1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2015 Shaohua Li <shli@fb.com> |
4 | * Copyright (C) 2016 Song Liu <songliubraving@fb.com> |
5 | */ |
6 | #include <linux/kernel.h> |
7 | #include <linux/wait.h> |
8 | #include <linux/blkdev.h> |
9 | #include <linux/slab.h> |
10 | #include <linux/raid/md_p.h> |
11 | #include <linux/crc32c.h> |
12 | #include <linux/random.h> |
13 | #include <linux/kthread.h> |
14 | #include <linux/types.h> |
15 | #include "md.h" |
16 | #include "raid5.h" |
17 | #include "md-bitmap.h" |
18 | #include "raid5-log.h" |
19 | |
20 | /* |
21 | * metadata/data stored in disk with 4k size unit (a block) regardless |
22 | * underneath hardware sector size. only works with PAGE_SIZE == 4096 |
23 | */ |
24 | #define BLOCK_SECTORS (8) |
25 | #define BLOCK_SECTOR_SHIFT (3) |
26 | |
27 | /* |
28 | * log->max_free_space is min(1/4 disk size, 10G reclaimable space). |
29 | * |
30 | * In write through mode, the reclaim runs every log->max_free_space. |
31 | * This can prevent the recovery scans for too long |
32 | */ |
33 | #define RECLAIM_MAX_FREE_SPACE (10 * 1024 * 1024 * 2) /* sector */ |
34 | #define RECLAIM_MAX_FREE_SPACE_SHIFT (2) |
35 | |
36 | /* wake up reclaim thread periodically */ |
37 | #define R5C_RECLAIM_WAKEUP_INTERVAL (30 * HZ) |
38 | /* start flush with these full stripes */ |
39 | #define R5C_FULL_STRIPE_FLUSH_BATCH(conf) (conf->max_nr_stripes / 4) |
40 | /* reclaim stripes in groups */ |
41 | #define R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2) |
42 | |
43 | /* |
44 | * We only need 2 bios per I/O unit to make progress, but ensure we |
45 | * have a few more available to not get too tight. |
46 | */ |
47 | #define R5L_POOL_SIZE 4 |
48 | |
49 | static char *r5c_journal_mode_str[] = {"write-through" , |
50 | "write-back" }; |
51 | /* |
52 | * raid5 cache state machine |
53 | * |
54 | * With the RAID cache, each stripe works in two phases: |
55 | * - caching phase |
56 | * - writing-out phase |
57 | * |
58 | * These two phases are controlled by bit STRIPE_R5C_CACHING: |
59 | * if STRIPE_R5C_CACHING == 0, the stripe is in writing-out phase |
60 | * if STRIPE_R5C_CACHING == 1, the stripe is in caching phase |
61 | * |
62 | * When there is no journal, or the journal is in write-through mode, |
63 | * the stripe is always in writing-out phase. |
64 | * |
65 | * For write-back journal, the stripe is sent to caching phase on write |
66 | * (r5c_try_caching_write). r5c_make_stripe_write_out() kicks off |
67 | * the write-out phase by clearing STRIPE_R5C_CACHING. |
68 | * |
69 | * Stripes in caching phase do not write the raid disks. Instead, all |
70 | * writes are committed from the log device. Therefore, a stripe in |
71 | * caching phase handles writes as: |
72 | * - write to log device |
73 | * - return IO |
74 | * |
75 | * Stripes in writing-out phase handle writes as: |
76 | * - calculate parity |
77 | * - write pending data and parity to journal |
78 | * - write data and parity to raid disks |
79 | * - return IO for pending writes |
80 | */ |
81 | |
82 | struct r5l_log { |
83 | struct md_rdev *rdev; |
84 | |
85 | u32 uuid_checksum; |
86 | |
87 | sector_t device_size; /* log device size, round to |
88 | * BLOCK_SECTORS */ |
89 | sector_t max_free_space; /* reclaim run if free space is at |
90 | * this size */ |
91 | |
92 | sector_t last_checkpoint; /* log tail. where recovery scan |
93 | * starts from */ |
94 | u64 last_cp_seq; /* log tail sequence */ |
95 | |
96 | sector_t log_start; /* log head. where new data appends */ |
97 | u64 seq; /* log head sequence */ |
98 | |
99 | sector_t next_checkpoint; |
100 | |
101 | struct mutex io_mutex; |
102 | struct r5l_io_unit *current_io; /* current io_unit accepting new data */ |
103 | |
104 | spinlock_t io_list_lock; |
105 | struct list_head running_ios; /* io_units which are still running, |
106 | * and have not yet been completely |
107 | * written to the log */ |
108 | struct list_head io_end_ios; /* io_units which have been completely |
109 | * written to the log but not yet written |
110 | * to the RAID */ |
111 | struct list_head flushing_ios; /* io_units which are waiting for log |
112 | * cache flush */ |
113 | struct list_head finished_ios; /* io_units which settle down in log disk */ |
114 | struct bio flush_bio; |
115 | |
116 | struct list_head no_mem_stripes; /* pending stripes, -ENOMEM */ |
117 | |
118 | struct kmem_cache *io_kc; |
119 | mempool_t io_pool; |
120 | struct bio_set bs; |
121 | mempool_t meta_pool; |
122 | |
123 | struct md_thread __rcu *reclaim_thread; |
124 | unsigned long reclaim_target; /* number of space that need to be |
125 | * reclaimed. if it's 0, reclaim spaces |
126 | * used by io_units which are in |
127 | * IO_UNIT_STRIPE_END state (eg, reclaim |
128 | * doesn't wait for specific io_unit |
129 | * switching to IO_UNIT_STRIPE_END |
130 | * state) */ |
131 | wait_queue_head_t iounit_wait; |
132 | |
133 | struct list_head no_space_stripes; /* pending stripes, log has no space */ |
134 | spinlock_t no_space_stripes_lock; |
135 | |
136 | bool need_cache_flush; |
137 | |
138 | /* for r5c_cache */ |
139 | enum r5c_journal_mode r5c_journal_mode; |
140 | |
141 | /* all stripes in r5cache, in the order of seq at sh->log_start */ |
142 | struct list_head stripe_in_journal_list; |
143 | |
144 | spinlock_t stripe_in_journal_lock; |
145 | atomic_t stripe_in_journal_count; |
146 | |
147 | /* to submit async io_units, to fulfill ordering of flush */ |
148 | struct work_struct deferred_io_work; |
149 | /* to disable write back during in degraded mode */ |
150 | struct work_struct disable_writeback_work; |
151 | |
152 | /* to for chunk_aligned_read in writeback mode, details below */ |
153 | spinlock_t tree_lock; |
154 | struct radix_tree_root big_stripe_tree; |
155 | }; |
156 | |
157 | /* |
158 | * Enable chunk_aligned_read() with write back cache. |
159 | * |
160 | * Each chunk may contain more than one stripe (for example, a 256kB |
161 | * chunk contains 64 4kB-page, so this chunk contain 64 stripes). For |
162 | * chunk_aligned_read, these stripes are grouped into one "big_stripe". |
163 | * For each big_stripe, we count how many stripes of this big_stripe |
164 | * are in the write back cache. These data are tracked in a radix tree |
165 | * (big_stripe_tree). We use radix_tree item pointer as the counter. |
166 | * r5c_tree_index() is used to calculate keys for the radix tree. |
167 | * |
168 | * chunk_aligned_read() calls r5c_big_stripe_cached() to look up |
169 | * big_stripe of each chunk in the tree. If this big_stripe is in the |
170 | * tree, chunk_aligned_read() aborts. This look up is protected by |
171 | * rcu_read_lock(). |
172 | * |
173 | * It is necessary to remember whether a stripe is counted in |
174 | * big_stripe_tree. Instead of adding new flag, we reuses existing flags: |
175 | * STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE. If either of these |
176 | * two flags are set, the stripe is counted in big_stripe_tree. This |
177 | * requires moving set_bit(STRIPE_R5C_PARTIAL_STRIPE) to |
178 | * r5c_try_caching_write(); and moving clear_bit of |
179 | * STRIPE_R5C_PARTIAL_STRIPE and STRIPE_R5C_FULL_STRIPE to |
180 | * r5c_finish_stripe_write_out(). |
181 | */ |
182 | |
183 | /* |
184 | * radix tree requests lowest 2 bits of data pointer to be 2b'00. |
185 | * So it is necessary to left shift the counter by 2 bits before using it |
186 | * as data pointer of the tree. |
187 | */ |
188 | #define R5C_RADIX_COUNT_SHIFT 2 |
189 | |
190 | /* |
191 | * calculate key for big_stripe_tree |
192 | * |
193 | * sect: align_bi->bi_iter.bi_sector or sh->sector |
194 | */ |
195 | static inline sector_t r5c_tree_index(struct r5conf *conf, |
196 | sector_t sect) |
197 | { |
198 | sector_div(sect, conf->chunk_sectors); |
199 | return sect; |
200 | } |
201 | |
202 | /* |
203 | * an IO range starts from a meta data block and end at the next meta data |
204 | * block. The io unit's the meta data block tracks data/parity followed it. io |
205 | * unit is written to log disk with normal write, as we always flush log disk |
206 | * first and then start move data to raid disks, there is no requirement to |
207 | * write io unit with FLUSH/FUA |
208 | */ |
209 | struct r5l_io_unit { |
210 | struct r5l_log *log; |
211 | |
212 | struct page *meta_page; /* store meta block */ |
213 | int meta_offset; /* current offset in meta_page */ |
214 | |
215 | struct bio *current_bio;/* current_bio accepting new data */ |
216 | |
217 | atomic_t pending_stripe;/* how many stripes not flushed to raid */ |
218 | u64 seq; /* seq number of the metablock */ |
219 | sector_t log_start; /* where the io_unit starts */ |
220 | sector_t log_end; /* where the io_unit ends */ |
221 | struct list_head log_sibling; /* log->running_ios */ |
222 | struct list_head stripe_list; /* stripes added to the io_unit */ |
223 | |
224 | int state; |
225 | bool need_split_bio; |
226 | struct bio *split_bio; |
227 | |
228 | unsigned int has_flush:1; /* include flush request */ |
229 | unsigned int has_fua:1; /* include fua request */ |
230 | unsigned int has_null_flush:1; /* include null flush request */ |
231 | unsigned int has_flush_payload:1; /* include flush payload */ |
232 | /* |
233 | * io isn't sent yet, flush/fua request can only be submitted till it's |
234 | * the first IO in running_ios list |
235 | */ |
236 | unsigned int io_deferred:1; |
237 | |
238 | struct bio_list flush_barriers; /* size == 0 flush bios */ |
239 | }; |
240 | |
241 | /* r5l_io_unit state */ |
242 | enum r5l_io_unit_state { |
243 | IO_UNIT_RUNNING = 0, /* accepting new IO */ |
244 | IO_UNIT_IO_START = 1, /* io_unit bio start writing to log, |
245 | * don't accepting new bio */ |
246 | IO_UNIT_IO_END = 2, /* io_unit bio finish writing to log */ |
247 | IO_UNIT_STRIPE_END = 3, /* stripes data finished writing to raid */ |
248 | }; |
249 | |
250 | bool r5c_is_writeback(struct r5l_log *log) |
251 | { |
252 | return (log != NULL && |
253 | log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK); |
254 | } |
255 | |
256 | static sector_t r5l_ring_add(struct r5l_log *log, sector_t start, sector_t inc) |
257 | { |
258 | start += inc; |
259 | if (start >= log->device_size) |
260 | start = start - log->device_size; |
261 | return start; |
262 | } |
263 | |
264 | static sector_t r5l_ring_distance(struct r5l_log *log, sector_t start, |
265 | sector_t end) |
266 | { |
267 | if (end >= start) |
268 | return end - start; |
269 | else |
270 | return end + log->device_size - start; |
271 | } |
272 | |
273 | static bool r5l_has_free_space(struct r5l_log *log, sector_t size) |
274 | { |
275 | sector_t used_size; |
276 | |
277 | used_size = r5l_ring_distance(log, start: log->last_checkpoint, |
278 | end: log->log_start); |
279 | |
280 | return log->device_size > used_size + size; |
281 | } |
282 | |
283 | static void __r5l_set_io_unit_state(struct r5l_io_unit *io, |
284 | enum r5l_io_unit_state state) |
285 | { |
286 | if (WARN_ON(io->state >= state)) |
287 | return; |
288 | io->state = state; |
289 | } |
290 | |
291 | static void |
292 | r5c_return_dev_pending_writes(struct r5conf *conf, struct r5dev *dev) |
293 | { |
294 | struct bio *wbi, *wbi2; |
295 | |
296 | wbi = dev->written; |
297 | dev->written = NULL; |
298 | while (wbi && wbi->bi_iter.bi_sector < |
299 | dev->sector + RAID5_STRIPE_SECTORS(conf)) { |
300 | wbi2 = r5_next_bio(conf, bio: wbi, sector: dev->sector); |
301 | md_write_end(mddev: conf->mddev); |
302 | bio_endio(wbi); |
303 | wbi = wbi2; |
304 | } |
305 | } |
306 | |
307 | void r5c_handle_cached_data_endio(struct r5conf *conf, |
308 | struct stripe_head *sh, int disks) |
309 | { |
310 | int i; |
311 | |
312 | for (i = sh->disks; i--; ) { |
313 | if (sh->dev[i].written) { |
314 | set_bit(nr: R5_UPTODATE, addr: &sh->dev[i].flags); |
315 | r5c_return_dev_pending_writes(conf, dev: &sh->dev[i]); |
316 | md_bitmap_endwrite(bitmap: conf->mddev->bitmap, offset: sh->sector, |
317 | RAID5_STRIPE_SECTORS(conf), |
318 | success: !test_bit(STRIPE_DEGRADED, &sh->state), |
319 | behind: 0); |
320 | } |
321 | } |
322 | } |
323 | |
324 | void r5l_wake_reclaim(struct r5l_log *log, sector_t space); |
325 | |
326 | /* Check whether we should flush some stripes to free up stripe cache */ |
327 | void r5c_check_stripe_cache_usage(struct r5conf *conf) |
328 | { |
329 | int total_cached; |
330 | struct r5l_log *log = READ_ONCE(conf->log); |
331 | |
332 | if (!r5c_is_writeback(log)) |
333 | return; |
334 | |
335 | total_cached = atomic_read(v: &conf->r5c_cached_partial_stripes) + |
336 | atomic_read(v: &conf->r5c_cached_full_stripes); |
337 | |
338 | /* |
339 | * The following condition is true for either of the following: |
340 | * - stripe cache pressure high: |
341 | * total_cached > 3/4 min_nr_stripes || |
342 | * empty_inactive_list_nr > 0 |
343 | * - stripe cache pressure moderate: |
344 | * total_cached > 1/2 min_nr_stripes |
345 | */ |
346 | if (total_cached > conf->min_nr_stripes * 1 / 2 || |
347 | atomic_read(v: &conf->empty_inactive_list_nr) > 0) |
348 | r5l_wake_reclaim(log, space: 0); |
349 | } |
350 | |
351 | /* |
352 | * flush cache when there are R5C_FULL_STRIPE_FLUSH_BATCH or more full |
353 | * stripes in the cache |
354 | */ |
355 | void r5c_check_cached_full_stripe(struct r5conf *conf) |
356 | { |
357 | struct r5l_log *log = READ_ONCE(conf->log); |
358 | |
359 | if (!r5c_is_writeback(log)) |
360 | return; |
361 | |
362 | /* |
363 | * wake up reclaim for R5C_FULL_STRIPE_FLUSH_BATCH cached stripes |
364 | * or a full stripe (chunk size / 4k stripes). |
365 | */ |
366 | if (atomic_read(v: &conf->r5c_cached_full_stripes) >= |
367 | min(R5C_FULL_STRIPE_FLUSH_BATCH(conf), |
368 | conf->chunk_sectors >> RAID5_STRIPE_SHIFT(conf))) |
369 | r5l_wake_reclaim(log, space: 0); |
370 | } |
371 | |
372 | /* |
373 | * Total log space (in sectors) needed to flush all data in cache |
374 | * |
375 | * To avoid deadlock due to log space, it is necessary to reserve log |
376 | * space to flush critical stripes (stripes that occupying log space near |
377 | * last_checkpoint). This function helps check how much log space is |
378 | * required to flush all cached stripes. |
379 | * |
380 | * To reduce log space requirements, two mechanisms are used to give cache |
381 | * flush higher priorities: |
382 | * 1. In handle_stripe_dirtying() and schedule_reconstruction(), |
