Commit | Line | Data |
---|---|---|
fe4fa4b8 DC |
1 | /* |
2 | * Copyright (c) 2000-2005 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" | |
fe4fa4b8 DC |
21 | #include "xfs_log.h" |
22 | #include "xfs_inum.h" | |
23 | #include "xfs_trans.h" | |
fd074841 | 24 | #include "xfs_trans_priv.h" |
fe4fa4b8 DC |
25 | #include "xfs_sb.h" |
26 | #include "xfs_ag.h" | |
fe4fa4b8 DC |
27 | #include "xfs_mount.h" |
28 | #include "xfs_bmap_btree.h" | |
fe4fa4b8 DC |
29 | #include "xfs_inode.h" |
30 | #include "xfs_dinode.h" | |
31 | #include "xfs_error.h" | |
fe4fa4b8 DC |
32 | #include "xfs_filestream.h" |
33 | #include "xfs_vnodeops.h" | |
fe4fa4b8 | 34 | #include "xfs_inode_item.h" |
7d095257 | 35 | #include "xfs_quota.h" |
0b1b213f | 36 | #include "xfs_trace.h" |
1a387d3b | 37 | #include "xfs_fsops.h" |
fe4fa4b8 | 38 | |
a167b17e DC |
39 | #include <linux/kthread.h> |
40 | #include <linux/freezer.h> | |
41 | ||
c6d09b66 DC |
42 | struct workqueue_struct *xfs_syncd_wq; /* sync workqueue */ |
43 | ||
78ae5256 DC |
44 | /* |
45 | * The inode lookup is done in batches to keep the amount of lock traffic and | |
46 | * radix tree lookups to a minimum. The batch size is a trade off between | |
47 | * lookup reduction and stack usage. This is in the reclaim path, so we can't | |
48 | * be too greedy. | |
49 | */ | |
50 | #define XFS_LOOKUP_BATCH 32 | |
51 | ||
e13de955 DC |
52 | STATIC int |
53 | xfs_inode_ag_walk_grab( | |
54 | struct xfs_inode *ip) | |
55 | { | |
56 | struct inode *inode = VFS_I(ip); | |
57 | ||
1a3e8f3d DC |
58 | ASSERT(rcu_read_lock_held()); |
59 | ||
60 | /* | |
61 | * check for stale RCU freed inode | |
62 | * | |
63 | * If the inode has been reallocated, it doesn't matter if it's not in | |
64 | * the AG we are walking - we are walking for writeback, so if it | |
65 | * passes all the "valid inode" checks and is dirty, then we'll write | |
66 | * it back anyway. If it has been reallocated and still being | |
67 | * initialised, the XFS_INEW check below will catch it. | |
68 | */ | |
69 | spin_lock(&ip->i_flags_lock); | |
70 | if (!ip->i_ino) | |
71 | goto out_unlock_noent; | |
72 | ||
73 | /* avoid new or reclaimable inodes. Leave for reclaim code to flush */ | |
74 | if (__xfs_iflags_test(ip, XFS_INEW | XFS_IRECLAIMABLE | XFS_IRECLAIM)) | |
75 | goto out_unlock_noent; | |
76 | spin_unlock(&ip->i_flags_lock); | |
77 | ||
e13de955 DC |
78 | /* nothing to sync during shutdown */ |
79 | if (XFS_FORCED_SHUTDOWN(ip->i_mount)) | |
80 | return EFSCORRUPTED; | |
81 | ||
e13de955 DC |
82 | /* If we can't grab the inode, it must on it's way to reclaim. */ |
83 | if (!igrab(inode)) | |
84 | return ENOENT; | |
85 | ||
86 | if (is_bad_inode(inode)) { | |
87 | IRELE(ip); | |
88 | return ENOENT; | |
89 | } | |
90 | ||
91 | /* inode is valid */ | |
92 | return 0; | |
1a3e8f3d DC |
93 | |
94 | out_unlock_noent: | |
95 | spin_unlock(&ip->i_flags_lock); | |
96 | return ENOENT; | |
e13de955 DC |
97 | } |
98 | ||
75f3cb13 DC |
99 | STATIC int |
100 | xfs_inode_ag_walk( | |
101 | struct xfs_mount *mp, | |
5017e97d | 102 | struct xfs_perag *pag, |
75f3cb13 DC |
103 | int (*execute)(struct xfs_inode *ip, |
104 | struct xfs_perag *pag, int flags), | |
65d0f205 | 105 | int flags) |
75f3cb13 | 106 | { |
75f3cb13 DC |
107 | uint32_t first_index; |
108 | int last_error = 0; | |
109 | int skipped; | |
65d0f205 | 110 | int done; |
78ae5256 | 111 | int nr_found; |
75f3cb13 DC |
112 | |
113 | restart: | |
65d0f205 | 114 | done = 0; |
75f3cb13 DC |
115 | skipped = 0; |
116 | first_index = 0; | |
78ae5256 | 117 | nr_found = 0; |
75f3cb13 | 118 | do { |
78ae5256 | 119 | struct xfs_inode *batch[XFS_LOOKUP_BATCH]; |
75f3cb13 | 120 | int error = 0; |
78ae5256 | 121 | int i; |
75f3cb13 | 122 | |
1a3e8f3d | 123 | rcu_read_lock(); |
65d0f205 | 124 | nr_found = radix_tree_gang_lookup(&pag->pag_ici_root, |
78ae5256 DC |
125 | (void **)batch, first_index, |
126 | XFS_LOOKUP_BATCH); | |
65d0f205 | 127 | if (!nr_found) { |
1a3e8f3d | 128 | rcu_read_unlock(); |
75f3cb13 | 129 | break; |
c8e20be0 | 130 | } |
75f3cb13 | 131 | |
65d0f205 | 132 | /* |
78ae5256 DC |
133 | * Grab the inodes before we drop the lock. if we found |
134 | * nothing, nr == 0 and the loop will be skipped. | |
65d0f205 | 135 | */ |
78ae5256 DC |
136 | for (i = 0; i < nr_found; i++) { |
137 | struct xfs_inode *ip = batch[i]; | |
138 | ||
139 | if (done || xfs_inode_ag_walk_grab(ip)) | |
140 | batch[i] = NULL; | |
141 | ||
142 | /* | |
1a3e8f3d DC |
143 | * Update the index for the next lookup. Catch |
144 | * overflows into the next AG range which can occur if | |
145 | * we have inodes in the last block of the AG and we | |
