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Merge tag 'xtensa-20180225' of git://github.com/jcmvbkbc/linux-xtensa
[cris-mirror.git] / fs / xfs / xfs_fsmap.c
blob43cfc07996a43ed1779e7ce6249df2113d87dc28
1 /*
2 * Copyright (C) 2017 Oracle. All Rights Reserved.
3 *
4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
10 *
11 * This program is distributed in the hope that it would be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
19 */
20 #include "xfs.h"
21 #include "xfs_fs.h"
22 #include "xfs_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_inode.h"
30 #include "xfs_trans.h"
31 #include "xfs_error.h"
32 #include "xfs_btree.h"
33 #include "xfs_rmap_btree.h"
34 #include "xfs_trace.h"
35 #include "xfs_log.h"
36 #include "xfs_rmap.h"
37 #include "xfs_alloc.h"
38 #include "xfs_bit.h"
39 #include <linux/fsmap.h>
40 #include "xfs_fsmap.h"
41 #include "xfs_refcount.h"
42 #include "xfs_refcount_btree.h"
43 #include "xfs_alloc_btree.h"
44 #include "xfs_rtalloc.h"
45
46 /* Convert an xfs_fsmap to an fsmap. */
47 void
48 xfs_fsmap_from_internal(
49 struct fsmap *dest,
50 struct xfs_fsmap *src)
51 {
52 dest->fmr_device = src->fmr_device;
53 dest->fmr_flags = src->fmr_flags;
54 dest->fmr_physical = BBTOB(src->fmr_physical);
55 dest->fmr_owner = src->fmr_owner;
56 dest->fmr_offset = BBTOB(src->fmr_offset);
57 dest->fmr_length = BBTOB(src->fmr_length);
58 dest->fmr_reserved[0] = 0;
59 dest->fmr_reserved[1] = 0;
60 dest->fmr_reserved[2] = 0;
61 }
62
63 /* Convert an fsmap to an xfs_fsmap. */
64 void
65 xfs_fsmap_to_internal(
66 struct xfs_fsmap *dest,
67 struct fsmap *src)
68 {
69 dest->fmr_device = src->fmr_device;
70 dest->fmr_flags = src->fmr_flags;
71 dest->fmr_physical = BTOBBT(src->fmr_physical);
72 dest->fmr_owner = src->fmr_owner;
73 dest->fmr_offset = BTOBBT(src->fmr_offset);
74 dest->fmr_length = BTOBBT(src->fmr_length);
75 }
76
77 /* Convert an fsmap owner into an rmapbt owner. */
78 static int
79 xfs_fsmap_owner_to_rmap(
80 struct xfs_rmap_irec *dest,
81 struct xfs_fsmap *src)
82 {
83 if (!(src->fmr_flags & FMR_OF_SPECIAL_OWNER)) {
84 dest->rm_owner = src->fmr_owner;
85 return 0;
86 }
87
88 switch (src->fmr_owner) {
89 case 0: /* "lowest owner id possible" */
90 case -1ULL: /* "highest owner id possible" */
91 dest->rm_owner = 0;
92 break;
93 case XFS_FMR_OWN_FREE:
94 dest->rm_owner = XFS_RMAP_OWN_NULL;
95 break;
96 case XFS_FMR_OWN_UNKNOWN:
97 dest->rm_owner = XFS_RMAP_OWN_UNKNOWN;
98 break;
99 case XFS_FMR_OWN_FS:
100 dest->rm_owner = XFS_RMAP_OWN_FS;
101 break;
102 case XFS_FMR_OWN_LOG:
103 dest->rm_owner = XFS_RMAP_OWN_LOG;
104 break;
105 case XFS_FMR_OWN_AG:
106 dest->rm_owner = XFS_RMAP_OWN_AG;
107 break;
108 case XFS_FMR_OWN_INOBT:
109 dest->rm_owner = XFS_RMAP_OWN_INOBT;
110 break;
111 case XFS_FMR_OWN_INODES:
112 dest->rm_owner = XFS_RMAP_OWN_INODES;
113 break;
114 case XFS_FMR_OWN_REFC:
115 dest->rm_owner = XFS_RMAP_OWN_REFC;
116 break;
117 case XFS_FMR_OWN_COW:
118 dest->rm_owner = XFS_RMAP_OWN_COW;
119 break;
120 case XFS_FMR_OWN_DEFECTIVE: /* not implemented */
121 /* fall through */
122 default:
123 return -EINVAL;
124 }
125 return 0;
126 }
127
128 /* Convert an rmapbt owner into an fsmap owner. */
129 static int
130 xfs_fsmap_owner_from_rmap(
131 struct xfs_fsmap *dest,
132 struct xfs_rmap_irec *src)
133 {
134 dest->fmr_flags = 0;
135 if (!XFS_RMAP_NON_INODE_OWNER(src->rm_owner)) {
136 dest->fmr_owner = src->rm_owner;
