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v4.10.11
 
  1/*
  2 * Copyright (c) 2000-2002,2005 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_shared.h"
 21#include "xfs_format.h"
 22#include "xfs_log_format.h"
 23#include "xfs_trans_resv.h"
 24#include "xfs_mount.h"
 25#include "xfs_inode.h"
 26#include "xfs_trans.h"
 27#include "xfs_buf_item.h"
 28#include "xfs_trans_priv.h"
 29#include "xfs_error.h"
 30#include "xfs_trace.h"
 31
 32/*
 33 * Check to see if a buffer matching the given parameters is already
 34 * a part of the given transaction.
 35 */
 36STATIC struct xfs_buf *
 37xfs_trans_buf_item_match(
 38	struct xfs_trans	*tp,
 39	struct xfs_buftarg	*target,
 40	struct xfs_buf_map	*map,
 41	int			nmaps)
 42{
 43	struct xfs_log_item_desc *lidp;
 44	struct xfs_buf_log_item	*blip;
 45	int			len = 0;
 46	int			i;
 47
 48	for (i = 0; i < nmaps; i++)
 49		len += map[i].bm_len;
 50
 51	list_for_each_entry(lidp, &tp->t_items, lid_trans) {
 52		blip = (struct xfs_buf_log_item *)lidp->lid_item;
 53		if (blip->bli_item.li_type == XFS_LI_BUF &&
 54		    blip->bli_buf->b_target == target &&
 55		    XFS_BUF_ADDR(blip->bli_buf) == map[0].bm_bn &&
 56		    blip->bli_buf->b_length == len) {
 57			ASSERT(blip->bli_buf->b_map_count == nmaps);
 58			return blip->bli_buf;
 59		}
 60	}
 61
 62	return NULL;
 63}
 64
 65/*
 66 * Add the locked buffer to the transaction.
 67 *
 68 * The buffer must be locked, and it cannot be associated with any
 69 * transaction.
 70 *
 71 * If the buffer does not yet have a buf log item associated with it,
 72 * then allocate one for it.  Then add the buf item to the transaction.
 73 */
 74STATIC void
 75_xfs_trans_bjoin(
 76	struct xfs_trans	*tp,
 77	struct xfs_buf		*bp,
 78	int			reset_recur)
 79{
 80	struct xfs_buf_log_item	*bip;
 81
 82	ASSERT(bp->b_transp == NULL);
 83
 84	/*
 85	 * The xfs_buf_log_item pointer is stored in b_fsprivate.  If
 86	 * it doesn't have one yet, then allocate one and initialize it.
 87	 * The checks to see if one is there are in xfs_buf_item_init().
 88	 */
 89	xfs_buf_item_init(bp, tp->t_mountp);
 90	bip = bp->b_fspriv;
 91	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
 92	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
 93	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
 94	if (reset_recur)
 95		bip->bli_recur = 0;
 96
 97	/*
 98	 * Take a reference for this transaction on the buf item.
 99	 */
100	atomic_inc(&bip->bli_refcount);
101
102	/*
103	 * Get a log_item_desc to point at the new item.
 
104	 */
105	xfs_trans_add_item(tp, &bip->bli_item);
106
107	/*
108	 * Initialize b_fsprivate2 so we can find it with incore_match()
109	 * in xfs_trans_get_buf() and friends above.
110	 */
111	bp->b_transp = tp;
112
113}
114
115void
116xfs_trans_bjoin(
117	struct xfs_trans	*tp,
118	struct xfs_buf		*bp)
119{
120	_xfs_trans_bjoin(tp, bp, 0);
121	trace_xfs_trans_bjoin(bp->b_fspriv);
122}
123
124/*
125 * Get and lock the buffer for the caller if it is not already
126 * locked within the given transaction.  If it is already locked
127 * within the transaction, just increment its lock recursion count
128 * and return a pointer to it.
129 *
130 * If the transaction pointer is NULL, make this just a normal
131 * get_buf() call.
132 */
133struct xfs_buf *
134xfs_trans_get_buf_map(
135	struct xfs_trans	*tp,
136	struct xfs_buftarg	*target,
137	struct xfs_buf_map	*map,
138	int			nmaps,
139	xfs_buf_flags_t		flags)
 
140{
141	xfs_buf_t		*bp;
142	xfs_buf_log_item_t	*bip;
 
143
 
144	if (!tp)
145		return xfs_buf_get_map(target, map, nmaps, flags);
146
147	/*
148	 * If we find the buffer in the cache with this transaction
149	 * pointer in its b_fsprivate2 field, then we know we already
150	 * have it locked.  In this case we just increment the lock
151	 * recursion count and return the buffer to the caller.
152	 */
153	bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
154	if (bp != NULL) {
155		ASSERT(xfs_buf_islocked(bp));
156		if (XFS_FORCED_SHUTDOWN(tp->t_mountp)) {
157			xfs_buf_stale(bp);
158			bp->b_flags |= XBF_DONE;
159		}
160
161		ASSERT(bp->b_transp == tp);
162		bip = bp->b_fspriv;
163		ASSERT(bip != NULL);
164		ASSERT(atomic_read(&bip->bli_refcount) > 0);
165		bip->bli_recur++;
166		trace_xfs_trans_get_buf_recur(bip);
167		return bp;
 
168	}
169
170	bp = xfs_buf_get_map(target, map, nmaps, flags);
171	if (bp == NULL) {
172		return NULL;
173	}
174
175	ASSERT(!bp->b_error);
176
177	_xfs_trans_bjoin(tp, bp, 1);
178	trace_xfs_trans_get_buf(bp->b_fspriv);
179	return bp;
 
