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