137 return 0;
138 }
139 dest->fmr_flags |= FMR_OF_SPECIAL_OWNER;
140
141 switch (src->rm_owner) {
142 case XFS_RMAP_OWN_FS:
143 dest->fmr_owner = XFS_FMR_OWN_FS;
144 break;
145 case XFS_RMAP_OWN_LOG:
146 dest->fmr_owner = XFS_FMR_OWN_LOG;
147 break;
148 case XFS_RMAP_OWN_AG:
149 dest->fmr_owner = XFS_FMR_OWN_AG;
150 break;
151 case XFS_RMAP_OWN_INOBT:
152 dest->fmr_owner = XFS_FMR_OWN_INOBT;
153 break;
154 case XFS_RMAP_OWN_INODES:
155 dest->fmr_owner = XFS_FMR_OWN_INODES;
156 break;
157 case XFS_RMAP_OWN_REFC:
158 dest->fmr_owner = XFS_FMR_OWN_REFC;
159 break;
160 case XFS_RMAP_OWN_COW:
161 dest->fmr_owner = XFS_FMR_OWN_COW;
162 break;
163 case XFS_RMAP_OWN_NULL: /* "free" */
164 dest->fmr_owner = XFS_FMR_OWN_FREE;
165 break;
166 default:
167 return -EFSCORRUPTED;
168 }
169 return 0;
170 }
171
172 /* getfsmap query state */
173 struct xfs_getfsmap_info {
174 struct xfs_fsmap_head *head;
175 xfs_fsmap_format_t formatter; /* formatting fn */
176 void *format_arg; /* format buffer */
177 struct xfs_buf *agf_bp; /* AGF, for refcount queries */
178 xfs_daddr_t next_daddr; /* next daddr we expect */
179 u64 missing_owner; /* owner of holes */
180 u32 dev; /* device id */
181 xfs_agnumber_t agno; /* AG number, if applicable */
182 struct xfs_rmap_irec low; /* low rmap key */
183 struct xfs_rmap_irec high; /* high rmap key */
184 bool last; /* last extent? */
185 };
186
187 /* Associate a device with a getfsmap handler. */
188 struct xfs_getfsmap_dev {
189 u32 dev;
190 int (*fn)(struct xfs_trans *tp,
191 struct xfs_fsmap *keys,
192 struct xfs_getfsmap_info *info);
193 };
194
195 /* Compare two getfsmap device handlers. */
196 static int
197 xfs_getfsmap_dev_compare(
198 const void *p1,
199 const void *p2)
200 {
201 const struct xfs_getfsmap_dev *d1 = p1;
202 const struct xfs_getfsmap_dev *d2 = p2;
203
204 return d1->dev - d2->dev;
205 }
206
207 /* Decide if this mapping is shared. */
208 STATIC int
209 xfs_getfsmap_is_shared(
210 struct xfs_trans *tp,
211 struct xfs_getfsmap_info *info,
212 struct xfs_rmap_irec *rec,
213 bool *stat)
214 {
215 struct xfs_mount *mp = tp->t_mountp;
216 struct xfs_btree_cur *cur;
217 xfs_agblock_t fbno;
218 xfs_extlen_t flen;
219 int error;
220
221 *stat = false;
222 if (!xfs_sb_version_hasreflink(&mp->m_sb))
223 return 0;
224 /* rt files will have agno set to NULLAGNUMBER */
225 if (info->agno == NULLAGNUMBER)
226 return 0;
227
228 /* Are there any shared blocks here? */
229 flen = 0;
230 cur = xfs_refcountbt_init_cursor(mp, tp, info->agf_bp,
231 info->agno, NULL);
232
233 error = xfs_refcount_find_shared(cur, rec->rm_startblock,
234 rec->rm_blockcount, &fbno, &flen, false);
235
236 xfs_btree_del_cursor(cur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
237 if (error)
238 return error;
239
240 *stat = flen > 0;
241 return 0;
242 }
243
244 /*
245 * Format a reverse mapping for getfsmap, having translated rm_startblock
246 * into the appropriate daddr units.
247 */
248 STATIC int
249 xfs_getfsmap_helper(
250 struct xfs_trans *tp,
251 struct xfs_getfsmap_info *info,
252 struct xfs_rmap_irec *rec,
253 xfs_daddr_t rec_daddr)
254 {
255 struct xfs_fsmap fmr;
256 struct xfs_mount *mp = tp->t_mountp;
257 bool shared;
258 int error;
259
260 if (fatal_signal_pending(current))
261 return -EINTR;
262
263 /*
264 * Filter out records that start before our startpoint, if the
265 * caller requested that.
