xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision b595076a)
1 /*
2  * Copyright (c) 2000-2001,2005 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_types.h"
21 #include "xfs_log.h"
22 #include "xfs_inum.h"
23 #include "xfs_trans.h"
24 #include "xfs_buf_item.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_trans_priv.h"
29 #include "xfs_extfree_item.h"
30 
31 
32 kmem_zone_t	*xfs_efi_zone;
33 kmem_zone_t	*xfs_efd_zone;
34 
35 static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
36 {
37 	return container_of(lip, struct xfs_efi_log_item, efi_item);
38 }
39 
40 void
41 xfs_efi_item_free(
42 	struct xfs_efi_log_item	*efip)
43 {
44 	if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
45 		kmem_free(efip);
46 	else
47 		kmem_zone_free(xfs_efi_zone, efip);
48 }
49 
50 /*
51  * This returns the number of iovecs needed to log the given efi item.
52  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
53  * structure.
54  */
55 STATIC uint
56 xfs_efi_item_size(
57 	struct xfs_log_item	*lip)
58 {
59 	return 1;
60 }
61 
62 /*
63  * This is called to fill in the vector of log iovecs for the
64  * given efi log item. We use only 1 iovec, and we point that
65  * at the efi_log_format structure embedded in the efi item.
66  * It is at this point that we assert that all of the extent
67  * slots in the efi item have been filled.
68  */
69 STATIC void
70 xfs_efi_item_format(
71 	struct xfs_log_item	*lip,
72 	struct xfs_log_iovec	*log_vector)
73 {
74 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
75 	uint			size;
76 
77 	ASSERT(efip->efi_next_extent == efip->efi_format.efi_nextents);
78 
79 	efip->efi_format.efi_type = XFS_LI_EFI;
80 
81 	size = sizeof(xfs_efi_log_format_t);
82 	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
83 	efip->efi_format.efi_size = 1;
84 
85 	log_vector->i_addr = &efip->efi_format;
86 	log_vector->i_len = size;
87 	log_vector->i_type = XLOG_REG_TYPE_EFI_FORMAT;
88 	ASSERT(size >= sizeof(xfs_efi_log_format_t));
89 }
90 
91 
92 /*
93  * Pinning has no meaning for an efi item, so just return.
94  */
95 STATIC void
96 xfs_efi_item_pin(
97 	struct xfs_log_item	*lip)
98 {
99 }
100 
101 /*
102  * While EFIs cannot really be pinned, the unpin operation is the
103  * last place at which the EFI is manipulated during a transaction.
104  * Here we coordinate with xfs_efi_cancel() to determine who gets to
105  * free the EFI.
106  */
107 STATIC void
108 xfs_efi_item_unpin(
109 	struct xfs_log_item	*lip,
110 	int			remove)
111 {
112 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
113 	struct xfs_ail		*ailp = lip->li_ailp;
114 
115 	spin_lock(&ailp->xa_lock);
116 	if (efip->efi_flags & XFS_EFI_CANCELED) {
117 		if (remove)
118 			xfs_trans_del_item(lip);
119 
120 		/* xfs_trans_ail_delete() drops the AIL lock. */
121 		xfs_trans_ail_delete(ailp, lip);
122 		xfs_efi_item_free(efip);
123 	} else {
124 		efip->efi_flags |= XFS_EFI_COMMITTED;
125 		spin_unlock(&ailp->xa_lock);
126 	}
127 }
128 
129 /*
130  * Efi items have no locking or pushing.  However, since EFIs are
131  * pulled from the AIL when their corresponding EFDs are committed
132  * to disk, their situation is very similar to being pinned.  Return
133  * XFS_ITEM_PINNED so that the caller will eventually flush the log.
134  * This should help in getting the EFI out of the AIL.
135  */
136 STATIC uint
137 xfs_efi_item_trylock(
138 	struct xfs_log_item	*lip)
139 {
140 	return XFS_ITEM_PINNED;
141 }
142 
143 /*
144  * Efi items have no locking, so just return.
