1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
4 *
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
9
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 #include <linux/spinlock.h>
13 #include <linux/completion.h>
14 #include <linux/buffer_head.h>
15 #include <linux/gfs2_ondisk.h>
16 #include <linux/crc32.h>
17 #include <linux/delay.h>
18 #include <linux/kthread.h>
19 #include <linux/freezer.h>
20 #include <linux/bio.h>
21 #include <linux/writeback.h>
22 #include <linux/list_sort.h>
23
24 #include "gfs2.h"
25 #include "incore.h"
26 #include "bmap.h"
27 #include "glock.h"
28 #include "log.h"
29 #include "lops.h"
30 #include "meta_io.h"
31 #include "util.h"
32 #include "dir.h"
33 #include "trace_gfs2.h"
34
35 /**
36 * gfs2_struct2blk - compute stuff
37 * @sdp: the filesystem
38 * @nstruct: the number of structures
39 * @ssize: the size of the structures
40 *
41 * Compute the number of log descriptor blocks needed to hold a certain number
42 * of structures of a certain size.
43 *
44 * Returns: the number of blocks needed (minimum is always 1)
45 */
46
gfs2_struct2blk(struct gfs2_sbd * sdp,unsigned int nstruct,unsigned int ssize)47 unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct,
48 unsigned int ssize)
49 {
50 unsigned int blks;
51 unsigned int first, second;
52
53 blks = 1;
54 first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize;
55
56 if (nstruct > first) {
57 second = (sdp->sd_sb.sb_bsize -
58 sizeof(struct gfs2_meta_header)) / ssize;
59 blks += DIV_ROUND_UP(nstruct - first, second);
60 }
61
62 return blks;
63 }
64
65 /**
66 * gfs2_remove_from_ail - Remove an entry from the ail lists, updating counters
67 * @mapping: The associated mapping (maybe NULL)
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
83 /**
84 * gfs2_ail1_start_one - Start I/O on a part of the AIL
85 * @sdp: the filesystem
86 * @wbc: The writeback control structure
87 * @ai: The ail structure
88 *
89 */
90
gfs2_ail1_start_one(struct gfs2_sbd * sdp,struct writeback_control * wbc,struct gfs2_trans * tr)91 static int gfs2_ail1_start_one(struct gfs2_sbd *sdp,
92 struct writeback_control *wbc,
93 struct gfs2_trans *tr)
94 __releases(&sdp->sd_ail_lock)
95 __acquires(&sdp->sd_ail_lock)
96 {
97 struct gfs2_glock *gl = NULL;
98 struct address_space *mapping;
99 struct gfs2_bufdata *bd, *s;
100 struct buffer_head *bh;
101
102 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list, bd_ail_st_list) {
103 bh = bd->bd_bh;
104
105 gfs2_assert(sdp, bd->bd_tr == tr);
106
107 if (!buffer_busy(bh)) {
108 if (!buffer_uptodate(bh))
109 gfs2_io_error_bh(sdp, bh);
110 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
111 continue;
112 }
113
114 if (!buffer_dirty(bh))
115 continue;
116 if (gl == bd->bd_gl)
117 continue;
118 gl = bd->bd_gl;
119 list_move(&bd->bd_ail_st_list, &tr->tr_ail1_list);
120 mapping = bh->b_page->mapping;
121 if (!mapping)
122 continue;
123 spin_unlock(&sdp->sd_ail_lock);
124 generic_writepages(mapping, wbc);
125 spin_lock(&sdp->sd_ail_lock);
126 if (wbc->nr_to_write <= 0)
127 break;
128 return 1;
129 }
130
131 return 0;
132 }
133
134
135 /**
136 * gfs2_ail1_flush - start writeback of some ail1 entries
137 * @sdp: The super block
