xref: /linux/fs/xfs/xfs_trans.c (revision 0e2b2a76278153d1ac312b0691cb65dabb9aef3e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
4  * Copyright (C) 2010 Red Hat, Inc.
5  * All Rights Reserved.
6  */
7 #include "xfs.h"
8 #include "xfs_fs.h"
9 #include "xfs_shared.h"
10 #include "xfs_format.h"
11 #include "xfs_log_format.h"
12 #include "xfs_trans_resv.h"
13 #include "xfs_mount.h"
14 #include "xfs_extent_busy.h"
15 #include "xfs_quota.h"
16 #include "xfs_trans.h"
17 #include "xfs_trans_priv.h"
18 #include "xfs_log.h"
19 #include "xfs_log_priv.h"
20 #include "xfs_trace.h"
21 #include "xfs_error.h"
22 #include "xfs_defer.h"
23 #include "xfs_inode.h"
24 #include "xfs_dquot_item.h"
25 #include "xfs_dquot.h"
26 #include "xfs_icache.h"
27 
28 struct kmem_cache	*xfs_trans_cache;
29 
30 #if defined(CONFIG_TRACEPOINTS)
31 static void
32 xfs_trans_trace_reservations(
33 	struct xfs_mount	*mp)
34 {
35 	struct xfs_trans_res	*res;
36 	struct xfs_trans_res	*end_res;
37 	int			i;
38 
39 	res = (struct xfs_trans_res *)M_RES(mp);
40 	end_res = (struct xfs_trans_res *)(M_RES(mp) + 1);
41 	for (i = 0; res < end_res; i++, res++)
42 		trace_xfs_trans_resv_calc(mp, i, res);
43 }
44 #else
45 # define xfs_trans_trace_reservations(mp)
46 #endif
47 
48 /*
49  * Initialize the precomputed transaction reservation values
50  * in the mount structure.
51  */
52 void
53 xfs_trans_init(
54 	struct xfs_mount	*mp)
55 {
56 	xfs_trans_resv_calc(mp, M_RES(mp));
57 	xfs_trans_trace_reservations(mp);
58 }
59 
60 /*
61  * Free the transaction structure.  If there is more clean up
62  * to do when the structure is freed, add it here.
63  */
64 STATIC void
65 xfs_trans_free(
66 	struct xfs_trans	*tp)
67 {
68 	xfs_extent_busy_sort(&tp->t_busy);
69 	xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false);
70 
71 	trace_xfs_trans_free(tp, _RET_IP_);
72 	xfs_trans_clear_context(tp);
73 	if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT))
74 		sb_end_intwrite(tp->t_mountp->m_super);
75 	xfs_trans_free_dqinfo(tp);
76 	kmem_cache_free(xfs_trans_cache, tp);
77 }
78 
79 /*
80  * This is called to create a new transaction which will share the
81  * permanent log reservation of the given transaction.  The remaining
82  * unused block and rt extent reservations are also inherited.  This
83  * implies that the original transaction is no longer allowed to allocate
84  * blocks.  Locks and log items, however, are no inherited.  They must
85  * be added to the new transaction explicitly.
86  */
87 STATIC struct xfs_trans *
88 xfs_trans_dup(
89 	struct xfs_trans	*tp)
90 {
91 	struct xfs_trans	*ntp;
92 
93 	trace_xfs_trans_dup(tp, _RET_IP_);
94 
95 	ntp = kmem_cache_zalloc(xfs_trans_cache, GFP_KERNEL | __GFP_NOFAIL);
96 
97 	/*
98 	 * Initialize the new transaction structure.
99 	 */
100 	ntp->t_magic = XFS_TRANS_HEADER_MAGIC;
101 	ntp->t_mountp = tp->t_mountp;
102 	INIT_LIST_HEAD(&ntp->t_items);
103 	INIT_LIST_HEAD(&ntp->t_busy);
104 	INIT_LIST_HEAD(&ntp->t_dfops);
105 	ntp->t_highest_agno = NULLAGNUMBER;
106 
107 	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
108 	ASSERT(tp->t_ticket != NULL);
109 
110 	ntp->t_flags = XFS_TRANS_PERM_LOG_RES |
111 		       (tp->t_flags & XFS_TRANS_RESERVE) |
112 		       (tp->t_flags & XFS_TRANS_NO_WRITECOUNT) |
113 		       (tp->t_flags & XFS_TRANS_RES_FDBLKS);
114 	/* We gave our writer reference to the new transaction */
115 	tp->t_flags |= XFS_TRANS_NO_WRITECOUNT;
116 	ntp->t_ticket = xfs_log_ticket_get(tp->t_ticket);
117 
118 	ASSERT(tp->t_blk_res >= tp->t_blk_res_used);
119 	ntp->t_blk_res = tp->t_blk_res - tp->t_blk_res_used;
120 	tp->t_blk_res = tp->t_blk_res_used;
121 
122 	ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used;
123 	tp->t_rtx_res = tp->t_rtx_res_used;
124 
125 	xfs_trans_switch_context(tp, ntp);
126 
127 	/* move deferred ops over to the new tp */
128 	xfs_defer_move(ntp, tp);
129 
130 	xfs_trans_dup_dqinfo(tp, ntp);
131 	return ntp;
132 }
133 
134 /*
135  * This is called to reserve free disk blocks and log space for the
136  * given transaction.  This must be done before allocating any resources
137  * within the transaction.
138  *
139  * This will return ENOSPC if there are not enough blocks available.
140  * It will sleep waiting for available log space.
141  * The only valid value for the flags parameter is XFS_RES_LOG_PERM, which
142  * is used by long running transactions.  If any one of the reservations
143  * fails then they will all be backed out.
144  *
145  * This does not do quota reservations. That typically is done by the
146  * caller afterwards.
147  */
148 static int
149 xfs_trans_reserve(
150 	struct xfs_trans	*tp,
151 	struct xfs_trans_res	*resp,
152 	uint			blocks,
153 	uint			rtextents)
154 {
155 	struct xfs_mount	*mp = tp->t_mountp;
156 	int			error = 0;
157 	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
158 
159 	/*
160 	 * Attempt to reserve the needed disk blocks by decrementing
161 	 * the number needed from the number available.  This will
162 	 * fail if the count would go below zero.
163 	 */
164 	if (blocks > 0) {
165 		error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd);
166 		if (error != 0)
167 			return -ENOSPC;
168 		tp->t_blk_res += blocks;
169 	}
170 
171 	/*
172 	 * Reserve the log space needed for this transaction.
