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37b3b4d6 | 1 | // SPDX-License-Identifier: GPL-2.0+ |
a18e1f79 DW |
2 | /* |
3 | * Copyright (C) 2016 Oracle. All Rights Reserved. | |
a18e1f79 | 4 | * Author: Darrick J. Wong <darrick.wong@oracle.com> |
a18e1f79 DW |
5 | */ |
6 | #include "libxfs_priv.h" | |
7 | #include "xfs_fs.h" | |
8 | #include "xfs_shared.h" | |
9 | #include "xfs_format.h" | |
10 | #include "xfs_log_format.h" | |
11 | #include "xfs_trans_resv.h" | |
12 | #include "xfs_bit.h" | |
13 | #include "xfs_sb.h" | |
14 | #include "xfs_mount.h" | |
15 | #include "xfs_defer.h" | |
16 | #include "xfs_trans.h" | |
17 | #include "xfs_trace.h" | |
18 | ||
19 | /* | |
20 | * Deferred Operations in XFS | |
21 | * | |
22 | * Due to the way locking rules work in XFS, certain transactions (block | |
23 | * mapping and unmapping, typically) have permanent reservations so that | |
24 | * we can roll the transaction to adhere to AG locking order rules and | |
25 | * to unlock buffers between metadata updates. Prior to rmap/reflink, | |
26 | * the mapping code had a mechanism to perform these deferrals for | |
27 | * extents that were going to be freed; this code makes that facility | |
28 | * more generic. | |
29 | * | |
30 | * When adding the reverse mapping and reflink features, it became | |
31 | * necessary to perform complex remapping multi-transactions to comply | |
32 | * with AG locking order rules, and to be able to spread a single | |
33 | * refcount update operation (an operation on an n-block extent can | |
34 | * update as many as n records!) among multiple transactions. XFS can | |
35 | * roll a transaction to facilitate this, but using this facility | |
36 | * requires us to log "intent" items in case log recovery needs to | |
37 | * redo the operation, and to log "done" items to indicate that redo | |
38 | * is not necessary. | |
39 | * | |
40 | * Deferred work is tracked in xfs_defer_pending items. Each pending | |
41 | * item tracks one type of deferred work. Incoming work items (which | |
42 | * have not yet had an intent logged) are attached to a pending item | |
43 | * on the dop_intake list, where they wait for the caller to finish | |
44 | * the deferred operations. | |
45 | * | |
46 | * Finishing a set of deferred operations is an involved process. To | |
47 | * start, we define "rolling a deferred-op transaction" as follows: | |
48 | * | |
49 | * > For each xfs_defer_pending item on the dop_intake list, | |
50 | * - Sort the work items in AG order. XFS locking | |
51 | * order rules require us to lock buffers in AG order. | |
52 | * - Create a log intent item for that type. | |
53 | * - Attach it to the pending item. | |
54 | * - Move the pending item from the dop_intake list to the | |
55 | * dop_pending list. | |
56 | * > Roll the transaction. | |
57 | * | |
58 | * NOTE: To avoid exceeding the transaction reservation, we limit the | |
59 | * number of items that we attach to a given xfs_defer_pending. | |
60 | * | |
61 | * The actual finishing process looks like this: | |
62 | * | |
63 | * > For each xfs_defer_pending in the dop_pending list, | |
64 | * - Roll the deferred-op transaction as above. | |
65 | * - Create a log done item for that type, and attach it to the | |
