1 /* SPDX-License-Identifier: GPL-2.0 */
2
3 #ifndef BTRFS_FS_H
4 #define BTRFS_FS_H
5
6 #include <linux/blkdev.h>
7 #include <linux/sizes.h>
8 #include <linux/time64.h>
9 #include <linux/compiler.h>
10 #include <linux/math.h>
11 #include <linux/atomic.h>
12 #include <linux/percpu_counter.h>
13 #include <linux/completion.h>
14 #include <linux/lockdep.h>
15 #include <linux/spinlock.h>
16 #include <linux/mutex.h>
17 #include <linux/rwlock_types.h>
18 #include <linux/rwsem.h>
19 #include <linux/semaphore.h>
20 #include <linux/list.h>
21 #include <linux/radix-tree.h>
22 #include <linux/workqueue.h>
23 #include <linux/wait.h>
24 #include <linux/wait_bit.h>
25 #include <linux/sched.h>
26 #include <linux/rbtree.h>
27 #include <uapi/linux/btrfs.h>
28 #include <uapi/linux/btrfs_tree.h>
29 #include "extent-io-tree.h"
30 #include "async-thread.h"
31 #include "block-rsv.h"
32
33 struct inode;
34 struct super_block;
35 struct kobject;
36 struct reloc_control;
37 struct crypto_shash;
38 struct ulist;
39 struct btrfs_device;
40 struct btrfs_block_group;
41 struct btrfs_root;
42 struct btrfs_fs_devices;
43 struct btrfs_transaction;
44 struct btrfs_delayed_root;
45 struct btrfs_balance_control;
46 struct btrfs_subpage_info;
47 struct btrfs_stripe_hash_table;
48 struct btrfs_space_info;
49
50 #define BTRFS_MAX_EXTENT_SIZE SZ_128M
51
52 #define BTRFS_OLDEST_GENERATION 0ULL
53
54 #define BTRFS_EMPTY_DIR_SIZE 0
55
56 #define BTRFS_DIRTY_METADATA_THRESH SZ_32M
57
58 #define BTRFS_SUPER_INFO_OFFSET SZ_64K
59 #define BTRFS_SUPER_INFO_SIZE 4096
60 static_assert(sizeof(struct btrfs_super_block) == BTRFS_SUPER_INFO_SIZE);
61
62 /*
63 * Number of metadata items necessary for an unlink operation:
64 *
65 * 1 for the possible orphan item
66 * 1 for the dir item
67 * 1 for the dir index
68 * 1 for the inode ref
69 * 1 for the inode
70 * 1 for the parent inode
71 */
72 #define BTRFS_UNLINK_METADATA_UNITS 6
73
74 /*
75 * The reserved space at the beginning of each device. It covers the primary
76 * super block and leaves space for potential use by other tools like
77 * bootloaders or to lower potential damage of accidental overwrite.
78 */
79 #define BTRFS_DEVICE_RANGE_RESERVED (SZ_1M)
80 /*
81 * Runtime (in-memory) states of filesystem
82 */
83 enum {
84 /*
85 * Filesystem is being remounted, allow to skip some operations, like
86 * defrag
87 */
88 BTRFS_FS_STATE_REMOUNTING,
89 /* Filesystem in RO mode */
90 BTRFS_FS_STATE_RO,
91 /* Track if a transaction abort has been reported on this filesystem */
92 BTRFS_FS_STATE_TRANS_ABORTED,
93 /*
94 * Bio operations should be blocked on this filesystem because a source
95 * or target device is being destroyed as part of a device replace
96 */
97 BTRFS_FS_STATE_DEV_REPLACING,
98 /* The btrfs_fs_info created for self-tests */
99 BTRFS_FS_STATE_DUMMY_FS_INFO,
100
101 /* Checksum errors are ignored. */
102 BTRFS_FS_STATE_NO_DATA_CSUMS,
103 BTRFS_FS_STATE_SKIP_META_CSUMS,
104
105 /* Indicates there was an error cleaning up a log tree. */
106 BTRFS_FS_STATE_LOG_CLEANUP_ERROR,
107
108 BTRFS_FS_STATE_COUNT
109 };
110
111 enum {
112 BTRFS_FS_CLOSING_START,
113 BTRFS_FS_CLOSING_DONE,
114 BTRFS_FS_LOG_RECOVERING,
115 BTRFS_FS_OPEN,
116 BTRFS_FS_QUOTA_ENABLED,
117 BTRFS_FS_UPDATE_UUID_TREE_GEN,
118 BTRFS_FS_CREATING_FREE_SPACE_TREE,
119 BTRFS_FS_BTREE_ERR,
120 BTRFS_FS_LOG1_ERR,
121 BTRFS_FS_LOG2_ERR,
122 BTRFS_FS_QUOTA_OVERRIDE,
123 /* Used to record internally whether fs has been frozen */
124 BTRFS_FS_FROZEN,
125 /*
126 * Indicate that balance has been set up from the ioctl and is in the
127 * main phase. The fs_info::balance_ctl is initialized.
128 */
129 BTRFS_FS_BALANCE_RUNNING,
130
131 /*
132 * Indicate that relocation of a chunk has started, it's set per chunk
133 * and is toggled between chunks.
134 */
135 BTRFS_FS_RELOC_RUNNING,
136
137 /* Indicate that the cleaner thread is awake and doing something. */
138 BTRFS_FS_CLEANER_RUNNING,
139
140 /*
141 * The checksumming has an optimized version and is considered fast,
142 * so we don't need to offload checksums to workqueues.
