xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision 95e9fd10)
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_trans.h"
23 #include "xfs_buf_item.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_mount.h"
27 #include "xfs_trans_priv.h"
28 #include "xfs_extfree_item.h"
29 
30 
31 kmem_zone_t	*xfs_efi_zone;
32 kmem_zone_t	*xfs_efd_zone;
33 
34 static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
35 {
36 	return container_of(lip, struct xfs_efi_log_item, efi_item);
37 }
38 
39 void
40 xfs_efi_item_free(
41 	struct xfs_efi_log_item	*efip)
42 {
43 	if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
44 		kmem_free(efip);
45 	else
46 		kmem_zone_free(xfs_efi_zone, efip);
47 }
48 
49 /*
50  * Freeing the efi requires that we remove it from the AIL if it has already
51  * been placed there. However, the EFI may not yet have been placed in the AIL
52  * when called by xfs_efi_release() from EFD processing due to the ordering of
53  * committed vs unpin operations in bulk insert operations. Hence the
54  * test_and_clear_bit(XFS_EFI_COMMITTED) to ensure only the last caller frees
55  * the EFI.
56  */
57 STATIC void
58 __xfs_efi_release(
59 	struct xfs_efi_log_item	*efip)
60 {
61 	struct xfs_ail		*ailp = efip->efi_item.li_ailp;
62 
63 	if (!test_and_clear_bit(XFS_EFI_COMMITTED, &efip->efi_flags)) {
64 		spin_lock(&ailp->xa_lock);
65 		/* xfs_trans_ail_delete() drops the AIL lock. */
66 		xfs_trans_ail_delete(ailp, &efip->efi_item,
67 				     SHUTDOWN_LOG_IO_ERROR);
68 		xfs_efi_item_free(efip);
69 	}
70 }
71 
72 /*
73  * This returns the number of iovecs needed to log the given efi item.
74  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
75  * structure.
76  */
77 STATIC uint
78 xfs_efi_item_size(
79 	struct xfs_log_item	*lip)
80 {
81 	return 1;
82 }
83 
84 /*
85  * This is called to fill in the vector of log iovecs for the
86  * given efi log item. We use only 1 iovec, and we point that
87  * at the efi_log_format structure embedded in the efi item.
88  * It is at this point that we assert that all of the extent
89  * slots in the efi item have been filled.
90  */
91 STATIC void
92 xfs_efi_item_format(
93 	struct xfs_log_item	*lip,
94 	struct xfs_log_iovec	*log_vector)
95 {
96 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
97 	uint			size;
98 
99 	ASSERT(atomic_read(&efip->efi_next_extent) ==
100 				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 = &efip->efi_format;
109 	log_vector->i_len = size;
110 	log_vector->i_type = 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 STATIC void
119 xfs_efi_item_pin(
120 	struct xfs_log_item	*lip)
121 {
122 }
123 
124 /*
125  * While EFIs cannot really be pinned, the unpin operation is the last place at
126  * which the EFI is manipulated during a transaction.  If we are being asked to
127  * remove the EFI it's because the transaction has been cancelled and by
128  * definition that means the EFI cannot be in the AIL so remove it from the
129  * transaction and free it.  Otherwise coordinate with xfs_efi_release() (via
130  * XFS_EFI_COMMITTED) to determine who gets to free the EFI.
131  */
132 STATIC void
133 xfs_efi_item_unpin(
134 	struct xfs_log_item	*lip,
135 	int			remove)
136 {
137 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
138 
139 	if (remove) {
140 		ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
141 		if (lip->li_desc)
142 			xfs_trans_del_item(lip);
143 		xfs_efi_item_free(efip);
144 		return;
145 	}
146 	__xfs_efi_release(efip);
147 }
148 
149 /*
150  * Efi items have no locking or pushing.  However, since EFIs are pulled from
151  * the AIL when their corresponding EFDs are committed to disk, their situation
152  * is very similar to being pinned.  Return XFS_ITEM_PINNED so that the caller
153  * will eventually flush the log.  This should help in getting the EFI out of
154  * the AIL.
155  */
156 STATIC uint
157 xfs_efi_item_push(
158 	struct xfs_log_item	*lip,
159 	struct list_head	*buffer_list)
160 {
161 	return XFS_ITEM_PINNED;
162 }
163 
164 STATIC void
165 xfs_efi_item_unlock(
166 	struct xfs_log_item	*lip)
167 {
168 	if (lip->li_flags & XFS_LI_ABORTED)
169 		xfs_efi_item_free(EFI_ITEM(lip));
170 }
171 
172 /*
173  * The EFI is logged only once and cannot be moved in the log, so simply return
174  * the lsn at which it's been logged.  For bulk transaction committed
175  * processing, the EFI may be processed but not yet unpinned prior to the EFD
176  * being processed. Set the XFS_EFI_COMMITTED flag so this case can be detected
177  * when processing the EFD.