66 | * log intent item. | |
67 | * - For each work item attached to the log intent item, | |
68 | * * Perform the described action. | |
69 | * * Attach the work item to the log done item. | |
0590692e DW |
70 | * * If the result of doing the work was -EAGAIN, ->finish work |
71 | * wants a new transaction. See the "Requesting a Fresh | |
72 | * Transaction while Finishing Deferred Work" section below for | |
73 | * details. | |
a18e1f79 DW |
74 | * |
75 | * The key here is that we must log an intent item for all pending | |
76 | * work items every time we roll the transaction, and that we must log | |
77 | * a done item as soon as the work is completed. With this mechanism | |
78 | * we can perform complex remapping operations, chaining intent items | |
79 | * as needed. | |
80 | * | |
0590692e DW |
81 | * Requesting a Fresh Transaction while Finishing Deferred Work |
82 | * | |
83 | * If ->finish_item decides that it needs a fresh transaction to | |
84 | * finish the work, it must ask its caller (xfs_defer_finish) for a | |
85 | * continuation. The most likely cause of this circumstance are the | |
86 | * refcount adjust functions deciding that they've logged enough items | |
87 | * to be at risk of exceeding the transaction reservation. | |
88 | * | |
89 | * To get a fresh transaction, we want to log the existing log done | |
90 | * item to prevent the log intent item from replaying, immediately log | |
91 | * a new log intent item with the unfinished work items, roll the | |
92 | * transaction, and re-call ->finish_item wherever it left off. The | |
93 | * log done item and the new log intent item must be in the same | |
94 | * transaction or atomicity cannot be guaranteed; defer_finish ensures | |
95 | * that this happens. | |
96 | * | |
97 | * This requires some coordination between ->finish_item and | |
98 | * defer_finish. Upon deciding to request a new transaction, | |
99 | * ->finish_item should update the current work item to reflect the | |
100 | * unfinished work. Next, it should reset the log done item's list | |
101 | * count to the number of items finished, and return -EAGAIN. | |
102 | * defer_finish sees the -EAGAIN, logs the new log intent item | |
103 | * with the remaining work items, and leaves the xfs_defer_pending | |
104 | * item at the head of the dop_work queue. Then it rolls the | |
105 | * transaction and picks up processing where it left off. It is | |
106 | * required that ->finish_item must be careful to leave enough | |
107 | * transaction reservation to fit the new log intent item. | |
108 | * | |
a18e1f79 DW |
109 | * This is an example of remapping the extent (E, E+B) into file X at |
110 | * offset A and dealing with the extent (C, C+B) already being mapped | |
111 | * there: | |
112 | * +-------------------------------------------------+ | |
113 | * | Unmap file X startblock C offset A length B | t0 | |
114 | * | Intent to reduce refcount for extent (C, B) | | |
115 | * | Intent to remove rmap (X, C, A, B) | | |
116 | * | Intent to free extent (D, 1) (bmbt block) | | |
117 | * | Intent to map (X, A, B) at startblock E | | |
118 | * +-------------------------------------------------+ | |
119 | * | Map file X startblock E offset A length B | t1 | |