143 */
144 BTRFS_FS_CSUM_IMPL_FAST,
145
146 /* Indicate that the discard workqueue can service discards. */
147 BTRFS_FS_DISCARD_RUNNING,
148
149 /* Indicate that we need to cleanup space cache v1 */
150 BTRFS_FS_CLEANUP_SPACE_CACHE_V1,
151
152 /* Indicate that we can't trust the free space tree for caching yet */
153 BTRFS_FS_FREE_SPACE_TREE_UNTRUSTED,
154
155 /* Indicate whether there are any tree modification log users */
156 BTRFS_FS_TREE_MOD_LOG_USERS,
157
158 /* Indicate that we want the transaction kthread to commit right now. */
159 BTRFS_FS_COMMIT_TRANS,
160
161 /* Indicate we have half completed snapshot deletions pending. */
162 BTRFS_FS_UNFINISHED_DROPS,
163
164 /* Indicate we have to finish a zone to do next allocation. */
165 BTRFS_FS_NEED_ZONE_FINISH,
166
167 /* Indicate that we want to commit the transaction. */
168 BTRFS_FS_NEED_TRANS_COMMIT,
169
170 /* This is set when active zone tracking is needed. */
171 BTRFS_FS_ACTIVE_ZONE_TRACKING,
172
173 /*
174 * Indicate if we have some features changed, this is mostly for
175 * cleaner thread to update the sysfs interface.
176 */
177 BTRFS_FS_FEATURE_CHANGED,
178
179 /*
180 * Indicate that we have found a tree block which is only aligned to
181 * sectorsize, but not to nodesize. This should be rare nowadays.
182 */
183 BTRFS_FS_UNALIGNED_TREE_BLOCK,
184
185 #if BITS_PER_LONG == 32
186 /* Indicate if we have error/warn message printed on 32bit systems */
187 BTRFS_FS_32BIT_ERROR,
188 BTRFS_FS_32BIT_WARN,
189 #endif
190 };
191
192 /*
193 * Flags for mount options.
194 *
195 * Note: don't forget to add new options to btrfs_show_options()
196 */
197 enum {
198 BTRFS_MOUNT_NODATASUM = (1ULL << 0),
199 BTRFS_MOUNT_NODATACOW = (1ULL << 1),
200 BTRFS_MOUNT_NOBARRIER = (1ULL << 2),
201 BTRFS_MOUNT_SSD = (1ULL << 3),
202 BTRFS_MOUNT_DEGRADED = (1ULL << 4),
203 BTRFS_MOUNT_COMPRESS = (1ULL << 5),
204 BTRFS_MOUNT_NOTREELOG = (1ULL << 6),
205 BTRFS_MOUNT_FLUSHONCOMMIT = (1ULL << 7),
206 BTRFS_MOUNT_SSD_SPREAD = (1ULL << 8),
207 BTRFS_MOUNT_NOSSD = (1ULL << 9),
208 BTRFS_MOUNT_DISCARD_SYNC = (1ULL << 10),
209 BTRFS_MOUNT_FORCE_COMPRESS = (1ULL << 11),
210 BTRFS_MOUNT_SPACE_CACHE = (1ULL << 12),
211 BTRFS_MOUNT_CLEAR_CACHE = (1ULL << 13),
212 BTRFS_MOUNT_USER_SUBVOL_RM_ALLOWED = (1ULL << 14),
213 BTRFS_MOUNT_ENOSPC_DEBUG = (1ULL << 15),
214 BTRFS_MOUNT_AUTO_DEFRAG = (1ULL << 16),
215 BTRFS_MOUNT_USEBACKUPROOT = (1ULL << 17),
216 BTRFS_MOUNT_SKIP_BALANCE = (1ULL << 18),
217 BTRFS_MOUNT_PANIC_ON_FATAL_ERROR = (1ULL << 19),
218 BTRFS_MOUNT_RESCAN_UUID_TREE = (1ULL << 20),
219 BTRFS_MOUNT_FRAGMENT_DATA = (1ULL << 21),
220 BTRFS_MOUNT_FRAGMENT_METADATA = (1ULL << 22),
221 BTRFS_MOUNT_FREE_SPACE_TREE = (1ULL << 23),
222 BTRFS_MOUNT_NOLOGREPLAY = (1ULL << 24),
223 BTRFS_MOUNT_REF_VERIFY = (1ULL << 25),
224 BTRFS_MOUNT_DISCARD_ASYNC = (1ULL << 26),
225 BTRFS_MOUNT_IGNOREBADROOTS = (1ULL << 27),
226 BTRFS_MOUNT_IGNOREDATACSUMS = (1ULL << 28),
227 BTRFS_MOUNT_NODISCARD = (1ULL << 29),
228 BTRFS_MOUNT_NOSPACECACHE = (1ULL << 30),
229 BTRFS_MOUNT_IGNOREMETACSUMS = (1ULL << 31),
230 BTRFS_MOUNT_IGNORESUPERFLAGS = (1ULL << 32),
231 };
232
233 /*
234 * Compat flags that we support. If any incompat flags are set other than the
235 * ones specified below then we will fail to mount
236 */
237 #define BTRFS_FEATURE_COMPAT_SUPP 0ULL
238 #define BTRFS_FEATURE_COMPAT_SAFE_SET 0ULL
239 #define BTRFS_FEATURE_COMPAT_SAFE_CLEAR 0ULL
240
241 #define BTRFS_FEATURE_COMPAT_RO_SUPP \
242 (BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE | \
243 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID | \
244 BTRFS_FEATURE_COMPAT_RO_VERITY | \
245 BTRFS_FEATURE_COMPAT_RO_BLOCK_GROUP_TREE)
246
247 #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET 0ULL
248 #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR 0ULL
249
250 #define BTRFS_FEATURE_INCOMPAT_SUPP_STABLE \
251 (BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF | \
252 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL | \
253 BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS | \
254 BTRFS_FEATURE_INCOMPAT_BIG_METADATA | \
255 BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO | \
256 BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD | \
257 BTRFS_FEATURE_INCOMPAT_RAID56 | \
258 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF | \
259 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA | \
260 BTRFS_FEATURE_INCOMPAT_NO_HOLES | \
261 BTRFS_FEATURE_INCOMPAT_METADATA_UUID | \
262 BTRFS_FEATURE_INCOMPAT_RAID1C34 | \
263 BTRFS_FEATURE_INCOMPAT_ZONED | \
264 BTRFS_FEATURE_INCOMPAT_SIMPLE_QUOTA)
265
266 #ifdef CONFIG_BTRFS_DEBUG
267 /*
268 * Features under developmen like Extent tree v2 support is enabled
269 * only under CONFIG_BTRFS_DEBUG.