383 | * stripes ALREADY in journal can be flushed w/o pending writes; |
384 | * 2. In r5l_write_stripe() and r5c_cache_data(), stripes NOT in journal |
385 | * can be delayed (r5l_add_no_space_stripe). |
386 | * |
387 | * In cache flush, the stripe goes through 1 and then 2. For a stripe that |
388 | * already passed 1, flushing it requires at most (conf->max_degraded + 1) |
389 | * pages of journal space. For stripes that has not passed 1, flushing it |
390 | * requires (conf->raid_disks + 1) pages of journal space. There are at |
391 | * most (conf->group_cnt + 1) stripe that passed 1. So total journal space |
392 | * required to flush all cached stripes (in pages) is: |
393 | * |
394 | * (stripe_in_journal_count - group_cnt - 1) * (max_degraded + 1) + |
395 | * (group_cnt + 1) * (raid_disks + 1) |
396 | * or |
397 | * (stripe_in_journal_count) * (max_degraded + 1) + |
398 | * (group_cnt + 1) * (raid_disks - max_degraded) |
399 | */ |
400 | static sector_t r5c_log_required_to_flush_cache(struct r5conf *conf) |
401 | { |
402 | struct r5l_log *log = READ_ONCE(conf->log); |
403 | |
404 | if (!r5c_is_writeback(log)) |
405 | return 0; |
406 | |
407 | return BLOCK_SECTORS * |
408 | ((conf->max_degraded + 1) * atomic_read(v: &log->stripe_in_journal_count) + |
409 | (conf->raid_disks - conf->max_degraded) * (conf->group_cnt + 1)); |
410 | } |
411 | |
412 | /* |
413 | * evaluate log space usage and update R5C_LOG_TIGHT and R5C_LOG_CRITICAL |
414 | * |
415 | * R5C_LOG_TIGHT is set when free space on the log device is less than 3x of |
416 | * reclaim_required_space. R5C_LOG_CRITICAL is set when free space on the log |
417 | * device is less than 2x of reclaim_required_space. |
418 | */ |
419 | static inline void r5c_update_log_state(struct r5l_log *log) |
420 | { |
421 | struct r5conf *conf = log->rdev->mddev->private; |
422 | sector_t free_space; |
423 | sector_t reclaim_space; |
424 | bool wake_reclaim = false; |
425 | |
426 | if (!r5c_is_writeback(log)) |
427 | return; |
428 | |
429 | free_space = r5l_ring_distance(log, start: log->log_start, |
430 | end: log->last_checkpoint); |
431 | reclaim_space = r5c_log_required_to_flush_cache(conf); |
432 | if (free_space < 2 * reclaim_space) |
433 | set_bit(nr: R5C_LOG_CRITICAL, addr: &conf->cache_state); |
434 | else { |
435 | if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state)) |
436 | wake_reclaim = true; |
437 | clear_bit(nr: R5C_LOG_CRITICAL, addr: &conf->cache_state); |
438 | } |
439 | if (free_space < 3 * reclaim_space) |
440 | set_bit(nr: R5C_LOG_TIGHT, addr: &conf->cache_state); |
441 | else |
442 | clear_bit(nr: R5C_LOG_TIGHT, addr: &conf->cache_state); |
443 | |
444 | if (wake_reclaim) |
445 | r5l_wake_reclaim(log, space: 0); |
446 | } |
447 | |
448 | /* |
449 | * Put the stripe into writing-out phase by clearing STRIPE_R5C_CACHING. |
450 | * This function should only be called in write-back mode. |
451 | */ |
452 | void r5c_make_stripe_write_out(struct stripe_head *sh) |
453 | { |
454 | struct r5conf *conf = sh->raid_conf; |
455 | struct r5l_log *log = READ_ONCE(conf->log); |
456 | |
457 | BUG_ON(!r5c_is_writeback(log)); |
458 | |
459 | WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state)); |
460 | clear_bit(nr: STRIPE_R5C_CACHING, addr: &sh->state); |
461 | |
462 | if (!test_and_set_bit(nr: STRIPE_PREREAD_ACTIVE, addr: &sh->state)) |
463 | atomic_inc(v: &conf->preread_active_stripes); |
464 | } |
465 | |
466 | static void r5c_handle_data_cached(struct stripe_head *sh) |
467 | { |
468 | int i; |
469 | |
470 | for (i = sh->disks; i--; ) |
471 | if (test_and_clear_bit(nr: R5_Wantwrite, addr: &sh->dev[i].flags)) { |
472 | set_bit(nr: R5_InJournal, addr: &sh->dev[i].flags); |
473 | clear_bit(nr: R5_LOCKED, addr: &sh->dev[i].flags); |
474 | } |
475 | clear_bit(nr: STRIPE_LOG_TRAPPED, addr: &sh->state); |
476 | } |
477 | |
478 | /* |
479 | * this journal write must contain full parity, |
480 | * it may also contain some data pages |
481 | */ |
482 | static void r5c_handle_parity_cached(struct stripe_head *sh) |
483 | { |
484 | int i; |
485 | |
486 | for (i = sh->disks; i--; ) |
487 | if (test_bit(R5_InJournal, &sh->dev[i].flags)) |
488 | set_bit(nr: R5_Wantwrite, addr: &sh->dev[i].flags); |
489 | } |
490 | |
491 | /* |
492 | * Setting proper flags after writing (or flushing) data and/or parity to the |
493 | * log device. This is called from r5l_log_endio() or r5l_log_flush_endio(). |
494 | */ |
495 | static void r5c_finish_cache_stripe(struct stripe_head *sh) |
496 | { |
497 | struct r5l_log *log = READ_ONCE(sh->raid_conf->log); |
498 | |
499 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) { |
500 | BUG_ON(test_bit(STRIPE_R5C_CACHING, &sh->state)); |
501 | /* |
502 | * Set R5_InJournal for parity dev[pd_idx]. This means |
503 | * all data AND parity in the journal. For RAID 6, it is |
504 | * NOT necessary to set the flag for dev[qd_idx], as the |
505 | * two parities are written out together. |
506 | */ |
507 | set_bit(nr: R5_InJournal, addr: &sh->dev[sh->pd_idx].flags); |
508 | } else if (test_bit(STRIPE_R5C_CACHING, &sh->state)) { |
509 | r5c_handle_data_cached(sh); |
510 | } else { |
511 | r5c_handle_parity_cached(sh); |
512 | set_bit(nr: R5_InJournal, addr: &sh->dev[sh->pd_idx].flags); |
513 | } |
514 | } |
515 | |
516 | static void r5l_io_run_stripes(struct r5l_io_unit *io) |
517 | { |
518 | struct stripe_head *sh, *next; |
519 | |
520 | list_for_each_entry_safe(sh, next, &io->stripe_list, log_list) { |
521 | list_del_init(entry: &sh->log_list); |
522 | |
523 | r5c_finish_cache_stripe(sh); |
524 | |
525 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
526 | raid5_release_stripe(sh); |
527 | } |
528 | } |
529 | |
530 | static void r5l_log_run_stripes(struct r5l_log *log) |
531 | { |
532 | struct r5l_io_unit *io, *next; |
533 | |
534 | lockdep_assert_held(&log->io_list_lock); |
535 | |
536 | list_for_each_entry_safe(io, next, &log->running_ios, log_sibling) { |
537 | /* don't change list order */ |
538 | if (io->state < IO_UNIT_IO_END) |
539 | break; |
540 | |
541 | list_move_tail(list: &io->log_sibling, head: &log->finished_ios); |
542 | r5l_io_run_stripes(io); |
543 | } |
544 | } |
545 | |
546 | static void r5l_move_to_end_ios(struct r5l_log *log) |
547 | { |
548 | struct r5l_io_unit *io, *next; |
549 | |
550 | lockdep_assert_held(&log->io_list_lock); |
551 | |
552 | list_for_each_entry_safe(io, next, &log->running_ios, log_sibling) { |
553 | /* don't change list order */ |
554 | if (io->state < IO_UNIT_IO_END) |
555 | break; |
556 | list_move_tail(list: &io->log_sibling, head: &log->io_end_ios); |
557 | } |
558 | } |
559 | |
560 | static void __r5l_stripe_write_finished(struct r5l_io_unit *io); |
561 | static void r5l_log_endio(struct bio *bio) |
562 | { |
563 | struct r5l_io_unit *io = bio->bi_private; |
564 | struct r5l_io_unit *io_deferred; |
565 | struct r5l_log *log = io->log; |
566 | unsigned long flags; |
567 | bool has_null_flush; |
568 | bool has_flush_payload; |
569 | |
570 | if (bio->bi_status) |
571 | md_error(mddev: log->rdev->mddev, rdev: log->rdev); |
572 | |
573 | bio_put(bio); |
574 | mempool_free(element: io->meta_page, pool: &log->meta_pool); |
575 | |
576 | spin_lock_irqsave(&log->io_list_lock, flags); |
577 | __r5l_set_io_unit_state(io, state: IO_UNIT_IO_END); |
578 | |
579 | /* |
580 | * if the io doesn't not have null_flush or flush payload, |
581 | * it is not safe to access it after releasing io_list_lock. |
582 | * Therefore, it is necessary to check the condition with |
583 | * the lock held. |
584 | */ |
585 | has_null_flush = io->has_null_flush; |
586 | has_flush_payload = io->has_flush_payload; |
587 | |
588 | if (log->need_cache_flush && !list_empty(head: &io->stripe_list)) |
589 | r5l_move_to_end_ios(log); |
590 | else |
591 | r5l_log_run_stripes(log); |
592 | if (!list_empty(head: &log->running_ios)) { |
593 | /* |
594 | * FLUSH/FUA io_unit is deferred because of ordering, now we |
595 | * can dispatch it |
596 | */ |
597 | io_deferred = list_first_entry(&log->running_ios, |
598 | struct r5l_io_unit, log_sibling); |
599 | if (io_deferred->io_deferred) |
600 | schedule_work(work: &log->deferred_io_work); |
601 | } |
602 | |
603 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
604 | |
605 | if (log->need_cache_flush) |
606 | md_wakeup_thread(thread: log->rdev->mddev->thread); |
607 | |
608 | /* finish flush only io_unit and PAYLOAD_FLUSH only io_unit */ |
609 | if (has_null_flush) { |
610 | struct bio *bi; |
611 | |
612 | WARN_ON(bio_list_empty(&io->flush_barriers)); |
613 | while ((bi = bio_list_pop(bl: &io->flush_barriers)) != NULL) { |
614 | bio_endio(bi); |
615 | if (atomic_dec_and_test(v: &io->pending_stripe)) { |
616 | __r5l_stripe_write_finished(io); |
617 | return; |
618 | } |
619 | } |
620 | } |
621 | /* decrease pending_stripe for flush payload */ |
622 | if (has_flush_payload) |
623 | if (atomic_dec_and_test(v: &io->pending_stripe)) |
624 | __r5l_stripe_write_finished(io); |
625 | } |
626 | |
627 | static void r5l_do_submit_io(struct r5l_log *log, struct r5l_io_unit *io) |
628 | { |
629 | unsigned long flags; |
630 | |
631 | spin_lock_irqsave(&log->io_list_lock, flags); |
632 | __r5l_set_io_unit_state(io, state: IO_UNIT_IO_START); |
633 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
634 | |
635 | /* |
636 | * In case of journal device failures, submit_bio will get error |
637 | * and calls endio, then active stripes will continue write |
638 | * process. Therefore, it is not necessary to check Faulty bit |
639 | * of journal device here. |
640 | * |
641 | * We can't check split_bio after current_bio is submitted. If |
642 | * io->split_bio is null, after current_bio is submitted, current_bio |
643 | * might already be completed and the io_unit is freed. We submit |
644 | * split_bio first to avoid the issue. |
645 | */ |
646 | if (io->split_bio) { |
647 | if (io->has_flush) |
648 | io->split_bio->bi_opf |= REQ_PREFLUSH; |
649 | if (io->has_fua) |
650 | io->split_bio->bi_opf |= REQ_FUA; |
651 | submit_bio(bio: io->split_bio); |
652 | } |
653 | |
654 | if (io->has_flush) |
655 | io->current_bio->bi_opf |= REQ_PREFLUSH; |
656 | if (io->has_fua) |
657 | io->current_bio->bi_opf |= REQ_FUA; |
658 | submit_bio(bio: io->current_bio); |
659 | } |
660 | |
661 | /* deferred io_unit will be dispatched here */ |
662 | static void r5l_submit_io_async(struct work_struct *work) |
663 | { |
664 | struct r5l_log *log = container_of(work, struct r5l_log, |
665 | deferred_io_work); |
666 | struct r5l_io_unit *io = NULL; |
667 | unsigned long flags; |
668 | |
669 | spin_lock_irqsave(&log->io_list_lock, flags); |
670 | if (!list_empty(head: &log->running_ios)) { |
671 | io = list_first_entry(&log->running_ios, struct r5l_io_unit, |
672 | log_sibling); |
673 | if (!io->io_deferred) |
674 | io = NULL; |
675 | else |
676 | io->io_deferred = 0; |
677 | } |
678 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
679 | if (io) |
680 | r5l_do_submit_io(log, io); |
681 | } |
682 | |
683 | static void r5c_disable_writeback_async(struct work_struct *work) |
684 | { |
685 | struct r5l_log *log = container_of(work, struct r5l_log, |
686 | disable_writeback_work); |
687 | struct mddev *mddev = log->rdev->mddev; |
688 | struct r5conf *conf = mddev->private; |
689 | |
690 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) |
691 | return; |
692 | pr_info("md/raid:%s: Disabling writeback cache for degraded array.\n" , |
693 | mdname(mddev)); |
694 | |
695 | /* wait superblock change before suspend */ |
696 | wait_event(mddev->sb_wait, |
697 | !READ_ONCE(conf->log) || |
698 | !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)); |
699 | |
700 | log = READ_ONCE(conf->log); |
701 | if (log) { |
702 | mddev_suspend(mddev, interruptible: false); |
703 | log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH; |
704 | mddev_resume(mddev); |
705 | } |
706 | } |
707 | |
708 | static void r5l_submit_current_io(struct r5l_log *log) |
709 | { |
710 | struct r5l_io_unit *io = log->current_io; |
711 | struct r5l_meta_block *block; |
712 | unsigned long flags; |
713 | u32 crc; |
714 | bool do_submit = true; |
715 | |
716 | if (!io) |
717 | return; |
718 | |
719 | block = page_address(io->meta_page); |
720 | block->meta_size = cpu_to_le32(io->meta_offset); |
721 | crc = crc32c_le(crc: log->uuid_checksum, address: block, PAGE_SIZE); |
722 | block->checksum = cpu_to_le32(crc); |
723 | |
724 | log->current_io = NULL; |
725 | spin_lock_irqsave(&log->io_list_lock, flags); |
726 | if (io->has_flush || io->has_fua) { |
727 | if (io != list_first_entry(&log->running_ios, |
728 | struct r5l_io_unit, log_sibling)) { |
729 | io->io_deferred = 1; |
730 | do_submit = false; |
731 | } |
732 | } |
733 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
734 | if (do_submit) |
735 | r5l_do_submit_io(log, io); |
736 | } |
737 | |
738 | static struct bio *r5l_bio_alloc(struct r5l_log *log) |
739 | { |
740 | struct bio *bio = bio_alloc_bioset(bdev: log->rdev->bdev, BIO_MAX_VECS, |
741 | opf: REQ_OP_WRITE, GFP_NOIO, bs: &log->bs); |
742 | |
743 | bio->bi_iter.bi_sector = log->rdev->data_offset + log->log_start; |
744 | |
745 | return bio; |
746 | } |
747 | |
748 | static void r5_reserve_log_entry(struct r5l_log *log, struct r5l_io_unit *io) |
749 | { |
750 | log->log_start = r5l_ring_add(log, start: log->log_start, BLOCK_SECTORS); |
751 | |
752 | r5c_update_log_state(log); |
753 | /* |
754 | * If we filled up the log device start from the beginning again, |
755 | * which will require a new bio. |
756 | * |
757 | * Note: for this to work properly the log size needs to me a multiple |
758 | * of BLOCK_SECTORS. |
759 | */ |
760 | if (log->log_start == 0) |
761 | io->need_split_bio = true; |
762 | |
763 | io->log_end = log->log_start; |
764 | } |
765 | |
766 | static struct r5l_io_unit *r5l_new_meta(struct r5l_log *log) |
767 | { |
768 | struct r5l_io_unit *io; |
769 | struct r5l_meta_block *block; |
770 | |
771 | io = mempool_alloc(pool: &log->io_pool, GFP_ATOMIC); |
772 | if (!io) |
773 | return NULL; |
774 | memset(io, 0, sizeof(*io)); |
775 | |
776 | io->log = log; |
777 | INIT_LIST_HEAD(list: &io->log_sibling); |
778 | INIT_LIST_HEAD(list: &io->stripe_list); |
779 | bio_list_init(bl: &io->flush_barriers); |
780 | io->state = IO_UNIT_RUNNING; |
781 | |