145  */
146 STATIC void
147 xfs_efi_item_unlock(
148 	struct xfs_log_item	*lip)
149 {
150 	if (lip->li_flags & XFS_LI_ABORTED)
151 		xfs_efi_item_free(EFI_ITEM(lip));
152 }
153 
154 /*
155  * The EFI is logged only once and cannot be moved in the log, so
156  * simply return the lsn at which it's been logged.  The canceled
157  * flag is not paid any attention here.  Checking for that is delayed
158  * until the EFI is unpinned.
159  */
160 STATIC xfs_lsn_t
161 xfs_efi_item_committed(
162 	struct xfs_log_item	*lip,
163 	xfs_lsn_t		lsn)
164 {
165 	return lsn;
166 }
167 
168 /*
169  * There isn't much you can do to push on an efi item.  It is simply
170  * stuck waiting for all of its corresponding efd items to be
171  * committed to disk.
172  */
173 STATIC void
174 xfs_efi_item_push(
175 	struct xfs_log_item	*lip)
176 {
177 }
178 
179 /*
180  * The EFI dependency tracking op doesn't do squat.  It can't because
181  * it doesn't know where the free extent is coming from.  The dependency
182  * tracking has to be handled by the "enclosing" metadata object.  For
183  * example, for inodes, the inode is locked throughout the extent freeing
184  * so the dependency should be recorded there.
185  */
186 STATIC void
187 xfs_efi_item_committing(
188 	struct xfs_log_item	*lip,
189 	xfs_lsn_t		lsn)
190 {
191 }
192 
193 /*
194  * This is the ops vector shared by all efi log items.
195  */
196 static struct xfs_item_ops xfs_efi_item_ops = {
197 	.iop_size	= xfs_efi_item_size,
198 	.iop_format	= xfs_efi_item_format,
199 	.iop_pin	= xfs_efi_item_pin,
200 	.iop_unpin	= xfs_efi_item_unpin,
201 	.iop_trylock	= xfs_efi_item_trylock,
202 	.iop_unlock	= xfs_efi_item_unlock,
203 	.iop_committed	= xfs_efi_item_committed,
204 	.iop_push	= xfs_efi_item_push,
205 	.iop_committing = xfs_efi_item_committing
206 };
207 
208 
209 /*
210  * Allocate and initialize an efi item with the given number of extents.
211  */
212 struct xfs_efi_log_item *
213 xfs_efi_init(
214 	struct xfs_mount	*mp,
215 	uint			nextents)
216 
217 {
218 	struct xfs_efi_log_item	*efip;
219 	uint			size;
220 
221 	ASSERT(nextents > 0);
222 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
223 		size = (uint)(sizeof(xfs_efi_log_item_t) +
224 			((nextents - 1) * sizeof(xfs_extent_t)));
225 		efip = kmem_zalloc(size, KM_SLEEP);
226 	} else {
227 		efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
228 	}
229 
230 	xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
231 	efip->efi_format.efi_nextents = nextents;
232 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
233 
234 	return efip;
235 }
236 
237 /*
238  * Copy an EFI format buffer from the given buf, and into the destination
239  * EFI format structure.
240  * The given buffer can be in 32 bit or 64 bit form (which has different padding),
241  * one of which will be the native format for this kernel.
242  * It will handle the conversion of formats if necessary.