178  */
179 STATIC xfs_lsn_t
180 xfs_efi_item_committed(
181 	struct xfs_log_item	*lip,
182 	xfs_lsn_t		lsn)
183 {
184 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
185 
186 	set_bit(XFS_EFI_COMMITTED, &efip->efi_flags);
187 	return lsn;
188 }
189 
190 /*
191  * The EFI dependency tracking op doesn't do squat.  It can't because
192  * it doesn't know where the free extent is coming from.  The dependency
193  * tracking has to be handled by the "enclosing" metadata object.  For
194  * example, for inodes, the inode is locked throughout the extent freeing
195  * so the dependency should be recorded there.
196  */
197 STATIC void
198 xfs_efi_item_committing(
199 	struct xfs_log_item	*lip,
200 	xfs_lsn_t		lsn)
201 {
202 }
203 
204 /*
205  * This is the ops vector shared by all efi log items.
206  */
207 static const struct xfs_item_ops xfs_efi_item_ops = {
208 	.iop_size	= xfs_efi_item_size,
209 	.iop_format	= xfs_efi_item_format,
210 	.iop_pin	= xfs_efi_item_pin,
211 	.iop_unpin	= xfs_efi_item_unpin,
212 	.iop_unlock	= xfs_efi_item_unlock,
213 	.iop_committed	= xfs_efi_item_committed,
214 	.iop_push	= xfs_efi_item_push,
215 	.iop_committing = xfs_efi_item_committing
216 };
217 
218 
219 /*
220  * Allocate and initialize an efi item with the given number of extents.
221  */
222 struct xfs_efi_log_item *
223 xfs_efi_init(
224 	struct xfs_mount	*mp,
225 	uint			nextents)
226 
227 {
228 	struct xfs_efi_log_item	*efip;
229 	uint			size;
230 
231 	ASSERT(nextents > 0);
232 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
233 		size = (uint)(sizeof(xfs_efi_log_item_t) +
234 			((nextents - 1) * sizeof(xfs_extent_t)));
235 		efip = kmem_zalloc(size, KM_SLEEP);
236 	} else {
237 		efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
238 	}
239 
240 	xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
241 	efip->efi_format.efi_nextents = nextents;
242 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
243 	atomic_set(&efip->efi_next_extent, 0);
244 
245 	return efip;
246 }
247 
248 /*
249  * Copy an EFI format buffer from the given buf, and into the destination
250  * EFI format structure.
251  * The given buffer can be in 32 bit or 64 bit form (which has different padding),
252  * one of which will be the native format for this kernel.
253  * It will handle the conversion of formats if necessary.
254  */
255 int
256 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
257 {
258 	xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
259 	uint i;
260 	uint len = sizeof(xfs_efi_log_format_t) +
261 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
262 	uint len32 = sizeof(xfs_efi_log_format_32_t) +
263 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
264 	uint len64 = sizeof(xfs_efi_log_format_64_t) +
265 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
266 
267 	if (buf->i_len == len) {
268 		memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
269 		return 0;
270 	} else if (buf->i_len == len32) {
271 		xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
272 
273 		dst_efi_fmt->efi_type     = src_efi_fmt_32->efi_type;
274 		dst_efi_fmt->efi_size     = src_efi_fmt_32->efi_size;
275 		dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
276 		dst_efi_fmt->efi_id       = src_efi_fmt_32->efi_id;
277 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
278 			dst_efi_fmt->efi_extents[i].ext_start =
279 				src_efi_fmt_32->efi_extents[i].ext_start;
280 			dst_efi_fmt->efi_extents[i].ext_len =
281 				src_efi_fmt_32->efi_extents[i].ext_len;
282 		}
283 		return 0;
284 	} else if (buf->i_len == len64) {
285 		xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
286 
287 		dst_efi_fmt->efi_type     = src_efi_fmt_64->efi_type;
288 		dst_efi_fmt->efi_size     = src_efi_fmt_64->efi_size;
289 		dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
290 		dst_efi_fmt->efi_id       = src_efi_fmt_64->efi_id;
291 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
292 			dst_efi_fmt->efi_extents[i].ext_start =
293 				src_efi_fmt_64->efi_extents[i].ext_start;
294 			dst_efi_fmt->efi_extents[i].ext_len =
295 				src_efi_fmt_64->efi_extents[i].ext_len;
296 		}
297 		return 0;
298 	}
299 	return EFSCORRUPTED;
300 }
301 
302 /*
303  * This is called by the efd item code below to release references to the given
304  * efi item.  Each efd calls this with the number of extents that it has
305  * logged, and when the sum of these reaches the total number of extents logged
306  * by this efi item we can free the efi item.
307  */
308 void
309 xfs_efi_release(xfs_efi_log_item_t	*efip,
310 		uint			nextents)
311 {
312 	ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
313 	if (atomic_sub_and_test(nextents, &efip->efi_next_extent))
314 		__xfs_efi_release(efip);
315 }
316 
317 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
318 {
319 	return container_of(lip, struct xfs_efd_log_item, efd_item);
320 }
321 
322 STATIC void
323 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
324 {
325 	if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
326 		kmem_free(efdp);
327 	else
328 		kmem_zone_free(xfs_efd_zone, efdp);
329 }
330 
331 /*
332  * This returns the number of iovecs needed to log the given efd item.