146 | * are currently pointing to the last inode. | |
147 | * | |
148 | * Because we may see inodes that are from the wrong AG | |
149 | * due to RCU freeing and reallocation, only update the | |
150 | * index if it lies in this AG. It was a race that lead | |
151 | * us to see this inode, so another lookup from the | |
152 | * same index will not find it again. | |
78ae5256 | 153 | */ |
1a3e8f3d DC |
154 | if (XFS_INO_TO_AGNO(mp, ip->i_ino) != pag->pag_agno) |
155 | continue; | |
78ae5256 DC |
156 | first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1); |
157 | if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino)) | |
158 | done = 1; | |
e13de955 | 159 | } |
78ae5256 DC |
160 | |
161 | /* unlock now we've grabbed the inodes. */ | |
1a3e8f3d | 162 | rcu_read_unlock(); |
e13de955 | 163 | |
78ae5256 DC |
164 | for (i = 0; i < nr_found; i++) { |
165 | if (!batch[i]) | |
166 | continue; | |
167 | error = execute(batch[i], pag, flags); | |
168 | IRELE(batch[i]); | |
169 | if (error == EAGAIN) { | |
170 | skipped++; | |
171 | continue; | |
172 | } | |
173 | if (error && last_error != EFSCORRUPTED) | |
174 | last_error = error; | |
75f3cb13 | 175 | } |
c8e20be0 DC |
176 | |
177 | /* bail out if the filesystem is corrupted. */ | |
75f3cb13 DC |
178 | if (error == EFSCORRUPTED) |
179 | break; | |
180 | ||
8daaa831 DC |
181 | cond_resched(); |
182 | ||
78ae5256 | 183 | } while (nr_found && !done); |
75f3cb13 DC |
184 | |
185 | if (skipped) { | |
186 | delay(1); | |
187 | goto restart; | |
188 | } | |
75f3cb13 DC |
189 | return last_error; |
190 | } | |
191 | ||
fe588ed3 | 192 | int |
75f3cb13 DC |
193 | xfs_inode_ag_iterator( |
194 | struct xfs_mount *mp, | |
195 | int (*execute)(struct xfs_inode *ip, | |
196 | struct xfs_perag *pag, int flags), | |
65d0f205 | 197 | int flags) |
75f3cb13 | 198 | { |
16fd5367 | 199 | struct xfs_perag *pag; |
75f3cb13 DC |
200 | int error = 0; |
201 | int last_error = 0; | |
202 | xfs_agnumber_t ag; | |
203 | ||
16fd5367 | 204 | ag = 0; |
65d0f205 DC |
205 | while ((pag = xfs_perag_get(mp, ag))) { |
206 | ag = pag->pag_agno + 1; | |
207 | error = xfs_inode_ag_walk(mp, pag, execute, flags); | |
5017e97d | 208 | xfs_perag_put(pag); |
75f3cb13 DC |
209 | if (error) { |
210 | last_error = error; | |
211 | if (error == EFSCORRUPTED) | |
212 | break; | |
213 | } | |
214 | } | |
215 | return XFS_ERROR(last_error); | |
216 | } | |
217 | ||
5a34d5cd DC |
218 | STATIC int |
219 | xfs_sync_inode_data( | |
220 | struct xfs_inode *ip, | |
75f3cb13 | 221 | struct xfs_perag *pag, |
5a34d5cd DC |
222 | int flags) |
223 | { | |
224 | struct inode *inode = VFS_I(ip); | |
225 | struct address_space *mapping = inode->i_mapping; | |
226 | int error = 0; | |
227 | ||
228 | if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) | |
4a06fd26 | 229 | return 0; |
5a34d5cd DC |
230 | |
231 | if (!xfs_ilock_nowait(ip, XFS_IOLOCK_SHARED)) { | |
232 | if (flags & SYNC_TRYLOCK) | |
4a06fd26 | 233 | return 0; |
5a34d5cd DC |
234 | xfs_ilock(ip, XFS_IOLOCK_SHARED); |
235 | } | |
236 | ||
237 | error = xfs_flush_pages(ip, 0, -1, (flags & SYNC_WAIT) ? | |
0cadda1c | 238 | 0 : XBF_ASYNC, FI_NONE); |
5a34d5cd | 239 | xfs_iunlock(ip, XFS_IOLOCK_SHARED); |
5a34d5cd DC |
240 | return error; |
241 | } | |
242 | ||
075fe102 CH |
243 | /* |
244 | * Write out pagecache data for the whole filesystem. | |
245 | */ | |
64c86149 | 246 | STATIC int |
075fe102 CH |
247 | xfs_sync_data( |
248 | struct xfs_mount *mp, | |
249 | int flags) | |
683a8970 | 250 | { |
075fe102 | 251 | int error; |
fe4fa4b8 | 252 | |
b0710ccc | 253 | ASSERT((flags & ~(SYNC_TRYLOCK|SYNC_WAIT)) == 0); |
fe4fa4b8 | 254 | |
65d0f205 | 255 | error = xfs_inode_ag_iterator(mp, xfs_sync_inode_data, flags); |
075fe102 CH |
256 | if (error) |
257 | return XFS_ERROR(error); | |
e9f1c6ee | 258 | |
a14a348b | 259 | xfs_log_force(mp, (flags & SYNC_WAIT) ? XFS_LOG_SYNC : 0); |
075fe102 CH |
260 | return 0; |
261 | } | |
e9f1c6ee | 262 | |
5d77c0dc | 263 | STATIC int |
2af75df7 | 264 | xfs_sync_fsdata( |
df308bcf | 265 | struct xfs_mount *mp) |
2af75df7 CH |
266 | { |
267 | struct xfs_buf *bp; | |
c2b006c1 | 268 | int error; |
2af75df7 CH |
269 | |
270 | /* | |
df308bcf CH |
271 | * If the buffer is pinned then push on the log so we won't get stuck |
272 | * waiting in the write for someone, maybe ourselves, to flush the log. | |
273 | * | |
274 | * Even though we just pushed the log above, we did not have the | |
275 | * superblock buffer locked at that point so it can become pinned in | |
276 | * between there and here. | |
2af75df7 | 277 | */ |
df308bcf | 278 | bp = xfs_getsb(mp, 0); |
