1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_H
3 #define _BCACHEFS_H
4
5 /*
6 * SOME HIGH LEVEL CODE DOCUMENTATION:
7 *
8 * Bcache mostly works with cache sets, cache devices, and backing devices.
9 *
10 * Support for multiple cache devices hasn't quite been finished off yet, but
11 * it's about 95% plumbed through. A cache set and its cache devices is sort of
12 * like a md raid array and its component devices. Most of the code doesn't care
13 * about individual cache devices, the main abstraction is the cache set.
14 *
15 * Multiple cache devices is intended to give us the ability to mirror dirty
16 * cached data and metadata, without mirroring clean cached data.
17 *
18 * Backing devices are different, in that they have a lifetime independent of a
19 * cache set. When you register a newly formatted backing device it'll come up
20 * in passthrough mode, and then you can attach and detach a backing device from
21 * a cache set at runtime - while it's mounted and in use. Detaching implicitly
22 * invalidates any cached data for that backing device.
23 *
24 * A cache set can have multiple (many) backing devices attached to it.
25 *
26 * There's also flash only volumes - this is the reason for the distinction
27 * between struct cached_dev and struct bcache_device. A flash only volume
28 * works much like a bcache device that has a backing device, except the
29 * "cached" data is always dirty. The end result is that we get thin
30 * provisioning with very little additional code.
31 *
32 * Flash only volumes work but they're not production ready because the moving
33 * garbage collector needs more work. More on that later.
34 *
35 * BUCKETS/ALLOCATION:
36 *
37 * Bcache is primarily designed for caching, which means that in normal
38 * operation all of our available space will be allocated. Thus, we need an
39 * efficient way of deleting things from the cache so we can write new things to
40 * it.
41 *
42 * To do this, we first divide the cache device up into buckets. A bucket is the
43 * unit of allocation; they're typically around 1 mb - anywhere from 128k to 2M+
44 * works efficiently.
45 *
46 * Each bucket has a 16 bit priority, and an 8 bit generation associated with
47 * it. The gens and priorities for all the buckets are stored contiguously and
48 * packed on disk (in a linked list of buckets - aside from the superblock, all
49 * of bcache's metadata is stored in buckets).
50 *
51 * The priority is used to implement an LRU. We reset a bucket's priority when
52 * we allocate it or on cache it, and every so often we decrement the priority
53 * of each bucket. It could be used to implement something more sophisticated,
54 * if anyone ever gets around to it.
55 *
56 * The generation is used for invalidating buckets. Each pointer also has an 8
57 * bit generation embedded in it; for a pointer to be considered valid, its gen
58 * must match the gen of the bucket it points into. Thus, to reuse a bucket all
59 * we have to do is increment its gen (and write its new gen to disk; we batch
60 * this up).
61 *
62 * Bcache is entirely COW - we never write twice to a bucket, even buckets that
63 * contain metadata (including btree nodes).
64 *
65 * THE BTREE:
66 *
67 * Bcache is in large part design around the btree.
68 *
69 * At a high level, the btree is just an index of key -> ptr tuples.
70 *
71 * Keys represent extents, and thus have a size field. Keys also have a variable
72 * number of pointers attached to them (potentially zero, which is handy for
73 * invalidating the cache).
74 *
75 * The key itself is an inode:offset pair. The inode number corresponds to a
76 * backing device or a flash only volume. The offset is the ending offset of the
77 * extent within the inode - not the starting offset; this makes lookups
78 * slightly more convenient.
79 *
80 * Pointers contain the cache device id, the offset on that device, and an 8 bit
81 * generation number. More on the gen later.
82 *
83 * Index lookups are not fully abstracted - cache lookups in particular are
84 * still somewhat mixed in with the btree code, but things are headed in that
85 * direction.
86 *
87 * Updates are fairly well abstracted, though. There are two different ways of
88 * updating the btree; insert and replace.
89 *
90 * BTREE_INSERT will just take a list of keys and insert them into the btree -
91 * overwriting (possibly only partially) any extents they overlap with. This is
92 * used to update the index after a write.
93 *
94 * BTREE_REPLACE is really cmpxchg(); it inserts a key into the btree iff it is
95 * overwriting a key that matches another given key. This is used for inserting
96 * data into the cache after a cache miss, and for background writeback, and for
97 * the moving garbage collector.
98 *
99 * There is no "delete" operation; deleting things from the index is
100 * accomplished by either by invalidating pointers (by incrementing a bucket's
101 * gen) or by inserting a key with 0 pointers - which will overwrite anything
102 * previously present at that location in the index.
103 *
104 * This means that there are always stale/invalid keys in the btree. They're
105 * filtered out by the code that iterates through a btree node, and removed when
106 * a btree node is rewritten.
107 *
108 * BTREE NODES:
109 *
110 * Our unit of allocation is a bucket, and we can't arbitrarily allocate and
111 * free smaller than a bucket - so, that's how big our btree nodes are.
112 *
113 * (If buckets are really big we'll only use part of the bucket for a btree node
114 * - no less than 1/4th - but a bucket still contains no more than a single
115 * btree node. I'd actually like to change this, but for now we rely on the
116 * bucket's gen for deleting btree nodes when we rewrite/split a node.)
117 *
118 * Anyways, btree nodes are big - big enough to be inefficient with a textbook
119 * btree implementation.
120 *
121 * The way this is solved is that btree nodes are internally log structured; we
122 * can append new keys to an existing btree node without rewriting it. This
123 * means each set of keys we write is sorted, but the node is not.
124 *
125 * We maintain this log structure in memory - keeping 1Mb of keys sorted would
126 * be expensive, and we have to distinguish between the keys we have written and
127 * the keys we haven't. So to do a lookup in a btree node, we have to search
128 * each sorted set. But we do merge written sets together lazily, so the cost of
129 * these extra searches is quite low (normally most of the keys in a btree node
130 * will be in one big set, and then there'll be one or two sets that are much
131 * smaller).
132 *
133 * This log structure makes bcache's btree more of a hybrid between a
134 * conventional btree and a compacting data structure, with some of the
135 * advantages of both.
136 *
137 * GARBAGE COLLECTION:
138 *
139 * We can't just invalidate any bucket - it might contain dirty data or
140 * metadata. If it once contained dirty data, other writes might overwrite it
141 * later, leaving no valid pointers into that bucket in the index.
142 *
143 * Thus, the primary purpose of garbage collection is to find buckets to reuse.
