xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision 1da177e4)
1 /*
2  * Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 
33 /*
34  * This file contains the implementation of the xfs_efi_log_item
35  * and xfs_efd_log_item items.
36  */
37 
38 #include "xfs.h"
39 
40 #include "xfs_macros.h"
41 #include "xfs_types.h"
42 #include "xfs_inum.h"
43 #include "xfs_log.h"
44 #include "xfs_trans.h"
45 #include "xfs_buf_item.h"
46 #include "xfs_sb.h"
47 #include "xfs_dir.h"
48 #include "xfs_dmapi.h"
49 #include "xfs_mount.h"
50 #include "xfs_trans_priv.h"
51 #include "xfs_extfree_item.h"
52 
53 
54 kmem_zone_t	*xfs_efi_zone;
55 kmem_zone_t	*xfs_efd_zone;
56 
57 STATIC void	xfs_efi_item_unlock(xfs_efi_log_item_t *);
58 STATIC void	xfs_efi_item_abort(xfs_efi_log_item_t *);
59 STATIC void	xfs_efd_item_abort(xfs_efd_log_item_t *);
60 
61 
62 
63 /*
64  * This returns the number of iovecs needed to log the given efi item.
65  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
66  * structure.
67  */
68 /*ARGSUSED*/
69 STATIC uint
70 xfs_efi_item_size(xfs_efi_log_item_t *efip)
71 {
72 	return 1;
73 }
74 
75 /*
76  * This is called to fill in the vector of log iovecs for the
77  * given efi log item. We use only 1 iovec, and we point that
78  * at the efi_log_format structure embedded in the efi item.
79  * It is at this point that we assert that all of the extent
80  * slots in the efi item have been filled.
81  */
82 STATIC void
83 xfs_efi_item_format(xfs_efi_log_item_t	*efip,
84 		    xfs_log_iovec_t	*log_vector)
85 {
86 	uint	size;
87 
88 	ASSERT(efip->efi_next_extent == efip->efi_format.efi_nextents);
89 
90 	efip->efi_format.efi_type = XFS_LI_EFI;
91 
92 	size = sizeof(xfs_efi_log_format_t);
93 	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
94 	efip->efi_format.efi_size = 1;
95 
96 	log_vector->i_addr = (xfs_caddr_t)&(efip->efi_format);
97 	log_vector->i_len = size;
98 	ASSERT(size >= sizeof(xfs_efi_log_format_t));
99 }
100 
101 
102 /*
103  * Pinning has no meaning for an efi item, so just return.
104  */
105 /*ARGSUSED*/
106 STATIC void
107 xfs_efi_item_pin(xfs_efi_log_item_t *efip)
108 {
109 	return;
110 }
111 
112 
113 /*
114  * While EFIs cannot really be pinned, the unpin operation is the
115  * last place at which the EFI is manipulated during a transaction.
116  * Here we coordinate with xfs_efi_cancel() to determine who gets to
117  * free the EFI.
118  */
119 /*ARGSUSED*/
120 STATIC void
121 xfs_efi_item_unpin(xfs_efi_log_item_t *efip, int stale)
122 {
123 	int		nexts;
124 	int		size;
125 	xfs_mount_t	*mp;
126 	SPLDECL(s);
127 
128 	mp = efip->efi_item.li_mountp;
129 	AIL_LOCK(mp, s);
130 	if (efip->efi_flags & XFS_EFI_CANCELED) {
131 		/*
132 		 * xfs_trans_delete_ail() drops the AIL lock.
133 		 */
134 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
135 
136 		nexts = efip->efi_format.efi_nextents;
137 		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
138 			size = sizeof(xfs_efi_log_item_t);
139 			size += (nexts - 1) * sizeof(xfs_extent_t);
140 			kmem_free(efip, size);
141 		} else {
142 			kmem_zone_free(xfs_efi_zone, efip);
143 		}
144 	} else {
145 		efip->efi_flags |= XFS_EFI_COMMITTED;
146 		AIL_UNLOCK(mp, s);
147 	}
148 
149 	return;
150 }
151 
152 /*
153  * like unpin only we have to also clear the xaction descriptor
154  * pointing the log item if we free the item.  This routine duplicates
155  * unpin because efi_flags is protected by the AIL lock.  Freeing
156  * the descriptor and then calling unpin would force us to drop the AIL
157  * lock which would open up a race condition.