138 * @wbc: The writeback control structure
139 *
140 * Writes back some ail1 entries, according to the limits in the
141 * writeback control structure
142 */
143
gfs2_ail1_flush(struct gfs2_sbd * sdp,struct writeback_control * wbc)144 void gfs2_ail1_flush(struct gfs2_sbd *sdp, struct writeback_control *wbc)
145 {
146 struct list_head *head = &sdp->sd_ail1_list;
147 struct gfs2_trans *tr;
148
149 trace_gfs2_ail_flush(sdp, wbc, 1);
150 spin_lock(&sdp->sd_ail_lock);
151 restart:
152 list_for_each_entry_reverse(tr, head, tr_list) {
153 if (wbc->nr_to_write <= 0)
154 break;
155 if (gfs2_ail1_start_one(sdp, wbc, tr))
156 goto restart;
157 }
158 spin_unlock(&sdp->sd_ail_lock);
159 trace_gfs2_ail_flush(sdp, wbc, 0);
160 }
161
162 /**
163 * gfs2_ail1_start - start writeback of all ail1 entries
164 * @sdp: The superblock
165 */
166
gfs2_ail1_start(struct gfs2_sbd * sdp)167 static void gfs2_ail1_start(struct gfs2_sbd *sdp)
168 {
169 struct writeback_control wbc = {
170 .sync_mode = WB_SYNC_NONE,
171 .nr_to_write = LONG_MAX,
172 .range_start = 0,
173 .range_end = LLONG_MAX,
174 };
175
176 return gfs2_ail1_flush(sdp, &wbc);
177 }
178
179 /**
180 * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced
181 * @sdp: the filesystem
182 * @ai: the AIL entry
183 *
184 */
185
gfs2_ail1_empty_one(struct gfs2_sbd * sdp,struct gfs2_trans * tr)186 static void gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
187 {
188 struct gfs2_bufdata *bd, *s;
189 struct buffer_head *bh;
190
191 list_for_each_entry_safe_reverse(bd, s, &tr->tr_ail1_list,
192 bd_ail_st_list) {
193 bh = bd->bd_bh;
194 gfs2_assert(sdp, bd->bd_tr == tr);
195 if (buffer_busy(bh))
196 continue;
197 if (!buffer_uptodate(bh))
198 gfs2_io_error_bh(sdp, bh);
199 list_move(&bd->bd_ail_st_list, &tr->tr_ail2_list);
200 }
201
202 }
203
204 /**
205 * gfs2_ail1_empty - Try to empty the ail1 lists
206 * @sdp: The superblock
207 *
208 * Tries to empty the ail1 lists, starting with the oldest first
209 */
210
gfs2_ail1_empty(struct gfs2_sbd * sdp)211 static int gfs2_ail1_empty(struct gfs2_sbd *sdp)
212 {
213 struct gfs2_trans *tr, *s;
214 int ret;
215
216 spin_lock(&sdp->sd_ail_lock);
217 list_for_each_entry_safe_reverse(tr, s, &sdp->sd_ail1_list, tr_list) {
218 gfs2_ail1_empty_one(sdp, tr);
219 if (list_empty(&tr->tr_ail1_list))
220 list_move(&tr->tr_list, &sdp->sd_ail2_list);
221 else
222 break;
223 }
224 ret = list_empty(&sdp->sd_ail1_list);
225 spin_unlock(&sdp->sd_ail_lock);
226
227 return ret;
228 }
229
gfs2_ail1_wait(struct gfs2_sbd * sdp)230 static void gfs2_ail1_wait(struct gfs2_sbd *sdp)
231 {
232 struct gfs2_trans *tr;
233 struct gfs2_bufdata *bd;
234 struct buffer_head *bh;
235
236 spin_lock(&sdp->sd_ail_lock);
237 list_for_each_entry_reverse(tr, &sdp->sd_ail1_list, tr_list) {
238 list_for_each_entry(bd, &tr->tr_ail1_list, bd_ail_st_list) {
239 bh = bd->bd_bh;
240 if (!buffer_locked(bh))
241 continue;
242 get_bh(bh);
243 spin_unlock(&sdp->sd_ail_lock);
244 wait_on_buffer(bh);
245 brelse(bh);
246 return;
247 }
248 }
249 spin_unlock(&sdp->sd_ail_lock);
250 }
251
252 /**
253 * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced
254 * @sdp: the filesystem
255 * @ai: the AIL entry
256 *
257 */
258