266 */
267 if (xfs_rmap_compare(rec, &info->low) < 0) {
268 rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount);
269 if (info->next_daddr < rec_daddr)
270 info->next_daddr = rec_daddr;
271 return XFS_BTREE_QUERY_RANGE_CONTINUE;
272 }
273
274 /* Are we just counting mappings? */
275 if (info->head->fmh_count == 0) {
276 if (rec_daddr > info->next_daddr)
277 info->head->fmh_entries++;
278
279 if (info->last)
280 return XFS_BTREE_QUERY_RANGE_CONTINUE;
281
282 info->head->fmh_entries++;
283
284 rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount);
285 if (info->next_daddr < rec_daddr)
286 info->next_daddr = rec_daddr;
287 return XFS_BTREE_QUERY_RANGE_CONTINUE;
288 }
289
290 /*
291 * If the record starts past the last physical block we saw,
292 * then we've found a gap. Report the gap as being owned by
293 * whatever the caller specified is the missing owner.
294 */
295 if (rec_daddr > info->next_daddr) {
296 if (info->head->fmh_entries >= info->head->fmh_count)
297 return XFS_BTREE_QUERY_RANGE_ABORT;
298
299 fmr.fmr_device = info->dev;
300 fmr.fmr_physical = info->next_daddr;
301 fmr.fmr_owner = info->missing_owner;
302 fmr.fmr_offset = 0;
303 fmr.fmr_length = rec_daddr - info->next_daddr;
304 fmr.fmr_flags = FMR_OF_SPECIAL_OWNER;
305 error = info->formatter(&fmr, info->format_arg);
306 if (error)
307 return error;
308 info->head->fmh_entries++;
309 }
310
311 if (info->last)
312 goto out;
313
314 /* Fill out the extent we found */
315 if (info->head->fmh_entries >= info->head->fmh_count)
316 return XFS_BTREE_QUERY_RANGE_ABORT;
317
318 trace_xfs_fsmap_mapping(mp, info->dev, info->agno, rec);
319
320 fmr.fmr_device = info->dev;
321 fmr.fmr_physical = rec_daddr;
322 error = xfs_fsmap_owner_from_rmap(&fmr, rec);
323 if (error)
324 return error;
325 fmr.fmr_offset = XFS_FSB_TO_BB(mp, rec->rm_offset);
326 fmr.fmr_length = XFS_FSB_TO_BB(mp, rec->rm_blockcount);
327 if (rec->rm_flags & XFS_RMAP_UNWRITTEN)
328 fmr.fmr_flags |= FMR_OF_PREALLOC;
329 if (rec->rm_flags & XFS_RMAP_ATTR_FORK)
330 fmr.fmr_flags |= FMR_OF_ATTR_FORK;
331 if (rec->rm_flags & XFS_RMAP_BMBT_BLOCK)
332 fmr.fmr_flags |= FMR_OF_EXTENT_MAP;
333 if (fmr.fmr_flags == 0) {
334 error = xfs_getfsmap_is_shared(tp, info, rec, &shared);
335 if (error)
336 return error;
337 if (shared)
338 fmr.fmr_flags |= FMR_OF_SHARED;
339 }
340 error = info->formatter(&fmr, info->format_arg);
341 if (error)
342 return error;
343 info->head->fmh_entries++;
344
345 out:
346 rec_daddr += XFS_FSB_TO_BB(mp, rec->rm_blockcount);
347 if (info->next_daddr < rec_daddr)
348 info->next_daddr = rec_daddr;
349 return XFS_BTREE_QUERY_RANGE_CONTINUE;
350 }
351
352 /* Transform a rmapbt irec into a fsmap */
353 STATIC int
354 xfs_getfsmap_datadev_helper(
355 struct xfs_btree_cur *cur,
356 struct xfs_rmap_irec *rec,
357 void *priv)
358 {
359 struct xfs_mount *mp = cur->bc_mp;
360 struct xfs_getfsmap_info *info = priv;
361 xfs_fsblock_t fsb;
362 xfs_daddr_t rec_daddr;
363
364 fsb = XFS_AGB_TO_FSB(mp, cur->bc_private.a.agno, rec->rm_startblock);
365 rec_daddr = XFS_FSB_TO_DADDR(mp, fsb);
366
367 return xfs_getfsmap_helper(cur->bc_tp, info, rec, rec_daddr);
368 }
369
370 /* Transform a bnobt irec into a fsmap */
371 STATIC int
372 xfs_getfsmap_datadev_bnobt_helper(
373 struct xfs_btree_cur *cur,
374 struct xfs_alloc_rec_incore *rec,
375 void *priv)
376 {
377 struct xfs_mount *mp = cur->bc_mp;
378 struct xfs_getfsmap_info *info = priv;