811e64c7 | 279 | if (xfs_buf_ispinned(bp)) |
df308bcf | 280 | xfs_log_force(mp, 0); |
c2b006c1 CH |
281 | error = xfs_bwrite(bp); |
282 | xfs_buf_relse(bp); | |
283 | return error; | |
e9f1c6ee DC |
284 | } |
285 | ||
286 | /* | |
a4e4c4f4 DC |
287 | * When remounting a filesystem read-only or freezing the filesystem, we have |
288 | * two phases to execute. This first phase is syncing the data before we | |
289 | * quiesce the filesystem, and the second is flushing all the inodes out after | |
290 | * we've waited for all the transactions created by the first phase to | |
291 | * complete. The second phase ensures that the inodes are written to their | |
292 | * location on disk rather than just existing in transactions in the log. This | |
293 | * means after a quiesce there is no log replay required to write the inodes to | |
294 | * disk (this is the main difference between a sync and a quiesce). | |
295 | */ | |
296 | /* | |
297 | * First stage of freeze - no writers will make progress now we are here, | |
e9f1c6ee DC |
298 | * so we flush delwri and delalloc buffers here, then wait for all I/O to |
299 | * complete. Data is frozen at that point. Metadata is not frozen, | |
211e4d43 | 300 | * transactions can still occur here so don't bother emptying the AIL |
a4e4c4f4 | 301 | * because it'll just get dirty again. |
e9f1c6ee DC |
302 | */ |
303 | int | |
304 | xfs_quiesce_data( | |
305 | struct xfs_mount *mp) | |
306 | { | |
df308bcf | 307 | int error, error2 = 0; |
e9f1c6ee | 308 | |
34625c66 | 309 | /* force out the log */ |
33b8f7c2 CH |
310 | xfs_log_force(mp, XFS_LOG_SYNC); |
311 | ||
a4e4c4f4 | 312 | /* write superblock and hoover up shutdown errors */ |
df308bcf CH |
313 | error = xfs_sync_fsdata(mp); |
314 | ||
df308bcf CH |
315 | /* mark the log as covered if needed */ |
316 | if (xfs_log_need_covered(mp)) | |
c58efdb4 | 317 | error2 = xfs_fs_log_dummy(mp); |
e9f1c6ee | 318 | |
df308bcf | 319 | return error ? error : error2; |
2af75df7 CH |
320 | } |
321 | ||
76bf105c DC |
322 | /* |
323 | * Second stage of a quiesce. The data is already synced, now we have to take | |
324 | * care of the metadata. New transactions are already blocked, so we need to | |
25985edc | 325 | * wait for any remaining transactions to drain out before proceeding. |
76bf105c DC |
326 | */ |
327 | void | |
328 | xfs_quiesce_attr( | |
329 | struct xfs_mount *mp) | |
330 | { | |
331 | int error = 0; | |
332 | ||
333 | /* wait for all modifications to complete */ | |
334 | while (atomic_read(&mp->m_active_trans) > 0) | |
335 | delay(100); | |
336 | ||
211e4d43 CH |
337 | /* reclaim inodes to do any IO before the freeze completes */ |
338 | xfs_reclaim_inodes(mp, 0); | |
339 | xfs_reclaim_inodes(mp, SYNC_WAIT); | |
340 | ||
341 | /* flush all pending changes from the AIL */ | |
342 | xfs_ail_push_all_sync(mp->m_ail); | |
76bf105c | 343 | |
5e106572 FB |
344 | /* |
345 | * Just warn here till VFS can correctly support | |
346 | * read-only remount without racing. | |
347 | */ | |
348 | WARN_ON(atomic_read(&mp->m_active_trans) != 0); | |
76bf105c DC |
349 | |
350 | /* Push the superblock and write an unmount record */ | |
adab0f67 | 351 | error = xfs_log_sbcount(mp); |
76bf105c | 352 | if (error) |
4f10700a | 353 | xfs_warn(mp, "xfs_attr_quiesce: failed to log sb changes. " |
76bf105c DC |
354 | "Frozen image may not be consistent."); |
355 | xfs_log_unmount_write(mp); | |
211e4d43 CH |
356 | |
357 | /* | |
358 | * At this point we might have modified the superblock again and thus | |
359 | * added an item to the AIL, thus flush it again. | |
360 | */ | |
361 | xfs_ail_push_all_sync(mp->m_ail); | |
76bf105c DC |
362 | } |
363 | ||
c6d09b66 DC |
364 | static void |
365 | xfs_syncd_queue_sync( | |
366 | struct xfs_mount *mp) | |
a167b17e | 367 | { |
c6d09b66 DC |
368 | queue_delayed_work(xfs_syncd_wq, &mp->m_sync_work, |
369 | msecs_to_jiffies(xfs_syncd_centisecs * 10)); | |
a167b17e DC |
370 | } |
371 | ||
aacaa880 | 372 | /* |
df308bcf CH |
373 | * Every sync period we need to unpin all items, reclaim inodes and sync |
374 | * disk quotas. We might need to cover the log to indicate that the | |
1a387d3b | 375 | * filesystem is idle and not frozen. |
aacaa880 | 376 | */ |
a167b17e DC |
377 | STATIC void |
378 | xfs_sync_worker( | |
c6d09b66 | 379 | struct work_struct *work) |
a167b17e | 380 | { |
c6d09b66 DC |
381 | struct xfs_mount *mp = container_of(to_delayed_work(work), |
382 | struct xfs_mount, m_sync_work); | |
a167b17e DC |
383 | int error; |
384 | ||
8a00ebe4 DC |
385 | /* |
386 | * We shouldn't write/force the log if we are in the mount/unmount | |