gfs2_ail2_empty_one(struct gfs2_sbd * sdp,struct gfs2_trans * tr)259 static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
260 {
261 struct list_head *head = &tr->tr_ail2_list;
262 struct gfs2_bufdata *bd;
263
264 while (!list_empty(head)) {
265 bd = list_entry(head->prev, struct gfs2_bufdata,
266 bd_ail_st_list);
267 gfs2_assert(sdp, bd->bd_tr == tr);
268 gfs2_remove_from_ail(bd);
269 }
270 }
271
ail2_empty(struct gfs2_sbd * sdp,unsigned int new_tail)272 static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail)
273 {
274 struct gfs2_trans *tr, *safe;
275 unsigned int old_tail = sdp->sd_log_tail;
276 int wrap = (new_tail < old_tail);
277 int a, b, rm;
278
279 spin_lock(&sdp->sd_ail_lock);
280
281 list_for_each_entry_safe(tr, safe, &sdp->sd_ail2_list, tr_list) {
282 a = (old_tail <= tr->tr_first);
283 b = (tr->tr_first < new_tail);
284 rm = (wrap) ? (a || b) : (a && b);
285 if (!rm)
286 continue;
287
288 gfs2_ail2_empty_one(sdp, tr);
289 list_del(&tr->tr_list);
290 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail1_list));
291 gfs2_assert_warn(sdp, list_empty(&tr->tr_ail2_list));
292 kfree(tr);
293 }
294
295 spin_unlock(&sdp->sd_ail_lock);
296 }
297
298 /**
299 * gfs2_log_reserve - Make a log reservation
300 * @sdp: The GFS2 superblock
301 * @blks: The number of blocks to reserve
302 *
303 * Note that we never give out the last few blocks of the journal. Thats
304 * due to the fact that there is a small number of header blocks
305 * associated with each log flush. The exact number can't be known until
306 * flush time, so we ensure that we have just enough free blocks at all
307 * times to avoid running out during a log flush.
308 *
309 * We no longer flush the log here, instead we wake up logd to do that
310 * for us. To avoid the thundering herd and to ensure that we deal fairly
311 * with queued waiters, we use an exclusive wait. This means that when we
312 * get woken with enough journal space to get our reservation, we need to
313 * wake the next waiter on the list.
314 *
315 * Returns: errno
316 */
317
gfs2_log_reserve(struct gfs2_sbd * sdp,unsigned int blks)318 int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks)
319 {
320 unsigned reserved_blks = 6 * (4096 / sdp->sd_vfs->s_blocksize);
321 unsigned wanted = blks + reserved_blks;
322 DEFINE_WAIT(wait);
323 int did_wait = 0;
324 unsigned int free_blocks;
325
326 if (gfs2_assert_warn(sdp, blks) ||
327 gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks))
328 return -EINVAL;
329 retry:
330 free_blocks = atomic_read(&sdp->sd_log_blks_free);
331 if (unlikely(free_blocks <= wanted)) {
332 do {
333 prepare_to_wait_exclusive(&sdp->sd_log_waitq, &wait,
334 TASK_UNINTERRUPTIBLE);
335 wake_up(&sdp->sd_logd_waitq);
336 did_wait = 1;
337 if (atomic_read(&sdp->sd_log_blks_free) <= wanted)
338 io_schedule();
339 free_blocks = atomic_read(&sdp->sd_log_blks_free);
340 } while(free_blocks <= wanted);
341 finish_wait(&sdp->sd_log_waitq, &wait);
342 }
343 if (atomic_cmpxchg(&sdp->sd_log_blks_free, free_blocks,
344 free_blocks - blks) != free_blocks)
345 goto retry;
346 trace_gfs2_log_blocks(sdp, -blks);
347
348 /*
349 * If we waited, then so might others, wake them up _after_ we get
350 * our share of the log.
