Loading...
Note: File does not exist in v3.1.
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
4 * Copyright (c) 2012 Red Hat, Inc.
5 * All Rights Reserved.
6 */
7#include "xfs.h"
8#include "xfs_fs.h"
9#include "xfs_shared.h"
10#include "xfs_format.h"
11#include "xfs_log_format.h"
12#include "xfs_trans_resv.h"
13#include "xfs_bit.h"
14#include "xfs_mount.h"
15#include "xfs_defer.h"
16#include "xfs_inode.h"
17#include "xfs_btree.h"
18#include "xfs_trans.h"
19#include "xfs_alloc.h"
20#include "xfs_bmap.h"
21#include "xfs_bmap_util.h"
22#include "xfs_bmap_btree.h"
23#include "xfs_rtalloc.h"
24#include "xfs_error.h"
25#include "xfs_quota.h"
26#include "xfs_trans_space.h"
27#include "xfs_trace.h"
28#include "xfs_icache.h"
29#include "xfs_iomap.h"
30#include "xfs_reflink.h"
31
32/* Kernel only BMAP related definitions and functions */
33
34/*
35 * Convert the given file system block to a disk block. We have to treat it
36 * differently based on whether the file is a real time file or not, because the
37 * bmap code does.
38 */
39xfs_daddr_t
40xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
41{
42 if (XFS_IS_REALTIME_INODE(ip))
43 return XFS_FSB_TO_BB(ip->i_mount, fsb);
44 return XFS_FSB_TO_DADDR(ip->i_mount, fsb);
45}
46
47/*
48 * Routine to zero an extent on disk allocated to the specific inode.
49 *
50 * The VFS functions take a linearised filesystem block offset, so we have to
51 * convert the sparse xfs fsb to the right format first.
52 * VFS types are real funky, too.
53 */
54int
55xfs_zero_extent(
56 struct xfs_inode *ip,
57 xfs_fsblock_t start_fsb,
58 xfs_off_t count_fsb)
59{
60 struct xfs_mount *mp = ip->i_mount;
61 struct xfs_buftarg *target = xfs_inode_buftarg(ip);
62 xfs_daddr_t sector = xfs_fsb_to_db(ip, start_fsb);
63 sector_t block = XFS_BB_TO_FSBT(mp, sector);
64
65 return blkdev_issue_zeroout(target->bt_bdev,
66 block << (mp->m_super->s_blocksize_bits - 9),
67 count_fsb << (mp->m_super->s_blocksize_bits - 9),
68 GFP_NOFS, 0);
69}
70
71#ifdef CONFIG_XFS_RT
72int
73xfs_bmap_rtalloc(
74 struct xfs_bmalloca *ap) /* bmap alloc argument struct */
75{
76 int error; /* error return value */
77 xfs_mount_t *mp; /* mount point structure */
78 xfs_extlen_t prod = 0; /* product factor for allocators */
79 xfs_extlen_t mod = 0; /* product factor for allocators */
80 xfs_extlen_t ralen = 0; /* realtime allocation length */
81 xfs_extlen_t align; /* minimum allocation alignment */
82 xfs_rtblock_t rtb;
83
84 mp = ap->ip->i_mount;
85 align = xfs_get_extsz_hint(ap->ip);
86 prod = align / mp->m_sb.sb_rextsize;
87 error = xfs_bmap_extsize_align(mp, &ap->got, &ap->prev,
88 align, 1, ap->eof, 0,
89 ap->conv, &ap->offset, &ap->length);
90 if (error)
91 return error;
92 ASSERT(ap->length);
93 ASSERT(ap->length % mp->m_sb.sb_rextsize == 0);
94
95 /*
96 * If the offset & length are not perfectly aligned
97 * then kill prod, it will just get us in trouble.
98 */
99 div_u64_rem(ap->offset, align, &mod);
100 if (mod || ap->length % align)
101 prod = 1;
102 /*
103 * Set ralen to be the actual requested length in rtextents.
104 */
105 ralen = ap->length / mp->m_sb.sb_rextsize;
106 /*
107 * If the old value was close enough to MAXEXTLEN that
108 * we rounded up to it, cut it back so it's valid again.
109 * Note that if it's a really large request (bigger than
110 * MAXEXTLEN), we don't hear about that number, and can't
111 * adjust the starting point to match it.
112 */
113 if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN)
114 ralen = MAXEXTLEN / mp->m_sb.sb_rextsize;
115
116 /*
117 * Lock out modifications to both the RT bitmap and summary inodes
118 */
119 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL|XFS_ILOCK_RTBITMAP);
120 xfs_trans_ijoin(ap->tp, mp->m_rbmip, XFS_ILOCK_EXCL);
121 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL|XFS_ILOCK_RTSUM);
122 xfs_trans_ijoin(ap->tp, mp->m_rsumip, XFS_ILOCK_EXCL);
123
124 /*
125 * If it's an allocation to an empty file at offset 0,
126 * pick an extent that will space things out in the rt area.
127 */
128 if (ap->eof && ap->offset == 0) {
129 xfs_rtblock_t rtx; /* realtime extent no */
130
131 error = xfs_rtpick_extent(mp, ap->tp, ralen, &rtx);
132 if (error)
133 return error;
134 ap->blkno = rtx * mp->m_sb.sb_rextsize;
135 } else {
136 ap->blkno = 0;
137 }
138
139 xfs_bmap_adjacent(ap);
140
141 /*
142 * Realtime allocation, done through xfs_rtallocate_extent.
