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bc859611 DW |
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 "libxfs_priv.h" | |
21 | #include "xfs_fs.h" | |
22 | #include "xfs_shared.h" | |
23 | #include "xfs_format.h" | |
24 | #include "xfs_log_format.h" | |
25 | #include "xfs_trans_resv.h" | |
26 | #include "xfs_sb.h" | |
27 | #include "xfs_mount.h" | |
28 | #include "xfs_defer.h" | |
29 | #include "xfs_btree.h" | |
30 | #include "xfs_bmap.h" | |
31 | #include "xfs_refcount_btree.h" | |
32 | #include "xfs_alloc.h" | |
56d3fc2b | 33 | #include "xfs_errortag.h" |
bc859611 DW |
34 | #include "xfs_trace.h" |
35 | #include "xfs_cksum.h" | |
36 | #include "xfs_trans.h" | |
37 | #include "xfs_bit.h" | |
38 | #include "xfs_refcount.h" | |
10e65503 | 39 | #include "xfs_rmap.h" |
bc859611 | 40 | |
56ef8c33 DW |
41 | /* Allowable refcount adjustment amounts. */ |
42 | enum xfs_refc_adjust_op { | |
43 | XFS_REFCOUNT_ADJUST_INCREASE = 1, | |
44 | XFS_REFCOUNT_ADJUST_DECREASE = -1, | |
10e65503 DW |
45 | XFS_REFCOUNT_ADJUST_COW_ALLOC = 0, |
46 | XFS_REFCOUNT_ADJUST_COW_FREE = -1, | |
56ef8c33 DW |
47 | }; |
48 | ||
10e65503 DW |
49 | STATIC int __xfs_refcount_cow_alloc(struct xfs_btree_cur *rcur, |
50 | xfs_agblock_t agbno, xfs_extlen_t aglen, | |
51 | struct xfs_defer_ops *dfops); | |
52 | STATIC int __xfs_refcount_cow_free(struct xfs_btree_cur *rcur, | |
53 | xfs_agblock_t agbno, xfs_extlen_t aglen, | |
54 | struct xfs_defer_ops *dfops); | |
55 | ||
bc859611 DW |
56 | /* |
57 | * Look up the first record less than or equal to [bno, len] in the btree | |
58 | * given by cur. | |
59 | */ | |
60 | int | |
61 | xfs_refcount_lookup_le( | |
62 | struct xfs_btree_cur *cur, | |
63 | xfs_agblock_t bno, | |
64 | int *stat) | |
65 | { | |
66 | trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_private.a.agno, bno, | |
67 | XFS_LOOKUP_LE); | |
68 | cur->bc_rec.rc.rc_startblock = bno; | |
69 | cur->bc_rec.rc.rc_blockcount = 0; | |
70 | return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat); | |
71 | } | |
72 | ||
73 | /* | |
74 | * Look up the first record greater than or equal to [bno, len] in the btree | |
75 | * given by cur. | |
76 | */ | |
77 | int | |
78 | xfs_refcount_lookup_ge( | |
79 | struct xfs_btree_cur *cur, | |
80 | xfs_agblock_t bno, | |
81 | int *stat) | |
82 | { | |
83 | trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_private.a.agno, bno, | |
84 | XFS_LOOKUP_GE); | |
85 | cur->bc_rec.rc.rc_startblock = bno; | |
86 | cur->bc_rec.rc.rc_blockcount = 0; | |
87 | return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat); | |
88 | } | |
89 | ||
43e73fb0 DW |
90 | /* |
91 | * Look up the first record equal to [bno, len] in the btree | |
92 | * given by cur. | |
93 | */ | |
94 | int | |
95 | xfs_refcount_lookup_eq( | |
96 | struct xfs_btree_cur *cur, | |
97 | xfs_agblock_t bno, | |
98 | int *stat) | |
99 | { | |
100 | trace_xfs_refcount_lookup(cur->bc_mp, cur->bc_private.a.agno, bno, | |
101 | XFS_LOOKUP_LE); | |
102 | cur->bc_rec.rc.rc_startblock = bno; | |
103 | cur->bc_rec.rc.rc_blockcount = 0; | |
104 | return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat); | |
105 | } | |
106 | ||
10e65503 | 107 | /* Convert on-disk record to in-core format. */ |
aa465192 | 108 | void |
10e65503 DW |
109 | xfs_refcount_btrec_to_irec( |
110 | union xfs_btree_rec *rec, | |
111 | struct xfs_refcount_irec *irec) | |
112 | { | |
113 | irec->rc_startblock = be32_to_cpu(rec->refc.rc_startblock); | |
114 | irec->rc_blockcount = be32_to_cpu(rec->refc.rc_blockcount); | |
115 | irec->rc_refcount = be32_to_cpu(rec->refc.rc_refcount); | |
116 | } | |
117 | ||
bc859611 DW |
118 | /* |
119 | * Get the data from the pointed-to record. | |
120 | */ | |
121 | int | |
122 | xfs_refcount_get_rec( | |
123 | struct xfs_btree_cur *cur, | |
124 | struct xfs_refcount_irec *irec, | |
125 | int *stat) | |
126 | { | |
10e65503 DW |
127 | union xfs_btree_rec *rec; |
128 | int error; | |
bc859611 DW |
129 | |
130 | error = xfs_btree_get_rec(cur, &rec, stat); | |
131 | if (!error && *stat == 1) { | |
10e65503 | 132 | xfs_refcount_btrec_to_irec(rec, irec); |
bc859611 DW |
133 | trace_xfs_refcount_get(cur->bc_mp, cur->bc_private.a.agno, |
134 | irec); | |
135 | } | |
136 | return error; | |
137 | } | |
138 | ||
139 | /* | |
140 | * Update the record referred to by cur to the value given | |
141 | * by [bno, len, refcount]. | |
142 | * This either works (return 0) or gets an EFSCORRUPTED error. | |
143 | */ | |
144 | STATIC int | |
145 | xfs_refcount_update( | |
146 | struct xfs_btree_cur *cur, | |
147 | struct xfs_refcount_irec *irec) | |
148 | { | |
149 | union xfs_btree_rec rec; | |
150 | int error; | |
151 | ||
152 | trace_xfs_refcount_update(cur->bc_mp, cur->bc_private.a.agno, irec); | |
153 | rec.refc.rc_startblock = cpu_to_be32(irec->rc_startblock); | |
154 | rec.refc.rc_blockcount = cpu_to_be32(irec->rc_blockcount); | |
155 | rec.refc.rc_refcount = cpu_to_be32(irec->rc_refcount); | |
156 | error = xfs_btree_update(cur, &rec); | |
157 | if (error) | |
158 | trace_xfs_refcount_update_error(cur->bc_mp, | |
159 | cur->bc_private.a.agno, error, _RET_IP_); | |
160 | return error; | |
161 | } | |
162 | ||
163 | /* | |
164 | * Insert the record referred to by cur to the value given | |
165 | * by [bno, len, refcount]. | |
166 | * This either works (return 0) or gets an EFSCORRUPTED error. | |
167 | */ | |
aa465192 | 168 | int |
bc859611 DW |
169 | xfs_refcount_insert( |
170 | struct xfs_btree_cur *cur, | |
171 | struct xfs_refcount_irec *irec, | |
172 | int *i) | |
173 | { | |
174 | int error; | |
175 | ||
176 | trace_xfs_refcount_insert(cur->bc_mp, cur->bc_private.a.agno, irec); | |
177 | cur->bc_rec.rc.rc_startblock = irec->rc_startblock; | |
178 | cur->bc_rec.rc.rc_blockcount = irec->rc_blockcount; | |
179 | cur->bc_rec.rc.rc_refcount = irec->rc_refcount; | |
180 | error = xfs_btree_insert(cur, i); | |
181 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, *i == 1, out_error); | |
182 | out_error: | |
183 | if (error) | |
184 | trace_xfs_refcount_insert_error(cur->bc_mp, | |
185 | cur->bc_private.a.agno, error, _RET_IP_); | |
186 | return error; | |
187 | } | |
188 | ||
189 | /* | |
190 | * Remove the record referred to by cur, then set the pointer to the spot | |
191 | * where the record could be re-inserted, in case we want to increment or | |
192 | * decrement the cursor. | |
193 | * This either works (return 0) or gets an EFSCORRUPTED error. | |
194 | */ | |
195 | STATIC int | |
196 | xfs_refcount_delete( | |
197 | struct xfs_btree_cur *cur, | |
198 | int *i) | |
199 | { | |
200 | struct xfs_refcount_irec irec; | |
201 | int found_rec; | |
202 | int error; | |
203 | ||
204 | error = xfs_refcount_get_rec(cur, &irec, &found_rec); | |
205 | if (error) | |
206 | goto out_error; | |
207 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
208 | trace_xfs_refcount_delete(cur->bc_mp, cur->bc_private.a.agno, &irec); | |
209 | error = xfs_btree_delete(cur, i); | |
210 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, *i == 1, out_error); | |
211 | if (error) | |
212 | goto out_error; | |
213 | error = xfs_refcount_lookup_ge(cur, irec.rc_startblock, &found_rec); | |
214 | out_error: | |
215 | if (error) | |
216 | trace_xfs_refcount_delete_error(cur->bc_mp, | |
217 | cur->bc_private.a.agno, error, _RET_IP_); | |
218 | return error; | |
219 | } | |
56ef8c33 DW |
220 | |
221 | /* | |
222 | * Adjusting the Reference Count | |
223 | * | |
224 | * As stated elsewhere, the reference count btree (refcbt) stores | |
225 | * >1 reference counts for extents of physical blocks. In this | |
226 | * operation, we're either raising or lowering the reference count of | |
227 | * some subrange stored in the tree: | |
228 | * | |
229 | * <------ adjustment range ------> | |
230 | * ----+ +---+-----+ +--+--------+--------- | |
231 | * 2 | | 3 | 4 | |17| 55 | 10 | |
