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1/*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18#include "xfs.h"
19#include "xfs_fs.h"
20#include "xfs_types.h"
21#include "xfs_bit.h"
22#include "xfs_log.h"
23#include "xfs_inum.h"
24#include "xfs_trans.h"
25#include "xfs_sb.h"
26#include "xfs_ag.h"
27#include "xfs_mount.h"
28#include "xfs_buf_item.h"
29#include "xfs_trans_priv.h"
30#include "xfs_error.h"
31#include "xfs_trace.h"
32
33
34kmem_zone_t *xfs_buf_item_zone;
35
36static inline struct xfs_buf_log_item *BUF_ITEM(struct xfs_log_item *lip)
37{
38 return container_of(lip, struct xfs_buf_log_item, bli_item);
39}
40
41
42#ifdef XFS_TRANS_DEBUG
43/*
44 * This function uses an alternate strategy for tracking the bytes
45 * that the user requests to be logged. This can then be used
46 * in conjunction with the bli_orig array in the buf log item to
47 * catch bugs in our callers' code.
48 *
49 * We also double check the bits set in xfs_buf_item_log using a
50 * simple algorithm to check that every byte is accounted for.
51 */
52STATIC void
53xfs_buf_item_log_debug(
54 xfs_buf_log_item_t *bip,
55 uint first,
56 uint last)
57{
58 uint x;
59 uint byte;
60 uint nbytes;
61 uint chunk_num;
62 uint word_num;
63 uint bit_num;
64 uint bit_set;
65 uint *wordp;
66
67 ASSERT(bip->bli_logged != NULL);
68 byte = first;
69 nbytes = last - first + 1;
70 bfset(bip->bli_logged, first, nbytes);
71 for (x = 0; x < nbytes; x++) {
72 chunk_num = byte >> XFS_BLF_SHIFT;
73 word_num = chunk_num >> BIT_TO_WORD_SHIFT;
74 bit_num = chunk_num & (NBWORD - 1);
75 wordp = &(bip->bli_format.blf_data_map[word_num]);
76 bit_set = *wordp & (1 << bit_num);
77 ASSERT(bit_set);
78 byte++;
79 }
80}
81
82/*
83 * This function is called when we flush something into a buffer without
84 * logging it. This happens for things like inodes which are logged
85 * separately from the buffer.
86 */
87void
88xfs_buf_item_flush_log_debug(
89 xfs_buf_t *bp,
90 uint first,
91 uint last)
92{
93 xfs_buf_log_item_t *bip = bp->b_fspriv;
94 uint nbytes;
95
96 if (bip == NULL || (bip->bli_item.li_type != XFS_LI_BUF))
97 return;
98
99 ASSERT(bip->bli_logged != NULL);
100 nbytes = last - first + 1;
101 bfset(bip->bli_logged, first, nbytes);
102}
103
104/*
105 * This function is called to verify that our callers have logged
106 * all the bytes that they changed.
107 *
108 * It does this by comparing the original copy of the buffer stored in
109 * the buf log item's bli_orig array to the current copy of the buffer
110 * and ensuring that all bytes which mismatch are set in the bli_logged
111 * array of the buf log item.
112 */
113STATIC void
114xfs_buf_item_log_check(
115 xfs_buf_log_item_t *bip)
116{
117 char *orig;
118 char *buffer;
119 int x;
120 xfs_buf_t *bp;
121
122 ASSERT(bip->bli_orig != NULL);
123 ASSERT(bip->bli_logged != NULL);
124
125 bp = bip->bli_buf;
126 ASSERT(XFS_BUF_COUNT(bp) > 0);
127 ASSERT(bp->b_addr != NULL);
128 orig = bip->bli_orig;
129 buffer = bp->b_addr;
130 for (x = 0; x < XFS_BUF_COUNT(bp); x++) {
131 if (orig[x] != buffer[x] && !btst(bip->bli_logged, x)) {
132 xfs_emerg(bp->b_mount,
133 "%s: bip %x buffer %x orig %x index %d",
134 __func__, bip, bp, orig, x);
135 ASSERT(0);
136 }
137 }
138}
139#else
140#define xfs_buf_item_log_debug(x,y,z)
141#define xfs_buf_item_log_check(x)
142#endif
143
144STATIC void xfs_buf_do_callbacks(struct xfs_buf *bp);
145
146/*
147 * This returns the number of log iovecs needed to log the
148 * given buf log item.
149 *
150 * It calculates this as 1 iovec for the buf log format structure
151 * and 1 for each stretch of non-contiguous chunks to be logged.
152 * Contiguous chunks are logged in a single iovec.
153 *
154 * If the XFS_BLI_STALE flag has been set, then log nothing.
155 */
156STATIC uint
157xfs_buf_item_size(
158 struct xfs_log_item *lip)
159{
160 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
161 struct xfs_buf *bp = bip->bli_buf;
162 uint nvecs;
163 int next_bit;
164 int last_bit;
165
166 ASSERT(atomic_read(&bip->bli_refcount) > 0);
167 if (bip->bli_flags & XFS_BLI_STALE) {
168 /*
169 * The buffer is stale, so all we need to log
170 * is the buf log format structure with the
171 * cancel flag in it.
172 */
173 trace_xfs_buf_item_size_stale(bip);
174 ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
175 return 1;
176 }
177
178 ASSERT(bip->bli_flags & XFS_BLI_LOGGED);
179 nvecs = 1;
180 last_bit = xfs_next_bit(bip->bli_format.blf_data_map,
181 bip->bli_format.blf_map_size, 0);
182 ASSERT(last_bit != -1);
183 nvecs++;
184 while (last_bit != -1) {
185 /*
186 * This takes the bit number to start looking from and
187 * returns the next set bit from there. It returns -1
188 * if there are no more bits set or the start bit is
189 * beyond the end of the bitmap.
190 */
191 next_bit = xfs_next_bit(bip->bli_format.blf_data_map,
192 bip->bli_format.blf_map_size,
193 last_bit + 1);
194 /*
195 * If we run out of bits, leave the loop,
196 * else if we find a new set of bits bump the number of vecs,
197 * else keep scanning the current set of bits.
198 */
199 if (next_bit == -1) {
200 last_bit = -1;
201 } else if (next_bit != last_bit + 1) {
202 last_bit = next_bit;
203 nvecs++;
204 } else if (xfs_buf_offset(bp, next_bit * XFS_BLF_CHUNK) !=
205 (xfs_buf_offset(bp, last_bit * XFS_BLF_CHUNK) +
206 XFS_BLF_CHUNK)) {
207 last_bit = next_bit;
208 nvecs++;
209 } else {
210 last_bit++;
211 }
212 }
213
214 trace_xfs_buf_item_size(bip);
215 return nvecs;
216}
217
218/*
219 * This is called to fill in the vector of log iovecs for the
220 * given log buf item. It fills the first entry with a buf log
221 * format structure, and the rest point to contiguous chunks
222 * within the buffer.
223 */
224STATIC void
225xfs_buf_item_format(
226 struct xfs_log_item *lip,
227 struct xfs_log_iovec *vecp)
228{
229 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
230 struct xfs_buf *bp = bip->bli_buf;
231 uint base_size;
232 uint nvecs;
233 int first_bit;
234 int last_bit;
235 int next_bit;
236 uint nbits;
237 uint buffer_offset;
238
239 ASSERT(atomic_read(&bip->bli_refcount) > 0);
240 ASSERT((bip->bli_flags & XFS_BLI_LOGGED) ||
241 (bip->bli_flags & XFS_BLI_STALE));
242
243 /*
244 * The size of the base structure is the size of the
245 * declared structure plus the space for the extra words
246 * of the bitmap. We subtract one from the map size, because
247 * the first element of the bitmap is accounted for in the
248 * size of the base structure.
249 */
250 base_size =
251 (uint)(sizeof(xfs_buf_log_format_t) +
252 ((bip->bli_format.blf_map_size - 1) * sizeof(uint)));
253 vecp->i_addr = &bip->bli_format;
254 vecp->i_len = base_size;
255 vecp->i_type = XLOG_REG_TYPE_BFORMAT;
256 vecp++;
257 nvecs = 1;
258
259 /*
260 * If it is an inode buffer, transfer the in-memory state to the
261 * format flags and clear the in-memory state. We do not transfer
262 * this state if the inode buffer allocation has not yet been committed
263 * to the log as setting the XFS_BLI_INODE_BUF flag will prevent
264 * correct replay of the inode allocation.
265 */
266 if (bip->bli_flags & XFS_BLI_INODE_BUF) {
267 if (!((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) &&
268 xfs_log_item_in_current_chkpt(lip)))
269 bip->bli_format.blf_flags |= XFS_BLF_INODE_BUF;
270 bip->bli_flags &= ~XFS_BLI_INODE_BUF;
271 }
272
273 if (bip->bli_flags & XFS_BLI_STALE) {
274 /*
275 * The buffer is stale, so all we need to log
276 * is the buf log format structure with the
277 * cancel flag in it.
278 */
279 trace_xfs_buf_item_format_stale(bip);
280 ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
281 bip->bli_format.blf_size = nvecs;
282 return;
283 }
284
285 /*
286 * Fill in an iovec for each set of contiguous chunks.