173 	 */
174 	if (resp->tr_logres > 0) {
175 		bool	permanent = false;
176 
177 		ASSERT(tp->t_log_res == 0 ||
178 		       tp->t_log_res == resp->tr_logres);
179 		ASSERT(tp->t_log_count == 0 ||
180 		       tp->t_log_count == resp->tr_logcount);
181 
182 		if (resp->tr_logflags & XFS_TRANS_PERM_LOG_RES) {
183 			tp->t_flags |= XFS_TRANS_PERM_LOG_RES;
184 			permanent = true;
185 		} else {
186 			ASSERT(tp->t_ticket == NULL);
187 			ASSERT(!(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
188 		}
189 
190 		if (tp->t_ticket != NULL) {
191 			ASSERT(resp->tr_logflags & XFS_TRANS_PERM_LOG_RES);
192 			error = xfs_log_regrant(mp, tp->t_ticket);
193 		} else {
194 			error = xfs_log_reserve(mp, resp->tr_logres,
195 						resp->tr_logcount,
196 						&tp->t_ticket, permanent);
197 		}
198 
199 		if (error)
200 			goto undo_blocks;
201 
202 		tp->t_log_res = resp->tr_logres;
203 		tp->t_log_count = resp->tr_logcount;
204 	}
205 
206 	/*
207 	 * Attempt to reserve the needed realtime extents by decrementing
208 	 * the number needed from the number available.  This will
209 	 * fail if the count would go below zero.
210 	 */
211 	if (rtextents > 0) {
212 		error = xfs_mod_frextents(mp, -((int64_t)rtextents));
213 		if (error) {
214 			error = -ENOSPC;
215 			goto undo_log;
216 		}
217 		tp->t_rtx_res += rtextents;
218 	}
219 
220 	return 0;
221 
222 	/*
223 	 * Error cases jump to one of these labels to undo any
224 	 * reservations which have already been performed.
225 	 */
226 undo_log:
227 	if (resp->tr_logres > 0) {
228 		xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket);
229 		tp->t_ticket = NULL;
230 		tp->t_log_res = 0;
231 		tp->t_flags &= ~XFS_TRANS_PERM_LOG_RES;
232 	}
233 
234 undo_blocks:
235 	if (blocks > 0) {
236 		xfs_mod_fdblocks(mp, (int64_t)blocks, rsvd);
237 		tp->t_blk_res = 0;
238 	}
239 	return error;
240 }
241 
242 int
243 xfs_trans_alloc(
244 	struct xfs_mount	*mp,
245 	struct xfs_trans_res	*resp,
246 	uint			blocks,
247 	uint			rtextents,
248 	uint			flags,
249 	struct xfs_trans	**tpp)
250 {
251 	struct xfs_trans	*tp;
252 	bool			want_retry = true;
253 	int			error;
254 
255 	/*
256 	 * Allocate the handle before we do our freeze accounting and setting up
257 	 * GFP_NOFS allocation context so that we avoid lockdep false positives
258 	 * by doing GFP_KERNEL allocations inside sb_start_intwrite().
259 	 */
260 retry:
261 	tp = kmem_cache_zalloc(xfs_trans_cache, GFP_KERNEL | __GFP_NOFAIL);
262 	if (!(flags & XFS_TRANS_NO_WRITECOUNT))
263 		sb_start_intwrite(mp->m_super);
264 	xfs_trans_set_context(tp);
265 
266 	/*
267 	 * Zero-reservation ("empty") transactions can't modify anything, so
268 	 * they're allowed to run while we're frozen.
269 	 */
270 	WARN_ON(resp->tr_logres > 0 &&
271 		mp->m_super->s_writers.frozen == SB_FREEZE_COMPLETE);
272 	ASSERT(!(flags & XFS_TRANS_RES_FDBLKS) ||
273 	       xfs_has_lazysbcount(mp));
274 
275 	tp->t_magic = XFS_TRANS_HEADER_MAGIC;
276 	tp->t_flags = flags;
277 	tp->t_mountp = mp;
278 	INIT_LIST_HEAD(&tp->t_items);
279 	INIT_LIST_HEAD(&tp->t_busy);
280 	INIT_LIST_HEAD(&tp->t_dfops);
281 	tp->t_highest_agno = NULLAGNUMBER;
282 
283 	error = xfs_trans_reserve(tp, resp, blocks, rtextents);
284 	if (error == -ENOSPC && want_retry) {
285 		xfs_trans_cancel(tp);
286 
287 		/*
288 		 * We weren't able to reserve enough space for the transaction.
289 		 * Flush the other speculative space allocations to free space.
290 		 * Do not perform a synchronous scan because callers can hold
291 		 * other locks.
292 		 */
293 		error = xfs_blockgc_flush_all(mp);
294 		if (error)
295 			return error;
296 		want_retry = false;
297 		goto retry;
298 	}
299 	if (error) {
300 		xfs_trans_cancel(tp);
301 		return error;
302 	}
303 
304 	trace_xfs_trans_alloc(tp, _RET_IP_);
305 
306 	*tpp = tp;
307 	return 0;
308 }
309 
310 /*
311  * Create an empty transaction with no reservation.  This is a defensive
312  * mechanism for routines that query metadata without actually modifying them --
313  * if the metadata being queried is somehow cross-linked (think a btree block
314  * pointer that points higher in the tree), we risk deadlock.  However, blocks
315  * grabbed as part of a transaction can be re-grabbed.  The verifiers will
316  * notice the corrupt block and the operation will fail back to userspace
317  * without deadlocking.
318  *
319  * Note the zero-length reservation; this transaction MUST be cancelled without
320  * any dirty data.
321  *
322  * Callers should obtain freeze protection to avoid a conflict with fs freezing
323  * where we can be grabbing buffers at the same time that freeze is trying to
324  * drain the buffer LRU list.
325  */
326 int
327 xfs_trans_alloc_empty(
328 	struct xfs_mount		*mp,
329 	struct xfs_trans		**tpp)
330 {
331 	struct xfs_trans_res		resv = {0};
332 
333 	return xfs_trans_alloc(mp, &resv, 0, 0, XFS_TRANS_NO_WRITECOUNT, tpp);
334 }
335 
336 /*
337  * Record the indicated change to the given field for application
338  * to the file system's superblock when the transaction commits.
339  * For now, just store the change in the transaction structure.
340  *
341  * Mark the transaction structure to indicate that the superblock
342  * needs to be updated before committing.
343  *
344  * Because we may not be keeping track of allocated/free inodes and
345  * used filesystem blocks in the superblock, we do not mark the
346  * superblock dirty in this transaction if we modify these fields.
347  * We still need to update the transaction deltas so that they get
348  * applied to the incore superblock, but we don't want them to
349  * cause the superblock to get locked and logged if these are the
350  * only fields in the superblock that the transaction modifies.
351  */
352 void
353 xfs_trans_mod_sb(
354 	xfs_trans_t	*tp,
355 	uint		field,
356 	int64_t		delta)
357 {
358 	uint32_t	flags = (XFS_TRANS_DIRTY|XFS_TRANS_SB_DIRTY);
359 	xfs_mount_t	*mp = tp->t_mountp;
360 
361 	switch (field) {
362 	case XFS_TRANS_SB_ICOUNT:
363 		tp->t_icount_delta += delta;
364 		if (xfs_has_lazysbcount(mp))
365 			flags &= ~XFS_TRANS_SB_DIRTY;
366 		break;
367 	case XFS_TRANS_SB_IFREE:
368 		tp->t_ifree_delta += delta;
369 		if (xfs_has_lazysbcount(mp))
370 			flags &= ~XFS_TRANS_SB_DIRTY;
371 		break;
372 	case XFS_TRANS_SB_FDBLOCKS:
373 		/*
374 		 * Track the number of blocks allocated in the transaction.
