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2b954308a1d671e9f09d06a5353713297f11be76
[GitHub/MotorolaMobilityLLC/kernel-slsi.git] / fs / xfs / xfs_bmap_util.c
1 /*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * Copyright (c) 2012 Red Hat, Inc.
4 * All Rights Reserved.
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 as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19 #include "xfs.h"
20 #include "xfs_fs.h"
21 #include "xfs_shared.h"
22 #include "xfs_format.h"
23 #include "xfs_log_format.h"
24 #include "xfs_trans_resv.h"
25 #include "xfs_bit.h"
26 #include "xfs_mount.h"
27 #include "xfs_da_format.h"
28 #include "xfs_defer.h"
29 #include "xfs_inode.h"
30 #include "xfs_btree.h"
31 #include "xfs_trans.h"
32 #include "xfs_extfree_item.h"
33 #include "xfs_alloc.h"
34 #include "xfs_bmap.h"
35 #include "xfs_bmap_util.h"
36 #include "xfs_bmap_btree.h"
37 #include "xfs_rtalloc.h"
38 #include "xfs_error.h"
39 #include "xfs_quota.h"
40 #include "xfs_trans_space.h"
41 #include "xfs_trace.h"
42 #include "xfs_icache.h"
43 #include "xfs_log.h"
44 #include "xfs_rmap_btree.h"
45 #include "xfs_iomap.h"
46 #include "xfs_reflink.h"
47 #include "xfs_refcount.h"
48
49 /* Kernel only BMAP related definitions and functions */
50
51 /*
52 * Convert the given file system block to a disk block. We have to treat it
53 * differently based on whether the file is a real time file or not, because the
54 * bmap code does.
55 */
56 xfs_daddr_t
57 xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
58 {
59 return (XFS_IS_REALTIME_INODE(ip) ? \
60 (xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \
61 XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
62 }
63
64 /*
65 * Routine to zero an extent on disk allocated to the specific inode.
66 *
67 * The VFS functions take a linearised filesystem block offset, so we have to
68 * convert the sparse xfs fsb to the right format first.
69 * VFS types are real funky, too.
70 */
71 int
72 xfs_zero_extent(
73 struct xfs_inode *ip,
74 xfs_fsblock_t start_fsb,
75 xfs_off_t count_fsb)
76 {
77 struct xfs_mount *mp = ip->i_mount;
78 xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb);
79 sector_t block = XFS_BB_TO_FSBT(mp, sector);
80
81 return blkdev_issue_zeroout(xfs_find_bdev_for_inode(VFS_I(ip)),
82 block << (mp->m_super->s_blocksize_bits - 9),
83 count_fsb << (mp->m_super->s_blocksize_bits - 9),
84 GFP_NOFS, 0);
85 }
86
87 int
88 xfs_bmap_rtalloc(
89 struct xfs_bmalloca *ap) /* bmap alloc argument struct */
90 {
91 int error; /* error return value */
92 xfs_mount_t *mp; /* mount point structure */
93 xfs_extlen_t prod = 0; /* product factor for allocators */
94 xfs_extlen_t ralen = 0; /* realtime allocation length */
95 xfs_extlen_t align; /* minimum allocation alignment */
96 xfs_rtblock_t rtb;
97
98 mp = ap->ip->i_mount;
99 align = xfs_get_extsz_hint(ap->ip);
100 prod = align / mp->m_sb.sb_rextsize;
101 error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
102 align, 1, ap->eof, 0,
103 ap->conv, &ap->offset, &ap->length);
104 if (error)
105 return error;
106 ASSERT(ap->length);
107 ASSERT(ap->length % mp->m_sb.sb_rextsize == 0);
108
109 /*
110 * If the offset & length are not perfectly aligned
111 * then kill prod, it will just get us in trouble.
112 */
113 if (do_mod(ap->offset, align) || ap->length % align)
114 prod = 1;
115 /*
116 * Set ralen to be the actual requested length in rtextents.
117 */
118 ralen = ap->length / mp->m_sb.sb_rextsize;
119 /*
120 * If the old value was close enough to MAXEXTLEN that
121 * we rounded up to it, cut it back so it's valid again.
122 * Note that if it's a really large request (bigger than
123 * MAXEXTLEN), we don't hear about that number, and can't
124 * adjust the starting point to match it.
125 */
126 if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN)
127 ralen = MAXEXTLEN / mp->m_sb.sb_rextsize;
128
129 /*
130 * Lock out modifications to both the RT bitmap and summary inodes
131 */
132 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
133 xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL);
134 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
135 xfs_trans_ijoin(ap->tp, mp->m_rsumip, XFS_ILOCK_EXCL);
136
137 /*
138 * If it's an allocation to an empty file at offset 0,
139 * pick an extent that will space things out in the rt area.
140 */
141 if (ap->eof && ap->offset == 0) {
142 xfs_rtblock_t uninitialized_var(rtx); /* realtime extent no */
143
144 error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx);
145 if (error)
146 return error;
147 ap->blkno = rtx * mp->m_sb.sb_rextsize;
148 } else {
149 ap->blkno = 0;
150 }
151
152 xfs_bmap_adjacent(ap);
153
154 /*
155 * Realtime allocation, done through xfs_rtallocate_extent.
156 */
157 do_div(ap->blkno, mp->m_sb.sb_rextsize);
158 rtb = ap->blkno;
159 ap->length = ralen;
160 error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, ap->length,
161 &ralen, ap->wasdel, prod, &rtb);
162 if (error)
163 return error;
164
165 ap->blkno = rtb;
166 if (ap->blkno != NULLFSBLOCK) {
167 ap->blkno *= mp->m_sb.sb_rextsize;
168 ralen *= mp->m_sb.sb_rextsize;
169 ap->length = ralen;
170 ap->ip->i_d.di_nblocks += ralen;
171 xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
172 if (ap->wasdel)
173 ap->ip->i_delayed_blks -= ralen;
174 /*
175 * Adjust the disk quota also. This was reserved
176 * earlier.
177 */
178 xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
179 ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
180 XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
181
182 /* Zero the extent if we were asked to do so */
183 if (ap->datatype & XFS_ALLOC_USERDATA_ZERO) {
184 error = xfs_zero_extent(ap->ip, ap->blkno, ap->length);
185 if (error)
186 return error;
187 }
188 } else {
189 ap->length = 0;
190 }
191 return 0;
192 }
193
194 /*
195 * Check if the endoff is outside the last extent. If so the caller will grow
196 * the allocation to a stripe unit boundary. All offsets are considered outside
197 * the end of file for an empty fork, so 1 is returned in *eof in that case.
198 */
199 int
200 xfs_bmap_eof(
201 struct xfs_inode *ip,
202 xfs_fileoff_t endoff,
203 int whichfork,
204 int *eof)
205 {
206 struct xfs_bmbt_irec rec;
207 int error;
208
209 error = xfs_bmap_last_extent(NULL, ip, whichfork, &rec, eof);
210 if (error || *eof)
211 return error;
212
213 *eof = endoff >= rec.br_startoff + rec.br_blockcount;
214 return 0;
215 }
216
217 /*
218 * Extent tree block counting routines.
219 */
220
221 /*
222 * Count leaf blocks given a range of extent records.
223 */
224 STATIC void
225 xfs_bmap_count_leaves(
226 xfs_ifork_t *ifp,
227 xfs_extnum_t idx,
228 int numrecs,
229 int *count)
230 {
231 int b;
232
233 for (b = 0; b < numrecs; b++) {
234 xfs_bmbt_rec_host_t *frp = xfs_iext_get_ext(ifp, idx + b);
235 *count += xfs_bmbt_get_blockcount(frp);
236 }
237 }
238
239 /*
240 * Count leaf blocks given a range of extent records originally
241 * in btree format.
242 */
243 STATIC void
244 xfs_bmap_disk_count_leaves(
245 struct xfs_mount *mp,
246 struct xfs_btree_block *block,
247 int numrecs,
248 int *count)
249 {
250 int b;
251 xfs_bmbt_rec_t *frp;
252
253 for (b = 1; b <= numrecs; b++) {
254 frp = XFS_BMBT_REC_ADDR(mp, block, b);
255 *count += xfs_bmbt_disk_get_blockcount(frp);
256 }
257 }
258
259 /*
260 * Recursively walks each level of a btree
261 * to count total fsblocks in use.