180}
181
182/*
183 * Get and lock the superblock buffer of this file system for the
184 * given transaction.
185 *
186 * We don't need to use incore_match() here, because the superblock
187 * buffer is a private buffer which we keep a pointer to in the
188 * mount structure.
189 */
190xfs_buf_t *
191xfs_trans_getsb(xfs_trans_t	*tp,
192		struct xfs_mount *mp,
193		int		flags)
194{
195	xfs_buf_t		*bp;
196	xfs_buf_log_item_t	*bip;
197
198	/*
199	 * Default to just trying to lock the superblock buffer
200	 * if tp is NULL.
201	 */
202	if (tp == NULL)
203		return xfs_getsb(mp, flags);
204
205	/*
206	 * If the superblock buffer already has this transaction
207	 * pointer in its b_fsprivate2 field, then we know we already
208	 * have it locked.  In this case we just increment the lock
209	 * recursion count and return the buffer to the caller.
210	 */
211	bp = mp->m_sb_bp;
212	if (bp->b_transp == tp) {
213		bip = bp->b_fspriv;
214		ASSERT(bip != NULL);
215		ASSERT(atomic_read(&bip->bli_refcount) > 0);
216		bip->bli_recur++;
217		trace_xfs_trans_getsb_recur(bip);
218		return bp;
219	}
220
221	bp = xfs_getsb(mp, flags);
222	if (bp == NULL)
223		return NULL;
224
225	_xfs_trans_bjoin(tp, bp, 1);
226	trace_xfs_trans_getsb(bp->b_fspriv);
227	return bp;
228}
229
230/*
231 * Get and lock the buffer for the caller if it is not already
232 * locked within the given transaction.  If it has not yet been
233 * read in, read it from disk. If it is already locked
234 * within the transaction and already read in, just increment its
235 * lock recursion count and return a pointer to it.
236 *
237 * If the transaction pointer is NULL, make this just a normal
238 * read_buf() call.
239 */
240int
241xfs_trans_read_buf_map(
242	struct xfs_mount	*mp,
243	struct xfs_trans	*tp,
244	struct xfs_buftarg	*target,
245	struct xfs_buf_map	*map,
246	int			nmaps,
247	xfs_buf_flags_t		flags,
248	struct xfs_buf		**bpp,
249	const struct xfs_buf_ops *ops)
250{
251	struct xfs_buf		*bp = NULL;
252	struct xfs_buf_log_item	*bip;
253	int			error;
254
255	*bpp = NULL;
256	/*
257	 * If we find the buffer in the cache with this transaction
258	 * pointer in its b_fsprivate2 field, then we know we already
259	 * have it locked.  If it is already read in we just increment
260	 * the lock recursion count and return the buffer to the caller.
261	 * If the buffer is not yet read in, then we read it in, increment
262	 * the lock recursion count, and return it to the caller.
263	 */
264	if (tp)
265		bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
266	if (bp) {
267		ASSERT(xfs_buf_islocked(bp));
268		ASSERT(bp->b_transp == tp);
269		ASSERT(bp->b_fspriv != NULL);
270		ASSERT(!bp->b_error);
271		ASSERT(bp->b_flags & XBF_DONE);
272
273		/*
274		 * We never locked this buf ourselves, so we shouldn't
275		 * brelse it either. Just get out.
276		 */
277		if (XFS_FORCED_SHUTDOWN(mp)) {
278			trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
279			return -EIO;
280		}
281
282		bip = bp->b_fspriv;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
283		bip->bli_recur++;
284
285		ASSERT(atomic_read(&bip->bli_refcount) > 0);
286		trace_xfs_trans_read_buf_recur(bip);
 
287		*bpp = bp;
288		return 0;
289	}
290
291	bp = xfs_buf_read_map(target, map, nmaps, flags, ops);
292	if (!bp) {
293		if (!(flags & XBF_TRYLOCK))
294			return -ENOMEM;
295		return tp ? 0 : -EAGAIN;
296	}
297
298	/*
299	 * If we've had a read error, then the contents of the buffer are
300	 * invalid and should not be used. To ensure that a followup read tries
301	 * to pull the buffer from disk again, we clear the XBF_DONE flag and
302	 * mark the buffer stale. This ensures that anyone who has a current
303	 * reference to the buffer will interpret it's contents correctly and
304	 * future cache lookups will also treat it as an empty, uninitialised
305	 * buffer.
306	 */
307	if (bp->b_error) {
308		error = bp->b_error;
309		if (!XFS_FORCED_SHUTDOWN(mp))
310			xfs_buf_ioerror_alert(bp, __func__);
311		bp->b_flags &= ~XBF_DONE;
312		xfs_buf_stale(bp);
313
314		if (tp && (tp->t_flags & XFS_TRANS_DIRTY))
315			xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
316		xfs_buf_relse(bp);
317
318		/* bad CRC means corrupted metadata */
319		if (error == -EFSBADCRC)
320			error = -EFSCORRUPTED;
321		return error;
322	}
323
324	if (XFS_FORCED_SHUTDOWN(mp)) {
325		xfs_buf_relse(bp);
326		trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
327		return -EIO;
328	}
329
330	if (tp) {
331		_xfs_trans_bjoin(tp, bp, 1);
332		trace_xfs_trans_read_buf(bp->b_fspriv);
333	}
 
334	*bpp = bp;
335	return 0;
336
337}
338
 
 
 
 
 
 
 
 
 
 
 
 
 
339/*
340 * Release the buffer bp which was previously acquired with one of the
341 * xfs_trans_... buffer allocation routines if the buffer has not
342 * been modified within this transaction.  If the buffer is modified
343 * within this transaction, do decrement the recursion count but do
344 * not release the buffer even if the count goes to 0.  If the buffer is not
345 * modified within the transaction, decrement the recursion count and
346 * release the buffer if the recursion count goes to 0.
347 *
348 * If the buffer is to be released and it was not modified before
349 * this transaction began, then free the buf_log_item associated with it.
350 *
351 * If the transaction pointer is NULL, make this just a normal
352 * brelse() call.
353 */
354void
355xfs_trans_brelse(xfs_trans_t	*tp,
356		 xfs_buf_t	*bp)
 
357{
358	xfs_buf_log_item_t	*bip;
359
360	/*
361	 * Default to a normal brelse() call if the tp is NULL.
362	 */
363	if (tp == NULL) {
364		ASSERT(bp->b_transp == NULL);
365		xfs_buf_relse(bp);
366		return;
367	}
368
369	ASSERT(bp->b_transp == tp);
370	bip = bp->b_fspriv;
371	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
372	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
373	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
374	ASSERT(atomic_read(&bip->bli_refcount) > 0);
375
376	trace_xfs_trans_brelse(bip);
377
378	/*
379	 * If the release is just for a recursive lock,
380	 * then decrement the count and return.
381	 */
382	if (bip->bli_recur > 0) {
383		bip->bli_recur--;
384		return;
385	}
386
387	/*
388	 * If the buffer is dirty within this transaction, we can't
389	 * release it until we commit.
390	 */
391	if (bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY)
392		return;
393
394	/*
395	 * If the buffer has been invalidated, then we can't release
396	 * it until the transaction commits to disk unless it is re-dirtied
397	 * as part of this transaction.  This prevents us from pulling
398	 * the item from the AIL before we should.
399	 */
400	if (bip->bli_flags & XFS_BLI_STALE)
401		return;
402
403	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
404
405	/*
406	 * Free up the log item descriptor tracking the released item.
 