120 | * | Done mapping (X, E, A, B) | | |
121 | * | Intent to increase refcount for extent (E, B) | | |
122 | * | Intent to add rmap (X, E, A, B) | | |
123 | * +-------------------------------------------------+ | |
124 | * | Reduce refcount for extent (C, B) | t2 | |
0590692e DW |
125 | * | Done reducing refcount for extent (C, 9) | |
126 | * | Intent to reduce refcount for extent (C+9, B-9) | | |
127 | * | (ran out of space after 9 refcount updates) | | |
128 | * +-------------------------------------------------+ | |
129 | * | Reduce refcount for extent (C+9, B+9) | t3 | |
130 | * | Done reducing refcount for extent (C+9, B-9) | | |
a18e1f79 DW |
131 | * | Increase refcount for extent (E, B) | |
132 | * | Done increasing refcount for extent (E, B) | | |
133 | * | Intent to free extent (C, B) | | |
134 | * | Intent to free extent (F, 1) (refcountbt block) | | |
135 | * | Intent to remove rmap (F, 1, REFC) | | |
136 | * +-------------------------------------------------+ | |
0590692e | 137 | * | Remove rmap (X, C, A, B) | t4 |
a18e1f79 DW |
138 | * | Done removing rmap (X, C, A, B) | |
139 | * | Add rmap (X, E, A, B) | | |
140 | * | Done adding rmap (X, E, A, B) | | |
141 | * | Remove rmap (F, 1, REFC) | | |
142 | * | Done removing rmap (F, 1, REFC) | | |
143 | * +-------------------------------------------------+ | |
0590692e | 144 | * | Free extent (C, B) | t5 |
a18e1f79 DW |
145 | * | Done freeing extent (C, B) | |
146 | * | Free extent (D, 1) | | |
147 | * | Done freeing extent (D, 1) | | |
148 | * | Free extent (F, 1) | | |
149 | * | Done freeing extent (F, 1) | | |
150 | * +-------------------------------------------------+ | |
151 | * | |
152 | * If we should crash before t2 commits, log recovery replays | |
153 | * the following intent items: | |
154 | * | |
155 | * - Intent to reduce refcount for extent (C, B) | |
156 | * - Intent to remove rmap (X, C, A, B) | |
157 | * - Intent to free extent (D, 1) (bmbt block) | |
158 | * - Intent to increase refcount for extent (E, B) | |
159 | * - Intent to add rmap (X, E, A, B) | |
160 | * | |
161 | * In the process of recovering, it should also generate and take care | |
162 | * of these intent items: | |
163 | * | |
164 | * - Intent to free extent (C, B) | |
165 | * - Intent to free extent (F, 1) (refcountbt block) | |
166 | * - Intent to remove rmap (F, 1, REFC) | |
0590692e DW |
167 | * |
168 | * Note that the continuation requested between t2 and t3 is likely to | |
169 | * reoccur. | |
a18e1f79 DW |
170 | */ |
171 | ||
172 | static const struct xfs_defer_op_type *defer_op_types[XFS_DEFER_OPS_TYPE_MAX]; | |
173 | ||
174 | /* | |
175 | * For each pending item in the intake list, log its intent item and the | |
176 | * associated extents, then add the entire intake list to the end of | |
177 | * the pending list. | |
178 | */ | |
179 | STATIC void | |
180 | xfs_defer_intake_work( | |
181 | struct xfs_trans *tp, | |
182 | struct xfs_defer_ops *dop) | |
183 | { | |
184 | struct list_head *li; | |
185 | struct xfs_defer_pending *dfp; | |
186 | ||
187 | list_for_each_entry(dfp, &dop->dop_intake, dfp_list) { | |
188 | dfp->dfp_intent = dfp->dfp_type->create_intent(tp, | |
189 | dfp->dfp_count); | |