351 */
352 if (unlikely(did_wait))
353 wake_up(&sdp->sd_log_waitq);
354
355 down_read(&sdp->sd_log_flush_lock);
356
357 return 0;
358 }
359
360 /**
361 * log_distance - Compute distance between two journal blocks
362 * @sdp: The GFS2 superblock
363 * @newer: The most recent journal block of the pair
364 * @older: The older journal block of the pair
365 *
366 * Compute the distance (in the journal direction) between two
367 * blocks in the journal
368 *
369 * Returns: the distance in blocks
370 */
371
log_distance(struct gfs2_sbd * sdp,unsigned int newer,unsigned int older)372 static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer,
373 unsigned int older)
374 {
375 int dist;
376
377 dist = newer - older;
378 if (dist < 0)
379 dist += sdp->sd_jdesc->jd_blocks;
380
381 return dist;
382 }
383
384 /**
385 * calc_reserved - Calculate the number of blocks to reserve when
386 * refunding a transaction's unused buffers.
387 * @sdp: The GFS2 superblock
388 *
389 * This is complex. We need to reserve room for all our currently used
390 * metadata buffers (e.g. normal file I/O rewriting file time stamps) and
391 * all our journaled data buffers for journaled files (e.g. files in the
392 * meta_fs like rindex, or files for which chattr +j was done.)
393 * If we don't reserve enough space, gfs2_log_refund and gfs2_log_flush
394 * will count it as free space (sd_log_blks_free) and corruption will follow.
395 *
396 * We can have metadata bufs and jdata bufs in the same journal. So each
397 * type gets its own log header, for which we need to reserve a block.
398 * In fact, each type has the potential for needing more than one header
399 * in cases where we have more buffers than will fit on a journal page.
400 * Metadata journal entries take up half the space of journaled buffer entries.
401 * Thus, metadata entries have buf_limit (502) and journaled buffers have
402 * databuf_limit (251) before they cause a wrap around.
403 *
404 * Also, we need to reserve blocks for revoke journal entries and one for an
405 * overall header for the lot.
406 *
407 * Returns: the number of blocks reserved
408 */
calc_reserved(struct gfs2_sbd * sdp)409 static unsigned int calc_reserved(struct gfs2_sbd *sdp)
410 {
411 unsigned int reserved = 0;
412 unsigned int mbuf_limit, metabufhdrs_needed;
413 unsigned int dbuf_limit, databufhdrs_needed;
414 unsigned int revokes = 0;
415
416 mbuf_limit = buf_limit(sdp);
417 metabufhdrs_needed = (sdp->sd_log_commited_buf +
418 (mbuf_limit - 1)) / mbuf_limit;
419 dbuf_limit = databuf_limit(sdp);
420 databufhdrs_needed = (sdp->sd_log_commited_databuf +
421 (dbuf_limit - 1)) / dbuf_limit;
422
423 if (sdp->sd_log_commited_revoke > 0)
424 revokes = gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
425 sizeof(u64));
426
427 reserved = sdp->sd_log_commited_buf + metabufhdrs_needed +
428 sdp->sd_log_commited_databuf + databufhdrs_needed +
429 revokes;
430 /* One for the overall header */
431 if (reserved)
432 reserved++;
433 return reserved;
434 }
435