262 */
263 STATIC int /* error */
264 xfs_bmap_count_tree(
265 xfs_mount_t *mp, /* file system mount point */
266 xfs_trans_t *tp, /* transaction pointer */
267 xfs_ifork_t *ifp, /* inode fork pointer */
268 xfs_fsblock_t blockno, /* file system block number */
269 int levelin, /* level in btree */
270 int *count) /* Count of blocks */
271 {
272 int error;
273 xfs_buf_t *bp, *nbp;
274 int level = levelin;
275 __be64 *pp;
276 xfs_fsblock_t bno = blockno;
277 xfs_fsblock_t nextbno;
278 struct xfs_btree_block *block, *nextblock;
279 int numrecs;
280
281 error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp, XFS_BMAP_BTREE_REF,
282 &xfs_bmbt_buf_ops);
283 if (error)
284 return error;
285 *count += 1;
286 block = XFS_BUF_TO_BLOCK(bp);
287
288 if (--level) {
289 /* Not at node above leaves, count this level of nodes */
290 nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
291 while (nextbno != NULLFSBLOCK) {
292 error = xfs_btree_read_bufl(mp, tp, nextbno, 0, &nbp,
293 XFS_BMAP_BTREE_REF,
294 &xfs_bmbt_buf_ops);
295 if (error)
296 return error;
297 *count += 1;
298 nextblock = XFS_BUF_TO_BLOCK(nbp);
299 nextbno = be64_to_cpu(nextblock->bb_u.l.bb_rightsib);
300 xfs_trans_brelse(tp, nbp);
301 }
302
303 /* Dive to the next level */
304 pp = XFS_BMBT_PTR_ADDR(mp, block, 1, mp->m_bmap_dmxr[1]);
305 bno = be64_to_cpu(*pp);
306 if (unlikely((error =
307 xfs_bmap_count_tree(mp, tp, ifp, bno, level, count)) < 0)) {
308 xfs_trans_brelse(tp, bp);
309 XFS_ERROR_REPORT("xfs_bmap_count_tree(1)",
310 XFS_ERRLEVEL_LOW, mp);
311 return -EFSCORRUPTED;
312 }
313 xfs_trans_brelse(tp, bp);
314 } else {
315 /* count all level 1 nodes and their leaves */
316 for (;;) {
317 nextbno = be64_to_cpu(block->bb_u.l.bb_rightsib);
318 numrecs = be16_to_cpu(block->bb_numrecs);
319 xfs_bmap_disk_count_leaves(mp, block, numrecs, count);
320 xfs_trans_brelse(tp, bp);
321 if (nextbno == NULLFSBLOCK)
322 break;
323 bno = nextbno;
324 error = xfs_btree_read_bufl(mp, tp, bno, 0, &bp,
325 XFS_BMAP_BTREE_REF,
326 &xfs_bmbt_buf_ops);
327 if (error)
328 return error;
329 *count += 1;
330 block = XFS_BUF_TO_BLOCK(bp);
331 }
332 }
333 return 0;
334 }
335
336 /*
337 * Count fsblocks of the given fork.
338 */
339 static int /* error */
340 xfs_bmap_count_blocks(
341 xfs_trans_t *tp, /* transaction pointer */
342 xfs_inode_t *ip, /* incore inode */
343 int whichfork, /* data or attr fork */
344 int *count) /* out: count of blocks */
345 {
346 struct xfs_btree_block *block; /* current btree block */
347 xfs_fsblock_t bno; /* block # of "block" */
348 xfs_ifork_t *ifp; /* fork structure */
349 int level; /* btree level, for checking */
350 xfs_mount_t *mp; /* file system mount structure */
351 __be64 *pp; /* pointer to block address */
352
353 bno = NULLFSBLOCK;
354 mp = ip->i_mount;
355 ifp = XFS_IFORK_PTR(ip, whichfork);
356 if ( XFS_IFORK_FORMAT(ip, whichfork) == XFS_DINODE_FMT_EXTENTS ) {
357 xfs_bmap_count_leaves(ifp, 0, xfs_iext_count(ifp), count);
358 return 0;
359 }
360
361 /*
362 * Root level must use BMAP_BROOT_PTR_ADDR macro to get ptr out.
363 */
364 block = ifp->if_broot;
365 level = be16_to_cpu(block->bb_level);
366 ASSERT(level > 0);
367 pp = XFS_BMAP_BROOT_PTR_ADDR(mp, block, 1, ifp->if_broot_bytes);
368 bno = be64_to_cpu(*pp);
369 ASSERT(bno != NULLFSBLOCK);
370 ASSERT(XFS_FSB_TO_AGNO(mp, bno) < mp->m_sb.sb_agcount);
371 ASSERT(XFS_FSB_TO_AGBNO(mp, bno) < mp->m_sb.sb_agblocks);
372
373 if (unlikely(xfs_bmap_count_tree(mp, tp, ifp, bno, level, count) < 0)) {
374 XFS_ERROR_REPORT("xfs_bmap_count_blocks(2)", XFS_ERRLEVEL_LOW,
375 mp);
376 return -EFSCORRUPTED;
377 }
378
379 return 0;
380 }
381
382 /*
383 * returns 1 for success, 0 if we failed to map the extent.
384 */
385 STATIC int
386 xfs_getbmapx_fix_eof_hole(
387 xfs_inode_t *ip, /* xfs incore inode pointer */
388 int whichfork,
389 struct getbmapx *out, /* output structure */
390 int prealloced, /* this is a file with
391 * preallocated data space */
392 __int64_t end, /* last block requested */
393 xfs_fsblock_t startblock,
394 bool moretocome)
395 {
396 __int64_t fixlen;
397 xfs_mount_t *mp; /* file system mount point */
398 xfs_ifork_t *ifp; /* inode fork pointer */
399 xfs_extnum_t lastx; /* last extent pointer */
400 xfs_fileoff_t fileblock;
401
402 if (startblock == HOLESTARTBLOCK) {
403 mp = ip->i_mount;
404 out->bmv_block = -1;
405 fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
406 fixlen -= out->bmv_offset;
407 if (prealloced && out->bmv_offset + out->bmv_length == end) {
408 /* Came to hole at EOF. Trim it. */
409 if (fixlen <= 0)
410 return 0;
411 out->bmv_length = fixlen;
412 }
413 } else {
414 if (startblock == DELAYSTARTBLOCK)
415 out->bmv_block = -2;
416 else
417 out->bmv_block = xfs_fsb_to_db(ip, startblock);
418 fileblock = XFS_BB_TO_FSB(ip->i_mount, out->bmv_offset);
419 ifp = XFS_IFORK_PTR(ip, whichfork);
420 if (!moretocome &&
421 xfs_iext_bno_to_ext(ifp, fileblock, &lastx) &&
422 (lastx == xfs_iext_count(ifp) - 1))
423 out->bmv_oflags |= BMV_OF_LAST;
424 }
425
426 return 1;
427 }
428
429 /* Adjust the reported bmap around shared/unshared extent transitions. */
430 STATIC int
431 xfs_getbmap_adjust_shared(
432 struct xfs_inode *ip,
433 int whichfork,
434 struct xfs_bmbt_irec *map,
435 struct getbmapx *out,
436 struct xfs_bmbt_irec *next_map)
437 {
438 struct xfs_mount *mp = ip->i_mount;
439 xfs_agnumber_t agno;
440 xfs_agblock_t agbno;
441 xfs_agblock_t ebno;
442 xfs_extlen_t elen;
443 xfs_extlen_t nlen;
444 int error;
445
446 next_map->br_startblock = NULLFSBLOCK;
447 next_map->br_startoff = NULLFILEOFF;
448 next_map->br_blockcount = 0;
449
450 /* Only written data blocks can be shared. */
451 if (!xfs_is_reflink_inode(ip) ||
452 whichfork != XFS_DATA_FORK ||
453 !xfs_bmap_is_real_extent(map))
454 return 0;
455
456 agno = XFS_FSB_TO_AGNO(mp, map->br_startblock);
457 agbno = XFS_FSB_TO_AGBNO(mp, map->br_startblock);
458 error = xfs_reflink_find_shared(mp, agno, agbno, map->br_blockcount,
459 &ebno, &elen, true);
460 if (error)
461 return error;
462
463 if (ebno == NULLAGBLOCK) {
464 /* No shared blocks at all. */
465 return 0;
466 } else if (agbno == ebno) {
467 /*
468 * Shared extent at (agbno, elen). Shrink the reported
469 * extent length and prepare to move the start of map[i]
470 * to agbno+elen, with the aim of (re)formatting the new
471 * map[i] the next time through the inner loop.
472 */
473 out->bmv_length = XFS_FSB_TO_BB(mp, elen);
474 out->bmv_oflags |= BMV_OF_SHARED;
475 if (elen != map->br_blockcount) {
476 *next_map = *map;
477 next_map->br_startblock += elen;
478 next_map->br_startoff += elen;
479 next_map->br_blockcount -= elen;
480 }
481 map->br_blockcount -= elen;
482 } else {
483 /*
484 * There's an unshared extent (agbno, ebno - agbno)
485 * followed by shared extent at (ebno, elen). Shrink
486 * the reported extent length to cover only the unshared
487 * extent and prepare to move up the start of map[i] to
488 * ebno, with the aim of (re)formatting the new map[i]
489 * the next time through the inner loop.
490 */
491 *next_map = *map;
492 nlen = ebno - agbno;
493 out->bmv_length = XFS_FSB_TO_BB(mp, nlen);
494 next_map->br_startblock += nlen;
495 next_map->br_startoff += nlen;
496 next_map->br_blockcount -= nlen;
497 map->br_blockcount -= nlen;
498 }
499
500 return 0;
501 }
502
503 /*
504 * Get inode's extents as described in bmv, and format for output.
505 * Calls formatter to fill the user's buffer until all extents
506 * are mapped, until the passed-in bmv->bmv_count slots have
507 * been filled, or until the formatter short-circuits the loop,
508 * if it is tracking filled-in extents on its own.
