1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
4 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
5 */
6
7 #include <linux/sched.h>
8 #include <linux/slab.h>
9 #include <linux/spinlock.h>
10 #include <linux/completion.h>
11 #include <linux/buffer_head.h>
12 #include <linux/gfs2_ondisk.h>
13 #include <linux/crc32.h>
14 #include <linux/crc32c.h>
15 #include <linux/delay.h>
16 #include <linux/kthread.h>
17 #include <linux/freezer.h>
18 #include <linux/bio.h>
19 #include <linux/blkdev.h>
20 #include <linux/writeback.h>
21 #include <linux/list_sort.h>
22
23 #include "gfs2.h"
24 #include "incore.h"
25 #include "bmap.h"
26 #include "glock.h"
27 #include "log.h"
28 #include "lops.h"
29 #include "meta_io.h"
30 #include "util.h"
31 #include "dir.h"
32 #include "trace_gfs2.h"
33 #include "trans.h"
34
35 static void gfs2_log_shutdown(struct gfs2_sbd *sdp);
36
37 /**
38 * gfs2_struct2blk - compute stuff
39 * @sdp: the filesystem
40 * @nstruct: the number of structures
41 *
42 * Compute the number of log descriptor blocks needed to hold a certain number
43 * of structures of a certain size.
44 *
45 * Returns: the number of blocks needed (minimum is always 1)
46 */
47
gfs2_struct2blk(struct gfs2_sbd * sdp,unsigned int nstruct)48 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct)
49 {
50 unsigned int blks;
51 unsigned int first, second;
52
53 /* The initial struct gfs2_log_descriptor block */
54 blks = 1;
55 first = sdp->sd_ldptrs;
56
57 if (nstruct > first) {
58 /* Subsequent struct gfs2_meta_header blocks */
59 second = sdp->sd_inptrs;
60 blks += DIV_ROUND_UP(nstruct - first, second);
61 }
62
63 return blks;
64 }
65
66 /**
67 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
68 * @bd: The gfs2_bufdata to remove
69 *
70 * The ail lock _must_ be held when calling this function
71 *
72 */
73
gfs2_remove_from_ail(struct gfs2_bufdata * bd)74 void gfs2_remove_from_ail(struct gfs2_bufdata *bd)
75 {
76 bd->bd_tr = NULL;
77 list_del_init(&bd->bd_ail_st_list);
78 list_del_init(&bd->bd_ail_gl_list);
79 atomic_dec(&bd->bd_gl->gl_ail_count);
80 brelse(bd->bd_bh);
81 }
82
__gfs2_writepage(struct folio * folio,struct writeback_control * wbc,void * data)83 static int __gfs2_writepage(struct folio *folio, struct writeback_control *wbc,
84 void *data)
85 {
86 struct address_space *mapping = data;
87 int ret = mapping->a_ops->writepage(&folio->page, wbc);
88 mapping_set_error(mapping, ret);
89 return ret;
90 }
91
92 /**
93 * gfs2_ail1_start_one - Start I/O on a transaction
94 * @sdp: The superblock
95 * @wbc: The writeback control structure
96 * @tr: The transaction to start I/O on
97 * @plug: The block plug currently active
98 */
99
gfs2_ail1_start_one(struct gfs2_sbd * sdp,struct writeback_control * wbc,struct gfs2_trans * tr,struct blk_plug * plug)100 static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
101 struct writeback_control *wbc,
102 struct gfs2_trans *tr, struct blk_plug *plug)
103 __releases(&sdp->sd_ail_lock)
104 __acquires(&sdp->sd_ail_lock)
105 {
106 struct gfs2_glock *gl = NULL;
107 struct address_space *mapping;
108 struct gfs2_bufdata *bd, *s;
109 struct buffer_head *bh;
110 int ret = 0;
111
112 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
113 bh = bd->bd_bh;
114
115 gfs2_assert(sdp, bd->bd_tr == tr);
116
117 if (!buffer_busy(bh)) {
118 if (buffer_uptodate(bh)) {
119 list_move(&bd->bd_ail_st_list,
120 &tr->tr_ail2_list);
121 continue;
122 }
123 if (!cmpxchg(&sdp->sd_log_error, 0, -EIO)) {
124 gfs2_io_error_bh(sdp, bh);
125 gfs2_withdraw_delayed(sdp);
126 }
127 }
128
129 if (gfs2_withdrawn(sdp)) {
130 gfs2_remove_from_ail(bd);
131 continue;
132 }
133 if (!buffer_dirty(bh))
134 continue;
135 if (gl == bd->bd_gl)
136 continue;
137 gl = bd->bd_gl;
138 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
139 mapping = bh->b_folio->mapping;
140 if (!mapping)
141 continue;
142 spin_unlock(&sdp->sd_ail_lock);
143 ret = write_cache_pages(mapping, wbc, __gfs2_writepage, mapping);
144 if (need_resched()) {
145 blk_finish_plug(plug);
146 cond_resched();
147 blk_start_plug(plug);
148 }
149 spin_lock(&sdp->sd_ail_lock);
150 if (ret == -ENODATA) /* if a jdata write into a new hole */
151 ret = 0; /* ignore it */
152 if (ret || wbc->nr_to_write <= 0)
153 break;
154 return -EBUSY;
155 }
156
157 return ret;
158 }
159
dump_ail_list(struct gfs2_sbd * sdp)160 static void dump_ail_list(struct gfs2_sbd *sdp)
161 {
162 struct gfs2_trans *tr;
163 struct gfs2_bufdata *bd;
164 struct buffer_head *bh;
165
166 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
167 list_for_each_entry_reverse(bd, &tr->tr_ail1_list,
168 bd_ail_st_list) {
169 bh = bd->bd_bh;
170 fs_err(sdp, "bd %p: blk:0x%llx bh=%p ", bd,
171 (unsigned long long)bd->bd_blkno, bh);
172 if (!bh) {
173 fs_err(sdp, "\n");
174 continue;
175 }
176 fs_err(sdp, "0x%llx up2:%d dirt:%d lkd:%d req:%d "
177 "map:%d new:%d ar:%d aw:%d delay:%d "
178 "io err:%d unwritten:%d dfr:%d pin:%d esc:%d\n",