387 | * process or on a read only filesystem. The workqueue still needs to be | |
388 | * active in both cases, however, because it is used for inode reclaim | |
11159a05 BM |
389 | * during these times. Use the MS_ACTIVE flag to avoid doing anything |
390 | * during mount. Doing work during unmount is avoided by calling | |
391 | * cancel_delayed_work_sync on this work queue before tearing down | |
392 | * the ail and the log in xfs_log_unmount. | |
8a00ebe4 | 393 | */ |
11159a05 BM |
394 | if (!(mp->m_super->s_flags & MS_ACTIVE) && |
395 | !(mp->m_flags & XFS_MOUNT_RDONLY)) { | |
396 | /* dgc: errors ignored here */ | |
397 | if (mp->m_super->s_frozen == SB_UNFROZEN && | |
398 | xfs_log_need_covered(mp)) | |
399 | error = xfs_fs_log_dummy(mp); | |
400 | else | |
401 | xfs_log_force(mp, 0); | |
402 | ||
403 | /* start pushing all the metadata that is currently | |
404 | * dirty */ | |
405 | xfs_ail_push_all(mp->m_ail); | |
aacaa880 | 406 | } |
c6d09b66 DC |
407 | |
408 | /* queue us up again */ | |
409 | xfs_syncd_queue_sync(mp); | |
a167b17e DC |
410 | } |
411 | ||
a7b339f1 DC |
412 | /* |
413 | * Queue a new inode reclaim pass if there are reclaimable inodes and there | |
414 | * isn't a reclaim pass already in progress. By default it runs every 5s based | |
415 | * on the xfs syncd work default of 30s. Perhaps this should have it's own | |
416 | * tunable, but that can be done if this method proves to be ineffective or too | |
417 | * aggressive. | |
418 | */ | |
419 | static void | |
420 | xfs_syncd_queue_reclaim( | |
421 | struct xfs_mount *mp) | |
a167b17e | 422 | { |
a167b17e | 423 | |
a7b339f1 DC |
424 | rcu_read_lock(); |
425 | if (radix_tree_tagged(&mp->m_perag_tree, XFS_ICI_RECLAIM_TAG)) { | |
426 | queue_delayed_work(xfs_syncd_wq, &mp->m_reclaim_work, | |
427 | msecs_to_jiffies(xfs_syncd_centisecs / 6 * 10)); | |
a167b17e | 428 | } |
a7b339f1 DC |
429 | rcu_read_unlock(); |
430 | } | |
a167b17e | 431 | |
a7b339f1 DC |
432 | /* |
433 | * This is a fast pass over the inode cache to try to get reclaim moving on as | |
434 | * many inodes as possible in a short period of time. It kicks itself every few | |
435 | * seconds, as well as being kicked by the inode cache shrinker when memory | |
436 | * goes low. It scans as quickly as possible avoiding locked inodes or those | |
437 | * already being flushed, and once done schedules a future pass. | |
438 | */ | |
439 | STATIC void | |
440 | xfs_reclaim_worker( | |
441 | struct work_struct *work) | |
442 | { | |
443 | struct xfs_mount *mp = container_of(to_delayed_work(work), | |
444 | struct xfs_mount, m_reclaim_work); | |
445 | ||
446 | xfs_reclaim_inodes(mp, SYNC_TRYLOCK); | |
447 | xfs_syncd_queue_reclaim(mp); | |
448 | } | |
449 | ||
89e4cb55 DC |
450 | /* |
451 | * Flush delayed allocate data, attempting to free up reserved space | |
452 | * from existing allocations. At this point a new allocation attempt | |
453 | * has failed with ENOSPC and we are in the process of scratching our | |
454 | * heads, looking about for more room. | |
455 | * | |
456 | * Queue a new data flush if there isn't one already in progress and | |
457 | * wait for completion of the flush. This means that we only ever have one | |
458 | * inode flush in progress no matter how many ENOSPC events are occurring and | |
459 | * so will prevent the system from bogging down due to every concurrent | |
460 | * ENOSPC event scanning all the active inodes in the system for writeback. | |
461 | */ | |
462 | void | |
463 | xfs_flush_inodes( | |
464 | struct xfs_inode *ip) | |
465 | { | |
466 | struct xfs_mount *mp = ip->i_mount; | |
467 | ||
468 | queue_work(xfs_syncd_wq, &mp->m_flush_work); | |
469 | flush_work_sync(&mp->m_flush_work); | |
470 | } | |
471 | ||
472 | STATIC void | |
473 | xfs_flush_worker( | |
474 | struct work_struct *work) | |
475 | { | |
476 | struct xfs_mount *mp = container_of(work, | |
477 | struct xfs_mount, m_flush_work); | |
478 | ||
479 | xfs_sync_data(mp, SYNC_TRYLOCK); | |
480 | xfs_sync_data(mp, SYNC_TRYLOCK | SYNC_WAIT); | |
a167b17e DC |
481 | } |
482 | ||
483 | int | |
484 | xfs_syncd_init( | |
485 | struct xfs_mount *mp) | |
486 | { | |
89e4cb55 | 487 | INIT_WORK(&mp->m_flush_work, xfs_flush_worker); |
c6d09b66 | 488 | INIT_DELAYED_WORK(&mp->m_sync_work, xfs_sync_worker); |
a7b339f1 DC |
489 | INIT_DELAYED_WORK(&mp->m_reclaim_work, xfs_reclaim_worker); |
490 | ||
c6d09b66 DC |
491 | xfs_syncd_queue_sync(mp); |
492 | ||
a167b17e DC |
493 | return 0; |
494 | } | |
495 | ||
496 | void | |
497 | xfs_syncd_stop( | |
498 | struct xfs_mount *mp) | |
499 | { | |