782 | io->meta_page = mempool_alloc(pool: &log->meta_pool, GFP_NOIO); |
783 | block = page_address(io->meta_page); |
784 | clear_page(page: block); |
785 | block->magic = cpu_to_le32(R5LOG_MAGIC); |
786 | block->version = R5LOG_VERSION; |
787 | block->seq = cpu_to_le64(log->seq); |
788 | block->position = cpu_to_le64(log->log_start); |
789 | |
790 | io->log_start = log->log_start; |
791 | io->meta_offset = sizeof(struct r5l_meta_block); |
792 | io->seq = log->seq++; |
793 | |
794 | io->current_bio = r5l_bio_alloc(log); |
795 | io->current_bio->bi_end_io = r5l_log_endio; |
796 | io->current_bio->bi_private = io; |
797 | __bio_add_page(bio: io->current_bio, page: io->meta_page, PAGE_SIZE, off: 0); |
798 | |
799 | r5_reserve_log_entry(log, io); |
800 | |
801 | spin_lock_irq(lock: &log->io_list_lock); |
802 | list_add_tail(new: &io->log_sibling, head: &log->running_ios); |
803 | spin_unlock_irq(lock: &log->io_list_lock); |
804 | |
805 | return io; |
806 | } |
807 | |
808 | static int r5l_get_meta(struct r5l_log *log, unsigned int payload_size) |
809 | { |
810 | if (log->current_io && |
811 | log->current_io->meta_offset + payload_size > PAGE_SIZE) |
812 | r5l_submit_current_io(log); |
813 | |
814 | if (!log->current_io) { |
815 | log->current_io = r5l_new_meta(log); |
816 | if (!log->current_io) |
817 | return -ENOMEM; |
818 | } |
819 | |
820 | return 0; |
821 | } |
822 | |
823 | static void r5l_append_payload_meta(struct r5l_log *log, u16 type, |
824 | sector_t location, |
825 | u32 checksum1, u32 checksum2, |
826 | bool checksum2_valid) |
827 | { |
828 | struct r5l_io_unit *io = log->current_io; |
829 | struct r5l_payload_data_parity *payload; |
830 | |
831 | payload = page_address(io->meta_page) + io->meta_offset; |
832 | payload->header.type = cpu_to_le16(type); |
833 | payload->header.flags = cpu_to_le16(0); |
834 | payload->size = cpu_to_le32((1 + !!checksum2_valid) << |
835 | (PAGE_SHIFT - 9)); |
836 | payload->location = cpu_to_le64(location); |
837 | payload->checksum[0] = cpu_to_le32(checksum1); |
838 | if (checksum2_valid) |
839 | payload->checksum[1] = cpu_to_le32(checksum2); |
840 | |
841 | io->meta_offset += sizeof(struct r5l_payload_data_parity) + |
842 | sizeof(__le32) * (1 + !!checksum2_valid); |
843 | } |
844 | |
845 | static void r5l_append_payload_page(struct r5l_log *log, struct page *page) |
846 | { |
847 | struct r5l_io_unit *io = log->current_io; |
848 | |
849 | if (io->need_split_bio) { |
850 | BUG_ON(io->split_bio); |
851 | io->split_bio = io->current_bio; |
852 | io->current_bio = r5l_bio_alloc(log); |
853 | bio_chain(io->current_bio, io->split_bio); |
854 | io->need_split_bio = false; |
855 | } |
856 | |
857 | if (!bio_add_page(bio: io->current_bio, page, PAGE_SIZE, off: 0)) |
858 | BUG(); |
859 | |
860 | r5_reserve_log_entry(log, io); |
861 | } |
862 | |
863 | static void r5l_append_flush_payload(struct r5l_log *log, sector_t sect) |
864 | { |
865 | struct mddev *mddev = log->rdev->mddev; |
866 | struct r5conf *conf = mddev->private; |
867 | struct r5l_io_unit *io; |
868 | struct r5l_payload_flush *payload; |
869 | int meta_size; |
870 | |
871 | /* |
872 | * payload_flush requires extra writes to the journal. |
873 | * To avoid handling the extra IO in quiesce, just skip |
874 | * flush_payload |
875 | */ |
876 | if (conf->quiesce) |
877 | return; |
878 | |
879 | mutex_lock(&log->io_mutex); |
880 | meta_size = sizeof(struct r5l_payload_flush) + sizeof(__le64); |
881 | |
882 | if (r5l_get_meta(log, payload_size: meta_size)) { |
883 | mutex_unlock(lock: &log->io_mutex); |
884 | return; |
885 | } |
886 | |
887 | /* current implementation is one stripe per flush payload */ |
888 | io = log->current_io; |
889 | payload = page_address(io->meta_page) + io->meta_offset; |
890 | payload->header.type = cpu_to_le16(R5LOG_PAYLOAD_FLUSH); |
891 | payload->header.flags = cpu_to_le16(0); |
892 | payload->size = cpu_to_le32(sizeof(__le64)); |
893 | payload->flush_stripes[0] = cpu_to_le64(sect); |
894 | io->meta_offset += meta_size; |
895 | /* multiple flush payloads count as one pending_stripe */ |
896 | if (!io->has_flush_payload) { |
897 | io->has_flush_payload = 1; |
898 | atomic_inc(v: &io->pending_stripe); |
899 | } |
900 | mutex_unlock(lock: &log->io_mutex); |
901 | } |
902 | |
903 | static int r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh, |
904 | int data_pages, int parity_pages) |
905 | { |
906 | int i; |
907 | int meta_size; |
908 | int ret; |
909 | struct r5l_io_unit *io; |
910 | |
911 | meta_size = |
912 | ((sizeof(struct r5l_payload_data_parity) + sizeof(__le32)) |
913 | * data_pages) + |
914 | sizeof(struct r5l_payload_data_parity) + |
915 | sizeof(__le32) * parity_pages; |
916 | |
917 | ret = r5l_get_meta(log, payload_size: meta_size); |
918 | if (ret) |
919 | return ret; |
920 | |
921 | io = log->current_io; |
922 | |
923 | if (test_and_clear_bit(nr: STRIPE_R5C_PREFLUSH, addr: &sh->state)) |
924 | io->has_flush = 1; |
925 | |
926 | for (i = 0; i < sh->disks; i++) { |
927 | if (!test_bit(R5_Wantwrite, &sh->dev[i].flags) || |
928 | test_bit(R5_InJournal, &sh->dev[i].flags)) |
929 | continue; |
930 | if (i == sh->pd_idx || i == sh->qd_idx) |
931 | continue; |
932 | if (test_bit(R5_WantFUA, &sh->dev[i].flags) && |
933 | log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK) { |
934 | io->has_fua = 1; |
935 | /* |
936 | * we need to flush journal to make sure recovery can |
937 | * reach the data with fua flag |
938 | */ |
939 | io->has_flush = 1; |
940 | } |
941 | r5l_append_payload_meta(log, type: R5LOG_PAYLOAD_DATA, |
942 | location: raid5_compute_blocknr(sh, i, previous: 0), |
943 | checksum1: sh->dev[i].log_checksum, checksum2: 0, checksum2_valid: false); |
944 | r5l_append_payload_page(log, page: sh->dev[i].page); |
945 | } |
946 | |
947 | if (parity_pages == 2) { |
948 | r5l_append_payload_meta(log, type: R5LOG_PAYLOAD_PARITY, |
949 | location: sh->sector, checksum1: sh->dev[sh->pd_idx].log_checksum, |
950 | checksum2: sh->dev[sh->qd_idx].log_checksum, checksum2_valid: true); |
951 | r5l_append_payload_page(log, page: sh->dev[sh->pd_idx].page); |
952 | r5l_append_payload_page(log, page: sh->dev[sh->qd_idx].page); |
953 | } else if (parity_pages == 1) { |
954 | r5l_append_payload_meta(log, type: R5LOG_PAYLOAD_PARITY, |
955 | location: sh->sector, checksum1: sh->dev[sh->pd_idx].log_checksum, |
956 | checksum2: 0, checksum2_valid: false); |
957 | r5l_append_payload_page(log, page: sh->dev[sh->pd_idx].page); |
958 | } else /* Just writing data, not parity, in caching phase */ |
959 | BUG_ON(parity_pages != 0); |
960 | |
961 | list_add_tail(new: &sh->log_list, head: &io->stripe_list); |
962 | atomic_inc(v: &io->pending_stripe); |
963 | sh->log_io = io; |
964 | |
965 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) |
966 | return 0; |
967 | |
968 | if (sh->log_start == MaxSector) { |
969 | BUG_ON(!list_empty(&sh->r5c)); |
970 | sh->log_start = io->log_start; |
971 | spin_lock_irq(lock: &log->stripe_in_journal_lock); |
972 | list_add_tail(new: &sh->r5c, |
973 | head: &log->stripe_in_journal_list); |
974 | spin_unlock_irq(lock: &log->stripe_in_journal_lock); |
975 | atomic_inc(v: &log->stripe_in_journal_count); |
976 | } |
977 | return 0; |
978 | } |
979 | |
980 | /* add stripe to no_space_stripes, and then wake up reclaim */ |
981 | static inline void r5l_add_no_space_stripe(struct r5l_log *log, |
982 | struct stripe_head *sh) |
983 | { |
984 | spin_lock(lock: &log->no_space_stripes_lock); |
985 | list_add_tail(new: &sh->log_list, head: &log->no_space_stripes); |
986 | spin_unlock(lock: &log->no_space_stripes_lock); |
987 | } |
988 | |
989 | /* |
990 | * running in raid5d, where reclaim could wait for raid5d too (when it flushes |
991 | * data from log to raid disks), so we shouldn't wait for reclaim here |
992 | */ |
993 | int r5l_write_stripe(struct r5l_log *log, struct stripe_head *sh) |
994 | { |
995 | struct r5conf *conf = sh->raid_conf; |
996 | int write_disks = 0; |
997 | int data_pages, parity_pages; |
998 | int reserve; |
999 | int i; |
1000 | int ret = 0; |
1001 | bool wake_reclaim = false; |
1002 | |
1003 | if (!log) |
1004 | return -EAGAIN; |
1005 | /* Don't support stripe batch */ |
1006 | if (sh->log_io || !test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags) || |
1007 | test_bit(STRIPE_SYNCING, &sh->state)) { |
1008 | /* the stripe is written to log, we start writing it to raid */ |
1009 | clear_bit(nr: STRIPE_LOG_TRAPPED, addr: &sh->state); |
1010 | return -EAGAIN; |
1011 | } |
1012 | |
1013 | WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state)); |
1014 | |
1015 | for (i = 0; i < sh->disks; i++) { |
1016 | void *addr; |
1017 | |
1018 | if (!test_bit(R5_Wantwrite, &sh->dev[i].flags) || |
1019 | test_bit(R5_InJournal, &sh->dev[i].flags)) |
1020 | continue; |
1021 | |
1022 | write_disks++; |
1023 | /* checksum is already calculated in last run */ |
1024 | if (test_bit(STRIPE_LOG_TRAPPED, &sh->state)) |
1025 | continue; |
1026 | addr = kmap_atomic(page: sh->dev[i].page); |
1027 | sh->dev[i].log_checksum = crc32c_le(crc: log->uuid_checksum, |
1028 | address: addr, PAGE_SIZE); |
1029 | kunmap_atomic(addr); |
1030 | } |
1031 | parity_pages = 1 + !!(sh->qd_idx >= 0); |
1032 | data_pages = write_disks - parity_pages; |
1033 | |
1034 | set_bit(nr: STRIPE_LOG_TRAPPED, addr: &sh->state); |
1035 | /* |
1036 | * The stripe must enter state machine again to finish the write, so |
1037 | * don't delay. |
1038 | */ |
1039 | clear_bit(nr: STRIPE_DELAYED, addr: &sh->state); |
1040 | atomic_inc(v: &sh->count); |
1041 | |
1042 | mutex_lock(&log->io_mutex); |
1043 | /* meta + data */ |
1044 | reserve = (1 + write_disks) << (PAGE_SHIFT - 9); |
1045 | |
1046 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) { |
1047 | if (!r5l_has_free_space(log, size: reserve)) { |
1048 | r5l_add_no_space_stripe(log, sh); |
1049 | wake_reclaim = true; |
1050 | } else { |
1051 | ret = r5l_log_stripe(log, sh, data_pages, parity_pages); |
1052 | if (ret) { |
1053 | spin_lock_irq(lock: &log->io_list_lock); |
1054 | list_add_tail(new: &sh->log_list, |
1055 | head: &log->no_mem_stripes); |
1056 | spin_unlock_irq(lock: &log->io_list_lock); |
1057 | } |
1058 | } |
1059 | } else { /* R5C_JOURNAL_MODE_WRITE_BACK */ |
1060 | /* |
1061 | * log space critical, do not process stripes that are |
1062 | * not in cache yet (sh->log_start == MaxSector). |
1063 | */ |
1064 | if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) && |
1065 | sh->log_start == MaxSector) { |
1066 | r5l_add_no_space_stripe(log, sh); |
1067 | wake_reclaim = true; |
1068 | reserve = 0; |
1069 | } else if (!r5l_has_free_space(log, size: reserve)) { |
1070 | if (sh->log_start == log->last_checkpoint) |
1071 | BUG(); |
1072 | else |
1073 | r5l_add_no_space_stripe(log, sh); |
1074 | } else { |
1075 | ret = r5l_log_stripe(log, sh, data_pages, parity_pages); |
1076 | if (ret) { |
1077 | spin_lock_irq(lock: &log->io_list_lock); |
1078 | list_add_tail(new: &sh->log_list, |
1079 | head: &log->no_mem_stripes); |
1080 | spin_unlock_irq(lock: &log->io_list_lock); |
1081 | } |
1082 | } |
1083 | } |
1084 | |
1085 | mutex_unlock(lock: &log->io_mutex); |
1086 | if (wake_reclaim) |
1087 | r5l_wake_reclaim(log, space: reserve); |
1088 | return 0; |
1089 | } |
1090 | |
1091 | void r5l_write_stripe_run(struct r5l_log *log) |
1092 | { |
1093 | if (!log) |
1094 | return; |
1095 | mutex_lock(&log->io_mutex); |
1096 | r5l_submit_current_io(log); |
1097 | mutex_unlock(lock: &log->io_mutex); |
1098 | } |
1099 | |
1100 | int r5l_handle_flush_request(struct r5l_log *log, struct bio *bio) |
1101 | { |
1102 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) { |
1103 | /* |
1104 | * in write through (journal only) |
1105 | * we flush log disk cache first, then write stripe data to |
1106 | * raid disks. So if bio is finished, the log disk cache is |
1107 | * flushed already. The recovery guarantees we can recovery |
1108 | * the bio from log disk, so we don't need to flush again |
1109 | */ |
1110 | if (bio->bi_iter.bi_size == 0) { |
1111 | bio_endio(bio); |
1112 | return 0; |
1113 | } |
1114 | bio->bi_opf &= ~REQ_PREFLUSH; |
1115 | } else { |
1116 | /* write back (with cache) */ |
1117 | if (bio->bi_iter.bi_size == 0) { |
1118 | mutex_lock(&log->io_mutex); |
1119 | r5l_get_meta(log, payload_size: 0); |
1120 | bio_list_add(bl: &log->current_io->flush_barriers, bio); |
1121 | log->current_io->has_flush = 1; |
1122 | log->current_io->has_null_flush = 1; |
1123 | atomic_inc(v: &log->current_io->pending_stripe); |
1124 | r5l_submit_current_io(log); |
1125 | mutex_unlock(lock: &log->io_mutex); |
1126 | return 0; |
1127 | } |
1128 | } |
1129 | return -EAGAIN; |
1130 | } |
1131 | |
1132 | /* This will run after log space is reclaimed */ |
1133 | static void r5l_run_no_space_stripes(struct r5l_log *log) |
1134 | { |
1135 | struct stripe_head *sh; |
1136 | |
1137 | spin_lock(lock: &log->no_space_stripes_lock); |
1138 | while (!list_empty(head: &log->no_space_stripes)) { |
1139 | sh = list_first_entry(&log->no_space_stripes, |
1140 | struct stripe_head, log_list); |
1141 | list_del_init(entry: &sh->log_list); |
1142 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
1143 | raid5_release_stripe(sh); |
1144 | } |
1145 | spin_unlock(lock: &log->no_space_stripes_lock); |
1146 | } |
1147 | |
1148 | /* |
1149 | * calculate new last_checkpoint |
1150 | * for write through mode, returns log->next_checkpoint |
1151 | * for write back, returns log_start of first sh in stripe_in_journal_list |
1152 | */ |
1153 | static sector_t r5c_calculate_new_cp(struct r5conf *conf) |
1154 | { |
1155 | struct stripe_head *sh; |
1156 | struct r5l_log *log = READ_ONCE(conf->log); |
1157 | sector_t new_cp; |
1158 | unsigned long flags; |
1159 | |
1160 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) |
1161 | return log->next_checkpoint; |
1162 | |
1163 | spin_lock_irqsave(&log->stripe_in_journal_lock, flags); |
1164 | if (list_empty(head: &log->stripe_in_journal_list)) { |
1165 | /* all stripes flushed */ |
1166 | spin_unlock_irqrestore(lock: &log->stripe_in_journal_lock, flags); |
1167 | return log->next_checkpoint; |
1168 | } |
1169 | sh = list_first_entry(&log->stripe_in_journal_list, |
1170 | struct stripe_head, r5c); |
1171 | new_cp = sh->log_start; |
1172 | spin_unlock_irqrestore(lock: &log->stripe_in_journal_lock, flags); |
1173 | return new_cp; |
