xref: /linux/fs/xfs/xfs_trans_buf.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2002,2005 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_mount.h"
13 #include "xfs_trans.h"
14 #include "xfs_buf_item.h"
15 #include "xfs_trans_priv.h"
16 #include "xfs_trace.h"
17 
18 /*
19  * Check to see if a buffer matching the given parameters is already
20  * a part of the given transaction.
21  */
22 STATIC struct xfs_buf *
23 xfs_trans_buf_item_match(
24 	struct xfs_trans	*tp,
25 	struct xfs_buftarg	*target,
26 	struct xfs_buf_map	*map,
27 	int			nmaps)
28 {
29 	struct xfs_log_item	*lip;
30 	struct xfs_buf_log_item	*blip;
31 	int			len = 0;
32 	int			i;
33 
34 	for (i = 0; i < nmaps; i++)
35 		len += map[i].bm_len;
36 
37 	list_for_each_entry(lip, &tp->t_items, li_trans) {
38 		blip = (struct xfs_buf_log_item *)lip;
39 		if (blip->bli_item.li_type == XFS_LI_BUF &&
40 		    blip->bli_buf->b_target == target &&
41 		    xfs_buf_daddr(blip->bli_buf) == map[0].bm_bn &&
42 		    blip->bli_buf->b_length == len) {
43 			ASSERT(blip->bli_buf->b_map_count == nmaps);
44 			return blip->bli_buf;
45 		}
46 	}
47 
48 	return NULL;
49 }
50 
51 /*
52  * Add the locked buffer to the transaction.
53  *
54  * The buffer must be locked, and it cannot be associated with any
55  * transaction.
56  *
57  * If the buffer does not yet have a buf log item associated with it,
58  * then allocate one for it.  Then add the buf item to the transaction.
59  */
60 STATIC void
61 _xfs_trans_bjoin(
62 	struct xfs_trans	*tp,
63 	struct xfs_buf		*bp,
64 	int			reset_recur)
65 {
66 	struct xfs_buf_log_item	*bip;
67 
68 	ASSERT(bp->b_transp == NULL);
69 
70 	/*
71 	 * The xfs_buf_log_item pointer is stored in b_log_item.  If
72 	 * it doesn't have one yet, then allocate one and initialize it.
73 	 * The checks to see if one is there are in xfs_buf_item_init().
74 	 */
75 	xfs_buf_item_init(bp, tp->t_mountp);
76 	bip = bp->b_log_item;
77 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
78 	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
79 	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
80 	if (reset_recur)
81 		bip->bli_recur = 0;
82 
83 	/*
84 	 * Take a reference for this transaction on the buf item.
85 	 */
86 	atomic_inc(&bip->bli_refcount);
87 
88 	/*
89 	 * Attach the item to the transaction so we can find it in
90 	 * xfs_trans_get_buf() and friends.
91 	 */
92 	xfs_trans_add_item(tp, &bip->bli_item);
93 	bp->b_transp = tp;
94 
95 }
96 
97 void
98 xfs_trans_bjoin(
99 	struct xfs_trans	*tp,
100 	struct xfs_buf		*bp)
101 {
102 	_xfs_trans_bjoin(tp, bp, 0);
103 	trace_xfs_trans_bjoin(bp->b_log_item);
104 }
105 
106 /*
107  * Get and lock the buffer for the caller if it is not already
108  * locked within the given transaction.  If it is already locked
109  * within the transaction, just increment its lock recursion count
110  * and return a pointer to it.
111  *
112  * If the transaction pointer is NULL, make this just a normal
113  * get_buf() call.
114  */
115 int
116 xfs_trans_get_buf_map(
117 	struct xfs_trans	*tp,
118 	struct xfs_buftarg	*target,
119 	struct xfs_buf_map	*map,
120 	int			nmaps,
121 	xfs_buf_flags_t		flags,
122 	struct xfs_buf		**bpp)
123 {
124 	struct xfs_buf		*bp;
125 	struct xfs_buf_log_item	*bip;
126 	int			error;
127 
128 	*bpp = NULL;
129 	if (!tp)
130 		return xfs_buf_get_map(target, map, nmaps, flags, bpp);
131 
132 	/*
133 	 * If we find the buffer in the cache with this transaction
134 	 * pointer in its b_fsprivate2 field, then we know we already
135 	 * have it locked.  In this case we just increment the lock
136 	 * recursion count and return the buffer to the caller.