287 */
288 first_bit = xfs_next_bit(bip->bli_format.blf_data_map,
289 bip->bli_format.blf_map_size, 0);
290 ASSERT(first_bit != -1);
291 last_bit = first_bit;
292 nbits = 1;
293 for (;;) {
294 /*
295 * This takes the bit number to start looking from and
296 * returns the next set bit from there. It returns -1
297 * if there are no more bits set or the start bit is
298 * beyond the end of the bitmap.
299 */
300 next_bit = xfs_next_bit(bip->bli_format.blf_data_map,
301 bip->bli_format.blf_map_size,
302 (uint)last_bit + 1);
303 /*
304 * If we run out of bits fill in the last iovec and get
305 * out of the loop.
306 * Else if we start a new set of bits then fill in the
307 * iovec for the series we were looking at and start
308 * counting the bits in the new one.
309 * Else we're still in the same set of bits so just
310 * keep counting and scanning.
311 */
312 if (next_bit == -1) {
313 buffer_offset = first_bit * XFS_BLF_CHUNK;
314 vecp->i_addr = xfs_buf_offset(bp, buffer_offset);
315 vecp->i_len = nbits * XFS_BLF_CHUNK;
316 vecp->i_type = XLOG_REG_TYPE_BCHUNK;
317 nvecs++;
318 break;
319 } else if (next_bit != last_bit + 1) {
320 buffer_offset = first_bit * XFS_BLF_CHUNK;
321 vecp->i_addr = xfs_buf_offset(bp, buffer_offset);
322 vecp->i_len = nbits * XFS_BLF_CHUNK;
323 vecp->i_type = XLOG_REG_TYPE_BCHUNK;
324 nvecs++;
325 vecp++;
326 first_bit = next_bit;
327 last_bit = next_bit;
328 nbits = 1;
329 } else if (xfs_buf_offset(bp, next_bit << XFS_BLF_SHIFT) !=
330 (xfs_buf_offset(bp, last_bit << XFS_BLF_SHIFT) +
331 XFS_BLF_CHUNK)) {
332 buffer_offset = first_bit * XFS_BLF_CHUNK;
333 vecp->i_addr = xfs_buf_offset(bp, buffer_offset);
334 vecp->i_len = nbits * XFS_BLF_CHUNK;
335 vecp->i_type = XLOG_REG_TYPE_BCHUNK;
336/* You would think we need to bump the nvecs here too, but we do not
337 * this number is used by recovery, and it gets confused by the boundary
338 * split here
339 * nvecs++;
340 */
341 vecp++;
342 first_bit = next_bit;
343 last_bit = next_bit;
344 nbits = 1;
345 } else {
346 last_bit++;
347 nbits++;
348 }
349 }
350 bip->bli_format.blf_size = nvecs;
351
352 /*
353 * Check to make sure everything is consistent.
354 */
355 trace_xfs_buf_item_format(bip);
356 xfs_buf_item_log_check(bip);
357}
358
359/*
360 * This is called to pin the buffer associated with the buf log item in memory
361 * so it cannot be written out.
362 *
363 * We also always take a reference to the buffer log item here so that the bli
364 * is held while the item is pinned in memory. This means that we can
365 * unconditionally drop the reference count a transaction holds when the
366 * transaction is completed.
367 */
368STATIC void
369xfs_buf_item_pin(
370 struct xfs_log_item *lip)
371{
372 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
373
374 ASSERT(atomic_read(&bip->bli_refcount) > 0);
375 ASSERT((bip->bli_flags & XFS_BLI_LOGGED) ||
376 (bip->bli_flags & XFS_BLI_STALE));
377
378 trace_xfs_buf_item_pin(bip);
379
380 atomic_inc(&bip->bli_refcount);
381 atomic_inc(&bip->bli_buf->b_pin_count);
382}
383
384/*
385 * This is called to unpin the buffer associated with the buf log
386 * item which was previously pinned with a call to xfs_buf_item_pin().
387 *
388 * Also drop the reference to the buf item for the current transaction.
389 * If the XFS_BLI_STALE flag is set and we are the last reference,
390 * then free up the buf log item and unlock the buffer.
391 *
392 * If the remove flag is set we are called from uncommit in the
393 * forced-shutdown path. If that is true and the reference count on
394 * the log item is going to drop to zero we need to free the item's
395 * descriptor in the transaction.
396 */
397STATIC void
398xfs_buf_item_unpin(
399 struct xfs_log_item *lip,
400 int remove)
401{
402 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
403 xfs_buf_t *bp = bip->bli_buf;
404 struct xfs_ail *ailp = lip->li_ailp;
405 int stale = bip->bli_flags & XFS_BLI_STALE;
406 int freed;
407
408 ASSERT(bp->b_fspriv == bip);
409 ASSERT(atomic_read(&bip->bli_refcount) > 0);
410
411 trace_xfs_buf_item_unpin(bip);
412
413 freed = atomic_dec_and_test(&bip->bli_refcount);
414
415 if (atomic_dec_and_test(&bp->b_pin_count))
416 wake_up_all(&bp->b_waiters);
417
418 if (freed && stale) {
419 ASSERT(bip->bli_flags & XFS_BLI_STALE);
420 ASSERT(xfs_buf_islocked(bp));
421 ASSERT(!(XFS_BUF_ISDELAYWRITE(bp)));
422 ASSERT(XFS_BUF_ISSTALE(bp));
423 ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
424
425 trace_xfs_buf_item_unpin_stale(bip);
426
427 if (remove) {
428 /*
429 * If we are in a transaction context, we have to
430 * remove the log item from the transaction as we are
431 * about to release our reference to the buffer. If we
432 * don't, the unlock that occurs later in
433 * xfs_trans_uncommit() will try to reference the
434 * buffer which we no longer have a hold on.
435 */
436 if (lip->li_desc)
437 xfs_trans_del_item(lip);
438
439 /*
440 * Since the transaction no longer refers to the buffer,
441 * the buffer should no longer refer to the transaction.
442 */
443 bp->b_transp = NULL;
444 }
445
446 /*
447 * If we get called here because of an IO error, we may
448 * or may not have the item on the AIL. xfs_trans_ail_delete()
449 * will take care of that situation.
450 * xfs_trans_ail_delete() drops the AIL lock.
451 */
452 if (bip->bli_flags & XFS_BLI_STALE_INODE) {
453 xfs_buf_do_callbacks(bp);
454 bp->b_fspriv = NULL;
455 bp->b_iodone = NULL;
456 } else {
457 spin_lock(&ailp->xa_lock);
458 xfs_trans_ail_delete(ailp, (xfs_log_item_t *)bip);
459 xfs_buf_item_relse(bp);
460 ASSERT(bp->b_fspriv == NULL);
461 }
462 xfs_buf_relse(bp);
463 }
464}
465
466/*
467 * This is called to attempt to lock the buffer associated with this
468 * buf log item. Don't sleep on the buffer lock. If we can't get
469 * the lock right away, return 0. If we can get the lock, take a
470 * reference to the buffer. If this is a delayed write buffer that
471 * needs AIL help to be written back, invoke the pushbuf routine
472 * rather than the normal success path.
473 */
474STATIC uint
475xfs_buf_item_trylock(
476 struct xfs_log_item *lip)
477{
478 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
479 struct xfs_buf *bp = bip->bli_buf;
480
481 if (xfs_buf_ispinned(bp))
482 return XFS_ITEM_PINNED;
483 if (!xfs_buf_trylock(bp))
484 return XFS_ITEM_LOCKED;
485
486 /* take a reference to the buffer. */
487 xfs_buf_hold(bp);
488
489 ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
490 trace_xfs_buf_item_trylock(bip);
491 if (XFS_BUF_ISDELAYWRITE(bp))
492 return XFS_ITEM_PUSHBUF;
493 return XFS_ITEM_SUCCESS;
494}
495
496/*
497 * Release the buffer associated with the buf log item. If there is no dirty
498 * logged data associated with the buffer recorded in the buf log item, then
499 * free the buf log item and remove the reference to it in the buffer.
500 *
501 * This call ignores the recursion count. It is only called when the buffer
502 * should REALLY be unlocked, regardless of the recursion count.
503 *
504 * We unconditionally drop the transaction's reference to the log item. If the
505 * item was logged, then another reference was taken when it was pinned, so we
506 * can safely drop the transaction reference now. This also allows us to avoid
507 * potential races with the unpin code freeing the bli by not referencing the
508 * bli after we've dropped the reference count.
509 *
510 * If the XFS_BLI_HOLD flag is set in the buf log item, then free the log item
511 * if necessary but do not unlock the buffer. This is for support of
512 * xfs_trans_bhold(). Make sure the XFS_BLI_HOLD field is cleared if we don't
513 * free the item.
514 */
515STATIC void
516xfs_buf_item_unlock(
517 struct xfs_log_item *lip)
518{
519 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
520 struct xfs_buf *bp = bip->bli_buf;
521 int aborted;
522 uint hold;
523
524 /* Clear the buffer's association with this transaction. */
525 bp->b_transp = NULL;
526
527 /*
528 * If this is a transaction abort, don't return early. Instead, allow
529 * the brelse to happen. Normally it would be done for stale
530 * (cancelled) buffers at unpin time, but we'll never go through the
531 * pin/unpin cycle if we abort inside commit.
532 */
533 aborted = (lip->li_flags & XFS_LI_ABORTED) != 0;
534
535 /*
536 * Before possibly freeing the buf item, determine if we should
537 * release the buffer at the end of this routine.