144 * It also counts how much valid data it each bucket currently contains, so that
145 * allocation can reuse buckets sooner when they've been mostly overwritten.
146 *
147 * It also does some things that are really internal to the btree
148 * implementation. If a btree node contains pointers that are stale by more than
149 * some threshold, it rewrites the btree node to avoid the bucket's generation
150 * wrapping around. It also merges adjacent btree nodes if they're empty enough.
151 *
152 * THE JOURNAL:
153 *
154 * Bcache's journal is not necessary for consistency; we always strictly
155 * order metadata writes so that the btree and everything else is consistent on
156 * disk in the event of an unclean shutdown, and in fact bcache had writeback
157 * caching (with recovery from unclean shutdown) before journalling was
158 * implemented.
159 *
160 * Rather, the journal is purely a performance optimization; we can't complete a
161 * write until we've updated the index on disk, otherwise the cache would be
162 * inconsistent in the event of an unclean shutdown. This means that without the
163 * journal, on random write workloads we constantly have to update all the leaf
164 * nodes in the btree, and those writes will be mostly empty (appending at most
165 * a few keys each) - highly inefficient in terms of amount of metadata writes,
166 * and it puts more strain on the various btree resorting/compacting code.
167 *
168 * The journal is just a log of keys we've inserted; on startup we just reinsert
169 * all the keys in the open journal entries. That means that when we're updating
170 * a node in the btree, we can wait until a 4k block of keys fills up before
171 * writing them out.
172 *
173 * For simplicity, we only journal updates to leaf nodes; updates to parent
174 * nodes are rare enough (since our leaf nodes are huge) that it wasn't worth
175 * the complexity to deal with journalling them (in particular, journal replay)
176 * - updates to non leaf nodes just happen synchronously (see btree_split()).
177 */
178
179 #undef pr_fmt
180 #ifdef __KERNEL__
181 #define pr_fmt(fmt) "bcachefs: %s() " fmt "\n", __func__
182 #else
183 #define pr_fmt(fmt) "%s() " fmt "\n", __func__
184 #endif
185
186 #include <linux/backing-dev-defs.h>
187 #include <linux/bug.h>
188 #include <linux/bio.h>
189 #include <linux/closure.h>
190 #include <linux/kobject.h>
191 #include <linux/list.h>
192 #include <linux/math64.h>
193 #include <linux/mutex.h>
194 #include <linux/percpu-refcount.h>
195 #include <linux/percpu-rwsem.h>
196 #include <linux/refcount.h>
197 #include <linux/rhashtable.h>
198 #include <linux/rwsem.h>
199 #include <linux/semaphore.h>
200 #include <linux/seqlock.h>
201 #include <linux/shrinker.h>
202 #include <linux/srcu.h>
203 #include <linux/types.h>
204 #include <linux/workqueue.h>
205 #include <linux/zstd.h>
206 #include <linux/unicode.h>
207
208 #include "bcachefs_format.h"
209 #include "btree_journal_iter_types.h"
210 #include "disk_accounting_types.h"
211 #include "errcode.h"
212 #include "fifo.h"
213 #include "nocow_locking_types.h"
214 #include "opts.h"
215 #include "recovery_passes_types.h"
216 #include "sb-errors_types.h"
217 #include "seqmutex.h"
218 #include "time_stats.h"
219 #include "util.h"
220
221 #ifdef CONFIG_BCACHEFS_DEBUG
222 #define BCH_WRITE_REF_DEBUG
223 #endif
224
225 #ifndef dynamic_fault
226 #define dynamic_fault(...) 0
227 #endif
228
229 #define race_fault(...) dynamic_fault("bcachefs:race")
230
231 #define count_event(_c, _name) this_cpu_inc((_c)->counters[BCH_COUNTER_##_name])
232
233 #define trace_and_count(_c, _name, ...) \
234 do { \
235 count_event(_c, _name); \
236 trace_##_name(__VA_ARGS__); \
237 } while (0)
238
239 #define bch2_fs_init_fault(name) \
240 dynamic_fault("bcachefs:bch_fs_init:" name)
241 #define bch2_meta_read_fault(name) \
242 dynamic_fault("bcachefs:meta:read:" name)
243 #define bch2_meta_write_fault(name) \
244 dynamic_fault("bcachefs:meta:write:" name)
245
246 #ifdef __KERNEL__
247 #define BCACHEFS_LOG_PREFIX
248 #endif
249
250 #ifdef BCACHEFS_LOG_PREFIX
251
252 #define bch2_log_msg(_c, fmt) "bcachefs (%s): " fmt, ((_c)->name)
253 #define bch2_fmt_dev(_ca, fmt) "bcachefs (%s): " fmt "\n", ((_ca)->name)
254 #define bch2_fmt_dev_offset(_ca, _offset, fmt) "bcachefs (%s sector %llu): " fmt "\n", ((_ca)->name), (_offset)
255 #define bch2_fmt_inum(_c, _inum, fmt) "bcachefs (%s inum %llu): " fmt "\n", ((_c)->name), (_inum)
256 #define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \
257 "bcachefs (%s inum %llu offset %llu): " fmt "\n", ((_c)->name), (_inum), (_offset)
258
259 #else
260
261 #define bch2_log_msg(_c, fmt) fmt
262 #define bch2_fmt_dev(_ca, fmt) "%s: " fmt "\n", ((_ca)->name)
263 #define bch2_fmt_dev_offset(_ca, _offset, fmt) "%s sector %llu: " fmt "\n", ((_ca)->name), (_offset)
264 #define bch2_fmt_inum(_c, _inum, fmt) "inum %llu: " fmt "\n", (_inum)
265 #define bch2_fmt_inum_offset(_c, _inum, _offset, fmt) \
266 "inum %llu offset %llu: " fmt "\n", (_inum), (_offset)
267
268 #endif