179 (unsigned long long)bh->b_blocknr,
180 buffer_uptodate(bh), buffer_dirty(bh),
181 buffer_locked(bh), buffer_req(bh),
182 buffer_mapped(bh), buffer_new(bh),
183 buffer_async_read(bh), buffer_async_write(bh),
184 buffer_delay(bh), buffer_write_io_error(bh),
185 buffer_unwritten(bh),
186 buffer_defer_completion(bh),
187 buffer_pinned(bh), buffer_escaped(bh));
188 }
189 }
190 }
191
192 /**
193 * gfs2_ail1_flush - start writeback of some ail1 entries
194 * @sdp: The super block
195 * @wbc: The writeback control structure
196 *
197 * Writes back some ail1 entries, according to the limits in the
198 * writeback control structure
199 */
200
gfs2_ail1_flush(struct gfs2_sbd * sdp,struct writeback_control * wbc)201 void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
202 {
203 struct list_head *head = &sdp->sd_ail1_list;
204 struct gfs2_trans *tr;
205 struct blk_plug plug;
206 int ret;
207 unsigned long flush_start = jiffies;
208
209 trace_gfs2_ail_flush(sdp, wbc, 1);
210 blk_start_plug(&plug);
211 spin_lock(&sdp->sd_ail_lock);
212 restart:
213 ret = 0;
214 if (time_after(jiffies, flush_start + (HZ * 600))) {
215 fs_err(sdp, "Error: In %s for ten minutes! t=%d\n",
216 __func__, current->journal_info ? 1 : 0);
217 dump_ail_list(sdp);
218 goto out;
219 }
220 list_for_each_entry_reverse(tr, head, tr_list) {
221 if (wbc->nr_to_write <= 0)
222 break;
223 ret = gfs2_ail1_start_one(sdp, wbc, tr, &plug);
224 if (ret) {
225 if (ret == -EBUSY)
226 goto restart;
227 break;
228 }
229 }
230 out:
231 spin_unlock(&sdp->sd_ail_lock);
232 blk_finish_plug(&plug);
233 if (ret) {
234 gfs2_lm(sdp, "gfs2_ail1_start_one returned: %d\n", ret);
235 gfs2_withdraw(sdp);
236 }
237 trace_gfs2_ail_flush(sdp, wbc, 0);
238 }
239
240 /**
241 * gfs2_ail1_start - start writeback of all ail1 entries
242 * @sdp: The superblock
243 */
244
gfs2_ail1_start(struct gfs2_sbd * sdp)245 static void gfs2_ail1_start(struct gfs2_sbd *sdp)
246 {
247 struct writeback_control wbc = {
248 .sync_mode = WB_SYNC_NONE,
249 .nr_to_write = LONG_MAX,
250 .range_start = 0,
251 .range_end = LLONG_MAX,
252 };
253
254 return gfs2_ail1_flush(sdp, &wbc);
255 }
256
gfs2_log_update_flush_tail(struct gfs2_sbd * sdp)257 static void gfs2_log_update_flush_tail(struct gfs2_sbd *sdp)
258 {
259 unsigned int new_flush_tail = sdp->sd_log_head;
260 struct gfs2_trans *tr;
261
262 if (!list_empty(&sdp->sd_ail1_list)) {
263 tr = list_last_entry(&sdp->sd_ail1_list,
264 struct gfs2_trans, tr_list);
265 new_flush_tail = tr->tr_first;
266 }
267 sdp->sd_log_flush_tail = new_flush_tail;
268 }
269
gfs2_log_update_head(struct gfs2_sbd * sdp)270 static void gfs2_log_update_head(struct gfs2_sbd *sdp)
271 {
272 unsigned int new_head = sdp->sd_log_flush_head;
273
274 if (sdp->sd_log_flush_tail == sdp->sd_log_head)
275 sdp->sd_log_flush_tail = new_head;
276 sdp->sd_log_head = new_head;
277 }
278
279 /*
280 * gfs2_ail_empty_tr - empty one of the ail lists of a transaction
281 */
282
gfs2_ail_empty_tr(struct gfs2_sbd * sdp,struct gfs2_trans * tr,struct list_head * head)283 static void gfs2_ail_empty_tr(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
284 struct list_head *head)
285 {
286 struct gfs2_bufdata *bd;
287
288 while (!list_empty(head)) {
289 bd = list_first_entry(head, struct gfs2_bufdata,
290 bd_ail_st_list);
291 gfs2_assert(sdp, bd->bd_tr == tr);
292 gfs2_remove_from_ail(bd);
293 }
294 }
295
296 /**
297 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
298 * @sdp: the filesystem
299 * @tr: the transaction
300 * @max_revokes: If nonzero, issue revokes for the bd items for written buffers
301 *
302 * returns: the transaction's count of remaining active items
303 */
304
gfs2_ail1_empty_one(struct gfs2_sbd * sdp,struct gfs2_trans * tr,int * max_revokes)305 static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
306 int *max_revokes)
307 {
308 struct gfs2_bufdata *bd, *s;
309 struct buffer_head *bh;
310 int active_count = 0;
311
312 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
313 bd_ail_st_list) {
314 bh = bd->bd_bh;
315 gfs2_assert(sdp, bd->bd_tr == tr);
316 /*
317 * If another process flagged an io error, e.g. writing to the
318 * journal, error all other bhs and move them off the ail1 to
319 * prevent a tight loop when unmount tries to flush ail1,
320 * regardless of whether they're still busy. If no outside
321 * errors were found and the buffer is busy, move to the next.
322 * If the ail buffer is not busy and caught an error, flag it
323 * for others.
324 */
325 if (!sdp->sd_log_error && buffer_busy(bh)) {
326 active_count++;
327 continue;
328 }
329 if (!buffer_uptodate(bh) &&
330 !cmpxchg(&sdp->sd_log_error, 0, -EIO)) {
331 gfs2_io_error_bh(sdp, bh);
332 gfs2_withdraw_delayed(sdp);
333 }
334 /*
335 * If we have space for revokes and the bd is no longer on any
336 * buf list, we can just add a revoke for it immediately and
337 * avoid having to put it on the ail2 list, where it would need
338 * to be revoked later.