407	 */
 
408	xfs_trans_del_item(&bip->bli_item);
 
409
410	/*
411	 * Clear the hold flag in the buf log item if it is set.
412	 * We wouldn't want the next user of the buffer to
413	 * get confused.
414	 */
415	if (bip->bli_flags & XFS_BLI_HOLD) {
416		bip->bli_flags &= ~XFS_BLI_HOLD;
417	}
418
419	/*
420	 * Drop our reference to the buf log item.
421	 */
422	atomic_dec(&bip->bli_refcount);
423
424	/*
425	 * If the buf item is not tracking data in the log, then
426	 * we must free it before releasing the buffer back to the
427	 * free pool.  Before releasing the buffer to the free pool,
428	 * clear the transaction pointer in b_fsprivate2 to dissolve
429	 * its relation to this transaction.
430	 */
431	if (!xfs_buf_item_dirty(bip)) {
432/***
433		ASSERT(bp->b_pincount == 0);
434***/
435		ASSERT(atomic_read(&bip->bli_refcount) == 0);
436		ASSERT(!(bip->bli_item.li_flags & XFS_LI_IN_AIL));
437		ASSERT(!(bip->bli_flags & XFS_BLI_INODE_ALLOC_BUF));
438		xfs_buf_item_relse(bp);
439	}
440
441	bp->b_transp = NULL;
442	xfs_buf_relse(bp);
443}
444
445/*
446 * Mark the buffer as not needing to be unlocked when the buf item's
447 * iop_unlock() routine is called.  The buffer must already be locked
448 * and associated with the given transaction.
449 */
450/* ARGSUSED */
451void
452xfs_trans_bhold(xfs_trans_t	*tp,
453		xfs_buf_t	*bp)
 
454{
455	xfs_buf_log_item_t	*bip = bp->b_fspriv;
456
457	ASSERT(bp->b_transp == tp);
458	ASSERT(bip != NULL);
459	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
460	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
461	ASSERT(atomic_read(&bip->bli_refcount) > 0);
462
463	bip->bli_flags |= XFS_BLI_HOLD;
464	trace_xfs_trans_bhold(bip);
465}
466
467/*
468 * Cancel the previous buffer hold request made on this buffer
469 * for this transaction.
470 */
471void
472xfs_trans_bhold_release(xfs_trans_t	*tp,
473			xfs_buf_t	*bp)
 
474{
475	xfs_buf_log_item_t	*bip = bp->b_fspriv;
476
477	ASSERT(bp->b_transp == tp);
478	ASSERT(bip != NULL);
479	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
480	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
481	ASSERT(atomic_read(&bip->bli_refcount) > 0);
482	ASSERT(bip->bli_flags & XFS_BLI_HOLD);
483
484	bip->bli_flags &= ~XFS_BLI_HOLD;
485	trace_xfs_trans_bhold_release(bip);
486}
487
488/*
489 * This is called to mark bytes first through last inclusive of the given
490 * buffer as needing to be logged when the transaction is committed.
491 * The buffer must already be associated with the given transaction.
492 *
493 * First and last are numbers relative to the beginning of this buffer,
494 * so the first byte in the buffer is numbered 0 regardless of the
495 * value of b_blkno.
496 */
497void
498xfs_trans_log_buf(xfs_trans_t	*tp,
499		  xfs_buf_t	*bp,
500		  uint		first,
501		  uint		last)
502{
503	xfs_buf_log_item_t	*bip = bp->b_fspriv;
504
505	ASSERT(bp->b_transp == tp);
506	ASSERT(bip != NULL);
507	ASSERT(first <= last && last < BBTOB(bp->b_length));
508	ASSERT(bp->b_iodone == NULL ||
509	       bp->b_iodone == xfs_buf_iodone_callbacks);
510
511	/*
512	 * Mark the buffer as needing to be written out eventually,
513	 * and set its iodone function to remove the buffer's buf log
514	 * item from the AIL and free it when the buffer is flushed
515	 * to disk.  See xfs_buf_attach_iodone() for more details
516	 * on li_cb and xfs_buf_iodone_callbacks().
517	 * If we end up aborting this transaction, we trap this buffer
518	 * inside the b_bdstrat callback so that this won't get written to
519	 * disk.
520	 */
521	bp->b_flags |= XBF_DONE;
522
523	ASSERT(atomic_read(&bip->bli_refcount) > 0);
524	bp->b_iodone = xfs_buf_iodone_callbacks;
525	bip->bli_item.li_cb = xfs_buf_iodone;
526
527	trace_xfs_trans_log_buf(bip);
528
529	/*
530	 * If we invalidated the buffer within this transaction, then
531	 * cancel the invalidation now that we're dirtying the buffer
532	 * again.  There are no races with the code in xfs_buf_item_unpin(),
533	 * because we have a reference to the buffer this entire time.
534	 */
535	if (bip->bli_flags & XFS_BLI_STALE) {
536		bip->bli_flags &= ~XFS_BLI_STALE;
537		ASSERT(bp->b_flags & XBF_STALE);
538		bp->b_flags &= ~XBF_STALE;
539		bip->__bli_format.blf_flags &= ~XFS_BLF_CANCEL;
540	}
 
541
542	tp->t_flags |= XFS_TRANS_DIRTY;
543	bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
 