243  */
244 int
245 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
246 {
247 	xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
248 	uint i;
249 	uint len = sizeof(xfs_efi_log_format_t) +
250 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
251 	uint len32 = sizeof(xfs_efi_log_format_32_t) +
252 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
253 	uint len64 = sizeof(xfs_efi_log_format_64_t) +
254 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
255 
256 	if (buf->i_len == len) {
257 		memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
258 		return 0;
259 	} else if (buf->i_len == len32) {
260 		xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
261 
262 		dst_efi_fmt->efi_type     = src_efi_fmt_32->efi_type;
263 		dst_efi_fmt->efi_size     = src_efi_fmt_32->efi_size;
264 		dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
265 		dst_efi_fmt->efi_id       = src_efi_fmt_32->efi_id;
266 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
267 			dst_efi_fmt->efi_extents[i].ext_start =
268 				src_efi_fmt_32->efi_extents[i].ext_start;
269 			dst_efi_fmt->efi_extents[i].ext_len =
270 				src_efi_fmt_32->efi_extents[i].ext_len;
271 		}
272 		return 0;
273 	} else if (buf->i_len == len64) {
274 		xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
275 
276 		dst_efi_fmt->efi_type     = src_efi_fmt_64->efi_type;
277 		dst_efi_fmt->efi_size     = src_efi_fmt_64->efi_size;
278 		dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
279 		dst_efi_fmt->efi_id       = src_efi_fmt_64->efi_id;
280 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
281 			dst_efi_fmt->efi_extents[i].ext_start =
282 				src_efi_fmt_64->efi_extents[i].ext_start;
283 			dst_efi_fmt->efi_extents[i].ext_len =
284 				src_efi_fmt_64->efi_extents[i].ext_len;
285 		}
286 		return 0;
287 	}
288 	return EFSCORRUPTED;
289 }
290 
291 /*
292  * This is called by the efd item code below to release references to
293  * the given efi item.  Each efd calls this with the number of
294  * extents that it has logged, and when the sum of these reaches
295  * the total number of extents logged by this efi item we can free
296  * the efi item.
297  *
298  * Freeing the efi item requires that we remove it from the AIL.
299  * We'll use the AIL lock to protect our counters as well as
300  * the removal from the AIL.
301  */
302 void
303 xfs_efi_release(xfs_efi_log_item_t	*efip,
304 		uint			nextents)
305 {
306 	struct xfs_ail		*ailp = efip->efi_item.li_ailp;
307 	int			extents_left;
308 
309 	ASSERT(efip->efi_next_extent > 0);
310 	ASSERT(efip->efi_flags & XFS_EFI_COMMITTED);
311 
312 	spin_lock(&ailp->xa_lock);
313 	ASSERT(efip->efi_next_extent >= nextents);
314 	efip->efi_next_extent -= nextents;
315 	extents_left = efip->efi_next_extent;
316 	if (extents_left == 0) {
317 		/* xfs_trans_ail_delete() drops the AIL lock. */
318 		xfs_trans_ail_delete(ailp, (xfs_log_item_t *)efip);
319 		xfs_efi_item_free(efip);
320 	} else {
321 		spin_unlock(&ailp->xa_lock);
322 	}
323 }
324 
325 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
326 {
327 	return container_of(lip, struct xfs_efd_log_item, efd_item);
328 }
329 
330 STATIC void
331 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
332 {
333 	if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
334 		kmem_free(efdp);
335 	else
336 		kmem_zone_free(xfs_efd_zone, efdp);
337 }
338 
339 /*
340  * This returns the number of iovecs needed to log the given efd item.
341  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
342  * structure.
343  */
344 STATIC uint
345 xfs_efd_item_size(
346 	struct xfs_log_item	*lip)
347 {
348 	return 1;
349 }
350 
351 /*
352  * This is called to fill in the vector of log iovecs for the
353  * given efd log item. We use only 1 iovec, and we point that
354  * at the efd_log_format structure embedded in the efd item.
355  * It is at this point that we assert that all of the extent
356  * slots in the efd item have been filled.
357  */
358 STATIC void
359 xfs_efd_item_format(
360 	struct xfs_log_item	*lip,
361 	struct xfs_log_iovec	*log_vector)
362 {
363 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
364 	uint			size;
365 
366 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
367 
368 	efdp->efd_format.efd_type = XFS_LI_EFD;
369 
370 	size = sizeof(xfs_efd_log_format_t);
371 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
372 	efdp->efd_format.efd_size = 1;
373 
374 	log_vector->i_addr = &efdp->efd_format;
375 	log_vector->i_len = size;
376 	log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
377 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
378 }
379 
380 /*
381  * Pinning has no meaning for an efd item, so just return.
382  */
383 STATIC void
384 xfs_efd_item_pin(
385 	struct xfs_log_item	*lip)
386 {
387 }
388 
389 /*
390  * Since pinning has no meaning for an efd item, unpinning does
391  * not either.