339 */
340 if (*max_revokes && list_empty(&bd->bd_list)) {
341 gfs2_add_revoke(sdp, bd);
342 (*max_revokes)--;
343 continue;
344 }
345 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
346 }
347 return active_count;
348 }
349
350 /**
351 * gfs2_ail1_empty - Try to empty the ail1 lists
352 * @sdp: The superblock
353 * @max_revokes: If non-zero, add revokes where appropriate
354 *
355 * Tries to empty the ail1 lists, starting with the oldest first
356 */
357
gfs2_ail1_empty(struct gfs2_sbd * sdp,int max_revokes)358 static int gfs2_ail1_empty(struct gfs2_sbd *sdp, int max_revokes)
359 {
360 struct gfs2_trans *tr, *s;
361 int oldest_tr = 1;
362 int ret;
363
364 spin_lock(&sdp->sd_ail_lock);
365 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
366 if (!gfs2_ail1_empty_one(sdp, tr, &max_revokes) && oldest_tr)
367 list_move(&tr->tr_list, &sdp->sd_ail2_list);
368 else
369 oldest_tr = 0;
370 }
371 gfs2_log_update_flush_tail(sdp);
372 ret = list_empty(&sdp->sd_ail1_list);
373 spin_unlock(&sdp->sd_ail_lock);
374
375 if (test_bit(SDF_WITHDRAWING, &sdp->sd_flags)) {
376 gfs2_lm(sdp, "fatal: I/O error(s)\n");
377 gfs2_withdraw(sdp);
378 }
379
380 return ret;
381 }
382
gfs2_ail1_wait(struct gfs2_sbd * sdp)383 static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
384 {
385 struct gfs2_trans *tr;
386 struct gfs2_bufdata *bd;
387 struct buffer_head *bh;
388
389 spin_lock(&sdp->sd_ail_lock);
390 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
391 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
392 bh = bd->bd_bh;
393 if (!buffer_locked(bh))
394 continue;
395 get_bh(bh);
396 spin_unlock(&sdp->sd_ail_lock);
397 wait_on_buffer(bh);
398 brelse(bh);
399 return;
400 }
401 }
402 spin_unlock(&sdp->sd_ail_lock);
403 }
404
__ail2_empty(struct gfs2_sbd * sdp,struct gfs2_trans * tr)405 static void __ail2_empty(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
406 {
407 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
408 list_del(&tr->tr_list);
409 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
410 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
411 gfs2_trans_free(sdp, tr);
412 }
413
ail2_empty(struct gfs2_sbd * sdp,unsigned int new_tail)414 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
415 {
416 struct list_head *ail2_list = &sdp->sd_ail2_list;
417 unsigned int old_tail = sdp->sd_log_tail;
418 struct gfs2_trans *tr, *safe;
419
420 spin_lock(&sdp->sd_ail_lock);
421 if (old_tail <= new_tail) {
422 list_for_each_entry_safe(tr, safe, ail2_list, tr_list) {
423 if (old_tail <= tr->tr_first && tr->tr_first < new_tail)
424 __ail2_empty(sdp, tr);
425 }
426 } else {
427 list_for_each_entry_safe(tr, safe, ail2_list, tr_list) {
428 if (old_tail <= tr->tr_first || tr->tr_first < new_tail)
429 __ail2_empty(sdp, tr);
430 }
431 }
432 spin_unlock(&sdp->sd_ail_lock);
433 }
434
435 /**
436 * gfs2_log_is_empty - Check if the log is empty
437 * @sdp: The GFS2 superblock
438 */
439
gfs2_log_is_empty(struct gfs2_sbd * sdp)440 bool gfs2_log_is_empty(struct gfs2_sbd *sdp) {
441 return atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks;
442 }
443
__gfs2_log_try_reserve_revokes(struct gfs2_sbd * sdp,unsigned int revokes)444 static bool __gfs2_log_try_reserve_revokes(struct gfs2_sbd *sdp, unsigned int revokes)
445 {
446 unsigned int available;
447
448 available = atomic_read(&sdp->sd_log_revokes_available);
449 while (available >= revokes) {
450 if (atomic_try_cmpxchg(&sdp->sd_log_revokes_available,
451 &available, available - revokes))
452 return true;
453 }
454 return false;
455 }
456
457 /**
458 * gfs2_log_release_revokes - Release a given number of revokes
459 * @sdp: The GFS2 superblock
460 * @revokes: The number of revokes to release
461 *
462 * sdp->sd_log_flush_lock must be held.
463 */
gfs2_log_release_revokes(struct gfs2_sbd * sdp,unsigned int revokes)464 void gfs2_log_release_revokes(struct gfs2_sbd *sdp, unsigned int revokes)
465 {
466 if (revokes)
467 atomic_add(revokes, &sdp->sd_log_revokes_available);
468 }
469
470 /**
471 * gfs2_log_release - Release a given number of log blocks
472 * @sdp: The GFS2 superblock
473 * @blks: The number of blocks
474 *
475 */
476
gfs2_log_release(struct gfs2_sbd * sdp,unsigned int blks)477 void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks)
478 {
479 atomic_add(blks, &sdp->sd_log_blks_free);
480 trace_gfs2_log_blocks(sdp, blks);
481 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
482 sdp->sd_jdesc->jd_blocks);
483 if (atomic_read(&sdp->sd_log_blks_needed))
484 wake_up(&sdp->sd_log_waitq);
485 }
486
487 /**
488 * __gfs2_log_try_reserve - Try to make a log reservation
489 * @sdp: The GFS2 superblock
490 * @blks: The number of blocks to reserve
491 * @taboo_blks: The number of blocks to leave free
492 *
493 * Try to do the same as __gfs2_log_reserve(), but fail if no more log
494 * space is immediately available.
495 */
__gfs2_log_try_reserve(struct gfs2_sbd * sdp,unsigned int blks,unsigned int taboo_blks)496 static bool __gfs2_log_try_reserve(struct gfs2_sbd *sdp, unsigned int blks,
497 unsigned int taboo_blks)
498 {
499 unsigned wanted = blks + taboo_blks;
500 unsigned int free_blocks;
501
502 free_blocks = atomic_read(&sdp->sd_log_blks_free);
503 while (free_blocks >= wanted) {
504 if (atomic_try_cmpxchg(&sdp->sd_log_blks_free, &free_blocks,
505 free_blocks - blks)) {
506 trace_gfs2_log_blocks(sdp, -blks);
507 return true;
508 }
509 }
510 return false;
511 }
512
513 /**
514 * __gfs2_log_reserve - Make a log reservation
515 * @sdp: The GFS2 superblock
516 * @blks: The number of blocks to reserve
517 * @taboo_blks: The number of blocks to leave free
518 *
519 * @taboo_blks is set to 0 for logd, and to GFS2_LOG_FLUSH_MIN_BLOCKS
520 * for all other processes. This ensures that when the log is almost full,
521 * logd will still be able to call gfs2_log_flush one more time without
522 * blocking, which will advance the tail and make some more log space
523 * available.
524 *
525 * We no longer flush the log here, instead we wake up logd to do that
526 * for us. To avoid the thundering herd and to ensure that we deal fairly
527 * with queued waiters, we use an exclusive wait. This means that when we
528 * get woken with enough journal space to get our reservation, we need to
529 * wake the next waiter on the list.