269
270 #define bch2_fmt(_c, fmt) bch2_log_msg(_c, fmt "\n")
271
272 void bch2_print_str(struct bch_fs *, const char *);
273
274 __printf(2, 3)
275 void bch2_print_opts(struct bch_opts *, const char *, ...);
276
277 __printf(2, 3)
278 void __bch2_print(struct bch_fs *c, const char *fmt, ...);
279
280 #define maybe_dev_to_fs(_c) _Generic((_c), \
281 struct bch_dev *: ((struct bch_dev *) (_c))->fs, \
282 struct bch_fs *: (_c))
283
284 #define bch2_print(_c, ...) __bch2_print(maybe_dev_to_fs(_c), __VA_ARGS__)
285
286 #define bch2_print_ratelimited(_c, ...) \
287 do { \
288 static DEFINE_RATELIMIT_STATE(_rs, \
289 DEFAULT_RATELIMIT_INTERVAL, \
290 DEFAULT_RATELIMIT_BURST); \
291 \
292 if (__ratelimit(&_rs)) \
293 bch2_print(_c, __VA_ARGS__); \
294 } while (0)
295
296 #define bch_info(c, fmt, ...) \
297 bch2_print(c, KERN_INFO bch2_fmt(c, fmt), ##__VA_ARGS__)
298 #define bch_info_ratelimited(c, fmt, ...) \
299 bch2_print_ratelimited(c, KERN_INFO bch2_fmt(c, fmt), ##__VA_ARGS__)
300 #define bch_notice(c, fmt, ...) \
301 bch2_print(c, KERN_NOTICE bch2_fmt(c, fmt), ##__VA_ARGS__)
302 #define bch_warn(c, fmt, ...) \
303 bch2_print(c, KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__)
304 #define bch_warn_ratelimited(c, fmt, ...) \
305 bch2_print_ratelimited(c, KERN_WARNING bch2_fmt(c, fmt), ##__VA_ARGS__)
306
307 #define bch_err(c, fmt, ...) \
308 bch2_print(c, KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)
309 #define bch_err_dev(ca, fmt, ...) \
310 bch2_print(c, KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__)
311 #define bch_err_dev_offset(ca, _offset, fmt, ...) \
312 bch2_print(c, KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__)
313 #define bch_err_inum(c, _inum, fmt, ...) \
314 bch2_print(c, KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__)
315 #define bch_err_inum_offset(c, _inum, _offset, fmt, ...) \
316 bch2_print(c, KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__)
317
318 #define bch_err_ratelimited(c, fmt, ...) \
319 bch2_print_ratelimited(c, KERN_ERR bch2_fmt(c, fmt), ##__VA_ARGS__)
320 #define bch_err_dev_ratelimited(ca, fmt, ...) \
321 bch2_print_ratelimited(ca, KERN_ERR bch2_fmt_dev(ca, fmt), ##__VA_ARGS__)
322 #define bch_err_dev_offset_ratelimited(ca, _offset, fmt, ...) \
323 bch2_print_ratelimited(ca, KERN_ERR bch2_fmt_dev_offset(ca, _offset, fmt), ##__VA_ARGS__)
324 #define bch_err_inum_ratelimited(c, _inum, fmt, ...) \
325 bch2_print_ratelimited(c, KERN_ERR bch2_fmt_inum(c, _inum, fmt), ##__VA_ARGS__)
326 #define bch_err_inum_offset_ratelimited(c, _inum, _offset, fmt, ...) \
327 bch2_print_ratelimited(c, KERN_ERR bch2_fmt_inum_offset(c, _inum, _offset, fmt), ##__VA_ARGS__)
328
should_print_err(int err)329 static inline bool should_print_err(int err)
330 {
331 return err && !bch2_err_matches(err, BCH_ERR_transaction_restart);
332 }
333
334 #define bch_err_fn(_c, _ret) \
335 do { \
336 if (should_print_err(_ret)) \
337 bch_err(_c, "%s(): error %s", __func__, bch2_err_str(_ret));\
338 } while (0)
339
340 #define bch_err_fn_ratelimited(_c, _ret) \
341 do { \
342 if (should_print_err(_ret)) \
343 bch_err_ratelimited(_c, "%s(): error %s", __func__, bch2_err_str(_ret));\
344 } while (0)
345
346 #define bch_err_msg(_c, _ret, _msg, ...) \
347 do { \
348 if (should_print_err(_ret)) \
349 bch_err(_c, "%s(): error " _msg " %s", __func__, \
350 ##__VA_ARGS__, bch2_err_str(_ret)); \
351 } while (0)
352
353 #define bch_verbose(c, fmt, ...) \
354 do { \
355 if ((c)->opts.verbose) \
356 bch_info(c, fmt, ##__VA_ARGS__); \
357 } while (0)
358
359 #define bch_verbose_ratelimited(c, fmt, ...) \
360 do { \
361 if ((c)->opts.verbose) \
362 bch_info_ratelimited(c, fmt, ##__VA_ARGS__); \
363 } while (0)
364
365 #define pr_verbose_init(opts, fmt, ...) \
366 do { \
367 if (opt_get(opts, verbose)) \
368 pr_info(fmt, ##__VA_ARGS__); \
369 } while (0)
370
371 /* Parameters that are useful for debugging, but should always be compiled in: */
372 #define BCH_DEBUG_PARAMS_ALWAYS() \
373 BCH_DEBUG_PARAM(key_merging_disabled, \
374 "Disables merging of extents") \
375 BCH_DEBUG_PARAM(btree_node_merging_disabled, \
376 "Disables merging of btree nodes") \
377 BCH_DEBUG_PARAM(btree_gc_always_rewrite, \
378 "Causes mark and sweep to compact and rewrite every " \
379 "btree node it traverses") \
380 BCH_DEBUG_PARAM(btree_gc_rewrite_disabled, \
381 "Disables rewriting of btree nodes during mark and sweep")\
382 BCH_DEBUG_PARAM(btree_shrinker_disabled, \
383 "Disables the shrinker callback for the btree node cache")\
384 BCH_DEBUG_PARAM(verify_btree_ondisk, \
385 "Reread btree nodes at various points to verify the " \
386 "mergesort in the read path against modifications " \
387 "done in memory") \
388 BCH_DEBUG_PARAM(verify_all_btree_replicas, \
389 "When reading btree nodes, read all replicas and " \
390 "compare them") \
391 BCH_DEBUG_PARAM(backpointers_no_use_write_buffer, \
392 "Don't use the write buffer for backpointers, enabling "\
393 "extra runtime checks")
394
395 /* Parameters that should only be compiled in debug mode: */