c6d09b66 | 500 | cancel_delayed_work_sync(&mp->m_sync_work); |
a7b339f1 | 501 | cancel_delayed_work_sync(&mp->m_reclaim_work); |
89e4cb55 | 502 | cancel_work_sync(&mp->m_flush_work); |
a167b17e DC |
503 | } |
504 | ||
bc990f5c CH |
505 | void |
506 | __xfs_inode_set_reclaim_tag( | |
507 | struct xfs_perag *pag, | |
508 | struct xfs_inode *ip) | |
509 | { | |
510 | radix_tree_tag_set(&pag->pag_ici_root, | |
511 | XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino), | |
512 | XFS_ICI_RECLAIM_TAG); | |
16fd5367 DC |
513 | |
514 | if (!pag->pag_ici_reclaimable) { | |
515 | /* propagate the reclaim tag up into the perag radix tree */ | |
516 | spin_lock(&ip->i_mount->m_perag_lock); | |
517 | radix_tree_tag_set(&ip->i_mount->m_perag_tree, | |
518 | XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino), | |
519 | XFS_ICI_RECLAIM_TAG); | |
520 | spin_unlock(&ip->i_mount->m_perag_lock); | |
a7b339f1 DC |
521 | |
522 | /* schedule periodic background inode reclaim */ | |
523 | xfs_syncd_queue_reclaim(ip->i_mount); | |
524 | ||
16fd5367 DC |
525 | trace_xfs_perag_set_reclaim(ip->i_mount, pag->pag_agno, |
526 | -1, _RET_IP_); | |
527 | } | |
9bf729c0 | 528 | pag->pag_ici_reclaimable++; |
bc990f5c CH |
529 | } |
530 | ||
11654513 DC |
531 | /* |
532 | * We set the inode flag atomically with the radix tree tag. | |
533 | * Once we get tag lookups on the radix tree, this inode flag | |
534 | * can go away. | |
535 | */ | |
396beb85 DC |
536 | void |
537 | xfs_inode_set_reclaim_tag( | |
538 | xfs_inode_t *ip) | |
539 | { | |
5017e97d DC |
540 | struct xfs_mount *mp = ip->i_mount; |
541 | struct xfs_perag *pag; | |
396beb85 | 542 | |
5017e97d | 543 | pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino)); |
1a427ab0 | 544 | spin_lock(&pag->pag_ici_lock); |
396beb85 | 545 | spin_lock(&ip->i_flags_lock); |
bc990f5c | 546 | __xfs_inode_set_reclaim_tag(pag, ip); |
11654513 | 547 | __xfs_iflags_set(ip, XFS_IRECLAIMABLE); |
396beb85 | 548 | spin_unlock(&ip->i_flags_lock); |
1a427ab0 | 549 | spin_unlock(&pag->pag_ici_lock); |
5017e97d | 550 | xfs_perag_put(pag); |
396beb85 DC |
551 | } |
552 | ||
081003ff JW |
553 | STATIC void |
554 | __xfs_inode_clear_reclaim( | |
396beb85 DC |
555 | xfs_perag_t *pag, |
556 | xfs_inode_t *ip) | |
557 | { | |
9bf729c0 | 558 | pag->pag_ici_reclaimable--; |
16fd5367 DC |
559 | if (!pag->pag_ici_reclaimable) { |
560 | /* clear the reclaim tag from the perag radix tree */ | |
561 | spin_lock(&ip->i_mount->m_perag_lock); | |
562 | radix_tree_tag_clear(&ip->i_mount->m_perag_tree, | |
563 | XFS_INO_TO_AGNO(ip->i_mount, ip->i_ino), | |
564 | XFS_ICI_RECLAIM_TAG); | |
565 | spin_unlock(&ip->i_mount->m_perag_lock); | |
566 | trace_xfs_perag_clear_reclaim(ip->i_mount, pag->pag_agno, | |
567 | -1, _RET_IP_); | |
568 | } | |
396beb85 DC |
569 | } |
570 | ||
081003ff JW |
571 | void |
572 | __xfs_inode_clear_reclaim_tag( | |
573 | xfs_mount_t *mp, | |
574 | xfs_perag_t *pag, | |
575 | xfs_inode_t *ip) | |
576 | { | |
577 | radix_tree_tag_clear(&pag->pag_ici_root, | |
578 | XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG); | |
579 | __xfs_inode_clear_reclaim(pag, ip); | |
580 | } | |
581 | ||
e3a20c0b DC |
582 | /* |
583 | * Grab the inode for reclaim exclusively. | |
584 | * Return 0 if we grabbed it, non-zero otherwise. | |
585 | */ | |
586 | STATIC int | |
587 | xfs_reclaim_inode_grab( | |
588 | struct xfs_inode *ip, | |
589 | int flags) | |
590 | { | |
1a3e8f3d DC |
591 | ASSERT(rcu_read_lock_held()); |
592 | ||
593 | /* quick check for stale RCU freed inode */ | |
594 | if (!ip->i_ino) | |
595 | return 1; | |
e3a20c0b DC |
596 | |
597 | /* | |
474fce06 CH |
598 | * If we are asked for non-blocking operation, do unlocked checks to |
599 | * see if the inode already is being flushed or in reclaim to avoid | |
600 | * lock traffic. | |
e3a20c0b DC |
601 | */ |
602 | if ((flags & SYNC_TRYLOCK) && | |
474fce06 | 603 | __xfs_iflags_test(ip, XFS_IFLOCK | XFS_IRECLAIM)) |
e3a20c0b | 604 | return 1; |
e3a20c0b DC |
605 | |
606 | /* | |
607 | * The radix tree lock here protects a thread in xfs_iget from racing | |
608 | * with us starting reclaim on the inode. Once we have the | |
609 | * XFS_IRECLAIM flag set it will not touch us. | |
1a3e8f3d DC |
610 | * |
611 | * Due to RCU lookup, we may find inodes that have been freed and only | |
612 | * have XFS_IRECLAIM set. Indeed, we may see reallocated inodes that | |
613 | * aren't candidates for reclaim at all, so we must check the | |
614 | * XFS_IRECLAIMABLE is set first before proceeding to reclaim. | |
e3a20c0b DC |
615 | */ |
616 | spin_lock(&ip->i_flags_lock); | |
1a3e8f3d DC |