232 | * ----+ +---+-----+ +--+--------+--------- | |
233 | * X axis is physical blocks number; | |
234 | * reference counts are the numbers inside the rectangles | |
235 | * | |
236 | * The first thing we need to do is to ensure that there are no | |
237 | * refcount extents crossing either boundary of the range to be | |
238 | * adjusted. For any extent that does cross a boundary, split it into | |
239 | * two extents so that we can increment the refcount of one of the | |
240 | * pieces later: | |
241 | * | |
242 | * <------ adjustment range ------> | |
243 | * ----+ +---+-----+ +--+--------+----+---- | |
244 | * 2 | | 3 | 2 | |17| 55 | 10 | 10 | |
245 | * ----+ +---+-----+ +--+--------+----+---- | |
246 | * | |
247 | * For this next step, let's assume that all the physical blocks in | |
248 | * the adjustment range are mapped to a file and are therefore in use | |
249 | * at least once. Therefore, we can infer that any gap in the | |
250 | * refcount tree within the adjustment range represents a physical | |
251 | * extent with refcount == 1: | |
252 | * | |
253 | * <------ adjustment range ------> | |
254 | * ----+---+---+-----+-+--+--------+----+---- | |
255 | * 2 |"1"| 3 | 2 |1|17| 55 | 10 | 10 | |
256 | * ----+---+---+-----+-+--+--------+----+---- | |
257 | * ^ | |
258 | * | |
259 | * For each extent that falls within the interval range, figure out | |
260 | * which extent is to the left or the right of that extent. Now we | |
261 | * have a left, current, and right extent. If the new reference count | |
262 | * of the center extent enables us to merge left, center, and right | |
263 | * into one record covering all three, do so. If the center extent is | |
264 | * at the left end of the range, abuts the left extent, and its new | |
265 | * reference count matches the left extent's record, then merge them. | |
266 | * If the center extent is at the right end of the range, abuts the | |
267 | * right extent, and the reference counts match, merge those. In the | |
268 | * example, we can left merge (assuming an increment operation): | |
269 | * | |
270 | * <------ adjustment range ------> | |
271 | * --------+---+-----+-+--+--------+----+---- | |
272 | * 2 | 3 | 2 |1|17| 55 | 10 | 10 | |
273 | * --------+---+-----+-+--+--------+----+---- | |
274 | * ^ | |
275 | * | |
276 | * For all other extents within the range, adjust the reference count | |
277 | * or delete it if the refcount falls below 2. If we were | |
278 | * incrementing, the end result looks like this: | |
279 | * | |
280 | * <------ adjustment range ------> | |
281 | * --------+---+-----+-+--+--------+----+---- | |
282 | * 2 | 4 | 3 |2|18| 56 | 11 | 10 | |
283 | * --------+---+-----+-+--+--------+----+---- | |
284 | * | |
285 | * The result of a decrement operation looks as such: | |
286 | * | |
287 | * <------ adjustment range ------> | |
288 | * ----+ +---+ +--+--------+----+---- | |
289 | * 2 | | 2 | |16| 54 | 9 | 10 | |
290 | * ----+ +---+ +--+--------+----+---- | |
291 | * DDDD 111111DD | |
292 | * | |
293 | * The blocks marked "D" are freed; the blocks marked "1" are only | |
294 | * referenced once and therefore the record is removed from the | |
295 | * refcount btree. | |
296 | */ | |
297 | ||
298 | /* Next block after this extent. */ | |
299 | static inline xfs_agblock_t | |
300 | xfs_refc_next( | |
301 | struct xfs_refcount_irec *rc) | |
302 | { | |
303 | return rc->rc_startblock + rc->rc_blockcount; | |
304 | } | |
305 | ||
306 | /* | |
307 | * Split a refcount extent that crosses agbno. | |
308 | */ | |
309 | STATIC int | |
310 | xfs_refcount_split_extent( | |
311 | struct xfs_btree_cur *cur, | |
312 | xfs_agblock_t agbno, | |
313 | bool *shape_changed) | |
314 | { | |
315 | struct xfs_refcount_irec rcext, tmp; | |
316 | int found_rec; | |
317 | int error; | |
318 | ||
319 | *shape_changed = false; | |
320 | error = xfs_refcount_lookup_le(cur, agbno, &found_rec); | |
321 | if (error) | |
322 | goto out_error; | |
323 | if (!found_rec) | |
324 | return 0; | |
325 | ||
326 | error = xfs_refcount_get_rec(cur, &rcext, &found_rec); | |
327 | if (error) | |
328 | goto out_error; | |
329 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
330 | if (rcext.rc_startblock == agbno || xfs_refc_next(&rcext) <= agbno) | |
331 | return 0; | |
332 | ||
333 | *shape_changed = true; | |
334 | trace_xfs_refcount_split_extent(cur->bc_mp, cur->bc_private.a.agno, | |
335 | &rcext, agbno); | |
336 | ||
337 | /* Establish the right extent. */ | |
338 | tmp = rcext; | |
339 | tmp.rc_startblock = agbno; | |
340 | tmp.rc_blockcount -= (agbno - rcext.rc_startblock); | |
341 | error = xfs_refcount_update(cur, &tmp); | |
342 | if (error) | |
343 | goto out_error; | |
344 | ||
345 | /* Insert the left extent. */ | |
346 | tmp = rcext; | |
347 | tmp.rc_blockcount = agbno - rcext.rc_startblock; | |
348 | error = xfs_refcount_insert(cur, &tmp, &found_rec); | |
349 | if (error) | |
350 | goto out_error; | |
351 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
352 | return error; | |
353 | ||
354 | out_error: | |
355 | trace_xfs_refcount_split_extent_error(cur->bc_mp, | |
356 | cur->bc_private.a.agno, error, _RET_IP_); | |
357 | return error; | |
358 | } | |
359 | ||
360 | /* | |
361 | * Merge the left, center, and right extents. | |
362 | */ | |
363 | STATIC int | |
364 | xfs_refcount_merge_center_extents( | |
365 | struct xfs_btree_cur *cur, | |
366 | struct xfs_refcount_irec *left, | |
367 | struct xfs_refcount_irec *center, | |
368 | struct xfs_refcount_irec *right, | |
369 | unsigned long long extlen, | |
56ef8c33 DW |
370 | xfs_extlen_t *aglen) |
371 | { | |
372 | int error; | |
373 | int found_rec; | |
374 | ||
375 | trace_xfs_refcount_merge_center_extents(cur->bc_mp, | |
376 | cur->bc_private.a.agno, left, center, right); | |
377 | ||
378 | /* | |
379 | * Make sure the center and right extents are not in the btree. | |
380 | * If the center extent was synthesized, the first delete call | |
381 | * removes the right extent and we skip the second deletion. | |
382 | * If center and right were in the btree, then the first delete | |
383 | * call removes the center and the second one removes the right | |
384 | * extent. | |
385 | */ | |
386 | error = xfs_refcount_lookup_ge(cur, center->rc_startblock, | |
387 | &found_rec); | |
388 | if (error) | |
389 | goto out_error; | |
390 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
391 | ||
392 | error = xfs_refcount_delete(cur, &found_rec); | |
393 | if (error) | |
394 | goto out_error; | |
395 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
396 | ||
397 | if (center->rc_refcount > 1) { | |
398 | error = xfs_refcount_delete(cur, &found_rec); | |
399 | if (error) | |
400 | goto out_error; | |
401 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
402 | out_error); | |
403 | } | |
404 | ||
405 | /* Enlarge the left extent. */ | |
406 | error = xfs_refcount_lookup_le(cur, left->rc_startblock, | |
407 | &found_rec); | |
408 | if (error) | |
409 | goto out_error; | |
410 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
411 | ||
412 | left->rc_blockcount = extlen; | |
413 | error = xfs_refcount_update(cur, left); | |
414 | if (error) | |
415 | goto out_error; | |
416 | ||
417 | *aglen = 0; | |
418 | return error; | |
419 | ||
420 | out_error: | |
421 | trace_xfs_refcount_merge_center_extents_error(cur->bc_mp, | |
422 | cur->bc_private.a.agno, error, _RET_IP_); | |
423 | return error; | |
424 | } | |
425 | ||
426 | /* | |
427 | * Merge with the left extent. | |
428 | */ | |
429 | STATIC int | |
430 | xfs_refcount_merge_left_extent( | |
431 | struct xfs_btree_cur *cur, | |
432 | struct xfs_refcount_irec *left, | |
433 | struct xfs_refcount_irec *cleft, | |
434 | xfs_agblock_t *agbno, | |
435 | xfs_extlen_t *aglen) | |
436 | { | |
437 | int error; | |
438 | int found_rec; | |
439 | ||
440 | trace_xfs_refcount_merge_left_extent(cur->bc_mp, | |
441 | cur->bc_private.a.agno, left, cleft); | |