1174 | } |
1175 | |
1176 | static sector_t r5l_reclaimable_space(struct r5l_log *log) |
1177 | { |
1178 | struct r5conf *conf = log->rdev->mddev->private; |
1179 | |
1180 | return r5l_ring_distance(log, start: log->last_checkpoint, |
1181 | end: r5c_calculate_new_cp(conf)); |
1182 | } |
1183 | |
1184 | static void r5l_run_no_mem_stripe(struct r5l_log *log) |
1185 | { |
1186 | struct stripe_head *sh; |
1187 | |
1188 | lockdep_assert_held(&log->io_list_lock); |
1189 | |
1190 | if (!list_empty(head: &log->no_mem_stripes)) { |
1191 | sh = list_first_entry(&log->no_mem_stripes, |
1192 | struct stripe_head, log_list); |
1193 | list_del_init(entry: &sh->log_list); |
1194 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
1195 | raid5_release_stripe(sh); |
1196 | } |
1197 | } |
1198 | |
1199 | static bool r5l_complete_finished_ios(struct r5l_log *log) |
1200 | { |
1201 | struct r5l_io_unit *io, *next; |
1202 | bool found = false; |
1203 | |
1204 | lockdep_assert_held(&log->io_list_lock); |
1205 | |
1206 | list_for_each_entry_safe(io, next, &log->finished_ios, log_sibling) { |
1207 | /* don't change list order */ |
1208 | if (io->state < IO_UNIT_STRIPE_END) |
1209 | break; |
1210 | |
1211 | log->next_checkpoint = io->log_start; |
1212 | |
1213 | list_del(entry: &io->log_sibling); |
1214 | mempool_free(element: io, pool: &log->io_pool); |
1215 | r5l_run_no_mem_stripe(log); |
1216 | |
1217 | found = true; |
1218 | } |
1219 | |
1220 | return found; |
1221 | } |
1222 | |
1223 | static void __r5l_stripe_write_finished(struct r5l_io_unit *io) |
1224 | { |
1225 | struct r5l_log *log = io->log; |
1226 | struct r5conf *conf = log->rdev->mddev->private; |
1227 | unsigned long flags; |
1228 | |
1229 | spin_lock_irqsave(&log->io_list_lock, flags); |
1230 | __r5l_set_io_unit_state(io, state: IO_UNIT_STRIPE_END); |
1231 | |
1232 | if (!r5l_complete_finished_ios(log)) { |
1233 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
1234 | return; |
1235 | } |
1236 | |
1237 | if (r5l_reclaimable_space(log) > log->max_free_space || |
1238 | test_bit(R5C_LOG_TIGHT, &conf->cache_state)) |
1239 | r5l_wake_reclaim(log, space: 0); |
1240 | |
1241 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
1242 | wake_up(&log->iounit_wait); |
1243 | } |
1244 | |
1245 | void r5l_stripe_write_finished(struct stripe_head *sh) |
1246 | { |
1247 | struct r5l_io_unit *io; |
1248 | |
1249 | io = sh->log_io; |
1250 | sh->log_io = NULL; |
1251 | |
1252 | if (io && atomic_dec_and_test(v: &io->pending_stripe)) |
1253 | __r5l_stripe_write_finished(io); |
1254 | } |
1255 | |
1256 | static void r5l_log_flush_endio(struct bio *bio) |
1257 | { |
1258 | struct r5l_log *log = container_of(bio, struct r5l_log, |
1259 | flush_bio); |
1260 | unsigned long flags; |
1261 | struct r5l_io_unit *io; |
1262 | |
1263 | if (bio->bi_status) |
1264 | md_error(mddev: log->rdev->mddev, rdev: log->rdev); |
1265 | bio_uninit(bio); |
1266 | |
1267 | spin_lock_irqsave(&log->io_list_lock, flags); |
1268 | list_for_each_entry(io, &log->flushing_ios, log_sibling) |
1269 | r5l_io_run_stripes(io); |
1270 | list_splice_tail_init(list: &log->flushing_ios, head: &log->finished_ios); |
1271 | spin_unlock_irqrestore(lock: &log->io_list_lock, flags); |
1272 | } |
1273 | |
1274 | /* |
1275 | * Starting dispatch IO to raid. |
1276 | * io_unit(meta) consists of a log. There is one situation we want to avoid. A |
1277 | * broken meta in the middle of a log causes recovery can't find meta at the |
1278 | * head of log. If operations require meta at the head persistent in log, we |
1279 | * must make sure meta before it persistent in log too. A case is: |
1280 | * |
1281 | * stripe data/parity is in log, we start write stripe to raid disks. stripe |
1282 | * data/parity must be persistent in log before we do the write to raid disks. |
1283 | * |
1284 | * The solution is we restrictly maintain io_unit list order. In this case, we |
1285 | * only write stripes of an io_unit to raid disks till the io_unit is the first |
1286 | * one whose data/parity is in log. |
1287 | */ |
1288 | void r5l_flush_stripe_to_raid(struct r5l_log *log) |
1289 | { |
1290 | bool do_flush; |
1291 | |
1292 | if (!log || !log->need_cache_flush) |
1293 | return; |
1294 | |
1295 | spin_lock_irq(lock: &log->io_list_lock); |
1296 | /* flush bio is running */ |
1297 | if (!list_empty(head: &log->flushing_ios)) { |
1298 | spin_unlock_irq(lock: &log->io_list_lock); |
1299 | return; |
1300 | } |
1301 | list_splice_tail_init(list: &log->io_end_ios, head: &log->flushing_ios); |
1302 | do_flush = !list_empty(head: &log->flushing_ios); |
1303 | spin_unlock_irq(lock: &log->io_list_lock); |
1304 | |
1305 | if (!do_flush) |
1306 | return; |
1307 | bio_init(bio: &log->flush_bio, bdev: log->rdev->bdev, NULL, max_vecs: 0, |
1308 | opf: REQ_OP_WRITE | REQ_PREFLUSH); |
1309 | log->flush_bio.bi_end_io = r5l_log_flush_endio; |
1310 | submit_bio(bio: &log->flush_bio); |
1311 | } |
1312 | |
1313 | static void r5l_write_super(struct r5l_log *log, sector_t cp); |
1314 | static void r5l_write_super_and_discard_space(struct r5l_log *log, |
1315 | sector_t end) |
1316 | { |
1317 | struct block_device *bdev = log->rdev->bdev; |
1318 | struct mddev *mddev; |
1319 | |
1320 | r5l_write_super(log, cp: end); |
1321 | |
1322 | if (!bdev_max_discard_sectors(bdev)) |
1323 | return; |
1324 | |
1325 | mddev = log->rdev->mddev; |
1326 | /* |
1327 | * Discard could zero data, so before discard we must make sure |
1328 | * superblock is updated to new log tail. Updating superblock (either |
1329 | * directly call md_update_sb() or depend on md thread) must hold |
1330 | * reconfig mutex. On the other hand, raid5_quiesce is called with |
1331 | * reconfig_mutex hold. The first step of raid5_quiesce() is waiting |
1332 | * for all IO finish, hence waiting for reclaim thread, while reclaim |
1333 | * thread is calling this function and waiting for reconfig mutex. So |
1334 | * there is a deadlock. We workaround this issue with a trylock. |
1335 | * FIXME: we could miss discard if we can't take reconfig mutex |
1336 | */ |
1337 | set_mask_bits(&mddev->sb_flags, 0, |
1338 | BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING)); |
1339 | if (!mddev_trylock(mddev)) |
1340 | return; |
1341 | md_update_sb(mddev, force: 1); |
1342 | mddev_unlock(mddev); |
1343 | |
1344 | /* discard IO error really doesn't matter, ignore it */ |
1345 | if (log->last_checkpoint < end) { |
1346 | blkdev_issue_discard(bdev, |
1347 | sector: log->last_checkpoint + log->rdev->data_offset, |
1348 | nr_sects: end - log->last_checkpoint, GFP_NOIO); |
1349 | } else { |
1350 | blkdev_issue_discard(bdev, |
1351 | sector: log->last_checkpoint + log->rdev->data_offset, |
1352 | nr_sects: log->device_size - log->last_checkpoint, |
1353 | GFP_NOIO); |
1354 | blkdev_issue_discard(bdev, sector: log->rdev->data_offset, nr_sects: end, |
1355 | GFP_NOIO); |
1356 | } |
1357 | } |
1358 | |
1359 | /* |
1360 | * r5c_flush_stripe moves stripe from cached list to handle_list. When called, |
1361 | * the stripe must be on r5c_cached_full_stripes or r5c_cached_partial_stripes. |
1362 | * |
1363 | * must hold conf->device_lock |
1364 | */ |
1365 | static void r5c_flush_stripe(struct r5conf *conf, struct stripe_head *sh) |
1366 | { |
1367 | BUG_ON(list_empty(&sh->lru)); |
1368 | BUG_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state)); |
1369 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); |
1370 | |
1371 | /* |
1372 | * The stripe is not ON_RELEASE_LIST, so it is safe to call |
1373 | * raid5_release_stripe() while holding conf->device_lock |
1374 | */ |
1375 | BUG_ON(test_bit(STRIPE_ON_RELEASE_LIST, &sh->state)); |
1376 | lockdep_assert_held(&conf->device_lock); |
1377 | |
1378 | list_del_init(entry: &sh->lru); |
1379 | atomic_inc(v: &sh->count); |
1380 | |
1381 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
1382 | atomic_inc(v: &conf->active_stripes); |
1383 | r5c_make_stripe_write_out(sh); |
1384 | |
1385 | if (test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) |
1386 | atomic_inc(v: &conf->r5c_flushing_partial_stripes); |
1387 | else |
1388 | atomic_inc(v: &conf->r5c_flushing_full_stripes); |
1389 | raid5_release_stripe(sh); |
1390 | } |
1391 | |
1392 | /* |
1393 | * if num == 0, flush all full stripes |
1394 | * if num > 0, flush all full stripes. If less than num full stripes are |
1395 | * flushed, flush some partial stripes until totally num stripes are |
1396 | * flushed or there is no more cached stripes. |
1397 | */ |
1398 | void r5c_flush_cache(struct r5conf *conf, int num) |
1399 | { |
1400 | int count; |
1401 | struct stripe_head *sh, *next; |
1402 | |
1403 | lockdep_assert_held(&conf->device_lock); |
1404 | if (!READ_ONCE(conf->log)) |
1405 | return; |
1406 | |
1407 | count = 0; |
1408 | list_for_each_entry_safe(sh, next, &conf->r5c_full_stripe_list, lru) { |
1409 | r5c_flush_stripe(conf, sh); |
1410 | count++; |
1411 | } |
1412 | |
1413 | if (count >= num) |
1414 | return; |
1415 | list_for_each_entry_safe(sh, next, |
1416 | &conf->r5c_partial_stripe_list, lru) { |
1417 | r5c_flush_stripe(conf, sh); |
1418 | if (++count >= num) |
1419 | break; |
1420 | } |
1421 | } |
1422 | |
1423 | static void r5c_do_reclaim(struct r5conf *conf) |
1424 | { |
1425 | struct r5l_log *log = READ_ONCE(conf->log); |
1426 | struct stripe_head *sh; |
1427 | int count = 0; |
1428 | unsigned long flags; |
1429 | int total_cached; |
1430 | int stripes_to_flush; |
1431 | int flushing_partial, flushing_full; |
1432 | |
1433 | if (!r5c_is_writeback(log)) |
1434 | return; |
1435 | |
1436 | flushing_partial = atomic_read(v: &conf->r5c_flushing_partial_stripes); |
1437 | flushing_full = atomic_read(v: &conf->r5c_flushing_full_stripes); |
1438 | total_cached = atomic_read(v: &conf->r5c_cached_partial_stripes) + |
1439 | atomic_read(v: &conf->r5c_cached_full_stripes) - |
1440 | flushing_full - flushing_partial; |
1441 | |
1442 | if (total_cached > conf->min_nr_stripes * 3 / 4 || |
1443 | atomic_read(v: &conf->empty_inactive_list_nr) > 0) |
1444 | /* |
1445 | * if stripe cache pressure high, flush all full stripes and |
1446 | * some partial stripes |
1447 | */ |
1448 | stripes_to_flush = R5C_RECLAIM_STRIPE_GROUP; |
1449 | else if (total_cached > conf->min_nr_stripes * 1 / 2 || |
1450 | atomic_read(v: &conf->r5c_cached_full_stripes) - flushing_full > |
1451 | R5C_FULL_STRIPE_FLUSH_BATCH(conf)) |
1452 | /* |
1453 | * if stripe cache pressure moderate, or if there is many full |
1454 | * stripes,flush all full stripes |
1455 | */ |
1456 | stripes_to_flush = 0; |
1457 | else |
1458 | /* no need to flush */ |
1459 | stripes_to_flush = -1; |
1460 | |
1461 | if (stripes_to_flush >= 0) { |
1462 | spin_lock_irqsave(&conf->device_lock, flags); |
1463 | r5c_flush_cache(conf, num: stripes_to_flush); |
1464 | spin_unlock_irqrestore(lock: &conf->device_lock, flags); |
1465 | } |
1466 | |
1467 | /* if log space is tight, flush stripes on stripe_in_journal_list */ |
1468 | if (test_bit(R5C_LOG_TIGHT, &conf->cache_state)) { |
1469 | spin_lock_irqsave(&log->stripe_in_journal_lock, flags); |
1470 | spin_lock(lock: &conf->device_lock); |
1471 | list_for_each_entry(sh, &log->stripe_in_journal_list, r5c) { |
1472 | /* |
1473 | * stripes on stripe_in_journal_list could be in any |
1474 | * state of the stripe_cache state machine. In this |
1475 | * case, we only want to flush stripe on |
1476 | * r5c_cached_full/partial_stripes. The following |
1477 | * condition makes sure the stripe is on one of the |
1478 | * two lists. |
1479 | */ |
1480 | if (!list_empty(head: &sh->lru) && |
1481 | !test_bit(STRIPE_HANDLE, &sh->state) && |
1482 | atomic_read(v: &sh->count) == 0) { |
1483 | r5c_flush_stripe(conf, sh); |
1484 | if (count++ >= R5C_RECLAIM_STRIPE_GROUP) |
1485 | break; |
1486 | } |
1487 | } |
1488 | spin_unlock(lock: &conf->device_lock); |
1489 | spin_unlock_irqrestore(lock: &log->stripe_in_journal_lock, flags); |
1490 | } |
1491 | |
1492 | if (!test_bit(R5C_LOG_CRITICAL, &conf->cache_state)) |
1493 | r5l_run_no_space_stripes(log); |
1494 | |
1495 | md_wakeup_thread(thread: conf->mddev->thread); |
1496 | } |
1497 | |
1498 | static void r5l_do_reclaim(struct r5l_log *log) |
1499 | { |
1500 | struct r5conf *conf = log->rdev->mddev->private; |
1501 | sector_t reclaim_target = xchg(&log->reclaim_target, 0); |
1502 | sector_t reclaimable; |
1503 | sector_t next_checkpoint; |
1504 | bool write_super; |
1505 | |
1506 | spin_lock_irq(lock: &log->io_list_lock); |
1507 | write_super = r5l_reclaimable_space(log) > log->max_free_space || |
1508 | reclaim_target != 0 || !list_empty(head: &log->no_space_stripes); |
1509 | /* |
1510 | * move proper io_unit to reclaim list. We should not change the order. |
1511 | * reclaimable/unreclaimable io_unit can be mixed in the list, we |
1512 | * shouldn't reuse space of an unreclaimable io_unit |
1513 | */ |
1514 | while (1) { |
1515 | reclaimable = r5l_reclaimable_space(log); |
1516 | if (reclaimable >= reclaim_target || |
1517 | (list_empty(head: &log->running_ios) && |
1518 | list_empty(head: &log->io_end_ios) && |
1519 | list_empty(head: &log->flushing_ios) && |
1520 | list_empty(head: &log->finished_ios))) |
1521 | break; |
1522 | |
1523 | md_wakeup_thread(thread: log->rdev->mddev->thread); |
1524 | wait_event_lock_irq(log->iounit_wait, |
1525 | r5l_reclaimable_space(log) > reclaimable, |
1526 | log->io_list_lock); |
1527 | } |
1528 | |
1529 | next_checkpoint = r5c_calculate_new_cp(conf); |
1530 | spin_unlock_irq(lock: &log->io_list_lock); |
1531 | |
1532 | if (reclaimable == 0 || !write_super) |
1533 | return; |
1534 | |
1535 | /* |
1536 | * write_super will flush cache of each raid disk. We must write super |
1537 | * here, because the log area might be reused soon and we don't want to |
1538 | * confuse recovery |
1539 | */ |
1540 | r5l_write_super_and_discard_space(log, end: next_checkpoint); |
1541 | |
1542 | mutex_lock(&log->io_mutex); |
1543 | log->last_checkpoint = next_checkpoint; |
1544 | r5c_update_log_state(log); |
1545 | mutex_unlock(lock: &log->io_mutex); |
1546 | |
1547 | r5l_run_no_space_stripes(log); |
1548 | } |
1549 | |
1550 | static void r5l_reclaim_thread(struct md_thread *thread) |
1551 | { |
1552 | struct mddev *mddev = thread->mddev; |
1553 | struct r5conf *conf = mddev->private; |
1554 | struct r5l_log *log = READ_ONCE(conf->log); |