current_tail(struct gfs2_sbd * sdp)436 static unsigned int current_tail(struct gfs2_sbd *sdp)
437 {
438 struct gfs2_trans *tr;
439 unsigned int tail;
440
441 spin_lock(&sdp->sd_ail_lock);
442
443 if (list_empty(&sdp->sd_ail1_list)) {
444 tail = sdp->sd_log_head;
445 } else {
446 tr = list_entry(sdp->sd_ail1_list.prev, struct gfs2_trans,
447 tr_list);
448 tail = tr->tr_first;
449 }
450
451 spin_unlock(&sdp->sd_ail_lock);
452
453 return tail;
454 }
455
log_pull_tail(struct gfs2_sbd * sdp,unsigned int new_tail)456 static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail)
457 {
458 unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail);
459
460 ail2_empty(sdp, new_tail);
461
462 atomic_add(dist, &sdp->sd_log_blks_free);
463 trace_gfs2_log_blocks(sdp, dist);
464 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
465 sdp->sd_jdesc->jd_blocks);
466
467 sdp->sd_log_tail = new_tail;
468 }
469
470
log_flush_wait(struct gfs2_sbd * sdp)471 static void log_flush_wait(struct gfs2_sbd *sdp)
472 {
473 DEFINE_WAIT(wait);
474
475 if (atomic_read(&sdp->sd_log_in_flight)) {
476 do {
477 prepare_to_wait(&sdp->sd_log_flush_wait, &wait,
478 TASK_UNINTERRUPTIBLE);
479 if (atomic_read(&sdp->sd_log_in_flight))
480 io_schedule();
481 } while(atomic_read(&sdp->sd_log_in_flight));
482 finish_wait(&sdp->sd_log_flush_wait, &wait);
483 }
484 }
485
ip_cmp(void * priv,struct list_head * a,struct list_head * b)486 static int ip_cmp(void *priv, struct list_head *a, struct list_head *b)
487 {
488 struct gfs2_inode *ipa, *ipb;
489
490 ipa = list_entry(a, struct gfs2_inode, i_ordered);
491 ipb = list_entry(b, struct gfs2_inode, i_ordered);
492
493 if (ipa->i_no_addr < ipb->i_no_addr)
494 return -1;
495 if (ipa->i_no_addr > ipb->i_no_addr)
496 return 1;
497 return 0;
498 }
499
gfs2_ordered_write(struct gfs2_sbd * sdp)500 static void gfs2_ordered_write(struct gfs2_sbd *sdp)
501 {
502 struct gfs2_inode *ip;
503 LIST_HEAD(written);
504
505 spin_lock(&sdp->sd_ordered_lock);
506 list_sort(NULL, &sdp->sd_log_le_ordered, &ip_cmp);
507 while (!list_empty(&sdp->sd_log_le_ordered)) {
508 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
509 list_move(&ip->i_ordered, &written);
510 if (ip->i_inode.i_mapping->nrpages == 0)
511 continue;
512 spin_unlock(&sdp->sd_ordered_lock);
513 filemap_fdatawrite(ip->i_inode.i_mapping);
514 spin_lock(&sdp->sd_ordered_lock);
515 }
516 list_splice(&written, &sdp->sd_log_le_ordered);
517 spin_unlock(&sdp->sd_ordered_lock);
518 }
519
gfs2_ordered_wait(struct gfs2_sbd * sdp)520 static void gfs2_ordered_wait(struct gfs2_sbd *sdp)
521 {
522 struct gfs2_inode *ip;
523
524 spin_lock(&sdp->sd_ordered_lock);
525 while (!list_empty(&sdp->sd_log_le_ordered)) {
526 ip = list_entry(sdp->sd_log_le_ordered.next, struct gfs2_inode, i_ordered);
527 list_del(&ip->i_ordered);
528 WARN_ON(!test_and_clear_bit(GIF_ORDERED, &ip->i_flags));
529 if (ip->i_inode.i_mapping->nrpages == 0)
530 continue;
531 spin_unlock(&sdp->sd_ordered_lock);
532 filemap_fdatawait(ip->i_inode.i_mapping);