143 */
144 do_div(ap->blkno, mp->m_sb.sb_rextsize);
145 rtb = ap->blkno;
146 ap->length = ralen;
147 error = xfs_rtallocate_extent(ap->tp, ap->blkno, 1, ap->length,
148 &ralen, ap->wasdel, prod, &rtb);
149 if (error)
150 return error;
151
152 ap->blkno = rtb;
153 if (ap->blkno != NULLFSBLOCK) {
154 ap->blkno *= mp->m_sb.sb_rextsize;
155 ralen *= mp->m_sb.sb_rextsize;
156 ap->length = ralen;
157 ap->ip->i_d.di_nblocks += ralen;
158 xfs_trans_log_inode(ap->tp, ap->ip, XFS_ILOG_CORE);
159 if (ap->wasdel)
160 ap->ip->i_delayed_blks -= ralen;
161 /*
162 * Adjust the disk quota also. This was reserved
163 * earlier.
164 */
165 xfs_trans_mod_dquot_byino(ap->tp, ap->ip,
166 ap->wasdel ? XFS_TRANS_DQ_DELRTBCOUNT :
167 XFS_TRANS_DQ_RTBCOUNT, (long) ralen);
168 } else {
169 ap->length = 0;
170 }
171 return 0;
172}
173#endif /* CONFIG_XFS_RT */
174
175/*
176 * Extent tree block counting routines.
177 */
178
179/*
180 * Count leaf blocks given a range of extent records. Delayed allocation
181 * extents are not counted towards the totals.
182 */
183xfs_extnum_t
184xfs_bmap_count_leaves(
185 struct xfs_ifork *ifp,
186 xfs_filblks_t *count)
187{
188 struct xfs_iext_cursor icur;
189 struct xfs_bmbt_irec got;
190 xfs_extnum_t numrecs = 0;
191
192 for_each_xfs_iext(ifp, &icur, &got) {
193 if (!isnullstartblock(got.br_startblock)) {
194 *count += got.br_blockcount;
195 numrecs++;
196 }
197 }
198
199 return numrecs;
200}
201
202/*
203 * Count fsblocks of the given fork. Delayed allocation extents are
204 * not counted towards the totals.
205 */
206int
207xfs_bmap_count_blocks(
208 struct xfs_trans *tp,
209 struct xfs_inode *ip,
210 int whichfork,
211 xfs_extnum_t *nextents,
212 xfs_filblks_t *count)
213{
214 struct xfs_mount *mp = ip->i_mount;
215 struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
216 struct xfs_btree_cur *cur;
217 xfs_extlen_t btblocks = 0;
218 int error;
219
220 *nextents = 0;
221 *count = 0;
222
223 if (!ifp)
224 return 0;
225
226 switch (ifp->if_format) {
227 case XFS_DINODE_FMT_BTREE:
228 if (!(ifp->if_flags & XFS_IFEXTENTS)) {
229 error = xfs_iread_extents(tp, ip, whichfork);
230 if (error)
231 return error;
232 }
233
234 cur = xfs_bmbt_init_cursor(mp, tp, ip, whichfork);
235 error = xfs_btree_count_blocks(cur, &btblocks);
236 xfs_btree_del_cursor(cur, error);
237 if (error)
238 return error;
239
240 /*
241 * xfs_btree_count_blocks includes the root block contained in
242 * the inode fork in @btblocks, so subtract one because we're
243 * only interested in allocated disk blocks.
244 */
245 *count += btblocks - 1;
246
247 /* fall through */
248 case XFS_DINODE_FMT_EXTENTS:
249 *nextents = xfs_bmap_count_leaves(ifp, count);
250 break;
251 }
252
253 return 0;
254}
255
256static int
257xfs_getbmap_report_one(
258 struct xfs_inode *ip,
259 struct getbmapx *bmv,
260 struct kgetbmap *out,
261 int64_t bmv_end,
262 struct xfs_bmbt_irec *got)
263{
264 struct kgetbmap *p = out + bmv->bmv_entries;
265 bool shared = false;
266 int error;
267
268 error = xfs_reflink_trim_around_shared(ip, got, &shared);
269 if (error)
270 return error;
271
272 if (isnullstartblock(got->br_startblock) ||
273 got->br_startblock == DELAYSTARTBLOCK) {
274 /*
275 * Delalloc extents that start beyond EOF can occur due to
276 * speculative EOF allocation when the delalloc extent is larger
277 * than the largest freespace extent at conversion time. These
278 * extents cannot be converted by data writeback, so can exist
279 * here even if we are not supposed to be finding delalloc
280 * extents.
281 */
282 if (got->br_startoff < XFS_B_TO_FSB(ip->i_mount, XFS_ISIZE(ip)))
283 ASSERT((bmv->bmv_iflags & BMV_IF_DELALLOC) != 0);
284
285 p->bmv_oflags |= BMV_OF_DELALLOC;
286 p->bmv_block = -2;
287 } else {
288 p->bmv_block = xfs_fsb_to_db(ip, got->br_startblock);
289 }
290
291 if (got->br_state == XFS_EXT_UNWRITTEN &&
292 (bmv->bmv_iflags & BMV_IF_PREALLOC))
293 p->bmv_oflags |= BMV_OF_PREALLOC;
294
295 if (shared)
296 p->bmv_oflags |= BMV_OF_SHARED;
297
298 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, got->br_startoff);
299 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, got->br_blockcount);
300
301 bmv->bmv_offset = p->bmv_offset + p->bmv_length;
302 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset);
303 bmv->bmv_entries++;
304 return 0;
305}
306
307static void
308xfs_getbmap_report_hole(
309 struct xfs_inode *ip,
310 struct getbmapx *bmv,
311 struct kgetbmap *out,
312 int64_t bmv_end,
313 xfs_fileoff_t bno,
314 xfs_fileoff_t end)
315{
316 struct kgetbmap *p = out + bmv->bmv_entries;
317
318 if (bmv->bmv_iflags & BMV_IF_NO_HOLES)
319 return;
320
321 p->bmv_block = -1;
322 p->bmv_offset = XFS_FSB_TO_BB(ip->i_mount, bno);
323 p->bmv_length = XFS_FSB_TO_BB(ip->i_mount, end - bno);
324
325 bmv->bmv_offset = p->bmv_offset + p->bmv_length;
326 bmv->bmv_length = max(0LL, bmv_end - bmv->bmv_offset);
327 bmv->bmv_entries++;
328}
329
330static inline bool
331xfs_getbmap_full(
332 struct getbmapx *bmv)
333{
334 return bmv->bmv_length == 0 || bmv->bmv_entries >= bmv->bmv_count - 1;
335}
336
337static bool
338xfs_getbmap_next_rec(
339 struct xfs_bmbt_irec *rec,
340 xfs_fileoff_t total_end)
341{
342 xfs_fileoff_t end = rec->br_startoff + rec->br_blockcount;
343
344 if (end == total_end)
345 return false;
346
347 rec->br_startoff += rec->br_blockcount;
348 if (!isnullstartblock(rec->br_startblock) &&
349 rec->br_startblock != DELAYSTARTBLOCK)
350 rec->br_startblock += rec->br_blockcount;
351 rec->br_blockcount = total_end - end;
352 return true;
353}
354
355/*
356 * Get inode's extents as described in bmv, and format for output.