333  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
334  * structure.
335  */
336 STATIC uint
337 xfs_efd_item_size(
338 	struct xfs_log_item	*lip)
339 {
340 	return 1;
341 }
342 
343 /*
344  * This is called to fill in the vector of log iovecs for the
345  * given efd log item. We use only 1 iovec, and we point that
346  * at the efd_log_format structure embedded in the efd item.
347  * It is at this point that we assert that all of the extent
348  * slots in the efd item have been filled.
349  */
350 STATIC void
351 xfs_efd_item_format(
352 	struct xfs_log_item	*lip,
353 	struct xfs_log_iovec	*log_vector)
354 {
355 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
356 	uint			size;
357 
358 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
359 
360 	efdp->efd_format.efd_type = XFS_LI_EFD;
361 
362 	size = sizeof(xfs_efd_log_format_t);
363 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
364 	efdp->efd_format.efd_size = 1;
365 
366 	log_vector->i_addr = &efdp->efd_format;
367 	log_vector->i_len = size;
368 	log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
369 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
370 }
371 
372 /*
373  * Pinning has no meaning for an efd item, so just return.
374  */
375 STATIC void
376 xfs_efd_item_pin(
377 	struct xfs_log_item	*lip)
378 {
379 }
380 
381 /*
382  * Since pinning has no meaning for an efd item, unpinning does
383  * not either.
384  */
385 STATIC void
386 xfs_efd_item_unpin(
387 	struct xfs_log_item	*lip,
388 	int			remove)
389 {
390 }
391 
392 /*
393  * There isn't much you can do to push on an efd item.  It is simply stuck
394  * waiting for the log to be flushed to disk.
395  */
396 STATIC uint
397 xfs_efd_item_push(
398 	struct xfs_log_item	*lip,
399 	struct list_head	*buffer_list)
400 {
401 	return XFS_ITEM_PINNED;
402 }
403 
404 STATIC void
405 xfs_efd_item_unlock(
406 	struct xfs_log_item	*lip)
407 {
408 	if (lip->li_flags & XFS_LI_ABORTED)
409 		xfs_efd_item_free(EFD_ITEM(lip));
410 }
411 
412 /*
413  * When the efd item is committed to disk, all we need to do
414  * is delete our reference to our partner efi item and then
415  * free ourselves.  Since we're freeing ourselves we must
416  * return -1 to keep the transaction code from further referencing
417  * this item.
418  */
419 STATIC xfs_lsn_t
420 xfs_efd_item_committed(
421 	struct xfs_log_item	*lip,
422 	xfs_lsn_t		lsn)
423 {
424 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
425 
426 	/*
427 	 * If we got a log I/O error, it's always the case that the LR with the
428 	 * EFI got unpinned and freed before the EFD got aborted.
429 	 */
430 	if (!(lip->li_flags & XFS_LI_ABORTED))
431 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
432 
433 	xfs_efd_item_free(efdp);
434 	return (xfs_lsn_t)-1;
435 }
436 
437 /*
438  * The EFD dependency tracking op doesn't do squat.  It can't because
439  * it doesn't know where the free extent is coming from.  The dependency
440  * tracking has to be handled by the "enclosing" metadata object.  For
441  * example, for inodes, the inode is locked throughout the extent freeing
442  * so the dependency should be recorded there.
443  */
444 STATIC void
445 xfs_efd_item_committing(
446 	struct xfs_log_item	*lip,
447 	xfs_lsn_t		lsn)
448 {
449 }
450 
451 /*
452  * This is the ops vector shared by all efd log items.
453  */
454 static const struct xfs_item_ops xfs_efd_item_ops = {
455 	.iop_size	= xfs_efd_item_size,
456 	.iop_format	= xfs_efd_item_format,
457 	.iop_pin	= xfs_efd_item_pin,
458 	.iop_unpin	= xfs_efd_item_unpin,
459 	.iop_unlock	= xfs_efd_item_unlock,
460 	.iop_committed	= xfs_efd_item_committed,
461 	.iop_push	= xfs_efd_item_push,
462 	.iop_committing = xfs_efd_item_committing
463 };
464 
465 /*
466  * Allocate and initialize an efd item with the given number of extents.
467  */
468 struct xfs_efd_log_item *
469 xfs_efd_init(
470 	struct xfs_mount	*mp,
471 	struct xfs_efi_log_item	*efip,
472 	uint			nextents)
473 
474 {
475 	struct xfs_efd_log_item	*efdp;
476 	uint			size;
477 
478 	ASSERT(nextents > 0);
479 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
480 		size = (uint)(sizeof(xfs_efd_log_item_t) +
481 			((nextents - 1) * sizeof(xfs_extent_t)));
482 		efdp = kmem_zalloc(size, KM_SLEEP);
483 	} else {
484 		efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
485 	}
486 
487 	xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
488 	efdp->efd_efip = efip;
489 	efdp->efd_format.efd_nextents = nextents;
490 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
491 
492 	return efdp;
493 }
494