538 */
539 hold = bip->bli_flags & XFS_BLI_HOLD;
540
541 /* Clear the per transaction state. */
542 bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD);
543
544 /*
545 * If the buf item is marked stale, then don't do anything. We'll
546 * unlock the buffer and free the buf item when the buffer is unpinned
547 * for the last time.
548 */
549 if (bip->bli_flags & XFS_BLI_STALE) {
550 trace_xfs_buf_item_unlock_stale(bip);
551 ASSERT(bip->bli_format.blf_flags & XFS_BLF_CANCEL);
552 if (!aborted) {
553 atomic_dec(&bip->bli_refcount);
554 return;
555 }
556 }
557
558 trace_xfs_buf_item_unlock(bip);
559
560 /*
561 * If the buf item isn't tracking any data, free it, otherwise drop the
562 * reference we hold to it.
563 */
564 if (xfs_bitmap_empty(bip->bli_format.blf_data_map,
565 bip->bli_format.blf_map_size))
566 xfs_buf_item_relse(bp);
567 else
568 atomic_dec(&bip->bli_refcount);
569
570 if (!hold)
571 xfs_buf_relse(bp);
572}
573
574/*
575 * This is called to find out where the oldest active copy of the
576 * buf log item in the on disk log resides now that the last log
577 * write of it completed at the given lsn.
578 * We always re-log all the dirty data in a buffer, so usually the
579 * latest copy in the on disk log is the only one that matters. For
580 * those cases we simply return the given lsn.
581 *
582 * The one exception to this is for buffers full of newly allocated
583 * inodes. These buffers are only relogged with the XFS_BLI_INODE_BUF
584 * flag set, indicating that only the di_next_unlinked fields from the
585 * inodes in the buffers will be replayed during recovery. If the
586 * original newly allocated inode images have not yet been flushed
587 * when the buffer is so relogged, then we need to make sure that we
588 * keep the old images in the 'active' portion of the log. We do this
589 * by returning the original lsn of that transaction here rather than
590 * the current one.
591 */
592STATIC xfs_lsn_t
593xfs_buf_item_committed(
594 struct xfs_log_item *lip,
595 xfs_lsn_t lsn)
596{
597 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
598
599 trace_xfs_buf_item_committed(bip);
600
601 if ((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) && lip->li_lsn != 0)
602 return lip->li_lsn;
603 return lsn;
604}
605
606/*
607 * The buffer is locked, but is not a delayed write buffer. This happens
608 * if we race with IO completion and hence we don't want to try to write it
609 * again. Just release the buffer.
610 */
611STATIC void
612xfs_buf_item_push(
613 struct xfs_log_item *lip)
614{
615 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
616 struct xfs_buf *bp = bip->bli_buf;
617
618 ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
619 ASSERT(!XFS_BUF_ISDELAYWRITE(bp));
620
621 trace_xfs_buf_item_push(bip);
622
623 xfs_buf_relse(bp);
624}
625
626/*
627 * The buffer is locked and is a delayed write buffer. Promote the buffer
628 * in the delayed write queue as the caller knows that they must invoke
629 * the xfsbufd to get this buffer written. We have to unlock the buffer
630 * to allow the xfsbufd to write it, too.
631 */
632STATIC bool
633xfs_buf_item_pushbuf(
634 struct xfs_log_item *lip)
635{
636 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
637 struct xfs_buf *bp = bip->bli_buf;
638
639 ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
640 ASSERT(XFS_BUF_ISDELAYWRITE(bp));
641
642 trace_xfs_buf_item_pushbuf(bip);
643
644 xfs_buf_delwri_promote(bp);
645 xfs_buf_relse(bp);
646 return true;
647}
648
649STATIC void
650xfs_buf_item_committing(
651 struct xfs_log_item *lip,
652 xfs_lsn_t commit_lsn)
653{
654}
655
656/*
657 * This is the ops vector shared by all buf log items.
658 */
659static struct xfs_item_ops xfs_buf_item_ops = {
660 .iop_size = xfs_buf_item_size,
661 .iop_format = xfs_buf_item_format,
662 .iop_pin = xfs_buf_item_pin,
663 .iop_unpin = xfs_buf_item_unpin,
664 .iop_trylock = xfs_buf_item_trylock,
665 .iop_unlock = xfs_buf_item_unlock,
666 .iop_committed = xfs_buf_item_committed,
667 .iop_push = xfs_buf_item_push,
668 .iop_pushbuf = xfs_buf_item_pushbuf,
669 .iop_committing = xfs_buf_item_committing
670};
671
672
673/*
674 * Allocate a new buf log item to go with the given buffer.
675 * Set the buffer's b_fsprivate field to point to the new
676 * buf log item. If there are other item's attached to the
677 * buffer (see xfs_buf_attach_iodone() below), then put the
678 * buf log item at the front.
679 */
680void
681xfs_buf_item_init(
682 xfs_buf_t *bp,
683 xfs_mount_t *mp)
684{
685 xfs_log_item_t *lip = bp->b_fspriv;
686 xfs_buf_log_item_t *bip;
687 int chunks;
688 int map_size;
689
690 /*
691 * Check to see if there is already a buf log item for
692 * this buffer. If there is, it is guaranteed to be
693 * the first. If we do already have one, there is
694 * nothing to do here so return.
695 */
696 ASSERT(bp->b_target->bt_mount == mp);
697 if (lip != NULL && lip->li_type == XFS_LI_BUF)
698 return;
699
700 /*
701 * chunks is the number of XFS_BLF_CHUNK size pieces
702 * the buffer can be divided into. Make sure not to
703 * truncate any pieces. map_size is the size of the
704 * bitmap needed to describe the chunks of the buffer.
705 */
706 chunks = (int)((XFS_BUF_COUNT(bp) + (XFS_BLF_CHUNK - 1)) >> XFS_BLF_SHIFT);
707 map_size = (int)((chunks + NBWORD) >> BIT_TO_WORD_SHIFT);
708
709 bip = (xfs_buf_log_item_t*)kmem_zone_zalloc(xfs_buf_item_zone,
710 KM_SLEEP);
711 xfs_log_item_init(mp, &bip->bli_item, XFS_LI_BUF, &xfs_buf_item_ops);
712 bip->bli_buf = bp;
713 xfs_buf_hold(bp);
714 bip->bli_format.blf_type = XFS_LI_BUF;
715 bip->bli_format.blf_blkno = (__int64_t)XFS_BUF_ADDR(bp);
716 bip->bli_format.blf_len = (ushort)BTOBB(XFS_BUF_COUNT(bp));
717 bip->bli_format.blf_map_size = map_size;
718
719#ifdef XFS_TRANS_DEBUG
720 /*
721 * Allocate the arrays for tracking what needs to be logged
722 * and what our callers request to be logged. bli_orig
723 * holds a copy of the original, clean buffer for comparison
724 * against, and bli_logged keeps a 1 bit flag per byte in
725 * the buffer to indicate which bytes the callers have asked
726 * to have logged.
727 */
728 bip->bli_orig = (char *)kmem_alloc(XFS_BUF_COUNT(bp), KM_SLEEP);
729 memcpy(bip->bli_orig, bp->b_addr, XFS_BUF_COUNT(bp));
730 bip->bli_logged = (char *)kmem_zalloc(XFS_BUF_COUNT(bp) / NBBY, KM_SLEEP);
731#endif
732
733 /*
734 * Put the buf item into the list of items attached to the
735 * buffer at the front.
736 */
737 if (bp->b_fspriv)
738 bip->bli_item.li_bio_list = bp->b_fspriv;
739 bp->b_fspriv = bip;
740}
741
742
743/*
744 * Mark bytes first through last inclusive as dirty in the buf
745 * item's bitmap.
746 */
747void
748xfs_buf_item_log(
749 xfs_buf_log_item_t *bip,
750 uint first,
751 uint last)
752{
753 uint first_bit;
754 uint last_bit;
755 uint bits_to_set;
756 uint bits_set;
757 uint word_num;
758 uint *wordp;
759 uint bit;
760 uint end_bit;
761 uint mask;
762
763 /*
764 * Mark the item as having some dirty data for
765 * quick reference in xfs_buf_item_dirty.
766 */
767 bip->bli_flags |= XFS_BLI_DIRTY;
768
769 /*
770 * Convert byte offsets to bit numbers.
771 */
772 first_bit = first >> XFS_BLF_SHIFT;
773 last_bit = last >> XFS_BLF_SHIFT;
774
775 /*
776 * Calculate the total number of bits to be set.
777 */
778 bits_to_set = last_bit - first_bit + 1;
779
780 /*
781 * Get a pointer to the first word in the bitmap
782 * to set a bit in.
783 */
784 word_num = first_bit >> BIT_TO_WORD_SHIFT;
785 wordp = &(bip->bli_format.blf_data_map[word_num]);
786
787 /*
788 * Calculate the starting bit in the first word.
789 */
790 bit = first_bit & (uint)(NBWORD - 1);
791
792 /*
793 * First set any bits in the first word of our range.
794 * If it starts at bit 0 of the word, it will be
795 * set below rather than here. That is what the variable
796 * bit tells us. The variable bits_set tracks the number
797 * of bits that have been set so far. End_bit is the number
798 * of the last bit to be set in this word plus one.
799 */
800 if (bit) {
801 end_bit = MIN(bit + bits_to_set, (uint)NBWORD);
802 mask = ((1 << (end_bit - bit)) - 1) << bit;
803 *wordp |= mask;
804 wordp++;
805 bits_set = end_bit - bit;
806 } else {
807 bits_set = 0;
808 }
809
810 /*
811 * Now set bits a whole word at a time that are between
812 * first_bit and last_bit.
