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

source code of linux/fs/btrfs/fs.h