379 struct xfs_rmap_irec irec;
380 xfs_daddr_t rec_daddr;
381
382 rec_daddr = XFS_AGB_TO_DADDR(mp, cur->bc_private.a.agno,
383 rec->ar_startblock);
384
385 irec.rm_startblock = rec->ar_startblock;
386 irec.rm_blockcount = rec->ar_blockcount;
387 irec.rm_owner = XFS_RMAP_OWN_NULL; /* "free" */
388 irec.rm_offset = 0;
389 irec.rm_flags = 0;
390
391 return xfs_getfsmap_helper(cur->bc_tp, info, &irec, rec_daddr);
392 }
393
394 /* Set rmap flags based on the getfsmap flags */
395 static void
396 xfs_getfsmap_set_irec_flags(
397 struct xfs_rmap_irec *irec,
398 struct xfs_fsmap *fmr)
399 {
400 irec->rm_flags = 0;
401 if (fmr->fmr_flags & FMR_OF_ATTR_FORK)
402 irec->rm_flags |= XFS_RMAP_ATTR_FORK;
403 if (fmr->fmr_flags & FMR_OF_EXTENT_MAP)
404 irec->rm_flags |= XFS_RMAP_BMBT_BLOCK;
405 if (fmr->fmr_flags & FMR_OF_PREALLOC)
406 irec->rm_flags |= XFS_RMAP_UNWRITTEN;
407 }
408
409 /* Execute a getfsmap query against the log device. */
410 STATIC int
411 xfs_getfsmap_logdev(
412 struct xfs_trans *tp,
413 struct xfs_fsmap *keys,
414 struct xfs_getfsmap_info *info)
415 {
416 struct xfs_mount *mp = tp->t_mountp;
417 struct xfs_rmap_irec rmap;
418 int error;
419
420 /* Set up search keys */
421 info->low.rm_startblock = XFS_BB_TO_FSBT(mp, keys[0].fmr_physical);
422 info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset);
423 error = xfs_fsmap_owner_to_rmap(&info->low, keys);
424 if (error)
425 return error;
426 info->low.rm_blockcount = 0;
427 xfs_getfsmap_set_irec_flags(&info->low, &keys[0]);
428
429 error = xfs_fsmap_owner_to_rmap(&info->high, keys + 1);
430 if (error)
431 return error;
432 info->high.rm_startblock = -1U;
433 info->high.rm_owner = ULLONG_MAX;
434 info->high.rm_offset = ULLONG_MAX;
435 info->high.rm_blockcount = 0;
436 info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS;
437 info->missing_owner = XFS_FMR_OWN_FREE;
438
439 trace_xfs_fsmap_low_key(mp, info->dev, info->agno, &info->low);
440 trace_xfs_fsmap_high_key(mp, info->dev, info->agno, &info->high);
441
442 if (keys[0].fmr_physical > 0)
443 return 0;
444
445 /* Fabricate an rmap entry for the external log device. */
446 rmap.rm_startblock = 0;
447 rmap.rm_blockcount = mp->m_sb.sb_logblocks;
448 rmap.rm_owner = XFS_RMAP_OWN_LOG;
449 rmap.rm_offset = 0;
450 rmap.rm_flags = 0;
451
452 return xfs_getfsmap_helper(tp, info, &rmap, 0);
453 }
454
455 #ifdef CONFIG_XFS_RT
456 /* Transform a rtbitmap "record" into a fsmap */
457 STATIC int
458 xfs_getfsmap_rtdev_rtbitmap_helper(
459 struct xfs_trans *tp,
460 struct xfs_rtalloc_rec *rec,
461 void *priv)
462 {
463 struct xfs_mount *mp = tp->t_mountp;
464 struct xfs_getfsmap_info *info = priv;
465 struct xfs_rmap_irec irec;
466 xfs_daddr_t rec_daddr;
467
468 rec_daddr = XFS_FSB_TO_BB(mp, rec->ar_startblock);
469
470 irec.rm_startblock = rec->ar_startblock;
471 irec.rm_blockcount = rec->ar_blockcount;
472 irec.rm_owner = XFS_RMAP_OWN_NULL; /* "free" */
473 irec.rm_offset = 0;
474 irec.rm_flags = 0;
475
476 return xfs_getfsmap_helper(tp, info, &irec, rec_daddr);
477 }
478
479 /* Execute a getfsmap query against the realtime device. */
480 STATIC int
481 __xfs_getfsmap_rtdev(
482 struct xfs_trans *tp,
483 struct xfs_fsmap *keys,
484 int (*query_fn)(struct xfs_trans *,
485 struct xfs_getfsmap_info *),
486 struct xfs_getfsmap_info *info)
487 {
488 struct xfs_mount *mp = tp->t_mountp;
489 xfs_fsblock_t start_fsb;
490 xfs_fsblock_t end_fsb;
