WRITE, 381 BTRFS_MAP_DISCARD, 382 BTRFS_MAP_GET_READ_MIRRORS, 383 }; 384 385 static inline enum btrfs_map_op btrfs_op(struct bio *bio) 386 { 387 switch (bio_op(bio)) { 388 case REQ_OP_DISCARD: 389 return BTRFS_MAP_DISCARD; 390 case REQ_OP_WRITE: 391 return BTRFS_MAP_WRITE; 392 default: 393 WARN_ON_ONCE(1); 394 case REQ_OP_READ: 395 return BTRFS_MAP_READ; 396 } 397 } 398 399 int btrfs_account_dev_extents_size(struct btrfs_device *device, u64 start, 400 u64 end, u64 *length); 401 void btrfs_get_bbio(struct btrfs_bio *bbio); 402 void btrfs_put_bbio(struct btrfs_bio *bbio); 403 int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 404 u64 logical, u64 *length, 405 struct btrfs_bio **bbio_ret, int mirror_num); 406 int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, 407 u64 logical, u64 *length, 408 struct btrfs_bio **bbio_ret); 409 int btrfs_rmap_block(struct btrfs_fs_info *fs_info, 410 u64 chunk_start, u64 physical, u64 devid, 411 u64 **logical, int *naddrs, int *stripe_len); 412 int btrfs_read_sys_array(struct btrfs_fs_info *fs_info); 413 int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info); 414 int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, 415 struct btrfs_fs_info *fs_info, u64 type); 416 void btrfs_mapping_init(struct btrfs_mapping_tree *tree); 417 void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree); 418 blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio, 419 int mirror_num, int async_submit); 420 int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, 421 fmode_t flags, void *holder); 422 int btrfs_scan_one_device(const char *path, fmode_t flags, void *holder, 423 struct btrfs_fs_devices **fs_devices_ret); 424 int btrfs_close_devices(struct btrfs_fs_devices *fs_devices); 425 void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices, int step); 426 void btrfs_assign_next_active_device(struct btrfs_fs_info *fs_info, 427 struct btrfs_device *device, struct btrfs_device *this_dev); 428 int btrfs_find_device_missing_or_by_path(struct btrfs_fs_info *fs_info, 429 const char *device_path, 430 struct btrfs_device **device); 431 int btrfs_find_device_by_devspec(struct btrfs_fs_info *fs_info, u64 devid, 432 const char *devpath, 433 struct btrfs_device **device); 434 struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info, 435 const u64 *devid, 436 const u8 *uuid); 437 int btrfs_rm_device(struct btrfs_fs_info *fs_info, 438 const char *device_path, u64 devid); 439 void btrfs_cleanup_fs_uuids(void); 440 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len); 441 int btrfs_grow_device(struct btrfs_trans_handle *trans, 442 struct btrfs_device *device, u64 new_size); 443 struct btrfs_device *btrfs_find_device(struct btrfs_fs_info *fs_info, u64 devid, 444 u8 *uuid, u8 *fsid); 445 int btrfs_shrink_device(struct btrfs_device *device, u64 new_size); 446 int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *path); 447 int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 448 const char *device_path, 449 struct btrfs_device *srcdev, 450 struct btrfs_device **device_out); 451 int btrfs_balance(struct btrfs_balance_control *bctl, 452 struct btrfs_ioctl_balance_args *bargs); 453 int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info); 454 int btrfs_recover_balance(struct btrfs_fs_info *fs_info); 455 int btrfs_pause_balance(struct btrfs_fs_info *fs_info); 456 int btrfs_cancel_balance(struct btrfs_fs_info *fs_info); 457 int btrfs_create_uuid_tree(struct btrfs_fs_info *fs_info); 458 int btrfs_check_uuid_tree(struct btrfs_fs_info *fs_info); 459 int btrfs_chunk_readonly(struct btrfs_fs_info *fs_info, u64 chunk_offset); 460 int find_free_dev_extent_start(struct btrfs_transaction *transaction, 