442 | ||
443 | /* If the extent at agbno (cleft) wasn't synthesized, remove it. */ | |
444 | if (cleft->rc_refcount > 1) { | |
445 | error = xfs_refcount_lookup_le(cur, cleft->rc_startblock, | |
446 | &found_rec); | |
447 | if (error) | |
448 | goto out_error; | |
449 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
450 | out_error); | |
451 | ||
452 | error = xfs_refcount_delete(cur, &found_rec); | |
453 | if (error) | |
454 | goto out_error; | |
455 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
456 | out_error); | |
457 | } | |
458 | ||
459 | /* Enlarge the left extent. */ | |
460 | error = xfs_refcount_lookup_le(cur, left->rc_startblock, | |
461 | &found_rec); | |
462 | if (error) | |
463 | goto out_error; | |
464 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
465 | ||
466 | left->rc_blockcount += cleft->rc_blockcount; | |
467 | error = xfs_refcount_update(cur, left); | |
468 | if (error) | |
469 | goto out_error; | |
470 | ||
471 | *agbno += cleft->rc_blockcount; | |
472 | *aglen -= cleft->rc_blockcount; | |
473 | return error; | |
474 | ||
475 | out_error: | |
476 | trace_xfs_refcount_merge_left_extent_error(cur->bc_mp, | |
477 | cur->bc_private.a.agno, error, _RET_IP_); | |
478 | return error; | |
479 | } | |
480 | ||
481 | /* | |
482 | * Merge with the right extent. | |
483 | */ | |
484 | STATIC int | |
485 | xfs_refcount_merge_right_extent( | |
486 | struct xfs_btree_cur *cur, | |
487 | struct xfs_refcount_irec *right, | |
488 | struct xfs_refcount_irec *cright, | |
56ef8c33 DW |
489 | xfs_extlen_t *aglen) |
490 | { | |
491 | int error; | |
492 | int found_rec; | |
493 | ||
494 | trace_xfs_refcount_merge_right_extent(cur->bc_mp, | |
495 | cur->bc_private.a.agno, cright, right); | |
496 | ||
497 | /* | |
498 | * If the extent ending at agbno+aglen (cright) wasn't synthesized, | |
499 | * remove it. | |
500 | */ | |
501 | if (cright->rc_refcount > 1) { | |
502 | error = xfs_refcount_lookup_le(cur, cright->rc_startblock, | |
503 | &found_rec); | |
504 | if (error) | |
505 | goto out_error; | |
506 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
507 | out_error); | |
508 | ||
509 | error = xfs_refcount_delete(cur, &found_rec); | |
510 | if (error) | |
511 | goto out_error; | |
512 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
513 | out_error); | |
514 | } | |
515 | ||
516 | /* Enlarge the right extent. */ | |
517 | error = xfs_refcount_lookup_le(cur, right->rc_startblock, | |
518 | &found_rec); | |
519 | if (error) | |
520 | goto out_error; | |
521 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
522 | ||
523 | right->rc_startblock -= cright->rc_blockcount; | |
524 | right->rc_blockcount += cright->rc_blockcount; | |
525 | error = xfs_refcount_update(cur, right); | |
526 | if (error) | |
527 | goto out_error; | |
528 | ||
529 | *aglen -= cright->rc_blockcount; | |
530 | return error; | |
531 | ||
532 | out_error: | |
533 | trace_xfs_refcount_merge_right_extent_error(cur->bc_mp, | |
534 | cur->bc_private.a.agno, error, _RET_IP_); | |
535 | return error; | |
536 | } | |
537 | ||
10e65503 DW |
538 | #define XFS_FIND_RCEXT_SHARED 1 |
539 | #define XFS_FIND_RCEXT_COW 2 | |
56ef8c33 DW |
540 | /* |
541 | * Find the left extent and the one after it (cleft). This function assumes | |
542 | * that we've already split any extent crossing agbno. | |
543 | */ | |
544 | STATIC int | |
545 | xfs_refcount_find_left_extents( | |
546 | struct xfs_btree_cur *cur, | |
547 | struct xfs_refcount_irec *left, | |
548 | struct xfs_refcount_irec *cleft, | |
549 | xfs_agblock_t agbno, | |
10e65503 DW |
550 | xfs_extlen_t aglen, |
551 | int flags) | |
56ef8c33 DW |
552 | { |
553 | struct xfs_refcount_irec tmp; | |
554 | int error; | |
555 | int found_rec; | |
556 | ||
557 | left->rc_startblock = cleft->rc_startblock = NULLAGBLOCK; | |
558 | error = xfs_refcount_lookup_le(cur, agbno - 1, &found_rec); | |
559 | if (error) | |
560 | goto out_error; | |
561 | if (!found_rec) | |
562 | return 0; | |
563 | ||
564 | error = xfs_refcount_get_rec(cur, &tmp, &found_rec); | |
565 | if (error) | |
566 | goto out_error; | |
567 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
568 | ||
569 | if (xfs_refc_next(&tmp) != agbno) | |
570 | return 0; | |
10e65503 DW |
571 | if ((flags & XFS_FIND_RCEXT_SHARED) && tmp.rc_refcount < 2) |
572 | return 0; | |
573 | if ((flags & XFS_FIND_RCEXT_COW) && tmp.rc_refcount > 1) | |
574 | return 0; | |
56ef8c33 DW |
575 | /* We have a left extent; retrieve (or invent) the next right one */ |
576 | *left = tmp; | |
577 | ||
578 | error = xfs_btree_increment(cur, 0, &found_rec); | |
579 | if (error) | |
580 | goto out_error; | |
581 | if (found_rec) { | |
582 | error = xfs_refcount_get_rec(cur, &tmp, &found_rec); | |
583 | if (error) | |
584 | goto out_error; | |
585 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
586 | out_error); | |
587 | ||
588 | /* if tmp starts at the end of our range, just use that */ | |
589 | if (tmp.rc_startblock == agbno) | |
590 | *cleft = tmp; | |
591 | else { | |
592 | /* | |
593 | * There's a gap in the refcntbt at the start of the | |
594 | * range we're interested in (refcount == 1) so | |
595 | * synthesize the implied extent and pass it back. | |
596 | * We assume here that the agbno/aglen range was | |
597 | * passed in from a data fork extent mapping and | |
598 | * therefore is allocated to exactly one owner. | |
599 | */ | |
600 | cleft->rc_startblock = agbno; | |
601 | cleft->rc_blockcount = min(aglen, | |
602 | tmp.rc_startblock - agbno); | |
603 | cleft->rc_refcount = 1; | |
604 | } | |
605 | } else { | |
606 | /* | |
607 | * No extents, so pretend that there's one covering the whole | |
608 | * range. | |
609 | */ | |
610 | cleft->rc_startblock = agbno; | |
611 | cleft->rc_blockcount = aglen; | |
612 | cleft->rc_refcount = 1; | |
613 | } | |
614 | trace_xfs_refcount_find_left_extent(cur->bc_mp, cur->bc_private.a.agno, | |
615 | left, cleft, agbno); | |
616 | return error; | |
617 | ||
618 | out_error: | |
619 | trace_xfs_refcount_find_left_extent_error(cur->bc_mp, | |
620 | cur->bc_private.a.agno, error, _RET_IP_); | |
621 | return error; | |
622 | } | |
623 | ||
624 | /* | |
625 | * Find the right extent and the one before it (cright). This function | |
626 | * assumes that we've already split any extents crossing agbno + aglen. | |
627 | */ | |
628 | STATIC int | |
629 | xfs_refcount_find_right_extents( | |
630 | struct xfs_btree_cur *cur, | |
631 | struct xfs_refcount_irec *right, | |
632 | struct xfs_refcount_irec *cright, | |
633 | xfs_agblock_t agbno, | |
10e65503 DW |
634 | xfs_extlen_t aglen, |
635 | int flags) | |
56ef8c33 DW |
636 | { |
637 | struct xfs_refcount_irec tmp; | |
638 | int error; | |
639 | int found_rec; | |
640 | ||
641 | right->rc_startblock = cright->rc_startblock = NULLAGBLOCK; | |
642 | error = xfs_refcount_lookup_ge(cur, agbno + aglen, &found_rec); | |
643 | if (error) | |
644 | goto out_error; | |
645 | if (!found_rec) | |
646 | return 0; | |
647 | ||
648 | error = xfs_refcount_get_rec(cur, &tmp, &found_rec); | |
649 | if (error) | |
650 | goto out_error; | |
651 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, out_error); | |
652 | ||
653 | if (tmp.rc_startblock != agbno + aglen) | |
654 | return 0; | |
10e65503 DW |
655 | if ((flags & XFS_FIND_RCEXT_SHARED) && tmp.rc_refcount < 2) |
656 | return 0; | |
657 | if ((flags & XFS_FIND_RCEXT_COW) && tmp.rc_refcount > 1) | |
658 | return 0; | |
56ef8c33 DW |
659 | /* We have a right extent; retrieve (or invent) the next left one */ |
660 | *right = tmp; | |
661 | ||
662 | error = xfs_btree_decrement(cur, 0, &found_rec); | |
663 | if (error) | |
664 | goto out_error; | |
665 | if (found_rec) { | |
666 | error = xfs_refcount_get_rec(cur, &tmp, &found_rec); | |
667 | if (error) | |
668 | goto out_error; | |
669 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, found_rec == 1, | |