509 */
510 int /* error code */
511 xfs_getbmap(
512 xfs_inode_t *ip,
513 struct getbmapx *bmv, /* user bmap structure */
514 xfs_bmap_format_t formatter, /* format to user */
515 void *arg) /* formatter arg */
516 {
517 __int64_t bmvend; /* last block requested */
518 int error = 0; /* return value */
519 __int64_t fixlen; /* length for -1 case */
520 int i; /* extent number */
521 int lock; /* lock state */
522 xfs_bmbt_irec_t *map; /* buffer for user's data */
523 xfs_mount_t *mp; /* file system mount point */
524 int nex; /* # of user extents can do */
525 int subnex; /* # of bmapi's can do */
526 int nmap; /* number of map entries */
527 struct getbmapx *out; /* output structure */
528 int whichfork; /* data or attr fork */
529 int prealloced; /* this is a file with
530 * preallocated data space */
531 int iflags; /* interface flags */
532 int bmapi_flags; /* flags for xfs_bmapi */
533 int cur_ext = 0;
534 struct xfs_bmbt_irec inject_map;
535
536 mp = ip->i_mount;
537 iflags = bmv->bmv_iflags;
538
539 #ifndef DEBUG
540 /* Only allow CoW fork queries if we're debugging. */
541 if (iflags & BMV_IF_COWFORK)
542 return -EINVAL;
543 #endif
544 if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK))
545 return -EINVAL;
546
547 if (iflags & BMV_IF_ATTRFORK)
548 whichfork = XFS_ATTR_FORK;
549 else if (iflags & BMV_IF_COWFORK)
550 whichfork = XFS_COW_FORK;
551 else
552 whichfork = XFS_DATA_FORK;
553
554 switch (whichfork) {
555 case XFS_ATTR_FORK:
556 if (XFS_IFORK_Q(ip)) {
557 if (ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS &&
558 ip->i_d.di_aformat != XFS_DINODE_FMT_BTREE &&
559 ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)
560 return -EINVAL;
561 } else if (unlikely(
562 ip->i_d.di_aformat != 0 &&
563 ip->i_d.di_aformat != XFS_DINODE_FMT_EXTENTS)) {
564 XFS_ERROR_REPORT("xfs_getbmap", XFS_ERRLEVEL_LOW,
565 ip->i_mount);
566 return -EFSCORRUPTED;
567 }
568
569 prealloced = 0;
570 fixlen = 1LL << 32;
571 break;
572 case XFS_COW_FORK:
573 if (ip->i_cformat != XFS_DINODE_FMT_EXTENTS)
574 return -EINVAL;
575
576 if (xfs_get_cowextsz_hint(ip)) {
577 prealloced = 1;
578 fixlen = mp->m_super->s_maxbytes;
579 } else {
580 prealloced = 0;
581 fixlen = XFS_ISIZE(ip);
582 }
583 break;
584 default:
585 if (ip->i_d.di_format != XFS_DINODE_FMT_EXTENTS &&
586 ip->i_d.di_format != XFS_DINODE_FMT_BTREE &&
587 ip->i_d.di_format != XFS_DINODE_FMT_LOCAL)
588 return -EINVAL;
589
590 if (xfs_get_extsz_hint(ip) ||
591 ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC|XFS_DIFLAG_APPEND)){
592 prealloced = 1;
593 fixlen = mp->m_super->s_maxbytes;
594 } else {
595 prealloced = 0;
596 fixlen = XFS_ISIZE(ip);
597 }
598 break;
599 }
600
601 if (bmv->bmv_length == -1) {
602 fixlen = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, fixlen));
603 bmv->bmv_length =
604 max_t(__int64_t, fixlen - bmv->bmv_offset, 0);
605 } else if (bmv->bmv_length == 0) {
606 bmv->bmv_entries = 0;
607 return 0;
608 } else if (bmv->bmv_length < 0) {
609 return -EINVAL;
610 }
611
612 nex = bmv->bmv_count - 1;
613 if (nex <= 0)
614 return -EINVAL;
615 bmvend = bmv->bmv_offset + bmv->bmv_length;
616
617
618 if (bmv->bmv_count > ULONG_MAX / sizeof(struct getbmapx))
619 return -ENOMEM;
620 out = kmem_zalloc_large(bmv->bmv_count * sizeof(struct getbmapx), 0);
621 if (!out)
622 return -ENOMEM;
623
624 xfs_ilock(ip, XFS_IOLOCK_SHARED);
625 switch (whichfork) {
626 case XFS_DATA_FORK:
627 if (!(iflags & BMV_IF_DELALLOC) &&
628 (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) {
629 error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
630 if (error)
631 goto out_unlock_iolock;
632
633 /*
634 * Even after flushing the inode, there can still be
635 * delalloc blocks on the inode beyond EOF due to
636 * speculative preallocation. These are not removed
637 * until the release function is called or the inode
638 * is inactivated. Hence we cannot assert here that
639 * ip->i_delayed_blks == 0.
640 */
641 }
642
643 lock = xfs_ilock_data_map_shared(ip);
644 break;
645 case XFS_COW_FORK:
646 lock = XFS_ILOCK_SHARED;
647 xfs_ilock(ip, lock);
648 break;
649 case XFS_ATTR_FORK:
650 lock = xfs_ilock_attr_map_shared(ip);
651 break;
652 }
653
654 /*
655 * Don't let nex be bigger than the number of extents
656 * we can have assuming alternating holes and real extents.
657 */
658 if (nex > XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1)
659 nex = XFS_IFORK_NEXTENTS(ip, whichfork) * 2 + 1;
660
661 bmapi_flags = xfs_bmapi_aflag(whichfork);
662 if (!(iflags & BMV_IF_PREALLOC))
663 bmapi_flags |= XFS_BMAPI_IGSTATE;
664
665 /*
666 * Allocate enough space to handle "subnex" maps at a time.
667 */
668 error = -ENOMEM;
669 subnex = 16;
670 map = kmem_alloc(subnex * sizeof(*map), KM_MAYFAIL | KM_NOFS);
671 if (!map)
672 goto out_unlock_ilock;
673
674 bmv->bmv_entries = 0;
675
676 if (XFS_IFORK_NEXTENTS(ip, whichfork) == 0 &&
677 (whichfork == XFS_ATTR_FORK || !(iflags & BMV_IF_DELALLOC))) {
678 error = 0;
679 goto out_free_map;
680 }
681
682 do {
683 nmap = (nex> subnex) ? subnex : nex;
684 error = xfs_bmapi_read(ip, XFS_BB_TO_FSBT(mp, bmv->bmv_offset),
685 XFS_BB_TO_FSB(mp, bmv->bmv_length),
686 map, &nmap, bmapi_flags);
687 if (error)
688 goto out_free_map;
689 ASSERT(nmap <= subnex);
690
691 for (i = 0; i < nmap && bmv->bmv_length &&
692 cur_ext < bmv->bmv_count - 1; i++) {
693 out[cur_ext].bmv_oflags = 0;
694 if (map[i].br_state == XFS_EXT_UNWRITTEN)
695 out[cur_ext].bmv_oflags |= BMV_OF_PREALLOC;
696 else if (map[i].br_startblock == DELAYSTARTBLOCK)
697 out[cur_ext].bmv_oflags |= BMV_OF_DELALLOC;
698 out[cur_ext].bmv_offset =
699 XFS_FSB_TO_BB(mp, map[i].br_startoff);
700 out[cur_ext].bmv_length =
701 XFS_FSB_TO_BB(mp, map[i].br_blockcount);
702 out[cur_ext].bmv_unused1 = 0;
703 out[cur_ext].bmv_unused2 = 0;
704
705 /*
706 * delayed allocation extents that start beyond EOF can
707 * occur due to speculative EOF allocation when the
708 * delalloc extent is larger than the largest freespace
709 * extent at conversion time. These extents cannot be
710 * converted by data writeback, so can exist here even
711 * if we are not supposed to be finding delalloc
712 * extents.
713 */
714 if (map[i].br_startblock == DELAYSTARTBLOCK &&
715 map[i].br_startoff <= XFS_B_TO_FSB(mp, XFS_ISIZE(ip)))
716 ASSERT((iflags & BMV_IF_DELALLOC) != 0);
717
718 if (map[i].br_startblock == HOLESTARTBLOCK &&
719 whichfork == XFS_ATTR_FORK) {
720 /* came to the end of attribute fork */
721 out[cur_ext].bmv_oflags |= BMV_OF_LAST;
722 goto out_free_map;
723 }
724
725 /* Is this a shared block? */
726 error = xfs_getbmap_adjust_shared(ip, whichfork,
727 &map[i], &out[cur_ext], &inject_map);
728 if (error)
729 goto out_free_map;
730
731 if (!xfs_getbmapx_fix_eof_hole(ip, whichfork,
732 &out[cur_ext], prealloced, bmvend,
733 map[i].br_startblock,
734 inject_map.br_startblock != NULLFSBLOCK))
735 goto out_free_map;
736
737 bmv->bmv_offset =
738 out[cur_ext].bmv_offset +
739 out[cur_ext].bmv_length;
740 bmv->bmv_length =
741 max_t(__int64_t, 0, bmvend - bmv->bmv_offset);
742
743 /*
744 * In case we don't want to return the hole,
745 * don't increase cur_ext so that we can reuse
746 * it in the next loop.