491 xfs_daddr_t eofs;
492 int error = 0;
493
494 eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
495 if (keys[0].fmr_physical >= eofs)
496 return 0;
497 if (keys[1].fmr_physical >= eofs)
498 keys[1].fmr_physical = eofs - 1;
499 start_fsb = XFS_BB_TO_FSBT(mp, keys[0].fmr_physical);
500 end_fsb = XFS_BB_TO_FSB(mp, keys[1].fmr_physical);
501
502 /* Set up search keys */
503 info->low.rm_startblock = start_fsb;
504 error = xfs_fsmap_owner_to_rmap(&info->low, &keys[0]);
505 if (error)
506 return error;
507 info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset);
508 info->low.rm_blockcount = 0;
509 xfs_getfsmap_set_irec_flags(&info->low, &keys[0]);
510
511 info->high.rm_startblock = end_fsb;
512 error = xfs_fsmap_owner_to_rmap(&info->high, &keys[1]);
513 if (error)
514 return error;
515 info->high.rm_offset = XFS_BB_TO_FSBT(mp, keys[1].fmr_offset);
516 info->high.rm_blockcount = 0;
517 xfs_getfsmap_set_irec_flags(&info->high, &keys[1]);
518
519 trace_xfs_fsmap_low_key(mp, info->dev, info->agno, &info->low);
520 trace_xfs_fsmap_high_key(mp, info->dev, info->agno, &info->high);
521
522 return query_fn(tp, info);
523 }
524
525 /* Actually query the realtime bitmap. */
526 STATIC int
527 xfs_getfsmap_rtdev_rtbitmap_query(
528 struct xfs_trans *tp,
529 struct xfs_getfsmap_info *info)
530 {
531 struct xfs_rtalloc_rec alow;
532 struct xfs_rtalloc_rec ahigh;
533 int error;
534
535 xfs_ilock(tp->t_mountp->m_rbmip, XFS_ILOCK_SHARED);
536
537 alow.ar_startblock = info->low.rm_startblock;
538 ahigh.ar_startblock = info->high.rm_startblock;
539 error = xfs_rtalloc_query_range(tp, &alow, &ahigh,
540 xfs_getfsmap_rtdev_rtbitmap_helper, info);
541 if (error)
542 goto err;
543
544 /* Report any gaps at the end of the rtbitmap */
545 info->last = true;
546 error = xfs_getfsmap_rtdev_rtbitmap_helper(tp, &ahigh, info);
547 if (error)
548 goto err;
549 err:
550 xfs_iunlock(tp->t_mountp->m_rbmip, XFS_ILOCK_SHARED);
551 return error;
552 }
553
554 /* Execute a getfsmap query against the realtime device rtbitmap. */
555 STATIC int
556 xfs_getfsmap_rtdev_rtbitmap(
557 struct xfs_trans *tp,
558 struct xfs_fsmap *keys,
559 struct xfs_getfsmap_info *info)
560 {
561 info->missing_owner = XFS_FMR_OWN_UNKNOWN;
562 return __xfs_getfsmap_rtdev(tp, keys, xfs_getfsmap_rtdev_rtbitmap_query,
563 info);
564 }
565 #endif /* CONFIG_XFS_RT */
566
567 /* Execute a getfsmap query against the regular data device. */
568 STATIC int
569 __xfs_getfsmap_datadev(
570 struct xfs_trans *tp,
571 struct xfs_fsmap *keys,
572 struct xfs_getfsmap_info *info,
573 int (*query_fn)(struct xfs_trans *,
574 struct xfs_getfsmap_info *,
575 struct xfs_btree_cur **,
576 void *),
577 void *priv)
578 {
579 struct xfs_mount *mp = tp->t_mountp;
580 struct xfs_btree_cur *bt_cur = NULL;
581 xfs_fsblock_t start_fsb;
582 xfs_fsblock_t end_fsb;
583 xfs_agnumber_t start_ag;
584 xfs_agnumber_t end_ag;
585 xfs_daddr_t eofs;
586 int error = 0;
587
588 eofs = XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
589 if (keys[0].fmr_physical >= eofs)
590 return 0;
591 if (keys[1].fmr_physical >= eofs)
592 keys[1].fmr_physical = eofs - 1;
593 start_fsb = XFS_DADDR_TO_FSB(mp, keys[0].fmr_physical);
594 end_fsb = XFS_DADDR_TO_FSB(mp, keys[1].fmr_physical);
595
596 /*
597 * Convert the fsmap low/high keys to AG based keys. Initialize
598 * low to the fsmap low key and max out the high key to the end
599 * of the AG.
