xref: /linux/fs/xfs/xfs_extfree_item.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
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 void
63 xfs_efi_item_free(xfs_efi_log_item_t *efip)
64 {
65 	int nexts = efip->efi_format.efi_nextents;
66 
67 	if (nexts > XFS_EFI_MAX_FAST_EXTENTS) {
68 		kmem_free(efip, sizeof(xfs_efi_log_item_t) +
69 				(nexts - 1) * sizeof(xfs_extent_t));
70 	} else {
71 		kmem_zone_free(xfs_efi_zone, efip);
72 	}
73 }
74 
75 /*
76  * This returns the number of iovecs needed to log the given efi item.
77  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
78  * structure.
79  */
80 /*ARGSUSED*/
81 STATIC uint
82 xfs_efi_item_size(xfs_efi_log_item_t *efip)
83 {
84 	return 1;
85 }
86 
87 /*
88  * This is called to fill in the vector of log iovecs for the
89  * given efi log item. We use only 1 iovec, and we point that
90  * at the efi_log_format structure embedded in the efi item.
91  * It is at this point that we assert that all of the extent
92  * slots in the efi item have been filled.
93  */
94 STATIC void
95 xfs_efi_item_format(xfs_efi_log_item_t	*efip,
96 		    xfs_log_iovec_t	*log_vector)
97 {
98 	uint	size;
99 
100 	ASSERT(efip->efi_next_extent == efip->efi_format.efi_nextents);
101 
102 	efip->efi_format.efi_type = XFS_LI_EFI;
103 
104 	size = sizeof(xfs_efi_log_format_t);
105 	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
106 	efip->efi_format.efi_size = 1;
107 
108 	log_vector->i_addr = (xfs_caddr_t)&(efip->efi_format);
109 	log_vector->i_len = size;
110 	XLOG_VEC_SET_TYPE(log_vector, XLOG_REG_TYPE_EFI_FORMAT);
111 	ASSERT(size >= sizeof(xfs_efi_log_format_t));
112 }
113 
114 
115 /*
116  * Pinning has no meaning for an efi item, so just return.
117  */
118 /*ARGSUSED*/
119 STATIC void
120 xfs_efi_item_pin(xfs_efi_log_item_t *efip)
121 {
122 	return;
123 }
124 
125 
126 /*
127  * While EFIs cannot really be pinned, the unpin operation is the
128  * last place at which the EFI is manipulated during a transaction.
129  * Here we coordinate with xfs_efi_cancel() to determine who gets to
130  * free the EFI.
131  */
132 /*ARGSUSED*/
133 STATIC void
134 xfs_efi_item_unpin(xfs_efi_log_item_t *efip, int stale)
135 {
136 	xfs_mount_t	*mp;
137 	SPLDECL(s);
138 
139 	mp = efip->efi_item.li_mountp;
140 	AIL_LOCK(mp, s);
141 	if (efip->efi_flags & XFS_EFI_CANCELED) {
142 		/*
143 		 * xfs_trans_delete_ail() drops the AIL lock.
144 		 */
145 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
146 		xfs_efi_item_free(efip);
147 	} else {
148 		efip->efi_flags |= XFS_EFI_COMMITTED;
149 		AIL_UNLOCK(mp, s);
150 	}
151 }
152 
153 /*
154  * like unpin only we have to also clear the xaction descriptor
155  * pointing the log item if we free the item.  This routine duplicates
156  * unpin because efi_flags is protected by the AIL lock.  Freeing
157  * the descriptor and then calling unpin would force us to drop the AIL
158  * lock which would open up a race condition.
159  */
160 STATIC void
161 xfs_efi_item_unpin_remove(xfs_efi_log_item_t *efip, xfs_trans_t *tp)
162 {
163 	xfs_mount_t	*mp;
164 	xfs_log_item_desc_t	*lidp;
165 	SPLDECL(s);
166 
167 	mp = efip->efi_item.li_mountp;
168 	AIL_LOCK(mp, s);
169 	if (efip->efi_flags & XFS_EFI_CANCELED) {
170 		/*
171 		 * free the xaction descriptor pointing to this item
172 		 */
173 		lidp = xfs_trans_find_item(tp, (xfs_log_item_t *) efip);
174 		xfs_trans_free_item(tp, lidp);
175 		/*
176 		 * pull the item off the AIL.