747 */
748 if ((iflags & BMV_IF_NO_HOLES) &&
749 map[i].br_startblock == HOLESTARTBLOCK) {
750 memset(&out[cur_ext], 0, sizeof(out[cur_ext]));
751 continue;
752 }
753
754 /*
755 * In order to report shared extents accurately,
756 * we report each distinct shared/unshared part
757 * of a single bmbt record using multiple bmap
758 * extents. To make that happen, we iterate the
759 * same map array item multiple times, each
760 * time trimming out the subextent that we just
761 * reported.
762 *
763 * Because of this, we must check the out array
764 * index (cur_ext) directly against bmv_count-1
765 * to avoid overflows.
766 */
767 if (inject_map.br_startblock != NULLFSBLOCK) {
768 map[i] = inject_map;
769 i--;
770 }
771 bmv->bmv_entries++;
772 cur_ext++;
773 }
774 } while (nmap && bmv->bmv_length && cur_ext < bmv->bmv_count - 1);
775
776 out_free_map:
777 kmem_free(map);
778 out_unlock_ilock:
779 xfs_iunlock(ip, lock);
780 out_unlock_iolock:
781 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
782
783 for (i = 0; i < cur_ext; i++) {
784 /* format results & advance arg */
785 error = formatter(&arg, &out[i]);
786 if (error)
787 break;
788 }
789
790 kmem_free(out);
791 return error;
792 }
793
794 /*
795 * dead simple method of punching delalyed allocation blocks from a range in
796 * the inode. Walks a block at a time so will be slow, but is only executed in
797 * rare error cases so the overhead is not critical. This will always punch out
798 * both the start and end blocks, even if the ranges only partially overlap
799 * them, so it is up to the caller to ensure that partial blocks are not
800 * passed in.
801 */
802 int
803 xfs_bmap_punch_delalloc_range(
804 struct xfs_inode *ip,
805 xfs_fileoff_t start_fsb,
806 xfs_fileoff_t length)
807 {
808 xfs_fileoff_t remaining = length;
809 int error = 0;
810
811 ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
812
813 do {
814 int done;
815 xfs_bmbt_irec_t imap;
816 int nimaps = 1;
817 xfs_fsblock_t firstblock;
818 struct xfs_defer_ops dfops;
819
820 /*
821 * Map the range first and check that it is a delalloc extent
822 * before trying to unmap the range. Otherwise we will be
823 * trying to remove a real extent (which requires a
824 * transaction) or a hole, which is probably a bad idea...
825 */
826 error = xfs_bmapi_read(ip, start_fsb, 1, &imap, &nimaps,
827 XFS_BMAPI_ENTIRE);
828
829 if (error) {
830 /* something screwed, just bail */
831 if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
832 xfs_alert(ip->i_mount,
833 "Failed delalloc mapping lookup ino %lld fsb %lld.",
834 ip->i_ino, start_fsb);
835 }
836 break;
837 }
838 if (!nimaps) {
839 /* nothing there */
840 goto next_block;
841 }
842 if (imap.br_startblock != DELAYSTARTBLOCK) {
843 /* been converted, ignore */
844 goto next_block;
845 }
846 WARN_ON(imap.br_blockcount == 0);
847
848 /*
849 * Note: while we initialise the firstblock/dfops pair, they
850 * should never be used because blocks should never be
851 * allocated or freed for a delalloc extent and hence we need
852 * don't cancel or finish them after the xfs_bunmapi() call.
853 */
854 xfs_defer_init(&dfops, &firstblock);
855 error = xfs_bunmapi(NULL, ip, start_fsb, 1, 0, 1, &firstblock,
856 &dfops, &done);
857 if (error)
858 break;
859
860 ASSERT(!xfs_defer_has_unfinished_work(&dfops));
861 next_block:
862 start_fsb++;
863 remaining--;
864 } while(remaining > 0);
865
866 return error;
867 }
868
869 /*
870 * Test whether it is appropriate to check an inode for and free post EOF
871 * blocks. The 'force' parameter determines whether we should also consider
872 * regular files that are marked preallocated or append-only.
873 */
874 bool
875 xfs_can_free_eofblocks(struct xfs_inode *ip, bool force)
876 {
877 /* prealloc/delalloc exists only on regular files */
878 if (!S_ISREG(VFS_I(ip)->i_mode))
879 return false;
880
881 /*
882 * Zero sized files with no cached pages and delalloc blocks will not
883 * have speculative prealloc/delalloc blocks to remove.
884 */
885 if (VFS_I(ip)->i_size == 0 &&
886 VFS_I(ip)->i_mapping->nrpages == 0 &&
887 ip->i_delayed_blks == 0)
888 return false;
889
890 /* If we haven't read in the extent list, then don't do it now. */
891 if (!(ip->i_df.if_flags & XFS_IFEXTENTS))
892 return false;
893
894 /*
895 * Do not free real preallocated or append-only files unless the file
896 * has delalloc blocks and we are forced to remove them.
897 */
898 if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))
899 if (!force || ip->i_delayed_blks == 0)
900 return false;
901
902 return true;
903 }
904
905 /*
906 * This is called to free any blocks beyond eof. The caller must hold
907 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only
908 * reference to the inode.
909 */
910 int
911 xfs_free_eofblocks(
912 struct xfs_inode *ip)
913 {
914 struct xfs_trans *tp;
915 int error;
916 xfs_fileoff_t end_fsb;
917 xfs_fileoff_t last_fsb;
918 xfs_filblks_t map_len;
919 int nimaps;
920 struct xfs_bmbt_irec imap;
921 struct xfs_mount *mp = ip->i_mount;
922
923 /*
924 * Figure out if there are any blocks beyond the end
925 * of the file. If not, then there is nothing to do.
926 */
927 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
928 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
929 if (last_fsb <= end_fsb)
930 return 0;
931 map_len = last_fsb - end_fsb;
932
933 nimaps = 1;
934 xfs_ilock(ip, XFS_ILOCK_SHARED);
935 error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
936 xfs_iunlock(ip, XFS_ILOCK_SHARED);
937
938 /*
939 * If there are blocks after the end of file, truncate the file to its
940 * current size to free them up.
941 */
942 if (!error && (nimaps != 0) &&
943 (imap.br_startblock != HOLESTARTBLOCK ||
944 ip->i_delayed_blks)) {
945 /*
946 * Attach the dquots to the inode up front.
947 */
948 error = xfs_qm_dqattach(ip, 0);
949 if (error)
950 return error;
951
952 /* wait on dio to ensure i_size has settled */
953 inode_dio_wait(VFS_I(ip));
954
955 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0,
956 &tp);
957 if (error) {
958 ASSERT(XFS_FORCED_SHUTDOWN(mp));
959 return error;
960 }
961
962 xfs_ilock(ip, XFS_ILOCK_EXCL);
963 xfs_trans_ijoin(tp, ip, 0);
964
965 /*
966 * Do not update the on-disk file size. If we update the
967 * on-disk file size and then the system crashes before the
968 * contents of the file are flushed to disk then the files
969 * may be full of holes (ie NULL files bug).
970 */
971 error = xfs_itruncate_extents(&tp, ip, XFS_DATA_FORK,
972 XFS_ISIZE(ip));
973 if (error) {
974 /*
975 * If we get an error at this point we simply don't
976 * bother truncating the file.
977 */
978 xfs_trans_cancel(tp);
979 } else {
980 error = xfs_trans_commit(tp);
981 if (!error)
982 xfs_inode_clear_eofblocks_tag(ip);
983 }
984
985 xfs_iunlock(ip, XFS_ILOCK_EXCL);
986 }
987 return error;
988 }
989
990 int
991 xfs_alloc_file_space(
992 struct xfs_inode *ip,
993 xfs_off_t offset,
994 xfs_off_t len,
995 int alloc_type)
996 {
997 xfs_mount_t *mp = ip->i_mount;
998 xfs_off_t count;
999 xfs_filblks_t allocated_fsb;
1000 xfs_filblks_t allocatesize_fsb;
1001 xfs_extlen_t extsz, temp;
1002 xfs_fileoff_t startoffset_fsb;
1003 xfs_fsblock_t firstfsb;
1004 int nimaps;
1005 int quota_flag;
1006 int rt;
1007 xfs_trans_t *tp;
1008 xfs_bmbt_irec_t imaps[1], *imapp;
1009 struct xfs_defer_ops dfops;
1010 uint qblocks, resblks, resrtextents;
1011 int error;
1012
1013 trace_xfs_alloc_file_space(ip);
1014
1015 if (XFS_FORCED_SHUTDOWN(mp))
1016 return -EIO;
1017
1018 error = xfs_qm_dqattach(ip, 0);
1019 if (error)
1020 return error;
1021
1022 if (len <= 0)
1023 return -EINVAL;
1024
1025 rt = XFS_IS_REALTIME_INODE(ip);
1026 extsz = xfs_get_extsz_hint(ip);
1027
1028 count = len;
1029 imapp = &imaps[0];
1030 nimaps = 1;
1031 startoffset_fsb = XFS_B_TO_FSBT(mp, offset);
1032 allocatesize_fsb = XFS_B_TO_FSB(mp, count);
1033
1034 /*
1035 * Allocate file space until done or until there is an error
1036 */
1037 while (allocatesize_fsb && !error) {
1038 xfs_fileoff_t s, e;
1039
1040 /*
1041 * Determine space reservations for data/realtime.
