xref: /openbmc/linux/fs/xfs/xfs_extfree_item.c (revision 2c684d89)
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_format.h"
21 #include "xfs_log_format.h"
22 #include "xfs_trans_resv.h"
23 #include "xfs_mount.h"
24 #include "xfs_trans.h"
25 #include "xfs_trans_priv.h"
26 #include "xfs_buf_item.h"
27 #include "xfs_extfree_item.h"
28 #include "xfs_log.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  * This returns the number of iovecs needed to log the given efi item.
51  * We only need 1 iovec for an efi item.  It just logs the efi_log_format
52  * structure.
53  */
54 static inline int
55 xfs_efi_item_sizeof(
56 	struct xfs_efi_log_item *efip)
57 {
58 	return sizeof(struct xfs_efi_log_format) +
59 	       (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
60 }
61 
62 STATIC void
63 xfs_efi_item_size(
64 	struct xfs_log_item	*lip,
65 	int			*nvecs,
66 	int			*nbytes)
67 {
68 	*nvecs += 1;
69 	*nbytes += xfs_efi_item_sizeof(EFI_ITEM(lip));
70 }
71 
72 /*
73  * This is called to fill in the vector of log iovecs for the
74  * given efi log item. We use only 1 iovec, and we point that
75  * at the efi_log_format structure embedded in the efi item.
76  * It is at this point that we assert that all of the extent
77  * slots in the efi item have been filled.
78  */
79 STATIC void
80 xfs_efi_item_format(
81 	struct xfs_log_item	*lip,
82 	struct xfs_log_vec	*lv)
83 {
84 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
85 	struct xfs_log_iovec	*vecp = NULL;
86 
87 	ASSERT(atomic_read(&efip->efi_next_extent) ==
88 				efip->efi_format.efi_nextents);
89 
90 	efip->efi_format.efi_type = XFS_LI_EFI;
91 	efip->efi_format.efi_size = 1;
92 
93 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_EFI_FORMAT,
94 			&efip->efi_format,
95 			xfs_efi_item_sizeof(efip));
96 }
97 
98 
99 /*
100  * Pinning has no meaning for an efi item, so just return.
101  */
102 STATIC void
103 xfs_efi_item_pin(
104 	struct xfs_log_item	*lip)
105 {
106 }
107 
108 /*
109  * The unpin operation is the last place an EFI is manipulated in the log. It is
110  * either inserted in the AIL or aborted in the event of a log I/O error. In
111  * either case, the EFI transaction has been successfully committed to make it
112  * this far. Therefore, we expect whoever committed the EFI to either construct
113  * and commit the EFD or drop the EFD's reference in the event of error. Simply
114  * drop the log's EFI reference now that the log is done with it.
115  */
116 STATIC void
117 xfs_efi_item_unpin(
118 	struct xfs_log_item	*lip,
119 	int			remove)
120 {
121 	struct xfs_efi_log_item	*efip = EFI_ITEM(lip);
122 	xfs_efi_release(efip);
123 }
124 
125 /*
126  * Efi items have no locking or pushing.  However, since EFIs are pulled from
127  * the AIL when their corresponding EFDs are committed to disk, their situation
128  * is very similar to being pinned.  Return XFS_ITEM_PINNED so that the caller
129  * will eventually flush the log.  This should help in getting the EFI out of
130  * the AIL.
131  */
132 STATIC uint
133 xfs_efi_item_push(
134 	struct xfs_log_item	*lip,
135 	struct list_head	*buffer_list)
136 {
137 	return XFS_ITEM_PINNED;
138 }
139 
140 /*
141  * The EFI has been either committed or aborted if the transaction has been
142  * cancelled. If the transaction was cancelled, an EFD isn't going to be
143  * constructed and thus we free the EFI here directly.