357 * Calls formatter to fill the user's buffer until all extents
358 * are mapped, until the passed-in bmv->bmv_count slots have
359 * been filled, or until the formatter short-circuits the loop,
360 * if it is tracking filled-in extents on its own.
361 */
362int /* error code */
363xfs_getbmap(
364 struct xfs_inode *ip,
365 struct getbmapx *bmv, /* user bmap structure */
366 struct kgetbmap *out)
367{
368 struct xfs_mount *mp = ip->i_mount;
369 int iflags = bmv->bmv_iflags;
370 int whichfork, lock, error = 0;
371 int64_t bmv_end, max_len;
372 xfs_fileoff_t bno, first_bno;
373 struct xfs_ifork *ifp;
374 struct xfs_bmbt_irec got, rec;
375 xfs_filblks_t len;
376 struct xfs_iext_cursor icur;
377
378 if (bmv->bmv_iflags & ~BMV_IF_VALID)
379 return -EINVAL;
380#ifndef DEBUG
381 /* Only allow CoW fork queries if we're debugging. */
382 if (iflags & BMV_IF_COWFORK)
383 return -EINVAL;
384#endif
385 if ((iflags & BMV_IF_ATTRFORK) && (iflags & BMV_IF_COWFORK))
386 return -EINVAL;
387
388 if (bmv->bmv_length < -1)
389 return -EINVAL;
390 bmv->bmv_entries = 0;
391 if (bmv->bmv_length == 0)
392 return 0;
393
394 if (iflags & BMV_IF_ATTRFORK)
395 whichfork = XFS_ATTR_FORK;
396 else if (iflags & BMV_IF_COWFORK)
397 whichfork = XFS_COW_FORK;
398 else
399 whichfork = XFS_DATA_FORK;
400 ifp = XFS_IFORK_PTR(ip, whichfork);
401
402 xfs_ilock(ip, XFS_IOLOCK_SHARED);
403 switch (whichfork) {
404 case XFS_ATTR_FORK:
405 if (!XFS_IFORK_Q(ip))
406 goto out_unlock_iolock;
407
408 max_len = 1LL << 32;
409 lock = xfs_ilock_attr_map_shared(ip);
410 break;
411 case XFS_COW_FORK:
412 /* No CoW fork? Just return */
413 if (!ifp)
414 goto out_unlock_iolock;
415
416 if (xfs_get_cowextsz_hint(ip))
417 max_len = mp->m_super->s_maxbytes;
418 else
419 max_len = XFS_ISIZE(ip);
420
421 lock = XFS_ILOCK_SHARED;
422 xfs_ilock(ip, lock);
423 break;
424 case XFS_DATA_FORK:
425 if (!(iflags & BMV_IF_DELALLOC) &&
426 (ip->i_delayed_blks || XFS_ISIZE(ip) > ip->i_d.di_size)) {
427 error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
428 if (error)
429 goto out_unlock_iolock;
430
431 /*
432 * Even after flushing the inode, there can still be
433 * delalloc blocks on the inode beyond EOF due to
434 * speculative preallocation. These are not removed
435 * until the release function is called or the inode
436 * is inactivated. Hence we cannot assert here that
437 * ip->i_delayed_blks == 0.
438 */
439 }
440
441 if (xfs_get_extsz_hint(ip) ||
442 (ip->i_d.di_flags &
443 (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND)))
444 max_len = mp->m_super->s_maxbytes;
445 else
446 max_len = XFS_ISIZE(ip);
447
448 lock = xfs_ilock_data_map_shared(ip);
449 break;
450 }
451
452 switch (ifp->if_format) {
453 case XFS_DINODE_FMT_EXTENTS:
454 case XFS_DINODE_FMT_BTREE:
455 break;
456 case XFS_DINODE_FMT_LOCAL:
457 /* Local format inode forks report no extents. */
458 goto out_unlock_ilock;
459 default:
460 error = -EINVAL;
461 goto out_unlock_ilock;
462 }
463
464 if (bmv->bmv_length == -1) {
465 max_len = XFS_FSB_TO_BB(mp, XFS_B_TO_FSB(mp, max_len));
466 bmv->bmv_length = max(0LL, max_len - bmv->bmv_offset);
467 }
468
469 bmv_end = bmv->bmv_offset + bmv->bmv_length;
470
471 first_bno = bno = XFS_BB_TO_FSBT(mp, bmv->bmv_offset);
472 len = XFS_BB_TO_FSB(mp, bmv->bmv_length);
473
474 if (!(ifp->if_flags & XFS_IFEXTENTS)) {
475 error = xfs_iread_extents(NULL, ip, whichfork);
476 if (error)
477 goto out_unlock_ilock;
478 }
479
480 if (!xfs_iext_lookup_extent(ip, ifp, bno, &icur, &got)) {
481 /*
482 * Report a whole-file hole if the delalloc flag is set to
483 * stay compatible with the old implementation.