530 */
531
__gfs2_log_reserve(struct gfs2_sbd * sdp,unsigned int blks,unsigned int taboo_blks)532 static void __gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks,
533 unsigned int taboo_blks)
534 {
535 unsigned wanted = blks + taboo_blks;
536 unsigned int free_blocks;
537
538 atomic_add(blks, &sdp->sd_log_blks_needed);
539 for (;;) {
540 if (current != sdp->sd_logd_process)
541 wake_up(&sdp->sd_logd_waitq);
542 io_wait_event(sdp->sd_log_waitq,
543 (free_blocks = atomic_read(&sdp->sd_log_blks_free),
544 free_blocks >= wanted));
545 do {
546 if (atomic_try_cmpxchg(&sdp->sd_log_blks_free,
547 &free_blocks,
548 free_blocks - blks))
549 goto reserved;
550 } while (free_blocks >= wanted);
551 }
552
553 reserved:
554 trace_gfs2_log_blocks(sdp, -blks);
555 if (atomic_sub_return(blks, &sdp->sd_log_blks_needed))
556 wake_up(&sdp->sd_log_waitq);
557 }
558
559 /**
560 * gfs2_log_try_reserve - Try to make a log reservation
561 * @sdp: The GFS2 superblock
562 * @tr: The transaction
563 * @extra_revokes: The number of additional revokes reserved (output)
564 *
565 * This is similar to gfs2_log_reserve, but sdp->sd_log_flush_lock must be
566 * held for correct revoke accounting.
567 */
568
gfs2_log_try_reserve(struct gfs2_sbd * sdp,struct gfs2_trans * tr,unsigned int * extra_revokes)569 bool gfs2_log_try_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
570 unsigned int *extra_revokes)
571 {
572 unsigned int blks = tr->tr_reserved;
573 unsigned int revokes = tr->tr_revokes;
574 unsigned int revoke_blks = 0;
575
576 *extra_revokes = 0;
577 if (revokes && !__gfs2_log_try_reserve_revokes(sdp, revokes)) {
578 revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs);
579 *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes;
580 blks += revoke_blks;
581 }
582 if (!blks)
583 return true;
584 if (__gfs2_log_try_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS))
585 return true;
586 if (!revoke_blks)
587 gfs2_log_release_revokes(sdp, revokes);
588 return false;
589 }
590
591 /**
592 * gfs2_log_reserve - Make a log reservation
593 * @sdp: The GFS2 superblock
594 * @tr: The transaction
595 * @extra_revokes: The number of additional revokes reserved (output)
596 *
597 * sdp->sd_log_flush_lock must not be held.
598 */
599
gfs2_log_reserve(struct gfs2_sbd * sdp,struct gfs2_trans * tr,unsigned int * extra_revokes)600 void gfs2_log_reserve(struct gfs2_sbd *sdp, struct gfs2_trans *tr,
601 unsigned int *extra_revokes)
602 {
603 unsigned int blks = tr->tr_reserved;
604 unsigned int revokes = tr->tr_revokes;
605 unsigned int revoke_blks;
606
607 *extra_revokes = 0;
608 if (revokes) {
609 revoke_blks = DIV_ROUND_UP(revokes, sdp->sd_inptrs);
610 *extra_revokes = revoke_blks * sdp->sd_inptrs - revokes;
611 blks += revoke_blks;
612 }
613 __gfs2_log_reserve(sdp, blks, GFS2_LOG_FLUSH_MIN_BLOCKS);
614 }
615
616 /**
617 * log_distance - Compute distance between two journal blocks
618 * @sdp: The GFS2 superblock
619 * @newer: The most recent journal block of the pair
620 * @older: The older journal block of the pair
621 *
622 * Compute the distance (in the journal direction) between two
623 * blocks in the journal
624 *
625 * Returns: the distance in blocks
626 */
627
log_distance(struct gfs2_sbd * sdp,unsigned int newer,unsigned int older)628 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
629 unsigned int older)
630 {
631 int dist;
632
633 dist = newer - older;
634 if (dist < 0)
635 dist += sdp->sd_jdesc->jd_blocks;
636
637 return dist;
638 }
639
640 /**
641 * calc_reserved - Calculate the number of blocks to keep reserved
642 * @sdp: The GFS2 superblock
643 *
644 * This is complex. We need to reserve room for all our currently used
645 * metadata blocks (e.g. normal file I/O rewriting file time stamps) and
646 * all our journaled data blocks for journaled files (e.g. files in the
647 * meta_fs like rindex, or files for which chattr +j was done.)
648 * If we don't reserve enough space, corruption will follow.
649 *
650 * We can have metadata blocks and jdata blocks in the same journal. Each
651 * type gets its own log descriptor, for which we need to reserve a block.
652 * In fact, each type has the potential for needing more than one log descriptor
653 * in cases where we have more blocks than will fit in a log descriptor.
654 * Metadata journal entries take up half the space of journaled buffer entries.
655 *
656 * Also, we need to reserve blocks for revoke journal entries and one for an
657 * overall header for the lot.
658 *
659 * Returns: the number of blocks reserved
660 */
calc_reserved(struct gfs2_sbd * sdp)661 static unsigned int calc_reserved(struct gfs2_sbd *sdp)
662 {
663 unsigned int reserved = GFS2_LOG_FLUSH_MIN_BLOCKS;
664 unsigned int blocks;
665 struct gfs2_trans *tr = sdp->sd_log_tr;
666
667 if (tr) {
668 blocks = tr->tr_num_buf_new - tr->tr_num_buf_rm;
669 reserved += blocks + DIV_ROUND_UP(blocks, buf_limit(sdp));
670 blocks = tr->tr_num_databuf_new - tr->tr_num_databuf_rm;
671 reserved += blocks + DIV_ROUND_UP(blocks, databuf_limit(sdp));
672 }
673 return reserved;
674 }
675
log_pull_tail(struct gfs2_sbd * sdp)676 static void log_pull_tail(struct gfs2_sbd *sdp)
677 {
678 unsigned int new_tail = sdp->sd_log_flush_tail;
679 unsigned int dist;
680
681 if (new_tail == sdp->sd_log_tail)
682 return;
683 dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
684 ail2_empty(sdp, new_tail);
685 gfs2_log_release(sdp, dist);