158  */
159 STATIC void
160 xfs_efi_item_unpin_remove(xfs_efi_log_item_t *efip, xfs_trans_t *tp)
161 {
162 	int		nexts;
163 	int		size;
164 	xfs_mount_t	*mp;
165 	xfs_log_item_desc_t	*lidp;
166 	SPLDECL(s);
167 
168 	mp = efip->efi_item.li_mountp;
169 	AIL_LOCK(mp, s);
170 	if (efip->efi_flags & XFS_EFI_CANCELED) {
171 		/*
172 		 * free the xaction descriptor pointing to this item
173 		 */
174 		lidp = xfs_trans_find_item(tp, (xfs_log_item_t *) efip);
175 		xfs_trans_free_item(tp, lidp);
176 		/*
177 		 * pull the item off the AIL.
178 		 * xfs_trans_delete_ail() drops the AIL lock.
179 		 */
180 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
181 		/*
182 		 * now free the item itself
183 		 */
184 		nexts = efip->efi_format.efi_nextents;
185 		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
186 			size = sizeof(xfs_efi_log_item_t);
187 			size += (nexts - 1) * sizeof(xfs_extent_t);
188 			kmem_free(efip, size);
189 		} else {
190 			kmem_zone_free(xfs_efi_zone, efip);
191 		}
192 	} else {
193 		efip->efi_flags |= XFS_EFI_COMMITTED;
194 		AIL_UNLOCK(mp, s);
195 	}
196 
197 	return;
198 }
199 
200 /*
201  * Efi items have no locking or pushing.  However, since EFIs are
202  * pulled from the AIL when their corresponding EFDs are committed
203  * to disk, their situation is very similar to being pinned.  Return
204  * XFS_ITEM_PINNED so that the caller will eventually flush the log.
205  * This should help in getting the EFI out of the AIL.
206  */
207 /*ARGSUSED*/
208 STATIC uint
209 xfs_efi_item_trylock(xfs_efi_log_item_t *efip)
210 {
211 	return XFS_ITEM_PINNED;
212 }
213 
214 /*
215  * Efi items have no locking, so just return.
216  */
217 /*ARGSUSED*/
218 STATIC void
219 xfs_efi_item_unlock(xfs_efi_log_item_t *efip)
220 {
221 	if (efip->efi_item.li_flags & XFS_LI_ABORTED)
222 		xfs_efi_item_abort(efip);
223 	return;
224 }
225 
226 /*
227  * The EFI is logged only once and cannot be moved in the log, so
228  * simply return the lsn at which it's been logged.  The canceled
229  * flag is not paid any attention here.  Checking for that is delayed
230  * until the EFI is unpinned.
231  */
232 /*ARGSUSED*/
233 STATIC xfs_lsn_t
234 xfs_efi_item_committed(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
235 {
236 	return lsn;
237 }
238 
239 /*
240  * This is called when the transaction logging the EFI is aborted.
241  * Free up the EFI and return.  No need to clean up the slot for
242  * the item in the transaction.  That was done by the unpin code
243  * which is called prior to this routine in the abort/fs-shutdown path.
244  */
245 STATIC void
246 xfs_efi_item_abort(xfs_efi_log_item_t *efip)
247 {
248 	int	nexts;
249 	int	size;
250 
251 	nexts = efip->efi_format.efi_nextents;
252 	if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
253 		size = sizeof(xfs_efi_log_item_t);
254 		size += (nexts - 1) * sizeof(xfs_extent_t);
255 		kmem_free(efip, size);
256 	} else {
257 		kmem_zone_free(xfs_efi_zone, efip);
258 	}
259 	return;
260 }
261 
262 /*
263  * There isn't much you can do to push on an efi item.  It is simply
264  * stuck waiting for all of its corresponding efd items to be
265  * committed to disk.
266  */
267 /*ARGSUSED*/
268 STATIC void
269 xfs_efi_item_push(xfs_efi_log_item_t *efip)
270 {
271 	return;
272 }
273 
274 /*
275  * The EFI dependency tracking op doesn't do squat.  It can't because
276  * it doesn't know where the free extent is coming from.  The dependency
277  * tracking has to be handled by the "enclosing" metadata object.  For
278  * example, for inodes, the inode is locked throughout the extent freeing
279  * so the dependency should be recorded there.