1555 | |
1556 | if (!log) |
1557 | return; |
1558 | r5c_do_reclaim(conf); |
1559 | r5l_do_reclaim(log); |
1560 | } |
1561 | |
1562 | void r5l_wake_reclaim(struct r5l_log *log, sector_t space) |
1563 | { |
1564 | unsigned long target; |
1565 | unsigned long new = (unsigned long)space; /* overflow in theory */ |
1566 | |
1567 | if (!log) |
1568 | return; |
1569 | |
1570 | target = READ_ONCE(log->reclaim_target); |
1571 | do { |
1572 | if (new < target) |
1573 | return; |
1574 | } while (!try_cmpxchg(&log->reclaim_target, &target, new)); |
1575 | md_wakeup_thread(thread: log->reclaim_thread); |
1576 | } |
1577 | |
1578 | void r5l_quiesce(struct r5l_log *log, int quiesce) |
1579 | { |
1580 | struct mddev *mddev = log->rdev->mddev; |
1581 | struct md_thread *thread = rcu_dereference_protected( |
1582 | log->reclaim_thread, lockdep_is_held(&mddev->reconfig_mutex)); |
1583 | |
1584 | if (quiesce) { |
1585 | /* make sure r5l_write_super_and_discard_space exits */ |
1586 | wake_up(&mddev->sb_wait); |
1587 | kthread_park(k: thread->tsk); |
1588 | r5l_wake_reclaim(log, MaxSector); |
1589 | r5l_do_reclaim(log); |
1590 | } else |
1591 | kthread_unpark(k: thread->tsk); |
1592 | } |
1593 | |
1594 | bool r5l_log_disk_error(struct r5conf *conf) |
1595 | { |
1596 | struct r5l_log *log = READ_ONCE(conf->log); |
1597 | |
1598 | /* don't allow write if journal disk is missing */ |
1599 | if (!log) |
1600 | return test_bit(MD_HAS_JOURNAL, &conf->mddev->flags); |
1601 | else |
1602 | return test_bit(Faulty, &log->rdev->flags); |
1603 | } |
1604 | |
1605 | #define R5L_RECOVERY_PAGE_POOL_SIZE 256 |
1606 | |
1607 | struct r5l_recovery_ctx { |
1608 | struct page *meta_page; /* current meta */ |
1609 | sector_t meta_total_blocks; /* total size of current meta and data */ |
1610 | sector_t pos; /* recovery position */ |
1611 | u64 seq; /* recovery position seq */ |
1612 | int data_parity_stripes; /* number of data_parity stripes */ |
1613 | int data_only_stripes; /* number of data_only stripes */ |
1614 | struct list_head cached_list; |
1615 | |
1616 | /* |
1617 | * read ahead page pool (ra_pool) |
1618 | * in recovery, log is read sequentially. It is not efficient to |
1619 | * read every page with sync_page_io(). The read ahead page pool |
1620 | * reads multiple pages with one IO, so further log read can |
1621 | * just copy data from the pool. |
1622 | */ |
1623 | struct page *ra_pool[R5L_RECOVERY_PAGE_POOL_SIZE]; |
1624 | struct bio_vec ra_bvec[R5L_RECOVERY_PAGE_POOL_SIZE]; |
1625 | sector_t pool_offset; /* offset of first page in the pool */ |
1626 | int total_pages; /* total allocated pages */ |
1627 | int valid_pages; /* pages with valid data */ |
1628 | }; |
1629 | |
1630 | static int r5l_recovery_allocate_ra_pool(struct r5l_log *log, |
1631 | struct r5l_recovery_ctx *ctx) |
1632 | { |
1633 | struct page *page; |
1634 | |
1635 | ctx->valid_pages = 0; |
1636 | ctx->total_pages = 0; |
1637 | while (ctx->total_pages < R5L_RECOVERY_PAGE_POOL_SIZE) { |
1638 | page = alloc_page(GFP_KERNEL); |
1639 | |
1640 | if (!page) |
1641 | break; |
1642 | ctx->ra_pool[ctx->total_pages] = page; |
1643 | ctx->total_pages += 1; |
1644 | } |
1645 | |
1646 | if (ctx->total_pages == 0) |
1647 | return -ENOMEM; |
1648 | |
1649 | ctx->pool_offset = 0; |
1650 | return 0; |
1651 | } |
1652 | |
1653 | static void r5l_recovery_free_ra_pool(struct r5l_log *log, |
1654 | struct r5l_recovery_ctx *ctx) |
1655 | { |
1656 | int i; |
1657 | |
1658 | for (i = 0; i < ctx->total_pages; ++i) |
1659 | put_page(page: ctx->ra_pool[i]); |
1660 | } |
1661 | |
1662 | /* |
1663 | * fetch ctx->valid_pages pages from offset |
1664 | * In normal cases, ctx->valid_pages == ctx->total_pages after the call. |
1665 | * However, if the offset is close to the end of the journal device, |
1666 | * ctx->valid_pages could be smaller than ctx->total_pages |
1667 | */ |
1668 | static int r5l_recovery_fetch_ra_pool(struct r5l_log *log, |
1669 | struct r5l_recovery_ctx *ctx, |
1670 | sector_t offset) |
1671 | { |
1672 | struct bio bio; |
1673 | int ret; |
1674 | |
1675 | bio_init(bio: &bio, bdev: log->rdev->bdev, table: ctx->ra_bvec, |
1676 | R5L_RECOVERY_PAGE_POOL_SIZE, opf: REQ_OP_READ); |
1677 | bio.bi_iter.bi_sector = log->rdev->data_offset + offset; |
1678 | |
1679 | ctx->valid_pages = 0; |
1680 | ctx->pool_offset = offset; |
1681 | |
1682 | while (ctx->valid_pages < ctx->total_pages) { |
1683 | __bio_add_page(bio: &bio, page: ctx->ra_pool[ctx->valid_pages], PAGE_SIZE, |
1684 | off: 0); |
1685 | ctx->valid_pages += 1; |
1686 | |
1687 | offset = r5l_ring_add(log, start: offset, BLOCK_SECTORS); |
1688 | |
1689 | if (offset == 0) /* reached end of the device */ |
1690 | break; |
1691 | } |
1692 | |
1693 | ret = submit_bio_wait(bio: &bio); |
1694 | bio_uninit(&bio); |
1695 | return ret; |
1696 | } |
1697 | |
1698 | /* |
1699 | * try read a page from the read ahead page pool, if the page is not in the |
1700 | * pool, call r5l_recovery_fetch_ra_pool |
1701 | */ |
1702 | static int r5l_recovery_read_page(struct r5l_log *log, |
1703 | struct r5l_recovery_ctx *ctx, |
1704 | struct page *page, |
1705 | sector_t offset) |
1706 | { |
1707 | int ret; |
1708 | |
1709 | if (offset < ctx->pool_offset || |
1710 | offset >= ctx->pool_offset + ctx->valid_pages * BLOCK_SECTORS) { |
1711 | ret = r5l_recovery_fetch_ra_pool(log, ctx, offset); |
1712 | if (ret) |
1713 | return ret; |
1714 | } |
1715 | |
1716 | BUG_ON(offset < ctx->pool_offset || |
1717 | offset >= ctx->pool_offset + ctx->valid_pages * BLOCK_SECTORS); |
1718 | |
1719 | memcpy(page_address(page), |
1720 | page_address(ctx->ra_pool[(offset - ctx->pool_offset) >> |
1721 | BLOCK_SECTOR_SHIFT]), |
1722 | PAGE_SIZE); |
1723 | return 0; |
1724 | } |
1725 | |
1726 | static int r5l_recovery_read_meta_block(struct r5l_log *log, |
1727 | struct r5l_recovery_ctx *ctx) |
1728 | { |
1729 | struct page *page = ctx->meta_page; |
1730 | struct r5l_meta_block *mb; |
1731 | u32 crc, stored_crc; |
1732 | int ret; |
1733 | |
1734 | ret = r5l_recovery_read_page(log, ctx, page, offset: ctx->pos); |
1735 | if (ret != 0) |
1736 | return ret; |
1737 | |
1738 | mb = page_address(page); |
1739 | stored_crc = le32_to_cpu(mb->checksum); |
1740 | mb->checksum = 0; |
1741 | |
1742 | if (le32_to_cpu(mb->magic) != R5LOG_MAGIC || |
1743 | le64_to_cpu(mb->seq) != ctx->seq || |
1744 | mb->version != R5LOG_VERSION || |
1745 | le64_to_cpu(mb->position) != ctx->pos) |
1746 | return -EINVAL; |
1747 | |
1748 | crc = crc32c_le(crc: log->uuid_checksum, address: mb, PAGE_SIZE); |
1749 | if (stored_crc != crc) |
1750 | return -EINVAL; |
1751 | |
1752 | if (le32_to_cpu(mb->meta_size) > PAGE_SIZE) |
1753 | return -EINVAL; |
1754 | |
1755 | ctx->meta_total_blocks = BLOCK_SECTORS; |
1756 | |
1757 | return 0; |
1758 | } |
1759 | |
1760 | static void |
1761 | r5l_recovery_create_empty_meta_block(struct r5l_log *log, |
1762 | struct page *page, |
1763 | sector_t pos, u64 seq) |
1764 | { |
1765 | struct r5l_meta_block *mb; |
1766 | |
1767 | mb = page_address(page); |
1768 | clear_page(page: mb); |
1769 | mb->magic = cpu_to_le32(R5LOG_MAGIC); |
1770 | mb->version = R5LOG_VERSION; |
1771 | mb->meta_size = cpu_to_le32(sizeof(struct r5l_meta_block)); |
1772 | mb->seq = cpu_to_le64(seq); |
1773 | mb->position = cpu_to_le64(pos); |
1774 | } |
1775 | |
1776 | static int r5l_log_write_empty_meta_block(struct r5l_log *log, sector_t pos, |
1777 | u64 seq) |
1778 | { |
1779 | struct page *page; |
1780 | struct r5l_meta_block *mb; |
1781 | |
1782 | page = alloc_page(GFP_KERNEL); |
1783 | if (!page) |
1784 | return -ENOMEM; |
1785 | r5l_recovery_create_empty_meta_block(log, page, pos, seq); |
1786 | mb = page_address(page); |
1787 | mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum, |
1788 | mb, PAGE_SIZE)); |
1789 | if (!sync_page_io(rdev: log->rdev, sector: pos, PAGE_SIZE, page, opf: REQ_OP_WRITE | |
1790 | REQ_SYNC | REQ_FUA, metadata_op: false)) { |
1791 | __free_page(page); |
1792 | return -EIO; |
1793 | } |
1794 | __free_page(page); |
1795 | return 0; |
1796 | } |
1797 | |
1798 | /* |
1799 | * r5l_recovery_load_data and r5l_recovery_load_parity uses flag R5_Wantwrite |
1800 | * to mark valid (potentially not flushed) data in the journal. |
1801 | * |
1802 | * We already verified checksum in r5l_recovery_verify_data_checksum_for_mb, |
1803 | * so there should not be any mismatch here. |
1804 | */ |
1805 | static void r5l_recovery_load_data(struct r5l_log *log, |
1806 | struct stripe_head *sh, |
1807 | struct r5l_recovery_ctx *ctx, |
1808 | struct r5l_payload_data_parity *payload, |
1809 | sector_t log_offset) |
1810 | { |
1811 | struct mddev *mddev = log->rdev->mddev; |
1812 | struct r5conf *conf = mddev->private; |
1813 | int dd_idx; |
1814 | |
1815 | raid5_compute_sector(conf, |
1816 | le64_to_cpu(payload->location), previous: 0, |
1817 | dd_idx: &dd_idx, sh); |
1818 | r5l_recovery_read_page(log, ctx, page: sh->dev[dd_idx].page, offset: log_offset); |
1819 | sh->dev[dd_idx].log_checksum = |
1820 | le32_to_cpu(payload->checksum[0]); |
1821 | ctx->meta_total_blocks += BLOCK_SECTORS; |
1822 | |
1823 | set_bit(nr: R5_Wantwrite, addr: &sh->dev[dd_idx].flags); |
1824 | set_bit(nr: STRIPE_R5C_CACHING, addr: &sh->state); |
1825 | } |
1826 | |
1827 | static void r5l_recovery_load_parity(struct r5l_log *log, |
1828 | struct stripe_head *sh, |
1829 | struct r5l_recovery_ctx *ctx, |
1830 | struct r5l_payload_data_parity *payload, |
1831 | sector_t log_offset) |
1832 | { |
1833 | struct mddev *mddev = log->rdev->mddev; |
1834 | struct r5conf *conf = mddev->private; |
1835 | |
1836 | ctx->meta_total_blocks += BLOCK_SECTORS * conf->max_degraded; |
1837 | r5l_recovery_read_page(log, ctx, page: sh->dev[sh->pd_idx].page, offset: log_offset); |
1838 | sh->dev[sh->pd_idx].log_checksum = |
1839 | le32_to_cpu(payload->checksum[0]); |
1840 | set_bit(nr: R5_Wantwrite, addr: &sh->dev[sh->pd_idx].flags); |
1841 | |
1842 | if (sh->qd_idx >= 0) { |
1843 | r5l_recovery_read_page( |
1844 | log, ctx, page: sh->dev[sh->qd_idx].page, |
1845 | offset: r5l_ring_add(log, start: log_offset, BLOCK_SECTORS)); |
1846 | sh->dev[sh->qd_idx].log_checksum = |
1847 | le32_to_cpu(payload->checksum[1]); |
1848 | set_bit(nr: R5_Wantwrite, addr: &sh->dev[sh->qd_idx].flags); |
1849 | } |
1850 | clear_bit(nr: STRIPE_R5C_CACHING, addr: &sh->state); |
1851 | } |
1852 | |
1853 | static void r5l_recovery_reset_stripe(struct stripe_head *sh) |
1854 | { |
1855 | int i; |
1856 | |
1857 | sh->state = 0; |
1858 | sh->log_start = MaxSector; |
1859 | for (i = sh->disks; i--; ) |
1860 | sh->dev[i].flags = 0; |
1861 | } |
1862 | |
1863 | static void |
1864 | r5l_recovery_replay_one_stripe(struct r5conf *conf, |
1865 | struct stripe_head *sh, |
1866 | struct r5l_recovery_ctx *ctx) |
1867 | { |
1868 | struct md_rdev *rdev, *rrdev; |
1869 | int disk_index; |
1870 | int data_count = 0; |
1871 | |
1872 | for (disk_index = 0; disk_index < sh->disks; disk_index++) { |
1873 | if (!test_bit(R5_Wantwrite, &sh->dev[disk_index].flags)) |
1874 | continue; |
1875 | if (disk_index == sh->qd_idx || disk_index == sh->pd_idx) |
1876 | continue; |
1877 | data_count++; |
1878 | } |
1879 | |
1880 | /* |
1881 | * stripes that only have parity must have been flushed |
1882 | * before the crash that we are now recovering from, so |
1883 | * there is nothing more to recovery. |
1884 | */ |
1885 | if (data_count == 0) |
1886 | goto out; |
1887 | |
1888 | for (disk_index = 0; disk_index < sh->disks; disk_index++) { |
1889 | if (!test_bit(R5_Wantwrite, &sh->dev[disk_index].flags)) |
1890 | continue; |
1891 | |
1892 | /* in case device is broken */ |
1893 | rcu_read_lock(); |
1894 | rdev = rcu_dereference(conf->disks[disk_index].rdev); |
1895 | if (rdev) { |
1896 | atomic_inc(v: &rdev->nr_pending); |
1897 | rcu_read_unlock(); |
1898 | sync_page_io(rdev, sector: sh->sector, PAGE_SIZE, |
1899 | page: sh->dev[disk_index].page, opf: REQ_OP_WRITE, |
1900 | metadata_op: false); |
1901 | rdev_dec_pending(rdev, mddev: rdev->mddev); |
1902 | rcu_read_lock(); |
1903 | } |
1904 | rrdev = rcu_dereference(conf->disks[disk_index].replacement); |
1905 | if (rrdev) { |
1906 | atomic_inc(v: &rrdev->nr_pending); |
1907 | rcu_read_unlock(); |
1908 | sync_page_io(rdev: rrdev, sector: sh->sector, PAGE_SIZE, |
1909 | page: sh->dev[disk_index].page, opf: REQ_OP_WRITE, |
1910 | metadata_op: false); |
1911 | rdev_dec_pending(rdev: rrdev, mddev: rrdev->mddev); |
1912 | rcu_read_lock(); |
1913 | } |
1914 | rcu_read_unlock(); |
1915 | } |
1916 | ctx->data_parity_stripes++; |
1917 | out: |
1918 | r5l_recovery_reset_stripe(sh); |
1919 | } |
1920 | |
1921 | static struct stripe_head * |
1922 | r5c_recovery_alloc_stripe( |
1923 | struct r5conf *conf, |
1924 | sector_t stripe_sect, |
1925 | int noblock) |
1926 | { |
1927 | struct stripe_head *sh; |
1928 | |
1929 | sh = raid5_get_active_stripe(conf, NULL, sector: stripe_sect, |
1930 | flags: noblock ? R5_GAS_NOBLOCK : 0); |
1931 | if (!sh) |
1932 | return NULL; /* no more stripe available */ |
1933 | |
1934 | r5l_recovery_reset_stripe(sh); |
1935 | |
1936 | return sh; |
1937 | } |
1938 | |
1939 | static struct stripe_head * |
1940 | r5c_recovery_lookup_stripe(struct list_head *list, sector_t sect) |
1941 | { |
1942 | struct stripe_head *sh; |
1943 | |
1944 | list_for_each_entry(sh, list, lru) |
1945 | if (sh->sector == sect) |
1946 | return sh; |
1947 | return NULL; |
1948 | } |
1949 | |
1950 | static void |
1951 | r5c_recovery_drop_stripes(struct list_head *cached_stripe_list, |
1952 | struct r5l_recovery_ctx *ctx) |
1953 | { |
1954 | struct stripe_head *sh, *next; |
1955 | |
1956 | list_for_each_entry_safe(sh, next, cached_stripe_list, lru) { |
1957 | r5l_recovery_reset_stripe(sh); |
1958 | list_del_init(entry: &sh->lru); |
1959 | raid5_release_stripe(sh); |
1960 | } |
1961 | } |
1962 | |
1963 | static void |
1964 | r5c_recovery_replay_stripes(struct list_head *cached_stripe_list, |
1965 | struct r5l_recovery_ctx *ctx) |
1966 | { |
1967 | struct stripe_head *sh, *next; |
1968 | |
1969 | list_for_each_entry_safe(sh, next, cached_stripe_list, lru) |
1970 | if (!test_bit(STRIPE_R5C_CACHING, &sh->state)) { |
1971 | r5l_recovery_replay_one_stripe(conf: sh->raid_conf, sh, ctx); |
1972 | list_del_init(entry: &sh->lru); |
1973 | raid5_release_stripe(sh); |
1974 | } |
1975 | } |
1976 | |
1977 | /* if matches return 0; otherwise return -EINVAL */ |