544
545	/*
546	 * If we have an ordered buffer we are not logging any dirty range but
547	 * it still needs to be marked dirty and that it has been logged.
548	 */
549	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
550	if (!(bip->bli_flags & XFS_BLI_ORDERED))
551		xfs_buf_item_log(bip, first, last);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
552}
553
554
555/*
556 * Invalidate a buffer that is being used within a transaction.
557 *
558 * Typically this is because the blocks in the buffer are being freed, so we
559 * need to prevent it from being written out when we're done.  Allowing it
560 * to be written again might overwrite data in the free blocks if they are
561 * reallocated to a file.
562 *
563 * We prevent the buffer from being written out by marking it stale.  We can't
564 * get rid of the buf log item at this point because the buffer may still be
565 * pinned by another transaction.  If that is the case, then we'll wait until
566 * the buffer is committed to disk for the last time (we can tell by the ref
567 * count) and free it in xfs_buf_item_unpin().  Until that happens we will
568 * keep the buffer locked so that the buffer and buf log item are not reused.
569 *
570 * We also set the XFS_BLF_CANCEL flag in the buf log format structure and log
571 * the buf item.  This will be used at recovery time to determine that copies
572 * of the buffer in the log before this should not be replayed.
573 *
574 * We mark the item descriptor and the transaction dirty so that we'll hold
575 * the buffer until after the commit.
576 *
577 * Since we're invalidating the buffer, we also clear the state about which
578 * parts of the buffer have been logged.  We also clear the flag indicating
579 * that this is an inode buffer since the data in the buffer will no longer
580 * be valid.
581 *
582 * We set the stale bit in the buffer as well since we're getting rid of it.
583 */
584void
585xfs_trans_binval(
586	xfs_trans_t	*tp,
587	xfs_buf_t	*bp)
588{
589	xfs_buf_log_item_t	*bip = bp->b_fspriv;
590	int			i;
591
592	ASSERT(bp->b_transp == tp);
593	ASSERT(bip != NULL);
594	ASSERT(atomic_read(&bip->bli_refcount) > 0);
595
596	trace_xfs_trans_binval(bip);
597
598	if (bip->bli_flags & XFS_BLI_STALE) {
599		/*
600		 * If the buffer is already invalidated, then
601		 * just return.
602		 */
603		ASSERT(bp->b_flags & XBF_STALE);
604		ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
605		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_INODE_BUF));
606		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLFT_MASK));
607		ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
608		ASSERT(bip->bli_item.li_desc->lid_flags & XFS_LID_DIRTY);
609		ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
610		return;
611	}
612
613	xfs_buf_stale(bp);
614
615	bip->bli_flags |= XFS_BLI_STALE;
616	bip->bli_flags &= ~(XFS_BLI_INODE_BUF | XFS_BLI_LOGGED | XFS_BLI_DIRTY);
617	bip->__bli_format.blf_flags &= ~XFS_BLF_INODE_BUF;
618	bip->__bli_format.blf_flags |= XFS_BLF_CANCEL;
619	bip->__bli_format.blf_flags &= ~XFS_BLFT_MASK;
620	for (i = 0; i < bip->bli_format_count; i++) {
621		memset(bip->bli_formats[i].blf_data_map, 0,
622		       (bip->bli_formats[i].blf_map_size * sizeof(uint)));
623	}
624	bip->bli_item.li_desc->lid_flags |= XFS_LID_DIRTY;
625	tp->t_flags |= XFS_TRANS_DIRTY;
626}
627
628/*
629 * This call is used to indicate that the buffer contains on-disk inodes which
630 * must be handled specially during recovery.  They require special handling
631 * because only the di_next_unlinked from the inodes in the buffer should be
632 * recovered.  The rest of the data in the buffer is logged via the inodes
633 * themselves.
634 *
635 * All we do is set the XFS_BLI_INODE_BUF flag in the items flags so it can be
636 * transferred to the buffer's log format structure so that we'll know what to
637 * do at recovery time.
638 */
639void
640xfs_trans_inode_buf(
641	xfs_trans_t	*tp,
642	xfs_buf_t	*bp)
643{
644	xfs_buf_log_item_t	*bip = bp->b_fspriv;
645
646	ASSERT(bp->b_transp == tp);
647	ASSERT(bip != NULL);
648	ASSERT(atomic_read(&bip->bli_refcount) > 0);
649
650	bip->bli_flags |= XFS_BLI_INODE_BUF;
 
651	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
652}
653
654/*
655 * This call is used to indicate that the buffer is going to
656 * be staled and was an inode buffer. This means it gets
657 * special processing during unpin - where any inodes
658 * associated with the buffer should be removed from ail.
659 * There is also special processing during recovery,
660 * any replay of the inodes in the buffer needs to be
661 * prevented as the buffer may have been reused.
662 */
663void
664xfs_trans_stale_inode_buf(
665	xfs_trans_t	*tp,
666	xfs_buf_t	*bp)
667{
668	xfs_buf_log_item_t	*bip = bp->b_fspriv;
669
670	ASSERT(bp->b_transp == tp);
671	ASSERT(bip != NULL);
672	ASSERT(atomic_read(&bip->bli_refcount) > 0);
673
674	bip->bli_flags |= XFS_BLI_STALE_INODE;
675	bip->bli_item.li_cb = xfs_buf_iodone;
676	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
677}
678
679/*
680 * Mark the buffer as being one which contains newly allocated
681 * inodes.  We need to make sure that even if this buffer is
682 * relogged as an 'inode buf' we still recover all of the inode
683 * images in the face of a crash.  This works in coordination with
684 * xfs_buf_item_committed() to ensure that the buffer remains in the
685 * AIL at its original location even after it has been relogged.
686 */
687/* ARGSUSED */
688void
689xfs_trans_inode_alloc_buf(
690	xfs_trans_t	*tp,
691	xfs_buf_t	*bp)
692{
693	xfs_buf_log_item_t	*bip = bp->b_fspriv;
694
695	ASSERT(bp->b_transp == tp);
696	ASSERT(bip != NULL);
697	ASSERT(atomic_read(&bip->bli_refcount) > 0);
698
699	bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
 
700	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
701}
702
703/*
704 * Mark the buffer as ordered for this transaction. This means
705 * that the contents of the buffer are not recorded in the transaction
706 * but it is tracked in the AIL as though it was. This allows us
707 * to record logical changes in transactions rather than the physical
708 * changes we make to the buffer without changing writeback ordering
709 * constraints of metadata buffers.
710 */
711void
712xfs_trans_ordered_buf(
713	struct xfs_trans	*tp,
714	struct xfs_buf		*bp)
715{
716	struct xfs_buf_log_item	*bip = bp->b_fspriv;
717
718	ASSERT(bp->b_transp == tp);
719	ASSERT(bip != NULL);
720	ASSERT(atomic_read(&bip->bli_refcount) > 0);
721
 
 
 
722	bip->bli_flags |= XFS_BLI_ORDERED;
723	trace_xfs_buf_item_ordered(bip);
 
 
 
 
 
 
 