077dd509 | 190 | trace_xfs_defer_intake_work(tp->t_mountp, dfp); |
a18e1f79 DW |
191 | list_sort(tp->t_mountp, &dfp->dfp_work, |
192 | dfp->dfp_type->diff_items); | |
193 | list_for_each(li, &dfp->dfp_work) | |
194 | dfp->dfp_type->log_item(tp, dfp->dfp_intent, li); | |
195 | } | |
196 | ||
197 | list_splice_tail_init(&dop->dop_intake, &dop->dop_pending); | |
198 | } | |
199 | ||
200 | /* Abort all the intents that were committed. */ | |
201 | STATIC void | |
202 | xfs_defer_trans_abort( | |
203 | struct xfs_trans *tp, | |
204 | struct xfs_defer_ops *dop, | |
205 | int error) | |
206 | { | |
207 | struct xfs_defer_pending *dfp; | |
208 | ||
f11d5edd | 209 | trace_xfs_defer_trans_abort(tp->t_mountp, dop, _RET_IP_); |
a18e1f79 | 210 | |
077dd509 | 211 | /* Abort intent items that don't have a done item. */ |
a18e1f79 | 212 | list_for_each_entry(dfp, &dop->dop_pending, dfp_list) { |
30ad7d6e | 213 | trace_xfs_defer_pending_abort(tp->t_mountp, dfp); |
077dd509 | 214 | if (dfp->dfp_intent && !dfp->dfp_done) { |
a18e1f79 | 215 | dfp->dfp_type->abort_intent(dfp->dfp_intent); |
077dd509 DW |
216 | dfp->dfp_intent = NULL; |
217 | } | |
a18e1f79 DW |
218 | } |
219 | ||
220 | /* Shut down FS. */ | |
221 | xfs_force_shutdown(tp->t_mountp, (error == -EFSCORRUPTED) ? | |
222 | SHUTDOWN_CORRUPT_INCORE : SHUTDOWN_META_IO_ERROR); | |
223 | } | |
224 | ||
225 | /* Roll a transaction so we can do some deferred op processing. */ | |
226 | STATIC int | |
227 | xfs_defer_trans_roll( | |
228 | struct xfs_trans **tp, | |
d67406c9 | 229 | struct xfs_defer_ops *dop) |
a18e1f79 DW |
230 | { |
231 | int i; | |
232 | int error; | |
233 | ||
d67406c9 CH |
234 | /* Log all the joined inodes. */ |
235 | for (i = 0; i < XFS_DEFER_OPS_NR_INODES && dop->dop_inodes[i]; i++) | |
a18e1f79 | 236 | xfs_trans_log_inode(*tp, dop->dop_inodes[i], XFS_ILOG_CORE); |
a18e1f79 | 237 | |
6f67c32d DW |
238 | /* Hold the (previously bjoin'd) buffer locked across the roll. */ |
239 | for (i = 0; i < XFS_DEFER_OPS_NR_BUFS && dop->dop_bufs[i]; i++) | |
240 | xfs_trans_dirty_buf(*tp, dop->dop_bufs[i]); | |
241 | ||
f11d5edd | 242 | trace_xfs_defer_trans_roll((*tp)->t_mountp, dop, _RET_IP_); |
30ad7d6e | 243 | |
a18e1f79 | 244 | /* Roll the transaction. */ |
d67406c9 | 245 | error = xfs_trans_roll(tp); |
a18e1f79 | 246 | if (error) { |
30ad7d6e | 247 | trace_xfs_defer_trans_roll_error((*tp)->t_mountp, dop, error); |
a18e1f79 DW |
248 | xfs_defer_trans_abort(*tp, dop, error); |
249 | return error; | |
250 | } | |
251 | dop->dop_committed = true; | |
252 | ||
d67406c9 CH |
253 | /* Rejoin the joined inodes. */ |
254 | for (i = 0; i < XFS_DEFER_OPS_NR_INODES && dop->dop_inodes[i]; i++) | |
a18e1f79 | 255 | xfs_trans_ijoin(*tp, dop->dop_inodes[i], 0); |
a18e1f79 | 256 | |
6f67c32d DW |
257 | /* Rejoin the buffers and dirty them so the log moves forward. */ |
258 | for (i = 0; i < XFS_DEFER_OPS_NR_BUFS && dop->dop_bufs[i]; i++) { | |
259 | xfs_trans_bjoin(*tp, dop->dop_bufs[i]); | |
260 | xfs_trans_bhold(*tp, dop->dop_bufs[i]); | |
261 | } | |
262 | ||
a18e1f79 DW |
263 | return error; |
264 | } | |
265 | ||
266 | /* Do we have any work items to finish? */ | |
267 | bool | |
268 | xfs_defer_has_unfinished_work( | |
269 | struct xfs_defer_ops *dop) | |
270 | { | |