1978 | static int |
1979 | r5l_recovery_verify_data_checksum(struct r5l_log *log, |
1980 | struct r5l_recovery_ctx *ctx, |
1981 | struct page *page, |
1982 | sector_t log_offset, __le32 log_checksum) |
1983 | { |
1984 | void *addr; |
1985 | u32 checksum; |
1986 | |
1987 | r5l_recovery_read_page(log, ctx, page, offset: log_offset); |
1988 | addr = kmap_atomic(page); |
1989 | checksum = crc32c_le(crc: log->uuid_checksum, address: addr, PAGE_SIZE); |
1990 | kunmap_atomic(addr); |
1991 | return (le32_to_cpu(log_checksum) == checksum) ? 0 : -EINVAL; |
1992 | } |
1993 | |
1994 | /* |
1995 | * before loading data to stripe cache, we need verify checksum for all data, |
1996 | * if there is mismatch for any data page, we drop all data in the mata block |
1997 | */ |
1998 | static int |
1999 | r5l_recovery_verify_data_checksum_for_mb(struct r5l_log *log, |
2000 | struct r5l_recovery_ctx *ctx) |
2001 | { |
2002 | struct mddev *mddev = log->rdev->mddev; |
2003 | struct r5conf *conf = mddev->private; |
2004 | struct r5l_meta_block *mb = page_address(ctx->meta_page); |
2005 | sector_t mb_offset = sizeof(struct r5l_meta_block); |
2006 | sector_t log_offset = r5l_ring_add(log, start: ctx->pos, BLOCK_SECTORS); |
2007 | struct page *page; |
2008 | struct r5l_payload_data_parity *payload; |
2009 | struct r5l_payload_flush *payload_flush; |
2010 | |
2011 | page = alloc_page(GFP_KERNEL); |
2012 | if (!page) |
2013 | return -ENOMEM; |
2014 | |
2015 | while (mb_offset < le32_to_cpu(mb->meta_size)) { |
2016 | payload = (void *)mb + mb_offset; |
2017 | payload_flush = (void *)mb + mb_offset; |
2018 | |
2019 | if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) { |
2020 | if (r5l_recovery_verify_data_checksum( |
2021 | log, ctx, page, log_offset, |
2022 | log_checksum: payload->checksum[0]) < 0) |
2023 | goto mismatch; |
2024 | } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_PARITY) { |
2025 | if (r5l_recovery_verify_data_checksum( |
2026 | log, ctx, page, log_offset, |
2027 | log_checksum: payload->checksum[0]) < 0) |
2028 | goto mismatch; |
2029 | if (conf->max_degraded == 2 && /* q for RAID 6 */ |
2030 | r5l_recovery_verify_data_checksum( |
2031 | log, ctx, page, |
2032 | log_offset: r5l_ring_add(log, start: log_offset, |
2033 | BLOCK_SECTORS), |
2034 | log_checksum: payload->checksum[1]) < 0) |
2035 | goto mismatch; |
2036 | } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) { |
2037 | /* nothing to do for R5LOG_PAYLOAD_FLUSH here */ |
2038 | } else /* not R5LOG_PAYLOAD_DATA/PARITY/FLUSH */ |
2039 | goto mismatch; |
2040 | |
2041 | if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) { |
2042 | mb_offset += sizeof(struct r5l_payload_flush) + |
2043 | le32_to_cpu(payload_flush->size); |
2044 | } else { |
2045 | /* DATA or PARITY payload */ |
2046 | log_offset = r5l_ring_add(log, start: log_offset, |
2047 | le32_to_cpu(payload->size)); |
2048 | mb_offset += sizeof(struct r5l_payload_data_parity) + |
2049 | sizeof(__le32) * |
2050 | (le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9)); |
2051 | } |
2052 | |
2053 | } |
2054 | |
2055 | put_page(page); |
2056 | return 0; |
2057 | |
2058 | mismatch: |
2059 | put_page(page); |
2060 | return -EINVAL; |
2061 | } |
2062 | |
2063 | /* |
2064 | * Analyze all data/parity pages in one meta block |
2065 | * Returns: |
2066 | * 0 for success |
2067 | * -EINVAL for unknown playload type |
2068 | * -EAGAIN for checksum mismatch of data page |
2069 | * -ENOMEM for run out of memory (alloc_page failed or run out of stripes) |
2070 | */ |
2071 | static int |
2072 | r5c_recovery_analyze_meta_block(struct r5l_log *log, |
2073 | struct r5l_recovery_ctx *ctx, |
2074 | struct list_head *cached_stripe_list) |
2075 | { |
2076 | struct mddev *mddev = log->rdev->mddev; |
2077 | struct r5conf *conf = mddev->private; |
2078 | struct r5l_meta_block *mb; |
2079 | struct r5l_payload_data_parity *payload; |
2080 | struct r5l_payload_flush *payload_flush; |
2081 | int mb_offset; |
2082 | sector_t log_offset; |
2083 | sector_t stripe_sect; |
2084 | struct stripe_head *sh; |
2085 | int ret; |
2086 | |
2087 | /* |
2088 | * for mismatch in data blocks, we will drop all data in this mb, but |
2089 | * we will still read next mb for other data with FLUSH flag, as |
2090 | * io_unit could finish out of order. |
2091 | */ |
2092 | ret = r5l_recovery_verify_data_checksum_for_mb(log, ctx); |
2093 | if (ret == -EINVAL) |
2094 | return -EAGAIN; |
2095 | else if (ret) |
2096 | return ret; /* -ENOMEM duo to alloc_page() failed */ |
2097 | |
2098 | mb = page_address(ctx->meta_page); |
2099 | mb_offset = sizeof(struct r5l_meta_block); |
2100 | log_offset = r5l_ring_add(log, start: ctx->pos, BLOCK_SECTORS); |
2101 | |
2102 | while (mb_offset < le32_to_cpu(mb->meta_size)) { |
2103 | int dd; |
2104 | |
2105 | payload = (void *)mb + mb_offset; |
2106 | payload_flush = (void *)mb + mb_offset; |
2107 | |
2108 | if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_FLUSH) { |
2109 | int i, count; |
2110 | |
2111 | count = le32_to_cpu(payload_flush->size) / sizeof(__le64); |
2112 | for (i = 0; i < count; ++i) { |
2113 | stripe_sect = le64_to_cpu(payload_flush->flush_stripes[i]); |
2114 | sh = r5c_recovery_lookup_stripe(list: cached_stripe_list, |
2115 | sect: stripe_sect); |
2116 | if (sh) { |
2117 | WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state)); |
2118 | r5l_recovery_reset_stripe(sh); |
2119 | list_del_init(entry: &sh->lru); |
2120 | raid5_release_stripe(sh); |
2121 | } |
2122 | } |
2123 | |
2124 | mb_offset += sizeof(struct r5l_payload_flush) + |
2125 | le32_to_cpu(payload_flush->size); |
2126 | continue; |
2127 | } |
2128 | |
2129 | /* DATA or PARITY payload */ |
2130 | stripe_sect = (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) ? |
2131 | raid5_compute_sector( |
2132 | conf, le64_to_cpu(payload->location), previous: 0, dd_idx: &dd, |
2133 | NULL) |
2134 | : le64_to_cpu(payload->location); |
2135 | |
2136 | sh = r5c_recovery_lookup_stripe(list: cached_stripe_list, |
2137 | sect: stripe_sect); |
2138 | |
2139 | if (!sh) { |
2140 | sh = r5c_recovery_alloc_stripe(conf, stripe_sect, noblock: 1); |
2141 | /* |
2142 | * cannot get stripe from raid5_get_active_stripe |
2143 | * try replay some stripes |
2144 | */ |
2145 | if (!sh) { |
2146 | r5c_recovery_replay_stripes( |
2147 | cached_stripe_list, ctx); |
2148 | sh = r5c_recovery_alloc_stripe( |
2149 | conf, stripe_sect, noblock: 1); |
2150 | } |
2151 | if (!sh) { |
2152 | int new_size = conf->min_nr_stripes * 2; |
2153 | pr_debug("md/raid:%s: Increasing stripe cache size to %d to recovery data on journal.\n" , |
2154 | mdname(mddev), |
2155 | new_size); |
2156 | ret = raid5_set_cache_size(mddev, size: new_size); |
2157 | if (conf->min_nr_stripes <= new_size / 2) { |
2158 | pr_err("md/raid:%s: Cannot increase cache size, ret=%d, new_size=%d, min_nr_stripes=%d, max_nr_stripes=%d\n" , |
2159 | mdname(mddev), |
2160 | ret, |
2161 | new_size, |
2162 | conf->min_nr_stripes, |
2163 | conf->max_nr_stripes); |
2164 | return -ENOMEM; |
2165 | } |
2166 | sh = r5c_recovery_alloc_stripe( |
2167 | conf, stripe_sect, noblock: 0); |
2168 | } |
2169 | if (!sh) { |
2170 | pr_err("md/raid:%s: Cannot get enough stripes due to memory pressure. Recovery failed.\n" , |
2171 | mdname(mddev)); |
2172 | return -ENOMEM; |
2173 | } |
2174 | list_add_tail(new: &sh->lru, head: cached_stripe_list); |
2175 | } |
2176 | |
2177 | if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_DATA) { |
2178 | if (!test_bit(STRIPE_R5C_CACHING, &sh->state) && |
2179 | test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags)) { |
2180 | r5l_recovery_replay_one_stripe(conf, sh, ctx); |
2181 | list_move_tail(list: &sh->lru, head: cached_stripe_list); |
2182 | } |
2183 | r5l_recovery_load_data(log, sh, ctx, payload, |
2184 | log_offset); |
2185 | } else if (le16_to_cpu(payload->header.type) == R5LOG_PAYLOAD_PARITY) |
2186 | r5l_recovery_load_parity(log, sh, ctx, payload, |
2187 | log_offset); |
2188 | else |
2189 | return -EINVAL; |
2190 | |
2191 | log_offset = r5l_ring_add(log, start: log_offset, |
2192 | le32_to_cpu(payload->size)); |
2193 | |
2194 | mb_offset += sizeof(struct r5l_payload_data_parity) + |
2195 | sizeof(__le32) * |
2196 | (le32_to_cpu(payload->size) >> (PAGE_SHIFT - 9)); |
2197 | } |
2198 | |
2199 | return 0; |
2200 | } |
2201 | |
2202 | /* |
2203 | * Load the stripe into cache. The stripe will be written out later by |
2204 | * the stripe cache state machine. |
2205 | */ |
2206 | static void r5c_recovery_load_one_stripe(struct r5l_log *log, |
2207 | struct stripe_head *sh) |
2208 | { |
2209 | struct r5dev *dev; |
2210 | int i; |
2211 | |
2212 | for (i = sh->disks; i--; ) { |
2213 | dev = sh->dev + i; |
2214 | if (test_and_clear_bit(nr: R5_Wantwrite, addr: &dev->flags)) { |
2215 | set_bit(nr: R5_InJournal, addr: &dev->flags); |
2216 | set_bit(nr: R5_UPTODATE, addr: &dev->flags); |
2217 | } |
2218 | } |
2219 | } |
2220 | |
2221 | /* |
2222 | * Scan through the log for all to-be-flushed data |
2223 | * |
2224 | * For stripes with data and parity, namely Data-Parity stripe |
2225 | * (STRIPE_R5C_CACHING == 0), we simply replay all the writes. |
2226 | * |
2227 | * For stripes with only data, namely Data-Only stripe |
2228 | * (STRIPE_R5C_CACHING == 1), we load them to stripe cache state machine. |
2229 | * |
2230 | * For a stripe, if we see data after parity, we should discard all previous |
2231 | * data and parity for this stripe, as these data are already flushed to |
2232 | * the array. |
2233 | * |
2234 | * At the end of the scan, we return the new journal_tail, which points to |
2235 | * first data-only stripe on the journal device, or next invalid meta block. |
2236 | */ |
2237 | static int r5c_recovery_flush_log(struct r5l_log *log, |
2238 | struct r5l_recovery_ctx *ctx) |
2239 | { |
2240 | struct stripe_head *sh; |
2241 | int ret = 0; |
2242 | |
2243 | /* scan through the log */ |
2244 | while (1) { |
2245 | if (r5l_recovery_read_meta_block(log, ctx)) |
2246 | break; |
2247 | |
2248 | ret = r5c_recovery_analyze_meta_block(log, ctx, |
2249 | cached_stripe_list: &ctx->cached_list); |
2250 | /* |
2251 | * -EAGAIN means mismatch in data block, in this case, we still |
2252 | * try scan the next metablock |
2253 | */ |
2254 | if (ret && ret != -EAGAIN) |
2255 | break; /* ret == -EINVAL or -ENOMEM */ |
2256 | ctx->seq++; |
2257 | ctx->pos = r5l_ring_add(log, start: ctx->pos, inc: ctx->meta_total_blocks); |
2258 | } |
2259 | |
2260 | if (ret == -ENOMEM) { |
2261 | r5c_recovery_drop_stripes(cached_stripe_list: &ctx->cached_list, ctx); |
2262 | return ret; |
2263 | } |
2264 | |
2265 | /* replay data-parity stripes */ |
2266 | r5c_recovery_replay_stripes(cached_stripe_list: &ctx->cached_list, ctx); |
2267 | |
2268 | /* load data-only stripes to stripe cache */ |
2269 | list_for_each_entry(sh, &ctx->cached_list, lru) { |
2270 | WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state)); |
2271 | r5c_recovery_load_one_stripe(log, sh); |
2272 | ctx->data_only_stripes++; |
2273 | } |
2274 | |
2275 | return 0; |
2276 | } |
2277 | |
2278 | /* |
2279 | * we did a recovery. Now ctx.pos points to an invalid meta block. New |
2280 | * log will start here. but we can't let superblock point to last valid |
2281 | * meta block. The log might looks like: |
2282 | * | meta 1| meta 2| meta 3| |
2283 | * meta 1 is valid, meta 2 is invalid. meta 3 could be valid. If |
2284 | * superblock points to meta 1, we write a new valid meta 2n. if crash |
2285 | * happens again, new recovery will start from meta 1. Since meta 2n is |
2286 | * valid now, recovery will think meta 3 is valid, which is wrong. |
2287 | * The solution is we create a new meta in meta2 with its seq == meta |
2288 | * 1's seq + 10000 and let superblock points to meta2. The same recovery |
2289 | * will not think meta 3 is a valid meta, because its seq doesn't match |
2290 | */ |
2291 | |
2292 | /* |
2293 | * Before recovery, the log looks like the following |
2294 | * |
2295 | * --------------------------------------------- |
2296 | * | valid log | invalid log | |
2297 | * --------------------------------------------- |
2298 | * ^ |
2299 | * |- log->last_checkpoint |
2300 | * |- log->last_cp_seq |
2301 | * |
2302 | * Now we scan through the log until we see invalid entry |
2303 | * |
2304 | * --------------------------------------------- |
2305 | * | valid log | invalid log | |
2306 | * --------------------------------------------- |
2307 | * ^ ^ |
2308 | * |- log->last_checkpoint |- ctx->pos |
2309 | * |- log->last_cp_seq |- ctx->seq |
2310 | * |
2311 | * From this point, we need to increase seq number by 10 to avoid |
2312 | * confusing next recovery. |
2313 | * |
2314 | * --------------------------------------------- |
2315 | * | valid log | invalid log | |
2316 | * --------------------------------------------- |
2317 | * ^ ^ |
2318 | * |- log->last_checkpoint |- ctx->pos+1 |
2319 | * |- log->last_cp_seq |- ctx->seq+10001 |
2320 | * |
2321 | * However, it is not safe to start the state machine yet, because data only |
2322 | * parities are not yet secured in RAID. To save these data only parities, we |
2323 | * rewrite them from seq+11. |
2324 | * |
2325 | * ----------------------------------------------------------------- |
2326 | * | valid log | data only stripes | invalid log | |
2327 | * ----------------------------------------------------------------- |
2328 | * ^ ^ |
2329 | * |- log->last_checkpoint |- ctx->pos+n |
2330 | * |- log->last_cp_seq |- ctx->seq+10000+n |
2331 | * |
2332 | * If failure happens again during this process, the recovery can safe start |
2333 | * again from log->last_checkpoint. |
2334 | * |
2335 | * Once data only stripes are rewritten to journal, we move log_tail |
2336 | * |
2337 | * ----------------------------------------------------------------- |
2338 | * | old log | data only stripes | invalid log | |
2339 | * ----------------------------------------------------------------- |
2340 | * ^ ^ |
2341 | * |- log->last_checkpoint |- ctx->pos+n |
2342 | * |- log->last_cp_seq |- ctx->seq+10000+n |
2343 | * |
2344 | * Then we can safely start the state machine. If failure happens from this |
2345 | * point on, the recovery will start from new log->last_checkpoint. |
2346 | */ |
2347 | static int |