375 		 * Make sure it does not exceed the number reserved. If so,
376 		 * shutdown as this can lead to accounting inconsistency.
377 		 */
378 		if (delta < 0) {
379 			tp->t_blk_res_used += (uint)-delta;
380 			if (tp->t_blk_res_used > tp->t_blk_res)
381 				xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
382 		} else if (delta > 0 && (tp->t_flags & XFS_TRANS_RES_FDBLKS)) {
383 			int64_t	blkres_delta;
384 
385 			/*
386 			 * Return freed blocks directly to the reservation
387 			 * instead of the global pool, being careful not to
388 			 * overflow the trans counter. This is used to preserve
389 			 * reservation across chains of transaction rolls that
390 			 * repeatedly free and allocate blocks.
391 			 */
392 			blkres_delta = min_t(int64_t, delta,
393 					     UINT_MAX - tp->t_blk_res);
394 			tp->t_blk_res += blkres_delta;
395 			delta -= blkres_delta;
396 		}
397 		tp->t_fdblocks_delta += delta;
398 		if (xfs_has_lazysbcount(mp))
399 			flags &= ~XFS_TRANS_SB_DIRTY;
400 		break;
401 	case XFS_TRANS_SB_RES_FDBLOCKS:
402 		/*
403 		 * The allocation has already been applied to the
404 		 * in-core superblock's counter.  This should only
405 		 * be applied to the on-disk superblock.
406 		 */
407 		tp->t_res_fdblocks_delta += delta;
408 		if (xfs_has_lazysbcount(mp))
409 			flags &= ~XFS_TRANS_SB_DIRTY;
410 		break;
411 	case XFS_TRANS_SB_FREXTENTS:
412 		/*
413 		 * Track the number of blocks allocated in the
414 		 * transaction.  Make sure it does not exceed the
415 		 * number reserved.
416 		 */
417 		if (delta < 0) {
418 			tp->t_rtx_res_used += (uint)-delta;
419 			ASSERT(tp->t_rtx_res_used <= tp->t_rtx_res);
420 		}
421 		tp->t_frextents_delta += delta;
422 		break;
423 	case XFS_TRANS_SB_RES_FREXTENTS:
424 		/*
425 		 * The allocation has already been applied to the
426 		 * in-core superblock's counter.  This should only
427 		 * be applied to the on-disk superblock.
428 		 */
429 		ASSERT(delta < 0);
430 		tp->t_res_frextents_delta += delta;
431 		break;
432 	case XFS_TRANS_SB_DBLOCKS:
433 		tp->t_dblocks_delta += delta;
434 		break;
435 	case XFS_TRANS_SB_AGCOUNT:
436 		ASSERT(delta > 0);
437 		tp->t_agcount_delta += delta;
438 		break;
439 	case XFS_TRANS_SB_IMAXPCT:
440 		tp->t_imaxpct_delta += delta;
441 		break;
442 	case XFS_TRANS_SB_REXTSIZE:
443 		tp->t_rextsize_delta += delta;
444 		break;
445 	case XFS_TRANS_SB_RBMBLOCKS:
446 		tp->t_rbmblocks_delta += delta;
447 		break;
448 	case XFS_TRANS_SB_RBLOCKS:
449 		tp->t_rblocks_delta += delta;
450 		break;
451 	case XFS_TRANS_SB_REXTENTS:
452 		tp->t_rextents_delta += delta;
453 		break;
454 	case XFS_TRANS_SB_REXTSLOG:
455 		tp->t_rextslog_delta += delta;
456 		break;
457 	default:
458 		ASSERT(0);
459 		return;
460 	}
461 
462 	tp->t_flags |= flags;
463 }
464 
465 /*
466  * xfs_trans_apply_sb_deltas() is called from the commit code
467  * to bring the superblock buffer into the current transaction
468  * and modify it as requested by earlier calls to xfs_trans_mod_sb().
469  *
470  * For now we just look at each field allowed to change and change
471  * it if necessary.
472  */
473 STATIC void
474 xfs_trans_apply_sb_deltas(
475 	xfs_trans_t	*tp)
476 {
477 	struct xfs_dsb	*sbp;
478 	struct xfs_buf	*bp;
479 	int		whole = 0;
480 
481 	bp = xfs_trans_getsb(tp);
482 	sbp = bp->b_addr;
483 
484 	/*
485 	 * Only update the superblock counters if we are logging them
486 	 */
487 	if (!xfs_has_lazysbcount((tp->t_mountp))) {
488 		if (tp->t_icount_delta)
489 			be64_add_cpu(&sbp->sb_icount, tp->t_icount_delta);
490 		if (tp->t_ifree_delta)
491 			be64_add_cpu(&sbp->sb_ifree, tp->t_ifree_delta);
492 		if (tp->t_fdblocks_delta)
493 			be64_add_cpu(&sbp->sb_fdblocks, tp->t_fdblocks_delta);
494 		if (tp->t_res_fdblocks_delta)
495 			be64_add_cpu(&sbp->sb_fdblocks, tp->t_res_fdblocks_delta);
496 	}
497 
498 	/*
499 	 * Updating frextents requires careful handling because it does not
500 	 * behave like the lazysb counters because we cannot rely on log
501 	 * recovery in older kenels to recompute the value from the rtbitmap.
502 	 * This means that the ondisk frextents must be consistent with the
503 	 * rtbitmap.
504 	 *
505 	 * Therefore, log the frextents change to the ondisk superblock and
506 	 * update the incore superblock so that future calls to xfs_log_sb
507 	 * write the correct value ondisk.
508 	 *
509 	 * Don't touch m_frextents because it includes incore reservations,
510 	 * and those are handled by the unreserve function.
511 	 */
512 	if (tp->t_frextents_delta || tp->t_res_frextents_delta) {
513 		struct xfs_mount	*mp = tp->t_mountp;
514 		int64_t			rtxdelta;
515 
516 		rtxdelta = tp->t_frextents_delta + tp->t_res_frextents_delta;
517 
518 		spin_lock(&mp->m_sb_lock);
519 		be64_add_cpu(&sbp->sb_frextents, rtxdelta);
520 		mp->m_sb.sb_frextents += rtxdelta;
521 		spin_unlock(&mp->m_sb_lock);
522 	}
523 
524 	if (tp->t_dblocks_delta) {
525 		be64_add_cpu(&sbp->sb_dblocks, tp->t_dblocks_delta);
526 		whole = 1;
527 	}
528 	if (tp->t_agcount_delta) {
529 		be32_add_cpu(&sbp->sb_agcount, tp->t_agcount_delta);
530 		whole = 1;
531 	}
532 	if (tp->t_imaxpct_delta) {
533 		sbp->sb_imax_pct += tp->t_imaxpct_delta;
534 		whole = 1;
535 	}
536 	if (tp->t_rextsize_delta) {
537 		be32_add_cpu(&sbp->sb_rextsize, tp->t_rextsize_delta);
538 		whole = 1;
539 	}
540 	if (tp->t_rbmblocks_delta) {
541 		be32_add_cpu(&sbp->sb_rbmblocks, tp->t_rbmblocks_delta);
542 		whole = 1;
543 	}
544 	if (tp->t_rblocks_delta) {
545 		be64_add_cpu(&sbp->sb_rblocks, tp->t_rblocks_delta);
546 		whole = 1;
547 	}
548 	if (tp->t_rextents_delta) {
549 		be64_add_cpu(&sbp->sb_rextents, tp->t_rextents_delta);
550 		whole = 1;
551 	}
552 	if (tp->t_rextslog_delta) {
553 		sbp->sb_rextslog += tp->t_rextslog_delta;
554 		whole = 1;
555 	}
556 
557 	xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
558 	if (whole)
559 		/*
560 		 * Log the whole thing, the fields are noncontiguous.