484 */
485 if (iflags & BMV_IF_DELALLOC)
486 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno,
487 XFS_B_TO_FSB(mp, XFS_ISIZE(ip)));
488 goto out_unlock_ilock;
489 }
490
491 while (!xfs_getbmap_full(bmv)) {
492 xfs_trim_extent(&got, first_bno, len);
493
494 /*
495 * Report an entry for a hole if this extent doesn't directly
496 * follow the previous one.
497 */
498 if (got.br_startoff > bno) {
499 xfs_getbmap_report_hole(ip, bmv, out, bmv_end, bno,
500 got.br_startoff);
501 if (xfs_getbmap_full(bmv))
502 break;
503 }
504
505 /*
506 * In order to report shared extents accurately, we report each
507 * distinct shared / unshared part of a single bmbt record with
508 * an individual getbmapx record.
509 */
510 bno = got.br_startoff + got.br_blockcount;
511 rec = got;
512 do {
513 error = xfs_getbmap_report_one(ip, bmv, out, bmv_end,
514 &rec);
515 if (error || xfs_getbmap_full(bmv))
516 goto out_unlock_ilock;
517 } while (xfs_getbmap_next_rec(&rec, bno));
518
519 if (!xfs_iext_next_extent(ifp, &icur, &got)) {
520 xfs_fileoff_t end = XFS_B_TO_FSB(mp, XFS_ISIZE(ip));
521
522 out[bmv->bmv_entries - 1].bmv_oflags |= BMV_OF_LAST;
523
524 if (whichfork != XFS_ATTR_FORK && bno < end &&
525 !xfs_getbmap_full(bmv)) {
526 xfs_getbmap_report_hole(ip, bmv, out, bmv_end,
527 bno, end);
528 }
529 break;
530 }
531
532 if (bno >= first_bno + len)
533 break;
534 }
535
536out_unlock_ilock:
537 xfs_iunlock(ip, lock);
538out_unlock_iolock:
539 xfs_iunlock(ip, XFS_IOLOCK_SHARED);
540 return error;
541}
542
543/*
544 * Dead simple method of punching delalyed allocation blocks from a range in
545 * the inode. This will always punch out both the start and end blocks, even
546 * if the ranges only partially overlap them, so it is up to the caller to
547 * ensure that partial blocks are not passed in.
548 */
549int
550xfs_bmap_punch_delalloc_range(
551 struct xfs_inode *ip,
552 xfs_fileoff_t start_fsb,
553 xfs_fileoff_t length)
554{
555 struct xfs_ifork *ifp = &ip->i_df;
556 xfs_fileoff_t end_fsb = start_fsb + length;
557 struct xfs_bmbt_irec got, del;
558 struct xfs_iext_cursor icur;
559 int error = 0;
560
561 ASSERT(ifp->if_flags & XFS_IFEXTENTS);
562
563 xfs_ilock(ip, XFS_ILOCK_EXCL);
564 if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
565 goto out_unlock;
566
567 while (got.br_startoff + got.br_blockcount > start_fsb) {
568 del = got;
569 xfs_trim_extent(&del, start_fsb, length);
570
571 /*
572 * A delete can push the cursor forward. Step back to the
573 * previous extent on non-delalloc or extents outside the
574 * target range.
575 */
576 if (!del.br_blockcount ||
577 !isnullstartblock(del.br_startblock)) {
578 if (!xfs_iext_prev_extent(ifp, &icur, &got))
579 break;
580 continue;
581 }
582
583 error = xfs_bmap_del_extent_delay(ip, XFS_DATA_FORK, &icur,
584 &got, &del);
585 if (error || !xfs_iext_get_extent(ifp, &icur, &got))
586 break;
587 }
588
589out_unlock:
590 xfs_iunlock(ip, XFS_ILOCK_EXCL);
591 return error;
592}
593
594/*
595 * Test whether it is appropriate to check an inode for and free post EOF
596 * blocks. The 'force' parameter determines whether we should also consider
597 * regular files that are marked preallocated or append-only.
598 */
599bool
600xfs_can_free_eofblocks(struct xfs_inode *ip, bool force)
601{
602 /* prealloc/delalloc exists only on regular files */
603 if (!S_ISREG(VFS_I(ip)->i_mode))
604 return false;
605
606 /*
607 * Zero sized files with no cached pages and delalloc blocks will not
608 * have speculative prealloc/delalloc blocks to remove.
609 */
610 if (VFS_I(ip)->i_size == 0 &&
611 VFS_I(ip)->i_mapping->nrpages == 0 &&
612 ip->i_delayed_blks == 0)
613 return false;
614
615 /* If we haven't read in the extent list, then don't do it now. */
616 if (!(ip->i_df.if_flags & XFS_IFEXTENTS))
617 return false;
618
619 /*
620 * Do not free real preallocated or append-only files unless the file
621 * has delalloc blocks and we are forced to remove them.
622 */
623 if (ip->i_d.di_flags & (XFS_DIFLAG_PREALLOC | XFS_DIFLAG_APPEND))
624 if (!force || ip->i_delayed_blks == 0)
625 return false;
626
627 return true;
628}
629
630/*
631 * This is called to free any blocks beyond eof. The caller must hold
632 * IOLOCK_EXCL unless we are in the inode reclaim path and have the only
633 * reference to the inode.
634 */
635int
636xfs_free_eofblocks(
637 struct xfs_inode *ip)
638{
639 struct xfs_trans *tp;
640 int error;
641 xfs_fileoff_t end_fsb;
642 xfs_fileoff_t last_fsb;
643 xfs_filblks_t map_len;
644 int nimaps;
645 struct xfs_bmbt_irec imap;
646 struct xfs_mount *mp = ip->i_mount;
647
648 /*
649 * Figure out if there are any blocks beyond the end
650 * of the file. If not, then there is nothing to do.