600 */
601 info->low.rm_startblock = XFS_FSB_TO_AGBNO(mp, start_fsb);
602 info->low.rm_offset = XFS_BB_TO_FSBT(mp, keys[0].fmr_offset);
603 error = xfs_fsmap_owner_to_rmap(&info->low, &keys[0]);
604 if (error)
605 return error;
606 info->low.rm_blockcount = 0;
607 xfs_getfsmap_set_irec_flags(&info->low, &keys[0]);
608
609 info->high.rm_startblock = -1U;
610 info->high.rm_owner = ULLONG_MAX;
611 info->high.rm_offset = ULLONG_MAX;
612 info->high.rm_blockcount = 0;
613 info->high.rm_flags = XFS_RMAP_KEY_FLAGS | XFS_RMAP_REC_FLAGS;
614
615 start_ag = XFS_FSB_TO_AGNO(mp, start_fsb);
616 end_ag = XFS_FSB_TO_AGNO(mp, end_fsb);
617
618 /* Query each AG */
619 for (info->agno = start_ag; info->agno <= end_ag; info->agno++) {
620 /*
621 * Set the AG high key from the fsmap high key if this
622 * is the last AG that we're querying.
623 */
624 if (info->agno == end_ag) {
625 info->high.rm_startblock = XFS_FSB_TO_AGBNO(mp,
626 end_fsb);
627 info->high.rm_offset = XFS_BB_TO_FSBT(mp,
628 keys[1].fmr_offset);
629 error = xfs_fsmap_owner_to_rmap(&info->high, &keys[1]);
630 if (error)
631 goto err;
632 xfs_getfsmap_set_irec_flags(&info->high, &keys[1]);
633 }
634
635 if (bt_cur) {
636 xfs_btree_del_cursor(bt_cur, XFS_BTREE_NOERROR);
637 bt_cur = NULL;
638 xfs_trans_brelse(tp, info->agf_bp);
639 info->agf_bp = NULL;
640 }
641
642 error = xfs_alloc_read_agf(mp, tp, info->agno, 0,
643 &info->agf_bp);
644 if (error)
645 goto err;
646
647 trace_xfs_fsmap_low_key(mp, info->dev, info->agno, &info->low);
648 trace_xfs_fsmap_high_key(mp, info->dev, info->agno,
649 &info->high);
650
651 error = query_fn(tp, info, &bt_cur, priv);
652 if (error)
653 goto err;
654
655 /*
656 * Set the AG low key to the start of the AG prior to
657 * moving on to the next AG.
658 */
659 if (info->agno == start_ag) {
660 info->low.rm_startblock = 0;
661 info->low.rm_owner = 0;
662 info->low.rm_offset = 0;
663 info->low.rm_flags = 0;
664 }
665 }
666
667 /* Report any gap at the end of the AG */
668 info->last = true;
669 error = query_fn(tp, info, &bt_cur, priv);
670 if (error)
671 goto err;
672
673 err:
674 if (bt_cur)
675 xfs_btree_del_cursor(bt_cur, error < 0 ? XFS_BTREE_ERROR :
676 XFS_BTREE_NOERROR);
677 if (info->agf_bp) {
678 xfs_trans_brelse(tp, info->agf_bp);
679 info->agf_bp = NULL;
680 }
681
682 return error;
683 }
684
685 /* Actually query the rmap btree. */
686 STATIC int
687 xfs_getfsmap_datadev_rmapbt_query(
688 struct xfs_trans *tp,
689 struct xfs_getfsmap_info *info,
690 struct xfs_btree_cur **curpp,
691 void *priv)
692 {
693 /* Report any gap at the end of the last AG. */
694 if (info->last)
695 return xfs_getfsmap_datadev_helper(*curpp, &info->high, info);
696
697 /* Allocate cursor for this AG and query_range it. */
698 *curpp = xfs_rmapbt_init_cursor(tp->t_mountp, tp, info->agf_bp,
699 info->agno);
700 return xfs_rmap_query_range(*curpp, &info->low, &info->high,
701 xfs_getfsmap_datadev_helper, info);
702 }
703
704 /* Execute a getfsmap query against the regular data device rmapbt. */
705 STATIC int
706 xfs_getfsmap_datadev_rmapbt(
707 struct xfs_trans *tp,
708 struct xfs_fsmap *keys,
709 struct xfs_getfsmap_info *info)
710 {
711 info->missing_owner = XFS_FMR_OWN_FREE;
712 return __xfs_getfsmap_datadev(tp, keys, info,
713 xfs_getfsmap_datadev_rmapbt_query, NULL);
714 }
715
716 /* Actually query the bno btree. */
717 STATIC int
718 xfs_getfsmap_datadev_bnobt_query(
719 struct xfs_trans *tp,
720 struct xfs_getfsmap_info *info,
721 struct xfs_btree_cur **curpp,