280  */
281 /*ARGSUSED*/
282 STATIC void
283 xfs_efi_item_committing(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
284 {
285 	return;
286 }
287 
288 /*
289  * This is the ops vector shared by all efi log items.
290  */
291 struct xfs_item_ops xfs_efi_item_ops = {
292 	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efi_item_size,
293 	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
294 					xfs_efi_item_format,
295 	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efi_item_pin,
296 	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efi_item_unpin,
297 	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t *))
298 					xfs_efi_item_unpin_remove,
299 	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efi_item_trylock,
300 	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efi_item_unlock,
301 	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
302 					xfs_efi_item_committed,
303 	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efi_item_push,
304 	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efi_item_abort,
305 	.iop_pushbuf	= NULL,
306 	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
307 					xfs_efi_item_committing
308 };
309 
310 
311 /*
312  * Allocate and initialize an efi item with the given number of extents.
313  */
314 xfs_efi_log_item_t *
315 xfs_efi_init(xfs_mount_t	*mp,
316 	     uint		nextents)
317 
318 {
319 	xfs_efi_log_item_t	*efip;
320 	uint			size;
321 
322 	ASSERT(nextents > 0);
323 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
324 		size = (uint)(sizeof(xfs_efi_log_item_t) +
325 			((nextents - 1) * sizeof(xfs_extent_t)));
326 		efip = (xfs_efi_log_item_t*)kmem_zalloc(size, KM_SLEEP);
327 	} else {
328 		efip = (xfs_efi_log_item_t*)kmem_zone_zalloc(xfs_efi_zone,
329 							     KM_SLEEP);
330 	}
331 
332 	efip->efi_item.li_type = XFS_LI_EFI;
333 	efip->efi_item.li_ops = &xfs_efi_item_ops;
334 	efip->efi_item.li_mountp = mp;
335 	efip->efi_format.efi_nextents = nextents;
336 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
337 
338 	return (efip);
339 }
340 
341 /*
342  * This is called by the efd item code below to release references to
343  * the given efi item.  Each efd calls this with the number of
344  * extents that it has logged, and when the sum of these reaches
345  * the total number of extents logged by this efi item we can free
346  * the efi item.
347  *
348  * Freeing the efi item requires that we remove it from the AIL.
349  * We'll use the AIL lock to protect our counters as well as
350  * the removal from the AIL.
351  */
352 void
353 xfs_efi_release(xfs_efi_log_item_t	*efip,
354 		uint			nextents)
355 {
356 	xfs_mount_t	*mp;
357 	int		extents_left;
358 	uint		size;
359 	int		nexts;
360 	SPLDECL(s);
361 
362 	mp = efip->efi_item.li_mountp;
363 	ASSERT(efip->efi_next_extent > 0);
364 	ASSERT(efip->efi_flags & XFS_EFI_COMMITTED);
365 
366 	AIL_LOCK(mp, s);
367 	ASSERT(efip->efi_next_extent >= nextents);
368 	efip->efi_next_extent -= nextents;
369 	extents_left = efip->efi_next_extent;
370 	if (extents_left == 0) {
371 		/*
372 		 * xfs_trans_delete_ail() drops the AIL lock.
373 		 */
374 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
375 	} else {
376 		AIL_UNLOCK(mp, s);
377 	}
378 
379 	if (extents_left == 0) {
380 		nexts = efip->efi_format.efi_nextents;
381 		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
382 			size = sizeof(xfs_efi_log_item_t);
383 			size += (nexts - 1) * sizeof(xfs_extent_t);
384 			kmem_free(efip, size);
385 		} else {
386 			kmem_zone_free(xfs_efi_zone, efip);
387 		}
388 	}
389 }
390 
391 /*
392  * This is called when the transaction that should be committing the
393  * EFD corresponding to the given EFI is aborted.  The committed and
394  * canceled flags are used to coordinate the freeing of the EFI and
395  * the references by the transaction that committed it.
396  */
397 STATIC void
398 xfs_efi_cancel(
399 	xfs_efi_log_item_t	*efip)
400 {
401 	int		nexts;
402 	int		size;
403 	xfs_mount_t	*mp;
404 	SPLDECL(s);
405 
406 	mp = efip->efi_item.li_mountp;
407 	AIL_LOCK(mp, s);
408 	if (efip->efi_flags & XFS_EFI_COMMITTED) {
409 		/*
410 		 * xfs_trans_delete_ail() drops the AIL lock.