177 		 * xfs_trans_delete_ail() drops the AIL lock.
178 		 */
179 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
180 		xfs_efi_item_free(efip);
181 	} else {
182 		efip->efi_flags |= XFS_EFI_COMMITTED;
183 		AIL_UNLOCK(mp, s);
184 	}
185 }
186 
187 /*
188  * Efi items have no locking or pushing.  However, since EFIs are
189  * pulled from the AIL when their corresponding EFDs are committed
190  * to disk, their situation is very similar to being pinned.  Return
191  * XFS_ITEM_PINNED so that the caller will eventually flush the log.
192  * This should help in getting the EFI out of the AIL.
193  */
194 /*ARGSUSED*/
195 STATIC uint
196 xfs_efi_item_trylock(xfs_efi_log_item_t *efip)
197 {
198 	return XFS_ITEM_PINNED;
199 }
200 
201 /*
202  * Efi items have no locking, so just return.
203  */
204 /*ARGSUSED*/
205 STATIC void
206 xfs_efi_item_unlock(xfs_efi_log_item_t *efip)
207 {
208 	if (efip->efi_item.li_flags & XFS_LI_ABORTED)
209 		xfs_efi_item_abort(efip);
210 	return;
211 }
212 
213 /*
214  * The EFI is logged only once and cannot be moved in the log, so
215  * simply return the lsn at which it's been logged.  The canceled
216  * flag is not paid any attention here.  Checking for that is delayed
217  * until the EFI is unpinned.
218  */
219 /*ARGSUSED*/
220 STATIC xfs_lsn_t
221 xfs_efi_item_committed(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
222 {
223 	return lsn;
224 }
225 
226 /*
227  * This is called when the transaction logging the EFI is aborted.
228  * Free up the EFI and return.  No need to clean up the slot for
229  * the item in the transaction.  That was done by the unpin code
230  * which is called prior to this routine in the abort/fs-shutdown path.
231  */
232 STATIC void
233 xfs_efi_item_abort(xfs_efi_log_item_t *efip)
234 {
235 	xfs_efi_item_free(efip);
236 }
237 
238 /*
239  * There isn't much you can do to push on an efi item.  It is simply
240  * stuck waiting for all of its corresponding efd items to be
241  * committed to disk.
242  */
243 /*ARGSUSED*/
244 STATIC void
245 xfs_efi_item_push(xfs_efi_log_item_t *efip)
246 {
247 	return;
248 }
249 
250 /*
251  * The EFI dependency tracking op doesn't do squat.  It can't because
252  * it doesn't know where the free extent is coming from.  The dependency
253  * tracking has to be handled by the "enclosing" metadata object.  For
254  * example, for inodes, the inode is locked throughout the extent freeing
255  * so the dependency should be recorded there.
256  */
257 /*ARGSUSED*/
258 STATIC void
259 xfs_efi_item_committing(xfs_efi_log_item_t *efip, xfs_lsn_t lsn)
260 {
261 	return;
262 }
263 
264 /*
265  * This is the ops vector shared by all efi log items.
266  */
267 STATIC struct xfs_item_ops xfs_efi_item_ops = {
268 	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efi_item_size,
269 	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
270 					xfs_efi_item_format,
271 	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efi_item_pin,
272 	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efi_item_unpin,
273 	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t *))
274 					xfs_efi_item_unpin_remove,
275 	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efi_item_trylock,
276 	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efi_item_unlock,
277 	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
278 					xfs_efi_item_committed,
279 	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efi_item_push,
280 	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efi_item_abort,
281 	.iop_pushbuf	= NULL,
282 	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
283 					xfs_efi_item_committing
284 };
285 
286 
287 /*
288  * Allocate and initialize an efi item with the given number of extents.
