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1 /*
2 * Copyright (C) 2016 Oracle. All Rights Reserved.
3 *
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it would be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20 #include "xfs.h"
21 #include "xfs_fs.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_bit.h"
26 #include "xfs_mount.h"
27 #include "xfs_defer.h"
28 #include "xfs_trans.h"
29 #include "xfs_trans_priv.h"
30 #include "xfs_buf_item.h"
31 #include "xfs_rmap_item.h"
32 #include "xfs_log.h"
33 #include "xfs_rmap.h"
34
35
36 kmem_zone_t *xfs_rui_zone;
37 kmem_zone_t *xfs_rud_zone;
38
39 static inline struct xfs_rui_log_item *RUI_ITEM(struct xfs_log_item *lip)
40 {
41 return container_of(lip, struct xfs_rui_log_item, rui_item);
42 }
43
44 void
45 xfs_rui_item_free(
46 struct xfs_rui_log_item *ruip)
47 {
48 if (ruip->rui_format.rui_nextents > XFS_RUI_MAX_FAST_EXTENTS)
49 kmem_free(ruip);
50 else
51 kmem_zone_free(xfs_rui_zone, ruip);
52 }
53
54 STATIC void
55 xfs_rui_item_size(
56 struct xfs_log_item *lip,
57 int *nvecs,
58 int *nbytes)
59 {
60 struct xfs_rui_log_item *ruip = RUI_ITEM(lip);
61
62 *nvecs += 1;
63 *nbytes += xfs_rui_log_format_sizeof(ruip->rui_format.rui_nextents);
64 }
65
66 /*
67 * This is called to fill in the vector of log iovecs for the
68 * given rui log item. We use only 1 iovec, and we point that
69 * at the rui_log_format structure embedded in the rui item.
70 * It is at this point that we assert that all of the extent
71 * slots in the rui item have been filled.
72 */
73 STATIC void
74 xfs_rui_item_format(
75 struct xfs_log_item *lip,
76 struct xfs_log_vec *lv)
77 {
78 struct xfs_rui_log_item *ruip = RUI_ITEM(lip);
79 struct xfs_log_iovec *vecp = NULL;
80
81 ASSERT(atomic_read(&ruip->rui_next_extent) ==
82 ruip->rui_format.rui_nextents);
83
84 ruip->rui_format.rui_type = XFS_LI_RUI;
85 ruip->rui_format.rui_size = 1;
86
87 xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_RUI_FORMAT, &ruip->rui_format,
88 xfs_rui_log_format_sizeof(ruip->rui_format.rui_nextents));
89 }
90
91 /*
92 * Pinning has no meaning for an rui item, so just return.
93 */
94 STATIC void
95 xfs_rui_item_pin(
96 struct xfs_log_item *lip)
97 {
98 }
99
100 /*
101 * The unpin operation is the last place an RUI is manipulated in the log. It is
102 * either inserted in the AIL or aborted in the event of a log I/O error. In
103 * either case, the RUI transaction has been successfully committed to make it
104 * this far. Therefore, we expect whoever committed the RUI to either construct
105 * and commit the RUD or drop the RUD's reference in the event of error. Simply
106 * drop the log's RUI reference now that the log is done with it.
107 */
108 STATIC void
109 xfs_rui_item_unpin(
110 struct xfs_log_item *lip,
111 int remove)
112 {
113 struct xfs_rui_log_item *ruip = RUI_ITEM(lip);
114
115 xfs_rui_release(ruip);
116 }
117
118 /*
119 * RUI items have no locking or pushing. However, since RUIs are pulled from
120 * the AIL when their corresponding RUDs are committed to disk, their situation
121 * is very similar to being pinned. Return XFS_ITEM_PINNED so that the caller
122 * will eventually flush the log. This should help in getting the RUI out of
123 * the AIL.
124 */
125 STATIC uint
126 xfs_rui_item_push(
127 struct xfs_log_item *lip,
128 struct list_head *buffer_list)
129 {
130 return XFS_ITEM_PINNED;
131 }
132
133 /*
134 * The RUI has been either committed or aborted if the transaction has been
135 * cancelled. If the transaction was cancelled, an RUD isn't going to be
136 * constructed and thus we free the RUI here directly.
137 */
138 STATIC void
139 xfs_rui_item_unlock(
140 struct xfs_log_item *lip)
141 {
142 if (lip->li_flags & XFS_LI_ABORTED)
143 xfs_rui_item_free(RUI_ITEM(lip));
144 }
145
146 /*
147 * The RUI is logged only once and cannot be moved in the log, so simply return
148 * the lsn at which it's been logged.