813 */
814 while ((bits_to_set - bits_set) >= NBWORD) {
815 *wordp |= 0xffffffff;
816 bits_set += NBWORD;
817 wordp++;
818 }
819
820 /*
821 * Finally, set any bits left to be set in one last partial word.
822 */
823 end_bit = bits_to_set - bits_set;
824 if (end_bit) {
825 mask = (1 << end_bit) - 1;
826 *wordp |= mask;
827 }
828
829 xfs_buf_item_log_debug(bip, first, last);
830}
831
832
833/*
834 * Return 1 if the buffer has some data that has been logged (at any
835 * point, not just the current transaction) and 0 if not.
836 */
837uint
838xfs_buf_item_dirty(
839 xfs_buf_log_item_t *bip)
840{
841 return (bip->bli_flags & XFS_BLI_DIRTY);
842}
843
844STATIC void
845xfs_buf_item_free(
846 xfs_buf_log_item_t *bip)
847{
848#ifdef XFS_TRANS_DEBUG
849 kmem_free(bip->bli_orig);
850 kmem_free(bip->bli_logged);
851#endif /* XFS_TRANS_DEBUG */
852
853 kmem_zone_free(xfs_buf_item_zone, bip);
854}
855
856/*
857 * This is called when the buf log item is no longer needed. It should
858 * free the buf log item associated with the given buffer and clear
859 * the buffer's pointer to the buf log item. If there are no more
860 * items in the list, clear the b_iodone field of the buffer (see
861 * xfs_buf_attach_iodone() below).
862 */
863void
864xfs_buf_item_relse(
865 xfs_buf_t *bp)
866{
867 xfs_buf_log_item_t *bip;
868
869 trace_xfs_buf_item_relse(bp, _RET_IP_);
870
871 bip = bp->b_fspriv;
872 bp->b_fspriv = bip->bli_item.li_bio_list;
873 if (bp->b_fspriv == NULL)
874 bp->b_iodone = NULL;
875
876 xfs_buf_rele(bp);
877 xfs_buf_item_free(bip);
878}
879
880
881/*
882 * Add the given log item with its callback to the list of callbacks
883 * to be called when the buffer's I/O completes. If it is not set
884 * already, set the buffer's b_iodone() routine to be
885 * xfs_buf_iodone_callbacks() and link the log item into the list of
886 * items rooted at b_fsprivate. Items are always added as the second
887 * entry in the list if there is a first, because the buf item code
888 * assumes that the buf log item is first.
889 */
890void
891xfs_buf_attach_iodone(
892 xfs_buf_t *bp,
893 void (*cb)(xfs_buf_t *, xfs_log_item_t *),
894 xfs_log_item_t *lip)
895{
896 xfs_log_item_t *head_lip;
897
898 ASSERT(xfs_buf_islocked(bp));
899
900 lip->li_cb = cb;
901 head_lip = bp->b_fspriv;
902 if (head_lip) {
903 lip->li_bio_list = head_lip->li_bio_list;
904 head_lip->li_bio_list = lip;
905 } else {
906 bp->b_fspriv = lip;
907 }
908
909 ASSERT(bp->b_iodone == NULL ||
910 bp->b_iodone == xfs_buf_iodone_callbacks);
911 bp->b_iodone = xfs_buf_iodone_callbacks;
912}
913
914/*
915 * We can have many callbacks on a buffer. Running the callbacks individually
916 * can cause a lot of contention on the AIL lock, so we allow for a single
917 * callback to be able to scan the remaining lip->li_bio_list for other items
918 * of the same type and callback to be processed in the first call.
919 *
920 * As a result, the loop walking the callback list below will also modify the
921 * list. it removes the first item from the list and then runs the callback.
922 * The loop then restarts from the new head of the list. This allows the
923 * callback to scan and modify the list attached to the buffer and we don't
924 * have to care about maintaining a next item pointer.
925 */
926STATIC void
927xfs_buf_do_callbacks(
928 struct xfs_buf *bp)
929{
930 struct xfs_log_item *lip;
931
932 while ((lip = bp->b_fspriv) != NULL) {
933 bp->b_fspriv = lip->li_bio_list;
934 ASSERT(lip->li_cb != NULL);
935 /*
936 * Clear the next pointer so we don't have any
937 * confusion if the item is added to another buf.
938 * Don't touch the log item after calling its
939 * callback, because it could have freed itself.
940 */
941 lip->li_bio_list = NULL;
942 lip->li_cb(bp, lip);
943 }
944}
945
946/*
947 * This is the iodone() function for buffers which have had callbacks
948 * attached to them by xfs_buf_attach_iodone(). It should remove each
949 * log item from the buffer's list and call the callback of each in turn.
950 * When done, the buffer's fsprivate field is set to NULL and the buffer
951 * is unlocked with a call to iodone().
952 */
953void
954xfs_buf_iodone_callbacks(
955 struct xfs_buf *bp)
956{
957 struct xfs_log_item *lip = bp->b_fspriv;
958 struct xfs_mount *mp = lip->li_mountp;
959 static ulong lasttime;
960 static xfs_buftarg_t *lasttarg;
961
962 if (likely(!xfs_buf_geterror(bp)))
963 goto do_callbacks;
964
965 /*
966 * If we've already decided to shutdown the filesystem because of
967 * I/O errors, there's no point in giving this a retry.
968 */
969 if (XFS_FORCED_SHUTDOWN(mp)) {
970 XFS_BUF_SUPER_STALE(bp);
971 trace_xfs_buf_item_iodone(bp, _RET_IP_);
972 goto do_callbacks;
973 }
974
975 if (bp->b_target != lasttarg ||
976 time_after(jiffies, (lasttime + 5*HZ))) {
977 lasttime = jiffies;
978 xfs_alert(mp, "Device %s: metadata write error block 0x%llx",
979 xfs_buf_target_name(bp->b_target),
980 (__uint64_t)XFS_BUF_ADDR(bp));
981 }
982 lasttarg = bp->b_target;
983
984 /*
985 * If the write was asynchronous then no one will be looking for the
986 * error. Clear the error state and write the buffer out again.
987 *
988 * During sync or umount we'll write all pending buffers again
989 * synchronous, which will catch these errors if they keep hanging
990 * around.
991 */
992 if (XFS_BUF_ISASYNC(bp)) {
993 xfs_buf_ioerror(bp, 0); /* errno of 0 unsets the flag */
994
995 if (!XFS_BUF_ISSTALE(bp)) {
996 XFS_BUF_DELAYWRITE(bp);
997 XFS_BUF_DONE(bp);
998 }
999 ASSERT(bp->b_iodone != NULL);
1000 trace_xfs_buf_item_iodone_async(bp, _RET_IP_);
1001 xfs_buf_relse(bp);
1002 return;
1003 }
1004
1005 /*
1006 * If the write of the buffer was synchronous, we want to make
1007 * sure to return the error to the caller of xfs_bwrite().
1008 */
1009 XFS_BUF_STALE(bp);
1010 XFS_BUF_DONE(bp);
1011 XFS_BUF_UNDELAYWRITE(bp);
1012
1013 trace_xfs_buf_error_relse(bp, _RET_IP_);
1014
1015do_callbacks:
1016 xfs_buf_do_callbacks(bp);
1017 bp->b_fspriv = NULL;
1018 bp->b_iodone = NULL;
1019 xfs_buf_ioend(bp, 0);
1020}
1021
1022/*
1023 * This is the iodone() function for buffers which have been
1024 * logged. It is called when they are eventually flushed out.
1025 * It should remove the buf item from the AIL, and free the buf item.
1026 * It is called by xfs_buf_iodone_callbacks() above which will take
1027 * care of cleaning up the buffer itself.
1028 */
1029void
1030xfs_buf_iodone(
1031 struct xfs_buf *bp,
1032 struct xfs_log_item *lip)
1033{
1034 struct xfs_ail *ailp = lip->li_ailp;
1035
1036 ASSERT(BUF_ITEM(lip)->bli_buf == bp);
1037
1038 xfs_buf_rele(bp);
1039
1040 /*
1041 * If we are forcibly shutting down, this may well be
1042 * off the AIL already. That's because we simulate the
1043 * log-committed callbacks to unpin these buffers. Or we may never
1044 * have put this item on AIL because of the transaction was
1045 * aborted forcibly. xfs_trans_ail_delete() takes care of these.
1046 *
1047 * Either way, AIL is useless if we're forcing a shutdown.