561 		 */
562 		xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb) - 1);
563 	else
564 		/*
565 		 * Since all the modifiable fields are contiguous, we
566 		 * can get away with this.
567 		 */
568 		xfs_trans_log_buf(tp, bp, offsetof(struct xfs_dsb, sb_icount),
569 				  offsetof(struct xfs_dsb, sb_frextents) +
570 				  sizeof(sbp->sb_frextents) - 1);
571 }
572 
573 /*
574  * xfs_trans_unreserve_and_mod_sb() is called to release unused reservations and
575  * apply superblock counter changes to the in-core superblock.  The
576  * t_res_fdblocks_delta and t_res_frextents_delta fields are explicitly NOT
577  * applied to the in-core superblock.  The idea is that that has already been
578  * done.
579  *
580  * If we are not logging superblock counters, then the inode allocated/free and
581  * used block counts are not updated in the on disk superblock. In this case,
582  * XFS_TRANS_SB_DIRTY will not be set when the transaction is updated but we
583  * still need to update the incore superblock with the changes.
584  *
585  * Deltas for the inode count are +/-64, hence we use a large batch size of 128
586  * so we don't need to take the counter lock on every update.
587  */
588 #define XFS_ICOUNT_BATCH	128
589 
590 void
591 xfs_trans_unreserve_and_mod_sb(
592 	struct xfs_trans	*tp)
593 {
594 	struct xfs_mount	*mp = tp->t_mountp;
595 	bool			rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0;
596 	int64_t			blkdelta = 0;
597 	int64_t			rtxdelta = 0;
598 	int64_t			idelta = 0;
599 	int64_t			ifreedelta = 0;
600 	int			error;
601 
602 	/* calculate deltas */
603 	if (tp->t_blk_res > 0)
604 		blkdelta = tp->t_blk_res;
605 	if ((tp->t_fdblocks_delta != 0) &&
606 	    (xfs_has_lazysbcount(mp) ||
607 	     (tp->t_flags & XFS_TRANS_SB_DIRTY)))
608 	        blkdelta += tp->t_fdblocks_delta;
609 
610 	if (tp->t_rtx_res > 0)
611 		rtxdelta = tp->t_rtx_res;
612 	if ((tp->t_frextents_delta != 0) &&
613 	    (tp->t_flags & XFS_TRANS_SB_DIRTY))
614 		rtxdelta += tp->t_frextents_delta;
615 
616 	if (xfs_has_lazysbcount(mp) ||
617 	     (tp->t_flags & XFS_TRANS_SB_DIRTY)) {
618 		idelta = tp->t_icount_delta;
619 		ifreedelta = tp->t_ifree_delta;
620 	}
621 
622 	/* apply the per-cpu counters */
623 	if (blkdelta) {
624 		error = xfs_mod_fdblocks(mp, blkdelta, rsvd);
625 		ASSERT(!error);
626 	}
627 
628 	if (idelta)
629 		percpu_counter_add_batch(&mp->m_icount, idelta,
630 					 XFS_ICOUNT_BATCH);
631 
632 	if (ifreedelta)
633 		percpu_counter_add(&mp->m_ifree, ifreedelta);
634 
635 	if (rtxdelta) {
636 		error = xfs_mod_frextents(mp, rtxdelta);
637 		ASSERT(!error);
638 	}
639 
640 	if (!(tp->t_flags & XFS_TRANS_SB_DIRTY))
641 		return;
642 
643 	/* apply remaining deltas */
644 	spin_lock(&mp->m_sb_lock);
645 	mp->m_sb.sb_fdblocks += tp->t_fdblocks_delta + tp->t_res_fdblocks_delta;
646 	mp->m_sb.sb_icount += idelta;
647 	mp->m_sb.sb_ifree += ifreedelta;
648 	/*
649 	 * Do not touch sb_frextents here because we are dealing with incore
650 	 * reservation.  sb_frextents is not part of the lazy sb counters so it
651 	 * must be consistent with the ondisk rtbitmap and must never include
652 	 * incore reservations.
653 	 */
654 	mp->m_sb.sb_dblocks += tp->t_dblocks_delta;
655 	mp->m_sb.sb_agcount += tp->t_agcount_delta;
656 	mp->m_sb.sb_imax_pct += tp->t_imaxpct_delta;
657 	mp->m_sb.sb_rextsize += tp->t_rextsize_delta;
658 	mp->m_sb.sb_rbmblocks += tp->t_rbmblocks_delta;
659 	mp->m_sb.sb_rblocks += tp->t_rblocks_delta;
660 	mp->m_sb.sb_rextents += tp->t_rextents_delta;
661 	mp->m_sb.sb_rextslog += tp->t_rextslog_delta;
662 	spin_unlock(&mp->m_sb_lock);
663 
664 	/*
665 	 * Debug checks outside of the spinlock so they don't lock up the
666 	 * machine if they fail.
667 	 */
668 	ASSERT(mp->m_sb.sb_imax_pct >= 0);
669 	ASSERT(mp->m_sb.sb_rextslog >= 0);
670 	return;
671 }
672 
673 /* Add the given log item to the transaction's list of log items. */
674 void
675 xfs_trans_add_item(
676 	struct xfs_trans	*tp,
677 	struct xfs_log_item	*lip)
678 {
679 	ASSERT(lip->li_log == tp->t_mountp->m_log);
680 	ASSERT(lip->li_ailp == tp->t_mountp->m_ail);
681 	ASSERT(list_empty(&lip->li_trans));
682 	ASSERT(!test_bit(XFS_LI_DIRTY, &lip->li_flags));
683 
684 	list_add_tail(&lip->li_trans, &tp->t_items);
685 	trace_xfs_trans_add_item(tp, _RET_IP_);
686 }
687 
688 /*
689  * Unlink the log item from the transaction. the log item is no longer
690  * considered dirty in this transaction, as the linked transaction has
691  * finished, either by abort or commit completion.