670 | out_error); | |
671 | ||
672 | /* if tmp ends at the end of our range, just use that */ | |
673 | if (xfs_refc_next(&tmp) == agbno + aglen) | |
674 | *cright = tmp; | |
675 | else { | |
676 | /* | |
677 | * There's a gap in the refcntbt at the end of the | |
678 | * range we're interested in (refcount == 1) so | |
679 | * create the implied extent and pass it back. | |
680 | * We assume here that the agbno/aglen range was | |
681 | * passed in from a data fork extent mapping and | |
682 | * therefore is allocated to exactly one owner. | |
683 | */ | |
684 | cright->rc_startblock = max(agbno, xfs_refc_next(&tmp)); | |
685 | cright->rc_blockcount = right->rc_startblock - | |
686 | cright->rc_startblock; | |
687 | cright->rc_refcount = 1; | |
688 | } | |
689 | } else { | |
690 | /* | |
691 | * No extents, so pretend that there's one covering the whole | |
692 | * range. | |
693 | */ | |
694 | cright->rc_startblock = agbno; | |
695 | cright->rc_blockcount = aglen; | |
696 | cright->rc_refcount = 1; | |
697 | } | |
698 | trace_xfs_refcount_find_right_extent(cur->bc_mp, cur->bc_private.a.agno, | |
699 | cright, right, agbno + aglen); | |
700 | return error; | |
701 | ||
702 | out_error: | |
703 | trace_xfs_refcount_find_right_extent_error(cur->bc_mp, | |
704 | cur->bc_private.a.agno, error, _RET_IP_); | |
705 | return error; | |
706 | } | |
707 | ||
708 | /* Is this extent valid? */ | |
709 | static inline bool | |
710 | xfs_refc_valid( | |
711 | struct xfs_refcount_irec *rc) | |
712 | { | |
713 | return rc->rc_startblock != NULLAGBLOCK; | |
714 | } | |
715 | ||
716 | /* | |
717 | * Try to merge with any extents on the boundaries of the adjustment range. | |
718 | */ | |
719 | STATIC int | |
720 | xfs_refcount_merge_extents( | |
721 | struct xfs_btree_cur *cur, | |
722 | xfs_agblock_t *agbno, | |
723 | xfs_extlen_t *aglen, | |
724 | enum xfs_refc_adjust_op adjust, | |
10e65503 | 725 | int flags, |
56ef8c33 DW |
726 | bool *shape_changed) |
727 | { | |
728 | struct xfs_refcount_irec left = {0}, cleft = {0}; | |
729 | struct xfs_refcount_irec cright = {0}, right = {0}; | |
730 | int error; | |
731 | unsigned long long ulen; | |
732 | bool cequal; | |
733 | ||
734 | *shape_changed = false; | |
735 | /* | |
736 | * Find the extent just below agbno [left], just above agbno [cleft], | |
737 | * just below (agbno + aglen) [cright], and just above (agbno + aglen) | |
738 | * [right]. | |
739 | */ | |
740 | error = xfs_refcount_find_left_extents(cur, &left, &cleft, *agbno, | |
10e65503 | 741 | *aglen, flags); |
56ef8c33 DW |
742 | if (error) |
743 | return error; | |
744 | error = xfs_refcount_find_right_extents(cur, &right, &cright, *agbno, | |
10e65503 | 745 | *aglen, flags); |
56ef8c33 DW |
746 | if (error) |
747 | return error; | |
748 | ||
749 | /* No left or right extent to merge; exit. */ | |
750 | if (!xfs_refc_valid(&left) && !xfs_refc_valid(&right)) | |
751 | return 0; | |
752 | ||
753 | cequal = (cleft.rc_startblock == cright.rc_startblock) && | |
754 | (cleft.rc_blockcount == cright.rc_blockcount); | |
755 | ||
756 | /* Try to merge left, cleft, and right. cleft must == cright. */ | |
757 | ulen = (unsigned long long)left.rc_blockcount + cleft.rc_blockcount + | |
758 | right.rc_blockcount; | |
759 | if (xfs_refc_valid(&left) && xfs_refc_valid(&right) && | |
760 | xfs_refc_valid(&cleft) && xfs_refc_valid(&cright) && cequal && | |
761 | left.rc_refcount == cleft.rc_refcount + adjust && | |
762 | right.rc_refcount == cleft.rc_refcount + adjust && | |
763 | ulen < MAXREFCEXTLEN) { | |
764 | *shape_changed = true; | |
765 | return xfs_refcount_merge_center_extents(cur, &left, &cleft, | |
1421de38 | 766 | &right, ulen, aglen); |
56ef8c33 DW |
767 | } |
768 | ||
769 | /* Try to merge left and cleft. */ | |
770 | ulen = (unsigned long long)left.rc_blockcount + cleft.rc_blockcount; | |
771 | if (xfs_refc_valid(&left) && xfs_refc_valid(&cleft) && | |
772 | left.rc_refcount == cleft.rc_refcount + adjust && | |
773 | ulen < MAXREFCEXTLEN) { | |
774 | *shape_changed = true; | |
775 | error = xfs_refcount_merge_left_extent(cur, &left, &cleft, | |
776 | agbno, aglen); | |
777 | if (error) | |
778 | return error; | |
779 | ||
780 | /* | |
781 | * If we just merged left + cleft and cleft == cright, | |
782 | * we no longer have a cright to merge with right. We're done. | |
783 | */ | |
784 | if (cequal) | |
785 | return 0; | |
786 | } | |
787 | ||
788 | /* Try to merge cright and right. */ | |
789 | ulen = (unsigned long long)right.rc_blockcount + cright.rc_blockcount; | |
790 | if (xfs_refc_valid(&right) && xfs_refc_valid(&cright) && | |
791 | right.rc_refcount == cright.rc_refcount + adjust && | |
792 | ulen < MAXREFCEXTLEN) { | |
793 | *shape_changed = true; | |
794 | return xfs_refcount_merge_right_extent(cur, &right, &cright, | |
1421de38 | 795 | aglen); |
56ef8c33 DW |
796 | } |
797 | ||
798 | return error; | |
799 | } | |
800 | ||
801 | /* | |
56ef8c33 DW |
802 | * XXX: This is a pretty hand-wavy estimate. The penalty for guessing |
803 | * true incorrectly is a shutdown FS; the penalty for guessing false | |
804 | * incorrectly is more transaction rolls than might be necessary. | |
805 | * Be conservative here. | |
806 | */ | |
807 | static bool | |
808 | xfs_refcount_still_have_space( | |
809 | struct xfs_btree_cur *cur) | |
810 | { | |
811 | unsigned long overhead; | |
812 | ||
813 | overhead = cur->bc_private.a.priv.refc.shape_changes * | |
814 | xfs_allocfree_log_count(cur->bc_mp, 1); | |
815 | overhead *= cur->bc_mp->m_sb.sb_blocksize; | |
816 | ||
817 | /* | |
818 | * Only allow 2 refcount extent updates per transaction if the | |
819 | * refcount continue update "error" has been injected. | |
820 | */ | |
821 | if (cur->bc_private.a.priv.refc.nr_ops > 2 && | |
822 | XFS_TEST_ERROR(false, cur->bc_mp, | |
e2a190dd | 823 | XFS_ERRTAG_REFCOUNT_CONTINUE_UPDATE)) |
56ef8c33 DW |
824 | return false; |
825 | ||
826 | if (cur->bc_private.a.priv.refc.nr_ops == 0) | |
827 | return true; | |
828 | else if (overhead > cur->bc_tp->t_log_res) | |
829 | return false; | |
830 | return cur->bc_tp->t_log_res - overhead > | |
594956fa | 831 | cur->bc_private.a.priv.refc.nr_ops * XFS_REFCOUNT_ITEM_OVERHEAD; |
56ef8c33 DW |
832 | } |
833 | ||
834 | /* | |
835 | * Adjust the refcounts of middle extents. At this point we should have | |
836 | * split extents that crossed the adjustment range; merged with adjacent | |
837 | * extents; and updated agbno/aglen to reflect the merges. Therefore, | |
838 | * all we have to do is update the extents inside [agbno, agbno + aglen]. | |
839 | */ | |
840 | STATIC int | |
841 | xfs_refcount_adjust_extents( | |
842 | struct xfs_btree_cur *cur, | |
843 | xfs_agblock_t *agbno, | |
844 | xfs_extlen_t *aglen, | |
845 | enum xfs_refc_adjust_op adj, | |
846 | struct xfs_defer_ops *dfops, | |
847 | struct xfs_owner_info *oinfo) | |
848 | { | |
849 | struct xfs_refcount_irec ext, tmp; | |
850 | int error; | |
851 | int found_rec, found_tmp; | |
852 | xfs_fsblock_t fsbno; | |
853 | ||
854 | /* Merging did all the work already. */ | |
855 | if (*aglen == 0) | |
856 | return 0; | |
857 | ||
858 | error = xfs_refcount_lookup_ge(cur, *agbno, &found_rec); | |
859 | if (error) | |
860 | goto out_error; | |
861 | ||
862 | while (*aglen > 0 && xfs_refcount_still_have_space(cur)) { | |
863 | error = xfs_refcount_get_rec(cur, &ext, &found_rec); | |
864 | if (error) | |
865 | goto out_error; | |
866 | if (!found_rec) { | |
867 | ext.rc_startblock = cur->bc_mp->m_sb.sb_agblocks; | |
868 | ext.rc_blockcount = 0; | |
869 | ext.rc_refcount = 0; | |
870 | } | |
871 | ||
872 | /* | |
873 | * Deal with a hole in the refcount tree; if a file maps to | |
874 | * these blocks and there's no refcountbt record, pretend that | |
875 | * there is one with refcount == 1. | |
876 | */ | |
877 | if (ext.rc_startblock != *agbno) { | |
878 | tmp.rc_startblock = *agbno; | |