1042 */
1043 if (unlikely(extsz)) {
1044 s = startoffset_fsb;
1045 do_div(s, extsz);
1046 s *= extsz;
1047 e = startoffset_fsb + allocatesize_fsb;
1048 if ((temp = do_mod(startoffset_fsb, extsz)))
1049 e += temp;
1050 if ((temp = do_mod(e, extsz)))
1051 e += extsz - temp;
1052 } else {
1053 s = 0;
1054 e = allocatesize_fsb;
1055 }
1056
1057 /*
1058 * The transaction reservation is limited to a 32-bit block
1059 * count, hence we need to limit the number of blocks we are
1060 * trying to reserve to avoid an overflow. We can't allocate
1061 * more than @nimaps extents, and an extent is limited on disk
1062 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
1063 */
1064 resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
1065 if (unlikely(rt)) {
1066 resrtextents = qblocks = resblks;
1067 resrtextents /= mp->m_sb.sb_rextsize;
1068 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1069 quota_flag = XFS_QMOPT_RES_RTBLKS;
1070 } else {
1071 resrtextents = 0;
1072 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
1073 quota_flag = XFS_QMOPT_RES_REGBLKS;
1074 }
1075
1076 /*
1077 * Allocate and setup the transaction.
1078 */
1079 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
1080 resrtextents, 0, &tp);
1081
1082 /*
1083 * Check for running out of space
1084 */
1085 if (error) {
1086 /*
1087 * Free the transaction structure.
1088 */
1089 ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1090 break;
1091 }
1092 xfs_ilock(ip, XFS_ILOCK_EXCL);
1093 error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
1094 0, quota_flag);
1095 if (error)
1096 goto error1;
1097
1098 xfs_trans_ijoin(tp, ip, 0);
1099
1100 xfs_defer_init(&dfops, &firstfsb);
1101 error = xfs_bmapi_write(tp, ip, startoffset_fsb,
1102 allocatesize_fsb, alloc_type, &firstfsb,
1103 resblks, imapp, &nimaps, &dfops);
1104 if (error)
1105 goto error0;
1106
1107 /*
1108 * Complete the transaction
1109 */
1110 error = xfs_defer_finish(&tp, &dfops, NULL);
1111 if (error)
1112 goto error0;
1113
1114 error = xfs_trans_commit(tp);
1115 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1116 if (error)
1117 break;
1118
1119 allocated_fsb = imapp->br_blockcount;
1120
1121 if (nimaps == 0) {
1122 error = -ENOSPC;
1123 break;
1124 }
1125
1126 startoffset_fsb += allocated_fsb;
1127 allocatesize_fsb -= allocated_fsb;
1128 }
1129
1130 return error;
1131
1132 error0: /* Cancel bmap, unlock inode, unreserve quota blocks, cancel trans */
1133 xfs_defer_cancel(&dfops);
1134 xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag);
1135
1136 error1: /* Just cancel transaction */
1137 xfs_trans_cancel(tp);
1138 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1139 return error;
1140 }
1141
1142 static int
1143 xfs_unmap_extent(
1144 struct xfs_inode *ip,
1145 xfs_fileoff_t startoffset_fsb,
1146 xfs_filblks_t len_fsb,
1147 int *done)
1148 {
1149 struct xfs_mount *mp = ip->i_mount;
1150 struct xfs_trans *tp;
1151 struct xfs_defer_ops dfops;
1152 xfs_fsblock_t firstfsb;
1153 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1154 int error;
1155
1156 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
1157 if (error) {
1158 ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
1159 return error;
1160 }
1161
1162 xfs_ilock(ip, XFS_ILOCK_EXCL);
1163 error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot, ip->i_gdquot,
1164 ip->i_pdquot, resblks, 0, XFS_QMOPT_RES_REGBLKS);
1165 if (error)
1166 goto out_trans_cancel;
1167
1168 xfs_trans_ijoin(tp, ip, 0);
1169
1170 xfs_defer_init(&dfops, &firstfsb);
1171 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, &firstfsb,
1172 &dfops, done);
1173 if (error)
1174 goto out_bmap_cancel;
1175
1176 error = xfs_defer_finish(&tp, &dfops, ip);
1177 if (error)
1178 goto out_bmap_cancel;
1179
1180 error = xfs_trans_commit(tp);
1181 out_unlock:
1182 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1183 return error;
1184
1185 out_bmap_cancel:
1186 xfs_defer_cancel(&dfops);
1187 out_trans_cancel:
1188 xfs_trans_cancel(tp);
1189 goto out_unlock;
1190 }
1191
1192 static int
1193 xfs_adjust_extent_unmap_boundaries(
1194 struct xfs_inode *ip,
1195 xfs_fileoff_t *startoffset_fsb,
1196 xfs_fileoff_t *endoffset_fsb)
1197 {
1198 struct xfs_mount *mp = ip->i_mount;
1199 struct xfs_bmbt_irec imap;
1200 int nimap, error;
1201 xfs_extlen_t mod = 0;
1202
1203 nimap = 1;
1204 error = xfs_bmapi_read(ip, *startoffset_fsb, 1, &imap, &nimap, 0);
1205 if (error)
1206 return error;
1207
1208 if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1209 ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1210 mod = do_mod(imap.br_startblock, mp->m_sb.sb_rextsize);
1211 if (mod)
1212 *startoffset_fsb += mp->m_sb.sb_rextsize - mod;
1213 }
1214
1215 nimap = 1;
1216 error = xfs_bmapi_read(ip, *endoffset_fsb - 1, 1, &imap, &nimap, 0);
1217 if (error)
1218 return error;
1219
1220 if (nimap && imap.br_startblock != HOLESTARTBLOCK) {
1221 ASSERT(imap.br_startblock != DELAYSTARTBLOCK);
1222 mod++;
1223 if (mod && mod != mp->m_sb.sb_rextsize)
1224 *endoffset_fsb -= mod;
1225 }
1226
1227 return 0;
1228 }
1229
1230 static int
1231 xfs_flush_unmap_range(
1232 struct xfs_inode *ip,
1233 xfs_off_t offset,
1234 xfs_off_t len)
1235 {
1236 struct xfs_mount *mp = ip->i_mount;
1237 struct inode *inode = VFS_I(ip);
1238 xfs_off_t rounding, start, end;
1239 int error;
1240
1241 /* wait for the completion of any pending DIOs */
1242 inode_dio_wait(inode);
1243
1244 rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_SIZE);
1245 start = round_down(offset, rounding);
1246 end = round_up(offset + len, rounding) - 1;
1247
1248 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
1249 if (error)
1250 return error;
1251 truncate_pagecache_range(inode, start, end);
1252 return 0;
1253 }
1254
1255 int
1256 xfs_free_file_space(
1257 struct xfs_inode *ip,
1258 xfs_off_t offset,
1259 xfs_off_t len)
1260 {
1261 struct xfs_mount *mp = ip->i_mount;
1262 xfs_fileoff_t startoffset_fsb;
1263 xfs_fileoff_t endoffset_fsb;
1264 int done = 0, error;
1265
1266 trace_xfs_free_file_space(ip);
1267
1268 error = xfs_qm_dqattach(ip, 0);
1269 if (error)
1270 return error;
1271
1272 if (len <= 0) /* if nothing being freed */
1273 return 0;
1274
1275 error = xfs_flush_unmap_range(ip, offset, len);
1276 if (error)
1277 return error;
1278
1279 startoffset_fsb = XFS_B_TO_FSB(mp, offset);
1280 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
1281
1282 /*
1283 * Need to zero the stuff we're not freeing, on disk. If it's a RT file
1284 * and we can't use unwritten extents then we actually need to ensure
1285 * to zero the whole extent, otherwise we just need to take of block
1286 * boundaries, and xfs_bunmapi will handle the rest.
1287 */
1288 if (XFS_IS_REALTIME_INODE(ip) &&
1289 !xfs_sb_version_hasextflgbit(&mp->m_sb)) {
1290 error = xfs_adjust_extent_unmap_boundaries(ip, &startoffset_fsb,
1291 &endoffset_fsb);
1292 if (error)
1293 return error;
1294 }
1295
1296 if (endoffset_fsb > startoffset_fsb) {
1297 while (!done) {
1298 error = xfs_unmap_extent(ip, startoffset_fsb,
1299 endoffset_fsb - startoffset_fsb, &done);
1300 if (error)
1301 return error;
1302 }
1303 }
1304
1305 /*
1306 * Now that we've unmap all full blocks we'll have to zero out any
1307 * partial block at the beginning and/or end. xfs_zero_range is
1308 * smart enough to skip any holes, including those we just created,
1309 * but we must take care not to zero beyond EOF and enlarge i_size.