1048 */
1049 spin_lock(&ailp->xa_lock);
1050 xfs_trans_ail_delete(ailp, lip);
1051 xfs_buf_item_free(BUF_ITEM(lip));
1052}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_log_format.h"
11#include "xfs_trans_resv.h"
12#include "xfs_bit.h"
13#include "xfs_mount.h"
14#include "xfs_trans.h"
15#include "xfs_trans_priv.h"
16#include "xfs_buf_item.h"
17#include "xfs_inode.h"
18#include "xfs_inode_item.h"
19#include "xfs_quota.h"
20#include "xfs_dquot_item.h"
21#include "xfs_dquot.h"
22#include "xfs_trace.h"
23#include "xfs_log.h"
24#include "xfs_log_priv.h"
25
26
27struct kmem_cache *xfs_buf_item_cache;
28
29static inline struct xfs_buf_log_item *BUF_ITEM(struct xfs_log_item *lip)
30{
31 return container_of(lip, struct xfs_buf_log_item, bli_item);
32}
33
34/* Is this log iovec plausibly large enough to contain the buffer log format? */
35bool
36xfs_buf_log_check_iovec(
37 struct xfs_log_iovec *iovec)
38{
39 struct xfs_buf_log_format *blfp = iovec->i_addr;
40 char *bmp_end;
41 char *item_end;
42
43 if (offsetof(struct xfs_buf_log_format, blf_data_map) > iovec->i_len)
44 return false;
45
46 item_end = (char *)iovec->i_addr + iovec->i_len;
47 bmp_end = (char *)&blfp->blf_data_map[blfp->blf_map_size];
48 return bmp_end <= item_end;
49}
50
51static inline int
52xfs_buf_log_format_size(
53 struct xfs_buf_log_format *blfp)
54{
55 return offsetof(struct xfs_buf_log_format, blf_data_map) +
56 (blfp->blf_map_size * sizeof(blfp->blf_data_map[0]));
57}
58
59static inline bool
60xfs_buf_item_straddle(
61 struct xfs_buf *bp,
62 uint offset,
63 int first_bit,
64 int nbits)
65{
66 void *first, *last;
67
68 first = xfs_buf_offset(bp, offset + (first_bit << XFS_BLF_SHIFT));
69 last = xfs_buf_offset(bp,
70 offset + ((first_bit + nbits) << XFS_BLF_SHIFT));
71
72 if (last - first != nbits * XFS_BLF_CHUNK)
73 return true;
74 return false;
75}
76
77/*
78 * Return the number of log iovecs and space needed to log the given buf log
79 * item segment.
80 *
81 * It calculates this as 1 iovec for the buf log format structure and 1 for each
82 * stretch of non-contiguous chunks to be logged. Contiguous chunks are logged
83 * in a single iovec.
84 */
85STATIC void
86xfs_buf_item_size_segment(
87 struct xfs_buf_log_item *bip,
88 struct xfs_buf_log_format *blfp,
89 uint offset,
90 int *nvecs,
91 int *nbytes)
92{
93 struct xfs_buf *bp = bip->bli_buf;
94 int first_bit;
95 int nbits;
96 int next_bit;
97 int last_bit;
98
99 first_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, 0);
100 if (first_bit == -1)
101 return;
102
103 (*nvecs)++;
104 *nbytes += xfs_buf_log_format_size(blfp);
105
106 do {
107 nbits = xfs_contig_bits(blfp->blf_data_map,
108 blfp->blf_map_size, first_bit);
109 ASSERT(nbits > 0);
110
111 /*
112 * Straddling a page is rare because we don't log contiguous
113 * chunks of unmapped buffers anywhere.
114 */
115 if (nbits > 1 &&
116 xfs_buf_item_straddle(bp, offset, first_bit, nbits))
117 goto slow_scan;
118
119 (*nvecs)++;
120 *nbytes += nbits * XFS_BLF_CHUNK;
121
122 /*
123 * This takes the bit number to start looking from and
124 * returns the next set bit from there. It returns -1
125 * if there are no more bits set or the start bit is
126 * beyond the end of the bitmap.
127 */
128 first_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size,
129 (uint)first_bit + nbits + 1);
130 } while (first_bit != -1);
131
132 return;
133
134slow_scan:
135 /* Count the first bit we jumped out of the above loop from */
136 (*nvecs)++;
137 *nbytes += XFS_BLF_CHUNK;
138 last_bit = first_bit;
139 while (last_bit != -1) {
140 /*
141 * This takes the bit number to start looking from and
142 * returns the next set bit from there. It returns -1
143 * if there are no more bits set or the start bit is
144 * beyond the end of the bitmap.
145 */
146 next_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size,
147 last_bit + 1);
148 /*
149 * If we run out of bits, leave the loop,
150 * else if we find a new set of bits bump the number of vecs,
151 * else keep scanning the current set of bits.
152 */
153 if (next_bit == -1) {
154 break;
155 } else if (next_bit != last_bit + 1 ||
156 xfs_buf_item_straddle(bp, offset, first_bit, nbits)) {
157 last_bit = next_bit;
158 first_bit = next_bit;
159 (*nvecs)++;
160 nbits = 1;
161 } else {
162 last_bit++;
163 nbits++;
164 }
165 *nbytes += XFS_BLF_CHUNK;
166 }
167}
168
169/*
170 * Return the number of log iovecs and space needed to log the given buf log
171 * item.
172 *
173 * Discontiguous buffers need a format structure per region that is being
174 * logged. This makes the changes in the buffer appear to log recovery as though
175 * they came from separate buffers, just like would occur if multiple buffers
176 * were used instead of a single discontiguous buffer. This enables
177 * discontiguous buffers to be in-memory constructs, completely transparent to
178 * what ends up on disk.
179 *
180 * If the XFS_BLI_STALE flag has been set, then log nothing but the buf log
181 * format structures. If the item has previously been logged and has dirty
182 * regions, we do not relog them in stale buffers. This has the effect of
183 * reducing the size of the relogged item by the amount of dirty data tracked
184 * by the log item. This can result in the committing transaction reducing the
185 * amount of space being consumed by the CIL.
186 */
187STATIC void
188xfs_buf_item_size(
189 struct xfs_log_item *lip,
190 int *nvecs,
191 int *nbytes)
192{
193 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
194 struct xfs_buf *bp = bip->bli_buf;
195 int i;
196 int bytes;
197 uint offset = 0;
198
199 ASSERT(atomic_read(&bip->bli_refcount) > 0);
200 if (bip->bli_flags & XFS_BLI_STALE) {
201 /*
202 * The buffer is stale, so all we need to log is the buf log
203 * format structure with the cancel flag in it as we are never
204 * going to replay the changes tracked in the log item.
205 */
206 trace_xfs_buf_item_size_stale(bip);
207 ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
208 *nvecs += bip->bli_format_count;
209 for (i = 0; i < bip->bli_format_count; i++) {
210 *nbytes += xfs_buf_log_format_size(&bip->bli_formats[i]);
211 }
212 return;
213 }
214
215 ASSERT(bip->bli_flags & XFS_BLI_LOGGED);
216
217 if (bip->bli_flags & XFS_BLI_ORDERED) {
218 /*
219 * The buffer has been logged just to order it. It is not being
220 * included in the transaction commit, so no vectors are used at
221 * all.
222 */
223 trace_xfs_buf_item_size_ordered(bip);
224 *nvecs = XFS_LOG_VEC_ORDERED;
225 return;
226 }
227
228 /*
229 * The vector count is based on the number of buffer vectors we have
230 * dirty bits in. This will only be greater than one when we have a
231 * compound buffer with more than one segment dirty. Hence for compound
232 * buffers we need to track which segment the dirty bits correspond to,
233 * and when we move from one segment to the next increment the vector
234 * count for the extra buf log format structure that will need to be
235 * written.
236 */
237 bytes = 0;
238 for (i = 0; i < bip->bli_format_count; i++) {
239 xfs_buf_item_size_segment(bip, &bip->bli_formats[i], offset,
240 nvecs, &bytes);
241 offset += BBTOB(bp->b_maps[i].bm_len);
242 }
243
244 /*
245 * Round up the buffer size required to minimise the number of memory
246 * allocations that need to be done as this item grows when relogged by
247 * repeated modifications.
248 */
249 *nbytes = round_up(bytes, 512);
250 trace_xfs_buf_item_size(bip);
251}
252
253static inline void
254xfs_buf_item_copy_iovec(
255 struct xfs_log_vec *lv,
256 struct xfs_log_iovec **vecp,
257 struct xfs_buf *bp,
258 uint offset,
259 int first_bit,
260 uint nbits)
261{
262 offset += first_bit * XFS_BLF_CHUNK;
263 xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_BCHUNK,
264 xfs_buf_offset(bp, offset),
265 nbits * XFS_BLF_CHUNK);
266}
267
268static void
269xfs_buf_item_format_segment(
270 struct xfs_buf_log_item *bip,
271 struct xfs_log_vec *lv,
272 struct xfs_log_iovec **vecp,
273 uint offset,
274 struct xfs_buf_log_format *blfp)
275{
276 struct xfs_buf *bp = bip->bli_buf;
277 uint base_size;
278 int first_bit;
279 int last_bit;
280 int next_bit;
281 uint nbits;
282
283 /* copy the flags across from the base format item */
284 blfp->blf_flags = bip->__bli_format.blf_flags;
285
286 /*
287 * Base size is the actual size of the ondisk structure - it reflects
288 * the actual size of the dirty bitmap rather than the size of the in
289 * memory structure.
290 */
291 base_size = xfs_buf_log_format_size(blfp);
292
293 first_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size, 0);
294 if (!(bip->bli_flags & XFS_BLI_STALE) && first_bit == -1) {
295 /*
296 * If the map is not be dirty in the transaction, mark
297 * the size as zero and do not advance the vector pointer.
298 */
299 return;
300 }
301
302 blfp = xlog_copy_iovec(lv, vecp, XLOG_REG_TYPE_BFORMAT, blfp, base_size);
303 blfp->blf_size = 1;
304
305 if (bip->bli_flags & XFS_BLI_STALE) {
306 /*
307 * The buffer is stale, so all we need to log
308 * is the buf log format structure with the
309 * cancel flag in it.