149 */
150 STATIC xfs_lsn_t
151 xfs_rui_item_committed(
152 struct xfs_log_item *lip,
153 xfs_lsn_t lsn)
154 {
155 return lsn;
156 }
157
158 /*
159 * The RUI dependency tracking op doesn't do squat. It can't because
160 * it doesn't know where the free extent is coming from. The dependency
161 * tracking has to be handled by the "enclosing" metadata object. For
162 * example, for inodes, the inode is locked throughout the extent freeing
163 * so the dependency should be recorded there.
164 */
165 STATIC void
166 xfs_rui_item_committing(
167 struct xfs_log_item *lip,
168 xfs_lsn_t lsn)
169 {
170 }
171
172 /*
173 * This is the ops vector shared by all rui log items.
174 */
175 static const struct xfs_item_ops xfs_rui_item_ops = {
176 .iop_size = xfs_rui_item_size,
177 .iop_format = xfs_rui_item_format,
178 .iop_pin = xfs_rui_item_pin,
179 .iop_unpin = xfs_rui_item_unpin,
180 .iop_unlock = xfs_rui_item_unlock,
181 .iop_committed = xfs_rui_item_committed,
182 .iop_push = xfs_rui_item_push,
183 .iop_committing = xfs_rui_item_committing,
184 };
185
186 /*
187 * Allocate and initialize an rui item with the given number of extents.
188 */
189 struct xfs_rui_log_item *
190 xfs_rui_init(
191 struct xfs_mount *mp,
192 uint nextents)
193
194 {
195 struct xfs_rui_log_item *ruip;
196
197 ASSERT(nextents > 0);
198 if (nextents > XFS_RUI_MAX_FAST_EXTENTS)
199 ruip = kmem_zalloc(xfs_rui_log_item_sizeof(nextents), KM_SLEEP);
200 else
201 ruip = kmem_zone_zalloc(xfs_rui_zone, KM_SLEEP);
202
203 xfs_log_item_init(mp, &ruip->rui_item, XFS_LI_RUI, &xfs_rui_item_ops);
204 ruip->rui_format.rui_nextents = nextents;
205 ruip->rui_format.rui_id = (uintptr_t)(void *)ruip;
206 atomic_set(&ruip->rui_next_extent, 0);
207 atomic_set(&ruip->rui_refcount, 2);
208
209 return ruip;
210 }
211
212 /*
213 * Copy an RUI format buffer from the given buf, and into the destination
214 * RUI format structure. The RUI/RUD items were designed not to need any
215 * special alignment handling.
216 */
217 int
218 xfs_rui_copy_format(
219 struct xfs_log_iovec *buf,
220 struct xfs_rui_log_format *dst_rui_fmt)
221 {
222 struct xfs_rui_log_format *src_rui_fmt;
223 uint len;
224
225 src_rui_fmt = buf->i_addr;
226 len = xfs_rui_log_format_sizeof(src_rui_fmt->rui_nextents);
227
228 if (buf->i_len != len)
229 return -EFSCORRUPTED;
230
231 memcpy(dst_rui_fmt, src_rui_fmt, len);
232 return 0;
233 }
234
235 /*
236 * Freeing the RUI requires that we remove it from the AIL if it has already
237 * been placed there. However, the RUI may not yet have been placed in the AIL
238 * when called by xfs_rui_release() from RUD processing due to the ordering of
239 * committed vs unpin operations in bulk insert operations. Hence the reference
240 * count to ensure only the last caller frees the RUI.
241 */
242 void
243 xfs_rui_release(
244 struct xfs_rui_log_item *ruip)
245 {
246 ASSERT(atomic_read(&ruip->rui_refcount) > 0);
247 if (atomic_dec_and_test(&ruip->rui_refcount)) {
248 xfs_trans_ail_remove(&ruip->rui_item, SHUTDOWN_LOG_IO_ERROR);
249 xfs_rui_item_free(ruip);
250 }
251 }
252
253 static inline struct xfs_rud_log_item *RUD_ITEM(struct xfs_log_item *lip)
254 {
255 return container_of(lip, struct xfs_rud_log_item, rud_item);
256 }
257
258 STATIC void
259 xfs_rud_item_size(
260 struct xfs_log_item *lip,
261 int *nvecs,
262 int *nbytes)
263 {
264 *nvecs += 1;
265 *nbytes += sizeof(struct xfs_rud_log_format);
266 }
267
268 /*
269 * This is called to fill in the vector of log iovecs for the
270 * given rud log item. We use only 1 iovec, and we point that
271 * at the rud_log_format structure embedded in the rud item.
272 * It is at this point that we assert that all of the extent
273 * slots in the rud item have been filled.