144  */
145 STATIC void
146 xfs_efi_item_unlock(
147 	struct xfs_log_item	*lip)
148 {
149 	if (lip->li_flags & XFS_LI_ABORTED)
150 		xfs_efi_item_free(EFI_ITEM(lip));
151 }
152 
153 /*
154  * The EFI is logged only once and cannot be moved in the log, so simply return
155  * the lsn at which it's been logged.
156  */
157 STATIC xfs_lsn_t
158 xfs_efi_item_committed(
159 	struct xfs_log_item	*lip,
160 	xfs_lsn_t		lsn)
161 {
162 	return lsn;
163 }
164 
165 /*
166  * The EFI dependency tracking op doesn't do squat.  It can't because
167  * it doesn't know where the free extent is coming from.  The dependency
168  * tracking has to be handled by the "enclosing" metadata object.  For
169  * example, for inodes, the inode is locked throughout the extent freeing
170  * so the dependency should be recorded there.
171  */
172 STATIC void
173 xfs_efi_item_committing(
174 	struct xfs_log_item	*lip,
175 	xfs_lsn_t		lsn)
176 {
177 }
178 
179 /*
180  * This is the ops vector shared by all efi log items.
181  */
182 static const struct xfs_item_ops xfs_efi_item_ops = {
183 	.iop_size	= xfs_efi_item_size,
184 	.iop_format	= xfs_efi_item_format,
185 	.iop_pin	= xfs_efi_item_pin,
186 	.iop_unpin	= xfs_efi_item_unpin,
187 	.iop_unlock	= xfs_efi_item_unlock,
188 	.iop_committed	= xfs_efi_item_committed,
189 	.iop_push	= xfs_efi_item_push,
190 	.iop_committing = xfs_efi_item_committing
191 };
192 
193 
194 /*
195  * Allocate and initialize an efi item with the given number of extents.
196  */
197 struct xfs_efi_log_item *
198 xfs_efi_init(
199 	struct xfs_mount	*mp,
200 	uint			nextents)
201 
202 {
203 	struct xfs_efi_log_item	*efip;
204 	uint			size;
205 
206 	ASSERT(nextents > 0);
207 	if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
208 		size = (uint)(sizeof(xfs_efi_log_item_t) +
209 			((nextents - 1) * sizeof(xfs_extent_t)));
210 		efip = kmem_zalloc(size, KM_SLEEP);
211 	} else {
212 		efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
213 	}
214 
215 	xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
216 	efip->efi_format.efi_nextents = nextents;
217 	efip->efi_format.efi_id = (uintptr_t)(void *)efip;
218 	atomic_set(&efip->efi_next_extent, 0);
219 	atomic_set(&efip->efi_refcount, 2);
220 
221 	return efip;
222 }
223 
224 /*
225  * Copy an EFI format buffer from the given buf, and into the destination
226  * EFI format structure.
227  * The given buffer can be in 32 bit or 64 bit form (which has different padding),
228  * one of which will be the native format for this kernel.
229  * It will handle the conversion of formats if necessary.