137 	 */
138 	bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
139 	if (bp != NULL) {
140 		ASSERT(xfs_buf_islocked(bp));
141 		if (xfs_is_shutdown(tp->t_mountp)) {
142 			xfs_buf_stale(bp);
143 			bp->b_flags |= XBF_DONE;
144 		}
145 
146 		ASSERT(bp->b_transp == tp);
147 		bip = bp->b_log_item;
148 		ASSERT(bip != NULL);
149 		ASSERT(atomic_read(&bip->bli_refcount) > 0);
150 		bip->bli_recur++;
151 		trace_xfs_trans_get_buf_recur(bip);
152 		*bpp = bp;
153 		return 0;
154 	}
155 
156 	error = xfs_buf_get_map(target, map, nmaps, flags, &bp);
157 	if (error)
158 		return error;
159 
160 	ASSERT(!bp->b_error);
161 
162 	_xfs_trans_bjoin(tp, bp, 1);
163 	trace_xfs_trans_get_buf(bp->b_log_item);
164 	*bpp = bp;
165 	return 0;
166 }
167 
168 /*
169  * Get and lock the superblock buffer for the given transaction.
170  */
171 static struct xfs_buf *
172 __xfs_trans_getsb(
173 	struct xfs_trans	*tp,
174 	struct xfs_buf		*bp)
175 {
176 	/*
177 	 * Just increment the lock recursion count if the buffer is already
178 	 * attached to this transaction.
179 	 */
180 	if (bp->b_transp == tp) {
181 		struct xfs_buf_log_item	*bip = bp->b_log_item;
182 
183 		ASSERT(bip != NULL);
184 		ASSERT(atomic_read(&bip->bli_refcount) > 0);
185 		bip->bli_recur++;
186 
187 		trace_xfs_trans_getsb_recur(bip);
188 	} else {
189 		xfs_buf_lock(bp);
190 		xfs_buf_hold(bp);
191 		_xfs_trans_bjoin(tp, bp, 1);
192 
193 		trace_xfs_trans_getsb(bp->b_log_item);
194 	}
195 
196 	return bp;
197 }
198 
199 struct xfs_buf *
200 xfs_trans_getsb(
201 	struct xfs_trans	*tp)
202 {
203 	return __xfs_trans_getsb(tp, tp->t_mountp->m_sb_bp);
204 }
205 
206 struct xfs_buf *
207 xfs_trans_getrtsb(
208 	struct xfs_trans	*tp)
209 {
210 	if (!tp->t_mountp->m_rtsb_bp)
211 		return NULL;
212 	return __xfs_trans_getsb(tp, tp->t_mountp->m_rtsb_bp);
213 }
214 
215 /*
216  * Get and lock the buffer for the caller if it is not already
217  * locked within the given transaction.  If it has not yet been
218  * read in, read it from disk. If it is already locked
219  * within the transaction and already read in, just increment its
220  * lock recursion count and return a pointer to it.
221  *
222  * If the transaction pointer is NULL, make this just a normal
223  * read_buf() call.
224  */
225 int
226 xfs_trans_read_buf_map(
227 	struct xfs_mount	*mp,
228 	struct xfs_trans	*tp,
229 	struct xfs_buftarg	*target,
230 	struct xfs_buf_map	*map,
231 	int			nmaps,
232 	xfs_buf_flags_t		flags,
233 	struct xfs_buf		**bpp,
234 	const struct xfs_buf_ops *ops)
235 {
236 	struct xfs_buf		*bp = NULL;
237 	struct xfs_buf_log_item	*bip;
238 	int			error;
239 
240 	*bpp = NULL;
241 	/*
242 	 * If we find the buffer in the cache with this transaction
243 	 * pointer in its b_fsprivate2 field, then we know we already
244 	 * have it locked.  If it is already read in we just increment
245 	 * the lock recursion count and return the buffer to the caller.