651 */
652 end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)XFS_ISIZE(ip));
653 last_fsb = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
654 if (last_fsb <= end_fsb)
655 return 0;
656 map_len = last_fsb - end_fsb;
657
658 nimaps = 1;
659 xfs_ilock(ip, XFS_ILOCK_SHARED);
660 error = xfs_bmapi_read(ip, end_fsb, map_len, &imap, &nimaps, 0);
661 xfs_iunlock(ip, XFS_ILOCK_SHARED);
662
663 /*
664 * If there are blocks after the end of file, truncate the file to its
665 * current size to free them up.
666 */
667 if (!error && (nimaps != 0) &&
668 (imap.br_startblock != HOLESTARTBLOCK ||
669 ip->i_delayed_blks)) {
670 /*
671 * Attach the dquots to the inode up front.
672 */
673 error = xfs_qm_dqattach(ip);
674 if (error)
675 return error;
676
677 /* wait on dio to ensure i_size has settled */
678 inode_dio_wait(VFS_I(ip));
679
680 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0,
681 &tp);
682 if (error) {
683 ASSERT(XFS_FORCED_SHUTDOWN(mp));
684 return error;
685 }
686
687 xfs_ilock(ip, XFS_ILOCK_EXCL);
688 xfs_trans_ijoin(tp, ip, 0);
689
690 /*
691 * Do not update the on-disk file size. If we update the
692 * on-disk file size and then the system crashes before the
693 * contents of the file are flushed to disk then the files
694 * may be full of holes (ie NULL files bug).
695 */
696 error = xfs_itruncate_extents_flags(&tp, ip, XFS_DATA_FORK,
697 XFS_ISIZE(ip), XFS_BMAPI_NODISCARD);
698 if (error) {
699 /*
700 * If we get an error at this point we simply don't
701 * bother truncating the file.
702 */
703 xfs_trans_cancel(tp);
704 } else {
705 error = xfs_trans_commit(tp);
706 if (!error)
707 xfs_inode_clear_eofblocks_tag(ip);
708 }
709
710 xfs_iunlock(ip, XFS_ILOCK_EXCL);
711 }
712 return error;
713}
714
715int
716xfs_alloc_file_space(
717 struct xfs_inode *ip,
718 xfs_off_t offset,
719 xfs_off_t len,
720 int alloc_type)
721{
722 xfs_mount_t *mp = ip->i_mount;
723 xfs_off_t count;
724 xfs_filblks_t allocated_fsb;
725 xfs_filblks_t allocatesize_fsb;
726 xfs_extlen_t extsz, temp;
727 xfs_fileoff_t startoffset_fsb;
728 xfs_fileoff_t endoffset_fsb;
729 int nimaps;
730 int quota_flag;
731 int rt;
732 xfs_trans_t *tp;
733 xfs_bmbt_irec_t imaps[1], *imapp;
734 uint qblocks, resblks, resrtextents;
735 int error;
736
737 trace_xfs_alloc_file_space(ip);
738
739 if (XFS_FORCED_SHUTDOWN(mp))
740 return -EIO;
741
742 error = xfs_qm_dqattach(ip);
743 if (error)
744 return error;
745
746 if (len <= 0)
747 return -EINVAL;
748
749 rt = XFS_IS_REALTIME_INODE(ip);
750 extsz = xfs_get_extsz_hint(ip);
751
752 count = len;
753 imapp = &imaps[0];
754 nimaps = 1;
755 startoffset_fsb = XFS_B_TO_FSBT(mp, offset);
756 endoffset_fsb = XFS_B_TO_FSB(mp, offset + count);
757 allocatesize_fsb = endoffset_fsb - startoffset_fsb;
758
759 /*
760 * Allocate file space until done or until there is an error
761 */
762 while (allocatesize_fsb && !error) {
763 xfs_fileoff_t s, e;
764
765 /*
766 * Determine space reservations for data/realtime.
767 */
768 if (unlikely(extsz)) {
769 s = startoffset_fsb;
770 do_div(s, extsz);
771 s *= extsz;
772 e = startoffset_fsb + allocatesize_fsb;
773 div_u64_rem(startoffset_fsb, extsz, &temp);
774 if (temp)
775 e += temp;
776 div_u64_rem(e, extsz, &temp);
777 if (temp)
778 e += extsz - temp;
779 } else {
780 s = 0;
781 e = allocatesize_fsb;
782 }
783
784 /*
785 * The transaction reservation is limited to a 32-bit block
786 * count, hence we need to limit the number of blocks we are
787 * trying to reserve to avoid an overflow. We can't allocate
788 * more than @nimaps extents, and an extent is limited on disk
789 * to MAXEXTLEN (21 bits), so use that to enforce the limit.
790 */
791 resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps));
792 if (unlikely(rt)) {
793 resrtextents = qblocks = resblks;
794 resrtextents /= mp->m_sb.sb_rextsize;
795 resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
796 quota_flag = XFS_QMOPT_RES_RTBLKS;
797 } else {
798 resrtextents = 0;
799 resblks = qblocks = XFS_DIOSTRAT_SPACE_RES(mp, resblks);
800 quota_flag = XFS_QMOPT_RES_REGBLKS;
801 }
802
803 /*
804 * Allocate and setup the transaction.
805 */
806 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks,
807 resrtextents, 0, &tp);
808
809 /*
810 * Check for running out of space
811 */
812 if (error) {
813 /*
814 * Free the transaction structure.