270 */
271 #define BTRFS_FEATURE_INCOMPAT_SUPP \
272 (BTRFS_FEATURE_INCOMPAT_SUPP_STABLE | \
273 BTRFS_FEATURE_INCOMPAT_RAID_STRIPE_TREE | \
274 BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2)
275
276 #else
277
278 #define BTRFS_FEATURE_INCOMPAT_SUPP \
279 (BTRFS_FEATURE_INCOMPAT_SUPP_STABLE)
280
281 #endif
282
283 #define BTRFS_FEATURE_INCOMPAT_SAFE_SET \
284 (BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
285 #define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR 0ULL
286
287 #define BTRFS_DEFAULT_COMMIT_INTERVAL (30)
288 #define BTRFS_DEFAULT_MAX_INLINE (2048)
289
290 struct btrfs_dev_replace {
291 /* See #define above */
292 u64 replace_state;
293 /* Seconds since 1-Jan-1970 */
294 time64_t time_started;
295 /* Seconds since 1-Jan-1970 */
296 time64_t time_stopped;
297 atomic64_t num_write_errors;
298 atomic64_t num_uncorrectable_read_errors;
299
300 u64 cursor_left;
301 u64 committed_cursor_left;
302 u64 cursor_left_last_write_of_item;
303 u64 cursor_right;
304
305 /* See #define above */
306 u64 cont_reading_from_srcdev_mode;
307
308 int is_valid;
309 int item_needs_writeback;
310 struct btrfs_device *srcdev;
311 struct btrfs_device *tgtdev;
312
313 struct mutex lock_finishing_cancel_unmount;
314 struct rw_semaphore rwsem;
315
316 struct btrfs_scrub_progress scrub_progress;
317
318 struct percpu_counter bio_counter;
319 wait_queue_head_t replace_wait;
320 };
321
322 /*
323 * Free clusters are used to claim free space in relatively large chunks,
324 * allowing us to do less seeky writes. They are used for all metadata
325 * allocations. In ssd_spread mode they are also used for data allocations.
326 */
327 struct btrfs_free_cluster {
328 spinlock_t lock;
329 spinlock_t refill_lock;
330 struct rb_root root;
331
332 /* Largest extent in this cluster */
333 u64 max_size;
334
335 /* First extent starting offset */
336 u64 window_start;
337
338 /* We did a full search and couldn't create a cluster */
339 bool fragmented;
340
341 struct btrfs_block_group *block_group;
342 /*
343 * When a cluster is allocated from a block group, we put the cluster
344 * onto a list in the block group so that it can be freed before the
345 * block group is freed.
346 */
347 struct list_head block_group_list;
348 };
349
350 /* Discard control. */
351 /*
352 * Async discard uses multiple lists to differentiate the discard filter
353 * parameters. Index 0 is for completely free block groups where we need to
354 * ensure the entire block group is trimmed without being lossy. Indices
355 * afterwards represent monotonically decreasing discard filter sizes to
356 * prioritize what should be discarded next.