724}
725
726/*
727 * Set the type of the buffer for log recovery so that it can correctly identify
728 * and hence attach the correct buffer ops to the buffer after replay.
729 */
730void
731xfs_trans_buf_set_type(
732	struct xfs_trans	*tp,
733	struct xfs_buf		*bp,
734	enum xfs_blft		type)
735{
736	struct xfs_buf_log_item	*bip = bp->b_fspriv;
737
738	if (!tp)
739		return;
740
741	ASSERT(bp->b_transp == tp);
742	ASSERT(bip != NULL);
743	ASSERT(atomic_read(&bip->bli_refcount) > 0);
744
745	xfs_blft_to_flags(&bip->__bli_format, type);
746}
747
748void
749xfs_trans_buf_copy_type(
750	struct xfs_buf		*dst_bp,
751	struct xfs_buf		*src_bp)
752{
753	struct xfs_buf_log_item	*sbip = src_bp->b_fspriv;
754	struct xfs_buf_log_item	*dbip = dst_bp->b_fspriv;
755	enum xfs_blft		type;
756
757	type = xfs_blft_from_flags(&sbip->__bli_format);
758	xfs_blft_to_flags(&dbip->__bli_format, type);
759}
760
761/*
762 * Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
763 * dquots. However, unlike in inode buffer recovery, dquot buffers get
764 * recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
765 * The only thing that makes dquot buffers different from regular
766 * buffers is that we must not replay dquot bufs when recovering
767 * if a _corresponding_ quotaoff has happened. We also have to distinguish
768 * between usr dquot bufs and grp dquot bufs, because usr and grp quotas
769 * can be turned off independently.
770 */
771/* ARGSUSED */
772void
773xfs_trans_dquot_buf(
774	xfs_trans_t	*tp,
775	xfs_buf_t	*bp,
776	uint		type)
777{
778	struct xfs_buf_log_item	*bip = bp->b_fspriv;
779
780	ASSERT(type == XFS_BLF_UDQUOT_BUF ||
781	       type == XFS_BLF_PDQUOT_BUF ||
782	       type == XFS_BLF_GDQUOT_BUF);
783
784	bip->__bli_format.blf_flags |= type;
785
786	switch (type) {
787	case XFS_BLF_UDQUOT_BUF:
788		type = XFS_BLFT_UDQUOT_BUF;
789		break;
790	case XFS_BLF_PDQUOT_BUF:
791		type = XFS_BLFT_PDQUOT_BUF;
792		break;
793	case XFS_BLF_GDQUOT_BUF:
794		type = XFS_BLFT_GDQUOT_BUF;
795		break;
796	default:
797		type = XFS_BLFT_UNKNOWN_BUF;
798		break;
799	}
800
 
801	xfs_trans_buf_set_type(tp, bp, type);
802}
v5.9
  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 */
 22STATIC struct xfs_buf *
 23xfs_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_ADDR(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 */
 60STATIC 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
 97void
 98xfs_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 */
115int
116xfs_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	xfs_buf_t		*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_FORCED_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 of this file system for the
170 * given transaction.
171 *
172 * We don't need to use incore_match() here, because the superblock
173 * buffer is a private buffer which we keep a pointer to in the
174 * mount structure.
175 */
176xfs_buf_t *
177xfs_trans_getsb(
178	xfs_trans_t		*tp,
179	struct xfs_mount	*mp)
180{
181	xfs_buf_t		*bp;
182	struct xfs_buf_log_item	*bip;
183
184	/*
185	 * Default to just trying to lock the superblock buffer
186	 * if tp is NULL.
187	 */
188	if (tp == NULL)
189		return xfs_getsb(mp);
190
191	/*
192	 * If the superblock buffer already has this transaction
193	 * pointer in its b_fsprivate2 field, then we know we already
194	 * have it locked.  In this case we just increment the lock
195	 * recursion count and return the buffer to the caller.
196	 */
197	bp = mp->m_sb_bp;
198	if (bp->b_transp == tp) {
199		bip = bp->b_log_item;
200		ASSERT(bip != NULL);
201		ASSERT(atomic_read(&bip->bli_refcount) > 0);
202		bip->bli_recur++;
203		trace_xfs_trans_getsb_recur(bip);
204		return bp;
205	}
206
207	bp = xfs_getsb(mp);
208	if (bp == NULL)
209		return NULL;
210
211	_xfs_trans_bjoin(tp, bp, 1);
212	trace_xfs_trans_getsb(bp->b_log_item);
213	return bp;
214}
215
216/*
217 * Get and lock the buffer for the caller if it is not already
218 * locked within the given transaction.  If it has not yet been
219 * read in, read it from disk. If it is already locked
220 * within the transaction and already read in, just increment its
221 * lock recursion count and return a pointer to it.
222 *
223 * If the transaction pointer is NULL, make this just a normal
224 * read_buf() call.
225 */
226int
227xfs_trans_read_buf_map(
228	struct xfs_mount	*mp,
229	struct xfs_trans	*tp,
230	struct xfs_buftarg	*target,
231	struct xfs_buf_map	*map,
232	int			nmaps,
233	xfs_buf_flags_t		flags,
234	struct xfs_buf		**bpp,
235	const struct xfs_buf_ops *ops)
236{
237	struct xfs_buf		*bp = NULL;
238	struct xfs_buf_log_item	*bip;
239	int			error;
240
241	*bpp = NULL;
242	/*
243	 * If we find the buffer in the cache with this transaction
244	 * pointer in its b_fsprivate2 field, then we know we already
245	 * have it locked.  If it is already read in we just increment
246	 * the lock recursion count and return the buffer to the caller.
247	 * If the buffer is not yet read in, then we read it in, increment
248	 * the lock recursion count, and return it to the caller.
249	 */
250	if (tp)
251		bp = xfs_trans_buf_item_match(tp, target, map, nmaps);
252	if (bp) {
253		ASSERT(xfs_buf_islocked(bp));
254		ASSERT(bp->b_transp == tp);
255		ASSERT(bp->b_log_item != NULL);
256		ASSERT(!bp->b_error);
257		ASSERT(bp->b_flags & XBF_DONE);
258
259		/*
260		 * We never locked this buf ourselves, so we shouldn't
261		 * brelse it either. Just get out.
262		 */
263		if (XFS_FORCED_SHUTDOWN(mp)) {
264			trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
265			return -EIO;
266		}
267
268		/*
269		 * Check if the caller is trying to read a buffer that is
270		 * already attached to the transaction yet has no buffer ops
271		 * assigned.  Ops are usually attached when the buffer is
272		 * attached to the transaction, or by the read caller if
273		 * special circumstances.  That didn't happen, which is not
274		 * how this is supposed to go.
275		 *
276		 * If the buffer passes verification we'll let this go, but if
277		 * not we have to shut down.  Let the transaction cleanup code
278		 * release this buffer when it kills the tranaction.
279		 */
280		ASSERT(bp->b_ops != NULL);
281		error = xfs_buf_reverify(bp, ops);
282		if (error) {
283			xfs_buf_ioerror_alert(bp, __return_address);
284
285			if (tp->t_flags & XFS_TRANS_DIRTY)
286				xfs_force_shutdown(tp->t_mountp,
287						SHUTDOWN_META_IO_ERROR);
288
289			/* bad CRC means corrupted metadata */
290			if (error == -EFSBADCRC)
291				error = -EFSCORRUPTED;
292			return error;
293		}
294
295		bip = bp->b_log_item;
296		bip->bli_recur++;
297
298		ASSERT(atomic_read(&bip->bli_refcount) > 0);
299		trace_xfs_trans_read_buf_recur(bip);
300		ASSERT(bp->b_ops != NULL || ops == NULL);
301		*bpp = bp;
302		return 0;
303	}
304
305	error = xfs_buf_read_map(target, map, nmaps, flags, &bp, ops,
306			__return_address);
307	switch (error) {
308	case 0:
309		break;
310	default:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
311		if (tp && (tp->t_flags & XFS_TRANS_DIRTY))
312			xfs_force_shutdown(tp->t_mountp, SHUTDOWN_META_IO_ERROR);
313		/* fall through */
314	case -ENOMEM:
315	case -EAGAIN:
 