815 */
816 ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
817 break;
818 }
819 xfs_ilock(ip, XFS_ILOCK_EXCL);
820 error = xfs_trans_reserve_quota_nblks(tp, ip, qblocks,
821 0, quota_flag);
822 if (error)
823 goto error1;
824
825 xfs_trans_ijoin(tp, ip, 0);
826
827 error = xfs_bmapi_write(tp, ip, startoffset_fsb,
828 allocatesize_fsb, alloc_type, 0, imapp,
829 &nimaps);
830 if (error)
831 goto error0;
832
833 /*
834 * Complete the transaction
835 */
836 error = xfs_trans_commit(tp);
837 xfs_iunlock(ip, XFS_ILOCK_EXCL);
838 if (error)
839 break;
840
841 allocated_fsb = imapp->br_blockcount;
842
843 if (nimaps == 0) {
844 error = -ENOSPC;
845 break;
846 }
847
848 startoffset_fsb += allocated_fsb;
849 allocatesize_fsb -= allocated_fsb;
850 }
851
852 return error;
853
854error0: /* unlock inode, unreserve quota blocks, cancel trans */
855 xfs_trans_unreserve_quota_nblks(tp, ip, (long)qblocks, 0, quota_flag);
856
857error1: /* Just cancel transaction */
858 xfs_trans_cancel(tp);
859 xfs_iunlock(ip, XFS_ILOCK_EXCL);
860 return error;
861}
862
863static int
864xfs_unmap_extent(
865 struct xfs_inode *ip,
866 xfs_fileoff_t startoffset_fsb,
867 xfs_filblks_t len_fsb,
868 int *done)
869{
870 struct xfs_mount *mp = ip->i_mount;
871 struct xfs_trans *tp;
872 uint resblks = XFS_DIOSTRAT_SPACE_RES(mp, 0);
873 int error;
874
875 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp);
876 if (error) {
877 ASSERT(error == -ENOSPC || XFS_FORCED_SHUTDOWN(mp));
878 return error;
879 }
880
881 xfs_ilock(ip, XFS_ILOCK_EXCL);
882 error = xfs_trans_reserve_quota(tp, mp, ip->i_udquot, ip->i_gdquot,
883 ip->i_pdquot, resblks, 0, XFS_QMOPT_RES_REGBLKS);
884 if (error)
885 goto out_trans_cancel;
886
887 xfs_trans_ijoin(tp, ip, 0);
888
889 error = xfs_bunmapi(tp, ip, startoffset_fsb, len_fsb, 0, 2, done);
890 if (error)
891 goto out_trans_cancel;
892
893 error = xfs_trans_commit(tp);
894out_unlock:
895 xfs_iunlock(ip, XFS_ILOCK_EXCL);
896 return error;
897
898out_trans_cancel:
899 xfs_trans_cancel(tp);
900 goto out_unlock;
901}
902
903/* Caller must first wait for the completion of any pending DIOs if required. */
904int
905xfs_flush_unmap_range(
906 struct xfs_inode *ip,
907 xfs_off_t offset,
908 xfs_off_t len)
909{
910 struct xfs_mount *mp = ip->i_mount;
911 struct inode *inode = VFS_I(ip);
912 xfs_off_t rounding, start, end;
913 int error;
914
915 rounding = max_t(xfs_off_t, 1 << mp->m_sb.sb_blocklog, PAGE_SIZE);
916 start = round_down(offset, rounding);
917 end = round_up(offset + len, rounding) - 1;
918
919 error = filemap_write_and_wait_range(inode->i_mapping, start, end);
920 if (error)
921 return error;
922 truncate_pagecache_range(inode, start, end);
923 return 0;
924}
925
926int
927xfs_free_file_space(
928 struct xfs_inode *ip,
929 xfs_off_t offset,
930 xfs_off_t len)
931{
932 struct xfs_mount *mp = ip->i_mount;
933 xfs_fileoff_t startoffset_fsb;
934 xfs_fileoff_t endoffset_fsb;
935 int done = 0, error;
936
937 trace_xfs_free_file_space(ip);
938
939 error = xfs_qm_dqattach(ip);
940 if (error)
941 return error;
942
943 if (len <= 0) /* if nothing being freed */
944 return 0;
945
946 startoffset_fsb = XFS_B_TO_FSB(mp, offset);
947 endoffset_fsb = XFS_B_TO_FSBT(mp, offset + len);
948
949 /*
950 * Need to zero the stuff we're not freeing, on disk.
951 */
952 if (endoffset_fsb > startoffset_fsb) {
953 while (!done) {
954 error = xfs_unmap_extent(ip, startoffset_fsb,
955 endoffset_fsb - startoffset_fsb, &done);
956 if (error)
957 return error;
958 }
959 }
960
961 /*
962 * Now that we've unmap all full blocks we'll have to zero out any
963 * partial block at the beginning and/or end. iomap_zero_range is smart
964 * enough to skip any holes, including those we just created, but we
965 * must take care not to zero beyond EOF and enlarge i_size.
966 */
967 if (offset >= XFS_ISIZE(ip))
968 return 0;
969 if (offset + len > XFS_ISIZE(ip))
970 len = XFS_ISIZE(ip) - offset;
971 error = iomap_zero_range(VFS_I(ip), offset, len, NULL,
972 &xfs_buffered_write_iomap_ops);
973 if (error)
974 return error;
975
976 /*
977 * If we zeroed right up to EOF and EOF straddles a page boundary we
978 * must make sure that the post-EOF area is also zeroed because the
979 * page could be mmap'd and iomap_zero_range doesn't do that for us.
980 * Writeback of the eof page will do this, albeit clumsily.
981 */
982 if (offset + len >= XFS_ISIZE(ip) && offset_in_page(offset + len) > 0) {
983 error = filemap_write_and_wait_range(VFS_I(ip)->i_mapping,
984 round_down(offset + len, PAGE_SIZE), LLONG_MAX);
985 }
986
987 return error;
988}
989
990static int
991xfs_prepare_shift(
992 struct xfs_inode *ip,
993 loff_t offset)
994{
995 struct xfs_mount *mp = ip->i_mount;
996 int error;
997
998 /*
999 * Trim eofblocks to avoid shifting uninitialized post-eof preallocation
1000 * into the accessible region of the file.