692  */
693 void
694 xfs_trans_del_item(
695 	struct xfs_log_item	*lip)
696 {
697 	clear_bit(XFS_LI_DIRTY, &lip->li_flags);
698 	list_del_init(&lip->li_trans);
699 }
700 
701 /* Detach and unlock all of the items in a transaction */
702 static void
703 xfs_trans_free_items(
704 	struct xfs_trans	*tp,
705 	bool			abort)
706 {
707 	struct xfs_log_item	*lip, *next;
708 
709 	trace_xfs_trans_free_items(tp, _RET_IP_);
710 
711 	list_for_each_entry_safe(lip, next, &tp->t_items, li_trans) {
712 		xfs_trans_del_item(lip);
713 		if (abort)
714 			set_bit(XFS_LI_ABORTED, &lip->li_flags);
715 		if (lip->li_ops->iop_release)
716 			lip->li_ops->iop_release(lip);
717 	}
718 }
719 
720 static inline void
721 xfs_log_item_batch_insert(
722 	struct xfs_ail		*ailp,
723 	struct xfs_ail_cursor	*cur,
724 	struct xfs_log_item	**log_items,
725 	int			nr_items,
726 	xfs_lsn_t		commit_lsn)
727 {
728 	int	i;
729 
730 	spin_lock(&ailp->ail_lock);
731 	/* xfs_trans_ail_update_bulk drops ailp->ail_lock */
732 	xfs_trans_ail_update_bulk(ailp, cur, log_items, nr_items, commit_lsn);
733 
734 	for (i = 0; i < nr_items; i++) {
735 		struct xfs_log_item *lip = log_items[i];
736 
737 		if (lip->li_ops->iop_unpin)
738 			lip->li_ops->iop_unpin(lip, 0);
739 	}
740 }
741 
742 /*
743  * Bulk operation version of xfs_trans_committed that takes a log vector of
744  * items to insert into the AIL. This uses bulk AIL insertion techniques to
745  * minimise lock traffic.
746  *
747  * If we are called with the aborted flag set, it is because a log write during
748  * a CIL checkpoint commit has failed. In this case, all the items in the
749  * checkpoint have already gone through iop_committed and iop_committing, which
750  * means that checkpoint commit abort handling is treated exactly the same
751  * as an iclog write error even though we haven't started any IO yet. Hence in
752  * this case all we need to do is iop_committed processing, followed by an
753  * iop_unpin(aborted) call.
754  *
755  * The AIL cursor is used to optimise the insert process. If commit_lsn is not
756  * at the end of the AIL, the insert cursor avoids the need to walk
757  * the AIL to find the insertion point on every xfs_log_item_batch_insert()
758  * call. This saves a lot of needless list walking and is a net win, even
759  * though it slightly increases that amount of AIL lock traffic to set it up
760  * and tear it down.
761  */
762 void
763 xfs_trans_committed_bulk(
764 	struct xfs_ail		*ailp,
765 	struct list_head	*lv_chain,
766 	xfs_lsn_t		commit_lsn,
767 	bool			aborted)
768 {
769 #define LOG_ITEM_BATCH_SIZE	32
770 	struct xfs_log_item	*log_items[LOG_ITEM_BATCH_SIZE];
771 	struct xfs_log_vec	*lv;
772 	struct xfs_ail_cursor	cur;
773 	int			i = 0;
774 
775 	spin_lock(&ailp->ail_lock);
776 	xfs_trans_ail_cursor_last(ailp, &cur, commit_lsn);
777 	spin_unlock(&ailp->ail_lock);
778 
779 	/* unpin all the log items */
780 	list_for_each_entry(lv, lv_chain, lv_list) {
781 		struct xfs_log_item	*lip = lv->lv_item;
782 		xfs_lsn_t		item_lsn;
783 
784 		if (aborted)
785 			set_bit(XFS_LI_ABORTED, &lip->li_flags);
786 
787 		if (lip->li_ops->flags & XFS_ITEM_RELEASE_WHEN_COMMITTED) {
788 			lip->li_ops->iop_release(lip);
789 			continue;
790 		}
791 
792 		if (lip->li_ops->iop_committed)
793 			item_lsn = lip->li_ops->iop_committed(lip, commit_lsn);
794 		else
795 			item_lsn = commit_lsn;
796 
797 		/* item_lsn of -1 means the item needs no further processing */
798 		if (XFS_LSN_CMP(item_lsn, (xfs_lsn_t)-1) == 0)
799 			continue;
800 
801 		/*
802 		 * if we are aborting the operation, no point in inserting the
803 		 * object into the AIL as we are in a shutdown situation.
804 		 */
805 		if (aborted) {
806 			ASSERT(xlog_is_shutdown(ailp->ail_log));
807 			if (lip->li_ops->iop_unpin)
808 				lip->li_ops->iop_unpin(lip, 1);
809 			continue;
810 		}
811 
812 		if (item_lsn != commit_lsn) {
813 
814 			/*
815 			 * Not a bulk update option due to unusual item_lsn.
816 			 * Push into AIL immediately, rechecking the lsn once
817 			 * we have the ail lock. Then unpin the item. This does
818 			 * not affect the AIL cursor the bulk insert path is
819 			 * using.
820 			 */
821 			spin_lock(&ailp->ail_lock);
822 			if (XFS_LSN_CMP(item_lsn, lip->li_lsn) > 0)
823 				xfs_trans_ail_update(ailp, lip, item_lsn);
824 			else
825 				spin_unlock(&ailp->ail_lock);
826 			if (lip->li_ops->iop_unpin)
827 				lip->li_ops->iop_unpin(lip, 0);
828 			continue;
829 		}
830 
831 		/* Item is a candidate for bulk AIL insert.  */
832 		log_items[i++] = lv->lv_item;
833 		if (i >= LOG_ITEM_BATCH_SIZE) {
834 			xfs_log_item_batch_insert(ailp, &cur, log_items,
835 					LOG_ITEM_BATCH_SIZE, commit_lsn);
836 			i = 0;
837 		}
838 	}
839 
840 	/* make sure we insert the remainder! */
841 	if (i)
842 		xfs_log_item_batch_insert(ailp, &cur, log_items, i, commit_lsn);
843 
844 	spin_lock(&ailp->ail_lock);
845 	xfs_trans_ail_cursor_done(&cur);
846 	spin_unlock(&ailp->ail_lock);
847 }
848 
849 /*
850  * Sort transaction items prior to running precommit operations. This will
851  * attempt to order the items such that they will always be locked in the same
852  * order. Items that have no sort function are moved to the end of the list
853  * and so are locked last.
854  *
855  * This may need refinement as different types of objects add sort functions.
856  *
857  * Function is more complex than it needs to be because we are comparing 64 bit
858  * values and the function only returns 32 bit values.
859  */
860 static int
861 xfs_trans_precommit_sort(
862 	void			*unused_arg,
863 	const struct list_head	*a,
864 	const struct list_head	*b)
865 {
866 	struct xfs_log_item	*lia = container_of(a,
867 					struct xfs_log_item, li_trans);
868 	struct xfs_log_item	*lib = container_of(b,
869 					struct xfs_log_item, li_trans);
870 	int64_t			diff;
871 
872 	/*
873 	 * If both items are non-sortable, leave them alone. If only one is
874 	 * sortable, move the non-sortable item towards the end of the list.