879 | tmp.rc_blockcount = min(*aglen, | |
880 | ext.rc_startblock - *agbno); | |
881 | tmp.rc_refcount = 1 + adj; | |
882 | trace_xfs_refcount_modify_extent(cur->bc_mp, | |
883 | cur->bc_private.a.agno, &tmp); | |
884 | ||
885 | /* | |
886 | * Either cover the hole (increment) or | |
887 | * delete the range (decrement). | |
888 | */ | |
889 | if (tmp.rc_refcount) { | |
890 | error = xfs_refcount_insert(cur, &tmp, | |
891 | &found_tmp); | |
892 | if (error) | |
893 | goto out_error; | |
894 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
895 | found_tmp == 1, out_error); | |
896 | cur->bc_private.a.priv.refc.nr_ops++; | |
897 | } else { | |
898 | fsbno = XFS_AGB_TO_FSB(cur->bc_mp, | |
899 | cur->bc_private.a.agno, | |
900 | tmp.rc_startblock); | |
901 | xfs_bmap_add_free(cur->bc_mp, dfops, fsbno, | |
902 | tmp.rc_blockcount, oinfo); | |
903 | } | |
904 | ||
905 | (*agbno) += tmp.rc_blockcount; | |
906 | (*aglen) -= tmp.rc_blockcount; | |
907 | ||
908 | error = xfs_refcount_lookup_ge(cur, *agbno, | |
909 | &found_rec); | |
910 | if (error) | |
911 | goto out_error; | |
912 | } | |
913 | ||
914 | /* Stop if there's nothing left to modify */ | |
915 | if (*aglen == 0 || !xfs_refcount_still_have_space(cur)) | |
916 | break; | |
917 | ||
918 | /* | |
919 | * Adjust the reference count and either update the tree | |
920 | * (incr) or free the blocks (decr). | |
921 | */ | |
922 | if (ext.rc_refcount == MAXREFCOUNT) | |
923 | goto skip; | |
924 | ext.rc_refcount += adj; | |
925 | trace_xfs_refcount_modify_extent(cur->bc_mp, | |
926 | cur->bc_private.a.agno, &ext); | |
927 | if (ext.rc_refcount > 1) { | |
928 | error = xfs_refcount_update(cur, &ext); | |
929 | if (error) | |
930 | goto out_error; | |
931 | cur->bc_private.a.priv.refc.nr_ops++; | |
932 | } else if (ext.rc_refcount == 1) { | |
933 | error = xfs_refcount_delete(cur, &found_rec); | |
934 | if (error) | |
935 | goto out_error; | |
936 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
937 | found_rec == 1, out_error); | |
938 | cur->bc_private.a.priv.refc.nr_ops++; | |
939 | goto advloop; | |
940 | } else { | |
941 | fsbno = XFS_AGB_TO_FSB(cur->bc_mp, | |
942 | cur->bc_private.a.agno, | |
943 | ext.rc_startblock); | |
944 | xfs_bmap_add_free(cur->bc_mp, dfops, fsbno, | |
945 | ext.rc_blockcount, oinfo); | |
946 | } | |
947 | ||
948 | skip: | |
949 | error = xfs_btree_increment(cur, 0, &found_rec); | |
950 | if (error) | |
951 | goto out_error; | |
952 | ||
953 | advloop: | |
954 | (*agbno) += ext.rc_blockcount; | |
955 | (*aglen) -= ext.rc_blockcount; | |
956 | } | |
957 | ||
958 | return error; | |
959 | out_error: | |
960 | trace_xfs_refcount_modify_extent_error(cur->bc_mp, | |
961 | cur->bc_private.a.agno, error, _RET_IP_); | |
962 | return error; | |
963 | } | |
964 | ||
965 | /* Adjust the reference count of a range of AG blocks. */ | |
966 | STATIC int | |
967 | xfs_refcount_adjust( | |
968 | struct xfs_btree_cur *cur, | |
969 | xfs_agblock_t agbno, | |
970 | xfs_extlen_t aglen, | |
971 | xfs_agblock_t *new_agbno, | |
972 | xfs_extlen_t *new_aglen, | |
973 | enum xfs_refc_adjust_op adj, | |
974 | struct xfs_defer_ops *dfops, | |
975 | struct xfs_owner_info *oinfo) | |
976 | { | |
977 | bool shape_changed; | |
978 | int shape_changes = 0; | |
979 | int error; | |
980 | ||
981 | *new_agbno = agbno; | |
982 | *new_aglen = aglen; | |
983 | if (adj == XFS_REFCOUNT_ADJUST_INCREASE) | |
984 | trace_xfs_refcount_increase(cur->bc_mp, cur->bc_private.a.agno, | |
985 | agbno, aglen); | |
986 | else | |
987 | trace_xfs_refcount_decrease(cur->bc_mp, cur->bc_private.a.agno, | |
988 | agbno, aglen); | |
989 | ||
990 | /* | |
991 | * Ensure that no rcextents cross the boundary of the adjustment range. | |
992 | */ | |
993 | error = xfs_refcount_split_extent(cur, agbno, &shape_changed); | |
994 | if (error) | |
995 | goto out_error; | |
996 | if (shape_changed) | |
997 | shape_changes++; | |
998 | ||
999 | error = xfs_refcount_split_extent(cur, agbno + aglen, &shape_changed); | |
1000 | if (error) | |
1001 | goto out_error; | |
1002 | if (shape_changed) | |
1003 | shape_changes++; | |
1004 | ||
1005 | /* | |
1006 | * Try to merge with the left or right extents of the range. | |
1007 | */ | |
1008 | error = xfs_refcount_merge_extents(cur, new_agbno, new_aglen, adj, | |
10e65503 | 1009 | XFS_FIND_RCEXT_SHARED, &shape_changed); |
56ef8c33 DW |
1010 | if (error) |
1011 | goto out_error; | |
1012 | if (shape_changed) | |
1013 | shape_changes++; | |
1014 | if (shape_changes) | |
1015 | cur->bc_private.a.priv.refc.shape_changes++; | |
1016 | ||
1017 | /* Now that we've taken care of the ends, adjust the middle extents */ | |
1018 | error = xfs_refcount_adjust_extents(cur, new_agbno, new_aglen, | |
1019 | adj, dfops, oinfo); | |
1020 | if (error) | |
1021 | goto out_error; | |
1022 | ||
1023 | return 0; | |
1024 | ||
1025 | out_error: | |
1026 | trace_xfs_refcount_adjust_error(cur->bc_mp, cur->bc_private.a.agno, | |
1027 | error, _RET_IP_); | |
1028 | return error; | |
1029 | } | |
23a15a6c DW |
1030 | |
1031 | /* Clean up after calling xfs_refcount_finish_one. */ | |
1032 | void | |
1033 | xfs_refcount_finish_one_cleanup( | |
1034 | struct xfs_trans *tp, | |
1035 | struct xfs_btree_cur *rcur, | |
1036 | int error) | |
1037 | { | |
1038 | struct xfs_buf *agbp; | |
1039 | ||
1040 | if (rcur == NULL) | |
1041 | return; | |
1042 | agbp = rcur->bc_private.a.agbp; | |
1043 | xfs_btree_del_cursor(rcur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR); | |
1044 | if (error) | |
1045 | xfs_trans_brelse(tp, agbp); | |
1046 | } | |
1047 | ||
1048 | /* | |
1049 | * Process one of the deferred refcount operations. We pass back the | |
1050 | * btree cursor to maintain our lock on the btree between calls. | |
1051 | * This saves time and eliminates a buffer deadlock between the | |
1052 | * superblock and the AGF because we'll always grab them in the same | |
1053 | * order. | |
1054 | */ | |
1055 | int | |
1056 | xfs_refcount_finish_one( | |
1057 | struct xfs_trans *tp, | |
1058 | struct xfs_defer_ops *dfops, | |
1059 | enum xfs_refcount_intent_type type, | |
1060 | xfs_fsblock_t startblock, | |
1061 | xfs_extlen_t blockcount, | |
1062 | xfs_fsblock_t *new_fsb, | |
1063 | xfs_extlen_t *new_len, | |
1064 | struct xfs_btree_cur **pcur) | |
1065 | { | |
1066 | struct xfs_mount *mp = tp->t_mountp; | |
1067 | struct xfs_btree_cur *rcur; | |
1068 | struct xfs_buf *agbp = NULL; | |
1069 | int error = 0; | |
1070 | xfs_agnumber_t agno; | |
1071 | xfs_agblock_t bno; | |
1072 | xfs_agblock_t new_agbno; | |
1073 | unsigned long nr_ops = 0; | |
1074 | int shape_changes = 0; | |
1075 | ||
1076 | agno = XFS_FSB_TO_AGNO(mp, startblock); | |
1077 | ASSERT(agno != NULLAGNUMBER); | |
1078 | bno = XFS_FSB_TO_AGBNO(mp, startblock); | |
1079 | ||
1080 | trace_xfs_refcount_deferred(mp, XFS_FSB_TO_AGNO(mp, startblock), | |
1081 | type, XFS_FSB_TO_AGBNO(mp, startblock), | |
1082 | blockcount); | |
1083 | ||
1084 | if (XFS_TEST_ERROR(false, mp, | |
e2a190dd | 1085 | XFS_ERRTAG_REFCOUNT_FINISH_ONE)) |
23a15a6c DW |
1086 | return -EIO; |
1087 | ||
1088 | /* | |
1089 | * If we haven't gotten a cursor or the cursor AG doesn't match | |
1090 | * the startblock, get one now. | |
1091 | */ | |
1092 | rcur = *pcur; | |
1093 | if (rcur != NULL && rcur->bc_private.a.agno != agno) { | |
1094 | nr_ops = rcur->bc_private.a.priv.refc.nr_ops; | |
1095 | shape_changes = rcur->bc_private.a.priv.refc.shape_changes; | |
1096 | xfs_refcount_finish_one_cleanup(tp, rcur, 0); | |
1097 | rcur = NULL; | |
1098 | *pcur = NULL; | |
1099 | } | |
1100 | if (rcur == NULL) { | |
1101 | error = xfs_alloc_read_agf(tp->t_mountp, tp, agno, | |
1102 | XFS_ALLOC_FLAG_FREEING, &agbp); | |
1103 | if (error) | |
1104 | return error; | |
1105 | if (!agbp) | |
1106 | return -EFSCORRUPTED; | |
1107 | ||
1108 | rcur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, dfops); | |
1109 | if (!rcur) { | |