686 sdp->sd_log_tail = new_tail;
687 }
688
689
log_flush_wait(struct gfs2_sbd * sdp)690 void log_flush_wait(struct gfs2_sbd *sdp)
691 {
692 DEFINE_WAIT(wait);
693
694 if (atomic_read(&sdp->sd_log_in_flight)) {
695 do {
696 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
697 TASK_UNINTERRUPTIBLE);
698 if (atomic_read(&sdp->sd_log_in_flight))
699 io_schedule();
700 } while(atomic_read(&sdp->sd_log_in_flight));
701 finish_wait(&sdp->sd_log_flush_wait, &wait);
702 }
703 }
704
ip_cmp(void * priv,const struct list_head * a,const struct list_head * b)705 static int ip_cmp(void *priv, const struct list_head *a, const struct list_head *b)
706 {
707 struct gfs2_inode *ipa, *ipb;
708
709 ipa = list_entry(a, struct gfs2_inode, i_ordered);
710 ipb = list_entry(b, struct gfs2_inode, i_ordered);
711
712 if (ipa->i_no_addr < ipb->i_no_addr)
713 return -1;
714 if (ipa->i_no_addr > ipb->i_no_addr)
715 return 1;
716 return 0;
717 }
718
__ordered_del_inode(struct gfs2_inode * ip)719 static void __ordered_del_inode(struct gfs2_inode *ip)
720 {
721 if (!list_empty(&ip->i_ordered))
722 list_del_init(&ip->i_ordered);
723 }
724
gfs2_ordered_write(struct gfs2_sbd * sdp)725 static void gfs2_ordered_write(struct gfs2_sbd *sdp)
726 {
727 struct gfs2_inode *ip;
728 LIST_HEAD(written);
729
730 spin_lock(&sdp->sd_ordered_lock);
731 list_sort(NULL, &sdp->sd_log_ordered, &ip_cmp);
732 while (!list_empty(&sdp->sd_log_ordered)) {
733 ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered);
734 if (ip->i_inode.i_mapping->nrpages == 0) {
735 __ordered_del_inode(ip);
736 continue;
737 }
738 list_move(&ip->i_ordered, &written);
739 spin_unlock(&sdp->sd_ordered_lock);
740 filemap_fdatawrite(ip->i_inode.i_mapping);
741 spin_lock(&sdp->sd_ordered_lock);
742 }
743 list_splice(&written, &sdp->sd_log_ordered);
744 spin_unlock(&sdp->sd_ordered_lock);
745 }
746
gfs2_ordered_wait(struct gfs2_sbd * sdp)747 static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
748 {
749 struct gfs2_inode *ip;
750
751 spin_lock(&sdp->sd_ordered_lock);
752 while (!list_empty(&sdp->sd_log_ordered)) {
753 ip = list_first_entry(&sdp->sd_log_ordered, struct gfs2_inode, i_ordered);
754 __ordered_del_inode(ip);
755 if (ip->i_inode.i_mapping->nrpages == 0)
756 continue;
757 spin_unlock(&sdp->sd_ordered_lock);
758 filemap_fdatawait(ip->i_inode.i_mapping);
759 spin_lock(&sdp->sd_ordered_lock);
760 }
761 spin_unlock(&sdp->sd_ordered_lock);
762 }
763
gfs2_ordered_del_inode(struct gfs2_inode * ip)764 void gfs2_ordered_del_inode(struct gfs2_inode *ip)
765 {
766 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
767
768 spin_lock(&sdp->sd_ordered_lock);
769 __ordered_del_inode(ip);
770 spin_unlock(&sdp->sd_ordered_lock);
771 }
772
gfs2_add_revoke(struct gfs2_sbd * sdp,struct gfs2_bufdata * bd)773 void gfs2_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)
774 {
775 struct buffer_head *bh = bd->bd_bh;
776 struct gfs2_glock *gl = bd->bd_gl;
777
778 sdp->sd_log_num_revoke++;
779 if (atomic_inc_return(&gl->gl_revokes) == 1)
780 gfs2_glock_hold(gl);
781 bh->b_private = NULL;
782 bd->bd_blkno = bh->b_blocknr;
783 gfs2_remove_from_ail(bd); /* drops ref on bh */
784 bd->bd_bh = NULL;
785 set_bit(GLF_LFLUSH, &gl->gl_flags);
786 list_add(&bd->bd_list, &sdp->sd_log_revokes);
787 }
788
gfs2_glock_remove_revoke(struct gfs2_glock * gl)789 void gfs2_glock_remove_revoke(struct gfs2_glock *gl)
790 {
791 if (atomic_dec_return(&gl->gl_revokes) == 0) {
792 clear_bit(GLF_LFLUSH, &gl->gl_flags);
793 gfs2_glock_queue_put(gl);
794 }
795 }
796
797 /**
798 * gfs2_flush_revokes - Add as many revokes to the system transaction as we can
799 * @sdp: The GFS2 superblock
800 *
801 * Our usual strategy is to defer writing revokes as much as we can in the hope
802 * that we'll eventually overwrite the journal, which will make those revokes
803 * go away. This changes when we flush the log: at that point, there will
804 * likely be some left-over space in the last revoke block of that transaction.
805 * We can fill that space with additional revokes for blocks that have already
806 * been written back. This will basically come at no cost now, and will save
807 * us from having to keep track of those blocks on the AIL2 list later.
808 */
gfs2_flush_revokes(struct gfs2_sbd * sdp)809 void gfs2_flush_revokes(struct gfs2_sbd *sdp)
810 {
811 /* number of revokes we still have room for */
812 unsigned int max_revokes = atomic_read(&sdp->sd_log_revokes_available);
813
814 gfs2_log_lock(sdp);
815 gfs2_ail1_empty(sdp, max_revokes);
816 gfs2_log_unlock(sdp);
817 }
818
819 /**
820 * gfs2_write_log_header - Write a journal log header buffer at lblock
821 * @sdp: The GFS2 superblock
822 * @jd: journal descriptor of the journal to which we are writing
823 * @seq: sequence number
824 * @tail: tail of the log
825 * @lblock: value for lh_blkno (block number relative to start of journal)
826 * @flags: log header flags GFS2_LOG_HEAD_*
827 * @op_flags: flags to pass to the bio
828 *
829 * Returns: the initialized log buffer descriptor
830 */
831
gfs2_write_log_header(struct gfs2_sbd * sdp,struct gfs2_jdesc * jd,u64 seq,u32 tail,u32 lblock,u32 flags,blk_opf_t op_flags)832 void gfs2_write_log_header(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd,
833 u64 seq, u32 tail, u32 lblock, u32 flags,
834 blk_opf_t op_flags)
835 {
836 struct gfs2_log_header *lh;
837 u32 hash, crc;
838 struct page *page;
839 struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
