xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision f35e839a)
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 reference
54  * count to ensure only the last caller frees the EFI.
55  */
56 STATIC void
57 __xfs_efi_release(
58 	struct xfs_efi_log_item	*efip)
59 {
60 	struct xfs_ail		*ailp = efip->efi_item.li_ailp;
61 
62 	if (atomic_dec_and_test(&efip->efi_refcount)) {
63 		spin_lock(&ailp->xa_lock);
64 		/* xfs_trans_ail_delete() drops the AIL lock. */
65 		xfs_trans_ail_delete(ailp, &efip->efi_item,
66 				     SHUTDOWN_LOG_IO_ERROR);
67 		xfs_efi_item_free(efip);
68 	}
69 }
70 
71 /*
72  * This returns the number of iovecs needed to log the given efi item.
73  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
74  * structure.
75  */
76 STATIC uint
77 xfs_efi_item_size(
78 	struct xfs_log_item	*lip)
79 {
80 	return 1;
81 }
82 
83 /*
84  * This is called to fill in the vector of log iovecs for the
85  * given efi log item. We use only 1 iovec, and we point that
86  * at the efi_log_format structure embedded in the efi item.
87  * It is at this point that we assert that all of the extent
88  * slots in the efi item have been filled.
89  */
90 STATIC void
91 xfs_efi_item_format(
92 	struct xfs_log_item	*lip,
93 	struct xfs_log_iovec	*log_vector)
94 {
95 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
96 	uint			size;
97 
98 	ASSERT(atomic_read(&efip->efi_next_extent) ==
99 				efip->efi_format.efi_nextents);
100 
101 	efip->efi_format.efi_type = XFS_LI_EFI;
102 
103 	size = sizeof(xfs_efi_log_format_t);
104 	size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
105 	efip->efi_format.efi_size = 1;
106 
107 	log_vector->i_addr = &efip->efi_format;
108 	log_vector->i_len = size;
109 	log_vector->i_type = XLOG_REG_TYPE_EFI_FORMAT;
110 	ASSERT(size >= sizeof(xfs_efi_log_format_t));
111 }
112 
113 
114 /*
115  * Pinning has no meaning for an efi item, so just return.
116  */
117 STATIC void
118 xfs_efi_item_pin(
119 	struct xfs_log_item	*lip)
120 {
121 }
122 
123 /*
124  * While EFIs cannot really be pinned, the unpin operation is the last place at
125  * which the EFI is manipulated during a transaction.  If we are being asked to
126  * remove the EFI it's because the transaction has been cancelled and by
127  * definition that means the EFI cannot be in the AIL so remove it from the
128  * transaction and free it.  Otherwise coordinate with xfs_efi_release()
129  * to determine who gets to free the EFI.
130  */
131 STATIC void
132 xfs_efi_item_unpin(
133 	struct xfs_log_item	*lip,
134 	int			remove)
135 {
136 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
137 
138 	if (remove) {
139 		ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
140 		if (lip->li_desc)
141 			xfs_trans_del_item(lip);
142 		xfs_efi_item_free(efip);
143 		return;
144 	}
145 	__xfs_efi_release(efip);
146 }
147 
148 /*
149  * Efi items have no locking or pushing.  However, since EFIs are pulled from
150  * the AIL when their corresponding EFDs are committed to disk, their situation
151  * is very similar to being pinned.  Return XFS_ITEM_PINNED so that the caller
152  * will eventually flush the log.  This should help in getting the EFI out of
153  * the AIL.
154  */
155 STATIC uint
156 xfs_efi_item_push(
157 	struct xfs_log_item	*lip,
158 	struct list_head	*buffer_list)
159 {
160 	return XFS_ITEM_PINNED;
161 }
162 
163 STATIC void
164 xfs_efi_item_unlock(
165 	struct xfs_log_item	*lip)
166 {
167 	if (lip->li_flags & XFS_LI_ABORTED)
168 		xfs_efi_item_free(EFI_ITEM(lip));
169 }
170 
171 /*
172  * The EFI is logged only once and cannot be moved in the log, so simply return
173  * the lsn at which it's been logged.
174  */
175 STATIC xfs_lsn_t
176 xfs_efi_item_committed(
177 	struct xfs_log_item	*lip,
178 	xfs_lsn_t		lsn)
179 {
180 	return lsn;
181 }
182 
183 /*
184  * The EFI dependency tracking op doesn't do squat.  It can't because
185  * it doesn't know where the free extent is coming from.  The dependency
186  * tracking has to be handled by the "enclosing" metadata object.  For
187  * example, for inodes, the inode is locked throughout the extent freeing
188  * so the dependency should be recorded there.
189  */
190 STATIC void
191 xfs_efi_item_committing(
192 	struct xfs_log_item	*lip,
193 	xfs_lsn_t		lsn)
194 {
195 }
196 
197 /*
198  * This is the ops vector shared by all efi log items.