271 | return !list_empty(&dop->dop_pending) || !list_empty(&dop->dop_intake); | |
272 | } | |
273 | ||
274 | /* | |
275 | * Add this inode to the deferred op. Each joined inode is relogged | |
5c33baee | 276 | * each time we roll the transaction. |
a18e1f79 DW |
277 | */ |
278 | int | |
277d3c3a | 279 | xfs_defer_ijoin( |
a18e1f79 DW |
280 | struct xfs_defer_ops *dop, |
281 | struct xfs_inode *ip) | |
282 | { | |
283 | int i; | |
284 | ||
285 | for (i = 0; i < XFS_DEFER_OPS_NR_INODES; i++) { | |
286 | if (dop->dop_inodes[i] == ip) | |
287 | return 0; | |
288 | else if (dop->dop_inodes[i] == NULL) { | |
289 | dop->dop_inodes[i] = ip; | |
290 | return 0; | |
291 | } | |
292 | } | |
293 | ||
6f67c32d DW |
294 | ASSERT(0); |
295 | return -EFSCORRUPTED; | |
296 | } | |
297 | ||
298 | /* | |
299 | * Add this buffer to the deferred op. Each joined buffer is relogged | |
300 | * each time we roll the transaction. | |
301 | */ | |
302 | int | |
303 | xfs_defer_bjoin( | |
304 | struct xfs_defer_ops *dop, | |
305 | struct xfs_buf *bp) | |
306 | { | |
307 | int i; | |
308 | ||
309 | for (i = 0; i < XFS_DEFER_OPS_NR_BUFS; i++) { | |
310 | if (dop->dop_bufs[i] == bp) | |
311 | return 0; | |
312 | else if (dop->dop_bufs[i] == NULL) { | |
313 | dop->dop_bufs[i] = bp; | |
314 | return 0; | |
315 | } | |
316 | } | |
317 | ||
318 | ASSERT(0); | |
a18e1f79 DW |
319 | return -EFSCORRUPTED; |
320 | } | |
321 | ||
322 | /* | |
323 | * Finish all the pending work. This involves logging intent items for | |
324 | * any work items that wandered in since the last transaction roll (if | |
325 | * one has even happened), rolling the transaction, and finishing the | |
326 | * work items in the first item on the logged-and-pending list. | |
327 | * | |
328 | * If an inode is provided, relog it to the new transaction. | |
329 | */ | |
330 | int | |
331 | xfs_defer_finish( | |
332 | struct xfs_trans **tp, | |
5c33baee | 333 | struct xfs_defer_ops *dop) |
a18e1f79 DW |
334 | { |
335 | struct xfs_defer_pending *dfp; | |
336 | struct list_head *li; | |
337 | struct list_head *n; | |
a18e1f79 DW |
338 | void *state; |
339 | int error = 0; | |
340 | void (*cleanup_fn)(struct xfs_trans *, void *, int); | |
eb94763b | 341 | struct xfs_defer_ops *orig_dop; |
a18e1f79 DW |
342 | |
343 | ASSERT((*tp)->t_flags & XFS_TRANS_PERM_LOG_RES); | |
344 | ||
f11d5edd | 345 | trace_xfs_defer_finish((*tp)->t_mountp, dop, _RET_IP_); |
30ad7d6e | 346 | |
eb94763b BF |
347 | /* |
348 | * Attach dfops to the transaction during deferred ops processing. This | |
349 | * explicitly causes calls into the allocator to defer AGFL block frees. | |
350 | * Note that this code can go away once all dfops users attach to the | |
351 | * associated tp. | |
352 | */ | |
55fb19bb BF |
353 | ASSERT(!(*tp)->t_dfops || ((*tp)->t_dfops == dop)); |
354 | orig_dop = (*tp)->t_dfops; | |
355 | (*tp)->t_dfops = dop; | |
eb94763b | 356 | |
a18e1f79 DW |
357 | /* Until we run out of pending work to finish... */ |
358 | while (xfs_defer_has_unfinished_work(dop)) { | |
359 | /* Log intents for work items sitting in the intake. */ | |
360 | xfs_defer_intake_work(*tp, dop); | |
361 | ||
362 | /* Roll the transaction. */ | |
d67406c9 | 363 | error = xfs_defer_trans_roll(tp, dop); |