230  */
231 int
232 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
233 {
234 	xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
235 	uint i;
236 	uint len = sizeof(xfs_efi_log_format_t) +
237 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
238 	uint len32 = sizeof(xfs_efi_log_format_32_t) +
239 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
240 	uint len64 = sizeof(xfs_efi_log_format_64_t) +
241 		(src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
242 
243 	if (buf->i_len == len) {
244 		memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
245 		return 0;
246 	} else if (buf->i_len == len32) {
247 		xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
248 
249 		dst_efi_fmt->efi_type     = src_efi_fmt_32->efi_type;
250 		dst_efi_fmt->efi_size     = src_efi_fmt_32->efi_size;
251 		dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
252 		dst_efi_fmt->efi_id       = src_efi_fmt_32->efi_id;
253 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
254 			dst_efi_fmt->efi_extents[i].ext_start =
255 				src_efi_fmt_32->efi_extents[i].ext_start;
256 			dst_efi_fmt->efi_extents[i].ext_len =
257 				src_efi_fmt_32->efi_extents[i].ext_len;
258 		}
259 		return 0;
260 	} else if (buf->i_len == len64) {
261 		xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
262 
263 		dst_efi_fmt->efi_type     = src_efi_fmt_64->efi_type;
264 		dst_efi_fmt->efi_size     = src_efi_fmt_64->efi_size;
265 		dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
266 		dst_efi_fmt->efi_id       = src_efi_fmt_64->efi_id;
267 		for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
268 			dst_efi_fmt->efi_extents[i].ext_start =
269 				src_efi_fmt_64->efi_extents[i].ext_start;
270 			dst_efi_fmt->efi_extents[i].ext_len =
271 				src_efi_fmt_64->efi_extents[i].ext_len;
272 		}
273 		return 0;
274 	}
275 	return -EFSCORRUPTED;
276 }
277 
278 /*
279  * Freeing the efi requires that we remove it from the AIL if it has already
280  * been placed there. However, the EFI may not yet have been placed in the AIL
281  * when called by xfs_efi_release() from EFD processing due to the ordering of
282  * committed vs unpin operations in bulk insert operations. Hence the reference
283  * count to ensure only the last caller frees the EFI.
284  */
285 void
286 xfs_efi_release(
287 	struct xfs_efi_log_item	*efip)
288 {
289 	if (atomic_dec_and_test(&efip->efi_refcount)) {
290 		xfs_trans_ail_remove(&efip->efi_item, SHUTDOWN_LOG_IO_ERROR);
291 		xfs_efi_item_free(efip);
292 	}
293 }
294 
295 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
296 {
297 	return container_of(lip, struct xfs_efd_log_item, efd_item);
298 }
299 
300 STATIC void
301 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
302 {
303 	if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
304 		kmem_free(efdp);
305 	else
306 		kmem_zone_free(xfs_efd_zone, efdp);
307 }
308 
309 /*
310  * This returns the number of iovecs needed to log the given efd item.
311  * We only need 1 iovec for an efd item.  It just logs the efd_log_format
312  * structure.
313  */
314 static inline int
315 xfs_efd_item_sizeof(
316 	struct xfs_efd_log_item *efdp)
317 {
318 	return sizeof(xfs_efd_log_format_t) +
319 	       (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
320 }
321 
322 STATIC void
323 xfs_efd_item_size(
324 	struct xfs_log_item	*lip,
325 	int			*nvecs,
326 	int			*nbytes)
327 {
328 	*nvecs += 1;
329 	*nbytes += xfs_efd_item_sizeof(EFD_ITEM(lip));
330 }
331 
332 /*
333  * This is called to fill in the vector of log iovecs for the
334  * given efd log item. We use only 1 iovec, and we point that
335  * at the efd_log_format structure embedded in the efd item.
336  * It is at this point that we assert that all of the extent
337  * slots in the efd item have been filled.
338  */
339 STATIC void
340 xfs_efd_item_format(
341 	struct xfs_log_item	*lip,
342 	struct xfs_log_vec	*lv)
343 {
344 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
345 	struct xfs_log_iovec	*vecp = NULL;
346 
347 	ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
348 
349 	efdp->efd_format.efd_type = XFS_LI_EFD;
350 	efdp->efd_format.efd_size = 1;
351 
352 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_EFD_FORMAT,
353 			&efdp->efd_format,
354 			xfs_efd_item_sizeof(efdp));
355 }
356 
357 /*
358  * Pinning has no meaning for an efd item, so just return.
359  */
360 STATIC void
361 xfs_efd_item_pin(
362 	struct xfs_log_item	*lip)
363 {
364 }
365 
366 /*
367  * Since pinning has no meaning for an efd item, unpinning does
368  * not either.
369  */
370 STATIC void
371 xfs_efd_item_unpin(
372 	struct xfs_log_item	*lip,
373 	int			remove)
374 {
375 }
376 
377 /*
378  * There isn't much you can do to push on an efd item.  It is simply stuck
379  * waiting for the log to be flushed to disk.