357 */
358 #define BTRFS_NR_DISCARD_LISTS 3
359 #define BTRFS_DISCARD_INDEX_UNUSED 0
360 #define BTRFS_DISCARD_INDEX_START 1
361
362 struct btrfs_discard_ctl {
363 struct workqueue_struct *discard_workers;
364 struct delayed_work work;
365 spinlock_t lock;
366 struct btrfs_block_group *block_group;
367 struct list_head discard_list[BTRFS_NR_DISCARD_LISTS];
368 u64 prev_discard;
369 u64 prev_discard_time;
370 atomic_t discardable_extents;
371 atomic64_t discardable_bytes;
372 u64 max_discard_size;
373 u64 delay_ms;
374 u32 iops_limit;
375 u32 kbps_limit;
376 u64 discard_extent_bytes;
377 u64 discard_bitmap_bytes;
378 atomic64_t discard_bytes_saved;
379 };
380
381 /*
382 * Exclusive operations (device replace, resize, device add/remove, balance)
383 */
384 enum btrfs_exclusive_operation {
385 BTRFS_EXCLOP_NONE,
386 BTRFS_EXCLOP_BALANCE_PAUSED,
387 BTRFS_EXCLOP_BALANCE,
388 BTRFS_EXCLOP_DEV_ADD,
389 BTRFS_EXCLOP_DEV_REMOVE,
390 BTRFS_EXCLOP_DEV_REPLACE,
391 BTRFS_EXCLOP_RESIZE,
392 BTRFS_EXCLOP_SWAP_ACTIVATE,
393 };
394
395 /* Store data about transaction commits, exported via sysfs. */
396 struct btrfs_commit_stats {
397 /* Total number of commits */
398 u64 commit_count;
399 /* The maximum commit duration so far in ns */
400 u64 max_commit_dur;
401 /* The last commit duration in ns */
402 u64 last_commit_dur;
403 /* The total commit duration in ns */
404 u64 total_commit_dur;
405 };
406
407 struct btrfs_fs_info {
408 u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
409 unsigned long flags;
410 struct btrfs_root *tree_root;
411 struct btrfs_root *chunk_root;
412 struct btrfs_root *dev_root;
413 struct btrfs_root *fs_root;
414 struct btrfs_root *quota_root;
415 struct btrfs_root *uuid_root;
416 struct btrfs_root *data_reloc_root;
417 struct btrfs_root *block_group_root;
418 struct btrfs_root *stripe_root;
419
420 /* The log root tree is a directory of all the other log roots */
421 struct btrfs_root *log_root_tree;
422
423 /* The tree that holds the global roots (csum, extent, etc) */
424 rwlock_t global_root_lock;
425 struct rb_root global_root_tree;
426
427 spinlock_t fs_roots_radix_lock;
428 struct radix_tree_root fs_roots_radix;
429
430 /* Block group cache stuff */
431 rwlock_t block_group_cache_lock;
432 struct rb_root_cached block_group_cache_tree;
433
434 /* Keep track of unallocated space */
435 atomic64_t free_chunk_space;
436
437 /* Track ranges which are used by log trees blocks/logged data extents */
438 struct extent_io_tree excluded_extents;
439
440 /* logical->physical extent mapping */
441 struct rb_root_cached mapping_tree;
442 rwlock_t mapping_tree_lock;
443
444 /*
445 * Block reservation for extent, checksum, root tree and delayed dir
446 * index item.
447 */
448 struct btrfs_block_rsv global_block_rsv;
449 /* Block reservation for metadata operations */
450 struct btrfs_block_rsv trans_block_rsv;
451 /* Block reservation for chunk tree */
452 struct btrfs_block_rsv chunk_block_rsv;
453 /* Block reservation for delayed operations */
454 struct btrfs_block_rsv delayed_block_rsv;
455 /* Block reservation for delayed refs */
456 struct btrfs_block_rsv delayed_refs_rsv;
457
458 struct btrfs_block_rsv empty_block_rsv;
459
460 /*
461 * Updated while holding the lock 'trans_lock'. Due to the life cycle of
462 * a transaction, it can be directly read while holding a transaction
463 * handle, everywhere else must be read with btrfs_get_fs_generation().
464 * Should always be updated using btrfs_set_fs_generation().
465 */
466 u64 generation;
467 /*
468 * Always use btrfs_get_last_trans_committed() and
469 * btrfs_set_last_trans_committed() to read and update this field.
470 */
471 u64 last_trans_committed;
472 /*
473 * Generation of the last transaction used for block group relocation
474 * since the filesystem was last mounted (or 0 if none happened yet).
475 * Must be written and read while holding btrfs_fs_info::commit_root_sem.
476 */
477 u64 last_reloc_trans;
478
479 /*
480 * This is updated to the current trans every time a full commit is
481 * required instead of the faster short fsync log commits
482 */
483 u64 last_trans_log_full_commit;
484 unsigned long long mount_opt;
485
486 unsigned long compress_type:4;
487 unsigned int compress_level;
488 u32 commit_interval;
489 /*
490 * It is a suggestive number, the read side is safe even it gets a
491 * wrong number because we will write out the data into a regular
492 * extent. The write side(mount/remount) is under ->s_umount lock,
493 * so it is also safe.
494 */
495 u64 max_inline;
496
497 struct btrfs_transaction *running_transaction;
498 wait_queue_head_t transaction_throttle;
499 wait_queue_head_t transaction_wait;
500 wait_queue_head_t transaction_blocked_wait;
501 wait_queue_head_t async_submit_wait;
502
503 /*
504 * Used to protect the incompat_flags, compat_flags, compat_ro_flags
505 * when they are updated.
506 *
507 * Because we do not clear the flags for ever, so we needn't use
508 * the lock on the read side.
509 *
510 * We also needn't use the lock when we mount the fs, because
511 * there is no other task which will update the flag.
512 */
513 spinlock_t super_lock;
514 struct btrfs_super_block *super_copy;
515 struct btrfs_super_block *super_for_commit;
516 struct super_block *sb;
517 struct inode *btree_inode;
518 struct mutex tree_log_mutex;
519 struct mutex transaction_kthread_mutex;
520 struct mutex cleaner_mutex;
521 struct mutex chunk_mutex;
522
523 /*
524 * This is taken to make sure we don't set block groups ro after the
525 * free space cache has been allocated on them.