875 	 */
876 	if (!lia->li_ops->iop_sort && !lib->li_ops->iop_sort)
877 		return 0;
878 	if (!lia->li_ops->iop_sort)
879 		return 1;
880 	if (!lib->li_ops->iop_sort)
881 		return -1;
882 
883 	diff = lia->li_ops->iop_sort(lia) - lib->li_ops->iop_sort(lib);
884 	if (diff < 0)
885 		return -1;
886 	if (diff > 0)
887 		return 1;
888 	return 0;
889 }
890 
891 /*
892  * Run transaction precommit functions.
893  *
894  * If there is an error in any of the callouts, then stop immediately and
895  * trigger a shutdown to abort the transaction. There is no recovery possible
896  * from errors at this point as the transaction is dirty....
897  */
898 static int
899 xfs_trans_run_precommits(
900 	struct xfs_trans	*tp)
901 {
902 	struct xfs_mount	*mp = tp->t_mountp;
903 	struct xfs_log_item	*lip, *n;
904 	int			error = 0;
905 
906 	/*
907 	 * Sort the item list to avoid ABBA deadlocks with other transactions
908 	 * running precommit operations that lock multiple shared items such as
909 	 * inode cluster buffers.
910 	 */
911 	list_sort(NULL, &tp->t_items, xfs_trans_precommit_sort);
912 
913 	/*
914 	 * Precommit operations can remove the log item from the transaction
915 	 * if the log item exists purely to delay modifications until they
916 	 * can be ordered against other operations. Hence we have to use
917 	 * list_for_each_entry_safe() here.
918 	 */
919 	list_for_each_entry_safe(lip, n, &tp->t_items, li_trans) {
920 		if (!test_bit(XFS_LI_DIRTY, &lip->li_flags))
921 			continue;
922 		if (lip->li_ops->iop_precommit) {
923 			error = lip->li_ops->iop_precommit(tp, lip);
924 			if (error)
925 				break;
926 		}
927 	}
928 	if (error)
929 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
930 	return error;
931 }
932 
933 /*
934  * Commit the given transaction to the log.
935  *
936  * XFS disk error handling mechanism is not based on a typical
937  * transaction abort mechanism. Logically after the filesystem
938  * gets marked 'SHUTDOWN', we can't let any new transactions
939  * be durable - ie. committed to disk - because some metadata might
940  * be inconsistent. In such cases, this returns an error, and the
941  * caller may assume that all locked objects joined to the transaction
942  * have already been unlocked as if the commit had succeeded.
943  * Do not reference the transaction structure after this call.
944  */
945 static int
946 __xfs_trans_commit(
947 	struct xfs_trans	*tp,
948 	bool			regrant)
949 {
950 	struct xfs_mount	*mp = tp->t_mountp;
951 	struct xlog		*log = mp->m_log;
952 	xfs_csn_t		commit_seq = 0;
953 	int			error = 0;
954 	int			sync = tp->t_flags & XFS_TRANS_SYNC;
955 
956 	trace_xfs_trans_commit(tp, _RET_IP_);
957 
958 	error = xfs_trans_run_precommits(tp);
959 	if (error) {
960 		if (tp->t_flags & XFS_TRANS_PERM_LOG_RES)
961 			xfs_defer_cancel(tp);
962 		goto out_unreserve;
963 	}
964 
965 	/*
966 	 * Finish deferred items on final commit. Only permanent transactions
967 	 * should ever have deferred ops.
968 	 */
969 	WARN_ON_ONCE(!list_empty(&tp->t_dfops) &&
970 		     !(tp->t_flags & XFS_TRANS_PERM_LOG_RES));
971 	if (!regrant && (tp->t_flags & XFS_TRANS_PERM_LOG_RES)) {
972 		error = xfs_defer_finish_noroll(&tp);
973 		if (error)
974 			goto out_unreserve;
975 
976 		/* Run precommits from final tx in defer chain. */
977 		error = xfs_trans_run_precommits(tp);
978 		if (error)
979 			goto out_unreserve;
980 	}
981 
982 	/*
983 	 * If there is nothing to be logged by the transaction,
984 	 * then unlock all of the items associated with the
985 	 * transaction and free the transaction structure.
986 	 * Also make sure to return any reserved blocks to
987 	 * the free pool.
988 	 */
989 	if (!(tp->t_flags & XFS_TRANS_DIRTY))
990 		goto out_unreserve;
991 
992 	/*
993 	 * We must check against log shutdown here because we cannot abort log
994 	 * items and leave them dirty, inconsistent and unpinned in memory while
995 	 * the log is active. This leaves them open to being written back to
996 	 * disk, and that will lead to on-disk corruption.
997 	 */
998 	if (xlog_is_shutdown(log)) {
999 		error = -EIO;
1000 		goto out_unreserve;
1001 	}
1002 
1003 	ASSERT(tp->t_ticket != NULL);
1004 
1005 	/*
1006 	 * If we need to update the superblock, then do it now.
1007 	 */
1008 	if (tp->t_flags & XFS_TRANS_SB_DIRTY)
1009 		xfs_trans_apply_sb_deltas(tp);
1010 	xfs_trans_apply_dquot_deltas(tp);
1011 
1012 	xlog_cil_commit(log, tp, &commit_seq, regrant);
1013 
1014 	xfs_trans_free(tp);
1015 
1016 	/*
1017 	 * If the transaction needs to be synchronous, then force the
1018 	 * log out now and wait for it.
1019 	 */
1020 	if (sync) {
1021 		error = xfs_log_force_seq(mp, commit_seq, XFS_LOG_SYNC, NULL);
1022 		XFS_STATS_INC(mp, xs_trans_sync);
1023 	} else {
1024 		XFS_STATS_INC(mp, xs_trans_async);
1025 	}
1026 
1027 	return error;
1028 
1029 out_unreserve:
1030 	xfs_trans_unreserve_and_mod_sb(tp);
1031 
1032 	/*
1033 	 * It is indeed possible for the transaction to be not dirty but
1034 	 * the dqinfo portion to be.  All that means is that we have some
1035 	 * (non-persistent) quota reservations that need to be unreserved.
1036 	 */
1037 	xfs_trans_unreserve_and_mod_dquots(tp);
1038 	if (tp->t_ticket) {
1039 		if (regrant && !xlog_is_shutdown(log))
1040 			xfs_log_ticket_regrant(log, tp->t_ticket);
1041 		else
1042 			xfs_log_ticket_ungrant(log, tp->t_ticket);
1043 		tp->t_ticket = NULL;
1044 	}
1045 	xfs_trans_free_items(tp, !!error);
1046 	xfs_trans_free(tp);
1047 
1048 	XFS_STATS_INC(mp, xs_trans_empty);
1049 	return error;
1050 }
1051 
1052 int
1053 xfs_trans_commit(
1054 	struct xfs_trans	*tp)
1055 {
1056 	return __xfs_trans_commit(tp, false);
1057 }
1058 
1059 /*
1060  * Unlock all of the transaction's items and free the transaction.  If the
1061  * transaction is dirty, we must shut down the filesystem because there is no
1062  * way to restore them to their previous state.
1063  *
1064  * If the transaction has made a log reservation, make sure to release it as
1065  * well.