1310 */
1311
1312 if (offset >= XFS_ISIZE(ip))
1313 return 0;
1314
1315 if (offset + len > XFS_ISIZE(ip))
1316 len = XFS_ISIZE(ip) - offset;
1317
1318 return xfs_zero_range(ip, offset, len, NULL);
1319 }
1320
1321 /*
1322 * Preallocate and zero a range of a file. This mechanism has the allocation
1323 * semantics of fallocate and in addition converts data in the range to zeroes.
1324 */
1325 int
1326 xfs_zero_file_space(
1327 struct xfs_inode *ip,
1328 xfs_off_t offset,
1329 xfs_off_t len)
1330 {
1331 struct xfs_mount *mp = ip->i_mount;
1332 uint blksize;
1333 int error;
1334
1335 trace_xfs_zero_file_space(ip);
1336
1337 blksize = 1 << mp->m_sb.sb_blocklog;
1338
1339 /*
1340 * Punch a hole and prealloc the range. We use hole punch rather than
1341 * unwritten extent conversion for two reasons:
1342 *
1343 * 1.) Hole punch handles partial block zeroing for us.
1344 *
1345 * 2.) If prealloc returns ENOSPC, the file range is still zero-valued
1346 * by virtue of the hole punch.
1347 */
1348 error = xfs_free_file_space(ip, offset, len);
1349 if (error)
1350 goto out;
1351
1352 error = xfs_alloc_file_space(ip, round_down(offset, blksize),
1353 round_up(offset + len, blksize) -
1354 round_down(offset, blksize),
1355 XFS_BMAPI_PREALLOC);
1356 out:
1357 return error;
1358
1359 }
1360
1361 /*
1362 * @next_fsb will keep track of the extent currently undergoing shift.
1363 * @stop_fsb will keep track of the extent at which we have to stop.
1364 * If we are shifting left, we will start with block (offset + len) and
1365 * shift each extent till last extent.
1366 * If we are shifting right, we will start with last extent inside file space
1367 * and continue until we reach the block corresponding to offset.
1368 */
1369 static int
1370 xfs_shift_file_space(
1371 struct xfs_inode *ip,
1372 xfs_off_t offset,
1373 xfs_off_t len,
1374 enum shift_direction direction)
1375 {
1376 int done = 0;
1377 struct xfs_mount *mp = ip->i_mount;
1378 struct xfs_trans *tp;
1379 int error;
1380 struct xfs_defer_ops dfops;
1381 xfs_fsblock_t first_block;
1382 xfs_fileoff_t stop_fsb;
1383 xfs_fileoff_t next_fsb;
1384 xfs_fileoff_t shift_fsb;
1385 uint resblks;
1386
1387 ASSERT(direction == SHIFT_LEFT || direction == SHIFT_RIGHT);
1388
1389 if (direction == SHIFT_LEFT) {
1390 /*
1391 * Reserve blocks to cover potential extent merges after left
1392 * shift operations.
1393 */
1394 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
1395 next_fsb = XFS_B_TO_FSB(mp, offset + len);
1396 stop_fsb = XFS_B_TO_FSB(mp, VFS_I(ip)->i_size);
1397 } else {
1398 /*
1399 * If right shift, delegate the work of initialization of
1400 * next_fsb to xfs_bmap_shift_extent as it has ilock held.
1401 */
1402 resblks = 0;
1403 next_fsb = NULLFSBLOCK;
1404 stop_fsb = XFS_B_TO_FSB(mp, offset);
1405 }
1406
1407 shift_fsb = XFS_B_TO_FSB(mp, len);
1408
1409 /*
1410 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation
1411 * into the accessible region of the file.
1412 */
1413 if (xfs_can_free_eofblocks(ip, true)) {
1414 error = xfs_free_eofblocks(ip);
1415 if (error)
1416 return error;
1417 }
1418
1419 /*
1420 * Writeback and invalidate cache for the remainder of the file as we're
1421 * about to shift down every extent from offset to EOF.
1422 */
1423 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
1424 offset, -1);
1425 if (error)
1426 return error;
1427 error = invalidate_inode_pages2_range(VFS_I(ip)->i_mapping,
1428 offset >> PAGE_SHIFT, -1);
1429 if (error)
1430 return error;
1431
1432 /*
1433 * The extent shiting code works on extent granularity. So, if
1434 * stop_fsb is not the starting block of extent, we need to split
1435 * the extent at stop_fsb.
1436 */
1437 if (direction == SHIFT_RIGHT) {
1438 error = xfs_bmap_split_extent(ip, stop_fsb);
1439 if (error)
1440 return error;
1441 }
1442
1443 while (!error && !done) {
1444 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0,
1445 &tp);
1446 if (error)
1447 break;
1448
1449 xfs_ilock(ip, XFS_ILOCK_EXCL);
1450 error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot,
1451 ip->i_gdquot, ip->i_pdquot, resblks, 0,
1452 XFS_QMOPT_RES_REGBLKS);
1453 if (error)
1454 goto out_trans_cancel;
1455
1456 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
1457
1458 xfs_defer_init(&dfops, &first_block);
1459
1460 /*
1461 * We are using the write transaction in which max 2 bmbt
1462 * updates are allowed
1463 */
1464 error = xfs_bmap_shift_extents(tp, ip, &next_fsb, shift_fsb,
1465 &done, stop_fsb, &first_block, &dfops,
1466 direction, XFS_BMAP_MAX_SHIFT_EXTENTS);
1467 if (error)
1468 goto out_bmap_cancel;
1469
1470 error = xfs_defer_finish(&tp, &dfops, NULL);
1471 if (error)
1472 goto out_bmap_cancel;
1473
1474 error = xfs_trans_commit(tp);
1475 }
1476
1477 return error;
1478
1479 out_bmap_cancel:
1480 xfs_defer_cancel(&dfops);
1481 out_trans_cancel:
1482 xfs_trans_cancel(tp);
1483 return error;
1484 }
1485
1486 /*
1487 * xfs_collapse_file_space()
1488 * This routine frees disk space and shift extent for the given file.
1489 * The first thing we do is to free data blocks in the specified range
1490 * by calling xfs_free_file_space(). It would also sync dirty data
1491 * and invalidate page cache over the region on which collapse range
1492 * is working. And Shift extent records to the left to cover a hole.
1493 * RETURNS:
1494 * 0 on success
1495 * errno on error
1496 *
1497 */
1498 int
1499 xfs_collapse_file_space(
1500 struct xfs_inode *ip,
1501 xfs_off_t offset,
1502 xfs_off_t len)
1503 {
1504 int error;
1505
1506 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1507 trace_xfs_collapse_file_space(ip);
1508
1509 error = xfs_free_file_space(ip, offset, len);
1510 if (error)
1511 return error;
1512
1513 return xfs_shift_file_space(ip, offset, len, SHIFT_LEFT);
1514 }
1515
1516 /*
1517 * xfs_insert_file_space()
1518 * This routine create hole space by shifting extents for the given file.
1519 * The first thing we do is to sync dirty data and invalidate page cache
1520 * over the region on which insert range is working. And split an extent
1521 * to two extents at given offset by calling xfs_bmap_split_extent.
1522 * And shift all extent records which are laying between [offset,
1523 * last allocated extent] to the right to reserve hole range.
1524 * RETURNS:
1525 * 0 on success
1526 * errno on error
1527 */
1528 int
1529 xfs_insert_file_space(
1530 struct xfs_inode *ip,
1531 loff_t offset,
1532 loff_t len)
1533 {
1534 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1535 trace_xfs_insert_file_space(ip);
1536
1537 return xfs_shift_file_space(ip, offset, len, SHIFT_RIGHT);
1538 }
1539
1540 /*
1541 * We need to check that the format of the data fork in the temporary inode is
1542 * valid for the target inode before doing the swap. This is not a problem with
1543 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
1544 * data fork depending on the space the attribute fork is taking so we can get
1545 * invalid formats on the target inode.
1546 *
1547 * E.g. target has space for 7 extents in extent format, temp inode only has
1548 * space for 6. If we defragment down to 7 extents, then the tmp format is a
1549 * btree, but when swapped it needs to be in extent format. Hence we can't just
1550 * blindly swap data forks on attr2 filesystems.
1551 *
1552 * Note that we check the swap in both directions so that we don't end up with
1553 * a corrupt temporary inode, either.
1554 *
1555 * Note that fixing the way xfs_fsr sets up the attribute fork in the source
1556 * inode will prevent this situation from occurring, so all we do here is
1557 * reject and log the attempt. basically we are putting the responsibility on
1558 * userspace to get this right.
1559 */
1560 static int
1561 xfs_swap_extents_check_format(
1562 struct xfs_inode *ip, /* target inode */
1563 struct xfs_inode *tip) /* tmp inode */
1564 {
1565
1566 /* Should never get a local format */
1567 if (ip->i_d.di_format == XFS_DINODE_FMT_LOCAL ||
1568 tip->i_d.di_format == XFS_DINODE_FMT_LOCAL)
1569 return -EINVAL;
1570
1571 /*
1572 * if the target inode has less extents that then temporary inode then
1573 * why did userspace call us?