526 */
527 struct mutex ro_block_group_mutex;
528
529 /*
530 * This is used during read/modify/write to make sure no two ios are
531 * trying to mod the same stripe at the same time.
532 */
533 struct btrfs_stripe_hash_table *stripe_hash_table;
534
535 /*
536 * This protects the ordered operations list only while we are
537 * processing all of the entries on it. This way we make sure the
538 * commit code doesn't find the list temporarily empty because another
539 * function happens to be doing non-waiting preflush before jumping
540 * into the main commit.
541 */
542 struct mutex ordered_operations_mutex;
543
544 struct rw_semaphore commit_root_sem;
545
546 struct rw_semaphore cleanup_work_sem;
547
548 struct rw_semaphore subvol_sem;
549
550 spinlock_t trans_lock;
551 /*
552 * The reloc mutex goes with the trans lock, it is taken during commit
553 * to protect us from the relocation code.
554 */
555 struct mutex reloc_mutex;
556
557 struct list_head trans_list;
558 struct list_head dead_roots;
559 struct list_head caching_block_groups;
560
561 spinlock_t delayed_iput_lock;
562 struct list_head delayed_iputs;
563 atomic_t nr_delayed_iputs;
564 wait_queue_head_t delayed_iputs_wait;
565
566 atomic64_t tree_mod_seq;
567
568 /* This protects tree_mod_log and tree_mod_seq_list */
569 rwlock_t tree_mod_log_lock;
570 struct rb_root tree_mod_log;
571 struct list_head tree_mod_seq_list;
572
573 atomic_t async_delalloc_pages;
574
575 /* This is used to protect the following list -- ordered_roots. */
576 spinlock_t ordered_root_lock;
577
578 /*
579 * All fs/file tree roots in which there are data=ordered extents
580 * pending writeback are added into this list.
581 *
582 * These can span multiple transactions and basically include every
583 * dirty data page that isn't from nodatacow.
584 */
585 struct list_head ordered_roots;
586
587 struct mutex delalloc_root_mutex;
588 spinlock_t delalloc_root_lock;
589 /* All fs/file tree roots that have delalloc inodes. */
590 struct list_head delalloc_roots;
591
592 /*
593 * There is a pool of worker threads for checksumming during writes and
594 * a pool for checksumming after reads. This is because readers can
595 * run with FS locks held, and the writers may be waiting for those
596 * locks. We don't want ordering in the pending list to cause
597 * deadlocks, and so the two are serviced separately.
598 *
599 * A third pool does submit_bio to avoid deadlocking with the other two.
600 */
601 struct btrfs_workqueue *workers;
602 struct btrfs_workqueue *delalloc_workers;
603 struct btrfs_workqueue *flush_workers;
604 struct workqueue_struct *endio_workers;
605 struct workqueue_struct *endio_meta_workers;
606 struct workqueue_struct *rmw_workers;
607 struct workqueue_struct *compressed_write_workers;
608 struct btrfs_workqueue *endio_write_workers;
609 struct btrfs_workqueue *endio_freespace_worker;
610 struct btrfs_workqueue *caching_workers;
611
612 /*
613 * Fixup workers take dirty pages that didn't properly go through the
614 * cow mechanism and make them safe to write. It happens for the
615 * sys_munmap function call path.
616 */
617 struct btrfs_workqueue *fixup_workers;
618 struct btrfs_workqueue *delayed_workers;
619
620 struct task_struct *transaction_kthread;
621 struct task_struct *cleaner_kthread;
622 u32 thread_pool_size;
623
624 struct kobject *space_info_kobj;
625 struct kobject *qgroups_kobj;
626 struct kobject *discard_kobj;
627
628 /* Used to keep from writing metadata until there is a nice batch */
629 struct percpu_counter dirty_metadata_bytes;
630 struct percpu_counter delalloc_bytes;
631 struct percpu_counter ordered_bytes;
632 s32 dirty_metadata_batch;
633 s32 delalloc_batch;
634
635 struct percpu_counter evictable_extent_maps;
636 spinlock_t extent_map_shrinker_lock;
637 u64 extent_map_shrinker_last_root;
638 u64 extent_map_shrinker_last_ino;
639
640 /* Protected by 'trans_lock'. */
641 struct list_head dirty_cowonly_roots;
642
643 struct btrfs_fs_devices *fs_devices;
644
645 /*
646 * The space_info list is effectively read only after initial setup.
647 * It is populated at mount time and cleaned up after all block groups
648 * are removed. RCU is used to protect it.