 
316		return error;
317	}
318
319	if (XFS_FORCED_SHUTDOWN(mp)) {
320		xfs_buf_relse(bp);
321		trace_xfs_trans_read_buf_shut(bp, _RET_IP_);
322		return -EIO;
323	}
324
325	if (tp) {
326		_xfs_trans_bjoin(tp, bp, 1);
327		trace_xfs_trans_read_buf(bp->b_log_item);
328	}
329	ASSERT(bp->b_ops != NULL || ops == NULL);
330	*bpp = bp;
331	return 0;
332
333}
334
335/* Has this buffer been dirtied by anyone? */
336bool
337xfs_trans_buf_is_dirty(
338	struct xfs_buf		*bp)
339{
340	struct xfs_buf_log_item	*bip = bp->b_log_item;
341
342	if (!bip)
343		return false;
344	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
345	return test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
346}
347
348/*
349 * Release a buffer previously joined to the transaction. If the buffer is
350 * modified within this transaction, decrement the recursion count but do not
351 * release the buffer even if the count goes to 0. If the buffer is not modified
352 * within the transaction, decrement the recursion count and release the buffer
353 * if the recursion count goes to 0.
 
 
354 *
355 * If the buffer is to be released and it was not already dirty before this
356 * transaction began, then also free the buf_log_item associated with it.
357 *
358 * If the transaction pointer is NULL, this is a normal xfs_buf_relse() call.
 
359 */
360void
361xfs_trans_brelse(
362	struct xfs_trans	*tp,
363	struct xfs_buf		*bp)
364{
365	struct xfs_buf_log_item	*bip = bp->b_log_item;
366
367	ASSERT(bp->b_transp == tp);
368
369	if (!tp) {
 
 
370		xfs_buf_relse(bp);
371		return;
372	}
373
374	trace_xfs_trans_brelse(bip);
 
375	ASSERT(bip->bli_item.li_type == XFS_LI_BUF);
 
 
376	ASSERT(atomic_read(&bip->bli_refcount) > 0);
377
 
 
378	/*
379	 * If the release is for a recursive lookup, then decrement the count
380	 * and return.
381	 */
382	if (bip->bli_recur > 0) {
383		bip->bli_recur--;
384		return;
385	}
386
387	/*
388	 * If the buffer is invalidated or dirty in this transaction, we can't
389	 * release it until we commit.
390	 */
391	if (test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags))
392		return;
 
 
 
 
 
 
 
393	if (bip->bli_flags & XFS_BLI_STALE)
394		return;
395
 
 
396	/*
397	 * Unlink the log item from the transaction and clear the hold flag, if
398	 * set. We wouldn't want the next user of the buffer to get confused.
399	 */
400	ASSERT(!(bip->bli_flags & XFS_BLI_LOGGED));
401	xfs_trans_del_item(&bip->bli_item);
402	bip->bli_flags &= ~XFS_BLI_HOLD;
403
404	/* drop the reference to the bli */
405	xfs_buf_item_put(bip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
406
407	bp->b_transp = NULL;
408	xfs_buf_relse(bp);
409}
410
411/*
412 * Mark the buffer as not needing to be unlocked when the buf item's
413 * iop_committing() routine is called.  The buffer must already be locked
414 * and associated with the given transaction.
415 */
416/* ARGSUSED */
417void
418xfs_trans_bhold(
419	xfs_trans_t		*tp,
420	xfs_buf_t		*bp)
421{
422	struct xfs_buf_log_item	*bip = bp->b_log_item;
423
424	ASSERT(bp->b_transp == tp);
425	ASSERT(bip != NULL);
426	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
427	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
428	ASSERT(atomic_read(&bip->bli_refcount) > 0);
429
430	bip->bli_flags |= XFS_BLI_HOLD;
431	trace_xfs_trans_bhold(bip);
432}
433
434/*
435 * Cancel the previous buffer hold request made on this buffer
436 * for this transaction.
437 */
438void
439xfs_trans_bhold_release(
440	xfs_trans_t		*tp,
441	xfs_buf_t		*bp)
442{
443	struct xfs_buf_log_item	*bip = bp->b_log_item;
444
445	ASSERT(bp->b_transp == tp);
446	ASSERT(bip != NULL);
447	ASSERT(!(bip->bli_flags & XFS_BLI_STALE));
448	ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_CANCEL));
449	ASSERT(atomic_read(&bip->bli_refcount) > 0);
450	ASSERT(bip->bli_flags & XFS_BLI_HOLD);
451
452	bip->bli_flags &= ~XFS_BLI_HOLD;
453	trace_xfs_trans_bhold_release(bip);
454}
455
456/*
457 * Mark a buffer dirty in the transaction.
 