1066  *
1067  * This is a high level function (equivalent to xfs_trans_commit()) and so can
1068  * be called after the transaction has effectively been aborted due to the mount
1069  * being shut down. However, if the mount has not been shut down and the
1070  * transaction is dirty we will shut the mount down and, in doing so, that
1071  * guarantees that the log is shut down, too. Hence we don't need to be as
1072  * careful with shutdown state and dirty items here as we need to be in
1073  * xfs_trans_commit().
1074  */
1075 void
1076 xfs_trans_cancel(
1077 	struct xfs_trans	*tp)
1078 {
1079 	struct xfs_mount	*mp = tp->t_mountp;
1080 	struct xlog		*log = mp->m_log;
1081 	bool			dirty = (tp->t_flags & XFS_TRANS_DIRTY);
1082 
1083 	trace_xfs_trans_cancel(tp, _RET_IP_);
1084 
1085 	/*
1086 	 * It's never valid to cancel a transaction with deferred ops attached,
1087 	 * because the transaction is effectively dirty.  Complain about this
1088 	 * loudly before freeing the in-memory defer items and shutting down the
1089 	 * filesystem.
1090 	 */
1091 	if (!list_empty(&tp->t_dfops)) {
1092 		ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
1093 		dirty = true;
1094 		xfs_defer_cancel(tp);
1095 	}
1096 
1097 	/*
1098 	 * See if the caller is relying on us to shut down the filesystem. We
1099 	 * only want an error report if there isn't already a shutdown in
1100 	 * progress, so we only need to check against the mount shutdown state
1101 	 * here.
1102 	 */
1103 	if (dirty && !xfs_is_shutdown(mp)) {
1104 		XFS_ERROR_REPORT("xfs_trans_cancel", XFS_ERRLEVEL_LOW, mp);
1105 		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
1106 	}
1107 #ifdef DEBUG
1108 	/* Log items need to be consistent until the log is shut down. */
1109 	if (!dirty && !xlog_is_shutdown(log)) {
1110 		struct xfs_log_item *lip;
1111 
1112 		list_for_each_entry(lip, &tp->t_items, li_trans)
1113 			ASSERT(!xlog_item_is_intent_done(lip));
1114 	}
1115 #endif
1116 	xfs_trans_unreserve_and_mod_sb(tp);
1117 	xfs_trans_unreserve_and_mod_dquots(tp);
1118 
1119 	if (tp->t_ticket) {
1120 		xfs_log_ticket_ungrant(log, tp->t_ticket);
1121 		tp->t_ticket = NULL;
1122 	}
1123 
1124 	xfs_trans_free_items(tp, dirty);
1125 	xfs_trans_free(tp);
1126 }
1127 
1128 /*
1129  * Roll from one trans in the sequence of PERMANENT transactions to
1130  * the next: permanent transactions are only flushed out when
1131  * committed with xfs_trans_commit(), but we still want as soon
1132  * as possible to let chunks of it go to the log. So we commit the
1133  * chunk we've been working on and get a new transaction to continue.
1134  */
1135 int
1136 xfs_trans_roll(
1137 	struct xfs_trans	**tpp)
1138 {
1139 	struct xfs_trans	*trans = *tpp;
1140 	struct xfs_trans_res	tres;
1141 	int			error;
1142 
1143 	trace_xfs_trans_roll(trans, _RET_IP_);
1144 
1145 	/*
1146 	 * Copy the critical parameters from one trans to the next.
1147 	 */
1148 	tres.tr_logres = trans->t_log_res;
1149 	tres.tr_logcount = trans->t_log_count;
1150 
1151 	*tpp = xfs_trans_dup(trans);
1152 
1153 	/*
1154 	 * Commit the current transaction.
1155 	 * If this commit failed, then it'd just unlock those items that
1156 	 * are not marked ihold. That also means that a filesystem shutdown
1157 	 * is in progress. The caller takes the responsibility to cancel
1158 	 * the duplicate transaction that gets returned.
1159 	 */
1160 	error = __xfs_trans_commit(trans, true);
1161 	if (error)
1162 		return error;
1163 
1164 	/*
1165 	 * Reserve space in the log for the next transaction.
1166 	 * This also pushes items in the "AIL", the list of logged items,
1167 	 * out to disk if they are taking up space at the tail of the log
1168 	 * that we want to use.  This requires that either nothing be locked
1169 	 * across this call, or that anything that is locked be logged in
1170 	 * the prior and the next transactions.
1171 	 */
1172 	tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
1173 	return xfs_trans_reserve(*tpp, &tres, 0, 0);
1174 }
1175 
1176 /*
1177  * Allocate an transaction, lock and join the inode to it, and reserve quota.
1178  *
1179  * The caller must ensure that the on-disk dquots attached to this inode have
1180  * already been allocated and initialized.  The caller is responsible for
1181  * releasing ILOCK_EXCL if a new transaction is returned.
1182  */
1183 int
1184 xfs_trans_alloc_inode(
1185 	struct xfs_inode	*ip,
1186 	struct xfs_trans_res	*resv,
1187 	unsigned int		dblocks,
1188 	unsigned int		rblocks,
1189 	bool			force,
1190 	struct xfs_trans	**tpp)
1191 {
1192 	struct xfs_trans	*tp;
1193 	struct xfs_mount	*mp = ip->i_mount;
1194 	bool			retried = false;
1195 	int			error;
1196 
1197 retry:
1198 	error = xfs_trans_alloc(mp, resv, dblocks,
1199 			rblocks / mp->m_sb.sb_rextsize,
1200 			force ? XFS_TRANS_RESERVE : 0, &tp);
1201 	if (error)
1202 		return error;
1203 
1204 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1205 	xfs_trans_ijoin(tp, ip, 0);
1206 
1207 	error = xfs_qm_dqattach_locked(ip, false);
1208 	if (error) {
1209 		/* Caller should have allocated the dquots! */
1210 		ASSERT(error != -ENOENT);
1211 		goto out_cancel;
1212 	}
1213 
1214 	error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks, force);
1215 	if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
1216 		xfs_trans_cancel(tp);
1217 		xfs_iunlock(ip, XFS_ILOCK_EXCL);
1218 		xfs_blockgc_free_quota(ip, 0);
1219 		retried = true;
1220 		goto retry;
1221 	}
1222 	if (error)
1223 		goto out_cancel;
1224 
1225 	*tpp = tp;
1226 	return 0;
1227 
1228 out_cancel:
1229 	xfs_trans_cancel(tp);
1230 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
1231 	return error;
1232 }
1233 
1234 /*
1235  * Allocate an transaction in preparation for inode creation by reserving quota
1236  * against the given dquots.  Callers are not required to hold any inode locks.