649 */
650 struct list_head space_info;
651
652 struct btrfs_space_info *data_sinfo;
653
654 struct reloc_control *reloc_ctl;
655
656 /* data_alloc_cluster is only used in ssd_spread mode */
657 struct btrfs_free_cluster data_alloc_cluster;
658
659 /* All metadata allocations go through this cluster. */
660 struct btrfs_free_cluster meta_alloc_cluster;
661
662 /* Auto defrag inodes go here. */
663 spinlock_t defrag_inodes_lock;
664 struct rb_root defrag_inodes;
665 atomic_t defrag_running;
666
667 /* Used to protect avail_{data, metadata, system}_alloc_bits */
668 seqlock_t profiles_lock;
669 /*
670 * These three are in extended format (availability of single chunks is
671 * denoted by BTRFS_AVAIL_ALLOC_BIT_SINGLE bit, other types are denoted
672 * by corresponding BTRFS_BLOCK_GROUP_* bits)
673 */
674 u64 avail_data_alloc_bits;
675 u64 avail_metadata_alloc_bits;
676 u64 avail_system_alloc_bits;
677
678 /* Balance state */
679 spinlock_t balance_lock;
680 struct mutex balance_mutex;
681 atomic_t balance_pause_req;
682 atomic_t balance_cancel_req;
683 struct btrfs_balance_control *balance_ctl;
684 wait_queue_head_t balance_wait_q;
685
686 /* Cancellation requests for chunk relocation */
687 atomic_t reloc_cancel_req;
688
689 u32 data_chunk_allocations;
690 u32 metadata_ratio;
691
692 void *bdev_holder;
693
694 /* Private scrub information */
695 struct mutex scrub_lock;
696 atomic_t scrubs_running;
697 atomic_t scrub_pause_req;
698 atomic_t scrubs_paused;
699 atomic_t scrub_cancel_req;
700 wait_queue_head_t scrub_pause_wait;
701 /*
702 * The worker pointers are NULL iff the refcount is 0, ie. scrub is not
703 * running.
704 */
705 refcount_t scrub_workers_refcnt;
706 struct workqueue_struct *scrub_workers;
707 struct btrfs_subpage_info *subpage_info;
708
709 struct btrfs_discard_ctl discard_ctl;
710
711 /* Is qgroup tracking in a consistent state? */
712 u64 qgroup_flags;
713
714 /* Holds configuration and tracking. Protected by qgroup_lock. */
715 struct rb_root qgroup_tree;
716 spinlock_t qgroup_lock;
717
718 /*
719 * Used to avoid frequently calling ulist_alloc()/ulist_free()
720 * when doing qgroup accounting, it must be protected by qgroup_lock.
721 */
722 struct ulist *qgroup_ulist;
723
724 /*
725 * Protect user change for quota operations. If a transaction is needed,
726 * it must be started before locking this lock.
727 */
728 struct mutex qgroup_ioctl_lock;
729
730 /* List of dirty qgroups to be written at next commit. */
731 struct list_head dirty_qgroups;
732
733 /* Used by qgroup for an efficient tree traversal. */
734 u64 qgroup_seq;
735
736 /* Qgroup rescan items. */
737 /* Protects the progress item */
738 struct mutex qgroup_rescan_lock;
739 struct btrfs_key qgroup_rescan_progress;
740 struct btrfs_workqueue *qgroup_rescan_workers;
741 struct completion qgroup_rescan_completion;
742 struct btrfs_work qgroup_rescan_work;
743 /* Protected by qgroup_rescan_lock */
744 bool qgroup_rescan_running;
745 u8 qgroup_drop_subtree_thres;
746 u64 qgroup_enable_gen;
747
748 /*
749 * If this is not 0, then it indicates a serious filesystem error has
750 * happened and it contains that error (negative errno value).
751 */
752 int fs_error;
753
754 /* Filesystem state */
755 unsigned long fs_state;
756
757 struct btrfs_delayed_root *delayed_root;
758
759 /* Extent buffer radix tree */
760 spinlock_t buffer_lock;
761 /* Entries are eb->start / sectorsize */
762 struct radix_tree_root buffer_radix;
763
764 /* Next backup root to be overwritten */
765 int backup_root_index;
766
767 /* Device replace state */
768 struct btrfs_dev_replace dev_replace;
769
770 struct semaphore uuid_tree_rescan_sem;
771
772 /* Used to reclaim the metadata space in the background. */
773 struct work_struct async_reclaim_work;
774 struct work_struct async_data_reclaim_work;
775 struct work_struct preempt_reclaim_work;
776
777 /* Reclaim partially filled block groups in the background */
778 struct work_struct reclaim_bgs_work;
779 /* Protected by unused_bgs_lock. */
780 struct list_head reclaim_bgs;
781 int bg_reclaim_threshold;
782
783 /* Protects the lists unused_bgs and reclaim_bgs. */
784 spinlock_t unused_bgs_lock;
785 /* Protected by unused_bgs_lock. */
786 struct list_head unused_bgs;
787 struct mutex unused_bg_unpin_mutex;
788 /* Protect block groups that are going to be deleted */
789 struct mutex reclaim_bgs_lock;
790
791 /* Cached block sizes */
792 u32 nodesize;
793 u32 sectorsize;
794 /* ilog2 of sectorsize, use to avoid 64bit division */
795 u32 sectorsize_bits;
796 u32 csum_size;
797 u32 csums_per_leaf;
798 u32 stripesize;
799
800 /*
801 * Maximum size of an extent. BTRFS_MAX_EXTENT_SIZE on regular
802 * filesystem, on zoned it depends on the device constraints.
803 */
804 u64 max_extent_size;
805
806 /* Block groups and devices containing active swapfiles. */
807 spinlock_t swapfile_pins_lock;
808 struct rb_root swapfile_pins;
809
810 struct crypto_shash *csum_shash;
811
812 /* Type of exclusive operation running, protected by super_lock */
813 enum btrfs_exclusive_operation exclusive_operation;
814
815 /*
816 * Zone size > 0 when in ZONED mode, otherwise it's used for a check
817 * if the mode is enabled
818 */
819 u64 zone_size;
820
821 /* Constraints for ZONE_APPEND commands: */
822 struct queue_limits limits;
823 u64 max_zone_append_size;
824
825 struct mutex zoned_meta_io_lock;
826 spinlock_t treelog_bg_lock;
827 u64 treelog_bg;
828
829 /*
830 * Start of the dedicated data relocation block group, protected by
831 * relocation_bg_lock.