396 #define BCH_DEBUG_PARAMS_DEBUG() \
397 BCH_DEBUG_PARAM(expensive_debug_checks, \
398 "Enables various runtime debugging checks that " \
399 "significantly affect performance") \
400 BCH_DEBUG_PARAM(debug_check_iterators, \
401 "Enables extra verification for btree iterators") \
402 BCH_DEBUG_PARAM(debug_check_btree_accounting, \
403 "Verify btree accounting for keys within a node") \
404 BCH_DEBUG_PARAM(journal_seq_verify, \
405 "Store the journal sequence number in the version " \
406 "number of every btree key, and verify that btree " \
407 "update ordering is preserved during recovery") \
408 BCH_DEBUG_PARAM(inject_invalid_keys, \
409 "Store the journal sequence number in the version " \
410 "number of every btree key, and verify that btree " \
411 "update ordering is preserved during recovery") \
412 BCH_DEBUG_PARAM(test_alloc_startup, \
413 "Force allocator startup to use the slowpath where it" \
414 "can't find enough free buckets without invalidating" \
415 "cached data") \
416 BCH_DEBUG_PARAM(force_reconstruct_read, \
417 "Force reads to use the reconstruct path, when reading" \
418 "from erasure coded extents") \
419 BCH_DEBUG_PARAM(test_restart_gc, \
420 "Test restarting mark and sweep gc when bucket gens change")
421
422 #define BCH_DEBUG_PARAMS_ALL() BCH_DEBUG_PARAMS_ALWAYS() BCH_DEBUG_PARAMS_DEBUG()
423
424 #ifdef CONFIG_BCACHEFS_DEBUG
425 #define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALL()
426 #else
427 #define BCH_DEBUG_PARAMS() BCH_DEBUG_PARAMS_ALWAYS()
428 #endif
429
430 #define BCH_DEBUG_PARAM(name, description) extern bool bch2_##name;
431 BCH_DEBUG_PARAMS()
432 #undef BCH_DEBUG_PARAM
433
434 #ifndef CONFIG_BCACHEFS_DEBUG
435 #define BCH_DEBUG_PARAM(name, description) static const __maybe_unused bool bch2_##name;
436 BCH_DEBUG_PARAMS_DEBUG()
437 #undef BCH_DEBUG_PARAM
438 #endif
439
440 #define BCH_TIME_STATS() \
441 x(btree_node_mem_alloc) \
442 x(btree_node_split) \
443 x(btree_node_compact) \
444 x(btree_node_merge) \
445 x(btree_node_sort) \
446 x(btree_node_read) \
447 x(btree_node_read_done) \
448 x(btree_node_write) \
449 x(btree_interior_update_foreground) \
450 x(btree_interior_update_total) \
451 x(btree_gc) \
452 x(data_write) \
453 x(data_read) \
454 x(data_promote) \
455 x(journal_flush_write) \
456 x(journal_noflush_write) \
457 x(journal_flush_seq) \
458 x(blocked_journal_low_on_space) \
459 x(blocked_journal_low_on_pin) \
460 x(blocked_journal_max_in_flight) \
461 x(blocked_journal_max_open) \
462 x(blocked_key_cache_flush) \
463 x(blocked_allocate) \
464 x(blocked_allocate_open_bucket) \
465 x(blocked_write_buffer_full) \
466 x(nocow_lock_contended)
467
468 enum bch_time_stats {
469 #define x(name) BCH_TIME_##name,
470 BCH_TIME_STATS()
471 #undef x
472 BCH_TIME_STAT_NR
473 };
474
475 #include "alloc_types.h"
476 #include "btree_gc_types.h"
477 #include "btree_types.h"
478 #include "btree_node_scan_types.h"
479 #include "btree_write_buffer_types.h"
480 #include "buckets_types.h"
481 #include "buckets_waiting_for_journal_types.h"
482 #include "clock_types.h"
483 #include "disk_groups_types.h"
484 #include "ec_types.h"
485 #include "journal_types.h"
486 #include "keylist_types.h"
487 #include "quota_types.h"
488 #include "rebalance_types.h"
489 #include "replicas_types.h"
490 #include "sb-members_types.h"
491 #include "subvolume_types.h"
492 #include "super_types.h"
493 #include "thread_with_file_types.h"
494
495 /* Number of nodes btree coalesce will try to coalesce at once */
496 #define GC_MERGE_NODES 4U
497
498 /* Maximum number of nodes we might need to allocate atomically: */
499 #define BTREE_RESERVE_MAX (BTREE_MAX_DEPTH + (BTREE_MAX_DEPTH - 1))
500
501 /* Size of the freelist we allocate btree nodes from: */
502 #define BTREE_NODE_RESERVE (BTREE_RESERVE_MAX * 4)
503
504 #define BTREE_NODE_OPEN_BUCKET_RESERVE (BTREE_RESERVE_MAX * BCH_REPLICAS_MAX)
505
506 struct btree;
507
508 struct io_count {
509 u64 sectors[2][BCH_DATA_NR];
510 };
511
512 struct discard_in_flight {
513 bool in_progress:1;
514 u64 bucket:63;
515 };
516
517 struct bch_dev {
518 struct kobject kobj;
519 #ifdef CONFIG_BCACHEFS_DEBUG
520 atomic_long_t ref;
521 bool dying;
522 unsigned long last_put;
523 #else
524 struct percpu_ref ref;
525 #endif
526 struct completion ref_completion;
527 struct percpu_ref io_ref[2];
528 struct completion io_ref_completion[2];
529
530 struct bch_fs *fs;
531
532 u8 dev_idx;
533 /*
534 * Cached version of this device's member info from superblock
535 * Committed by bch2_write_super() -> bch_fs_mi_update()
536 */
537 struct bch_member_cpu mi;
538 atomic64_t errors[BCH_MEMBER_ERROR_NR];
539 unsigned long write_errors_start;
540
541 __uuid_t uuid;
542 char name[BDEVNAME_SIZE];
543
544 struct bch_sb_handle disk_sb;
545 struct bch_sb *sb_read_scratch;
546 int sb_write_error;
547 dev_t dev;
548 atomic_t flush_seq;
549
550 struct bch_devs_mask self;
551
552 /*
553 * Buckets:
554 * Per-bucket arrays are protected by either rcu_read_lock or
555 * state_lock, for device resize.