617 | if (!__xfs_iflags_test(ip, XFS_IRECLAIMABLE) || |
618 | __xfs_iflags_test(ip, XFS_IRECLAIM)) { | |
619 | /* not a reclaim candidate. */ | |
e3a20c0b DC |
620 | spin_unlock(&ip->i_flags_lock); |
621 | return 1; | |
622 | } | |
623 | __xfs_iflags_set(ip, XFS_IRECLAIM); | |
624 | spin_unlock(&ip->i_flags_lock); | |
625 | return 0; | |
626 | } | |
627 | ||
777df5af | 628 | /* |
8a48088f CH |
629 | * Inodes in different states need to be treated differently. The following |
630 | * table lists the inode states and the reclaim actions necessary: | |
777df5af DC |
631 | * |
632 | * inode state iflush ret required action | |
633 | * --------------- ---------- --------------- | |
634 | * bad - reclaim | |
635 | * shutdown EIO unpin and reclaim | |
636 | * clean, unpinned 0 reclaim | |
637 | * stale, unpinned 0 reclaim | |
c854363e DC |
638 | * clean, pinned(*) 0 requeue |
639 | * stale, pinned EAGAIN requeue | |
8a48088f CH |
640 | * dirty, async - requeue |
641 | * dirty, sync 0 reclaim | |
777df5af DC |
642 | * |
643 | * (*) dgc: I don't think the clean, pinned state is possible but it gets | |
644 | * handled anyway given the order of checks implemented. | |
645 | * | |
c854363e DC |
646 | * Also, because we get the flush lock first, we know that any inode that has |
647 | * been flushed delwri has had the flush completed by the time we check that | |
8a48088f | 648 | * the inode is clean. |
c854363e | 649 | * |
8a48088f CH |
650 | * Note that because the inode is flushed delayed write by AIL pushing, the |
651 | * flush lock may already be held here and waiting on it can result in very | |
652 | * long latencies. Hence for sync reclaims, where we wait on the flush lock, | |
653 | * the caller should push the AIL first before trying to reclaim inodes to | |
654 | * minimise the amount of time spent waiting. For background relaim, we only | |
655 | * bother to reclaim clean inodes anyway. | |
c854363e | 656 | * |
777df5af DC |
657 | * Hence the order of actions after gaining the locks should be: |
658 | * bad => reclaim | |
659 | * shutdown => unpin and reclaim | |
8a48088f | 660 | * pinned, async => requeue |
c854363e | 661 | * pinned, sync => unpin |
777df5af DC |
662 | * stale => reclaim |
663 | * clean => reclaim | |
8a48088f | 664 | * dirty, async => requeue |
c854363e | 665 | * dirty, sync => flush, wait and reclaim |
777df5af | 666 | */ |
75f3cb13 | 667 | STATIC int |
c8e20be0 | 668 | xfs_reclaim_inode( |
75f3cb13 DC |
669 | struct xfs_inode *ip, |
670 | struct xfs_perag *pag, | |
c8e20be0 | 671 | int sync_mode) |
fce08f2f | 672 | { |
4c46819a CH |
673 | struct xfs_buf *bp = NULL; |
674 | int error; | |
777df5af | 675 | |
1bfd8d04 DC |
676 | restart: |
677 | error = 0; | |
c8e20be0 | 678 | xfs_ilock(ip, XFS_ILOCK_EXCL); |
c854363e DC |
679 | if (!xfs_iflock_nowait(ip)) { |
680 | if (!(sync_mode & SYNC_WAIT)) | |
681 | goto out; | |
682 | xfs_iflock(ip); | |
683 | } | |
7a3be02b | 684 | |
777df5af DC |
685 | if (is_bad_inode(VFS_I(ip))) |
686 | goto reclaim; | |
687 | if (XFS_FORCED_SHUTDOWN(ip->i_mount)) { | |
688 | xfs_iunpin_wait(ip); | |
04913fdd | 689 | xfs_iflush_abort(ip, false); |
777df5af DC |
690 | goto reclaim; |
691 | } | |
c854363e | 692 | if (xfs_ipincount(ip)) { |
8a48088f CH |
693 | if (!(sync_mode & SYNC_WAIT)) |
694 | goto out_ifunlock; | |
777df5af | 695 | xfs_iunpin_wait(ip); |
c854363e | 696 | } |
777df5af DC |
697 | if (xfs_iflags_test(ip, XFS_ISTALE)) |
698 | goto reclaim; | |
699 | if (xfs_inode_clean(ip)) | |
700 | goto reclaim; | |
701 | ||
8a48088f CH |
702 | /* |
703 | * Never flush out dirty data during non-blocking reclaim, as it would | |
704 | * just contend with AIL pushing trying to do the same job. | |
705 | */ | |
706 | if (!(sync_mode & SYNC_WAIT)) | |
707 | goto out_ifunlock; | |
708 | ||
1bfd8d04 DC |
709 | /* |
710 | * Now we have an inode that needs flushing. | |
711 | * | |
4c46819a | 712 | * Note that xfs_iflush will never block on the inode buffer lock, as |
1bfd8d04 | 713 | * xfs_ifree_cluster() can lock the inode buffer before it locks the |
4c46819a CH |
714 | * ip->i_lock, and we are doing the exact opposite here. As a result, |
715 | * doing a blocking xfs_itobp() to get the cluster buffer would result | |
1bfd8d04 DC |
716 | * in an ABBA deadlock with xfs_ifree_cluster(). |
717 | * | |
718 | * As xfs_ifree_cluser() must gather all inodes that are active in the | |
719 | * cache to mark them stale, if we hit this case we don't actually want | |
720 | * to do IO here - we want the inode marked stale so we can simply | |
4c46819a CH |
721 | * reclaim it. Hence if we get an EAGAIN error here, just unlock the |