411 		 */
412 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
413 
414 		nexts = efip->efi_format.efi_nextents;
415 		if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
416 			size = sizeof(xfs_efi_log_item_t);
417 			size += (nexts - 1) * sizeof(xfs_extent_t);
418 			kmem_free(efip, size);
419 		} else {
420 			kmem_zone_free(xfs_efi_zone, efip);
421 		}
422 	} else {
423 		efip->efi_flags |= XFS_EFI_CANCELED;
424 		AIL_UNLOCK(mp, s);
425 	}
426 
427 	return;
428 }
429 
430 
431 
432 
433 
434 /*
435  * This returns the number of iovecs needed to log the given efd item.
436  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
437  * structure.
438  */
439 /*ARGSUSED*/
440 STATIC uint
441 xfs_efd_item_size(xfs_efd_log_item_t *efdp)
442 {
443 	return 1;
444 }
445 
446 /*
447  * This is called to fill in the vector of log iovecs for the
448  * given efd log item. We use only 1 iovec, and we point that
449  * at the efd_log_format structure embedded in the efd item.
450  * It is at this point that we assert that all of the extent
451  * slots in the efd item have been filled.
452  */
453 STATIC void
454 xfs_efd_item_format(xfs_efd_log_item_t	*efdp,
455 		    xfs_log_iovec_t	*log_vector)
456 {
457 	uint	size;
458 
459 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
460 
461 	efdp->efd_format.efd_type = XFS_LI_EFD;
462 
463 	size = sizeof(xfs_efd_log_format_t);
464 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
465 	efdp->efd_format.efd_size = 1;
466 
467 	log_vector->i_addr = (xfs_caddr_t)&(efdp->efd_format);
468 	log_vector->i_len = size;
469 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
470 }
471 
472 
473 /*
474  * Pinning has no meaning for an efd item, so just return.
475  */
476 /*ARGSUSED*/
477 STATIC void
478 xfs_efd_item_pin(xfs_efd_log_item_t *efdp)
479 {
480 	return;
481 }
482 
483 
484 /*
485  * Since pinning has no meaning for an efd item, unpinning does
486  * not either.
487  */
488 /*ARGSUSED*/
489 STATIC void
490 xfs_efd_item_unpin(xfs_efd_log_item_t *efdp, int stale)
491 {
492 	return;
493 }
494 
495 /*ARGSUSED*/
496 STATIC void
497 xfs_efd_item_unpin_remove(xfs_efd_log_item_t *efdp, xfs_trans_t *tp)
498 {
499 	return;
500 }
501 
502 /*
503  * Efd items have no locking, so just return success.
504  */
505 /*ARGSUSED*/
506 STATIC uint
507 xfs_efd_item_trylock(xfs_efd_log_item_t *efdp)
508 {
509 	return XFS_ITEM_LOCKED;
510 }
511 
512 /*
513  * Efd items have no locking or pushing, so return failure
514  * so that the caller doesn't bother with us.
515  */
516 /*ARGSUSED*/
517 STATIC void
518 xfs_efd_item_unlock(xfs_efd_log_item_t *efdp)
519 {
520 	if (efdp->efd_item.li_flags & XFS_LI_ABORTED)
521 		xfs_efd_item_abort(efdp);
522 	return;
523 }
524 
525 /*
526  * When the efd item is committed to disk, all we need to do
527  * is delete our reference to our partner efi item and then
528  * free ourselves.  Since we're freeing ourselves we must
529  * return -1 to keep the transaction code from further referencing
530  * this item.
531  */
532 /*ARGSUSED*/
533 STATIC xfs_lsn_t
534 xfs_efd_item_committed(xfs_efd_log_item_t *efdp, xfs_lsn_t lsn)
535 {
536 	uint	size;
537 	int	nexts;
538 
539 	/*
540 	 * If we got a log I/O error, it's always the case that the LR with the
541 	 * EFI got unpinned and freed before the EFD got aborted.