 
 
 
 
 
458 */
459void
460xfs_trans_dirty_buf(
461	struct xfs_trans	*tp,
462	struct xfs_buf		*bp)
 
463{
464	struct xfs_buf_log_item	*bip = bp->b_log_item;
465
466	ASSERT(bp->b_transp == tp);
467	ASSERT(bip != NULL);
 
 
 
468
469	/*
470	 * Mark the buffer as needing to be written out eventually,
471	 * and set its iodone function to remove the buffer's buf log
472	 * item from the AIL and free it when the buffer is flushed
473	 * to disk.
 
 
 
 
474	 */
475	bp->b_flags |= XBF_DONE;
476
477	ASSERT(atomic_read(&bip->bli_refcount) > 0);
 
 
 
 
478
479	/*
480	 * If we invalidated the buffer within this transaction, then
481	 * cancel the invalidation now that we're dirtying the buffer
482	 * again.  There are no races with the code in xfs_buf_item_unpin(),
483	 * because we have a reference to the buffer this entire time.
484	 */
485	if (bip->bli_flags & XFS_BLI_STALE) {
486		bip->bli_flags &= ~XFS_BLI_STALE;
487		ASSERT(bp->b_flags & XBF_STALE);
488		bp->b_flags &= ~XBF_STALE;
489		bip->__bli_format.blf_flags &= ~XFS_BLF_CANCEL;
490	}
491	bip->bli_flags |= XFS_BLI_DIRTY | XFS_BLI_LOGGED;
492
493	tp->t_flags |= XFS_TRANS_DIRTY;
494	set_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
495}
496
497/*
498 * This is called to mark bytes first through last inclusive of the given
499 * buffer as needing to be logged when the transaction is committed.
500 * The buffer must already be associated with the given transaction.
501 *
502 * First and last are numbers relative to the beginning of this buffer,
503 * so the first byte in the buffer is numbered 0 regardless of the
504 * value of b_blkno.
505 */
506void
507xfs_trans_log_buf(
508	struct xfs_trans	*tp,
509	struct xfs_buf		*bp,
510	uint			first,
511	uint			last)
512{
513	struct xfs_buf_log_item	*bip = bp->b_log_item;
514
515	ASSERT(first <= last && last < BBTOB(bp->b_length));
516	ASSERT(!(bip->bli_flags & XFS_BLI_ORDERED));
517
518	xfs_trans_dirty_buf(tp, bp);
519
520	trace_xfs_trans_log_buf(bip);
521	xfs_buf_item_log(bip, first, last);
522}
523
524
525/*
526 * Invalidate a buffer that is being used within a transaction.
527 *
528 * Typically this is because the blocks in the buffer are being freed, so we
529 * need to prevent it from being written out when we're done.  Allowing it
530 * to be written again might overwrite data in the free blocks if they are
531 * reallocated to a file.
532 *
533 * We prevent the buffer from being written out by marking it stale.  We can't
534 * get rid of the buf log item at this point because the buffer may still be
535 * pinned by another transaction.  If that is the case, then we'll wait until
536 * the buffer is committed to disk for the last time (we can tell by the ref
537 * count) and free it in xfs_buf_item_unpin().  Until that happens we will
538 * keep the buffer locked so that the buffer and buf log item are not reused.
539 *
540 * We also set the XFS_BLF_CANCEL flag in the buf log format structure and log
541 * the buf item.  This will be used at recovery time to determine that copies
542 * of the buffer in the log before this should not be replayed.
543 *
544 * We mark the item descriptor and the transaction dirty so that we'll hold
545 * the buffer until after the commit.
546 *
547 * Since we're invalidating the buffer, we also clear the state about which
548 * parts of the buffer have been logged.  We also clear the flag indicating
549 * that this is an inode buffer since the data in the buffer will no longer
550 * be valid.
551 *
552 * We set the stale bit in the buffer as well since we're getting rid of it.
553 */
554void
555xfs_trans_binval(
556	xfs_trans_t		*tp,
557	xfs_buf_t		*bp)
558{
559	struct xfs_buf_log_item	*bip = bp->b_log_item;
560	int			i;
561
562	ASSERT(bp->b_transp == tp);
563	ASSERT(bip != NULL);
564	ASSERT(atomic_read(&bip->bli_refcount) > 0);
565
566	trace_xfs_trans_binval(bip);
567
568	if (bip->bli_flags & XFS_BLI_STALE) {
569		/*
570		 * If the buffer is already invalidated, then
571		 * just return.
572		 */
573		ASSERT(bp->b_flags & XBF_STALE);
574		ASSERT(!(bip->bli_flags & (XFS_BLI_LOGGED | XFS_BLI_DIRTY)));
575		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLF_INODE_BUF));
576		ASSERT(!(bip->__bli_format.blf_flags & XFS_BLFT_MASK));
577		ASSERT(bip->__bli_format.blf_flags & XFS_BLF_CANCEL);
578		ASSERT(test_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags));
579		ASSERT(tp->t_flags & XFS_TRANS_DIRTY);
580		return;
581	}
582
583	xfs_buf_stale(bp);
584
585	bip->bli_flags |= XFS_BLI_STALE;
586	bip->bli_flags &= ~(XFS_BLI_INODE_BUF | XFS_BLI_LOGGED | XFS_BLI_DIRTY);
587	bip->__bli_format.blf_flags &= ~XFS_BLF_INODE_BUF;
588	bip->__bli_format.blf_flags |= XFS_BLF_CANCEL;
589	bip->__bli_format.blf_flags &= ~XFS_BLFT_MASK;
590	for (i = 0; i < bip->bli_format_count; i++) {
591		memset(bip->bli_formats[i].blf_data_map, 0,
592		       (bip->bli_formats[i].blf_map_size * sizeof(uint)));
593	}
594	set_bit(XFS_LI_DIRTY, &bip->bli_item.li_flags);
595	tp->t_flags |= XFS_TRANS_DIRTY;
596}
597
598/*
599 * This call is used to indicate that the buffer contains on-disk inodes which
600 * must be handled specially during recovery.  They require special handling
601 * because only the di_next_unlinked from the inodes in the buffer should be
602 * recovered.  The rest of the data in the buffer is logged via the inodes
603 * themselves.
604 *
605 * All we do is set the XFS_BLI_INODE_BUF flag in the items flags so it can be
606 * transferred to the buffer's log format structure so that we'll know what to
607 * do at recovery time.
608 */
609void
610xfs_trans_inode_buf(
611	xfs_trans_t		*tp,
612	xfs_buf_t		*bp)
613{
614	struct xfs_buf_log_item	*bip = bp->b_log_item;
615
616	ASSERT(bp->b_transp == tp);
617	ASSERT(bip != NULL);
618	ASSERT(atomic_read(&bip->bli_refcount) > 0);
619
620	bip->bli_flags |= XFS_BLI_INODE_BUF;
621	bp->b_flags |= _XBF_INODES;
622	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
623}
624
625/*
626 * This call is used to indicate that the buffer is going to
627 * be staled and was an inode buffer. This means it gets
628 * special processing during unpin - where any inodes
629 * associated with the buffer should be removed from ail.
630 * There is also special processing during recovery,
631 * any replay of the inodes in the buffer needs to be
632 * prevented as the buffer may have been reused.
633 */
634void
635xfs_trans_stale_inode_buf(
636	xfs_trans_t		*tp,
637	xfs_buf_t		*bp)
638{
639	struct xfs_buf_log_item	*bip = bp->b_log_item;
640
641	ASSERT(bp->b_transp == tp);
642	ASSERT(bip != NULL);
643	ASSERT(atomic_read(&bip->bli_refcount) > 0);
644
645	bip->bli_flags |= XFS_BLI_STALE_INODE;
646	bp->b_flags |= _XBF_INODES;
647	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
648}
649
650/*
651 * Mark the buffer as being one which contains newly allocated
652 * inodes.  We need to make sure that even if this buffer is
653 * relogged as an 'inode buf' we still recover all of the inode
654 * images in the face of a crash.  This works in coordination with
655 * xfs_buf_item_committed() to ensure that the buffer remains in the
656 * AIL at its original location even after it has been relogged.
657 */
658/* ARGSUSED */
659void
660xfs_trans_inode_alloc_buf(
661	xfs_trans_t		*tp,
662	xfs_buf_t		*bp)
663{
664	struct xfs_buf_log_item	*bip = bp->b_log_item;
665
666	ASSERT(bp->b_transp == tp);
667	ASSERT(bip != NULL);
668	ASSERT(atomic_read(&bip->bli_refcount) > 0);
669
670	bip->bli_flags |= XFS_BLI_INODE_ALLOC_BUF;
671	bp->b_flags |= _XBF_INODES;
672	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DINO_BUF);
673}
674
675/*
676 * Mark the buffer as ordered for this transaction. This means that the contents
677 * of the buffer are not recorded in the transaction but it is tracked in the
678 * AIL as though it was. This allows us to record logical changes in
679 * transactions rather than the physical changes we make to the buffer without
680 * changing writeback ordering constraints of metadata buffers.
 