722 | * inode, back off and try again. Hopefully the next pass through will | |
723 | * see the stale flag set on the inode. | |
1bfd8d04 | 724 | */ |
4c46819a | 725 | error = xfs_iflush(ip, &bp); |
8a48088f CH |
726 | if (error == EAGAIN) { |
727 | xfs_iunlock(ip, XFS_ILOCK_EXCL); | |
728 | /* backoff longer than in xfs_ifree_cluster */ | |
729 | delay(2); | |
730 | goto restart; | |
c854363e | 731 | } |
c854363e | 732 | |
4c46819a CH |
733 | if (!error) { |
734 | error = xfs_bwrite(bp); | |
735 | xfs_buf_relse(bp); | |
736 | } | |
737 | ||
738 | xfs_iflock(ip); | |
777df5af DC |
739 | reclaim: |
740 | xfs_ifunlock(ip); | |
c8e20be0 | 741 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
2f11feab DC |
742 | |
743 | XFS_STATS_INC(xs_ig_reclaims); | |
744 | /* | |
745 | * Remove the inode from the per-AG radix tree. | |
746 | * | |
747 | * Because radix_tree_delete won't complain even if the item was never | |
748 | * added to the tree assert that it's been there before to catch | |
749 | * problems with the inode life time early on. | |
750 | */ | |
1a427ab0 | 751 | spin_lock(&pag->pag_ici_lock); |
2f11feab DC |
752 | if (!radix_tree_delete(&pag->pag_ici_root, |
753 | XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino))) | |
754 | ASSERT(0); | |
081003ff | 755 | __xfs_inode_clear_reclaim(pag, ip); |
1a427ab0 | 756 | spin_unlock(&pag->pag_ici_lock); |
2f11feab DC |
757 | |
758 | /* | |
759 | * Here we do an (almost) spurious inode lock in order to coordinate | |
760 | * with inode cache radix tree lookups. This is because the lookup | |
761 | * can reference the inodes in the cache without taking references. | |
762 | * | |
763 | * We make that OK here by ensuring that we wait until the inode is | |
ad637a10 | 764 | * unlocked after the lookup before we go ahead and free it. |
2f11feab | 765 | */ |
ad637a10 | 766 | xfs_ilock(ip, XFS_ILOCK_EXCL); |
2f11feab | 767 | xfs_qm_dqdetach(ip); |
ad637a10 | 768 | xfs_iunlock(ip, XFS_ILOCK_EXCL); |
2f11feab DC |
769 | |
770 | xfs_inode_free(ip); | |
ad637a10 | 771 | return error; |
8a48088f CH |
772 | |
773 | out_ifunlock: | |
774 | xfs_ifunlock(ip); | |
775 | out: | |
776 | xfs_iflags_clear(ip, XFS_IRECLAIM); | |
777 | xfs_iunlock(ip, XFS_ILOCK_EXCL); | |
778 | /* | |
779 | * We could return EAGAIN here to make reclaim rescan the inode tree in | |
780 | * a short while. However, this just burns CPU time scanning the tree | |
781 | * waiting for IO to complete and xfssyncd never goes back to the idle | |
782 | * state. Instead, return 0 to let the next scheduled background reclaim | |
783 | * attempt to reclaim the inode again. | |
784 | */ | |
785 | return 0; | |
7a3be02b DC |
786 | } |
787 | ||
65d0f205 DC |
788 | /* |
789 | * Walk the AGs and reclaim the inodes in them. Even if the filesystem is | |
790 | * corrupted, we still want to try to reclaim all the inodes. If we don't, | |
791 | * then a shut down during filesystem unmount reclaim walk leak all the | |
792 | * unreclaimed inodes. | |
793 | */ | |
794 | int | |
795 | xfs_reclaim_inodes_ag( | |
796 | struct xfs_mount *mp, | |
797 | int flags, | |
798 | int *nr_to_scan) | |
799 | { | |
800 | struct xfs_perag *pag; | |
801 | int error = 0; | |
802 | int last_error = 0; | |
803 | xfs_agnumber_t ag; | |
69b491c2 DC |
804 | int trylock = flags & SYNC_TRYLOCK; |
805 | int skipped; | |
65d0f205 | 806 | |
69b491c2 | 807 | restart: |
65d0f205 | 808 | ag = 0; |
69b491c2 | 809 | skipped = 0; |
65d0f205 DC |
810 | while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) { |
811 | unsigned long first_index = 0; | |
812 | int done = 0; | |
e3a20c0b | 813 | int nr_found = 0; |
65d0f205 DC |
814 | |
815 | ag = pag->pag_agno + 1; | |
816 | ||
69b491c2 DC |
817 | if (trylock) { |
818 | if (!mutex_trylock(&pag->pag_ici_reclaim_lock)) { | |
819 | skipped++; | |
f83282a8 | 820 | xfs_perag_put(pag); |
69b491c2 DC |
821 | continue; |
822 | } | |
823 | first_index = pag->pag_ici_reclaim_cursor; | |
824 | } else | |
825 | mutex_lock(&pag->pag_ici_reclaim_lock); | |
826 | ||
65d0f205 | 827 | do { |
e3a20c0b DC |
828 | struct xfs_inode *batch[XFS_LOOKUP_BATCH]; |
829 | int i; | |
65d0f205 | 830 | |
1a3e8f3d | 831 | rcu_read_lock(); |
e3a20c0b DC |
832 | nr_found = radix_tree_gang_lookup_tag( |
833 | &pag->pag_ici_root, | |
834 | (void **)batch, first_index, | |
835 | XFS_LOOKUP_BATCH, | |
65d0f205 DC |
836 | XFS_ICI_RECLAIM_TAG); |
837 | if (!nr_found) { | |
b2232219 | 838 | done = 1; |
1a3e8f3d | 839 | rcu_read_unlock(); |
65d0f205 DC |
840 | break; |
841 | } | |
842 | ||
843 | /* | |
e3a20c0b DC |
844 | * Grab the inodes before we drop the lock. if we found |