a18e1f79 DW |
364 | if (error) |
365 | goto out; | |
366 | ||
a18e1f79 DW |
367 | /* Log an intent-done item for the first pending item. */ |
368 | dfp = list_first_entry(&dop->dop_pending, | |
369 | struct xfs_defer_pending, dfp_list); | |
30ad7d6e | 370 | trace_xfs_defer_pending_finish((*tp)->t_mountp, dfp); |
11d87237 | 371 | dfp->dfp_done = dfp->dfp_type->create_done(*tp, dfp->dfp_intent, |
a18e1f79 DW |
372 | dfp->dfp_count); |
373 | cleanup_fn = dfp->dfp_type->finish_cleanup; | |
374 | ||
375 | /* Finish the work items. */ | |
376 | state = NULL; | |
377 | list_for_each_safe(li, n, &dfp->dfp_work) { | |
378 | list_del(li); | |
379 | dfp->dfp_count--; | |
380 | error = dfp->dfp_type->finish_item(*tp, dop, li, | |
11d87237 | 381 | dfp->dfp_done, &state); |
0590692e DW |
382 | if (error == -EAGAIN) { |
383 | /* | |
384 | * Caller wants a fresh transaction; | |
385 | * put the work item back on the list | |
386 | * and jump out. | |
387 | */ | |
388 | list_add(li, &dfp->dfp_work); | |
389 | dfp->dfp_count++; | |
390 | break; | |
391 | } else if (error) { | |
a18e1f79 DW |
392 | /* |
393 | * Clean up after ourselves and jump out. | |
394 | * xfs_defer_cancel will take care of freeing | |
395 | * all these lists and stuff. | |
396 | */ | |
397 | if (cleanup_fn) | |
398 | cleanup_fn(*tp, state, error); | |
399 | xfs_defer_trans_abort(*tp, dop, error); | |
400 | goto out; | |
401 | } | |
402 | } | |
0590692e DW |
403 | if (error == -EAGAIN) { |
404 | /* | |
405 | * Caller wants a fresh transaction, so log a | |
406 | * new log intent item to replace the old one | |
407 | * and roll the transaction. See "Requesting | |
408 | * a Fresh Transaction while Finishing | |
409 | * Deferred Work" above. | |
410 | */ | |
411 | dfp->dfp_intent = dfp->dfp_type->create_intent(*tp, | |
412 | dfp->dfp_count); | |
413 | dfp->dfp_done = NULL; | |
414 | list_for_each(li, &dfp->dfp_work) | |
415 | dfp->dfp_type->log_item(*tp, dfp->dfp_intent, | |
416 | li); | |
417 | } else { | |
418 | /* Done with the dfp, free it. */ | |
419 | list_del(&dfp->dfp_list); | |
420 | kmem_free(dfp); | |
421 | } | |
a18e1f79 DW |
422 | |
423 | if (cleanup_fn) | |
424 | cleanup_fn(*tp, state, error); | |
425 | } | |
426 | ||
04f6507c DW |
427 | /* |
428 | * Roll the transaction once more to avoid returning to the caller | |
429 | * with a dirty transaction. | |
430 | */ | |
431 | if ((*tp)->t_flags & XFS_TRANS_DIRTY) | |
432 | error = xfs_defer_trans_roll(tp, dop); | |
a18e1f79 | 433 | out: |
55fb19bb | 434 | (*tp)->t_dfops = orig_dop; |
30ad7d6e DW |
435 | if (error) |
436 | trace_xfs_defer_finish_error((*tp)->t_mountp, dop, error); | |
437 | else | |
f11d5edd | 438 | trace_xfs_defer_finish_done((*tp)->t_mountp, dop, _RET_IP_); |
a18e1f79 DW |
439 | return error; |
440 | } | |
441 | ||
442 | /* | |
443 | * Free up any items left in the list. | |
444 | */ | |
445 | void | |
446 | xfs_defer_cancel( | |
447 | struct xfs_defer_ops *dop) | |
448 | { | |
449 | struct xfs_defer_pending *dfp; | |
450 | struct xfs_defer_pending *pli; | |
451 | struct list_head *pwi; | |
452 | struct list_head *n; | |
453 | ||
f11d5edd | 454 | trace_xfs_defer_cancel(NULL, dop, _RET_IP_); |
30ad7d6e | 455 | |
a18e1f79 DW |
456 | /* |