274 */
275 STATIC void
276 xfs_rud_item_format(
277 struct xfs_log_item *lip,
278 struct xfs_log_vec *lv)
279 {
280 struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
281 struct xfs_log_iovec *vecp = NULL;
282
283 rudp->rud_format.rud_type = XFS_LI_RUD;
284 rudp->rud_format.rud_size = 1;
285
286 xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_RUD_FORMAT, &rudp->rud_format,
287 sizeof(struct xfs_rud_log_format));
288 }
289
290 /*
291 * Pinning has no meaning for an rud item, so just return.
292 */
293 STATIC void
294 xfs_rud_item_pin(
295 struct xfs_log_item *lip)
296 {
297 }
298
299 /*
300 * Since pinning has no meaning for an rud item, unpinning does
301 * not either.
302 */
303 STATIC void
304 xfs_rud_item_unpin(
305 struct xfs_log_item *lip,
306 int remove)
307 {
308 }
309
310 /*
311 * There isn't much you can do to push on an rud item. It is simply stuck
312 * waiting for the log to be flushed to disk.
313 */
314 STATIC uint
315 xfs_rud_item_push(
316 struct xfs_log_item *lip,
317 struct list_head *buffer_list)
318 {
319 return XFS_ITEM_PINNED;
320 }
321
322 /*
323 * The RUD is either committed or aborted if the transaction is cancelled. If
324 * the transaction is cancelled, drop our reference to the RUI and free the
325 * RUD.
326 */
327 STATIC void
328 xfs_rud_item_unlock(
329 struct xfs_log_item *lip)
330 {
331 struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
332
333 if (lip->li_flags & XFS_LI_ABORTED) {
334 xfs_rui_release(rudp->rud_ruip);
335 kmem_zone_free(xfs_rud_zone, rudp);
336 }
337 }
338
339 /*
340 * When the rud item is committed to disk, all we need to do is delete our
341 * reference to our partner rui item and then free ourselves. Since we're
342 * freeing ourselves we must return -1 to keep the transaction code from
343 * further referencing this item.
344 */
345 STATIC xfs_lsn_t
346 xfs_rud_item_committed(
347 struct xfs_log_item *lip,
348 xfs_lsn_t lsn)
349 {
350 struct xfs_rud_log_item *rudp = RUD_ITEM(lip);
351
352 /*
353 * Drop the RUI reference regardless of whether the RUD has been
354 * aborted. Once the RUD transaction is constructed, it is the sole
355 * responsibility of the RUD to release the RUI (even if the RUI is
356 * aborted due to log I/O error).
357 */
358 xfs_rui_release(rudp->rud_ruip);
359 kmem_zone_free(xfs_rud_zone, rudp);
360
361 return (xfs_lsn_t)-1;
362 }
363
364 /*
365 * The RUD dependency tracking op doesn't do squat. It can't because
366 * it doesn't know where the free extent is coming from. The dependency
367 * tracking has to be handled by the "enclosing" metadata object. For
368 * example, for inodes, the inode is locked throughout the extent freeing
369 * so the dependency should be recorded there.
370 */
371 STATIC void
372 xfs_rud_item_committing(
373 struct xfs_log_item *lip,
374 xfs_lsn_t lsn)
375 {
376 }
377
378 /*
379 * This is the ops vector shared by all rud log items.
380 */
381 static const struct xfs_item_ops xfs_rud_item_ops = {
382 .iop_size = xfs_rud_item_size,
383 .iop_format = xfs_rud_item_format,
384 .iop_pin = xfs_rud_item_pin,
385 .iop_unpin = xfs_rud_item_unpin,
386 .iop_unlock = xfs_rud_item_unlock,
387 .iop_committed = xfs_rud_item_committed,
388 .iop_push = xfs_rud_item_push,
389 .iop_committing = xfs_rud_item_committing,
390 };
391
392 /*
393 * Allocate and initialize an rud item with the given number of extents.
394 */
395 struct xfs_rud_log_item *
396 xfs_rud_init(
397 struct xfs_mount *mp,
398 struct xfs_rui_log_item *ruip)
399
400 {
401 struct xfs_rud_log_item *rudp;
402
403 rudp = kmem_zone_zalloc(xfs_rud_zone, KM_SLEEP);
404 xfs_log_item_init(mp, &rudp->rud_item, XFS_LI_RUD, &xfs_rud_item_ops);
405 rudp->rud_ruip = ruip;
406 rudp->rud_format.rud_rui_id = ruip->rui_format.rui_id;
407
408 return rudp;
409 }
410
411 /*
412 * Process an rmap update intent item that was recovered from the log.
413 * We need to update the rmapbt.