1110 | error = -ENOMEM; | |
1111 | goto out_cur; | |
1112 | } | |
1113 | rcur->bc_private.a.priv.refc.nr_ops = nr_ops; | |
1114 | rcur->bc_private.a.priv.refc.shape_changes = shape_changes; | |
1115 | } | |
1116 | *pcur = rcur; | |
1117 | ||
1118 | switch (type) { | |
1119 | case XFS_REFCOUNT_INCREASE: | |
1120 | error = xfs_refcount_adjust(rcur, bno, blockcount, &new_agbno, | |
1121 | new_len, XFS_REFCOUNT_ADJUST_INCREASE, dfops, NULL); | |
1122 | *new_fsb = XFS_AGB_TO_FSB(mp, agno, new_agbno); | |
1123 | break; | |
1124 | case XFS_REFCOUNT_DECREASE: | |
1125 | error = xfs_refcount_adjust(rcur, bno, blockcount, &new_agbno, | |
1126 | new_len, XFS_REFCOUNT_ADJUST_DECREASE, dfops, NULL); | |
1127 | *new_fsb = XFS_AGB_TO_FSB(mp, agno, new_agbno); | |
1128 | break; | |
10e65503 DW |
1129 | case XFS_REFCOUNT_ALLOC_COW: |
1130 | *new_fsb = startblock + blockcount; | |
1131 | *new_len = 0; | |
1132 | error = __xfs_refcount_cow_alloc(rcur, bno, blockcount, dfops); | |
1133 | break; | |
1134 | case XFS_REFCOUNT_FREE_COW: | |
1135 | *new_fsb = startblock + blockcount; | |
1136 | *new_len = 0; | |
1137 | error = __xfs_refcount_cow_free(rcur, bno, blockcount, dfops); | |
1138 | break; | |
23a15a6c DW |
1139 | default: |
1140 | ASSERT(0); | |
1141 | error = -EFSCORRUPTED; | |
1142 | } | |
1143 | if (!error && *new_len > 0) | |
1144 | trace_xfs_refcount_finish_one_leftover(mp, agno, type, | |
1145 | bno, blockcount, new_agbno, *new_len); | |
1146 | return error; | |
1147 | ||
1148 | out_cur: | |
1149 | xfs_trans_brelse(tp, agbp); | |
1150 | ||
1151 | return error; | |
1152 | } | |
1153 | ||
1154 | /* | |
1155 | * Record a refcount intent for later processing. | |
1156 | */ | |
1157 | static int | |
1158 | __xfs_refcount_add( | |
1159 | struct xfs_mount *mp, | |
1160 | struct xfs_defer_ops *dfops, | |
1161 | enum xfs_refcount_intent_type type, | |
1162 | xfs_fsblock_t startblock, | |
1163 | xfs_extlen_t blockcount) | |
1164 | { | |
1165 | struct xfs_refcount_intent *ri; | |
1166 | ||
1167 | trace_xfs_refcount_defer(mp, XFS_FSB_TO_AGNO(mp, startblock), | |
1168 | type, XFS_FSB_TO_AGBNO(mp, startblock), | |
1169 | blockcount); | |
1170 | ||
1171 | ri = kmem_alloc(sizeof(struct xfs_refcount_intent), | |
1172 | KM_SLEEP | KM_NOFS); | |
1173 | INIT_LIST_HEAD(&ri->ri_list); | |
1174 | ri->ri_type = type; | |
1175 | ri->ri_startblock = startblock; | |
1176 | ri->ri_blockcount = blockcount; | |
1177 | ||
1178 | xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_REFCOUNT, &ri->ri_list); | |
1179 | return 0; | |
1180 | } | |
1181 | ||
1182 | /* | |
1183 | * Increase the reference count of the blocks backing a file's extent. | |
1184 | */ | |
1185 | int | |
1186 | xfs_refcount_increase_extent( | |
1187 | struct xfs_mount *mp, | |
1188 | struct xfs_defer_ops *dfops, | |
1189 | struct xfs_bmbt_irec *PREV) | |
1190 | { | |
1191 | if (!xfs_sb_version_hasreflink(&mp->m_sb)) | |
1192 | return 0; | |
1193 | ||
1194 | return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_INCREASE, | |
1195 | PREV->br_startblock, PREV->br_blockcount); | |
1196 | } | |
1197 | ||
1198 | /* | |
1199 | * Decrease the reference count of the blocks backing a file's extent. | |
1200 | */ | |
1201 | int | |
1202 | xfs_refcount_decrease_extent( | |
1203 | struct xfs_mount *mp, | |
1204 | struct xfs_defer_ops *dfops, | |
1205 | struct xfs_bmbt_irec *PREV) | |
1206 | { | |
1207 | if (!xfs_sb_version_hasreflink(&mp->m_sb)) | |
1208 | return 0; | |
1209 | ||
1210 | return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_DECREASE, | |
1211 | PREV->br_startblock, PREV->br_blockcount); | |
1212 | } | |
94097330 DW |
1213 | |
1214 | /* | |
1215 | * Given an AG extent, find the lowest-numbered run of shared blocks | |
1216 | * within that range and return the range in fbno/flen. If | |
1217 | * find_end_of_shared is set, return the longest contiguous extent of | |
1218 | * shared blocks; if not, just return the first extent we find. If no | |
1219 | * shared blocks are found, fbno and flen will be set to NULLAGBLOCK | |
1220 | * and 0, respectively. | |
1221 | */ | |
1222 | int | |
1223 | xfs_refcount_find_shared( | |
1224 | struct xfs_btree_cur *cur, | |
1225 | xfs_agblock_t agbno, | |
1226 | xfs_extlen_t aglen, | |
1227 | xfs_agblock_t *fbno, | |
1228 | xfs_extlen_t *flen, | |
1229 | bool find_end_of_shared) | |
1230 | { | |
1231 | struct xfs_refcount_irec tmp; | |
1232 | int i; | |
1233 | int have; | |
1234 | int error; | |
1235 | ||
1236 | trace_xfs_refcount_find_shared(cur->bc_mp, cur->bc_private.a.agno, | |
1237 | agbno, aglen); | |
1238 | ||
1239 | /* By default, skip the whole range */ | |
1240 | *fbno = NULLAGBLOCK; | |
1241 | *flen = 0; | |
1242 | ||
1243 | /* Try to find a refcount extent that crosses the start */ | |
1244 | error = xfs_refcount_lookup_le(cur, agbno, &have); | |
1245 | if (error) | |
1246 | goto out_error; | |
1247 | if (!have) { | |
1248 | /* No left extent, look at the next one */ | |
1249 | error = xfs_btree_increment(cur, 0, &have); | |
1250 | if (error) | |
1251 | goto out_error; | |
1252 | if (!have) | |
1253 | goto done; | |
1254 | } | |
1255 | error = xfs_refcount_get_rec(cur, &tmp, &i); | |
1256 | if (error) | |
1257 | goto out_error; | |
1258 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, out_error); | |
1259 | ||
1260 | /* If the extent ends before the start, look at the next one */ | |
1261 | if (tmp.rc_startblock + tmp.rc_blockcount <= agbno) { | |
1262 | error = xfs_btree_increment(cur, 0, &have); | |
1263 | if (error) | |
1264 | goto out_error; | |
1265 | if (!have) | |
1266 | goto done; | |
1267 | error = xfs_refcount_get_rec(cur, &tmp, &i); | |
1268 | if (error) | |
1269 | goto out_error; | |
1270 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, out_error); | |
1271 | } | |
1272 | ||
1273 | /* If the extent starts after the range we want, bail out */ | |
1274 | if (tmp.rc_startblock >= agbno + aglen) | |
1275 | goto done; | |
1276 | ||
1277 | /* We found the start of a shared extent! */ | |
1278 | if (tmp.rc_startblock < agbno) { | |
1279 | tmp.rc_blockcount -= (agbno - tmp.rc_startblock); | |
1280 | tmp.rc_startblock = agbno; | |
1281 | } | |
1282 | ||
1283 | *fbno = tmp.rc_startblock; | |
1284 | *flen = min(tmp.rc_blockcount, agbno + aglen - *fbno); | |
1285 | if (!find_end_of_shared) | |
1286 | goto done; | |
1287 | ||
1288 | /* Otherwise, find the end of this shared extent */ | |
1289 | while (*fbno + *flen < agbno + aglen) { | |
1290 | error = xfs_btree_increment(cur, 0, &have); | |
1291 | if (error) | |
1292 | goto out_error; | |
1293 | if (!have) | |
1294 | break; | |
1295 | error = xfs_refcount_get_rec(cur, &tmp, &i); | |
1296 | if (error) | |
1297 | goto out_error; | |
1298 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, i == 1, out_error); | |
1299 | if (tmp.rc_startblock >= agbno + aglen || | |
1300 | tmp.rc_startblock != *fbno + *flen) | |
1301 | break; | |
1302 | *flen = min(*flen + tmp.rc_blockcount, agbno + aglen - *fbno); | |
1303 | } | |
1304 | ||
1305 | done: | |
1306 | trace_xfs_refcount_find_shared_result(cur->bc_mp, | |
1307 | cur->bc_private.a.agno, *fbno, *flen); | |
1308 | ||
1309 | out_error: | |
1310 | if (error) | |
1311 | trace_xfs_refcount_find_shared_error(cur->bc_mp, | |
1312 | cur->bc_private.a.agno, error, _RET_IP_); | |
1313 | return error; | |
1314 | } | |
10e65503 DW |
1315 | |
1316 | /* | |
1317 | * Recovering CoW Blocks After a Crash | |
1318 | * | |
1319 | * Due to the way that the copy on write mechanism works, there's a window of | |
1320 | * opportunity in which we can lose track of allocated blocks during a crash. | |
1321 | * Because CoW uses delayed allocation in the in-core CoW fork, writeback | |
1322 | * causes blocks to be allocated and stored in the CoW fork. The blocks are | |
1323 | * no longer in the free space btree but are not otherwise recorded anywhere | |
1324 | * until the write completes and the blocks are mapped into the file. A crash | |