246 	 * If the buffer is not yet read in, then we read it in, increment
247 	 * the lock recursion count, and return it to the caller.
248 	 */
249 	if (tp)
250 		bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
251 	if (bp) {
252 		ASSERT(xfs_buf_islocked(bp));
253 		ASSERT(bp->b_transp == tp);
254 		ASSERT(bp->b_log_item != NULL);
255 		ASSERT(!bp->b_error);
256 		ASSERT(bp->b_flags & XBF_DONE);
257 
258 		/*
259 		 * We never locked this buf ourselves, so we shouldn't
260 		 * brelse it either. Just get out.
261 		 */
262 		if (xfs_is_shutdown(mp)) {
263 			trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
264 			return -EIO;
265 		}
266 
267 		/*
268 		 * Check if the caller is trying to read a buffer that is
269 		 * already attached to the transaction yet has no buffer ops
270 		 * assigned.  Ops are usually attached when the buffer is
271 		 * attached to the transaction, or by the read caller if
272 		 * special circumstances.  That didn't happen, which is not
273 		 * how this is supposed to go.
274 		 *
275 		 * If the buffer passes verification we'll let this go, but if
276 		 * not we have to shut down.  Let the transaction cleanup code
277 		 * release this buffer when it kills the tranaction.
278 		 */
279 		ASSERT(bp->b_ops != NULL);
280 		error = xfs_buf_reverify(bp, ops);
281 		if (error) {
282 			xfs_buf_ioerror_alert(bp, __return_address);
283 
284 			if (tp->t_flags & XFS_TRANS_DIRTY)
285 				xfs_force_shutdown(tp->t_mountp,
286 						SHUTDOWN_META_IO_ERROR);
287 
288 			/* bad CRC means corrupted metadata */
289 			if (error == -EFSBADCRC)
290 				error = -EFSCORRUPTED;
291 			return error;
292 		}
293 
294 		bip = bp->b_log_item;
295 		bip->bli_recur++;
296 
297 		ASSERT(atomic_read(&bip->bli_refcount) > 0);
298 		trace_xfs_trans_read_buf_recur(bip);
299 		ASSERT(bp->b_ops != NULL || ops == NULL);
300 		*bpp = bp;
301 		return 0;
302 	}
303 
304 	error = xfs_buf_read_map(target, map, nmaps, flags, &bp, ops,
305 			__return_address);
306 	switch (error) {
307 	case 0:
308 		break;
309 	default:
310 		if (tp && (tp->t_flags & XFS_TRANS_DIRTY))
311 			xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
312 		fallthrough;
313 	case -ENOMEM:
314 	case -EAGAIN:
315 		return error;
316 	}
317 
318 	if (xfs_is_shutdown(mp)) {
319 		xfs_buf_relse(bp);
320 		trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
321 		return -EIO;
322 	}
323 
324 	if (tp) {
325 		_xfs_trans_bjoin(tp, bp, 1);
326 		trace_xfs_trans_read_buf(bp->b_log_item);
327 	}
328 	ASSERT(bp->b_ops != NULL || ops == NULL);
329 	*bpp = bp;
330 	return 0;
331 
332 }
333 
334 /* Has this buffer been dirtied by anyone? */
335 bool
336 xfs_trans_buf_is_dirty(
337 	struct xfs_buf		*bp)
338 {
339 	struct xfs_buf_log_item	*bip = bp->b_log_item;
340 
341 	if (!bip)
342 		return false;
343 	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
344 	return test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
345 }
346 
347 /*
348  * Release a buffer previously joined to the transaction. If the buffer is
349  * modified within this transaction, decrement the recursion count but do not
350  * release the buffer even if the count goes to 0. If the buffer is not modified
351  * within the transaction, decrement the recursion count and release the buffer
352  * if the recursion count goes to 0.
353  *
354  * If the buffer is to be released and it was not already dirty before this
355  * transaction began, then also free the buf_log_item associated with it.
356  *
357  * If the transaction pointer is NULL, this is a normal xfs_buf_relse() call.