414 */
415 int
416 xfs_rui_recover(
417 struct xfs_mount *mp,
418 struct xfs_rui_log_item *ruip)
419 {
420 int i;
421 int error = 0;
422 struct xfs_map_extent *rmap;
423 xfs_fsblock_t startblock_fsb;
424 bool op_ok;
425 struct xfs_rud_log_item *rudp;
426 enum xfs_rmap_intent_type type;
427 int whichfork;
428 xfs_exntst_t state;
429 struct xfs_trans *tp;
430 struct xfs_btree_cur *rcur = NULL;
431
432 ASSERT(!test_bit(XFS_RUI_RECOVERED, &ruip->rui_flags));
433
434 /*
435 * First check the validity of the extents described by the
436 * RUI. If any are bad, then assume that all are bad and
437 * just toss the RUI.
438 */
439 for (i = 0; i < ruip->rui_format.rui_nextents; i++) {
440 rmap = &ruip->rui_format.rui_extents[i];
441 startblock_fsb = XFS_BB_TO_FSB(mp,
442 XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
443 switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
444 case XFS_RMAP_EXTENT_MAP:
445 case XFS_RMAP_EXTENT_MAP_SHARED:
446 case XFS_RMAP_EXTENT_UNMAP:
447 case XFS_RMAP_EXTENT_UNMAP_SHARED:
448 case XFS_RMAP_EXTENT_CONVERT:
449 case XFS_RMAP_EXTENT_CONVERT_SHARED:
450 case XFS_RMAP_EXTENT_ALLOC:
451 case XFS_RMAP_EXTENT_FREE:
452 op_ok = true;
453 break;
454 default:
455 op_ok = false;
456 break;
457 }
458 if (!op_ok || startblock_fsb == 0 ||
459 rmap->me_len == 0 ||
460 startblock_fsb >= mp->m_sb.sb_dblocks ||
461 rmap->me_len >= mp->m_sb.sb_agblocks ||
462 (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS)) {
463 /*
464 * This will pull the RUI from the AIL and
465 * free the memory associated with it.
466 */
467 set_bit(XFS_RUI_RECOVERED, &ruip->rui_flags);
468 xfs_rui_release(ruip);
469 return -EIO;
470 }
471 }
472
473 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
474 if (error)
475 return error;
476 rudp = xfs_trans_get_rud(tp, ruip);
477
478 for (i = 0; i < ruip->rui_format.rui_nextents; i++) {
479 rmap = &ruip->rui_format.rui_extents[i];
480 state = (rmap->me_flags & XFS_RMAP_EXTENT_UNWRITTEN) ?
481 XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
482 whichfork = (rmap->me_flags & XFS_RMAP_EXTENT_ATTR_FORK) ?
483 XFS_ATTR_FORK : XFS_DATA_FORK;
484 switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
485 case XFS_RMAP_EXTENT_MAP:
486 type = XFS_RMAP_MAP;
487 break;
488 case XFS_RMAP_EXTENT_MAP_SHARED:
489 type = XFS_RMAP_MAP_SHARED;
490 break;
491 case XFS_RMAP_EXTENT_UNMAP:
492 type = XFS_RMAP_UNMAP;
493 break;
494 case XFS_RMAP_EXTENT_UNMAP_SHARED:
495 type = XFS_RMAP_UNMAP_SHARED;
496 break;
497 case XFS_RMAP_EXTENT_CONVERT:
498 type = XFS_RMAP_CONVERT;
499 break;
500 case XFS_RMAP_EXTENT_CONVERT_SHARED:
501 type = XFS_RMAP_CONVERT_SHARED;
502 break;
503 case XFS_RMAP_EXTENT_ALLOC:
504 type = XFS_RMAP_ALLOC;
505 break;
506 case XFS_RMAP_EXTENT_FREE:
507 type = XFS_RMAP_FREE;
508 break;
509 default:
510 error = -EFSCORRUPTED;
511 goto abort_error;
512 }
513 error = xfs_trans_log_finish_rmap_update(tp, rudp, type,
514 rmap->me_owner, whichfork,
515 rmap->me_startoff, rmap->me_startblock,
516 rmap->me_len, state, &rcur);
517 if (error)
518 goto abort_error;
519
520 }
521
522 xfs_rmap_finish_one_cleanup(tp, rcur, error);
523 set_bit(XFS_RUI_RECOVERED, &ruip->rui_flags);
524 error = xfs_trans_commit(tp);
525 return error;
526
527 abort_error:
528 xfs_rmap_finish_one_cleanup(tp, rcur, error);
529 xfs_trans_cancel(tp);
530 return error;
531 }