840 struct timespec64 tv;
841 struct super_block *sb = sdp->sd_vfs;
842 u64 dblock;
843
844 if (gfs2_withdrawn(sdp))
845 return;
846
847 page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
848 lh = page_address(page);
849 clear_page(lh);
850
851 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
852 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
853 lh->lh_header.__pad0 = cpu_to_be64(0);
854 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
855 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
856 lh->lh_sequence = cpu_to_be64(seq);
857 lh->lh_flags = cpu_to_be32(flags);
858 lh->lh_tail = cpu_to_be32(tail);
859 lh->lh_blkno = cpu_to_be32(lblock);
860 hash = ~crc32(~0, lh, LH_V1_SIZE);
861 lh->lh_hash = cpu_to_be32(hash);
862
863 ktime_get_coarse_real_ts64(&tv);
864 lh->lh_nsec = cpu_to_be32(tv.tv_nsec);
865 lh->lh_sec = cpu_to_be64(tv.tv_sec);
866 if (!list_empty(&jd->extent_list))
867 dblock = gfs2_log_bmap(jd, lblock);
868 else {
869 unsigned int extlen;
870 int ret;
871
872 extlen = 1;
873 ret = gfs2_get_extent(jd->jd_inode, lblock, &dblock, &extlen);
874 if (gfs2_assert_withdraw(sdp, ret == 0))
875 return;
876 }
877 lh->lh_addr = cpu_to_be64(dblock);
878 lh->lh_jinode = cpu_to_be64(GFS2_I(jd->jd_inode)->i_no_addr);
879
880 /* We may only write local statfs, quota, etc., when writing to our
881 own journal. The values are left 0 when recovering a journal
882 different from our own. */
883 if (!(flags & GFS2_LOG_HEAD_RECOVERY)) {
884 lh->lh_statfs_addr =
885 cpu_to_be64(GFS2_I(sdp->sd_sc_inode)->i_no_addr);
886 lh->lh_quota_addr =
887 cpu_to_be64(GFS2_I(sdp->sd_qc_inode)->i_no_addr);
888
889 spin_lock(&sdp->sd_statfs_spin);
890 lh->lh_local_total = cpu_to_be64(l_sc->sc_total);
891 lh->lh_local_free = cpu_to_be64(l_sc->sc_free);
892 lh->lh_local_dinodes = cpu_to_be64(l_sc->sc_dinodes);
893 spin_unlock(&sdp->sd_statfs_spin);
894 }
895
896 BUILD_BUG_ON(offsetof(struct gfs2_log_header, lh_crc) != LH_V1_SIZE);
897
898 crc = crc32c(~0, (void *)lh + LH_V1_SIZE + 4,
899 sb->s_blocksize - LH_V1_SIZE - 4);
900 lh->lh_crc = cpu_to_be32(crc);
901
902 gfs2_log_write(sdp, jd, page, sb->s_blocksize, 0, dblock);
903 gfs2_log_submit_bio(&jd->jd_log_bio, REQ_OP_WRITE | op_flags);
904 }
905
906 /**
907 * log_write_header - Get and initialize a journal header buffer
908 * @sdp: The GFS2 superblock
909 * @flags: The log header flags, including log header origin
910 *
911 * Returns: the initialized log buffer descriptor
912 */
913
log_write_header(struct gfs2_sbd * sdp,u32 flags)914 static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
915 {
916 blk_opf_t op_flags = REQ_PREFLUSH | REQ_FUA | REQ_META | REQ_SYNC;
917
918 gfs2_assert_withdraw(sdp, !test_bit(SDF_FROZEN, &sdp->sd_flags));
919
920 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
921 gfs2_ordered_wait(sdp);
922 log_flush_wait(sdp);
923 op_flags = REQ_SYNC | REQ_META | REQ_PRIO;
924 }
925 sdp->sd_log_idle = (sdp->sd_log_flush_tail == sdp->sd_log_flush_head);
926 gfs2_write_log_header(sdp, sdp->sd_jdesc, sdp->sd_log_sequence++,
927 sdp->sd_log_flush_tail, sdp->sd_log_flush_head,
928 flags, op_flags);
929 gfs2_log_incr_head(sdp);
930 log_flush_wait(sdp);
931 log_pull_tail(sdp);
932 gfs2_log_update_head(sdp);
933 }
934
935 /**
936 * gfs2_ail_drain - drain the ail lists after a withdraw
937 * @sdp: Pointer to GFS2 superblock
938 */
gfs2_ail_drain(struct gfs2_sbd * sdp)939 void gfs2_ail_drain(struct gfs2_sbd *sdp)
940 {
941 struct gfs2_trans *tr;
942
943 spin_lock(&sdp->sd_ail_lock);
944 /*
945 * For transactions on the sd_ail1_list we need to drain both the
946 * ail1 and ail2 lists. That's because function gfs2_ail1_start_one
947 * (temporarily) moves items from its tr_ail1 list to tr_ail2 list
948 * before revokes are sent for that block. Items on the sd_ail2_list
949 * should have already gotten beyond that point, so no need.
950 */
951 while (!list_empty(&sdp->sd_ail1_list)) {
952 tr = list_first_entry(&sdp->sd_ail1_list, struct gfs2_trans,
953 tr_list);
954 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail1_list);
955 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
956 list_del(&tr->tr_list);
957 gfs2_trans_free(sdp, tr);
958 }
959 while (!list_empty(&sdp->sd_ail2_list)) {
960 tr = list_first_entry(&sdp->sd_ail2_list, struct gfs2_trans,
961 tr_list);
962 gfs2_ail_empty_tr(sdp, tr, &tr->tr_ail2_list);
963 list_del(&tr->tr_list);
964 gfs2_trans_free(sdp, tr);
965 }
966 gfs2_drain_revokes(sdp);
967 spin_unlock(&sdp->sd_ail_lock);
968 }
969
970 /**
971 * empty_ail1_list - try to start IO and empty the ail1 list
972 * @sdp: Pointer to GFS2 superblock
973 */
empty_ail1_list(struct gfs2_sbd * sdp)974 static void empty_ail1_list(struct gfs2_sbd *sdp)
975 {
976 unsigned long start = jiffies;
977
978 for (;;) {
979 if (time_after(jiffies, start + (HZ * 600))) {
980 fs_err(sdp, "Error: In %s for 10 minutes! t=%d\n",
981 __func__, current->journal_info ? 1 : 0);
982 dump_ail_list(sdp);
983 return;
984 }
985 gfs2_ail1_start(sdp);
986 gfs2_ail1_wait(sdp);
987 if (gfs2_ail1_empty(sdp, 0))
988 return;
989 }
990 }
991
992 /**
993 * trans_drain - drain the buf and databuf queue for a failed transaction
994 * @tr: the transaction to drain
995 *
996 * When this is called, we're taking an error exit for a log write that failed
997 * but since we bypassed the after_commit functions, we need to remove the
998 * items from the buf and databuf queue.