310 */
311 trace_xfs_buf_item_format_stale(bip);
312 ASSERT(blfp->blf_flags & XFS_BLF_CANCEL);
313 return;
314 }
315
316
317 /*
318 * Fill in an iovec for each set of contiguous chunks.
319 */
320 do {
321 ASSERT(first_bit >= 0);
322 nbits = xfs_contig_bits(blfp->blf_data_map,
323 blfp->blf_map_size, first_bit);
324 ASSERT(nbits > 0);
325
326 /*
327 * Straddling a page is rare because we don't log contiguous
328 * chunks of unmapped buffers anywhere.
329 */
330 if (nbits > 1 &&
331 xfs_buf_item_straddle(bp, offset, first_bit, nbits))
332 goto slow_scan;
333
334 xfs_buf_item_copy_iovec(lv, vecp, bp, offset,
335 first_bit, nbits);
336 blfp->blf_size++;
337
338 /*
339 * This takes the bit number to start looking from and
340 * returns the next set bit from there. It returns -1
341 * if there are no more bits set or the start bit is
342 * beyond the end of the bitmap.
343 */
344 first_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size,
345 (uint)first_bit + nbits + 1);
346 } while (first_bit != -1);
347
348 return;
349
350slow_scan:
351 ASSERT(bp->b_addr == NULL);
352 last_bit = first_bit;
353 nbits = 1;
354 for (;;) {
355 /*
356 * This takes the bit number to start looking from and
357 * returns the next set bit from there. It returns -1
358 * if there are no more bits set or the start bit is
359 * beyond the end of the bitmap.
360 */
361 next_bit = xfs_next_bit(blfp->blf_data_map, blfp->blf_map_size,
362 (uint)last_bit + 1);
363 /*
364 * If we run out of bits fill in the last iovec and get out of
365 * the loop. Else if we start a new set of bits then fill in
366 * the iovec for the series we were looking at and start
367 * counting the bits in the new one. Else we're still in the
368 * same set of bits so just keep counting and scanning.
369 */
370 if (next_bit == -1) {
371 xfs_buf_item_copy_iovec(lv, vecp, bp, offset,
372 first_bit, nbits);
373 blfp->blf_size++;
374 break;
375 } else if (next_bit != last_bit + 1 ||
376 xfs_buf_item_straddle(bp, offset, first_bit, nbits)) {
377 xfs_buf_item_copy_iovec(lv, vecp, bp, offset,
378 first_bit, nbits);
379 blfp->blf_size++;
380 first_bit = next_bit;
381 last_bit = next_bit;
382 nbits = 1;
383 } else {
384 last_bit++;
385 nbits++;
386 }
387 }
388}
389
390/*
391 * This is called to fill in the vector of log iovecs for the
392 * given log buf item. It fills the first entry with a buf log
393 * format structure, and the rest point to contiguous chunks
394 * within the buffer.
395 */
396STATIC void
397xfs_buf_item_format(
398 struct xfs_log_item *lip,
399 struct xfs_log_vec *lv)
400{
401 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
402 struct xfs_buf *bp = bip->bli_buf;
403 struct xfs_log_iovec *vecp = NULL;
404 uint offset = 0;
405 int i;
406
407 ASSERT(atomic_read(&bip->bli_refcount) > 0);
408 ASSERT((bip->bli_flags & XFS_BLI_LOGGED) ||
409 (bip->bli_flags & XFS_BLI_STALE));
410 ASSERT((bip->bli_flags & XFS_BLI_STALE) ||
411 (xfs_blft_from_flags(&bip->__bli_format) > XFS_BLFT_UNKNOWN_BUF
412 && xfs_blft_from_flags(&bip->__bli_format) < XFS_BLFT_MAX_BUF));
413 ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED) ||
414 (bip->bli_flags & XFS_BLI_STALE));
415
416
417 /*
418 * If it is an inode buffer, transfer the in-memory state to the
419 * format flags and clear the in-memory state.
420 *
421 * For buffer based inode allocation, we do not transfer
422 * this state if the inode buffer allocation has not yet been committed
423 * to the log as setting the XFS_BLI_INODE_BUF flag will prevent
424 * correct replay of the inode allocation.
425 *
426 * For icreate item based inode allocation, the buffers aren't written
427 * to the journal during allocation, and hence we should always tag the
428 * buffer as an inode buffer so that the correct unlinked list replay
429 * occurs during recovery.
430 */
431 if (bip->bli_flags & XFS_BLI_INODE_BUF) {
432 if (xfs_has_v3inodes(lip->li_log->l_mp) ||
433 !((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) &&
434 xfs_log_item_in_current_chkpt(lip)))
435 bip->__bli_format.blf_flags |= XFS_BLF_INODE_BUF;
436 bip->bli_flags &= ~XFS_BLI_INODE_BUF;
437 }
438
439 for (i = 0; i < bip->bli_format_count; i++) {
440 xfs_buf_item_format_segment(bip, lv, &vecp, offset,
441 &bip->bli_formats[i]);
442 offset += BBTOB(bp->b_maps[i].bm_len);
443 }
444
445 /*
446 * Check to make sure everything is consistent.
447 */
448 trace_xfs_buf_item_format(bip);
449}
450
451/*
452 * This is called to pin the buffer associated with the buf log item in memory
453 * so it cannot be written out.
454 *
455 * We take a reference to the buffer log item here so that the BLI life cycle
456 * extends at least until the buffer is unpinned via xfs_buf_item_unpin() and
457 * inserted into the AIL.
458 *
459 * We also need to take a reference to the buffer itself as the BLI unpin
460 * processing requires accessing the buffer after the BLI has dropped the final
461 * BLI reference. See xfs_buf_item_unpin() for an explanation.
462 * If unpins race to drop the final BLI reference and only the
463 * BLI owns a reference to the buffer, then the loser of the race can have the
464 * buffer fgreed from under it (e.g. on shutdown). Taking a buffer reference per
465 * pin count ensures the life cycle of the buffer extends for as
466 * long as we hold the buffer pin reference in xfs_buf_item_unpin().
467 */
468STATIC void
469xfs_buf_item_pin(
470 struct xfs_log_item *lip)
471{
472 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
473
474 ASSERT(atomic_read(&bip->bli_refcount) > 0);
475 ASSERT((bip->bli_flags & XFS_BLI_LOGGED) ||
476 (bip->bli_flags & XFS_BLI_ORDERED) ||
477 (bip->bli_flags & XFS_BLI_STALE));
478
479 trace_xfs_buf_item_pin(bip);
480
481 xfs_buf_hold(bip->bli_buf);
482 atomic_inc(&bip->bli_refcount);
483 atomic_inc(&bip->bli_buf->b_pin_count);
484}
485
486/*
487 * This is called to unpin the buffer associated with the buf log item which was
488 * previously pinned with a call to xfs_buf_item_pin(). We enter this function
489 * with a buffer pin count, a buffer reference and a BLI reference.
490 *
491 * We must drop the BLI reference before we unpin the buffer because the AIL
492 * doesn't acquire a BLI reference whenever it accesses it. Therefore if the
493 * refcount drops to zero, the bli could still be AIL resident and the buffer
494 * submitted for I/O at any point before we return. This can result in IO
495 * completion freeing the buffer while we are still trying to access it here.
496 * This race condition can also occur in shutdown situations where we abort and
497 * unpin buffers from contexts other that journal IO completion.
498 *
499 * Hence we have to hold a buffer reference per pin count to ensure that the
500 * buffer cannot be freed until we have finished processing the unpin operation.
501 * The reference is taken in xfs_buf_item_pin(), and we must hold it until we
502 * are done processing the buffer state. In the case of an abort (remove =
503 * true) then we re-use the current pin reference as the IO reference we hand
504 * off to IO failure handling.
505 */
506STATIC void
507xfs_buf_item_unpin(
508 struct xfs_log_item *lip,
509 int remove)
510{
511 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
512 struct xfs_buf *bp = bip->bli_buf;
513 int stale = bip->bli_flags & XFS_BLI_STALE;
514 int freed;
515
516 ASSERT(bp->b_log_item == bip);
517 ASSERT(atomic_read(&bip->bli_refcount) > 0);
518
519 trace_xfs_buf_item_unpin(bip);
520
521 freed = atomic_dec_and_test(&bip->bli_refcount);
522 if (atomic_dec_and_test(&bp->b_pin_count))
523 wake_up_all(&bp->b_waiters);
524
525 /*
526 * Nothing to do but drop the buffer pin reference if the BLI is
527 * still active.
528 */
529 if (!freed) {
530 xfs_buf_rele(bp);
531 return;
532 }
533
534 if (stale) {
535 ASSERT(bip->bli_flags & XFS_BLI_STALE);
536 ASSERT(xfs_buf_islocked(bp));
537 ASSERT(bp->b_flags & XBF_STALE);
538 ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
539 ASSERT(list_empty(&lip->li_trans));
540 ASSERT(!bp->b_transp);
541
542 trace_xfs_buf_item_unpin_stale(bip);
543
544 /*
545 * The buffer has been locked and referenced since it was marked
546 * stale so we own both lock and reference exclusively here. We
547 * do not need the pin reference any more, so drop it now so
548 * that we only have one reference to drop once item completion
549 * processing is complete.
550 */
551 xfs_buf_rele(bp);
552
553 /*
554 * If we get called here because of an IO error, we may or may
555 * not have the item on the AIL. xfs_trans_ail_delete() will
556 * take care of that situation. xfs_trans_ail_delete() drops
557 * the AIL lock.