1001 */
1002 if (xfs_can_free_eofblocks(ip, true)) {
1003 error = xfs_free_eofblocks(ip);
1004 if (error)
1005 return error;
1006 }
1007
1008 /*
1009 * Shift operations must stabilize the start block offset boundary along
1010 * with the full range of the operation. If we don't, a COW writeback
1011 * completion could race with an insert, front merge with the start
1012 * extent (after split) during the shift and corrupt the file. Start
1013 * with the block just prior to the start to stabilize the boundary.
1014 */
1015 offset = round_down(offset, 1 << mp->m_sb.sb_blocklog);
1016 if (offset)
1017 offset -= (1 << mp->m_sb.sb_blocklog);
1018
1019 /*
1020 * Writeback and invalidate cache for the remainder of the file as we're
1021 * about to shift down every extent from offset to EOF.
1022 */
1023 error = xfs_flush_unmap_range(ip, offset, XFS_ISIZE(ip));
1024 if (error)
1025 return error;
1026
1027 /*
1028 * Clean out anything hanging around in the cow fork now that
1029 * we've flushed all the dirty data out to disk to avoid having
1030 * CoW extents at the wrong offsets.
1031 */
1032 if (xfs_inode_has_cow_data(ip)) {
1033 error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF,
1034 true);
1035 if (error)
1036 return error;
1037 }
1038
1039 return 0;
1040}
1041
1042/*
1043 * xfs_collapse_file_space()
1044 * This routine frees disk space and shift extent for the given file.
1045 * The first thing we do is to free data blocks in the specified range
1046 * by calling xfs_free_file_space(). It would also sync dirty data
1047 * and invalidate page cache over the region on which collapse range
1048 * is working. And Shift extent records to the left to cover a hole.
1049 * RETURNS:
1050 * 0 on success
1051 * errno on error
1052 *
1053 */
1054int
1055xfs_collapse_file_space(
1056 struct xfs_inode *ip,
1057 xfs_off_t offset,
1058 xfs_off_t len)
1059{
1060 struct xfs_mount *mp = ip->i_mount;
1061 struct xfs_trans *tp;
1062 int error;
1063 xfs_fileoff_t next_fsb = XFS_B_TO_FSB(mp, offset + len);
1064 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len);
1065 bool done = false;
1066
1067 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1068 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL));
1069
1070 trace_xfs_collapse_file_space(ip);
1071
1072 error = xfs_free_file_space(ip, offset, len);
1073 if (error)
1074 return error;
1075
1076 error = xfs_prepare_shift(ip, offset);
1077 if (error)
1078 return error;
1079
1080 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0, 0, &tp);
1081 if (error)
1082 return error;
1083
1084 xfs_ilock(ip, XFS_ILOCK_EXCL);
1085 xfs_trans_ijoin(tp, ip, 0);
1086
1087 while (!done) {
1088 error = xfs_bmap_collapse_extents(tp, ip, &next_fsb, shift_fsb,
1089 &done);
1090 if (error)
1091 goto out_trans_cancel;
1092 if (done)
1093 break;
1094
1095 /* finish any deferred frees and roll the transaction */
1096 error = xfs_defer_finish(&tp);
1097 if (error)
1098 goto out_trans_cancel;
1099 }
1100
1101 error = xfs_trans_commit(tp);
1102 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1103 return error;
1104
1105out_trans_cancel:
1106 xfs_trans_cancel(tp);
1107 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1108 return error;
1109}
1110
1111/*
1112 * xfs_insert_file_space()
1113 * This routine create hole space by shifting extents for the given file.
1114 * The first thing we do is to sync dirty data and invalidate page cache
1115 * over the region on which insert range is working. And split an extent
1116 * to two extents at given offset by calling xfs_bmap_split_extent.
1117 * And shift all extent records which are laying between [offset,
1118 * last allocated extent] to the right to reserve hole range.
1119 * RETURNS:
1120 * 0 on success
1121 * errno on error
1122 */
1123int
1124xfs_insert_file_space(
1125 struct xfs_inode *ip,
1126 loff_t offset,
1127 loff_t len)
1128{
1129 struct xfs_mount *mp = ip->i_mount;
1130 struct xfs_trans *tp;
1131 int error;
1132 xfs_fileoff_t stop_fsb = XFS_B_TO_FSB(mp, offset);
1133 xfs_fileoff_t next_fsb = NULLFSBLOCK;
1134 xfs_fileoff_t shift_fsb = XFS_B_TO_FSB(mp, len);
1135 bool done = false;
1136
1137 ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL));
1138 ASSERT(xfs_isilocked(ip, XFS_MMAPLOCK_EXCL));
1139
1140 trace_xfs_insert_file_space(ip);
1141
1142 error = xfs_bmap_can_insert_extents(ip, stop_fsb, shift_fsb);
1143 if (error)
1144 return error;
1145
1146 error = xfs_prepare_shift(ip, offset);
1147 if (error)
1148 return error;
1149
1150 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write,
1151 XFS_DIOSTRAT_SPACE_RES(mp, 0), 0, 0, &tp);
1152 if (error)
1153 return error;
1154
1155 xfs_ilock(ip, XFS_ILOCK_EXCL);
1156 xfs_trans_ijoin(tp, ip, 0);
1157
1158 /*
1159 * The extent shifting code works on extent granularity. So, if stop_fsb
1160 * is not the starting block of extent, we need to split the extent at
1161 * stop_fsb.
1162 */
1163 error = xfs_bmap_split_extent(tp, ip, stop_fsb);
1164 if (error)
1165 goto out_trans_cancel;
1166
1167 do {
1168 error = xfs_defer_finish(&tp);
1169 if (error)
1170 goto out_trans_cancel;
1171
1172 error = xfs_bmap_insert_extents(tp, ip, &next_fsb, shift_fsb,
1173 &done, stop_fsb);
1174 if (error)
1175 goto out_trans_cancel;
1176 } while (!done);
1177
1178 error = xfs_trans_commit(tp);
1179 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1180 return error;
1181
1182out_trans_cancel:
1183 xfs_trans_cancel(tp);
1184 xfs_iunlock(ip, XFS_ILOCK_EXCL);
1185 return error;
1186}
1187
1188/*
1189 * We need to check that the format of the data fork in the temporary inode is
1190 * valid for the target inode before doing the swap. This is not a problem with
1191 * attr1 because of the fixed fork offset, but attr2 has a dynamically sized
1192 * data fork depending on the space the attribute fork is taking so we can get
1193 * invalid formats on the target inode.