457 | * Free the pending items. Caller should already have arranged | |
458 | * for the intent items to be released. | |
459 | */ | |
460 | list_for_each_entry_safe(dfp, pli, &dop->dop_intake, dfp_list) { | |
30ad7d6e | 461 | trace_xfs_defer_intake_cancel(NULL, dfp); |
a18e1f79 DW |
462 | list_del(&dfp->dfp_list); |
463 | list_for_each_safe(pwi, n, &dfp->dfp_work) { | |
464 | list_del(pwi); | |
465 | dfp->dfp_count--; | |
466 | dfp->dfp_type->cancel_item(pwi); | |
467 | } | |
468 | ASSERT(dfp->dfp_count == 0); | |
469 | kmem_free(dfp); | |
470 | } | |
471 | list_for_each_entry_safe(dfp, pli, &dop->dop_pending, dfp_list) { | |
30ad7d6e | 472 | trace_xfs_defer_pending_cancel(NULL, dfp); |
a18e1f79 DW |
473 | list_del(&dfp->dfp_list); |
474 | list_for_each_safe(pwi, n, &dfp->dfp_work) { | |
475 | list_del(pwi); | |
476 | dfp->dfp_count--; | |
477 | dfp->dfp_type->cancel_item(pwi); | |
478 | } | |
479 | ASSERT(dfp->dfp_count == 0); | |
480 | kmem_free(dfp); | |
481 | } | |
482 | } | |
483 | ||
484 | /* Add an item for later deferred processing. */ | |
485 | void | |
486 | xfs_defer_add( | |
487 | struct xfs_defer_ops *dop, | |
488 | enum xfs_defer_ops_type type, | |
489 | struct list_head *li) | |
490 | { | |
491 | struct xfs_defer_pending *dfp = NULL; | |
492 | ||
493 | /* | |
494 | * Add the item to a pending item at the end of the intake list. | |
495 | * If the last pending item has the same type, reuse it. Else, | |
496 | * create a new pending item at the end of the intake list. | |
497 | */ | |
498 | if (!list_empty(&dop->dop_intake)) { | |
499 | dfp = list_last_entry(&dop->dop_intake, | |
500 | struct xfs_defer_pending, dfp_list); | |
501 | if (dfp->dfp_type->type != type || | |
502 | (dfp->dfp_type->max_items && | |
503 | dfp->dfp_count >= dfp->dfp_type->max_items)) | |
504 | dfp = NULL; | |
505 | } | |
506 | if (!dfp) { | |
507 | dfp = kmem_alloc(sizeof(struct xfs_defer_pending), | |
508 | KM_SLEEP | KM_NOFS); | |
509 | dfp->dfp_type = defer_op_types[type]; | |
a18e1f79 | 510 | dfp->dfp_intent = NULL; |
11d87237 | 511 | dfp->dfp_done = NULL; |
a18e1f79 DW |
512 | dfp->dfp_count = 0; |
513 | INIT_LIST_HEAD(&dfp->dfp_work); | |
514 | list_add_tail(&dfp->dfp_list, &dop->dop_intake); | |
515 | } | |
516 | ||
517 | list_add_tail(li, &dfp->dfp_work); | |
518 | dfp->dfp_count++; | |
519 | } | |
520 | ||
521 | /* Initialize a deferred operation list. */ | |
522 | void | |
523 | xfs_defer_init_op_type( | |
524 | const struct xfs_defer_op_type *type) | |
525 | { | |
526 | defer_op_types[type->type] = type; | |
527 | } | |
528 | ||
529 | /* Initialize a deferred operation. */ | |
530 | void | |
531 | xfs_defer_init( | |
fe891182 | 532 | struct xfs_trans *tp, |
5cebfb23 | 533 | struct xfs_defer_ops *dop) |
a18e1f79 | 534 | { |
fe891182 BF |
535 | struct xfs_mount *mp = NULL; |
536 | ||
6f67c32d | 537 | memset(dop, 0, sizeof(struct xfs_defer_ops)); |
a18e1f79 DW |
538 | INIT_LIST_HEAD(&dop->dop_intake); |
539 | INIT_LIST_HEAD(&dop->dop_pending); | |
fe891182 | 540 | if (tp) { |
5cebfb23 | 541 | ASSERT(tp->t_firstblock == NULLFSBLOCK); |
fe891182 BF |
542 | tp->t_dfops = dop; |
543 | mp = tp->t_mountp; | |
544 | } | |
545 | trace_xfs_defer_init(mp, dop, _RET_IP_); | |
a18e1f79 | 546 | } |