556 */
557 GENRADIX(struct bucket) buckets_gc;
558 struct bucket_gens __rcu *bucket_gens;
559 u8 *oldest_gen;
560 unsigned long *buckets_nouse;
561
562 unsigned long *bucket_backpointer_mismatches;
563 unsigned long *bucket_backpointer_empty;
564
565 struct bch_dev_usage_full __percpu
566 *usage;
567
568 /* Allocator: */
569 u64 alloc_cursor[3];
570
571 unsigned nr_open_buckets;
572 unsigned nr_partial_buckets;
573 unsigned nr_btree_reserve;
574
575 size_t inc_gen_needs_gc;
576 size_t inc_gen_really_needs_gc;
577 size_t buckets_waiting_on_journal;
578
579 struct work_struct invalidate_work;
580 struct work_struct discard_work;
581 struct mutex discard_buckets_in_flight_lock;
582 DARRAY(struct discard_in_flight) discard_buckets_in_flight;
583 struct work_struct discard_fast_work;
584
585 atomic64_t rebalance_work;
586
587 struct journal_device journal;
588 u64 prev_journal_sector;
589
590 struct work_struct io_error_work;
591
592 /* The rest of this all shows up in sysfs */
593 atomic64_t cur_latency[2];
594 struct bch2_time_stats_quantiles io_latency[2];
595
596 #define CONGESTED_MAX 1024
597 atomic_t congested;
598 u64 congested_last;
599
600 struct io_count __percpu *io_done;
601 };
602
603 /*
604 * initial_gc_unfixed
605 * error
606 * topology error
607 */
608
609 #define BCH_FS_FLAGS() \
610 x(new_fs) \
611 x(started) \
612 x(clean_recovery) \
613 x(btree_running) \
614 x(accounting_replay_done) \
615 x(may_go_rw) \
616 x(rw) \
617 x(was_rw) \
618 x(stopping) \
619 x(emergency_ro) \
620 x(going_ro) \
621 x(write_disable_complete) \
622 x(clean_shutdown) \
623 x(recovery_running) \
624 x(fsck_running) \
625 x(initial_gc_unfixed) \
626 x(need_delete_dead_snapshots) \
627 x(error) \
628 x(topology_error) \
629 x(errors_fixed) \
630 x(errors_not_fixed) \
631 x(no_invalid_checks) \
632 x(discard_mount_opt_set) \
633
634 enum bch_fs_flags {
635 #define x(n) BCH_FS_##n,
636 BCH_FS_FLAGS()
637 #undef x
638 };
639
640 struct btree_debug {
641 unsigned id;
642 };
643
644 #define BCH_TRANSACTIONS_NR 128
645
646 struct btree_transaction_stats {
647 struct bch2_time_stats duration;
648 struct bch2_time_stats lock_hold_times;
649 struct mutex lock;
650 unsigned nr_max_paths;
651 unsigned journal_entries_size;
652 unsigned max_mem;
653 char *max_paths_text;
654 };
655
656 struct bch_fs_pcpu {
657 u64 sectors_available;
658 };
659
660 struct journal_seq_blacklist_table {
661 size_t nr;
662 struct journal_seq_blacklist_table_entry {
663 u64 start;
664 u64 end;
665 bool dirty;
666 } entries[];
667 };
668
669 struct btree_trans_buf {
670 struct btree_trans *trans;
671 };
672
673 #define BCACHEFS_ROOT_SUBVOL_INUM \
674 ((subvol_inum) { BCACHEFS_ROOT_SUBVOL, BCACHEFS_ROOT_INO })
675
676 #define BCH_WRITE_REFS() \
677 x(journal) \
678 x(trans) \
679 x(write) \
680 x(promote) \
681 x(node_rewrite) \
682 x(stripe_create) \
683 x(stripe_delete) \
684 x(reflink) \
685 x(fallocate) \
686 x(fsync) \
687 x(dio_write) \
688 x(discard) \
689 x(discard_fast) \
690 x(check_discard_freespace_key) \
691 x(invalidate) \
692 x(delete_dead_snapshots) \
693 x(gc_gens) \
694 x(snapshot_delete_pagecache) \
695 x(sysfs) \
696 x(btree_write_buffer) \
697 x(btree_node_scrub)
698
699 enum bch_write_ref {
700 #define x(n) BCH_WRITE_REF_##n,
701 BCH_WRITE_REFS()
702 #undef x
703 BCH_WRITE_REF_NR,
704 };
705
706 #define BCH_FS_DEFAULT_UTF8_ENCODING UNICODE_AGE(12, 1, 0)
707
708 struct bch_fs {
709 struct closure cl;
710
711 struct list_head list;
712 struct kobject kobj;
713 struct kobject counters_kobj;
714 struct kobject internal;
715 struct kobject opts_dir;
716 struct kobject time_stats;
717 unsigned long flags;
718
719 int minor;
720 struct device *chardev;
721 struct super_block *vfs_sb;
722 dev_t dev;
723 char name[40];
724 struct stdio_redirect *stdio;
725 struct task_struct *stdio_filter;
726
727 /* ro/rw, add/remove/resize devices: */
728 struct rw_semaphore state_lock;
729
730 /* Counts outstanding writes, for clean transition to read-only */
731 #ifdef BCH_WRITE_REF_DEBUG
732 atomic_long_t writes[BCH_WRITE_REF_NR];
733 #else
734 struct percpu_ref writes;
735 #endif
736 /*
737 * Certain operations are only allowed in single threaded mode, during
738 * recovery, and we want to assert that this is the case:
739 */
740 struct task_struct *recovery_task;
741
742 /*
743 * Analagous to c->writes, for asynchronous ops that don't necessarily
744 * need fs to be read-write
745 */
746 refcount_t ro_ref;
747 wait_queue_head_t ro_ref_wait;
748
749 struct work_struct read_only_work;
750
751 struct bch_dev __rcu *devs[BCH_SB_MEMBERS_MAX];
752
753 struct bch_accounting_mem accounting;
754
755 struct bch_replicas_cpu replicas;
756 struct bch_replicas_cpu replicas_gc;
757 struct mutex replicas_gc_lock;
758
759 struct journal_entry_res btree_root_journal_res;
760 struct journal_entry_res clock_journal_res;
761
762 struct bch_disk_groups_cpu __rcu *disk_groups;
763
764 struct bch_opts opts;
765
766 /* Updated by bch2_sb_update():*/
767 struct {
768 __uuid_t uuid;
769 __uuid_t user_uuid;
770
771 u16 version;
772 u16 version_incompat;
773 u16 version_incompat_allowed;
774 u16 version_min;
775 u16 version_upgrade_complete;
776
777 u8 nr_devices;
778 u8 clean;
779
780 u8 encryption_type;
781
782 u64 time_base_lo;
783 u32 time_base_hi;
784 unsigned time_units_per_sec;
785 unsigned nsec_per_time_unit;
786 u64 features;