358  */
359 void
360 xfs_trans_brelse(
361 	struct xfs_trans	*tp,
362 	struct xfs_buf		*bp)
363 {
364 	struct xfs_buf_log_item	*bip = bp->b_log_item;
365 
366 	ASSERT(bp->b_transp == tp);
367 
368 	if (!tp) {
369 		xfs_buf_relse(bp);
370 		return;
371 	}
372 
373 	trace_xfs_trans_brelse(bip);
374 	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
375 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
376 
377 	/*
378 	 * If the release is for a recursive lookup, then decrement the count
379 	 * and return.
380 	 */
381 	if (bip->bli_recur > 0) {
382 		bip->bli_recur--;
383 		return;
384 	}
385 
386 	/*
387 	 * If the buffer is invalidated or dirty in this transaction, we can't
388 	 * release it until we commit.
389 	 */
390 	if (test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags))
391 		return;
392 	if (bip->bli_flags & XFS_BLI_STALE)
393 		return;
394 
395 	/*
396 	 * Unlink the log item from the transaction and clear the hold flag, if
397 	 * set. We wouldn't want the next user of the buffer to get confused.
398 	 */
399 	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
400 	xfs_trans_del_item(&bip->bli_item);
401 	bip->bli_flags &= ~XFS_BLI_HOLD;
402 
403 	/* drop the reference to the bli */
404 	xfs_buf_item_put(bip);
405 
406 	bp->b_transp = NULL;
407 	xfs_buf_relse(bp);
408 }
409 
410 /*
411  * Forcibly detach a buffer previously joined to the transaction.  The caller
412  * will retain its locked reference to the buffer after this function returns.
413  * The buffer must be completely clean and must not be held to the transaction.
414  */
415 void
416 xfs_trans_bdetach(
417 	struct xfs_trans	*tp,
418 	struct xfs_buf		*bp)
419 {
420 	struct xfs_buf_log_item	*bip = bp->b_log_item;
421 
422 	ASSERT(tp != NULL);
423 	ASSERT(bp->b_transp == tp);
424 	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
425 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
426 
427 	trace_xfs_trans_bdetach(bip);
428 
429 	/*
430 	 * Erase all recursion count, since we're removing this buffer from the
431 	 * transaction.
432 	 */
433 	bip->bli_recur = 0;
434 
435 	/*
436 	 * The buffer must be completely clean.  Specifically, it had better
437 	 * not be dirty, stale, logged, ordered, or held to the transaction.
438 	 */
439 	ASSERT(!test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags));
440 	ASSERT(!(bip->bli_flags & XFS_BLI_DIRTY));
441 	ASSERT(!(bip->bli_flags & XFS_BLI_HOLD));
442 	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
443 	ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED));
444 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
445 
446 	/* Unlink the log item from the transaction and drop the log item. */
447 	xfs_trans_del_item(&bip->bli_item);
448 	xfs_buf_item_put(bip);
449 	bp->b_transp = NULL;
450 }
451 
452 /*
453  * Mark the buffer as not needing to be unlocked when the buf item's
454  * iop_committing() routine is called.  The buffer must already be locked
455  * and associated with the given transaction.
456  */
457 /* ARGSUSED */
458 void
459 xfs_trans_bhold(
460 	xfs_trans_t		*tp,
461 	struct xfs_buf		*bp)
462 {
463 	struct xfs_buf_log_item	*bip = bp->b_log_item;
464 
465 	ASSERT(bp->b_transp == tp);
466 	ASSERT(bip != NULL);
467 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
468 	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
469 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
470 
471 	bip->bli_flags |= XFS_BLI_HOLD;
472 	trace_xfs_trans_bhold(bip);
473 }
474 
475 /*
476  * Cancel the previous buffer hold request made on this buffer
477  * for this transaction.
478  */
479 void
480 xfs_trans_bhold_release(
481 	xfs_trans_t		*tp,
482 	struct xfs_buf		*bp)
483 {
484 	struct xfs_buf_log_item	*bip = bp->b_log_item;
485 
486 	ASSERT(bp->b_transp == tp);
487 	ASSERT(bip != NULL);
488 	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
489 	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
490 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
491 	ASSERT(bip->bli_flags & XFS_BLI_HOLD);
492 
493 	bip->bli_flags &= ~XFS_BLI_HOLD;
494 	trace_xfs_trans_bhold_release(bip);
495 }
496 
497 /*
498  * Mark a buffer dirty in the transaction.