558 */
559 if (bip->bli_flags & XFS_BLI_STALE_INODE) {
560 xfs_buf_item_done(bp);
561 xfs_buf_inode_iodone(bp);
562 ASSERT(list_empty(&bp->b_li_list));
563 } else {
564 xfs_trans_ail_delete(lip, SHUTDOWN_LOG_IO_ERROR);
565 xfs_buf_item_relse(bp);
566 ASSERT(bp->b_log_item == NULL);
567 }
568 xfs_buf_relse(bp);
569 return;
570 }
571
572 if (remove) {
573 /*
574 * We need to simulate an async IO failures here to ensure that
575 * the correct error completion is run on this buffer. This
576 * requires a reference to the buffer and for the buffer to be
577 * locked. We can safely pass ownership of the pin reference to
578 * the IO to ensure that nothing can free the buffer while we
579 * wait for the lock and then run the IO failure completion.
580 */
581 xfs_buf_lock(bp);
582 bp->b_flags |= XBF_ASYNC;
583 xfs_buf_ioend_fail(bp);
584 return;
585 }
586
587 /*
588 * BLI has no more active references - it will be moved to the AIL to
589 * manage the remaining BLI/buffer life cycle. There is nothing left for
590 * us to do here so drop the pin reference to the buffer.
591 */
592 xfs_buf_rele(bp);
593}
594
595STATIC uint
596xfs_buf_item_push(
597 struct xfs_log_item *lip,
598 struct list_head *buffer_list)
599{
600 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
601 struct xfs_buf *bp = bip->bli_buf;
602 uint rval = XFS_ITEM_SUCCESS;
603
604 if (xfs_buf_ispinned(bp))
605 return XFS_ITEM_PINNED;
606 if (!xfs_buf_trylock(bp)) {
607 /*
608 * If we have just raced with a buffer being pinned and it has
609 * been marked stale, we could end up stalling until someone else
610 * issues a log force to unpin the stale buffer. Check for the
611 * race condition here so xfsaild recognizes the buffer is pinned
612 * and queues a log force to move it along.
613 */
614 if (xfs_buf_ispinned(bp))
615 return XFS_ITEM_PINNED;
616 return XFS_ITEM_LOCKED;
617 }
618
619 ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
620
621 trace_xfs_buf_item_push(bip);
622
623 /* has a previous flush failed due to IO errors? */
624 if (bp->b_flags & XBF_WRITE_FAIL) {
625 xfs_buf_alert_ratelimited(bp, "XFS: Failing async write",
626 "Failing async write on buffer block 0x%llx. Retrying async write.",
627 (long long)xfs_buf_daddr(bp));
628 }
629
630 if (!xfs_buf_delwri_queue(bp, buffer_list))
631 rval = XFS_ITEM_FLUSHING;
632 xfs_buf_unlock(bp);
633 return rval;
634}
635
636/*
637 * Drop the buffer log item refcount and take appropriate action. This helper
638 * determines whether the bli must be freed or not, since a decrement to zero
639 * does not necessarily mean the bli is unused.
640 *
641 * Return true if the bli is freed, false otherwise.
642 */
643bool
644xfs_buf_item_put(
645 struct xfs_buf_log_item *bip)
646{
647 struct xfs_log_item *lip = &bip->bli_item;
648 bool aborted;
649 bool dirty;
650
651 /* drop the bli ref and return if it wasn't the last one */
652 if (!atomic_dec_and_test(&bip->bli_refcount))
653 return false;
654
655 /*
656 * We dropped the last ref and must free the item if clean or aborted.
657 * If the bli is dirty and non-aborted, the buffer was clean in the
658 * transaction but still awaiting writeback from previous changes. In
659 * that case, the bli is freed on buffer writeback completion.
660 */
661 aborted = test_bit(XFS_LI_ABORTED, &lip->li_flags) ||
662 xlog_is_shutdown(lip->li_log);
663 dirty = bip->bli_flags & XFS_BLI_DIRTY;
664 if (dirty && !aborted)
665 return false;
666
667 /*
668 * The bli is aborted or clean. An aborted item may be in the AIL
669 * regardless of dirty state. For example, consider an aborted
670 * transaction that invalidated a dirty bli and cleared the dirty
671 * state.
672 */
673 if (aborted)
674 xfs_trans_ail_delete(lip, 0);
675 xfs_buf_item_relse(bip->bli_buf);
676 return true;
677}
678
679/*
680 * Release the buffer associated with the buf log item. If there is no dirty
681 * logged data associated with the buffer recorded in the buf log item, then
682 * free the buf log item and remove the reference to it in the buffer.
683 *
684 * This call ignores the recursion count. It is only called when the buffer
685 * should REALLY be unlocked, regardless of the recursion count.
686 *
687 * We unconditionally drop the transaction's reference to the log item. If the
688 * item was logged, then another reference was taken when it was pinned, so we
689 * can safely drop the transaction reference now. This also allows us to avoid
690 * potential races with the unpin code freeing the bli by not referencing the
691 * bli after we've dropped the reference count.
692 *
693 * If the XFS_BLI_HOLD flag is set in the buf log item, then free the log item
694 * if necessary but do not unlock the buffer. This is for support of
695 * xfs_trans_bhold(). Make sure the XFS_BLI_HOLD field is cleared if we don't
696 * free the item.
697 */
698STATIC void
699xfs_buf_item_release(
700 struct xfs_log_item *lip)
701{
702 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
703 struct xfs_buf *bp = bip->bli_buf;
704 bool released;
705 bool hold = bip->bli_flags & XFS_BLI_HOLD;
706 bool stale = bip->bli_flags & XFS_BLI_STALE;
707#if defined(DEBUG) || defined(XFS_WARN)
708 bool ordered = bip->bli_flags & XFS_BLI_ORDERED;
709 bool dirty = bip->bli_flags & XFS_BLI_DIRTY;
710 bool aborted = test_bit(XFS_LI_ABORTED,
711 &lip->li_flags);
712#endif
713
714 trace_xfs_buf_item_release(bip);
715
716 /*
717 * The bli dirty state should match whether the blf has logged segments
718 * except for ordered buffers, where only the bli should be dirty.
719 */
720 ASSERT((!ordered && dirty == xfs_buf_item_dirty_format(bip)) ||
721 (ordered && dirty && !xfs_buf_item_dirty_format(bip)));
722 ASSERT(!stale || (bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
723
724 /*
725 * Clear the buffer's association with this transaction and
726 * per-transaction state from the bli, which has been copied above.
727 */
728 bp->b_transp = NULL;
729 bip->bli_flags &= ~(XFS_BLI_LOGGED | XFS_BLI_HOLD | XFS_BLI_ORDERED);
730
731 /*
732 * Unref the item and unlock the buffer unless held or stale. Stale
733 * buffers remain locked until final unpin unless the bli is freed by
734 * the unref call. The latter implies shutdown because buffer
735 * invalidation dirties the bli and transaction.
736 */
737 released = xfs_buf_item_put(bip);
738 if (hold || (stale && !released))
739 return;
740 ASSERT(!stale || aborted);
741 xfs_buf_relse(bp);
742}
743
744STATIC void
745xfs_buf_item_committing(
746 struct xfs_log_item *lip,
747 xfs_csn_t seq)
748{
749 return xfs_buf_item_release(lip);
750}
751
752/*
753 * This is called to find out where the oldest active copy of the
754 * buf log item in the on disk log resides now that the last log
755 * write of it completed at the given lsn.
756 * We always re-log all the dirty data in a buffer, so usually the
757 * latest copy in the on disk log is the only one that matters. For
758 * those cases we simply return the given lsn.
759 *
760 * The one exception to this is for buffers full of newly allocated
761 * inodes. These buffers are only relogged with the XFS_BLI_INODE_BUF
762 * flag set, indicating that only the di_next_unlinked fields from the
763 * inodes in the buffers will be replayed during recovery. If the
764 * original newly allocated inode images have not yet been flushed
765 * when the buffer is so relogged, then we need to make sure that we
766 * keep the old images in the 'active' portion of the log. We do this
767 * by returning the original lsn of that transaction here rather than
768 * the current one.
769 */
770STATIC xfs_lsn_t
771xfs_buf_item_committed(
772 struct xfs_log_item *lip,
773 xfs_lsn_t lsn)
774{
775 struct xfs_buf_log_item *bip = BUF_ITEM(lip);
776
777 trace_xfs_buf_item_committed(bip);
778
779 if ((bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF) && lip->li_lsn != 0)
780 return lip->li_lsn;
781 return lsn;
782}
783
784static const struct xfs_item_ops xfs_buf_item_ops = {
785 .iop_size = xfs_buf_item_size,
786 .iop_format = xfs_buf_item_format,
787 .iop_pin = xfs_buf_item_pin,
788 .iop_unpin = xfs_buf_item_unpin,
789 .iop_release = xfs_buf_item_release,
790 .iop_committing = xfs_buf_item_committing,
791 .iop_committed = xfs_buf_item_committed,
792 .iop_push = xfs_buf_item_push,
793};
794
795STATIC void
796xfs_buf_item_get_format(
797 struct xfs_buf_log_item *bip,
798 int count)
799{
800 ASSERT(bip->bli_formats == NULL);
801 bip->bli_format_count = count;
802
803 if (count == 1) {
804 bip->bli_formats = &bip->__bli_format;
805 return;
806 }
807
808 bip->bli_formats = kzalloc(count * sizeof(struct xfs_buf_log_format),
809 GFP_KERNEL | __GFP_NOFAIL);
810}
811
812STATIC void
813xfs_buf_item_free_format(
814 struct xfs_buf_log_item *bip)
815{
816 if (bip->bli_formats != &bip->__bli_format) {
817 kfree(bip->bli_formats);
818 bip->bli_formats = NULL;
819 }
820}
821
822/*
823 * Allocate a new buf log item to go with the given buffer.