380  */
381 STATIC uint
382 xfs_efd_item_push(
383 	struct xfs_log_item	*lip,
384 	struct list_head	*buffer_list)
385 {
386 	return XFS_ITEM_PINNED;
387 }
388 
389 /*
390  * The EFD is either committed or aborted if the transaction is cancelled. If
391  * the transaction is cancelled, drop our reference to the EFI and free the EFD.
392  */
393 STATIC void
394 xfs_efd_item_unlock(
395 	struct xfs_log_item	*lip)
396 {
397 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
398 
399 	if (lip->li_flags & XFS_LI_ABORTED) {
400 		xfs_efi_release(efdp->efd_efip);
401 		xfs_efd_item_free(efdp);
402 	}
403 }
404 
405 /*
406  * When the efd item is committed to disk, all we need to do is delete our
407  * reference to our partner efi item and then free ourselves. Since we're
408  * freeing ourselves we must return -1 to keep the transaction code from further
409  * referencing this item.
410  */
411 STATIC xfs_lsn_t
412 xfs_efd_item_committed(
413 	struct xfs_log_item	*lip,
414 	xfs_lsn_t		lsn)
415 {
416 	struct xfs_efd_log_item	*efdp = EFD_ITEM(lip);
417 
418 	/*
419 	 * Drop the EFI reference regardless of whether the EFD has been
420 	 * aborted. Once the EFD transaction is constructed, it is the sole
421 	 * responsibility of the EFD to release the EFI (even if the EFI is
422 	 * aborted due to log I/O error).
423 	 */
424 	xfs_efi_release(efdp->efd_efip);
425 	xfs_efd_item_free(efdp);
426 
427 	return (xfs_lsn_t)-1;
428 }
429 
430 /*
431  * The EFD dependency tracking op doesn't do squat.  It can't because
432  * it doesn't know where the free extent is coming from.  The dependency
433  * tracking has to be handled by the "enclosing" metadata object.  For
434  * example, for inodes, the inode is locked throughout the extent freeing
435  * so the dependency should be recorded there.
436  */
437 STATIC void
438 xfs_efd_item_committing(
439 	struct xfs_log_item	*lip,
440 	xfs_lsn_t		lsn)
441 {
442 }
443 
444 /*
445  * This is the ops vector shared by all efd log items.
446  */
447 static const struct xfs_item_ops xfs_efd_item_ops = {
448 	.iop_size	= xfs_efd_item_size,
449 	.iop_format	= xfs_efd_item_format,
450 	.iop_pin	= xfs_efd_item_pin,
451 	.iop_unpin	= xfs_efd_item_unpin,
452 	.iop_unlock	= xfs_efd_item_unlock,
453 	.iop_committed	= xfs_efd_item_committed,
454 	.iop_push	= xfs_efd_item_push,
455 	.iop_committing = xfs_efd_item_committing
456 };
457 
458 /*
459  * Allocate and initialize an efd item with the given number of extents.
460  */
461 struct xfs_efd_log_item *
462 xfs_efd_init(
463 	struct xfs_mount	*mp,
464 	struct xfs_efi_log_item	*efip,
465 	uint			nextents)
466 
467 {
468 	struct xfs_efd_log_item	*efdp;
469 	uint			size;
470 
471 	ASSERT(nextents > 0);
472 	if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
473 		size = (uint)(sizeof(xfs_efd_log_item_t) +
474 			((nextents - 1) * sizeof(xfs_extent_t)));
475 		efdp = kmem_zalloc(size, KM_SLEEP);
476 	} else {
477 		efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
478 	}
479 
480 	xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
481 	efdp->efd_efip = efip;
482 	efdp->efd_format.efd_nextents = nextents;
483 	efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
484 
485 	return efdp;
486 }
487