533 spin_lock(&sdp->sd_ordered_lock);
534 }
535 spin_unlock(&sdp->sd_ordered_lock);
536 }
537
gfs2_ordered_del_inode(struct gfs2_inode * ip)538 void gfs2_ordered_del_inode(struct gfs2_inode *ip)
539 {
540 struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
541
542 spin_lock(&sdp->sd_ordered_lock);
543 if (test_and_clear_bit(GIF_ORDERED, &ip->i_flags))
544 list_del(&ip->i_ordered);
545 spin_unlock(&sdp->sd_ordered_lock);
546 }
547
548 /**
549 * log_write_header - Get and initialize a journal header buffer
550 * @sdp: The GFS2 superblock
551 *
552 * Returns: the initialized log buffer descriptor
553 */
554
log_write_header(struct gfs2_sbd * sdp,u32 flags)555 static void log_write_header(struct gfs2_sbd *sdp, u32 flags)
556 {
557 struct gfs2_log_header *lh;
558 unsigned int tail;
559 u32 hash;
560 int rw = WRITE_FLUSH_FUA | REQ_META;
561 struct page *page = mempool_alloc(gfs2_page_pool, GFP_NOIO);
562 lh = page_address(page);
563 clear_page(lh);
564
565 gfs2_ail1_empty(sdp);
566 tail = current_tail(sdp);
567
568 lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
569 lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH);
570 lh->lh_header.__pad0 = cpu_to_be64(0);
571 lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH);
572 lh->lh_header.mh_jid = cpu_to_be32(sdp->sd_jdesc->jd_jid);
573 lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++);
574 lh->lh_flags = cpu_to_be32(flags);
575 lh->lh_tail = cpu_to_be32(tail);
576 lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head);
577 hash = gfs2_disk_hash(page_address(page), sizeof(struct gfs2_log_header));
578 lh->lh_hash = cpu_to_be32(hash);
579
580 if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags)) {
581 gfs2_ordered_wait(sdp);
582 log_flush_wait(sdp);
583 rw = WRITE_SYNC | REQ_META | REQ_PRIO;
584 }
585
586 sdp->sd_log_idle = (tail == sdp->sd_log_flush_head);
587 gfs2_log_write_page(sdp, page);
588 gfs2_log_flush_bio(sdp, rw);
589 log_flush_wait(sdp);
590
591 if (sdp->sd_log_tail != tail)
592 log_pull_tail(sdp, tail);
593 }
594
595 /**
596 * gfs2_log_flush - flush incore transaction(s)
597 * @sdp: the filesystem
598 * @gl: The glock structure to flush. If NULL, flush the whole incore log
599 *
600 */
601
gfs2_log_flush(struct gfs2_sbd * sdp,struct gfs2_glock * gl)602 void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
603 {
604 struct gfs2_trans *tr;
605
606 down_write(&sdp->sd_log_flush_lock);
607
608 /* Log might have been flushed while we waited for the flush lock */
609 if (gl && !test_bit(GLF_LFLUSH, &gl->gl_flags)) {
610 up_write(&sdp->sd_log_flush_lock);
611 return;
612 }
613 trace_gfs2_log_flush(sdp, 1);
614
615 tr = sdp->sd_log_tr;
616 if (tr) {
617 sdp->sd_log_tr = NULL;
618 INIT_LIST_HEAD(&tr->tr_ail1_list);
619 INIT_LIST_HEAD(&tr->tr_ail2_list);
620 }
621
622 if (sdp->sd_log_num_buf != sdp->sd_log_commited_buf) {
623 printk(KERN_INFO "GFS2: log buf %u %u\n", sdp->sd_log_num_buf,
624 sdp->sd_log_commited_buf);
625 gfs2_assert_withdraw(sdp, 0);
626 }