199  */
200 static const struct xfs_item_ops xfs_efi_item_ops = {
201 	.iop_size	= xfs_efi_item_size,
202 	.iop_format	= xfs_efi_item_format,
203 	.iop_pin	= xfs_efi_item_pin,
204 	.iop_unpin	= xfs_efi_item_unpin,
205 	.iop_unlock	= xfs_efi_item_unlock,
206 	.iop_committed	= xfs_efi_item_committed,
207 	.iop_push	= xfs_efi_item_push,
208 	.iop_committing = xfs_efi_item_committing
209 };
210 
211 
212 /*
213  * Allocate and initialize an efi item with the given number of extents.
214  */
215 struct xfs_efi_log_item *
216 xfs_efi_init(
217 	struct xfs_mount	*mp,
218 	uint			nextents)
219 
220 {
221 	struct xfs_efi_log_item	*efip;
222 	uint			size;
223 
224 	ASSERT(nextents > 0);
225 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
226 		size = (uint)(sizeof(xfs_efi_log_item_t) +
227 			((nextents - 1) * sizeof(xfs_extent_t)));
228 		efip = kmem_zalloc(size, KM_SLEEP);
229 	} else {
230 		efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
231 	}
232 
233 	xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
234 	efip->efi_format.efi_nextents = nextents;
235 	efip->efi_format.efi_id = (__psint_t)(void*)efip;
236 	atomic_set(&efip->efi_next_extent, 0);
237 	atomic_set(&efip->efi_refcount, 2);
238 
239 	return efip;
240 }
241 
242 /*
243  * Copy an EFI format buffer from the given buf, and into the destination
244  * EFI format structure.
245  * The given buffer can be in 32 bit or 64 bit form (which has different padding),
246  * one of which will be the native format for this kernel.
247  * It will handle the conversion of formats if necessary.
248  */
249 int
250 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
251 {
252 	xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
253 	uint i;
254 	uint len = sizeof(xfs_efi_log_format_t) +
255 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
256 	uint len32 = sizeof(xfs_efi_log_format_32_t) +
257 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
258 	uint len64 = sizeof(xfs_efi_log_format_64_t) +
259 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
260 
261 	if (buf->i_len == len) {
262 		memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
263 		return 0;
264 	} else if (buf->i_len == len32) {
265 		xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
266 
267 		dst_efi_fmt->efi_type     = src_efi_fmt_32->efi_type;
268 		dst_efi_fmt->efi_size     = src_efi_fmt_32->efi_size;
269 		dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
270 		dst_efi_fmt->efi_id       = src_efi_fmt_32->efi_id;
271 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
272 			dst_efi_fmt->efi_extents[i].ext_start =
273 				src_efi_fmt_32->efi_extents[i].ext_start;
274 			dst_efi_fmt->efi_extents[i].ext_len =
275 				src_efi_fmt_32->efi_extents[i].ext_len;
276 		}
277 		return 0;
278 	} else if (buf->i_len == len64) {
279 		xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
280 
281 		dst_efi_fmt->efi_type     = src_efi_fmt_64->efi_type;
282 		dst_efi_fmt->efi_size     = src_efi_fmt_64->efi_size;
283 		dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
284 		dst_efi_fmt->efi_id       = src_efi_fmt_64->efi_id;
285 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
286 			dst_efi_fmt->efi_extents[i].ext_start =
287 				src_efi_fmt_64->efi_extents[i].ext_start;
288 			dst_efi_fmt->efi_extents[i].ext_len =
289 				src_efi_fmt_64->efi_extents[i].ext_len;
290 		}
291 		return 0;
292 	}
293 	return EFSCORRUPTED;
294 }
295 
296 /*
297  * This is called by the efd item code below to release references to the given
298  * efi item.  Each efd calls this with the number of extents that it has
299  * logged, and when the sum of these reaches the total number of extents logged
300  * by this efi item we can free the efi item.
301  */
302 void
303 xfs_efi_release(xfs_efi_log_item_t	*efip,
304 		uint			nextents)
305 {
306 	ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
307 	if (atomic_sub_and_test(nextents, &efip->efi_next_extent)) {
308 		__xfs_efi_release(efip);
309 
310 		/* recovery needs us to drop the EFI reference, too */
311 		if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
312 			__xfs_efi_release(efip);
313 	}
314 }
315 
316 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
317 {
318 	return container_of(lip, struct xfs_efd_log_item, efd_item);
319 }
320 
321 STATIC void
322 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
323 {
324 	if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
325 		kmem_free(efdp);
326 	else
327 		kmem_zone_free(xfs_efd_zone, efdp);
328 }
329 
330 /*
331  * This returns the number of iovecs needed to log the given efd item.
332  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
333  * structure.