787 u64 compat;
788 unsigned long errors_silent[BITS_TO_LONGS(BCH_FSCK_ERR_MAX)];
789 u64 btrees_lost_data;
790 } sb;
791 DARRAY(enum bcachefs_metadata_version)
792 incompat_versions_requested;
793
794 #ifdef CONFIG_UNICODE
795 struct unicode_map *cf_encoding;
796 #endif
797
798 struct bch_sb_handle disk_sb;
799
800 unsigned short block_bits; /* ilog2(block_size) */
801
802 u16 btree_foreground_merge_threshold;
803
804 struct closure sb_write;
805 struct mutex sb_lock;
806
807 /* snapshot.c: */
808 struct snapshot_table __rcu *snapshots;
809 struct mutex snapshot_table_lock;
810 struct rw_semaphore snapshot_create_lock;
811
812 struct work_struct snapshot_delete_work;
813 struct work_struct snapshot_wait_for_pagecache_and_delete_work;
814 snapshot_id_list snapshots_unlinked;
815 struct mutex snapshots_unlinked_lock;
816
817 /* BTREE CACHE */
818 struct bio_set btree_bio;
819 struct workqueue_struct *btree_read_complete_wq;
820 struct workqueue_struct *btree_write_submit_wq;
821
822 struct btree_root btree_roots_known[BTREE_ID_NR];
823 DARRAY(struct btree_root) btree_roots_extra;
824 struct mutex btree_root_lock;
825
826 struct btree_cache btree_cache;
827
828 /*
829 * Cache of allocated btree nodes - if we allocate a btree node and
830 * don't use it, if we free it that space can't be reused until going
831 * _all_ the way through the allocator (which exposes us to a livelock
832 * when allocating btree reserves fail halfway through) - instead, we
833 * can stick them here:
834 */
835 struct btree_alloc btree_reserve_cache[BTREE_NODE_RESERVE * 2];
836 unsigned btree_reserve_cache_nr;
837 struct mutex btree_reserve_cache_lock;
838
839 mempool_t btree_interior_update_pool;
840 struct list_head btree_interior_update_list;
841 struct list_head btree_interior_updates_unwritten;
842 struct mutex btree_interior_update_lock;
843 struct closure_waitlist btree_interior_update_wait;
844
845 struct workqueue_struct *btree_interior_update_worker;
846 struct work_struct btree_interior_update_work;
847
848 struct workqueue_struct *btree_node_rewrite_worker;
849 struct list_head btree_node_rewrites;
850 struct list_head btree_node_rewrites_pending;
851 spinlock_t btree_node_rewrites_lock;
852 struct closure_waitlist btree_node_rewrites_wait;
853
854 /* btree_io.c: */
855 spinlock_t btree_write_error_lock;
856 struct btree_write_stats {
857 atomic64_t nr;
858 atomic64_t bytes;
859 } btree_write_stats[BTREE_WRITE_TYPE_NR];
860
861 /* btree_iter.c: */
862 struct seqmutex btree_trans_lock;
863 struct list_head btree_trans_list;
864 mempool_t btree_trans_pool;
865 mempool_t btree_trans_mem_pool;
866 struct btree_trans_buf __percpu *btree_trans_bufs;
867
868 struct srcu_struct btree_trans_barrier;
869 bool btree_trans_barrier_initialized;
870
871 struct btree_key_cache btree_key_cache;
872 unsigned btree_key_cache_btrees;
873
874 struct btree_write_buffer btree_write_buffer;
875
876 struct workqueue_struct *btree_update_wq;
877 struct workqueue_struct *btree_io_complete_wq;
878 /* copygc needs its own workqueue for index updates.. */
879 struct workqueue_struct *copygc_wq;
880 /*
881 * Use a dedicated wq for write ref holder tasks. Required to avoid
882 * dependency problems with other wq tasks that can block on ref
883 * draining, such as read-only transition.
884 */
885 struct workqueue_struct *write_ref_wq;
886
887 /* ALLOCATION */
888 struct bch_devs_mask rw_devs[BCH_DATA_NR];
889 unsigned long rw_devs_change_count;
890
891 u64 capacity; /* sectors */
892 u64 reserved; /* sectors */
893
894 /*
895 * When capacity _decreases_ (due to a disk being removed), we
896 * increment capacity_gen - this invalidates outstanding reservations
897 * and forces them to be revalidated
898 */
899 u32 capacity_gen;
900 unsigned bucket_size_max;
901
902 atomic64_t sectors_available;
903 struct mutex sectors_available_lock;
904
905 struct bch_fs_pcpu __percpu *pcpu;
906
907 struct percpu_rw_semaphore mark_lock;
908
909 seqcount_t usage_lock;
910 struct bch_fs_usage_base __percpu *usage;
911 u64 __percpu *online_reserved;
912
913 unsigned long allocator_last_stuck;
914
915 struct io_clock io_clock[2];
916
917 /* JOURNAL SEQ BLACKLIST */
918 struct journal_seq_blacklist_table *
919 journal_seq_blacklist_table;
920
921 /* ALLOCATOR */
922 spinlock_t freelist_lock;
923 struct closure_waitlist freelist_wait;
924
925 open_bucket_idx_t open_buckets_freelist;
926 open_bucket_idx_t open_buckets_nr_free;
927 struct closure_waitlist open_buckets_wait;
928 struct open_bucket open_buckets[OPEN_BUCKETS_COUNT];
929 open_bucket_idx_t open_buckets_hash[OPEN_BUCKETS_COUNT];
930
931 open_bucket_idx_t open_buckets_partial[OPEN_BUCKETS_COUNT];
932 open_bucket_idx_t open_buckets_partial_nr;
933
934 struct write_point btree_write_point;
935 struct write_point rebalance_write_point;
936
937 struct write_point write_points[WRITE_POINT_MAX];
938 struct hlist_head write_points_hash[WRITE_POINT_HASH_NR];
939 struct mutex write_points_hash_lock;
940 unsigned write_points_nr;
941
942 struct buckets_waiting_for_journal buckets_waiting_for_journal;
943
944 /* GARBAGE COLLECTION */
945 struct work_struct gc_gens_work;
946 unsigned long gc_count;
947
948 enum btree_id gc_gens_btree;
949 struct bpos gc_gens_pos;
950
951 /*
952 * Tracks GC's progress - everything in the range [ZERO_KEY..gc_cur_pos]
953 * has been marked by GC.