2348 | r5c_recovery_rewrite_data_only_stripes(struct r5l_log *log, |
2349 | struct r5l_recovery_ctx *ctx) |
2350 | { |
2351 | struct stripe_head *sh; |
2352 | struct mddev *mddev = log->rdev->mddev; |
2353 | struct page *page; |
2354 | sector_t next_checkpoint = MaxSector; |
2355 | |
2356 | page = alloc_page(GFP_KERNEL); |
2357 | if (!page) { |
2358 | pr_err("md/raid:%s: cannot allocate memory to rewrite data only stripes\n" , |
2359 | mdname(mddev)); |
2360 | return -ENOMEM; |
2361 | } |
2362 | |
2363 | WARN_ON(list_empty(&ctx->cached_list)); |
2364 | |
2365 | list_for_each_entry(sh, &ctx->cached_list, lru) { |
2366 | struct r5l_meta_block *mb; |
2367 | int i; |
2368 | int offset; |
2369 | sector_t write_pos; |
2370 | |
2371 | WARN_ON(!test_bit(STRIPE_R5C_CACHING, &sh->state)); |
2372 | r5l_recovery_create_empty_meta_block(log, page, |
2373 | pos: ctx->pos, seq: ctx->seq); |
2374 | mb = page_address(page); |
2375 | offset = le32_to_cpu(mb->meta_size); |
2376 | write_pos = r5l_ring_add(log, start: ctx->pos, BLOCK_SECTORS); |
2377 | |
2378 | for (i = sh->disks; i--; ) { |
2379 | struct r5dev *dev = &sh->dev[i]; |
2380 | struct r5l_payload_data_parity *payload; |
2381 | void *addr; |
2382 | |
2383 | if (test_bit(R5_InJournal, &dev->flags)) { |
2384 | payload = (void *)mb + offset; |
2385 | payload->header.type = cpu_to_le16( |
2386 | R5LOG_PAYLOAD_DATA); |
2387 | payload->size = cpu_to_le32(BLOCK_SECTORS); |
2388 | payload->location = cpu_to_le64( |
2389 | raid5_compute_blocknr(sh, i, 0)); |
2390 | addr = kmap_atomic(page: dev->page); |
2391 | payload->checksum[0] = cpu_to_le32( |
2392 | crc32c_le(log->uuid_checksum, addr, |
2393 | PAGE_SIZE)); |
2394 | kunmap_atomic(addr); |
2395 | sync_page_io(rdev: log->rdev, sector: write_pos, PAGE_SIZE, |
2396 | page: dev->page, opf: REQ_OP_WRITE, metadata_op: false); |
2397 | write_pos = r5l_ring_add(log, start: write_pos, |
2398 | BLOCK_SECTORS); |
2399 | offset += sizeof(__le32) + |
2400 | sizeof(struct r5l_payload_data_parity); |
2401 | |
2402 | } |
2403 | } |
2404 | mb->meta_size = cpu_to_le32(offset); |
2405 | mb->checksum = cpu_to_le32(crc32c_le(log->uuid_checksum, |
2406 | mb, PAGE_SIZE)); |
2407 | sync_page_io(rdev: log->rdev, sector: ctx->pos, PAGE_SIZE, page, |
2408 | opf: REQ_OP_WRITE | REQ_SYNC | REQ_FUA, metadata_op: false); |
2409 | sh->log_start = ctx->pos; |
2410 | list_add_tail(new: &sh->r5c, head: &log->stripe_in_journal_list); |
2411 | atomic_inc(v: &log->stripe_in_journal_count); |
2412 | ctx->pos = write_pos; |
2413 | ctx->seq += 1; |
2414 | next_checkpoint = sh->log_start; |
2415 | } |
2416 | log->next_checkpoint = next_checkpoint; |
2417 | __free_page(page); |
2418 | return 0; |
2419 | } |
2420 | |
2421 | static void r5c_recovery_flush_data_only_stripes(struct r5l_log *log, |
2422 | struct r5l_recovery_ctx *ctx) |
2423 | { |
2424 | struct mddev *mddev = log->rdev->mddev; |
2425 | struct r5conf *conf = mddev->private; |
2426 | struct stripe_head *sh, *next; |
2427 | bool cleared_pending = false; |
2428 | |
2429 | if (ctx->data_only_stripes == 0) |
2430 | return; |
2431 | |
2432 | if (test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) { |
2433 | cleared_pending = true; |
2434 | clear_bit(nr: MD_SB_CHANGE_PENDING, addr: &mddev->sb_flags); |
2435 | } |
2436 | log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_BACK; |
2437 | |
2438 | list_for_each_entry_safe(sh, next, &ctx->cached_list, lru) { |
2439 | r5c_make_stripe_write_out(sh); |
2440 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
2441 | list_del_init(entry: &sh->lru); |
2442 | raid5_release_stripe(sh); |
2443 | } |
2444 | |
2445 | /* reuse conf->wait_for_quiescent in recovery */ |
2446 | wait_event(conf->wait_for_quiescent, |
2447 | atomic_read(&conf->active_stripes) == 0); |
2448 | |
2449 | log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH; |
2450 | if (cleared_pending) |
2451 | set_bit(nr: MD_SB_CHANGE_PENDING, addr: &mddev->sb_flags); |
2452 | } |
2453 | |
2454 | static int r5l_recovery_log(struct r5l_log *log) |
2455 | { |
2456 | struct mddev *mddev = log->rdev->mddev; |
2457 | struct r5l_recovery_ctx *ctx; |
2458 | int ret; |
2459 | sector_t pos; |
2460 | |
2461 | ctx = kzalloc(size: sizeof(*ctx), GFP_KERNEL); |
2462 | if (!ctx) |
2463 | return -ENOMEM; |
2464 | |
2465 | ctx->pos = log->last_checkpoint; |
2466 | ctx->seq = log->last_cp_seq; |
2467 | INIT_LIST_HEAD(list: &ctx->cached_list); |
2468 | ctx->meta_page = alloc_page(GFP_KERNEL); |
2469 | |
2470 | if (!ctx->meta_page) { |
2471 | ret = -ENOMEM; |
2472 | goto meta_page; |
2473 | } |
2474 | |
2475 | if (r5l_recovery_allocate_ra_pool(log, ctx) != 0) { |
2476 | ret = -ENOMEM; |
2477 | goto ra_pool; |
2478 | } |
2479 | |
2480 | ret = r5c_recovery_flush_log(log, ctx); |
2481 | |
2482 | if (ret) |
2483 | goto error; |
2484 | |
2485 | pos = ctx->pos; |
2486 | ctx->seq += 10000; |
2487 | |
2488 | if ((ctx->data_only_stripes == 0) && (ctx->data_parity_stripes == 0)) |
2489 | pr_info("md/raid:%s: starting from clean shutdown\n" , |
2490 | mdname(mddev)); |
2491 | else |
2492 | pr_info("md/raid:%s: recovering %d data-only stripes and %d data-parity stripes\n" , |
2493 | mdname(mddev), ctx->data_only_stripes, |
2494 | ctx->data_parity_stripes); |
2495 | |
2496 | if (ctx->data_only_stripes == 0) { |
2497 | log->next_checkpoint = ctx->pos; |
2498 | r5l_log_write_empty_meta_block(log, pos: ctx->pos, seq: ctx->seq++); |
2499 | ctx->pos = r5l_ring_add(log, start: ctx->pos, BLOCK_SECTORS); |
2500 | } else if (r5c_recovery_rewrite_data_only_stripes(log, ctx)) { |
2501 | pr_err("md/raid:%s: failed to rewrite stripes to journal\n" , |
2502 | mdname(mddev)); |
2503 | ret = -EIO; |
2504 | goto error; |
2505 | } |
2506 | |
2507 | log->log_start = ctx->pos; |
2508 | log->seq = ctx->seq; |
2509 | log->last_checkpoint = pos; |
2510 | r5l_write_super(log, cp: pos); |
2511 | |
2512 | r5c_recovery_flush_data_only_stripes(log, ctx); |
2513 | ret = 0; |
2514 | error: |
2515 | r5l_recovery_free_ra_pool(log, ctx); |
2516 | ra_pool: |
2517 | __free_page(ctx->meta_page); |
2518 | meta_page: |
2519 | kfree(objp: ctx); |
2520 | return ret; |
2521 | } |
2522 | |
2523 | static void r5l_write_super(struct r5l_log *log, sector_t cp) |
2524 | { |
2525 | struct mddev *mddev = log->rdev->mddev; |
2526 | |
2527 | log->rdev->journal_tail = cp; |
2528 | set_bit(nr: MD_SB_CHANGE_DEVS, addr: &mddev->sb_flags); |
2529 | } |
2530 | |
2531 | static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page) |
2532 | { |
2533 | struct r5conf *conf; |
2534 | int ret; |
2535 | |
2536 | ret = mddev_lock(mddev); |
2537 | if (ret) |
2538 | return ret; |
2539 | |
2540 | conf = mddev->private; |
2541 | if (!conf || !conf->log) |
2542 | goto out_unlock; |
2543 | |
2544 | switch (conf->log->r5c_journal_mode) { |
2545 | case R5C_JOURNAL_MODE_WRITE_THROUGH: |
2546 | ret = snprintf( |
2547 | buf: page, PAGE_SIZE, fmt: "[%s] %s\n" , |
2548 | r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_THROUGH], |
2549 | r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_BACK]); |
2550 | break; |
2551 | case R5C_JOURNAL_MODE_WRITE_BACK: |
2552 | ret = snprintf( |
2553 | buf: page, PAGE_SIZE, fmt: "%s [%s]\n" , |
2554 | r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_THROUGH], |
2555 | r5c_journal_mode_str[R5C_JOURNAL_MODE_WRITE_BACK]); |
2556 | break; |
2557 | default: |
2558 | ret = 0; |
2559 | } |
2560 | |
2561 | out_unlock: |
2562 | mddev_unlock(mddev); |
2563 | return ret; |
2564 | } |
2565 | |
2566 | /* |
2567 | * Set journal cache mode on @mddev (external API initially needed by dm-raid). |
2568 | * |
2569 | * @mode as defined in 'enum r5c_journal_mode'. |
2570 | * |
2571 | */ |
2572 | int r5c_journal_mode_set(struct mddev *mddev, int mode) |
2573 | { |
2574 | struct r5conf *conf; |
2575 | |
2576 | if (mode < R5C_JOURNAL_MODE_WRITE_THROUGH || |
2577 | mode > R5C_JOURNAL_MODE_WRITE_BACK) |
2578 | return -EINVAL; |
2579 | |
2580 | conf = mddev->private; |
2581 | if (!conf || !conf->log) |
2582 | return -ENODEV; |
2583 | |
2584 | if (raid5_calc_degraded(conf) > 0 && |
2585 | mode == R5C_JOURNAL_MODE_WRITE_BACK) |
2586 | return -EINVAL; |
2587 | |
2588 | conf->log->r5c_journal_mode = mode; |
2589 | |
2590 | pr_debug("md/raid:%s: setting r5c cache mode to %d: %s\n" , |
2591 | mdname(mddev), mode, r5c_journal_mode_str[mode]); |
2592 | return 0; |
2593 | } |
2594 | EXPORT_SYMBOL(r5c_journal_mode_set); |
2595 | |
2596 | static ssize_t r5c_journal_mode_store(struct mddev *mddev, |
2597 | const char *page, size_t length) |
2598 | { |
2599 | int mode = ARRAY_SIZE(r5c_journal_mode_str); |
2600 | size_t len = length; |
2601 | int ret; |
2602 | |
2603 | if (len < 2) |
2604 | return -EINVAL; |
2605 | |
2606 | if (page[len - 1] == '\n') |
2607 | len--; |
2608 | |
2609 | while (mode--) |
2610 | if (strlen(r5c_journal_mode_str[mode]) == len && |
2611 | !strncmp(page, r5c_journal_mode_str[mode], len)) |
2612 | break; |
2613 | ret = mddev_suspend_and_lock(mddev); |
2614 | if (ret) |
2615 | return ret; |
2616 | ret = r5c_journal_mode_set(mddev, mode); |
2617 | mddev_unlock_and_resume(mddev); |
2618 | return ret ?: length; |
2619 | } |
2620 | |
2621 | struct md_sysfs_entry |
2622 | r5c_journal_mode = __ATTR(journal_mode, 0644, |
2623 | r5c_journal_mode_show, r5c_journal_mode_store); |
2624 | |
2625 | /* |
2626 | * Try handle write operation in caching phase. This function should only |
2627 | * be called in write-back mode. |
2628 | * |
2629 | * If all outstanding writes can be handled in caching phase, returns 0 |
2630 | * If writes requires write-out phase, call r5c_make_stripe_write_out() |
2631 | * and returns -EAGAIN |
2632 | */ |
2633 | int r5c_try_caching_write(struct r5conf *conf, |
2634 | struct stripe_head *sh, |
2635 | struct stripe_head_state *s, |
2636 | int disks) |
2637 | { |
2638 | struct r5l_log *log = READ_ONCE(conf->log); |
2639 | int i; |
2640 | struct r5dev *dev; |
2641 | int to_cache = 0; |
2642 | void __rcu **pslot; |
2643 | sector_t tree_index; |
2644 | int ret; |
2645 | uintptr_t refcount; |
2646 | |
2647 | BUG_ON(!r5c_is_writeback(log)); |
2648 | |
2649 | if (!test_bit(STRIPE_R5C_CACHING, &sh->state)) { |
2650 | /* |
2651 | * There are two different scenarios here: |
2652 | * 1. The stripe has some data cached, and it is sent to |
2653 | * write-out phase for reclaim |
2654 | * 2. The stripe is clean, and this is the first write |
2655 | * |
2656 | * For 1, return -EAGAIN, so we continue with |
2657 | * handle_stripe_dirtying(). |
2658 | * |
2659 | * For 2, set STRIPE_R5C_CACHING and continue with caching |
2660 | * write. |
2661 | */ |
2662 | |
2663 | /* case 1: anything injournal or anything in written */ |
2664 | if (s->injournal > 0 || s->written > 0) |
2665 | return -EAGAIN; |
2666 | /* case 2 */ |
2667 | set_bit(nr: STRIPE_R5C_CACHING, addr: &sh->state); |
2668 | } |
2669 | |
2670 | /* |
2671 | * When run in degraded mode, array is set to write-through mode. |
2672 | * This check helps drain pending write safely in the transition to |
2673 | * write-through mode. |
2674 | * |
2675 | * When a stripe is syncing, the write is also handled in write |
2676 | * through mode. |
2677 | */ |
2678 | if (s->failed || test_bit(STRIPE_SYNCING, &sh->state)) { |
2679 | r5c_make_stripe_write_out(sh); |
2680 | return -EAGAIN; |
2681 | } |
2682 | |
2683 | for (i = disks; i--; ) { |
2684 | dev = &sh->dev[i]; |
2685 | /* if non-overwrite, use writing-out phase */ |
2686 | if (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags) && |
2687 | !test_bit(R5_InJournal, &dev->flags)) { |
2688 | r5c_make_stripe_write_out(sh); |
2689 | return -EAGAIN; |
2690 | } |
2691 | } |
2692 | |
2693 | /* if the stripe is not counted in big_stripe_tree, add it now */ |
2694 | if (!test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) && |
2695 | !test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) { |
2696 | tree_index = r5c_tree_index(conf, sect: sh->sector); |
2697 | spin_lock(lock: &log->tree_lock); |
2698 | pslot = radix_tree_lookup_slot(&log->big_stripe_tree, |
2699 | index: tree_index); |
2700 | if (pslot) { |
2701 | refcount = (uintptr_t)radix_tree_deref_slot_protected( |
2702 | slot: pslot, treelock: &log->tree_lock) >> |
2703 | R5C_RADIX_COUNT_SHIFT; |
2704 | radix_tree_replace_slot( |
2705 | &log->big_stripe_tree, slot: pslot, |
2706 | entry: (void *)((refcount + 1) << R5C_RADIX_COUNT_SHIFT)); |
2707 | } else { |
2708 | /* |
2709 | * this radix_tree_insert can fail safely, so no |
2710 | * need to call radix_tree_preload() |
2711 | */ |
2712 | ret = radix_tree_insert( |
2713 | &log->big_stripe_tree, index: tree_index, |
2714 | (void *)(1 << R5C_RADIX_COUNT_SHIFT)); |
2715 | if (ret) { |
2716 | spin_unlock(lock: &log->tree_lock); |
2717 | r5c_make_stripe_write_out(sh); |
2718 | return -EAGAIN; |
2719 | } |
2720 | } |
2721 | spin_unlock(lock: &log->tree_lock); |
2722 | |
2723 | /* |
2724 | * set STRIPE_R5C_PARTIAL_STRIPE, this shows the stripe is |
2725 | * counted in the radix tree |
2726 | */ |
2727 | set_bit(nr: STRIPE_R5C_PARTIAL_STRIPE, addr: &sh->state); |
2728 | atomic_inc(v: &conf->r5c_cached_partial_stripes); |
2729 | } |
2730 | |
2731 | for (i = disks; i--; ) { |
2732 | dev = &sh->dev[i]; |
2733 | if (dev->towrite) { |
2734 | set_bit(nr: R5_Wantwrite, addr: &dev->flags); |
2735 | set_bit(nr: R5_Wantdrain, addr: &dev->flags); |
2736 | set_bit(nr: R5_LOCKED, addr: &dev->flags); |
2737 | to_cache++; |
2738 | } |
2739 | } |
2740 | |
2741 | if (to_cache) { |
2742 | set_bit(nr: STRIPE_OP_BIODRAIN, addr: &s->ops_request); |
2743 | /* |
2744 | * set STRIPE_LOG_TRAPPED, which triggers r5c_cache_data() |
2745 | * in ops_run_io(). STRIPE_LOG_TRAPPED will be cleared in |
2746 | * r5c_handle_data_cached() |
2747 | */ |
2748 | set_bit(nr: STRIPE_LOG_TRAPPED, addr: &sh->state); |
2749 | } |
2750 | |
2751 | return 0; |
2752 | } |
2753 | |
2754 | /* |
2755 | * free extra pages (orig_page) we allocated for prexor |
2756 | */ |
2757 | void (struct stripe_head *sh) |
2758 | { |
2759 | struct r5conf *conf = sh->raid_conf; |
2760 | int i; |
2761 | bool ; |
2762 | |
2763 | using_disk_info_extra_page = |
2764 | sh->dev[0].orig_page == conf->disks[0].extra_page; |
2765 | |
2766 | for (i = sh->disks; i--; ) |
2767 | if (sh->dev[i].page != sh->dev[i].orig_page) { |
2768 | struct page *p = sh->dev[i].orig_page; |
2769 | |
2770 | sh->dev[i].orig_page = sh->dev[i].page; |