334  */
335 STATIC uint
336 xfs_efd_item_size(
337 	struct xfs_log_item	*lip)
338 {
339 	return 1;
340 }
341 
342 /*
343  * This is called to fill in the vector of log iovecs for the
344  * given efd log item. We use only 1 iovec, and we point that
345  * at the efd_log_format structure embedded in the efd item.
346  * It is at this point that we assert that all of the extent
347  * slots in the efd item have been filled.
348  */
349 STATIC void
350 xfs_efd_item_format(
351 	struct xfs_log_item	*lip,
352 	struct xfs_log_iovec	*log_vector)
353 {
354 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
355 	uint			size;
356 
357 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
358 
359 	efdp->efd_format.efd_type = XFS_LI_EFD;
360 
361 	size = sizeof(xfs_efd_log_format_t);
362 	size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
363 	efdp->efd_format.efd_size = 1;
364 
365 	log_vector->i_addr = &efdp->efd_format;
366 	log_vector->i_len = size;
367 	log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
368 	ASSERT(size >= sizeof(xfs_efd_log_format_t));
369 }
370 
371 /*
372  * Pinning has no meaning for an efd item, so just return.
373  */
374 STATIC void
375 xfs_efd_item_pin(
376 	struct xfs_log_item	*lip)
377 {
378 }
379 
380 /*
381  * Since pinning has no meaning for an efd item, unpinning does
382  * not either.
383  */
384 STATIC void
385 xfs_efd_item_unpin(
386 	struct xfs_log_item	*lip,
387 	int			remove)
388 {
389 }
390 
391 /*
392  * There isn't much you can do to push on an efd item.  It is simply stuck
393  * waiting for the log to be flushed to disk.
394  */
395 STATIC uint
396 xfs_efd_item_push(
397 	struct xfs_log_item	*lip,
398 	struct list_head	*buffer_list)
399 {
400 	return XFS_ITEM_PINNED;
401 }
402 
403 STATIC void
404 xfs_efd_item_unlock(
405 	struct xfs_log_item	*lip)
406 {
407 	if (lip->li_flags & XFS_LI_ABORTED)
408 		xfs_efd_item_free(EFD_ITEM(lip));
409 }
410 
411 /*
412  * When the efd item is committed to disk, all we need to do
413  * is delete our reference to our partner efi item and then
414  * free ourselves.  Since we're freeing ourselves we must
415  * return -1 to keep the transaction code from further referencing
416  * this item.
417  */
418 STATIC xfs_lsn_t
419 xfs_efd_item_committed(
420 	struct xfs_log_item	*lip,
421 	xfs_lsn_t		lsn)
422 {
423 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
424 
425 	/*
426 	 * If we got a log I/O error, it's always the case that the LR with the
427 	 * EFI got unpinned and freed before the EFD got aborted.
428 	 */
429 	if (!(lip->li_flags & XFS_LI_ABORTED))
430 		xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
431 
432 	xfs_efd_item_free(efdp);
433 	return (xfs_lsn_t)-1;
434 }
435 
436 /*
437  * The EFD dependency tracking op doesn't do squat.  It can't because
438  * it doesn't know where the free extent is coming from.  The dependency
439  * tracking has to be handled by the "enclosing" metadata object.  For
440  * example, for inodes, the inode is locked throughout the extent freeing
441  * so the dependency should be recorded there.
442  */
443 STATIC void
444 xfs_efd_item_committing(
445 	struct xfs_log_item	*lip,
446 	xfs_lsn_t		lsn)
447 {
448 }
449 
450 /*
451  * This is the ops vector shared by all efd log items.
452  */
453 static const struct xfs_item_ops xfs_efd_item_ops = {
454 	.iop_size	= xfs_efd_item_size,
455 	.iop_format	= xfs_efd_item_format,
456 	.iop_pin	= xfs_efd_item_pin,
457 	.iop_unpin	= xfs_efd_item_unpin,
458 	.iop_unlock	= xfs_efd_item_unlock,
459 	.iop_committed	= xfs_efd_item_committed,
460 	.iop_push	= xfs_efd_item_push,
461 	.iop_committing = xfs_efd_item_committing
462 };
463 
464 /*
465  * Allocate and initialize an efd item with the given number of extents.
466  */
467 struct xfs_efd_log_item *
468 xfs_efd_init(
469 	struct xfs_mount	*mp,
470 	struct xfs_efi_log_item	*efip,
471 	uint			nextents)
472 
473 {
474 	struct xfs_efd_log_item	*efdp;
475 	uint			size;
476 
477 	ASSERT(nextents > 0);
478 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
479 		size = (uint)(sizeof(xfs_efd_log_item_t) +
480 			((nextents - 1) * sizeof(xfs_extent_t)));
481 		efdp = kmem_zalloc(size, KM_SLEEP);
482 	} else {
483 		efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
484 	}
485 
486 	xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
487 	efdp->efd_efip = efip;
488 	efdp->efd_format.efd_nextents = nextents;
489 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
490 
491 	return efdp;
492 }
493