999 */
trans_drain(struct gfs2_trans * tr)1000 static void trans_drain(struct gfs2_trans *tr)
1001 {
1002 struct gfs2_bufdata *bd;
1003 struct list_head *head;
1004
1005 if (!tr)
1006 return;
1007
1008 head = &tr->tr_buf;
1009 while (!list_empty(head)) {
1010 bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
1011 list_del_init(&bd->bd_list);
1012 if (!list_empty(&bd->bd_ail_st_list))
1013 gfs2_remove_from_ail(bd);
1014 kmem_cache_free(gfs2_bufdata_cachep, bd);
1015 }
1016 head = &tr->tr_databuf;
1017 while (!list_empty(head)) {
1018 bd = list_first_entry(head, struct gfs2_bufdata, bd_list);
1019 list_del_init(&bd->bd_list);
1020 if (!list_empty(&bd->bd_ail_st_list))
1021 gfs2_remove_from_ail(bd);
1022 kmem_cache_free(gfs2_bufdata_cachep, bd);
1023 }
1024 }
1025
1026 /**
1027 * gfs2_log_flush - flush incore transaction(s)
1028 * @sdp: The filesystem
1029 * @gl: The glock structure to flush. If NULL, flush the whole incore log
1030 * @flags: The log header flags: GFS2_LOG_HEAD_FLUSH_* and debug flags
1031 *
1032 */
1033
gfs2_log_flush(struct gfs2_sbd * sdp,struct gfs2_glock * gl,u32 flags)1034 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl, u32 flags)
1035 {
1036 struct gfs2_trans *tr = NULL;
1037 unsigned int reserved_blocks = 0, used_blocks = 0;
1038 bool frozen = test_bit(SDF_FROZEN, &sdp->sd_flags);
1039 unsigned int first_log_head;
1040 unsigned int reserved_revokes = 0;
1041
1042 down_write(&sdp->sd_log_flush_lock);
1043 trace_gfs2_log_flush(sdp, 1, flags);
1044
1045 repeat:
1046 /*
1047 * Do this check while holding the log_flush_lock to prevent new
1048 * buffers from being added to the ail via gfs2_pin()
1049 */
1050 if (gfs2_withdrawn(sdp) || !test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
1051 goto out;
1052
1053 /* Log might have been flushed while we waited for the flush lock */
1054 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags))
1055 goto out;
1056
1057 first_log_head = sdp->sd_log_head;
1058 sdp->sd_log_flush_head = first_log_head;
1059
1060 tr = sdp->sd_log_tr;
1061 if (tr || sdp->sd_log_num_revoke) {
1062 if (reserved_blocks)
1063 gfs2_log_release(sdp, reserved_blocks);
1064 reserved_blocks = sdp->sd_log_blks_reserved;
1065 reserved_revokes = sdp->sd_log_num_revoke;
1066 if (tr) {
1067 sdp->sd_log_tr = NULL;
1068 tr->tr_first = first_log_head;
1069 if (unlikely(frozen)) {
1070 if (gfs2_assert_withdraw_delayed(sdp,
1071 !tr->tr_num_buf_new && !tr->tr_num_databuf_new))
1072 goto out_withdraw;
1073 }
1074 }
1075 } else if (!reserved_blocks) {
1076 unsigned int taboo_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS;
1077
1078 reserved_blocks = GFS2_LOG_FLUSH_MIN_BLOCKS;
1079 if (current == sdp->sd_logd_process)
1080 taboo_blocks = 0;
1081
1082 if (!__gfs2_log_try_reserve(sdp, reserved_blocks, taboo_blocks)) {
1083 up_write(&sdp->sd_log_flush_lock);
1084 __gfs2_log_reserve(sdp, reserved_blocks, taboo_blocks);
1085 down_write(&sdp->sd_log_flush_lock);
1086 goto repeat;
1087 }
1088 BUG_ON(sdp->sd_log_num_revoke);
1089 }
1090
1091 if (flags & GFS2_LOG_HEAD_FLUSH_SHUTDOWN)
1092 clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
1093
1094 if (unlikely(frozen))
1095 if (gfs2_assert_withdraw_delayed(sdp, !reserved_revokes))
1096 goto out_withdraw;
1097
1098 gfs2_ordered_write(sdp);
1099 if (gfs2_withdrawn(sdp))
1100 goto out_withdraw;
1101 lops_before_commit(sdp, tr);
1102 if (gfs2_withdrawn(sdp))
1103 goto out_withdraw;
1104 gfs2_log_submit_bio(&sdp->sd_jdesc->jd_log_bio, REQ_OP_WRITE);
1105 if (gfs2_withdrawn(sdp))
1106 goto out_withdraw;
1107
1108 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
1109 log_write_header(sdp, flags);
1110 } else if (sdp->sd_log_tail != sdp->sd_log_flush_tail && !sdp->sd_log_idle) {
1111 log_write_header(sdp, flags);
1112 }
1113 if (gfs2_withdrawn(sdp))
1114 goto out_withdraw;
1115 lops_after_commit(sdp, tr);
1116
1117 gfs2_log_lock(sdp);
1118 sdp->sd_log_blks_reserved = 0;
1119
1120 spin_lock(&sdp->sd_ail_lock);
1121 if (tr && !list_empty(&tr->tr_ail1_list)) {
1122 list_add(&tr->tr_list, &sdp->sd_ail1_list);
1123 tr = NULL;
1124 }
1125 spin_unlock(&sdp->sd_ail_lock);
1126 gfs2_log_unlock(sdp);
1127
1128 if (!(flags & GFS2_LOG_HEAD_FLUSH_NORMAL)) {
1129 if (!sdp->sd_log_idle) {
1130 empty_ail1_list(sdp);
1131 if (gfs2_withdrawn(sdp))
1132 goto out_withdraw;
1133 log_write_header(sdp, flags);
1134 }
1135 if (flags & (GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
1136 GFS2_LOG_HEAD_FLUSH_FREEZE))
1137 gfs2_log_shutdown(sdp);
1138 }
1139
1140 out_end:
1141 used_blocks = log_distance(sdp, sdp->sd_log_flush_head, first_log_head);
1142 reserved_revokes += atomic_read(&sdp->sd_log_revokes_available);
1143 atomic_set(&sdp->sd_log_revokes_available, sdp->sd_ldptrs);
1144 gfs2_assert_withdraw(sdp, reserved_revokes % sdp->sd_inptrs == sdp->sd_ldptrs);
1145 if (reserved_revokes > sdp->sd_ldptrs)
1146 reserved_blocks += (reserved_revokes - sdp->sd_ldptrs) / sdp->sd_inptrs;
1147 out:
1148 if (used_blocks != reserved_blocks) {
1149 gfs2_assert_withdraw_delayed(sdp, used_blocks < reserved_blocks);
1150 gfs2_log_release(sdp, reserved_blocks - used_blocks);
1151 }
1152 up_write(&sdp->sd_log_flush_lock);
1153 gfs2_trans_free(sdp, tr);
1154 if (gfs2_withdrawing(sdp))
1155 gfs2_withdraw(sdp);
1156 trace_gfs2_log_flush(sdp, 0, flags);
1157 return;
1158
1159 out_withdraw:
1160 trans_drain(tr);
1161 /**
1162 * If the tr_list is empty, we're withdrawing during a log
1163 * flush that targets a transaction, but the transaction was
1164 * never queued onto any of the ail lists. Here we add it to
1165 * ail1 just so that ail_drain() will find and free it.