954 *
955 * gc_cur_phase is a superset of btree_ids (BTREE_ID_extents etc.)
956 *
957 * Protected by gc_pos_lock. Only written to by GC thread, so GC thread
958 * can read without a lock.
959 */
960 seqcount_t gc_pos_lock;
961 struct gc_pos gc_pos;
962
963 /*
964 * The allocation code needs gc_mark in struct bucket to be correct, but
965 * it's not while a gc is in progress.
966 */
967 struct rw_semaphore gc_lock;
968 struct mutex gc_gens_lock;
969
970 /* IO PATH */
971 struct semaphore io_in_flight;
972 struct bio_set bio_read;
973 struct bio_set bio_read_split;
974 struct bio_set bio_write;
975 struct bio_set replica_set;
976 struct mutex bio_bounce_pages_lock;
977 mempool_t bio_bounce_pages;
978 struct bucket_nocow_lock_table
979 nocow_locks;
980 struct rhashtable promote_table;
981
982 mempool_t compression_bounce[2];
983 mempool_t compress_workspace[BCH_COMPRESSION_OPT_NR];
984 size_t zstd_workspace_size;
985
986 struct bch_key chacha20_key;
987 bool chacha20_key_set;
988
989 atomic64_t key_version;
990
991 mempool_t large_bkey_pool;
992
993 /* MOVE.C */
994 struct list_head moving_context_list;
995 struct mutex moving_context_lock;
996
997 /* REBALANCE */
998 struct bch_fs_rebalance rebalance;
999
1000 /* COPYGC */
1001 struct task_struct *copygc_thread;
1002 struct write_point copygc_write_point;
1003 s64 copygc_wait_at;
1004 s64 copygc_wait;
1005 bool copygc_running;
1006 wait_queue_head_t copygc_running_wq;
1007
1008 /* STRIPES: */
1009 GENRADIX(struct gc_stripe) gc_stripes;
1010
1011 struct hlist_head ec_stripes_new[32];
1012 spinlock_t ec_stripes_new_lock;
1013
1014 /* ERASURE CODING */
1015 struct list_head ec_stripe_head_list;
1016 struct mutex ec_stripe_head_lock;
1017
1018 struct list_head ec_stripe_new_list;
1019 struct mutex ec_stripe_new_lock;
1020 wait_queue_head_t ec_stripe_new_wait;
1021
1022 struct work_struct ec_stripe_create_work;
1023 u64 ec_stripe_hint;
1024
1025 struct work_struct ec_stripe_delete_work;
1026
1027 struct bio_set ec_bioset;
1028
1029 /* REFLINK */
1030 reflink_gc_table reflink_gc_table;
1031 size_t reflink_gc_nr;
1032
1033 /* fs.c */
1034 struct list_head vfs_inodes_list;
1035 struct mutex vfs_inodes_lock;
1036 struct rhashtable vfs_inodes_table;
1037 struct rhltable vfs_inodes_by_inum_table;
1038
1039 /* VFS IO PATH - fs-io.c */
1040 struct bio_set writepage_bioset;
1041 struct bio_set dio_write_bioset;
1042 struct bio_set dio_read_bioset;
1043 struct bio_set nocow_flush_bioset;
1044
1045 /* QUOTAS */
1046 struct bch_memquota_type quotas[QTYP_NR];
1047
1048 /* RECOVERY */
1049 u64 journal_replay_seq_start;
1050 u64 journal_replay_seq_end;
1051 /*
1052 * Two different uses:
1053 * "Has this fsck pass?" - i.e. should this type of error be an
1054 * emergency read-only
1055 * And, in certain situations fsck will rewind to an earlier pass: used
1056 * for signaling to the toplevel code which pass we want to run now.
1057 */
1058 enum bch_recovery_pass curr_recovery_pass;
1059 enum bch_recovery_pass next_recovery_pass;
1060 /* bitmask of recovery passes that we actually ran */
1061 u64 recovery_passes_complete;
1062 /* never rewinds version of curr_recovery_pass */
1063 enum bch_recovery_pass recovery_pass_done;
1064 spinlock_t recovery_pass_lock;
1065 struct semaphore online_fsck_mutex;
1066
1067 /* DEBUG JUNK */
1068 struct dentry *fs_debug_dir;
1069 struct dentry *btree_debug_dir;
1070 struct btree_debug btree_debug[BTREE_ID_NR];
1071 struct btree *verify_data;
1072 struct btree_node *verify_ondisk;
1073 struct mutex verify_lock;
1074
1075 /*
1076 * A btree node on disk could have too many bsets for an iterator to fit
1077 * on the stack - have to dynamically allocate them
1078 */
1079 mempool_t fill_iter;
1080
1081 mempool_t btree_bounce_pool;
1082
1083 struct journal journal;
1084 GENRADIX(struct journal_replay *) journal_entries;
1085 u64 journal_entries_base_seq;
1086 struct journal_keys journal_keys;
1087 struct list_head journal_iters;
1088
1089 struct find_btree_nodes found_btree_nodes;
1090
1091 u64 last_bucket_seq_cleanup;
1092
1093 u64 counters_on_mount[BCH_COUNTER_NR];
1094 u64 __percpu *counters;
1095
1096 struct bch2_time_stats times[BCH_TIME_STAT_NR];
1097
1098 struct btree_transaction_stats btree_transaction_stats[BCH_TRANSACTIONS_NR];
1099
1100 /* ERRORS */
1101 struct list_head fsck_error_msgs;
1102 struct mutex fsck_error_msgs_lock;
1103 bool fsck_alloc_msgs_err;
1104
1105 bch_sb_errors_cpu fsck_error_counts;
1106 struct mutex fsck_error_counts_lock;
1107 };
1108
1109 extern struct wait_queue_head bch2_read_only_wait;
1110
bch2_write_ref_get(struct bch_fs * c,enum bch_write_ref ref)1111 static inline void bch2_write_ref_get(struct bch_fs *c, enum bch_write_ref ref)
1112 {
1113 #ifdef BCH_WRITE_REF_DEBUG
1114 atomic_long_inc(&c->writes[ref]);
1115 #else