627 if (sdp->sd_log_num_databuf != sdp->sd_log_commited_databuf) {
628 printk(KERN_INFO "GFS2: log databuf %u %u\n",
629 sdp->sd_log_num_databuf, sdp->sd_log_commited_databuf);
630 gfs2_assert_withdraw(sdp, 0);
631 }
632 gfs2_assert_withdraw(sdp,
633 sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke);
634
635 sdp->sd_log_flush_head = sdp->sd_log_head;
636 sdp->sd_log_flush_wrapped = 0;
637 if (tr)
638 tr->tr_first = sdp->sd_log_flush_head;
639
640 gfs2_ordered_write(sdp);
641 lops_before_commit(sdp);
642 gfs2_log_flush_bio(sdp, WRITE);
643
644 if (sdp->sd_log_head != sdp->sd_log_flush_head) {
645 log_write_header(sdp, 0);
646 } else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle){
647 atomic_dec(&sdp->sd_log_blks_free); /* Adjust for unreserved buffer */
648 trace_gfs2_log_blocks(sdp, -1);
649 log_write_header(sdp, 0);
650 }
651 lops_after_commit(sdp, tr);
652
653 gfs2_log_lock(sdp);
654 sdp->sd_log_head = sdp->sd_log_flush_head;
655 sdp->sd_log_blks_reserved = 0;
656 sdp->sd_log_commited_buf = 0;
657 sdp->sd_log_commited_databuf = 0;
658 sdp->sd_log_commited_revoke = 0;
659
660 spin_lock(&sdp->sd_ail_lock);
661 if (tr && !list_empty(&tr->tr_ail1_list)) {
662 list_add(&tr->tr_list, &sdp->sd_ail1_list);
663 tr = NULL;
664 }
665 spin_unlock(&sdp->sd_ail_lock);
666 gfs2_log_unlock(sdp);
667 trace_gfs2_log_flush(sdp, 0);
668 up_write(&sdp->sd_log_flush_lock);
669
670 kfree(tr);
671 }
672
log_refund(struct gfs2_sbd * sdp,struct gfs2_trans * tr)673 static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
674 {
675 unsigned int reserved;
676 unsigned int unused;
677
678 gfs2_log_lock(sdp);
679
680 sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm;
681 sdp->sd_log_commited_databuf += tr->tr_num_databuf_new -
682 tr->tr_num_databuf_rm;
683 gfs2_assert_withdraw(sdp, (((int)sdp->sd_log_commited_buf) >= 0) ||
684 (((int)sdp->sd_log_commited_databuf) >= 0));
685 sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm;
686 reserved = calc_reserved(sdp);
687 gfs2_assert_withdraw(sdp, sdp->sd_log_blks_reserved + tr->tr_reserved >= reserved);
688 unused = sdp->sd_log_blks_reserved - reserved + tr->tr_reserved;
689 atomic_add(unused, &sdp->sd_log_blks_free);
690 trace_gfs2_log_blocks(sdp, unused);
691 gfs2_assert_withdraw(sdp, atomic_read(&sdp->sd_log_blks_free) <=
692 sdp->sd_jdesc->jd_blocks);
693 sdp->sd_log_blks_reserved = reserved;
694
695 if (sdp->sd_log_tr == NULL &&
696 (tr->tr_num_buf_new || tr->tr_num_databuf_new)) {
697 gfs2_assert_withdraw(sdp, tr->tr_t_gh.gh_gl);
698 sdp->sd_log_tr = tr;
699 tr->tr_attached = 1;
700 }
701 gfs2_log_unlock(sdp);
702 }
703
704 /**
705 * gfs2_log_commit - Commit a transaction to the log
706 * @sdp: the filesystem
707 * @tr: the transaction
708 *
709 * We wake up gfs2_logd if the number of pinned blocks exceed thresh1
710 * or the total number of used blocks (pinned blocks plus AIL blocks)
711 * is greater than thresh2.
712 *
713 * At mount time thresh1 is 1/3rd of journal size, thresh2 is 2/3rd of
714 * journal size.