1237  */
1238 int
1239 xfs_trans_alloc_icreate(
1240 	struct xfs_mount	*mp,
1241 	struct xfs_trans_res	*resv,
1242 	struct xfs_dquot	*udqp,
1243 	struct xfs_dquot	*gdqp,
1244 	struct xfs_dquot	*pdqp,
1245 	unsigned int		dblocks,
1246 	struct xfs_trans	**tpp)
1247 {
1248 	struct xfs_trans	*tp;
1249 	bool			retried = false;
1250 	int			error;
1251 
1252 retry:
1253 	error = xfs_trans_alloc(mp, resv, dblocks, 0, 0, &tp);
1254 	if (error)
1255 		return error;
1256 
1257 	error = xfs_trans_reserve_quota_icreate(tp, udqp, gdqp, pdqp, dblocks);
1258 	if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
1259 		xfs_trans_cancel(tp);
1260 		xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
1261 		retried = true;
1262 		goto retry;
1263 	}
1264 	if (error) {
1265 		xfs_trans_cancel(tp);
1266 		return error;
1267 	}
1268 
1269 	*tpp = tp;
1270 	return 0;
1271 }
1272 
1273 /*
1274  * Allocate an transaction, lock and join the inode to it, and reserve quota
1275  * in preparation for inode attribute changes that include uid, gid, or prid
1276  * changes.
1277  *
1278  * The caller must ensure that the on-disk dquots attached to this inode have
1279  * already been allocated and initialized.  The ILOCK will be dropped when the
1280  * transaction is committed or cancelled.
1281  */
1282 int
1283 xfs_trans_alloc_ichange(
1284 	struct xfs_inode	*ip,
1285 	struct xfs_dquot	*new_udqp,
1286 	struct xfs_dquot	*new_gdqp,
1287 	struct xfs_dquot	*new_pdqp,
1288 	bool			force,
1289 	struct xfs_trans	**tpp)
1290 {
1291 	struct xfs_trans	*tp;
1292 	struct xfs_mount	*mp = ip->i_mount;
1293 	struct xfs_dquot	*udqp;
1294 	struct xfs_dquot	*gdqp;
1295 	struct xfs_dquot	*pdqp;
1296 	bool			retried = false;
1297 	int			error;
1298 
1299 retry:
1300 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
1301 	if (error)
1302 		return error;
1303 
1304 	xfs_ilock(ip, XFS_ILOCK_EXCL);
1305 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1306 
1307 	error = xfs_qm_dqattach_locked(ip, false);
1308 	if (error) {
1309 		/* Caller should have allocated the dquots! */
1310 		ASSERT(error != -ENOENT);
1311 		goto out_cancel;
1312 	}
1313 
1314 	/*
1315 	 * For each quota type, skip quota reservations if the inode's dquots
1316 	 * now match the ones that came from the caller, or the caller didn't
1317 	 * pass one in.  The inode's dquots can change if we drop the ILOCK to
1318 	 * perform a blockgc scan, so we must preserve the caller's arguments.
1319 	 */
1320 	udqp = (new_udqp != ip->i_udquot) ? new_udqp : NULL;
1321 	gdqp = (new_gdqp != ip->i_gdquot) ? new_gdqp : NULL;
1322 	pdqp = (new_pdqp != ip->i_pdquot) ? new_pdqp : NULL;
1323 	if (udqp || gdqp || pdqp) {
1324 		unsigned int	qflags = XFS_QMOPT_RES_REGBLKS;
1325 
1326 		if (force)
1327 			qflags |= XFS_QMOPT_FORCE_RES;
1328 
1329 		/*
1330 		 * Reserve enough quota to handle blocks on disk and reserved
1331 		 * for a delayed allocation.  We'll actually transfer the
1332 		 * delalloc reservation between dquots at chown time, even
1333 		 * though that part is only semi-transactional.
1334 		 */
1335 		error = xfs_trans_reserve_quota_bydquots(tp, mp, udqp, gdqp,
1336 				pdqp, ip->i_nblocks + ip->i_delayed_blks,
1337 				1, qflags);
1338 		if ((error == -EDQUOT || error == -ENOSPC) && !retried) {
1339 			xfs_trans_cancel(tp);
1340 			xfs_blockgc_free_dquots(mp, udqp, gdqp, pdqp, 0);
1341 			retried = true;
1342 			goto retry;
1343 		}
1344 		if (error)
1345 			goto out_cancel;
1346 	}
1347 
1348 	*tpp = tp;
1349 	return 0;
1350 
1351 out_cancel:
1352 	xfs_trans_cancel(tp);
1353 	return error;
1354 }
1355 
1356 /*
1357  * Allocate an transaction, lock and join the directory and child inodes to it,
1358  * and reserve quota for a directory update.  If there isn't sufficient space,
1359  * @dblocks will be set to zero for a reservationless directory update and
1360  * @nospace_error will be set to a negative errno describing the space
1361  * constraint we hit.
1362  *
1363  * The caller must ensure that the on-disk dquots attached to this inode have
1364  * already been allocated and initialized.  The ILOCKs will be dropped when the
1365  * transaction is committed or cancelled.
1366  */
1367 int
1368 xfs_trans_alloc_dir(
1369 	struct xfs_inode	*dp,
1370 	struct xfs_trans_res	*resv,
1371 	struct xfs_inode	*ip,
1372 	unsigned int		*dblocks,
1373 	struct xfs_trans	**tpp,
1374 	int			*nospace_error)
1375 {
1376 	struct xfs_trans	*tp;
1377 	struct xfs_mount	*mp = ip->i_mount;
1378 	unsigned int		resblks;
1379 	bool			retried = false;
1380 	int			error;
1381 
1382 retry:
1383 	*nospace_error = 0;
1384 	resblks = *dblocks;
1385 	error = xfs_trans_alloc(mp, resv, resblks, 0, 0, &tp);
1386 	if (error == -ENOSPC) {
1387 		*nospace_error = error;
1388 		resblks = 0;
1389 		error = xfs_trans_alloc(mp, resv, resblks, 0, 0, &tp);
1390 	}
1391 	if (error)
1392 		return error;
1393 
1394 	xfs_lock_two_inodes(dp, XFS_ILOCK_EXCL, ip, XFS_ILOCK_EXCL);
1395 
1396 	xfs_trans_ijoin(tp, dp, XFS_ILOCK_EXCL);
1397 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1398 
1399 	error = xfs_qm_dqattach_locked(dp, false);
1400 	if (error) {
1401 		/* Caller should have allocated the dquots! */
1402 		ASSERT(error != -ENOENT);
1403 		goto out_cancel;
1404 	}
1405 
1406 	error = xfs_qm_dqattach_locked(ip, false);
1407 	if (error) {
1408 		/* Caller should have allocated the dquots! */
1409 		ASSERT(error != -ENOENT);
1410 		goto out_cancel;
1411 	}
1412 
1413 	if (resblks == 0)
1414 		goto done;
1415 
1416 	error = xfs_trans_reserve_quota_nblks(tp, dp, resblks, 0, false);
1417 	if (error == -EDQUOT || error == -ENOSPC) {
1418 		if (!retried) {
1419 			xfs_trans_cancel(tp);
1420 			xfs_blockgc_free_quota(dp, 0);
1421 			retried = true;
1422 			goto retry;
1423 		}
1424 
1425 		*nospace_error = error;
1426 		resblks = 0;
1427 		error = 0;
1428 	}
1429 	if (error)
1430 		goto out_cancel;
1431 
1432 done:
1433 	*tpp = tp;
1434 	*dblocks = resblks;
1435 	return 0;
1436 
1437 out_cancel:
1438 	xfs_trans_cancel(tp);
1439 	return error;
1440 }
1441