722 void *priv)
723 {
724 struct xfs_alloc_rec_incore *key = priv;
725
726 /* Report any gap at the end of the last AG. */
727 if (info->last)
728 return xfs_getfsmap_datadev_bnobt_helper(*curpp, &key[1], info);
729
730 /* Allocate cursor for this AG and query_range it. */
731 *curpp = xfs_allocbt_init_cursor(tp->t_mountp, tp, info->agf_bp,
732 info->agno, XFS_BTNUM_BNO);
733 key->ar_startblock = info->low.rm_startblock;
734 key[1].ar_startblock = info->high.rm_startblock;
735 return xfs_alloc_query_range(*curpp, key, &key[1],
736 xfs_getfsmap_datadev_bnobt_helper, info);
737 }
738
739 /* Execute a getfsmap query against the regular data device's bnobt. */
740 STATIC int
741 xfs_getfsmap_datadev_bnobt(
742 struct xfs_trans *tp,
743 struct xfs_fsmap *keys,
744 struct xfs_getfsmap_info *info)
745 {
746 struct xfs_alloc_rec_incore akeys[2];
747
748 info->missing_owner = XFS_FMR_OWN_UNKNOWN;
749 return __xfs_getfsmap_datadev(tp, keys, info,
750 xfs_getfsmap_datadev_bnobt_query, &akeys[0]);
751 }
752
753 /* Do we recognize the device? */
754 STATIC bool
755 xfs_getfsmap_is_valid_device(
756 struct xfs_mount *mp,
757 struct xfs_fsmap *fm)
758 {
759 if (fm->fmr_device == 0 || fm->fmr_device == UINT_MAX ||
760 fm->fmr_device == new_encode_dev(mp->m_ddev_targp->bt_dev))
761 return true;
762 if (mp->m_logdev_targp &&
763 fm->fmr_device == new_encode_dev(mp->m_logdev_targp->bt_dev))
764 return true;
765 if (mp->m_rtdev_targp &&
766 fm->fmr_device == new_encode_dev(mp->m_rtdev_targp->bt_dev))
767 return true;
768 return false;
769 }
770
771 /* Ensure that the low key is less than the high key. */
772 STATIC bool
773 xfs_getfsmap_check_keys(
774 struct xfs_fsmap *low_key,
775 struct xfs_fsmap *high_key)
776 {
777 if (low_key->fmr_device > high_key->fmr_device)
778 return false;
779 if (low_key->fmr_device < high_key->fmr_device)
780 return true;
781
782 if (low_key->fmr_physical > high_key->fmr_physical)
783 return false;
784 if (low_key->fmr_physical < high_key->fmr_physical)
785 return true;
786
787 if (low_key->fmr_owner > high_key->fmr_owner)
788 return false;
789 if (low_key->fmr_owner < high_key->fmr_owner)
790 return true;
791
792 if (low_key->fmr_offset > high_key->fmr_offset)
793 return false;
794 if (low_key->fmr_offset < high_key->fmr_offset)
795 return true;
796
797 return false;
798 }
799
800 /*
801 * There are only two devices if we didn't configure RT devices at build time.
802 */
803 #ifdef CONFIG_XFS_RT
804 #define XFS_GETFSMAP_DEVS 3
805 #else
806 #define XFS_GETFSMAP_DEVS 2
807 #endif /* CONFIG_XFS_RT */
808
809 /*
810 * Get filesystem's extents as described in head, and format for
811 * output. Calls formatter to fill the user's buffer until all
812 * extents are mapped, until the passed-in head->fmh_count slots have
813 * been filled, or until the formatter short-circuits the loop, if it
814 * is tracking filled-in extents on its own.
815 *
816 * Key to Confusion
817 * ----------------
818 * There are multiple levels of keys and counters at work here:
819 * xfs_fsmap_head.fmh_keys -- low and high fsmap keys passed in;
820 * these reflect fs-wide sector addrs.
821 * dkeys -- fmh_keys used to query each device;
822 * these are fmh_keys but w/ the low key
823 * bumped up by fmr_length.
824 * xfs_getfsmap_info.next_daddr -- next disk addr we expect to see; this
825 * is how we detect gaps in the fsmap
826 records and report them.
827 * xfs_getfsmap_info.low/high -- per-AG low/high keys computed from
828 * dkeys; used to query the metadata.