1325 | * in between allocation and remapping results in the replacement blocks being | |
1326 | * lost. This situation is exacerbated by the CoW extent size hint because | |
1327 | * allocations can hang around for long time. | |
1328 | * | |
1329 | * However, there is a place where we can record these allocations before they | |
1330 | * become mappings -- the reference count btree. The btree does not record | |
1331 | * extents with refcount == 1, so we can record allocations with a refcount of | |
1332 | * 1. Blocks being used for CoW writeout cannot be shared, so there should be | |
1333 | * no conflict with shared block records. These mappings should be created | |
1334 | * when we allocate blocks to the CoW fork and deleted when they're removed | |
1335 | * from the CoW fork. | |
1336 | * | |
1337 | * Minor nit: records for in-progress CoW allocations and records for shared | |
1338 | * extents must never be merged, to preserve the property that (except for CoW | |
1339 | * allocations) there are no refcount btree entries with refcount == 1. The | |
1340 | * only time this could potentially happen is when unsharing a block that's | |
1341 | * adjacent to CoW allocations, so we must be careful to avoid this. | |
1342 | * | |
1343 | * At mount time we recover lost CoW allocations by searching the refcount | |
1344 | * btree for these refcount == 1 mappings. These represent CoW allocations | |
1345 | * that were in progress at the time the filesystem went down, so we can free | |
1346 | * them to get the space back. | |
1347 | * | |
1348 | * This mechanism is superior to creating EFIs for unmapped CoW extents for | |
1349 | * several reasons -- first, EFIs pin the tail of the log and would have to be | |
1350 | * periodically relogged to avoid filling up the log. Second, CoW completions | |
1351 | * will have to file an EFD and create new EFIs for whatever remains in the | |
1352 | * CoW fork; this partially takes care of (1) but extent-size reservations | |
1353 | * will have to periodically relog even if there's no writeout in progress. | |
1354 | * This can happen if the CoW extent size hint is set, which you really want. | |
1355 | * Third, EFIs cannot currently be automatically relogged into newer | |
1356 | * transactions to advance the log tail. Fourth, stuffing the log full of | |
1357 | * EFIs places an upper bound on the number of CoW allocations that can be | |
1358 | * held filesystem-wide at any given time. Recording them in the refcount | |
1359 | * btree doesn't require us to maintain any state in memory and doesn't pin | |
1360 | * the log. | |
1361 | */ | |
1362 | /* | |
1363 | * Adjust the refcounts of CoW allocations. These allocations are "magic" | |
1364 | * in that they're not referenced anywhere else in the filesystem, so we | |
1365 | * stash them in the refcount btree with a refcount of 1 until either file | |
1366 | * remapping (or CoW cancellation) happens. | |
1367 | */ | |
1368 | STATIC int | |
1369 | xfs_refcount_adjust_cow_extents( | |
1370 | struct xfs_btree_cur *cur, | |
1371 | xfs_agblock_t agbno, | |
1372 | xfs_extlen_t aglen, | |
1421de38 | 1373 | enum xfs_refc_adjust_op adj) |
10e65503 DW |
1374 | { |
1375 | struct xfs_refcount_irec ext, tmp; | |
1376 | int error; | |
1377 | int found_rec, found_tmp; | |
1378 | ||
1379 | if (aglen == 0) | |
1380 | return 0; | |
1381 | ||
1382 | /* Find any overlapping refcount records */ | |
1383 | error = xfs_refcount_lookup_ge(cur, agbno, &found_rec); | |
1384 | if (error) | |
1385 | goto out_error; | |
1386 | error = xfs_refcount_get_rec(cur, &ext, &found_rec); | |
1387 | if (error) | |
1388 | goto out_error; | |
1389 | if (!found_rec) { | |
1390 | ext.rc_startblock = cur->bc_mp->m_sb.sb_agblocks + | |
1391 | XFS_REFC_COW_START; | |
1392 | ext.rc_blockcount = 0; | |
1393 | ext.rc_refcount = 0; | |
1394 | } | |
1395 | ||
1396 | switch (adj) { | |
1397 | case XFS_REFCOUNT_ADJUST_COW_ALLOC: | |
1398 | /* Adding a CoW reservation, there should be nothing here. */ | |
1399 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1400 | ext.rc_startblock >= agbno + aglen, out_error); | |
1401 | ||
1402 | tmp.rc_startblock = agbno; | |
1403 | tmp.rc_blockcount = aglen; | |
1404 | tmp.rc_refcount = 1; | |
1405 | trace_xfs_refcount_modify_extent(cur->bc_mp, | |
1406 | cur->bc_private.a.agno, &tmp); | |
1407 | ||
1408 | error = xfs_refcount_insert(cur, &tmp, | |
1409 | &found_tmp); | |
1410 | if (error) | |
1411 | goto out_error; | |
1412 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1413 | found_tmp == 1, out_error); | |
1414 | break; | |
1415 | case XFS_REFCOUNT_ADJUST_COW_FREE: | |
1416 | /* Removing a CoW reservation, there should be one extent. */ | |
1417 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1418 | ext.rc_startblock == agbno, out_error); | |
1419 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1420 | ext.rc_blockcount == aglen, out_error); | |
1421 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1422 | ext.rc_refcount == 1, out_error); | |
1423 | ||
1424 | ext.rc_refcount = 0; | |
1425 | trace_xfs_refcount_modify_extent(cur->bc_mp, | |
1426 | cur->bc_private.a.agno, &ext); | |
1427 | error = xfs_refcount_delete(cur, &found_rec); | |
1428 | if (error) | |
1429 | goto out_error; | |
1430 | XFS_WANT_CORRUPTED_GOTO(cur->bc_mp, | |
1431 | found_rec == 1, out_error); | |
1432 | break; | |
1433 | default: | |
1434 | ASSERT(0); | |
1435 | } | |
1436 | ||
1437 | return error; | |
1438 | out_error: | |
1439 | trace_xfs_refcount_modify_extent_error(cur->bc_mp, | |
1440 | cur->bc_private.a.agno, error, _RET_IP_); | |
1441 | return error; | |
1442 | } | |
1443 | ||
1444 | /* | |
1445 | * Add or remove refcount btree entries for CoW reservations. | |
1446 | */ | |
1447 | STATIC int | |
1448 | xfs_refcount_adjust_cow( | |
1449 | struct xfs_btree_cur *cur, | |
1450 | xfs_agblock_t agbno, | |
1451 | xfs_extlen_t aglen, | |
1421de38 | 1452 | enum xfs_refc_adjust_op adj) |
10e65503 DW |
1453 | { |
1454 | bool shape_changed; | |
1455 | int error; | |
1456 | ||
1457 | agbno += XFS_REFC_COW_START; | |
1458 | ||
1459 | /* | |
1460 | * Ensure that no rcextents cross the boundary of the adjustment range. | |
1461 | */ | |
1462 | error = xfs_refcount_split_extent(cur, agbno, &shape_changed); | |
1463 | if (error) | |
1464 | goto out_error; | |
1465 | ||
1466 | error = xfs_refcount_split_extent(cur, agbno + aglen, &shape_changed); | |
1467 | if (error) | |
1468 | goto out_error; | |
1469 | ||
1470 | /* | |
1471 | * Try to merge with the left or right extents of the range. | |
1472 | */ | |
1473 | error = xfs_refcount_merge_extents(cur, &agbno, &aglen, adj, | |
1474 | XFS_FIND_RCEXT_COW, &shape_changed); | |
1475 | if (error) | |
1476 | goto out_error; | |
1477 | ||
1478 | /* Now that we've taken care of the ends, adjust the middle extents */ | |
1421de38 | 1479 | error = xfs_refcount_adjust_cow_extents(cur, agbno, aglen, adj); |
10e65503 DW |
1480 | if (error) |
1481 | goto out_error; | |
1482 | ||
1483 | return 0; | |
1484 | ||
1485 | out_error: | |
1486 | trace_xfs_refcount_adjust_cow_error(cur->bc_mp, cur->bc_private.a.agno, | |
1487 | error, _RET_IP_); | |
1488 | return error; | |
1489 | } | |
1490 | ||
1491 | /* | |
1492 | * Record a CoW allocation in the refcount btree. | |
1493 | */ | |
1494 | STATIC int | |
1495 | __xfs_refcount_cow_alloc( | |
1496 | struct xfs_btree_cur *rcur, | |
1497 | xfs_agblock_t agbno, | |
1498 | xfs_extlen_t aglen, | |
1499 | struct xfs_defer_ops *dfops) | |
1500 | { | |
10e65503 DW |
1501 | trace_xfs_refcount_cow_increase(rcur->bc_mp, rcur->bc_private.a.agno, |
1502 | agbno, aglen); | |
1503 | ||
1504 | /* Add refcount btree reservation */ | |
a44b23a0 | 1505 | return xfs_refcount_adjust_cow(rcur, agbno, aglen, |
1421de38 | 1506 | XFS_REFCOUNT_ADJUST_COW_ALLOC); |
10e65503 DW |
1507 | } |
1508 | ||
1509 | /* | |