845 | * nothing, nr == 0 and the loop will be skipped. | |
65d0f205 | 846 | */ |
e3a20c0b DC |
847 | for (i = 0; i < nr_found; i++) { |
848 | struct xfs_inode *ip = batch[i]; | |
849 | ||
850 | if (done || xfs_reclaim_inode_grab(ip, flags)) | |
851 | batch[i] = NULL; | |
852 | ||
853 | /* | |
854 | * Update the index for the next lookup. Catch | |
855 | * overflows into the next AG range which can | |
856 | * occur if we have inodes in the last block of | |
857 | * the AG and we are currently pointing to the | |
858 | * last inode. | |
1a3e8f3d DC |
859 | * |
860 | * Because we may see inodes that are from the | |
861 | * wrong AG due to RCU freeing and | |
862 | * reallocation, only update the index if it | |
863 | * lies in this AG. It was a race that lead us | |
864 | * to see this inode, so another lookup from | |
865 | * the same index will not find it again. | |
e3a20c0b | 866 | */ |
1a3e8f3d DC |
867 | if (XFS_INO_TO_AGNO(mp, ip->i_ino) != |
868 | pag->pag_agno) | |
869 | continue; | |
e3a20c0b DC |
870 | first_index = XFS_INO_TO_AGINO(mp, ip->i_ino + 1); |
871 | if (first_index < XFS_INO_TO_AGINO(mp, ip->i_ino)) | |
872 | done = 1; | |
873 | } | |
65d0f205 | 874 | |
e3a20c0b | 875 | /* unlock now we've grabbed the inodes. */ |
1a3e8f3d | 876 | rcu_read_unlock(); |
e3a20c0b DC |
877 | |
878 | for (i = 0; i < nr_found; i++) { | |
879 | if (!batch[i]) | |
880 | continue; | |
881 | error = xfs_reclaim_inode(batch[i], pag, flags); | |
882 | if (error && last_error != EFSCORRUPTED) | |
883 | last_error = error; | |
884 | } | |
885 | ||
886 | *nr_to_scan -= XFS_LOOKUP_BATCH; | |
65d0f205 | 887 | |
8daaa831 DC |
888 | cond_resched(); |
889 | ||
e3a20c0b | 890 | } while (nr_found && !done && *nr_to_scan > 0); |
65d0f205 | 891 | |
69b491c2 DC |
892 | if (trylock && !done) |
893 | pag->pag_ici_reclaim_cursor = first_index; | |
894 | else | |
895 | pag->pag_ici_reclaim_cursor = 0; | |
896 | mutex_unlock(&pag->pag_ici_reclaim_lock); | |
65d0f205 DC |
897 | xfs_perag_put(pag); |
898 | } | |
69b491c2 DC |
899 | |
900 | /* | |
901 | * if we skipped any AG, and we still have scan count remaining, do | |
902 | * another pass this time using blocking reclaim semantics (i.e | |
903 | * waiting on the reclaim locks and ignoring the reclaim cursors). This | |
904 | * ensure that when we get more reclaimers than AGs we block rather | |
905 | * than spin trying to execute reclaim. | |
906 | */ | |
8daaa831 | 907 | if (skipped && (flags & SYNC_WAIT) && *nr_to_scan > 0) { |
69b491c2 DC |
908 | trylock = 0; |
909 | goto restart; | |
910 | } | |
65d0f205 DC |
911 | return XFS_ERROR(last_error); |
912 | } | |
913 | ||
7a3be02b DC |
914 | int |
915 | xfs_reclaim_inodes( | |
916 | xfs_mount_t *mp, | |
7a3be02b DC |
917 | int mode) |
918 | { | |
65d0f205 DC |
919 | int nr_to_scan = INT_MAX; |
920 | ||
921 | return xfs_reclaim_inodes_ag(mp, mode, &nr_to_scan); | |
9bf729c0 DC |
922 | } |
923 | ||
924 | /* | |
8daaa831 | 925 | * Scan a certain number of inodes for reclaim. |
a7b339f1 DC |
926 | * |
927 | * When called we make sure that there is a background (fast) inode reclaim in | |
8daaa831 | 928 | * progress, while we will throttle the speed of reclaim via doing synchronous |
a7b339f1 DC |
929 | * reclaim of inodes. That means if we come across dirty inodes, we wait for |
930 | * them to be cleaned, which we hope will not be very long due to the | |
931 | * background walker having already kicked the IO off on those dirty inodes. | |
9bf729c0 | 932 | */ |
8daaa831 DC |
933 | void |
934 | xfs_reclaim_inodes_nr( | |
935 | struct xfs_mount *mp, | |
936 | int nr_to_scan) | |
9bf729c0 | 937 | { |
8daaa831 DC |
938 | /* kick background reclaimer and push the AIL */ |
939 | xfs_syncd_queue_reclaim(mp); | |
940 | xfs_ail_push_all(mp->m_ail); | |
a7b339f1 | 941 | |
8daaa831 DC |
942 | xfs_reclaim_inodes_ag(mp, SYNC_TRYLOCK | SYNC_WAIT, &nr_to_scan); |
943 | } | |
9bf729c0 | 944 | |
8daaa831 DC |
945 | /* |
946 | * Return the number of reclaimable inodes in the filesystem for | |
947 | * the shrinker to determine how much to reclaim. | |
948 | */ | |
949 | int | |
950 | xfs_reclaim_inodes_count( | |
951 | struct xfs_mount *mp) | |
952 | { | |
953 | struct xfs_perag *pag; | |
954 | xfs_agnumber_t ag = 0; | |
955 | int reclaimable = 0; | |
9bf729c0 | 956 | |
65d0f205 DC |
957 | while ((pag = xfs_perag_get_tag(mp, ag, XFS_ICI_RECLAIM_TAG))) { |
958 | ag = pag->pag_agno + 1; | |
70e60ce7 DC |
959 | reclaimable += pag->pag_ici_reclaimable; |
960 | xfs_perag_put(pag); | |
9bf729c0 | 961 | } |
9bf729c0 DC |
962 | return reclaimable; |
963 | } | |
964 |