289  */
290 xfs_efi_log_item_t *
291 xfs_efi_init(xfs_mount_t	*mp,
292 	     uint		nextents)
293 
294 {
295 	xfs_efi_log_item_t	*efip;
296 	uint			size;
297 
298 	ASSERT(nextents > 0);
299 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
300 		size = (uint)(sizeof(xfs_efi_log_item_t) +
301 			((nextents - 1) * sizeof(xfs_extent_t)));
302 		efip = (xfs_efi_log_item_t*)kmem_zalloc(size, KM_SLEEP);
303 	} else {
304 		efip = (xfs_efi_log_item_t*)kmem_zone_zalloc(xfs_efi_zone,
305 							     KM_SLEEP);
306 	}
307 
308 	efip->efi_item.li_type = XFS_LI_EFI;
309 	efip->efi_item.li_ops = &xfs_efi_item_ops;
310 	efip->efi_item.li_mountp = mp;
311 	efip->efi_format.efi_nextents = nextents;
312 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
313 
314 	return (efip);
315 }
316 
317 /*
318  * This is called by the efd item code below to release references to
319  * the given efi item.  Each efd calls this with the number of
320  * extents that it has logged, and when the sum of these reaches
321  * the total number of extents logged by this efi item we can free
322  * the efi item.
323  *
324  * Freeing the efi item requires that we remove it from the AIL.
325  * We'll use the AIL lock to protect our counters as well as
326  * the removal from the AIL.
327  */
328 void
329 xfs_efi_release(xfs_efi_log_item_t	*efip,
330 		uint			nextents)
331 {
332 	xfs_mount_t	*mp;
333 	int		extents_left;
334 	SPLDECL(s);
335 
336 	mp = efip->efi_item.li_mountp;
337 	ASSERT(efip->efi_next_extent > 0);
338 	ASSERT(efip->efi_flags & XFS_EFI_COMMITTED);
339 
340 	AIL_LOCK(mp, s);
341 	ASSERT(efip->efi_next_extent >= nextents);
342 	efip->efi_next_extent -= nextents;
343 	extents_left = efip->efi_next_extent;
344 	if (extents_left == 0) {
345 		/*
346 		 * xfs_trans_delete_ail() drops the AIL lock.
347 		 */
348 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
349 		xfs_efi_item_free(efip);
350 	} else {
351 		AIL_UNLOCK(mp, s);
352 	}
353 }
354 
355 /*
356  * This is called when the transaction that should be committing the
357  * EFD corresponding to the given EFI is aborted.  The committed and
358  * canceled flags are used to coordinate the freeing of the EFI and
359  * the references by the transaction that committed it.
360  */
361 STATIC void
362 xfs_efi_cancel(
363 	xfs_efi_log_item_t	*efip)
364 {
365 	xfs_mount_t	*mp;
366 	SPLDECL(s);
367 
368 	mp = efip->efi_item.li_mountp;
369 	AIL_LOCK(mp, s);
370 	if (efip->efi_flags & XFS_EFI_COMMITTED) {
371 		/*
372 		 * xfs_trans_delete_ail() drops the AIL lock.
373 		 */
374 		xfs_trans_delete_ail(mp, (xfs_log_item_t *)efip, s);
375 		xfs_efi_item_free(efip);
376 	} else {
377 		efip->efi_flags |= XFS_EFI_CANCELED;
378 		AIL_UNLOCK(mp, s);
379 	}
380 }
381 
382 STATIC void
383 xfs_efd_item_free(xfs_efd_log_item_t *efdp)
384 {
385 	int nexts = efdp->efd_format.efd_nextents;
386 
387 	if (nexts > XFS_EFD_MAX_FAST_EXTENTS) {
388 		kmem_free(efdp, sizeof(xfs_efd_log_item_t) +
389 				(nexts - 1) * sizeof(xfs_extent_t));
390 	} else {
391 		kmem_zone_free(xfs_efd_zone, efdp);
392 	}
393 }
394 
395 /*
396  * This returns the number of iovecs needed to log the given efd item.