1166 */
1167 spin_lock(&sdp->sd_ail_lock);
1168 if (tr && list_empty(&tr->tr_list))
1169 list_add(&tr->tr_list, &sdp->sd_ail1_list);
1170 spin_unlock(&sdp->sd_ail_lock);
1171 tr = NULL;
1172 goto out_end;
1173 }
1174
1175 /**
1176 * gfs2_merge_trans - Merge a new transaction into a cached transaction
1177 * @sdp: the filesystem
1178 * @new: New transaction to be merged
1179 */
1180
gfs2_merge_trans(struct gfs2_sbd * sdp,struct gfs2_trans * new)1181 static void gfs2_merge_trans(struct gfs2_sbd *sdp, struct gfs2_trans *new)
1182 {
1183 struct gfs2_trans *old = sdp->sd_log_tr;
1184
1185 WARN_ON_ONCE(!test_bit(TR_ATTACHED, &old->tr_flags));
1186
1187 old->tr_num_buf_new += new->tr_num_buf_new;
1188 old->tr_num_databuf_new += new->tr_num_databuf_new;
1189 old->tr_num_buf_rm += new->tr_num_buf_rm;
1190 old->tr_num_databuf_rm += new->tr_num_databuf_rm;
1191 old->tr_revokes += new->tr_revokes;
1192 old->tr_num_revoke += new->tr_num_revoke;
1193
1194 list_splice_tail_init(&new->tr_databuf, &old->tr_databuf);
1195 list_splice_tail_init(&new->tr_buf, &old->tr_buf);
1196
1197 spin_lock(&sdp->sd_ail_lock);
1198 list_splice_tail_init(&new->tr_ail1_list, &old->tr_ail1_list);
1199 list_splice_tail_init(&new->tr_ail2_list, &old->tr_ail2_list);
1200 spin_unlock(&sdp->sd_ail_lock);
1201 }
1202
log_refund(struct gfs2_sbd * sdp,struct gfs2_trans * tr)1203 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
1204 {
1205 unsigned int reserved;
1206 unsigned int unused;
1207 unsigned int maxres;
1208
1209 gfs2_log_lock(sdp);
1210
1211 if (sdp->sd_log_tr) {
1212 gfs2_merge_trans(sdp, tr);
1213 } else if (tr->tr_num_buf_new || tr->tr_num_databuf_new) {
1214 gfs2_assert_withdraw(sdp, !test_bit(TR_ONSTACK, &tr->tr_flags));
1215 sdp->sd_log_tr = tr;
1216 set_bit(TR_ATTACHED, &tr->tr_flags);
1217 }
1218
1219 reserved = calc_reserved(sdp);
1220 maxres = sdp->sd_log_blks_reserved + tr->tr_reserved;
1221 gfs2_assert_withdraw(sdp, maxres >= reserved);
1222 unused = maxres - reserved;
1223 if (unused)
1224 gfs2_log_release(sdp, unused);
1225 sdp->sd_log_blks_reserved = reserved;
1226
1227 gfs2_log_unlock(sdp);
1228 }
1229
gfs2_jrnl_flush_reqd(struct gfs2_sbd * sdp)1230 static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
1231 {
1232 return atomic_read(&sdp->sd_log_pinned) +
1233 atomic_read(&sdp->sd_log_blks_needed) >=
1234 atomic_read(&sdp->sd_log_thresh1);
1235 }
1236
gfs2_ail_flush_reqd(struct gfs2_sbd * sdp)1237 static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
1238 {
1239 return sdp->sd_jdesc->jd_blocks -
1240 atomic_read(&sdp->sd_log_blks_free) +
1241 atomic_read(&sdp->sd_log_blks_needed) >=
1242 atomic_read(&sdp->sd_log_thresh2);
1243 }
1244
1245 /**
1246 * gfs2_log_commit - Commit a transaction to the log
1247 * @sdp: the filesystem
1248 * @tr: the transaction
1249 *
1250 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
1251 * or the total number of used blocks (pinned blocks plus AIL blocks)
1252 * is greater than thresh2.
1253 *
1254 * At mount time thresh1 is 2/5ths of journal size, thresh2 is 4/5ths of
1255 * journal size.
1256 *
1257 * Returns: errno
1258 */
1259
gfs2_log_commit(struct gfs2_sbd * sdp,struct gfs2_trans * tr)1260 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
1261 {
1262 log_refund(sdp, tr);
1263
1264 if (gfs2_ail_flush_reqd(sdp) || gfs2_jrnl_flush_reqd(sdp))
1265 wake_up(&sdp->sd_logd_waitq);
1266 }
1267
1268 /**
1269 * gfs2_log_shutdown - write a shutdown header into a journal
1270 * @sdp: the filesystem
1271 *
1272 */
1273
gfs2_log_shutdown(struct gfs2_sbd * sdp)1274 static void gfs2_log_shutdown(struct gfs2_sbd *sdp)
1275 {
1276 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
1277 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
1278 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
1279
1280 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT | GFS2_LFC_SHUTDOWN);
1281 log_pull_tail(sdp);
1282
1283 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
1284 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
1285 }
1286
1287 /**
1288 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
1289 * @data: Pointer to GFS2 superblock
1290 *
1291 * Also, periodically check to make sure that we're using the most recent
1292 * journal index.
1293 */
1294
gfs2_logd(void * data)1295 int gfs2_logd(void *data)
1296 {
1297 struct gfs2_sbd *sdp = data;
1298 unsigned long t = 1;
1299
1300 while (!kthread_should_stop()) {
1301 if (gfs2_withdrawn(sdp))
1302 break;
1303
1304 /* Check for errors writing to the journal */
1305 if (sdp->sd_log_error) {
1306 gfs2_lm(sdp,
1307 "GFS2: fsid=%s: error %d: "
1308 "withdrawing the file system to "
1309 "prevent further damage.\n",
1310 sdp->sd_fsname, sdp->sd_log_error);
1311 gfs2_withdraw(sdp);
1312 break;
1313 }
1314
1315 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
1316 gfs2_ail1_empty(sdp, 0);
1317 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1318 GFS2_LFC_LOGD_JFLUSH_REQD);
1319 }
1320
1321 if (test_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags) ||
1322 gfs2_ail_flush_reqd(sdp)) {
1323 clear_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags);
1324 gfs2_ail1_start(sdp);
1325 gfs2_ail1_wait(sdp);
1326 gfs2_ail1_empty(sdp, 0);
1327 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
1328 GFS2_LFC_LOGD_AIL_FLUSH_REQD);
1329 }
1330
1331 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
1332
1333 try_to_freeze();
1334
1335 t = wait_event_interruptible_timeout(sdp->sd_logd_waitq,
1336 test_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags) ||
1337 gfs2_ail_flush_reqd(sdp) ||
1338 gfs2_jrnl_flush_reqd(sdp) ||
1339 sdp->sd_log_error ||
1340 gfs2_withdrawn(sdp) ||
1341 kthread_should_stop(),
1342 t);
1343 }
1344
1345 return 0;
1346 }
1347
1348