1574 */
1575 if (ip->i_d.di_nextents < tip->i_d.di_nextents)
1576 return -EINVAL;
1577
1578 /*
1579 * If we have to use the (expensive) rmap swap method, we can
1580 * handle any number of extents and any format.
1581 */
1582 if (xfs_sb_version_hasrmapbt(&ip->i_mount->m_sb))
1583 return 0;
1584
1585 /*
1586 * if the target inode is in extent form and the temp inode is in btree
1587 * form then we will end up with the target inode in the wrong format
1588 * as we already know there are less extents in the temp inode.
1589 */
1590 if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1591 tip->i_d.di_format == XFS_DINODE_FMT_BTREE)
1592 return -EINVAL;
1593
1594 /* Check temp in extent form to max in target */
1595 if (tip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1596 XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) >
1597 XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1598 return -EINVAL;
1599
1600 /* Check target in extent form to max in temp */
1601 if (ip->i_d.di_format == XFS_DINODE_FMT_EXTENTS &&
1602 XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) >
1603 XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1604 return -EINVAL;
1605
1606 /*
1607 * If we are in a btree format, check that the temp root block will fit
1608 * in the target and that it has enough extents to be in btree format
1609 * in the target.
1610 *
1611 * Note that we have to be careful to allow btree->extent conversions
1612 * (a common defrag case) which will occur when the temp inode is in
1613 * extent format...
1614 */
1615 if (tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1616 if (XFS_IFORK_BOFF(ip) &&
1617 XFS_BMAP_BMDR_SPACE(tip->i_df.if_broot) > XFS_IFORK_BOFF(ip))
1618 return -EINVAL;
1619 if (XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK) <=
1620 XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1621 return -EINVAL;
1622 }
1623
1624 /* Reciprocal target->temp btree format checks */
1625 if (ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1626 if (XFS_IFORK_BOFF(tip) &&
1627 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip))
1628 return -EINVAL;
1629 if (XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK) <=
1630 XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1631 return -EINVAL;
1632 }
1633
1634 return 0;
1635 }
1636
1637 static int
1638 xfs_swap_extent_flush(
1639 struct xfs_inode *ip)
1640 {
1641 int error;
1642
1643 error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
1644 if (error)
1645 return error;
1646 truncate_pagecache_range(VFS_I(ip), 0, -1);
1647
1648 /* Verify O_DIRECT for ftmp */
1649 if (VFS_I(ip)->i_mapping->nrpages)
1650 return -EINVAL;
1651 return 0;
1652 }
1653
1654 /*
1655 * Move extents from one file to another, when rmap is enabled.
1656 */
1657 STATIC int
1658 xfs_swap_extent_rmap(
1659 struct xfs_trans **tpp,
1660 struct xfs_inode *ip,
1661 struct xfs_inode *tip)
1662 {
1663 struct xfs_bmbt_irec irec;
1664 struct xfs_bmbt_irec uirec;
1665 struct xfs_bmbt_irec tirec;
1666 xfs_fileoff_t offset_fsb;
1667 xfs_fileoff_t end_fsb;
1668 xfs_filblks_t count_fsb;
1669 xfs_fsblock_t firstfsb;
1670 struct xfs_defer_ops dfops;
1671 int error;
1672 xfs_filblks_t ilen;
1673 xfs_filblks_t rlen;
1674 int nimaps;
1675 __uint64_t tip_flags2;
1676
1677 /*
1678 * If the source file has shared blocks, we must flag the donor
1679 * file as having shared blocks so that we get the shared-block
1680 * rmap functions when we go to fix up the rmaps. The flags
1681 * will be switch for reals later.
1682 */
1683 tip_flags2 = tip->i_d.di_flags2;
1684 if (ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)
1685 tip->i_d.di_flags2 |= XFS_DIFLAG2_REFLINK;
1686
1687 offset_fsb = 0;
1688 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip)));
1689 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
1690
1691 while (count_fsb) {
1692 /* Read extent from the donor file */
1693 nimaps = 1;
1694 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec,
1695 &nimaps, 0);
1696 if (error)
1697 goto out;
1698 ASSERT(nimaps == 1);
1699 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK);
1700
1701 trace_xfs_swap_extent_rmap_remap(tip, &tirec);
1702 ilen = tirec.br_blockcount;
1703
1704 /* Unmap the old blocks in the source file. */
1705 while (tirec.br_blockcount) {
1706 xfs_defer_init(&dfops, &firstfsb);
1707 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec);
1708
1709 /* Read extent from the source file */
1710 nimaps = 1;
1711 error = xfs_bmapi_read(ip, tirec.br_startoff,
1712 tirec.br_blockcount, &irec,
1713 &nimaps, 0);
1714 if (error)
1715 goto out_defer;
1716 ASSERT(nimaps == 1);
1717 ASSERT(tirec.br_startoff == irec.br_startoff);
1718 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec);
1719
1720 /* Trim the extent. */
1721 uirec = tirec;
1722 uirec.br_blockcount = rlen = min_t(xfs_filblks_t,
1723 tirec.br_blockcount,
1724 irec.br_blockcount);
1725 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec);
1726
1727 /* Remove the mapping from the donor file. */
1728 error = xfs_bmap_unmap_extent((*tpp)->t_mountp, &dfops,
1729 tip, &uirec);
1730 if (error)
1731 goto out_defer;
1732
1733 /* Remove the mapping from the source file. */
1734 error = xfs_bmap_unmap_extent((*tpp)->t_mountp, &dfops,
1735 ip, &irec);
1736 if (error)
1737 goto out_defer;
1738
1739 /* Map the donor file's blocks into the source file. */
1740 error = xfs_bmap_map_extent((*tpp)->t_mountp, &dfops,
1741 ip, &uirec);
1742 if (error)
1743 goto out_defer;
1744
1745 /* Map the source file's blocks into the donor file. */
1746 error = xfs_bmap_map_extent((*tpp)->t_mountp, &dfops,
1747 tip, &irec);
1748 if (error)
1749 goto out_defer;
1750
1751 error = xfs_defer_finish(tpp, &dfops, ip);
1752 if (error)
1753 goto out_defer;
1754
1755 tirec.br_startoff += rlen;
1756 if (tirec.br_startblock != HOLESTARTBLOCK &&
1757 tirec.br_startblock != DELAYSTARTBLOCK)
1758 tirec.br_startblock += rlen;
1759 tirec.br_blockcount -= rlen;
1760 }
1761
1762 /* Roll on... */
1763 count_fsb -= ilen;
1764 offset_fsb += ilen;
1765 }
1766
1767 tip->i_d.di_flags2 = tip_flags2;
1768 return 0;
1769
1770 out_defer:
1771 xfs_defer_cancel(&dfops);
1772 out:
1773 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
1774 tip->i_d.di_flags2 = tip_flags2;
1775 return error;
1776 }
1777
1778 /* Swap the extents of two files by swapping data forks. */
1779 STATIC int
1780 xfs_swap_extent_forks(
1781 struct xfs_trans *tp,
1782 struct xfs_inode *ip,
1783 struct xfs_inode *tip,
1784 int *src_log_flags,
1785 int *target_log_flags)
1786 {
1787 struct xfs_ifork tempifp, *ifp, *tifp;
1788 int aforkblks = 0;
1789 int taforkblks = 0;
1790 xfs_extnum_t nextents;
1791 __uint64_t tmp;
1792 int error;
1793
1794 /*
1795 * Count the number of extended attribute blocks
1796 */
1797 if ( ((XFS_IFORK_Q(ip) != 0) && (ip->i_d.di_anextents > 0)) &&
1798 (ip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1799 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK,
1800 &aforkblks);
1801 if (error)
1802 return error;
1803 }
1804 if ( ((XFS_IFORK_Q(tip) != 0) && (tip->i_d.di_anextents > 0)) &&
1805 (tip->i_d.di_aformat != XFS_DINODE_FMT_LOCAL)) {
1806 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK,
1807 &taforkblks);
1808 if (error)
1809 return error;
1810 }
1811
1812 /*
1813 * Before we've swapped the forks, lets set the owners of the forks
1814 * appropriately. We have to do this as we are demand paging the btree
1815 * buffers, and so the validation done on read will expect the owner
1816 * field to be correctly set. Once we change the owners, we can swap the
1817 * inode forks.