2771 | clear_bit(nr: R5_OrigPageUPTDODATE, addr: &sh->dev[i].flags); |
2772 | |
2773 | if (!using_disk_info_extra_page) |
2774 | put_page(page: p); |
2775 | } |
2776 | |
2777 | if (using_disk_info_extra_page) { |
2778 | clear_bit(nr: R5C_EXTRA_PAGE_IN_USE, addr: &conf->cache_state); |
2779 | md_wakeup_thread(thread: conf->mddev->thread); |
2780 | } |
2781 | } |
2782 | |
2783 | void (struct stripe_head *sh) |
2784 | { |
2785 | struct r5conf *conf = sh->raid_conf; |
2786 | int i; |
2787 | struct r5dev *dev; |
2788 | |
2789 | for (i = sh->disks; i--; ) { |
2790 | dev = &sh->dev[i]; |
2791 | if (dev->orig_page != dev->page) |
2792 | put_page(page: dev->orig_page); |
2793 | dev->orig_page = conf->disks[i].extra_page; |
2794 | } |
2795 | } |
2796 | |
2797 | /* |
2798 | * clean up the stripe (clear R5_InJournal for dev[pd_idx] etc.) after the |
2799 | * stripe is committed to RAID disks. |
2800 | */ |
2801 | void r5c_finish_stripe_write_out(struct r5conf *conf, |
2802 | struct stripe_head *sh, |
2803 | struct stripe_head_state *s) |
2804 | { |
2805 | struct r5l_log *log = READ_ONCE(conf->log); |
2806 | int i; |
2807 | int do_wakeup = 0; |
2808 | sector_t tree_index; |
2809 | void __rcu **pslot; |
2810 | uintptr_t refcount; |
2811 | |
2812 | if (!log || !test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags)) |
2813 | return; |
2814 | |
2815 | WARN_ON(test_bit(STRIPE_R5C_CACHING, &sh->state)); |
2816 | clear_bit(nr: R5_InJournal, addr: &sh->dev[sh->pd_idx].flags); |
2817 | |
2818 | if (log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_THROUGH) |
2819 | return; |
2820 | |
2821 | for (i = sh->disks; i--; ) { |
2822 | clear_bit(nr: R5_InJournal, addr: &sh->dev[i].flags); |
2823 | if (test_and_clear_bit(nr: R5_Overlap, addr: &sh->dev[i].flags)) |
2824 | do_wakeup = 1; |
2825 | } |
2826 | |
2827 | /* |
2828 | * analyse_stripe() runs before r5c_finish_stripe_write_out(), |
2829 | * We updated R5_InJournal, so we also update s->injournal. |
2830 | */ |
2831 | s->injournal = 0; |
2832 | |
2833 | if (test_and_clear_bit(nr: STRIPE_FULL_WRITE, addr: &sh->state)) |
2834 | if (atomic_dec_and_test(v: &conf->pending_full_writes)) |
2835 | md_wakeup_thread(thread: conf->mddev->thread); |
2836 | |
2837 | if (do_wakeup) |
2838 | wake_up(&conf->wait_for_overlap); |
2839 | |
2840 | spin_lock_irq(lock: &log->stripe_in_journal_lock); |
2841 | list_del_init(entry: &sh->r5c); |
2842 | spin_unlock_irq(lock: &log->stripe_in_journal_lock); |
2843 | sh->log_start = MaxSector; |
2844 | |
2845 | atomic_dec(v: &log->stripe_in_journal_count); |
2846 | r5c_update_log_state(log); |
2847 | |
2848 | /* stop counting this stripe in big_stripe_tree */ |
2849 | if (test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) || |
2850 | test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state)) { |
2851 | tree_index = r5c_tree_index(conf, sect: sh->sector); |
2852 | spin_lock(lock: &log->tree_lock); |
2853 | pslot = radix_tree_lookup_slot(&log->big_stripe_tree, |
2854 | index: tree_index); |
2855 | BUG_ON(pslot == NULL); |
2856 | refcount = (uintptr_t)radix_tree_deref_slot_protected( |
2857 | slot: pslot, treelock: &log->tree_lock) >> |
2858 | R5C_RADIX_COUNT_SHIFT; |
2859 | if (refcount == 1) |
2860 | radix_tree_delete(&log->big_stripe_tree, tree_index); |
2861 | else |
2862 | radix_tree_replace_slot( |
2863 | &log->big_stripe_tree, slot: pslot, |
2864 | entry: (void *)((refcount - 1) << R5C_RADIX_COUNT_SHIFT)); |
2865 | spin_unlock(lock: &log->tree_lock); |
2866 | } |
2867 | |
2868 | if (test_and_clear_bit(nr: STRIPE_R5C_PARTIAL_STRIPE, addr: &sh->state)) { |
2869 | BUG_ON(atomic_read(&conf->r5c_cached_partial_stripes) == 0); |
2870 | atomic_dec(v: &conf->r5c_flushing_partial_stripes); |
2871 | atomic_dec(v: &conf->r5c_cached_partial_stripes); |
2872 | } |
2873 | |
2874 | if (test_and_clear_bit(nr: STRIPE_R5C_FULL_STRIPE, addr: &sh->state)) { |
2875 | BUG_ON(atomic_read(&conf->r5c_cached_full_stripes) == 0); |
2876 | atomic_dec(v: &conf->r5c_flushing_full_stripes); |
2877 | atomic_dec(v: &conf->r5c_cached_full_stripes); |
2878 | } |
2879 | |
2880 | r5l_append_flush_payload(log, sect: sh->sector); |
2881 | /* stripe is flused to raid disks, we can do resync now */ |
2882 | if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state)) |
2883 | set_bit(nr: STRIPE_HANDLE, addr: &sh->state); |
2884 | } |
2885 | |
2886 | int r5c_cache_data(struct r5l_log *log, struct stripe_head *sh) |
2887 | { |
2888 | struct r5conf *conf = sh->raid_conf; |
2889 | int pages = 0; |
2890 | int reserve; |
2891 | int i; |
2892 | int ret = 0; |
2893 | |
2894 | BUG_ON(!log); |
2895 | |
2896 | for (i = 0; i < sh->disks; i++) { |
2897 | void *addr; |
2898 | |
2899 | if (!test_bit(R5_Wantwrite, &sh->dev[i].flags)) |
2900 | continue; |
2901 | addr = kmap_atomic(page: sh->dev[i].page); |
2902 | sh->dev[i].log_checksum = crc32c_le(crc: log->uuid_checksum, |
2903 | address: addr, PAGE_SIZE); |
2904 | kunmap_atomic(addr); |
2905 | pages++; |
2906 | } |
2907 | WARN_ON(pages == 0); |
2908 | |
2909 | /* |
2910 | * The stripe must enter state machine again to call endio, so |
2911 | * don't delay. |
2912 | */ |
2913 | clear_bit(nr: STRIPE_DELAYED, addr: &sh->state); |
2914 | atomic_inc(v: &sh->count); |
2915 | |
2916 | mutex_lock(&log->io_mutex); |
2917 | /* meta + data */ |
2918 | reserve = (1 + pages) << (PAGE_SHIFT - 9); |
2919 | |
2920 | if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) && |
2921 | sh->log_start == MaxSector) |
2922 | r5l_add_no_space_stripe(log, sh); |
2923 | else if (!r5l_has_free_space(log, size: reserve)) { |
2924 | if (sh->log_start == log->last_checkpoint) |
2925 | BUG(); |
2926 | else |
2927 | r5l_add_no_space_stripe(log, sh); |
2928 | } else { |
2929 | ret = r5l_log_stripe(log, sh, data_pages: pages, parity_pages: 0); |
2930 | if (ret) { |
2931 | spin_lock_irq(lock: &log->io_list_lock); |
2932 | list_add_tail(new: &sh->log_list, head: &log->no_mem_stripes); |
2933 | spin_unlock_irq(lock: &log->io_list_lock); |
2934 | } |
2935 | } |
2936 | |
2937 | mutex_unlock(lock: &log->io_mutex); |
2938 | return 0; |
2939 | } |
2940 | |
2941 | /* check whether this big stripe is in write back cache. */ |
2942 | bool r5c_big_stripe_cached(struct r5conf *conf, sector_t sect) |
2943 | { |
2944 | struct r5l_log *log = READ_ONCE(conf->log); |
2945 | sector_t tree_index; |
2946 | void *slot; |
2947 | |
2948 | if (!log) |
2949 | return false; |
2950 | |
2951 | WARN_ON_ONCE(!rcu_read_lock_held()); |
2952 | tree_index = r5c_tree_index(conf, sect); |
2953 | slot = radix_tree_lookup(&log->big_stripe_tree, tree_index); |
2954 | return slot != NULL; |
2955 | } |
2956 | |
2957 | static int r5l_load_log(struct r5l_log *log) |
2958 | { |
2959 | struct md_rdev *rdev = log->rdev; |
2960 | struct page *page; |
2961 | struct r5l_meta_block *mb; |
2962 | sector_t cp = log->rdev->journal_tail; |
2963 | u32 stored_crc, expected_crc; |
2964 | bool create_super = false; |
2965 | int ret = 0; |
2966 | |
2967 | /* Make sure it's valid */ |
2968 | if (cp >= rdev->sectors || round_down(cp, BLOCK_SECTORS) != cp) |
2969 | cp = 0; |
2970 | page = alloc_page(GFP_KERNEL); |
2971 | if (!page) |
2972 | return -ENOMEM; |
2973 | |
2974 | if (!sync_page_io(rdev, sector: cp, PAGE_SIZE, page, opf: REQ_OP_READ, metadata_op: false)) { |
2975 | ret = -EIO; |
2976 | goto ioerr; |
2977 | } |
2978 | mb = page_address(page); |
2979 | |
2980 | if (le32_to_cpu(mb->magic) != R5LOG_MAGIC || |
2981 | mb->version != R5LOG_VERSION) { |
2982 | create_super = true; |
2983 | goto create; |
2984 | } |
2985 | stored_crc = le32_to_cpu(mb->checksum); |
2986 | mb->checksum = 0; |
2987 | expected_crc = crc32c_le(crc: log->uuid_checksum, address: mb, PAGE_SIZE); |
2988 | if (stored_crc != expected_crc) { |
2989 | create_super = true; |
2990 | goto create; |
2991 | } |
2992 | if (le64_to_cpu(mb->position) != cp) { |
2993 | create_super = true; |
2994 | goto create; |
2995 | } |
2996 | create: |
2997 | if (create_super) { |
2998 | log->last_cp_seq = get_random_u32(); |
2999 | cp = 0; |
3000 | r5l_log_write_empty_meta_block(log, pos: cp, seq: log->last_cp_seq); |
3001 | /* |
3002 | * Make sure super points to correct address. Log might have |
3003 | * data very soon. If super hasn't correct log tail address, |
3004 | * recovery can't find the log |
3005 | */ |
3006 | r5l_write_super(log, cp); |
3007 | } else |
3008 | log->last_cp_seq = le64_to_cpu(mb->seq); |
3009 | |
3010 | log->device_size = round_down(rdev->sectors, BLOCK_SECTORS); |
3011 | log->max_free_space = log->device_size >> RECLAIM_MAX_FREE_SPACE_SHIFT; |
3012 | if (log->max_free_space > RECLAIM_MAX_FREE_SPACE) |
3013 | log->max_free_space = RECLAIM_MAX_FREE_SPACE; |
3014 | log->last_checkpoint = cp; |
3015 | |
3016 | __free_page(page); |
3017 | |
3018 | if (create_super) { |
3019 | log->log_start = r5l_ring_add(log, start: cp, BLOCK_SECTORS); |
3020 | log->seq = log->last_cp_seq + 1; |
3021 | log->next_checkpoint = cp; |
3022 | } else |
3023 | ret = r5l_recovery_log(log); |
3024 | |
3025 | r5c_update_log_state(log); |
3026 | return ret; |
3027 | ioerr: |
3028 | __free_page(page); |
3029 | return ret; |
3030 | } |
3031 | |
3032 | int r5l_start(struct r5l_log *log) |
3033 | { |
3034 | int ret; |
3035 | |
3036 | if (!log) |
3037 | return 0; |
3038 | |
3039 | ret = r5l_load_log(log); |
3040 | if (ret) { |
3041 | struct mddev *mddev = log->rdev->mddev; |
3042 | struct r5conf *conf = mddev->private; |
3043 | |
3044 | r5l_exit_log(conf); |
3045 | } |
3046 | return ret; |
3047 | } |
3048 | |
3049 | void r5c_update_on_rdev_error(struct mddev *mddev, struct md_rdev *rdev) |
3050 | { |
3051 | struct r5conf *conf = mddev->private; |
3052 | struct r5l_log *log = READ_ONCE(conf->log); |
3053 | |
3054 | if (!log) |
3055 | return; |
3056 | |
3057 | if ((raid5_calc_degraded(conf) > 0 || |
3058 | test_bit(Journal, &rdev->flags)) && |
3059 | log->r5c_journal_mode == R5C_JOURNAL_MODE_WRITE_BACK) |
3060 | schedule_work(work: &log->disable_writeback_work); |
3061 | } |
3062 | |
3063 | int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev) |
3064 | { |
3065 | struct r5l_log *log; |
3066 | struct md_thread *thread; |
3067 | int ret; |
3068 | |
3069 | pr_debug("md/raid:%s: using device %pg as journal\n" , |
3070 | mdname(conf->mddev), rdev->bdev); |
3071 | |
3072 | if (PAGE_SIZE != 4096) |
3073 | return -EINVAL; |
3074 | |
3075 | /* |
3076 | * The PAGE_SIZE must be big enough to hold 1 r5l_meta_block and |
3077 | * raid_disks r5l_payload_data_parity. |
3078 | * |
3079 | * Write journal and cache does not work for very big array |
3080 | * (raid_disks > 203) |
3081 | */ |
3082 | if (sizeof(struct r5l_meta_block) + |
3083 | ((sizeof(struct r5l_payload_data_parity) + sizeof(__le32)) * |
3084 | conf->raid_disks) > PAGE_SIZE) { |
3085 | pr_err("md/raid:%s: write journal/cache doesn't work for array with %d disks\n" , |
3086 | mdname(conf->mddev), conf->raid_disks); |
3087 | return -EINVAL; |
3088 | } |
3089 | |
3090 | log = kzalloc(size: sizeof(*log), GFP_KERNEL); |
3091 | if (!log) |
3092 | return -ENOMEM; |
3093 | log->rdev = rdev; |
3094 | log->need_cache_flush = bdev_write_cache(bdev: rdev->bdev); |
3095 | log->uuid_checksum = crc32c_le(crc: ~0, address: rdev->mddev->uuid, |
3096 | length: sizeof(rdev->mddev->uuid)); |
3097 | |
3098 | mutex_init(&log->io_mutex); |
3099 | |
3100 | spin_lock_init(&log->io_list_lock); |
3101 | INIT_LIST_HEAD(list: &log->running_ios); |
3102 | INIT_LIST_HEAD(list: &log->io_end_ios); |
3103 | INIT_LIST_HEAD(list: &log->flushing_ios); |
3104 | INIT_LIST_HEAD(list: &log->finished_ios); |
3105 | |
3106 | log->io_kc = KMEM_CACHE(r5l_io_unit, 0); |
3107 | if (!log->io_kc) |
3108 | goto io_kc; |
3109 | |
3110 | ret = mempool_init_slab_pool(pool: &log->io_pool, R5L_POOL_SIZE, kc: log->io_kc); |
3111 | if (ret) |
3112 | goto io_pool; |
3113 | |
3114 | ret = bioset_init(&log->bs, R5L_POOL_SIZE, 0, flags: BIOSET_NEED_BVECS); |
3115 | if (ret) |
3116 | goto io_bs; |
3117 | |
3118 | ret = mempool_init_page_pool(pool: &log->meta_pool, R5L_POOL_SIZE, order: 0); |
3119 | if (ret) |
3120 | goto out_mempool; |
3121 | |
3122 | spin_lock_init(&log->tree_lock); |
3123 | INIT_RADIX_TREE(&log->big_stripe_tree, GFP_NOWAIT | __GFP_NOWARN); |
3124 | |
3125 | thread = md_register_thread(run: r5l_reclaim_thread, mddev: log->rdev->mddev, |
3126 | name: "reclaim" ); |
3127 | if (!thread) |
3128 | goto reclaim_thread; |
3129 | |
3130 | thread->timeout = R5C_RECLAIM_WAKEUP_INTERVAL; |
3131 | rcu_assign_pointer(log->reclaim_thread, thread); |
3132 | |
3133 | init_waitqueue_head(&log->iounit_wait); |
3134 | |
3135 | INIT_LIST_HEAD(list: &log->no_mem_stripes); |
3136 | |
3137 | INIT_LIST_HEAD(list: &log->no_space_stripes); |
3138 | spin_lock_init(&log->no_space_stripes_lock); |
3139 | |
3140 | INIT_WORK(&log->deferred_io_work, r5l_submit_io_async); |
3141 | INIT_WORK(&log->disable_writeback_work, r5c_disable_writeback_async); |
3142 | |
3143 | log->r5c_journal_mode = R5C_JOURNAL_MODE_WRITE_THROUGH; |
3144 | INIT_LIST_HEAD(list: &log->stripe_in_journal_list); |
3145 | spin_lock_init(&log->stripe_in_journal_lock); |
3146 | atomic_set(v: &log->stripe_in_journal_count, i: 0); |
3147 | |
3148 | WRITE_ONCE(conf->log, log); |
3149 | |
3150 | set_bit(nr: MD_HAS_JOURNAL, addr: &conf->mddev->flags); |
3151 | return 0; |
3152 | |
3153 | reclaim_thread: |
3154 | mempool_exit(pool: &log->meta_pool); |
3155 | out_mempool: |
3156 | bioset_exit(&log->bs); |
3157 | io_bs: |
3158 | mempool_exit(pool: &log->io_pool); |
3159 | io_pool: |
3160 | kmem_cache_destroy(s: log->io_kc); |
3161 | io_kc: |
3162 | kfree(objp: log); |
3163 | return -EINVAL; |
3164 | } |
3165 | |
3166 | void r5l_exit_log(struct r5conf *conf) |
3167 | { |
3168 | struct r5l_log *log = conf->log; |
3169 | |
3170 | md_unregister_thread(mddev: conf->mddev, threadp: &log->reclaim_thread); |
3171 | |
3172 | /* |
3173 | * 'reconfig_mutex' is held by caller, set 'confg->log' to NULL to |
3174 | * ensure disable_writeback_work wakes up and exits. |
3175 | */ |
3176 | WRITE_ONCE(conf->log, NULL); |
3177 | wake_up(&conf->mddev->sb_wait); |
3178 | flush_work(work: &log->disable_writeback_work); |
3179 | |
3180 | mempool_exit(pool: &log->meta_pool); |
3181 | bioset_exit(&log->bs); |
3182 | mempool_exit(pool: &log->io_pool); |
3183 | kmem_cache_destroy(s: log->io_kc); |
3184 | kfree(objp: log); |
3185 | } |
3186 | |