461 struct btrfs_device *device, u64 num_bytes, 462 u64 search_start, u64 *start, u64 *max_avail); 463 int find_free_dev_extent(struct btrfs_trans_handle *trans, 464 struct btrfs_device *device, u64 num_bytes, 465 u64 *start, u64 *max_avail); 466 void btrfs_dev_stat_inc_and_print(struct btrfs_device *dev, int index); 467 int btrfs_get_dev_stats(struct btrfs_fs_info *fs_info, 468 struct btrfs_ioctl_get_dev_stats *stats); 469 void btrfs_init_devices_late(struct btrfs_fs_info *fs_info); 470 int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info); 471 int btrfs_run_dev_stats(struct btrfs_trans_handle *trans, 472 struct btrfs_fs_info *fs_info); 473 void btrfs_rm_dev_replace_remove_srcdev(struct btrfs_fs_info *fs_info, 474 struct btrfs_device *srcdev); 475 void btrfs_rm_dev_replace_free_srcdev(struct btrfs_fs_info *fs_info, 476 struct btrfs_device *srcdev); 477 void btrfs_destroy_dev_replace_tgtdev(struct btrfs_fs_info *fs_info, 478 struct btrfs_device *tgtdev); 479 void btrfs_init_dev_replace_tgtdev_for_resume(struct btrfs_fs_info *fs_info, 480 struct btrfs_device *tgtdev); 481 void btrfs_scratch_superblocks(struct block_device *bdev, const char *device_path); 482 int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info, 483 u64 logical, u64 len); 484 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info, 485 u64 logical); 486 int btrfs_finish_chunk_alloc(struct btrfs_trans_handle *trans, 487 struct btrfs_fs_info *fs_info, 488 u64 chunk_offset, u64 chunk_size); 489 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, 490 struct btrfs_fs_info *fs_info, u64 chunk_offset); 491 492 static inline void btrfs_dev_stat_inc(struct btrfs_device *dev, 493 int index) 494 { 495 atomic_inc(dev->dev_stat_values + index); 496 /* 497 * This memory barrier orders stores updating statistics before stores 498 * updating dev_stats_ccnt. 499 * 500 * It pairs with smp_rmb() in btrfs_run_dev_stats(). 501 */ 502 smp_mb__before_atomic(); 503 atomic_inc(&dev->dev_stats_ccnt); 504 } 505 506 static inline int btrfs_dev_stat_read(struct btrfs_device *dev, 507 int index) 508 { 509 return atomic_read(dev->dev_stat_values + index); 510 } 511 512 static inline int btrfs_dev_stat_read_and_reset(struct btrfs_device *dev, 513 int index) 514 { 515 int ret; 516 517 ret = atomic_xchg(dev->dev_stat_values + index, 0); 518 /* 519 * atomic_xchg implies a full memory barriers as per atomic_t.txt: 520 * - RMW operations that have a return value are fully ordered; 521 * 522 * This implicit memory barriers is paired with the smp_rmb in 523 * btrfs_run_dev_stats 524 */ 525 atomic_inc(&dev->dev_stats_ccnt); 526 return ret; 527 } 528 529 static inline void btrfs_dev_stat_set(struct btrfs_device *dev, 530 int index, unsigned long val) 531 { 532 atomic_set(dev->dev_stat_values + index, val); 533 /* 534 * This memory barrier orders stores updating statistics before stores 535 * updating dev_stats_ccnt. 536 * 537 * It pairs with smp_rmb() in btrfs_run_dev_stats(). 538 */ 539 smp_mb__before_atomic(); 540 atomic_inc(&dev->dev_stats_ccnt); 541 } 542 543 static inline void btrfs_dev_stat_reset(struct btrfs_device *dev, 544 int index) 545 { 546 btrfs_dev_stat_set(dev, index, 0); 547 } 548 549 void btrfs_update_commit_device_size(struct btrfs_fs_info *fs_info); 550 void btrfs_update_commit_device_bytes_used(struct btrfs_fs_info *fs_info, 551 struct btrfs_transaction *transaction); 552 553 struct list_head *btrfs_get_fs_uuids(void); 554 void btrfs_set_fs_info_ptr(struct btrfs_fs_info *fs_info); 555 void btrfs_reset_fs_info_ptr(struct btrfs_fs_info *fs_info); 556 bool btrfs_check_rw_degradable(struct btrfs_fs_info *fs_info, 557 struct btrfs_device *failing_dev); 558 559 #endif 560