832 */
833 spinlock_t relocation_bg_lock;
834 u64 data_reloc_bg;
835 struct mutex zoned_data_reloc_io_lock;
836
837 struct btrfs_block_group *active_meta_bg;
838 struct btrfs_block_group *active_system_bg;
839
840 u64 nr_global_roots;
841
842 spinlock_t zone_active_bgs_lock;
843 struct list_head zone_active_bgs;
844
845 /* Updates are not protected by any lock */
846 struct btrfs_commit_stats commit_stats;
847
848 /*
849 * Last generation where we dropped a non-relocation root.
850 * Use btrfs_set_last_root_drop_gen() and btrfs_get_last_root_drop_gen()
851 * to change it and to read it, respectively.
852 */
853 u64 last_root_drop_gen;
854
855 /*
856 * Annotations for transaction events (structures are empty when
857 * compiled without lockdep).
858 */
859 struct lockdep_map btrfs_trans_num_writers_map;
860 struct lockdep_map btrfs_trans_num_extwriters_map;
861 struct lockdep_map btrfs_state_change_map[4];
862 struct lockdep_map btrfs_trans_pending_ordered_map;
863 struct lockdep_map btrfs_ordered_extent_map;
864
865 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
866 spinlock_t ref_verify_lock;
867 struct rb_root block_tree;
868 #endif
869
870 #ifdef CONFIG_BTRFS_DEBUG
871 struct kobject *debug_kobj;
872 struct list_head allocated_roots;
873
874 spinlock_t eb_leak_lock;
875 struct list_head allocated_ebs;
876 #endif
877 };
878
879 #define page_to_inode(_page) (BTRFS_I(_Generic((_page), \
880 struct page *: (_page))->mapping->host))
881 #define folio_to_inode(_folio) (BTRFS_I(_Generic((_folio), \
882 struct folio *: (_folio))->mapping->host))
883
884 #define page_to_fs_info(_page) (page_to_inode(_page)->root->fs_info)
885 #define folio_to_fs_info(_folio) (folio_to_inode(_folio)->root->fs_info)
886
887 #define inode_to_fs_info(_inode) (BTRFS_I(_Generic((_inode), \
888 struct inode *: (_inode)))->root->fs_info)
889
890 static inline u64 btrfs_get_fs_generation(const struct btrfs_fs_info *fs_info)
891 {
892 return READ_ONCE(fs_info->generation);
893 }
894
895 static inline void btrfs_set_fs_generation(struct btrfs_fs_info *fs_info, u64 gen)
896 {
897 WRITE_ONCE(fs_info->generation, gen);
898 }
899
900 static inline u64 btrfs_get_last_trans_committed(const struct btrfs_fs_info *fs_info)
901 {
902 return READ_ONCE(fs_info->last_trans_committed);
903 }
904
905 static inline void btrfs_set_last_trans_committed(struct btrfs_fs_info *fs_info, u64 gen)
906 {
907 WRITE_ONCE(fs_info->last_trans_committed, gen);
908 }
909
910 static inline void btrfs_set_last_root_drop_gen(struct btrfs_fs_info *fs_info,
911 u64 gen)
912 {
913 WRITE_ONCE(fs_info->last_root_drop_gen, gen);
914 }
915
916 static inline u64 btrfs_get_last_root_drop_gen(const struct btrfs_fs_info *fs_info)
917 {
918 return READ_ONCE(fs_info->last_root_drop_gen);
919 }
920
921 /*
922 * Take the number of bytes to be checksummed and figure out how many leaves
923 * it would require to store the csums for that many bytes.
924 */
925 static inline u64 btrfs_csum_bytes_to_leaves(
926 const struct btrfs_fs_info *fs_info, u64 csum_bytes)
927 {
928 const u64 num_csums = csum_bytes >> fs_info->sectorsize_bits;
929
930 return DIV_ROUND_UP_ULL(num_csums, fs_info->csums_per_leaf);
931 }
932
933 /*
934 * Use this if we would be adding new items, as we could split nodes as we cow
935 * down the tree.
936 */
937 static inline u64 btrfs_calc_insert_metadata_size(const struct btrfs_fs_info *fs_info,
938 unsigned num_items)
939 {
940 return (u64)fs_info->nodesize * BTRFS_MAX_LEVEL * 2 * num_items;
941 }
942
943 /*
944 * Doing a truncate or a modification won't result in new nodes or leaves, just
945 * what we need for COW.