499  */
500 void
501 xfs_trans_dirty_buf(
502 	struct xfs_trans	*tp,
503 	struct xfs_buf		*bp)
504 {
505 	struct xfs_buf_log_item	*bip = bp->b_log_item;
506 
507 	ASSERT(bp->b_transp == tp);
508 	ASSERT(bip != NULL);
509 
510 	/*
511 	 * Mark the buffer as needing to be written out eventually,
512 	 * and set its iodone function to remove the buffer's buf log
513 	 * item from the AIL and free it when the buffer is flushed
514 	 * to disk.
515 	 */
516 	bp->b_flags |= XBF_DONE;
517 
518 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
519 
520 	/*
521 	 * If we invalidated the buffer within this transaction, then
522 	 * cancel the invalidation now that we're dirtying the buffer
523 	 * again.  There are no races with the code in xfs_buf_item_unpin(),
524 	 * because we have a reference to the buffer this entire time.
525 	 */
526 	if (bip->bli_flags & XFS_BLI_STALE) {
527 		bip->bli_flags &= ~XFS_BLI_STALE;
528 		ASSERT(bp->b_flags & XBF_STALE);
529 		bp->b_flags &= ~XBF_STALE;
530 		bip->__bli_format.blf_flags &= ~XFS_BLF_CANCEL;
531 	}
532 	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
533 
534 	tp->t_flags |= XFS_TRANS_DIRTY;
535 	set_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
536 }
537 
538 /*
539  * This is called to mark bytes first through last inclusive of the given
540  * buffer as needing to be logged when the transaction is committed.
541  * The buffer must already be associated with the given transaction.
542  *
543  * First and last are numbers relative to the beginning of this buffer,
544  * so the first byte in the buffer is numbered 0 regardless of the
545  * value of b_blkno.
546  */
547 void
548 xfs_trans_log_buf(
549 	struct xfs_trans	*tp,
550 	struct xfs_buf		*bp,
551 	uint			first,
552 	uint			last)
553 {
554 	struct xfs_buf_log_item	*bip = bp->b_log_item;
555 
556 	ASSERT(first <= last && last < BBTOB(bp->b_length));
557 	ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED));
558 
559 	xfs_trans_dirty_buf(tp, bp);
560 
561 	trace_xfs_trans_log_buf(bip);
562 	xfs_buf_item_log(bip, first, last);
563 }
564 
565 
566 /*
567  * Invalidate a buffer that is being used within a transaction.
568  *
569  * Typically this is because the blocks in the buffer are being freed, so we
570  * need to prevent it from being written out when we're done.  Allowing it
571  * to be written again might overwrite data in the free blocks if they are
572  * reallocated to a file.
573  *
574  * We prevent the buffer from being written out by marking it stale.  We can't
575  * get rid of the buf log item at this point because the buffer may still be
576  * pinned by another transaction.  If that is the case, then we'll wait until
577  * the buffer is committed to disk for the last time (we can tell by the ref
578  * count) and free it in xfs_buf_item_unpin().  Until that happens we will
579  * keep the buffer locked so that the buffer and buf log item are not reused.
580  *
581  * We also set the XFS_BLF_CANCEL flag in the buf log format structure and log
582  * the buf item.  This will be used at recovery time to determine that copies
583  * of the buffer in the log before this should not be replayed.
584  *
585  * We mark the item descriptor and the transaction dirty so that we'll hold
586  * the buffer until after the commit.
587  *
588  * Since we're invalidating the buffer, we also clear the state about which
589  * parts of the buffer have been logged.  We also clear the flag indicating
590  * that this is an inode buffer since the data in the buffer will no longer
591  * be valid.
592  *
593  * We set the stale bit in the buffer as well since we're getting rid of it.