824 * Set the buffer's b_log_item field to point to the new
825 * buf log item.
826 */
827int
828xfs_buf_item_init(
829 struct xfs_buf *bp,
830 struct xfs_mount *mp)
831{
832 struct xfs_buf_log_item *bip = bp->b_log_item;
833 int chunks;
834 int map_size;
835 int i;
836
837 /*
838 * Check to see if there is already a buf log item for
839 * this buffer. If we do already have one, there is
840 * nothing to do here so return.
841 */
842 ASSERT(bp->b_mount == mp);
843 if (bip) {
844 ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
845 ASSERT(!bp->b_transp);
846 ASSERT(bip->bli_buf == bp);
847 return 0;
848 }
849
850 bip = kmem_cache_zalloc(xfs_buf_item_cache, GFP_KERNEL | __GFP_NOFAIL);
851 xfs_log_item_init(mp, &bip->bli_item, XFS_LI_BUF, &xfs_buf_item_ops);
852 bip->bli_buf = bp;
853
854 /*
855 * chunks is the number of XFS_BLF_CHUNK size pieces the buffer
856 * can be divided into. Make sure not to truncate any pieces.
857 * map_size is the size of the bitmap needed to describe the
858 * chunks of the buffer.
859 *
860 * Discontiguous buffer support follows the layout of the underlying
861 * buffer. This makes the implementation as simple as possible.
862 */
863 xfs_buf_item_get_format(bip, bp->b_map_count);
864
865 for (i = 0; i < bip->bli_format_count; i++) {
866 chunks = DIV_ROUND_UP(BBTOB(bp->b_maps[i].bm_len),
867 XFS_BLF_CHUNK);
868 map_size = DIV_ROUND_UP(chunks, NBWORD);
869
870 if (map_size > XFS_BLF_DATAMAP_SIZE) {
871 kmem_cache_free(xfs_buf_item_cache, bip);
872 xfs_err(mp,
873 "buffer item dirty bitmap (%u uints) too small to reflect %u bytes!",
874 map_size,
875 BBTOB(bp->b_maps[i].bm_len));
876 return -EFSCORRUPTED;
877 }
878
879 bip->bli_formats[i].blf_type = XFS_LI_BUF;
880 bip->bli_formats[i].blf_blkno = bp->b_maps[i].bm_bn;
881 bip->bli_formats[i].blf_len = bp->b_maps[i].bm_len;
882 bip->bli_formats[i].blf_map_size = map_size;
883 }
884
885 bp->b_log_item = bip;
886 xfs_buf_hold(bp);
887 return 0;
888}
889
890
891/*
892 * Mark bytes first through last inclusive as dirty in the buf
893 * item's bitmap.
894 */
895static void
896xfs_buf_item_log_segment(
897 uint first,
898 uint last,
899 uint *map)
900{
901 uint first_bit;
902 uint last_bit;
903 uint bits_to_set;
904 uint bits_set;
905 uint word_num;
906 uint *wordp;
907 uint bit;
908 uint end_bit;
909 uint mask;
910
911 ASSERT(first < XFS_BLF_DATAMAP_SIZE * XFS_BLF_CHUNK * NBWORD);
912 ASSERT(last < XFS_BLF_DATAMAP_SIZE * XFS_BLF_CHUNK * NBWORD);
913
914 /*
915 * Convert byte offsets to bit numbers.
916 */
917 first_bit = first >> XFS_BLF_SHIFT;
918 last_bit = last >> XFS_BLF_SHIFT;
919
920 /*
921 * Calculate the total number of bits to be set.
922 */
923 bits_to_set = last_bit - first_bit + 1;
924
925 /*
926 * Get a pointer to the first word in the bitmap
927 * to set a bit in.
928 */
929 word_num = first_bit >> BIT_TO_WORD_SHIFT;
930 wordp = &map[word_num];
931
932 /*
933 * Calculate the starting bit in the first word.
934 */
935 bit = first_bit & (uint)(NBWORD - 1);
936
937 /*
938 * First set any bits in the first word of our range.
939 * If it starts at bit 0 of the word, it will be
940 * set below rather than here. That is what the variable
941 * bit tells us. The variable bits_set tracks the number
942 * of bits that have been set so far. End_bit is the number
943 * of the last bit to be set in this word plus one.
944 */
945 if (bit) {
946 end_bit = min(bit + bits_to_set, (uint)NBWORD);
947 mask = ((1U << (end_bit - bit)) - 1) << bit;
948 *wordp |= mask;
949 wordp++;
950 bits_set = end_bit - bit;
951 } else {
952 bits_set = 0;
953 }
954
955 /*
956 * Now set bits a whole word at a time that are between
957 * first_bit and last_bit.
958 */
959 while ((bits_to_set - bits_set) >= NBWORD) {
960 *wordp = 0xffffffff;
961 bits_set += NBWORD;
962 wordp++;
963 }
964
965 /*
966 * Finally, set any bits left to be set in one last partial word.
967 */
968 end_bit = bits_to_set - bits_set;
969 if (end_bit) {
970 mask = (1U << end_bit) - 1;
971 *wordp |= mask;
972 }
973}
974
975/*
976 * Mark bytes first through last inclusive as dirty in the buf
977 * item's bitmap.
978 */
979void
980xfs_buf_item_log(
981 struct xfs_buf_log_item *bip,
982 uint first,
983 uint last)
984{
985 int i;
986 uint start;
987 uint end;
988 struct xfs_buf *bp = bip->bli_buf;
989
990 /*
991 * walk each buffer segment and mark them dirty appropriately.
992 */
993 start = 0;
994 for (i = 0; i < bip->bli_format_count; i++) {
995 if (start > last)
996 break;
997 end = start + BBTOB(bp->b_maps[i].bm_len) - 1;
998
999 /* skip to the map that includes the first byte to log */
1000 if (first > end) {
1001 start += BBTOB(bp->b_maps[i].bm_len);
1002 continue;
1003 }
1004
1005 /*
1006 * Trim the range to this segment and mark it in the bitmap.
1007 * Note that we must convert buffer offsets to segment relative
1008 * offsets (e.g., the first byte of each segment is byte 0 of
1009 * that segment).
1010 */
1011 if (first < start)
1012 first = start;
1013 if (end > last)
1014 end = last;
1015 xfs_buf_item_log_segment(first - start, end - start,
1016 &bip->bli_formats[i].blf_data_map[0]);
1017
1018 start += BBTOB(bp->b_maps[i].bm_len);
1019 }
1020}
1021
1022
1023/*
1024 * Return true if the buffer has any ranges logged/dirtied by a transaction,
1025 * false otherwise.
1026 */
1027bool
1028xfs_buf_item_dirty_format(
1029 struct xfs_buf_log_item *bip)
1030{
1031 int i;
1032
1033 for (i = 0; i < bip->bli_format_count; i++) {
1034 if (!xfs_bitmap_empty(bip->bli_formats[i].blf_data_map,
1035 bip->bli_formats[i].blf_map_size))
1036 return true;
1037 }
1038
1039 return false;
1040}
1041
1042STATIC void
1043xfs_buf_item_free(
1044 struct xfs_buf_log_item *bip)
1045{
1046 xfs_buf_item_free_format(bip);
1047 kvfree(bip->bli_item.li_lv_shadow);
1048 kmem_cache_free(xfs_buf_item_cache, bip);
1049}
1050
1051/*
1052 * xfs_buf_item_relse() is called when the buf log item is no longer needed.
1053 */
1054void
1055xfs_buf_item_relse(
1056 struct xfs_buf *bp)
1057{
1058 struct xfs_buf_log_item *bip = bp->b_log_item;
1059
1060 trace_xfs_buf_item_relse(bp, _RET_IP_);
1061 ASSERT(!test_bit(XFS_LI_IN_AIL, &bip->bli_item.li_flags));
1062
1063 if (atomic_read(&bip->bli_refcount))
1064 return;
1065 bp->b_log_item = NULL;
1066 xfs_buf_rele(bp);
1067 xfs_buf_item_free(bip);
1068}
1069
1070void
1071xfs_buf_item_done(
1072 struct xfs_buf *bp)
1073{
1074 /*
1075 * If we are forcibly shutting down, this may well be off the AIL
1076 * already. That's because we simulate the log-committed callbacks to
1077 * unpin these buffers. Or we may never have put this item on AIL
1078 * because of the transaction was aborted forcibly.
1079 * xfs_trans_ail_delete() takes care of these.
1080 *
1081 * Either way, AIL is useless if we're forcing a shutdown.
1082 *
1083 * Note that log recovery writes might have buffer items that are not on
1084 * the AIL even when the file system is not shut down.
1085 */
1086 xfs_trans_ail_delete(&bp->b_log_item->bli_item,
1087 (bp->b_flags & _XBF_LOGRECOVERY) ? 0 :
1088 SHUTDOWN_CORRUPT_INCORE);
1089 xfs_buf_item_relse(bp);
1090}