542 	 */
543 	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
544 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
545 
546 	nexts = efdp->efd_format.efd_nextents;
547 	if (nexts > XFS_EFD_MAX_FAST_EXTENTS) {
548 		size = sizeof(xfs_efd_log_item_t);
549 		size += (nexts - 1) * sizeof(xfs_extent_t);
550 		kmem_free(efdp, size);
551 	} else {
552 		kmem_zone_free(xfs_efd_zone, efdp);
553 	}
554 
555 	return (xfs_lsn_t)-1;
556 }
557 
558 /*
559  * The transaction of which this EFD is a part has been aborted.
560  * Inform its companion EFI of this fact and then clean up after
561  * ourselves.  No need to clean up the slot for the item in the
562  * transaction.  That was done by the unpin code which is called
563  * prior to this routine in the abort/fs-shutdown path.
564  */
565 STATIC void
566 xfs_efd_item_abort(xfs_efd_log_item_t *efdp)
567 {
568 	int	nexts;
569 	int	size;
570 
571 	/*
572 	 * If we got a log I/O error, it's always the case that the LR with the
573 	 * EFI got unpinned and freed before the EFD got aborted. So don't
574 	 * reference the EFI at all in that case.
575 	 */
576 	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
577 		xfs_efi_cancel(efdp->efd_efip);
578 
579 	nexts = efdp->efd_format.efd_nextents;
580 	if (nexts > XFS_EFD_MAX_FAST_EXTENTS) {
581 		size = sizeof(xfs_efd_log_item_t);
582 		size += (nexts - 1) * sizeof(xfs_extent_t);
583 		kmem_free(efdp, size);
584 	} else {
585 		kmem_zone_free(xfs_efd_zone, efdp);
586 	}
587 	return;
588 }
589 
590 /*
591  * There isn't much you can do to push on an efd item.  It is simply
592  * stuck waiting for the log to be flushed to disk.
593  */
594 /*ARGSUSED*/
595 STATIC void
596 xfs_efd_item_push(xfs_efd_log_item_t *efdp)
597 {
598 	return;
599 }
600 
601 /*
602  * The EFD dependency tracking op doesn't do squat.  It can't because
603  * it doesn't know where the free extent is coming from.  The dependency
604  * tracking has to be handled by the "enclosing" metadata object.  For
605  * example, for inodes, the inode is locked throughout the extent freeing
606  * so the dependency should be recorded there.
607  */
608 /*ARGSUSED*/
609 STATIC void
610 xfs_efd_item_committing(xfs_efd_log_item_t *efip, xfs_lsn_t lsn)
611 {
612 	return;
613 }
614 
615 /*
616  * This is the ops vector shared by all efd log items.
617  */
618 struct xfs_item_ops xfs_efd_item_ops = {
619 	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efd_item_size,
620 	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
621 					xfs_efd_item_format,
622 	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efd_item_pin,
623 	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efd_item_unpin,
624 	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t*))
625 					xfs_efd_item_unpin_remove,
626 	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efd_item_trylock,
627 	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efd_item_unlock,
628 	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
629 					xfs_efd_item_committed,
630 	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efd_item_push,
631 	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efd_item_abort,
632 	.iop_pushbuf	= NULL,
633 	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
634 					xfs_efd_item_committing
635 };
636 
637 
638 /*
639  * Allocate and initialize an efd item with the given number of extents.
640  */
641 xfs_efd_log_item_t *
642 xfs_efd_init(xfs_mount_t	*mp,
643 	     xfs_efi_log_item_t	*efip,
644 	     uint		nextents)
645 
646 {
647 	xfs_efd_log_item_t	*efdp;
648 	uint			size;
649 
650 	ASSERT(nextents > 0);
651 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
652 		size = (uint)(sizeof(xfs_efd_log_item_t) +
653 			((nextents - 1) * sizeof(xfs_extent_t)));
654 		efdp = (xfs_efd_log_item_t*)kmem_zalloc(size, KM_SLEEP);
655 	} else {
656 		efdp = (xfs_efd_log_item_t*)kmem_zone_zalloc(xfs_efd_zone,
657 							     KM_SLEEP);
658 	}
659 
660 	efdp->efd_item.li_type = XFS_LI_EFD;
661 	efdp->efd_item.li_ops = &xfs_efd_item_ops;
662 	efdp->efd_item.li_mountp = mp;
663 	efdp->efd_efip = efip;
664 	efdp->efd_format.efd_nextents = nextents;
665 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
666 
667 	return (efdp);
668 }
669