1510 | * Remove a CoW allocation from the refcount btree. | |
1511 | */ | |
1512 | STATIC int | |
1513 | __xfs_refcount_cow_free( | |
1514 | struct xfs_btree_cur *rcur, | |
1515 | xfs_agblock_t agbno, | |
1516 | xfs_extlen_t aglen, | |
1517 | struct xfs_defer_ops *dfops) | |
1518 | { | |
10e65503 DW |
1519 | trace_xfs_refcount_cow_decrease(rcur->bc_mp, rcur->bc_private.a.agno, |
1520 | agbno, aglen); | |
1521 | ||
1522 | /* Remove refcount btree reservation */ | |
a44b23a0 | 1523 | return xfs_refcount_adjust_cow(rcur, agbno, aglen, |
1421de38 | 1524 | XFS_REFCOUNT_ADJUST_COW_FREE); |
10e65503 DW |
1525 | } |
1526 | ||
1527 | /* Record a CoW staging extent in the refcount btree. */ | |
1528 | int | |
1529 | xfs_refcount_alloc_cow_extent( | |
1530 | struct xfs_mount *mp, | |
1531 | struct xfs_defer_ops *dfops, | |
1532 | xfs_fsblock_t fsb, | |
1533 | xfs_extlen_t len) | |
1534 | { | |
a44b23a0 DW |
1535 | int error; |
1536 | ||
10e65503 DW |
1537 | if (!xfs_sb_version_hasreflink(&mp->m_sb)) |
1538 | return 0; | |
1539 | ||
a44b23a0 | 1540 | error = __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_ALLOC_COW, |
10e65503 | 1541 | fsb, len); |
a44b23a0 DW |
1542 | if (error) |
1543 | return error; | |
1544 | ||
1545 | /* Add rmap entry */ | |
1546 | return xfs_rmap_alloc_extent(mp, dfops, XFS_FSB_TO_AGNO(mp, fsb), | |
1547 | XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW); | |
10e65503 DW |
1548 | } |
1549 | ||
1550 | /* Forget a CoW staging event in the refcount btree. */ | |
1551 | int | |
1552 | xfs_refcount_free_cow_extent( | |
1553 | struct xfs_mount *mp, | |
1554 | struct xfs_defer_ops *dfops, | |
1555 | xfs_fsblock_t fsb, | |
1556 | xfs_extlen_t len) | |
1557 | { | |
a44b23a0 DW |
1558 | int error; |
1559 | ||
10e65503 DW |
1560 | if (!xfs_sb_version_hasreflink(&mp->m_sb)) |
1561 | return 0; | |
1562 | ||
a44b23a0 DW |
1563 | /* Remove rmap entry */ |
1564 | error = xfs_rmap_free_extent(mp, dfops, XFS_FSB_TO_AGNO(mp, fsb), | |
1565 | XFS_FSB_TO_AGBNO(mp, fsb), len, XFS_RMAP_OWN_COW); | |
1566 | if (error) | |
1567 | return error; | |
1568 | ||
10e65503 DW |
1569 | return __xfs_refcount_add(mp, dfops, XFS_REFCOUNT_FREE_COW, |
1570 | fsb, len); | |
1571 | } | |
1572 | ||
1573 | struct xfs_refcount_recovery { | |
1574 | struct list_head rr_list; | |
1575 | struct xfs_refcount_irec rr_rrec; | |
1576 | }; | |
1577 | ||
1578 | /* Stuff an extent on the recovery list. */ | |
1579 | STATIC int | |
1580 | xfs_refcount_recover_extent( | |
1421de38 | 1581 | struct xfs_btree_cur *cur, |
10e65503 DW |
1582 | union xfs_btree_rec *rec, |
1583 | void *priv) | |
1584 | { | |
1585 | struct list_head *debris = priv; | |
1586 | struct xfs_refcount_recovery *rr; | |
1587 | ||
1588 | if (be32_to_cpu(rec->refc.rc_refcount) != 1) | |
1589 | return -EFSCORRUPTED; | |
1590 | ||
1591 | rr = kmem_alloc(sizeof(struct xfs_refcount_recovery), KM_SLEEP); | |
1592 | xfs_refcount_btrec_to_irec(rec, &rr->rr_rrec); | |
1593 | list_add_tail(&rr->rr_list, debris); | |
1594 | ||
1595 | return 0; | |
1596 | } | |
1597 | ||
1598 | /* Find and remove leftover CoW reservations. */ | |
1599 | int | |
1600 | xfs_refcount_recover_cow_leftovers( | |
1601 | struct xfs_mount *mp, | |
1602 | xfs_agnumber_t agno) | |
1603 | { | |
1604 | struct xfs_trans *tp; | |
1605 | struct xfs_btree_cur *cur; | |
1606 | struct xfs_buf *agbp; | |
1607 | struct xfs_refcount_recovery *rr, *n; | |
1608 | struct list_head debris; | |
1609 | union xfs_btree_irec low; | |
1610 | union xfs_btree_irec high; | |
1611 | struct xfs_defer_ops dfops; | |
1612 | xfs_fsblock_t fsb; | |
1613 | xfs_agblock_t agbno; | |
1614 | int error; | |
1615 | ||
1616 | if (mp->m_sb.sb_agblocks >= XFS_REFC_COW_START) | |
1617 | return -EOPNOTSUPP; | |
1618 | ||
d4e8eb2e DW |
1619 | INIT_LIST_HEAD(&debris); |
1620 | ||
1621 | /* | |
1622 | * In this first part, we use an empty transaction to gather up | |
1623 | * all the leftover CoW extents so that we can subsequently | |
1624 | * delete them. The empty transaction is used to avoid | |
1625 | * a buffer lock deadlock if there happens to be a loop in the | |
1626 | * refcountbt because we're allowed to re-grab a buffer that is | |
1627 | * already attached to our transaction. When we're done | |
1628 | * recording the CoW debris we cancel the (empty) transaction | |
1629 | * and everything goes away cleanly. | |
1630 | */ | |
1631 | error = xfs_trans_alloc_empty(mp, &tp); | |
10e65503 DW |
1632 | if (error) |
1633 | return error; | |
d4e8eb2e DW |
1634 | |
1635 | error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp); | |
1636 | if (error) | |
1637 | goto out_trans; | |
d705962a DW |
1638 | if (!agbp) { |
1639 | error = -ENOMEM; | |
1640 | goto out_trans; | |
1641 | } | |
d4e8eb2e | 1642 | cur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, NULL); |
10e65503 DW |
1643 | |
1644 | /* Find all the leftover CoW staging extents. */ | |
10e65503 DW |
1645 | memset(&low, 0, sizeof(low)); |
1646 | memset(&high, 0, sizeof(high)); | |
1647 | low.rc.rc_startblock = XFS_REFC_COW_START; | |
1648 | high.rc.rc_startblock = -1U; | |
1649 | error = xfs_btree_query_range(cur, &low, &high, | |
1650 | xfs_refcount_recover_extent, &debris); | |
1651 | if (error) | |
22a69322 | 1652 | goto out_cursor; |
10e65503 | 1653 | xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR); |
d4e8eb2e DW |
1654 | xfs_trans_brelse(tp, agbp); |
1655 | xfs_trans_cancel(tp); | |
10e65503 DW |
1656 | |
1657 | /* Now iterate the list to free the leftovers */ | |
d4e8eb2e | 1658 | list_for_each_entry_safe(rr, n, &debris, rr_list) { |
10e65503 DW |
1659 | /* Set up transaction. */ |
1660 | error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp); | |
1661 | if (error) | |
1662 | goto out_free; | |
1663 | ||
1664 | trace_xfs_refcount_recover_extent(mp, agno, &rr->rr_rrec); | |
1665 | ||
1666 | /* Free the orphan record */ | |
1667 | xfs_defer_init(&dfops, &fsb); | |
1668 | agbno = rr->rr_rrec.rc_startblock - XFS_REFC_COW_START; | |
1669 | fsb = XFS_AGB_TO_FSB(mp, agno, agbno); | |
1670 | error = xfs_refcount_free_cow_extent(mp, &dfops, fsb, | |
1671 | rr->rr_rrec.rc_blockcount); | |
1672 | if (error) | |
1673 | goto out_defer; | |
1674 | ||
1675 | /* Free the block. */ | |
1676 | xfs_bmap_add_free(mp, &dfops, fsb, | |
1677 | rr->rr_rrec.rc_blockcount, NULL); | |
1678 | ||
5c33baee | 1679 | error = xfs_defer_finish(&tp, &dfops); |
10e65503 DW |
1680 | if (error) |
1681 | goto out_defer; | |
1682 | ||
1683 | error = xfs_trans_commit(tp); | |
1684 | if (error) | |
22a69322 | 1685 | goto out_free; |
d4e8eb2e DW |
1686 | |
1687 | list_del(&rr->rr_list); | |
1688 | kmem_free(rr); | |
10e65503 | 1689 | } |
10e65503 | 1690 | |
d4e8eb2e DW |
1691 | return error; |
1692 | out_defer: | |
1693 | xfs_defer_cancel(&dfops); | |
1694 | out_trans: | |
1695 | xfs_trans_cancel(tp); | |
10e65503 DW |
1696 | out_free: |
1697 | /* Free the leftover list */ | |
1698 | list_for_each_entry_safe(rr, n, &debris, rr_list) { | |
1699 | list_del(&rr->rr_list); | |
1700 | kmem_free(rr); | |
1701 | } | |
10e65503 DW |
1702 | return error; |
1703 | ||
22a69322 | 1704 | out_cursor: |
10e65503 | 1705 | xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); |
d4e8eb2e DW |
1706 | xfs_trans_brelse(tp, agbp); |
1707 | goto out_trans; | |
10e65503 | 1708 | } |
1048d0e2 DW |
1709 | |
1710 | /* Is there a record covering a given extent? */ | |
1711 | int | |
1712 | xfs_refcount_has_record( | |
1713 | struct xfs_btree_cur *cur, | |
1714 | xfs_agblock_t bno, | |
1715 | xfs_extlen_t len, | |
1716 | bool *exists) | |
1717 | { | |
1718 | union xfs_btree_irec low; | |
1719 | union xfs_btree_irec high; | |
1720 | ||
1721 | memset(&low, 0, sizeof(low)); | |
1722 | low.rc.rc_startblock = bno; | |
1723 | memset(&high, 0xFF, sizeof(high)); | |
1724 | high.rc.rc_startblock = bno + len - 1; | |
1725 | ||
1726 | return xfs_btree_has_record(cur, &low, &high, exists); | |
1727 | } |