392  */
393 STATIC void
394 xfs_efd_item_unpin(
395 	struct xfs_log_item	*lip,
396 	int			remove)
397 {
398 }
399 
400 /*
401  * Efd items have no locking, so just return success.
402  */
403 STATIC uint
404 xfs_efd_item_trylock(
405 	struct xfs_log_item	*lip)
406 {
407 	return XFS_ITEM_LOCKED;
408 }
409 
410 /*
411  * Efd items have no locking or pushing, so return failure
412  * so that the caller doesn't bother with us.
413  */
414 STATIC void
415 xfs_efd_item_unlock(
416 	struct xfs_log_item	*lip)
417 {
418 	if (lip->li_flags & XFS_LI_ABORTED)
419 		xfs_efd_item_free(EFD_ITEM(lip));
420 }
421 
422 /*
423  * When the efd item is committed to disk, all we need to do
424  * is delete our reference to our partner efi item and then
425  * free ourselves.  Since we're freeing ourselves we must
426  * return -1 to keep the transaction code from further referencing
427  * this item.
428  */
429 STATIC xfs_lsn_t
430 xfs_efd_item_committed(
431 	struct xfs_log_item	*lip,
432 	xfs_lsn_t		lsn)
433 {
434 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
435 
436 	/*
437 	 * If we got a log I/O error, it's always the case that the LR with the
438 	 * EFI got unpinned and freed before the EFD got aborted.
439 	 */
440 	if (!(lip->li_flags & XFS_LI_ABORTED))
441 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
442 
443 	xfs_efd_item_free(efdp);
444 	return (xfs_lsn_t)-1;
445 }
446 
447 /*
448  * There isn't much you can do to push on an efd item.  It is simply
449  * stuck waiting for the log to be flushed to disk.
450  */
451 STATIC void
452 xfs_efd_item_push(
453 	struct xfs_log_item	*lip)
454 {
455 }
456 
457 /*
458  * The EFD dependency tracking op doesn't do squat.  It can't because
459  * it doesn't know where the free extent is coming from.  The dependency
460  * tracking has to be handled by the "enclosing" metadata object.  For
461  * example, for inodes, the inode is locked throughout the extent freeing
462  * so the dependency should be recorded there.
463  */
464 STATIC void
465 xfs_efd_item_committing(
466 	struct xfs_log_item	*lip,
467 	xfs_lsn_t		lsn)
468 {
469 }
470 
471 /*
472  * This is the ops vector shared by all efd log items.
473  */
474 static struct xfs_item_ops xfs_efd_item_ops = {
475 	.iop_size	= xfs_efd_item_size,
476 	.iop_format	= xfs_efd_item_format,
477 	.iop_pin	= xfs_efd_item_pin,
478 	.iop_unpin	= xfs_efd_item_unpin,
479 	.iop_trylock	= xfs_efd_item_trylock,
480 	.iop_unlock	= xfs_efd_item_unlock,
481 	.iop_committed	= xfs_efd_item_committed,
482 	.iop_push	= xfs_efd_item_push,
483 	.iop_committing = xfs_efd_item_committing
484 };
485 
486 /*
487  * Allocate and initialize an efd item with the given number of extents.
488  */
489 struct xfs_efd_log_item *
490 xfs_efd_init(
491 	struct xfs_mount	*mp,
492 	struct xfs_efi_log_item	*efip,
493 	uint			nextents)
494 
495 {
496 	struct xfs_efd_log_item	*efdp;
497 	uint			size;
498 
499 	ASSERT(nextents > 0);
500 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
501 		size = (uint)(sizeof(xfs_efd_log_item_t) +
502 			((nextents - 1) * sizeof(xfs_extent_t)));
503 		efdp = kmem_zalloc(size, KM_SLEEP);
504 	} else {
505 		efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
506 	}
507 
508 	xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
509 	efdp->efd_efip = efip;
510 	efdp->efd_format.efd_nextents = nextents;
511 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
512 
513 	return efdp;
514 }
515