715 *
716 * Returns: errno
717 */
718
gfs2_log_commit(struct gfs2_sbd * sdp,struct gfs2_trans * tr)719 void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
720 {
721 log_refund(sdp, tr);
722
723 if (atomic_read(&sdp->sd_log_pinned) > atomic_read(&sdp->sd_log_thresh1) ||
724 ((sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free)) >
725 atomic_read(&sdp->sd_log_thresh2)))
726 wake_up(&sdp->sd_logd_waitq);
727 }
728
729 /**
730 * gfs2_log_shutdown - write a shutdown header into a journal
731 * @sdp: the filesystem
732 *
733 */
734
gfs2_log_shutdown(struct gfs2_sbd * sdp)735 void gfs2_log_shutdown(struct gfs2_sbd *sdp)
736 {
737 down_write(&sdp->sd_log_flush_lock);
738
739 gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved);
740 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf);
741 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke);
742 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg);
743 gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf);
744 gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list));
745
746 sdp->sd_log_flush_head = sdp->sd_log_head;
747 sdp->sd_log_flush_wrapped = 0;
748
749 log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT);
750
751 gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
752 gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail);
753 gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list));
754
755 sdp->sd_log_head = sdp->sd_log_flush_head;
756 sdp->sd_log_tail = sdp->sd_log_head;
757
758 up_write(&sdp->sd_log_flush_lock);
759 }
760
761
762 /**
763 * gfs2_meta_syncfs - sync all the buffers in a filesystem
764 * @sdp: the filesystem
765 *
766 */
767
gfs2_meta_syncfs(struct gfs2_sbd * sdp)768 void gfs2_meta_syncfs(struct gfs2_sbd *sdp)
769 {
770 gfs2_log_flush(sdp, NULL);
771 for (;;) {
772 gfs2_ail1_start(sdp);
773 gfs2_ail1_wait(sdp);
774 if (gfs2_ail1_empty(sdp))
775 break;
776 }
777 gfs2_log_flush(sdp, NULL);
778 }
779
gfs2_jrnl_flush_reqd(struct gfs2_sbd * sdp)780 static inline int gfs2_jrnl_flush_reqd(struct gfs2_sbd *sdp)
781 {
782 return (atomic_read(&sdp->sd_log_pinned) >= atomic_read(&sdp->sd_log_thresh1));
783 }
784
gfs2_ail_flush_reqd(struct gfs2_sbd * sdp)785 static inline int gfs2_ail_flush_reqd(struct gfs2_sbd *sdp)
786 {
787 unsigned int used_blocks = sdp->sd_jdesc->jd_blocks - atomic_read(&sdp->sd_log_blks_free);
788 return used_blocks >= atomic_read(&sdp->sd_log_thresh2);
789 }
790
791 /**
792 * gfs2_logd - Update log tail as Active Items get flushed to in-place blocks
793 * @sdp: Pointer to GFS2 superblock
794 *
795 * Also, periodically check to make sure that we're using the most recent
796 * journal index.
797 */
798
gfs2_logd(void * data)799 int gfs2_logd(void *data)
800 {
801 struct gfs2_sbd *sdp = data;
802 unsigned long t = 1;
803 DEFINE_WAIT(wait);
804
805 while (!kthread_should_stop()) {
806
807 if (gfs2_jrnl_flush_reqd(sdp) || t == 0) {
808 gfs2_ail1_empty(sdp);
809 gfs2_log_flush(sdp, NULL);
810 }
811
812 if (gfs2_ail_flush_reqd(sdp)) {
813 gfs2_ail1_start(sdp);
814 gfs2_ail1_wait(sdp);
815 gfs2_ail1_empty(sdp);
816 gfs2_log_flush(sdp, NULL);
817 }
818
819 if (!gfs2_ail_flush_reqd(sdp))
820 wake_up(&sdp->sd_log_waitq);
821
822 t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
823
824 try_to_freeze();
825
826 do {
827 prepare_to_wait(&sdp->sd_logd_waitq, &wait,
828 TASK_INTERRUPTIBLE);
829 if (!gfs2_ail_flush_reqd(sdp) &&
830 !gfs2_jrnl_flush_reqd(sdp) &&
831 !kthread_should_stop())
832 t = schedule_timeout(t);
833 } while(t && !gfs2_ail_flush_reqd(sdp) &&
834 !gfs2_jrnl_flush_reqd(sdp) &&
835 !kthread_should_stop());
836 finish_wait(&sdp->sd_logd_waitq, &wait);
837 }
838
839 return 0;
840 }
841
842