681 */
682bool
683xfs_trans_ordered_buf(
684	struct xfs_trans	*tp,
685	struct xfs_buf		*bp)
686{
687	struct xfs_buf_log_item	*bip = bp->b_log_item;
688
689	ASSERT(bp->b_transp == tp);
690	ASSERT(bip != NULL);
691	ASSERT(atomic_read(&bip->bli_refcount) > 0);
692
693	if (xfs_buf_item_dirty_format(bip))
694		return false;
695
696	bip->bli_flags |= XFS_BLI_ORDERED;
697	trace_xfs_buf_item_ordered(bip);
698
699	/*
700	 * We don't log a dirty range of an ordered buffer but it still needs
701	 * to be marked dirty and that it has been logged.
702	 */
703	xfs_trans_dirty_buf(tp, bp);
704	return true;
705}
706
707/*
708 * Set the type of the buffer for log recovery so that it can correctly identify
709 * and hence attach the correct buffer ops to the buffer after replay.
710 */
711void
712xfs_trans_buf_set_type(
713	struct xfs_trans	*tp,
714	struct xfs_buf		*bp,
715	enum xfs_blft		type)
716{
717	struct xfs_buf_log_item	*bip = bp->b_log_item;
718
719	if (!tp)
720		return;
721
722	ASSERT(bp->b_transp == tp);
723	ASSERT(bip != NULL);
724	ASSERT(atomic_read(&bip->bli_refcount) > 0);
725
726	xfs_blft_to_flags(&bip->__bli_format, type);
727}
728
729void
730xfs_trans_buf_copy_type(
731	struct xfs_buf		*dst_bp,
732	struct xfs_buf		*src_bp)
733{
734	struct xfs_buf_log_item	*sbip = src_bp->b_log_item;
735	struct xfs_buf_log_item	*dbip = dst_bp->b_log_item;
736	enum xfs_blft		type;
737
738	type = xfs_blft_from_flags(&sbip->__bli_format);
739	xfs_blft_to_flags(&dbip->__bli_format, type);
740}
741
742/*
743 * Similar to xfs_trans_inode_buf(), this marks the buffer as a cluster of
744 * dquots. However, unlike in inode buffer recovery, dquot buffers get
745 * recovered in their entirety. (Hence, no XFS_BLI_DQUOT_ALLOC_BUF flag).
746 * The only thing that makes dquot buffers different from regular
747 * buffers is that we must not replay dquot bufs when recovering
748 * if a _corresponding_ quotaoff has happened. We also have to distinguish
749 * between usr dquot bufs and grp dquot bufs, because usr and grp quotas
750 * can be turned off independently.
751 */
752/* ARGSUSED */
753void
754xfs_trans_dquot_buf(
755	xfs_trans_t		*tp,
756	xfs_buf_t		*bp,
757	uint			type)
758{
759	struct xfs_buf_log_item	*bip = bp->b_log_item;
760
761	ASSERT(type == XFS_BLF_UDQUOT_BUF ||
762	       type == XFS_BLF_PDQUOT_BUF ||
763	       type == XFS_BLF_GDQUOT_BUF);
764
765	bip->__bli_format.blf_flags |= type;
766
767	switch (type) {
768	case XFS_BLF_UDQUOT_BUF:
769		type = XFS_BLFT_UDQUOT_BUF;
770		break;
771	case XFS_BLF_PDQUOT_BUF:
772		type = XFS_BLFT_PDQUOT_BUF;
773		break;
774	case XFS_BLF_GDQUOT_BUF:
775		type = XFS_BLFT_GDQUOT_BUF;
776		break;
777	default:
778		type = XFS_BLFT_UNKNOWN_BUF;
779		break;
780	}
781
782	bp->b_flags |= _XBF_DQUOTS;
783	xfs_trans_buf_set_type(tp, bp, type);
784}