594  */
595 void
596 xfs_trans_binval(
597 	xfs_trans_t		*tp,
598 	struct xfs_buf		*bp)
599 {
600 	struct xfs_buf_log_item	*bip = bp->b_log_item;
601 	int			i;
602 
603 	ASSERT(bp->b_transp == tp);
604 	ASSERT(bip != NULL);
605 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
606 
607 	trace_xfs_trans_binval(bip);
608 
609 	if (bip->bli_flags & XFS_BLI_STALE) {
610 		/*
611 		 * If the buffer is already invalidated, then
612 		 * just return.
613 		 */
614 		ASSERT(bp->b_flags & XBF_STALE);
615 		ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
616 		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_INODE_BUF));
617 		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLFT_MASK));
618 		ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
619 		ASSERT(test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags));
620 		ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
621 		return;
622 	}
623 
624 	xfs_buf_stale(bp);
625 
626 	bip->bli_flags |= XFS_BLI_STALE;
627 	bip->bli_flags &= ~(XFS_BLI_INODE_BUF | XFS_BLI_LOGGED | XFS_BLI_DIRTY);
628 	bip->__bli_format.blf_flags &= ~XFS_BLF_INODE_BUF;
629 	bip->__bli_format.blf_flags |= XFS_BLF_CANCEL;
630 	bip->__bli_format.blf_flags &= ~XFS_BLFT_MASK;
631 	for (i = 0; i < bip->bli_format_count; i++) {
632 		memset(bip->bli_formats[i].blf_data_map, 0,
633 		       (bip->bli_formats[i].blf_map_size * sizeof(uint)));
634 	}
635 	set_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
636 	tp->t_flags |= XFS_TRANS_DIRTY;
637 }
638 
639 /*
640  * This call is used to indicate that the buffer contains on-disk inodes which
641  * must be handled specially during recovery.  They require special handling
642  * because only the di_next_unlinked from the inodes in the buffer should be
643  * recovered.  The rest of the data in the buffer is logged via the inodes
644  * themselves.
645  *
646  * All we do is set the XFS_BLI_INODE_BUF flag in the items flags so it can be
647  * transferred to the buffer's log format structure so that we'll know what to
648  * do at recovery time.
649  */
650 void
651 xfs_trans_inode_buf(
652 	xfs_trans_t		*tp,
653 	struct xfs_buf		*bp)
654 {
655 	struct xfs_buf_log_item	*bip = bp->b_log_item;
656 
657 	ASSERT(bp->b_transp == tp);
658 	ASSERT(bip != NULL);
659 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
660 
661 	bip->bli_flags |= XFS_BLI_INODE_BUF;
662 	bp->b_flags |= _XBF_INODES;
663 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
664 }
665 
666 /*
667  * This call is used to indicate that the buffer is going to
668  * be staled and was an inode buffer. This means it gets
669  * special processing during unpin - where any inodes
670  * associated with the buffer should be removed from ail.
671  * There is also special processing during recovery,
672  * any replay of the inodes in the buffer needs to be
673  * prevented as the buffer may have been reused.
674  */
675 void
676 xfs_trans_stale_inode_buf(
677 	xfs_trans_t		*tp,
678 	struct xfs_buf		*bp)
679 {
680 	struct xfs_buf_log_item	*bip = bp->b_log_item;
681 
682 	ASSERT(bp->b_transp == tp);
683 	ASSERT(bip != NULL);
684 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
685 
686 	bip->bli_flags |= XFS_BLI_STALE_INODE;
687 	bp->b_flags |= _XBF_INODES;
688 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
689 }
690 
691 /*
692  * Mark the buffer as being one which contains newly allocated
693  * inodes.  We need to make sure that even if this buffer is
694  * relogged as an 'inode buf' we still recover all of the inode
695  * images in the face of a crash.  This works in coordination with
696  * xfs_buf_item_committed() to ensure that the buffer remains in the
697  * AIL at its original location even after it has been relogged.
698  */
699 /* ARGSUSED */
700 void
701 xfs_trans_inode_alloc_buf(
702 	xfs_trans_t		*tp,
703 	struct xfs_buf		*bp)
704 {
705 	struct xfs_buf_log_item	*bip = bp->b_log_item;
706 
707 	ASSERT(bp->b_transp == tp);
708 	ASSERT(bip != NULL);
709 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
710 
711 	bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
712 	bp->b_flags |= _XBF_INODES;
713 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
714 }
715 
716 /*
717  * Mark the buffer as ordered for this transaction. This means that the contents
718  * of the buffer are not recorded in the transaction but it is tracked in the
719  * AIL as though it was. This allows us to record logical changes in
720  * transactions rather than the physical changes we make to the buffer without
721  * changing writeback ordering constraints of metadata buffers.