1116 percpu_ref_get(&c->writes);
1117 #endif
1118 }
1119
__bch2_write_ref_tryget(struct bch_fs * c,enum bch_write_ref ref)1120 static inline bool __bch2_write_ref_tryget(struct bch_fs *c, enum bch_write_ref ref)
1121 {
1122 #ifdef BCH_WRITE_REF_DEBUG
1123 return !test_bit(BCH_FS_going_ro, &c->flags) &&
1124 atomic_long_inc_not_zero(&c->writes[ref]);
1125 #else
1126 return percpu_ref_tryget(&c->writes);
1127 #endif
1128 }
1129
bch2_write_ref_tryget(struct bch_fs * c,enum bch_write_ref ref)1130 static inline bool bch2_write_ref_tryget(struct bch_fs *c, enum bch_write_ref ref)
1131 {
1132 #ifdef BCH_WRITE_REF_DEBUG
1133 return !test_bit(BCH_FS_going_ro, &c->flags) &&
1134 atomic_long_inc_not_zero(&c->writes[ref]);
1135 #else
1136 return percpu_ref_tryget_live(&c->writes);
1137 #endif
1138 }
1139
bch2_write_ref_put(struct bch_fs * c,enum bch_write_ref ref)1140 static inline void bch2_write_ref_put(struct bch_fs *c, enum bch_write_ref ref)
1141 {
1142 #ifdef BCH_WRITE_REF_DEBUG
1143 long v = atomic_long_dec_return(&c->writes[ref]);
1144
1145 BUG_ON(v < 0);
1146 if (v)
1147 return;
1148 for (unsigned i = 0; i < BCH_WRITE_REF_NR; i++)
1149 if (atomic_long_read(&c->writes[i]))
1150 return;
1151
1152 set_bit(BCH_FS_write_disable_complete, &c->flags);
1153 wake_up(&bch2_read_only_wait);
1154 #else
1155 percpu_ref_put(&c->writes);
1156 #endif
1157 }
1158
bch2_ro_ref_tryget(struct bch_fs * c)1159 static inline bool bch2_ro_ref_tryget(struct bch_fs *c)
1160 {
1161 if (test_bit(BCH_FS_stopping, &c->flags))
1162 return false;
1163
1164 return refcount_inc_not_zero(&c->ro_ref);
1165 }
1166
bch2_ro_ref_put(struct bch_fs * c)1167 static inline void bch2_ro_ref_put(struct bch_fs *c)
1168 {
1169 if (refcount_dec_and_test(&c->ro_ref))
1170 wake_up(&c->ro_ref_wait);
1171 }
1172
bch2_set_ra_pages(struct bch_fs * c,unsigned ra_pages)1173 static inline void bch2_set_ra_pages(struct bch_fs *c, unsigned ra_pages)
1174 {
1175 #ifndef NO_BCACHEFS_FS
1176 if (c->vfs_sb)
1177 c->vfs_sb->s_bdi->ra_pages = ra_pages;
1178 #endif
1179 }
1180
bucket_bytes(const struct bch_dev * ca)1181 static inline unsigned bucket_bytes(const struct bch_dev *ca)
1182 {
1183 return ca->mi.bucket_size << 9;
1184 }
1185
block_bytes(const struct bch_fs * c)1186 static inline unsigned block_bytes(const struct bch_fs *c)
1187 {
1188 return c->opts.block_size;
1189 }
1190
block_sectors(const struct bch_fs * c)1191 static inline unsigned block_sectors(const struct bch_fs *c)
1192 {
1193 return c->opts.block_size >> 9;
1194 }
1195
btree_id_cached(const struct bch_fs * c,enum btree_id btree)1196 static inline bool btree_id_cached(const struct bch_fs *c, enum btree_id btree)
1197 {
1198 return c->btree_key_cache_btrees & (1U << btree);
1199 }
1200
bch2_time_to_timespec(const struct bch_fs * c,s64 time)1201 static inline struct timespec64 bch2_time_to_timespec(const struct bch_fs *c, s64 time)
1202 {
1203 struct timespec64 t;
1204 s64 sec;
1205 s32 rem;
1206
1207 time += c->sb.time_base_lo;
1208
1209 sec = div_s64_rem(time, c->sb.time_units_per_sec, &rem);
1210
1211 set_normalized_timespec64(&t, sec, rem * (s64)c->sb.nsec_per_time_unit);
1212
1213 return t;
1214 }
1215
timespec_to_bch2_time(const struct bch_fs * c,struct timespec64 ts)1216 static inline s64 timespec_to_bch2_time(const struct bch_fs *c, struct timespec64 ts)
1217 {
1218 return (ts.tv_sec * c->sb.time_units_per_sec +
1219 (int) ts.tv_nsec / c->sb.nsec_per_time_unit) - c->sb.time_base_lo;
1220 }
1221
bch2_current_time(const struct bch_fs * c)1222 static inline s64 bch2_current_time(const struct bch_fs *c)
1223 {
1224 struct timespec64 now;
1225
1226 ktime_get_coarse_real_ts64(&now);
1227 return timespec_to_bch2_time(c, now);
1228 }
1229
bch2_current_io_time(const struct bch_fs * c,int rw)1230 static inline u64 bch2_current_io_time(const struct bch_fs *c, int rw)
1231 {
1232 return max(1ULL, (u64) atomic64_read(&c->io_clock[rw].now) & LRU_TIME_MAX);
1233 }
1234
bch2_fs_stdio_redirect(struct bch_fs * c)1235 static inline struct stdio_redirect *bch2_fs_stdio_redirect(struct bch_fs *c)
1236 {
1237 struct stdio_redirect *stdio = c->stdio;
1238
1239 if (c->stdio_filter && c->stdio_filter != current)
1240 stdio = NULL;
1241 return stdio;
1242 }
1243
metadata_replicas_required(struct bch_fs * c)1244 static inline unsigned metadata_replicas_required(struct bch_fs *c)
1245 {
1246 return min(c->opts.metadata_replicas,
1247 c->opts.metadata_replicas_required);
1248 }
1249
data_replicas_required(struct bch_fs * c)1250 static inline unsigned data_replicas_required(struct bch_fs *c)
1251 {
1252 return min(c->opts.data_replicas,
1253 c->opts.data_replicas_required);
1254 }
1255
1256 #define BKEY_PADDED_ONSTACK(key, pad) \
1257 struct { struct bkey_i key; __u64 key ## _pad[pad]; }
1258
1259 #endif /* _BCACHEFS_H */
1260