397  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
398  * structure.
399  */
400 /*ARGSUSED*/
401 STATIC uint
402 xfs_efd_item_size(xfs_efd_log_item_t *efdp)
403 {
404 	return 1;
405 }
406 
407 /*
408  * This is called to fill in the vector of log iovecs for the
409  * given efd log item. We use only 1 iovec, and we point that
410  * at the efd_log_format structure embedded in the efd item.
411  * It is at this point that we assert that all of the extent
412  * slots in the efd item have been filled.
413  */
414 STATIC void
415 xfs_efd_item_format(xfs_efd_log_item_t	*efdp,
416 		    xfs_log_iovec_t	*log_vector)
417 {
418 	uint	size;
419 
420 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
421 
422 	efdp->efd_format.efd_type = XFS_LI_EFD;
423 
424 	size = sizeof(xfs_efd_log_format_t);
425 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
426 	efdp->efd_format.efd_size = 1;
427 
428 	log_vector->i_addr = (xfs_caddr_t)&(efdp->efd_format);
429 	log_vector->i_len = size;
430 	XLOG_VEC_SET_TYPE(log_vector, XLOG_REG_TYPE_EFD_FORMAT);
431 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
432 }
433 
434 
435 /*
436  * Pinning has no meaning for an efd item, so just return.
437  */
438 /*ARGSUSED*/
439 STATIC void
440 xfs_efd_item_pin(xfs_efd_log_item_t *efdp)
441 {
442 	return;
443 }
444 
445 
446 /*
447  * Since pinning has no meaning for an efd item, unpinning does
448  * not either.
449  */
450 /*ARGSUSED*/
451 STATIC void
452 xfs_efd_item_unpin(xfs_efd_log_item_t *efdp, int stale)
453 {
454 	return;
455 }
456 
457 /*ARGSUSED*/
458 STATIC void
459 xfs_efd_item_unpin_remove(xfs_efd_log_item_t *efdp, xfs_trans_t *tp)
460 {
461 	return;
462 }
463 
464 /*
465  * Efd items have no locking, so just return success.
466  */
467 /*ARGSUSED*/
468 STATIC uint
469 xfs_efd_item_trylock(xfs_efd_log_item_t *efdp)
470 {
471 	return XFS_ITEM_LOCKED;
472 }
473 
474 /*
475  * Efd items have no locking or pushing, so return failure
476  * so that the caller doesn't bother with us.
477  */
478 /*ARGSUSED*/
479 STATIC void
480 xfs_efd_item_unlock(xfs_efd_log_item_t *efdp)
481 {
482 	if (efdp->efd_item.li_flags & XFS_LI_ABORTED)
483 		xfs_efd_item_abort(efdp);
484 	return;
485 }
486 
487 /*
488  * When the efd item is committed to disk, all we need to do
489  * is delete our reference to our partner efi item and then
490  * free ourselves.  Since we're freeing ourselves we must
491  * return -1 to keep the transaction code from further referencing
492  * this item.
493  */
494 /*ARGSUSED*/
495 STATIC xfs_lsn_t
496 xfs_efd_item_committed(xfs_efd_log_item_t *efdp, xfs_lsn_t lsn)
497 {
498 	/*
499 	 * If we got a log I/O error, it's always the case that the LR with the
500 	 * EFI got unpinned and freed before the EFD got aborted.
501 	 */
502 	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
503 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
504 
505 	xfs_efd_item_free(efdp);
506 	return (xfs_lsn_t)-1;
507 }
508 
509 /*
510  * The transaction of which this EFD is a part has been aborted.
511  * Inform its companion EFI of this fact and then clean up after
512  * ourselves.  No need to clean up the slot for the item in the
513  * transaction.  That was done by the unpin code which is called
514  * prior to this routine in the abort/fs-shutdown path.
515  */
516 STATIC void
517 xfs_efd_item_abort(xfs_efd_log_item_t *efdp)
518 {
519 	/*
520 	 * If we got a log I/O error, it's always the case that the LR with the
521 	 * EFI got unpinned and freed before the EFD got aborted. So don't
522 	 * reference the EFI at all in that case.