829 */
830 int
831 xfs_getfsmap(
832 struct xfs_mount *mp,
833 struct xfs_fsmap_head *head,
834 xfs_fsmap_format_t formatter,
835 void *arg)
836 {
837 struct xfs_trans *tp = NULL;
838 struct xfs_fsmap dkeys[2]; /* per-dev keys */
839 struct xfs_getfsmap_dev handlers[XFS_GETFSMAP_DEVS];
840 struct xfs_getfsmap_info info = { NULL };
841 bool use_rmap;
842 int i;
843 int error = 0;
844
845 if (head->fmh_iflags & ~FMH_IF_VALID)
846 return -EINVAL;
847 if (!xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[0]) ||
848 !xfs_getfsmap_is_valid_device(mp, &head->fmh_keys[1]))
849 return -EINVAL;
850
851 use_rmap = capable(CAP_SYS_ADMIN) &&
852 xfs_sb_version_hasrmapbt(&mp->m_sb);
853 head->fmh_entries = 0;
854
855 /* Set up our device handlers. */
856 memset(handlers, 0, sizeof(handlers));
857 handlers[0].dev = new_encode_dev(mp->m_ddev_targp->bt_dev);
858 if (use_rmap)
859 handlers[0].fn = xfs_getfsmap_datadev_rmapbt;
860 else
861 handlers[0].fn = xfs_getfsmap_datadev_bnobt;
862 if (mp->m_logdev_targp != mp->m_ddev_targp) {
863 handlers[1].dev = new_encode_dev(mp->m_logdev_targp->bt_dev);
864 handlers[1].fn = xfs_getfsmap_logdev;
865 }
866 #ifdef CONFIG_XFS_RT
867 if (mp->m_rtdev_targp) {
868 handlers[2].dev = new_encode_dev(mp->m_rtdev_targp->bt_dev);
869 handlers[2].fn = xfs_getfsmap_rtdev_rtbitmap;
870 }
871 #endif /* CONFIG_XFS_RT */
872
873 xfs_sort(handlers, XFS_GETFSMAP_DEVS, sizeof(struct xfs_getfsmap_dev),
874 xfs_getfsmap_dev_compare);
875
876 /*
877 * To continue where we left off, we allow userspace to use the
878 * last mapping from a previous call as the low key of the next.
879 * This is identified by a non-zero length in the low key. We
880 * have to increment the low key in this scenario to ensure we
881 * don't return the same mapping again, and instead return the
882 * very next mapping.
883 *
884 * If the low key mapping refers to file data, the same physical
885 * blocks could be mapped to several other files/offsets.
886 * According to rmapbt record ordering, the minimal next
887 * possible record for the block range is the next starting
888 * offset in the same inode. Therefore, bump the file offset to
889 * continue the search appropriately. For all other low key
890 * mapping types (attr blocks, metadata), bump the physical
891 * offset as there can be no other mapping for the same physical
892 * block range.
893 */
894 dkeys[0] = head->fmh_keys[0];
895 if (dkeys[0].fmr_flags & (FMR_OF_SPECIAL_OWNER | FMR_OF_EXTENT_MAP)) {
896 dkeys[0].fmr_physical += dkeys[0].fmr_length;
897 dkeys[0].fmr_owner = 0;
898 if (dkeys[0].fmr_offset)
899 return -EINVAL;
900 } else
901 dkeys[0].fmr_offset += dkeys[0].fmr_length;
902 dkeys[0].fmr_length = 0;
903 memset(&dkeys[1], 0xFF, sizeof(struct xfs_fsmap));
904
905 if (!xfs_getfsmap_check_keys(dkeys, &head->fmh_keys[1]))
906 return -EINVAL;
907
908 info.next_daddr = head->fmh_keys[0].fmr_physical +
909 head->fmh_keys[0].fmr_length;
910 info.formatter = formatter;
911 info.format_arg = arg;
912 info.head = head;
913
914 /* For each device we support... */
915 for (i = 0; i < XFS_GETFSMAP_DEVS; i++) {
916 /* Is this device within the range the user asked for? */
917 if (!handlers[i].fn)
918 continue;
919 if (head->fmh_keys[0].fmr_device > handlers[i].dev)
920 continue;
921 if (head->fmh_keys[1].fmr_device < handlers[i].dev)
922 break;
923
924 /*
925 * If this device number matches the high key, we have
926 * to pass the high key to the handler to limit the
927 * query results. If the device number exceeds the
928 * low key, zero out the low key so that we get
929 * everything from the beginning.
930 */
931 if (handlers[i].dev == head->fmh_keys[1].fmr_device)
932 dkeys[1] = head->fmh_keys[1];
933 if (handlers[i].dev > head->fmh_keys[0].fmr_device)
934 memset(&dkeys[0], 0, sizeof(struct xfs_fsmap));
935
936 error = xfs_trans_alloc_empty(mp, &tp);
937 if (error)
938 break;
939
940 info.dev = handlers[i].dev;
941 info.last = false;
942 info.agno = NULLAGNUMBER;
943 error = handlers[i].fn(tp, dkeys, &info);
944 if (error)
945 break;
946 xfs_trans_cancel(tp);
947 tp = NULL;
948 info.next_daddr = 0;
949 }
950
951 if (tp)
952 xfs_trans_cancel(tp);
953 head->fmh_oflags = FMH_OF_DEV_T;
954 return error;
955 }
CRIS linux kernel tree