1818 */
1819 if (ip->i_d.di_version == 3 &&
1820 ip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1821 (*target_log_flags) |= XFS_ILOG_DOWNER;
1822 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK,
1823 tip->i_ino, NULL);
1824 if (error)
1825 return error;
1826 }
1827
1828 if (tip->i_d.di_version == 3 &&
1829 tip->i_d.di_format == XFS_DINODE_FMT_BTREE) {
1830 (*src_log_flags) |= XFS_ILOG_DOWNER;
1831 error = xfs_bmbt_change_owner(tp, tip, XFS_DATA_FORK,
1832 ip->i_ino, NULL);
1833 if (error)
1834 return error;
1835 }
1836
1837 /*
1838 * Swap the data forks of the inodes
1839 */
1840 ifp = &ip->i_df;
1841 tifp = &tip->i_df;
1842 tempifp = *ifp; /* struct copy */
1843 *ifp = *tifp; /* struct copy */
1844 *tifp = tempifp; /* struct copy */
1845
1846 /*
1847 * Fix the on-disk inode values
1848 */
1849 tmp = (__uint64_t)ip->i_d.di_nblocks;
1850 ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
1851 tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
1852
1853 tmp = (__uint64_t) ip->i_d.di_nextents;
1854 ip->i_d.di_nextents = tip->i_d.di_nextents;
1855 tip->i_d.di_nextents = tmp;
1856
1857 tmp = (__uint64_t) ip->i_d.di_format;
1858 ip->i_d.di_format = tip->i_d.di_format;
1859 tip->i_d.di_format = tmp;
1860
1861 /*
1862 * The extents in the source inode could still contain speculative
1863 * preallocation beyond EOF (e.g. the file is open but not modified
1864 * while defrag is in progress). In that case, we need to copy over the
1865 * number of delalloc blocks the data fork in the source inode is
1866 * tracking beyond EOF so that when the fork is truncated away when the
1867 * temporary inode is unlinked we don't underrun the i_delayed_blks
1868 * counter on that inode.
1869 */
1870 ASSERT(tip->i_delayed_blks == 0);
1871 tip->i_delayed_blks = ip->i_delayed_blks;
1872 ip->i_delayed_blks = 0;
1873
1874 switch (ip->i_d.di_format) {
1875 case XFS_DINODE_FMT_EXTENTS:
1876 /*
1877 * If the extents fit in the inode, fix the pointer. Otherwise
1878 * it's already NULL or pointing to the extent.
1879 */
1880 nextents = xfs_iext_count(&ip->i_df);
1881 if (nextents <= XFS_INLINE_EXTS)
1882 ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
1883 (*src_log_flags) |= XFS_ILOG_DEXT;
1884 break;
1885 case XFS_DINODE_FMT_BTREE:
1886 ASSERT(ip->i_d.di_version < 3 ||
1887 (*src_log_flags & XFS_ILOG_DOWNER));
1888 (*src_log_flags) |= XFS_ILOG_DBROOT;
1889 break;
1890 }
1891
1892 switch (tip->i_d.di_format) {
1893 case XFS_DINODE_FMT_EXTENTS:
1894 /*
1895 * If the extents fit in the inode, fix the pointer. Otherwise
1896 * it's already NULL or pointing to the extent.
1897 */
1898 nextents = xfs_iext_count(&tip->i_df);
1899 if (nextents <= XFS_INLINE_EXTS)
1900 tifp->if_u1.if_extents = tifp->if_u2.if_inline_ext;
1901 (*target_log_flags) |= XFS_ILOG_DEXT;
1902 break;
1903 case XFS_DINODE_FMT_BTREE:
1904 (*target_log_flags) |= XFS_ILOG_DBROOT;
1905 ASSERT(tip->i_d.di_version < 3 ||
1906 (*target_log_flags & XFS_ILOG_DOWNER));
1907 break;
1908 }
1909
1910 return 0;
1911 }
1912
1913 int
1914 xfs_swap_extents(
1915 struct xfs_inode *ip, /* target inode */
1916 struct xfs_inode *tip, /* tmp inode */
1917 struct xfs_swapext *sxp)
1918 {
1919 struct xfs_mount *mp = ip->i_mount;
1920 struct xfs_trans *tp;
1921 struct xfs_bstat *sbp = &sxp->sx_stat;
1922 int src_log_flags, target_log_flags;
1923 int error = 0;
1924 int lock_flags;
1925 struct xfs_ifork *cowfp;
1926 __uint64_t f;
1927 int resblks;
1928
1929 /*
1930 * Lock the inodes against other IO, page faults and truncate to
1931 * begin with. Then we can ensure the inodes are flushed and have no
1932 * page cache safely. Once we have done this we can take the ilocks and
1933 * do the rest of the checks.
1934 */
1935 lock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1936 lock_flags = XFS_MMAPLOCK_EXCL;
1937 xfs_lock_two_inodes(ip, tip, XFS_MMAPLOCK_EXCL);
1938
1939 /* Verify that both files have the same format */
1940 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) {
1941 error = -EINVAL;
1942 goto out_unlock;
1943 }
1944
1945 /* Verify both files are either real-time or non-realtime */
1946 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
1947 error = -EINVAL;
1948 goto out_unlock;
1949 }
1950
1951 error = xfs_swap_extent_flush(ip);
1952 if (error)
1953 goto out_unlock;
1954 error = xfs_swap_extent_flush(tip);
1955 if (error)
1956 goto out_unlock;
1957
1958 /*
1959 * Extent "swapping" with rmap requires a permanent reservation and
1960 * a block reservation because it's really just a remap operation
1961 * performed with log redo items!
1962 */
1963 if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
1964 /*
1965 * Conceptually this shouldn't affect the shape of either
1966 * bmbt, but since we atomically move extents one by one,
1967 * we reserve enough space to rebuild both trees.
1968 */
1969 resblks = XFS_SWAP_RMAP_SPACE_RES(mp,
1970 XFS_IFORK_NEXTENTS(ip, XFS_DATA_FORK),
1971 XFS_DATA_FORK) +
1972 XFS_SWAP_RMAP_SPACE_RES(mp,
1973 XFS_IFORK_NEXTENTS(tip, XFS_DATA_FORK),
1974 XFS_DATA_FORK);
1975 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
1976 0, 0, &tp);
1977 } else
1978 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0,
1979 0, 0, &tp);
1980 if (error)
1981 goto out_unlock;
1982
1983 /*
1984 * Lock and join the inodes to the tansaction so that transaction commit
1985 * or cancel will unlock the inodes from this point onwards.
1986 */
1987 xfs_lock_two_inodes(ip, tip, XFS_ILOCK_EXCL);
1988 lock_flags |= XFS_ILOCK_EXCL;
1989 xfs_trans_ijoin(tp, ip, 0);
1990 xfs_trans_ijoin(tp, tip, 0);
1991
1992
1993 /* Verify all data are being swapped */
1994 if (sxp->sx_offset != 0 ||
1995 sxp->sx_length != ip->i_d.di_size ||
1996 sxp->sx_length != tip->i_d.di_size) {
1997 error = -EFAULT;
1998 goto out_trans_cancel;
1999 }
2000
2001 trace_xfs_swap_extent_before(ip, 0);
2002 trace_xfs_swap_extent_before(tip, 1);
2003
2004 /* check inode formats now that data is flushed */
2005 error = xfs_swap_extents_check_format(ip, tip);
2006 if (error) {
2007 xfs_notice(mp,
2008 "%s: inode 0x%llx format is incompatible for exchanging.",
2009 __func__, ip->i_ino);
2010 goto out_trans_cancel;
2011 }
2012
2013 /*
2014 * Compare the current change & modify times with that
2015 * passed in. If they differ, we abort this swap.
2016 * This is the mechanism used to ensure the calling
2017 * process that the file was not changed out from
2018 * under it.
2019 */
2020 if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
2021 (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
2022 (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
2023 (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
2024 error = -EBUSY;
2025 goto out_trans_cancel;
2026 }
2027
2028 /*
2029 * Note the trickiness in setting the log flags - we set the owner log
2030 * flag on the opposite inode (i.e. the inode we are setting the new
2031 * owner to be) because once we swap the forks and log that, log
2032 * recovery is going to see the fork as owned by the swapped inode,
2033 * not the pre-swapped inodes.
2034 */
2035 src_log_flags = XFS_ILOG_CORE;
2036 target_log_flags = XFS_ILOG_CORE;
2037
2038 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
2039 error = xfs_swap_extent_rmap(&tp, ip, tip);
2040 else
2041 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags,
2042 &target_log_flags);
2043 if (error)
2044 goto out_trans_cancel;
2045
2046 /* Do we have to swap reflink flags? */
2047 if ((ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK) ^
2048 (tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)) {
2049 f = ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
2050 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
2051 ip->i_d.di_flags2 |= tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
2052 tip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
2053 tip->i_d.di_flags2 |= f & XFS_DIFLAG2_REFLINK;
2054 cowfp = ip->i_cowfp;
2055 ip->i_cowfp = tip->i_cowfp;
2056 tip->i_cowfp = cowfp;
2057 xfs_inode_set_cowblocks_tag(ip);
2058 xfs_inode_set_cowblocks_tag(tip);
2059 }
2060
2061 xfs_trans_log_inode(tp, ip, src_log_flags);
2062 xfs_trans_log_inode(tp, tip, target_log_flags);
2063
2064 /*
2065 * If this is a synchronous mount, make sure that the
2066 * transaction goes to disk before returning to the user.
2067 */
2068 if (mp->m_flags & XFS_MOUNT_WSYNC)
2069 xfs_trans_set_sync(tp);
2070
2071 error = xfs_trans_commit(tp);
2072
2073 trace_xfs_swap_extent_after(ip, 0);
2074 trace_xfs_swap_extent_after(tip, 1);
2075
2076 out_unlock:
2077 xfs_iunlock(ip, lock_flags);
2078 xfs_iunlock(tip, lock_flags);
2079 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip));
2080 return error;
2081
2082 out_trans_cancel:
2083 xfs_trans_cancel(tp);
2084 goto out_unlock;
2085 }
Motorola kernel-slsi