722  */
723 bool
724 xfs_trans_ordered_buf(
725 	struct xfs_trans	*tp,
726 	struct xfs_buf		*bp)
727 {
728 	struct xfs_buf_log_item	*bip = bp->b_log_item;
729 
730 	ASSERT(bp->b_transp == tp);
731 	ASSERT(bip != NULL);
732 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
733 
734 	if (xfs_buf_item_dirty_format(bip))
735 		return false;
736 
737 	bip->bli_flags |= XFS_BLI_ORDERED;
738 	trace_xfs_buf_item_ordered(bip);
739 
740 	/*
741 	 * We don't log a dirty range of an ordered buffer but it still needs
742 	 * to be marked dirty and that it has been logged.
743 	 */
744 	xfs_trans_dirty_buf(tp, bp);
745 	return true;
746 }
747 
748 /*
749  * Set the type of the buffer for log recovery so that it can correctly identify
750  * and hence attach the correct buffer ops to the buffer after replay.
751  */
752 void
753 xfs_trans_buf_set_type(
754 	struct xfs_trans	*tp,
755 	struct xfs_buf		*bp,
756 	enum xfs_blft		type)
757 {
758 	struct xfs_buf_log_item	*bip = bp->b_log_item;
759 
760 	if (!tp)
761 		return;
762 
763 	ASSERT(bp->b_transp == tp);
764 	ASSERT(bip != NULL);
765 	ASSERT(atomic_read(&bip->bli_refcount) > 0);
766 
767 	xfs_blft_to_flags(&bip->__bli_format, type);
768 }
769 
770 void
771 xfs_trans_buf_copy_type(
772 	struct xfs_buf		*dst_bp,
773 	struct xfs_buf		*src_bp)
774 {
775 	struct xfs_buf_log_item	*sbip = src_bp->b_log_item;
776 	struct xfs_buf_log_item	*dbip = dst_bp->b_log_item;
777 	enum xfs_blft		type;
778 
779 	type = xfs_blft_from_flags(&sbip->__bli_format);
780 	xfs_blft_to_flags(&dbip->__bli_format, type);
781 }
782 
783 /*
784  * Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
785  * dquots. However, unlike in inode buffer recovery, dquot buffers get
786  * recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
787  * The only thing that makes dquot buffers different from regular
788  * buffers is that we must not replay dquot bufs when recovering
789  * if a _corresponding_ quotaoff has happened. We also have to distinguish
790  * between usr dquot bufs and grp dquot bufs, because usr and grp quotas
791  * can be turned off independently.
792  */
793 /* ARGSUSED */
794 void
795 xfs_trans_dquot_buf(
796 	xfs_trans_t		*tp,
797 	struct xfs_buf		*bp,
798 	uint			type)
799 {
800 	struct xfs_buf_log_item	*bip = bp->b_log_item;
801 
802 	ASSERT(type == XFS_BLF_UDQUOT_BUF ||
803 	       type == XFS_BLF_PDQUOT_BUF ||
804 	       type == XFS_BLF_GDQUOT_BUF);
805 
806 	bip->__bli_format.blf_flags |= type;
807 
808 	switch (type) {
809 	case XFS_BLF_UDQUOT_BUF:
810 		type = XFS_BLFT_UDQUOT_BUF;
811 		break;
812 	case XFS_BLF_PDQUOT_BUF:
813 		type = XFS_BLFT_PDQUOT_BUF;
814 		break;
815 	case XFS_BLF_GDQUOT_BUF:
816 		type = XFS_BLFT_GDQUOT_BUF;
817 		break;
818 	default:
819 		type = XFS_BLFT_UNKNOWN_BUF;
820 		break;
821 	}
822 
823 	bp->b_flags |= _XBF_DQUOTS;
824 	xfs_trans_buf_set_type(tp, bp, type);
825 }
826