523 	 */
524 	if ((efdp->efd_item.li_flags & XFS_LI_ABORTED) == 0)
525 		xfs_efi_cancel(efdp->efd_efip);
526 
527 	xfs_efd_item_free(efdp);
528 }
529 
530 /*
531  * There isn't much you can do to push on an efd item.  It is simply
532  * stuck waiting for the log to be flushed to disk.
533  */
534 /*ARGSUSED*/
535 STATIC void
536 xfs_efd_item_push(xfs_efd_log_item_t *efdp)
537 {
538 	return;
539 }
540 
541 /*
542  * The EFD dependency tracking op doesn't do squat.  It can't because
543  * it doesn't know where the free extent is coming from.  The dependency
544  * tracking has to be handled by the "enclosing" metadata object.  For
545  * example, for inodes, the inode is locked throughout the extent freeing
546  * so the dependency should be recorded there.
547  */
548 /*ARGSUSED*/
549 STATIC void
550 xfs_efd_item_committing(xfs_efd_log_item_t *efip, xfs_lsn_t lsn)
551 {
552 	return;
553 }
554 
555 /*
556  * This is the ops vector shared by all efd log items.
557  */
558 STATIC struct xfs_item_ops xfs_efd_item_ops = {
559 	.iop_size	= (uint(*)(xfs_log_item_t*))xfs_efd_item_size,
560 	.iop_format	= (void(*)(xfs_log_item_t*, xfs_log_iovec_t*))
561 					xfs_efd_item_format,
562 	.iop_pin	= (void(*)(xfs_log_item_t*))xfs_efd_item_pin,
563 	.iop_unpin	= (void(*)(xfs_log_item_t*, int))xfs_efd_item_unpin,
564 	.iop_unpin_remove = (void(*)(xfs_log_item_t*, xfs_trans_t*))
565 					xfs_efd_item_unpin_remove,
566 	.iop_trylock	= (uint(*)(xfs_log_item_t*))xfs_efd_item_trylock,
567 	.iop_unlock	= (void(*)(xfs_log_item_t*))xfs_efd_item_unlock,
568 	.iop_committed	= (xfs_lsn_t(*)(xfs_log_item_t*, xfs_lsn_t))
569 					xfs_efd_item_committed,
570 	.iop_push	= (void(*)(xfs_log_item_t*))xfs_efd_item_push,
571 	.iop_abort	= (void(*)(xfs_log_item_t*))xfs_efd_item_abort,
572 	.iop_pushbuf	= NULL,
573 	.iop_committing = (void(*)(xfs_log_item_t*, xfs_lsn_t))
574 					xfs_efd_item_committing
575 };
576 
577 
578 /*
579  * Allocate and initialize an efd item with the given number of extents.
580  */
581 xfs_efd_log_item_t *
582 xfs_efd_init(xfs_mount_t	*mp,
583 	     xfs_efi_log_item_t	*efip,
584 	     uint		nextents)
585 
586 {
587 	xfs_efd_log_item_t	*efdp;
588 	uint			size;
589 
590 	ASSERT(nextents > 0);
591 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
592 		size = (uint)(sizeof(xfs_efd_log_item_t) +
593 			((nextents - 1) * sizeof(xfs_extent_t)));
594 		efdp = (xfs_efd_log_item_t*)kmem_zalloc(size, KM_SLEEP);
595 	} else {
596 		efdp = (xfs_efd_log_item_t*)kmem_zone_zalloc(xfs_efd_zone,
597 							     KM_SLEEP);
598 	}
599 
600 	efdp->efd_item.li_type = XFS_LI_EFD;
601 	efdp->efd_item.li_ops = &xfs_efd_item_ops;
602 	efdp->efd_item.li_mountp = mp;
603 	efdp->efd_efip = efip;
604 	efdp->efd_format.efd_nextents = nextents;
605 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
606 
607 	return (efdp);
608 }
609