946 */
947 static inline u64 btrfs_calc_metadata_size(const struct btrfs_fs_info *fs_info,
948 unsigned num_items)
949 {
950 return (u64)fs_info->nodesize * BTRFS_MAX_LEVEL * num_items;
951 }
952
953 #define BTRFS_MAX_EXTENT_ITEM_SIZE(r) ((BTRFS_LEAF_DATA_SIZE(r->fs_info) >> 4) - \
954 sizeof(struct btrfs_item))
955
956 static inline bool btrfs_is_zoned(const struct btrfs_fs_info *fs_info)
957 {
958 return IS_ENABLED(CONFIG_BLK_DEV_ZONED) && fs_info->zone_size > 0;
959 }
960
961 /*
962 * Count how many fs_info->max_extent_size cover the @size
963 */
964 static inline u32 count_max_extents(const struct btrfs_fs_info *fs_info, u64 size)
965 {
966 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
967 if (!fs_info)
968 return div_u64(size + BTRFS_MAX_EXTENT_SIZE - 1, BTRFS_MAX_EXTENT_SIZE);
969 #endif
970
971 return div_u64(size + fs_info->max_extent_size - 1, fs_info->max_extent_size);
972 }
973
974 bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
975 enum btrfs_exclusive_operation type);
976 bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
977 enum btrfs_exclusive_operation type);
978 void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info);
979 void btrfs_exclop_finish(struct btrfs_fs_info *fs_info);
980 void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
981 enum btrfs_exclusive_operation op);
982
983 int btrfs_check_ioctl_vol_args_path(const struct btrfs_ioctl_vol_args *vol_args);
984
985 /* Compatibility and incompatibility defines */
986 void __btrfs_set_fs_incompat(struct btrfs_fs_info *fs_info, u64 flag,
987 const char *name);
988 void __btrfs_clear_fs_incompat(struct btrfs_fs_info *fs_info, u64 flag,
989 const char *name);
990 void __btrfs_set_fs_compat_ro(struct btrfs_fs_info *fs_info, u64 flag,
991 const char *name);
992 void __btrfs_clear_fs_compat_ro(struct btrfs_fs_info *fs_info, u64 flag,
993 const char *name);
994
995 #define __btrfs_fs_incompat(fs_info, flags) \
996 (!!(btrfs_super_incompat_flags((fs_info)->super_copy) & (flags)))
997
998 #define __btrfs_fs_compat_ro(fs_info, flags) \
999 (!!(btrfs_super_compat_ro_flags((fs_info)->super_copy) & (flags)))
1000
1001 #define btrfs_set_fs_incompat(__fs_info, opt) \
1002 __btrfs_set_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt, #opt)
1003
1004 #define btrfs_clear_fs_incompat(__fs_info, opt) \
1005 __btrfs_clear_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt, #opt)
1006
1007 #define btrfs_fs_incompat(fs_info, opt) \
1008 __btrfs_fs_incompat((fs_info), BTRFS_FEATURE_INCOMPAT_##opt)
1009
1010 #define btrfs_set_fs_compat_ro(__fs_info, opt) \
1011 __btrfs_set_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt, #opt)
1012
1013 #define btrfs_clear_fs_compat_ro(__fs_info, opt) \
1014 __btrfs_clear_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt, #opt)
1015
1016 #define btrfs_fs_compat_ro(fs_info, opt) \
1017 __btrfs_fs_compat_ro((fs_info), BTRFS_FEATURE_COMPAT_RO_##opt)
1018
1019 #define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt)
1020 #define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt)
1021 #define btrfs_raw_test_opt(o, opt) ((o) & BTRFS_MOUNT_##opt)
1022 #define btrfs_test_opt(fs_info, opt) ((fs_info)->mount_opt & \
1023 BTRFS_MOUNT_##opt)
1024
1025 static inline int btrfs_fs_closing(const struct btrfs_fs_info *fs_info)
1026 {
1027 /* Do it this way so we only ever do one test_bit in the normal case. */
1028 if (test_bit(BTRFS_FS_CLOSING_START, &fs_info->flags)) {
1029 if (test_bit(BTRFS_FS_CLOSING_DONE, &fs_info->flags))
1030 return 2;
1031 return 1;
1032 }
1033 return 0;
1034 }
1035
1036 /*
1037 * If we remount the fs to be R/O or umount the fs, the cleaner needn't do
1038 * anything except sleeping. This function is used to check the status of
1039 * the fs.
1040 * We check for BTRFS_FS_STATE_RO to avoid races with a concurrent remount,
1041 * since setting and checking for SB_RDONLY in the superblock's flags is not
1042 * atomic.
1043 */
1044 static inline int btrfs_need_cleaner_sleep(const struct btrfs_fs_info *fs_info)
1045 {
1046 return test_bit(BTRFS_FS_STATE_RO, &fs_info->fs_state) ||
1047 btrfs_fs_closing(fs_info);
1048 }
1049
1050 static inline void btrfs_wake_unfinished_drop(struct btrfs_fs_info *fs_info)
1051 {
1052 clear_and_wake_up_bit(BTRFS_FS_UNFINISHED_DROPS, &fs_info->flags);
1053 }
1054
1055 #define BTRFS_FS_ERROR(fs_info) (READ_ONCE((fs_info)->fs_error))
1056
1057 #define BTRFS_FS_LOG_CLEANUP_ERROR(fs_info) \
1058 (unlikely(test_bit(BTRFS_FS_STATE_LOG_CLEANUP_ERROR, \
1059 &(fs_info)->fs_state)))
1060
1061 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1062
1063 #define EXPORT_FOR_TESTS
1064
1065 static inline int btrfs_is_testing(const struct btrfs_fs_info *fs_info)
1066 {
1067 return test_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);
1068 }
1069
1070 void btrfs_test_destroy_inode(struct inode *inode);
1071
1072 #else
1073
1074 #define EXPORT_FOR_TESTS static
1075
1076 static inline int btrfs_is_testing(const struct btrfs_fs_info *fs_info)
1077 {
1078 return 0;
1079 }
1080 #endif
1081
1082 #endif
1083
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