1194 *
1195 * E.g. target has space for 7 extents in extent format, temp inode only has
1196 * space for 6. If we defragment down to 7 extents, then the tmp format is a
1197 * btree, but when swapped it needs to be in extent format. Hence we can't just
1198 * blindly swap data forks on attr2 filesystems.
1199 *
1200 * Note that we check the swap in both directions so that we don't end up with
1201 * a corrupt temporary inode, either.
1202 *
1203 * Note that fixing the way xfs_fsr sets up the attribute fork in the source
1204 * inode will prevent this situation from occurring, so all we do here is
1205 * reject and log the attempt. basically we are putting the responsibility on
1206 * userspace to get this right.
1207 */
1208static int
1209xfs_swap_extents_check_format(
1210 struct xfs_inode *ip, /* target inode */
1211 struct xfs_inode *tip) /* tmp inode */
1212{
1213 struct xfs_ifork *ifp = &ip->i_df;
1214 struct xfs_ifork *tifp = &tip->i_df;
1215
1216 /* User/group/project quota ids must match if quotas are enforced. */
1217 if (XFS_IS_QUOTA_ON(ip->i_mount) &&
1218 (!uid_eq(VFS_I(ip)->i_uid, VFS_I(tip)->i_uid) ||
1219 !gid_eq(VFS_I(ip)->i_gid, VFS_I(tip)->i_gid) ||
1220 ip->i_d.di_projid != tip->i_d.di_projid))
1221 return -EINVAL;
1222
1223 /* Should never get a local format */
1224 if (ifp->if_format == XFS_DINODE_FMT_LOCAL ||
1225 tifp->if_format == XFS_DINODE_FMT_LOCAL)
1226 return -EINVAL;
1227
1228 /*
1229 * if the target inode has less extents that then temporary inode then
1230 * why did userspace call us?
1231 */
1232 if (ifp->if_nextents < tifp->if_nextents)
1233 return -EINVAL;
1234
1235 /*
1236 * If we have to use the (expensive) rmap swap method, we can
1237 * handle any number of extents and any format.
1238 */
1239 if (xfs_sb_version_hasrmapbt(&ip->i_mount->m_sb))
1240 return 0;
1241
1242 /*
1243 * if the target inode is in extent form and the temp inode is in btree
1244 * form then we will end up with the target inode in the wrong format
1245 * as we already know there are less extents in the temp inode.
1246 */
1247 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1248 tifp->if_format == XFS_DINODE_FMT_BTREE)
1249 return -EINVAL;
1250
1251 /* Check temp in extent form to max in target */
1252 if (tifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1253 tifp->if_nextents > XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1254 return -EINVAL;
1255
1256 /* Check target in extent form to max in temp */
1257 if (ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
1258 ifp->if_nextents > XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1259 return -EINVAL;
1260
1261 /*
1262 * If we are in a btree format, check that the temp root block will fit
1263 * in the target and that it has enough extents to be in btree format
1264 * in the target.
1265 *
1266 * Note that we have to be careful to allow btree->extent conversions
1267 * (a common defrag case) which will occur when the temp inode is in
1268 * extent format...
1269 */
1270 if (tifp->if_format == XFS_DINODE_FMT_BTREE) {
1271 if (XFS_IFORK_Q(ip) &&
1272 XFS_BMAP_BMDR_SPACE(tifp->if_broot) > XFS_IFORK_BOFF(ip))
1273 return -EINVAL;
1274 if (tifp->if_nextents <= XFS_IFORK_MAXEXT(ip, XFS_DATA_FORK))
1275 return -EINVAL;
1276 }
1277
1278 /* Reciprocal target->temp btree format checks */
1279 if (ifp->if_format == XFS_DINODE_FMT_BTREE) {
1280 if (XFS_IFORK_Q(tip) &&
1281 XFS_BMAP_BMDR_SPACE(ip->i_df.if_broot) > XFS_IFORK_BOFF(tip))
1282 return -EINVAL;
1283 if (ifp->if_nextents <= XFS_IFORK_MAXEXT(tip, XFS_DATA_FORK))
1284 return -EINVAL;
1285 }
1286
1287 return 0;
1288}
1289
1290static int
1291xfs_swap_extent_flush(
1292 struct xfs_inode *ip)
1293{
1294 int error;
1295
1296 error = filemap_write_and_wait(VFS_I(ip)->i_mapping);
1297 if (error)
1298 return error;
1299 truncate_pagecache_range(VFS_I(ip), 0, -1);
1300
1301 /* Verify O_DIRECT for ftmp */
1302 if (VFS_I(ip)->i_mapping->nrpages)
1303 return -EINVAL;
1304 return 0;
1305}
1306
1307/*
1308 * Move extents from one file to another, when rmap is enabled.
1309 */
1310STATIC int
1311xfs_swap_extent_rmap(
1312 struct xfs_trans **tpp,
1313 struct xfs_inode *ip,
1314 struct xfs_inode *tip)
1315{
1316 struct xfs_trans *tp = *tpp;
1317 struct xfs_bmbt_irec irec;
1318 struct xfs_bmbt_irec uirec;
1319 struct xfs_bmbt_irec tirec;
1320 xfs_fileoff_t offset_fsb;
1321 xfs_fileoff_t end_fsb;
1322 xfs_filblks_t count_fsb;
1323 int error;
1324 xfs_filblks_t ilen;
1325 xfs_filblks_t rlen;
1326 int nimaps;
1327 uint64_t tip_flags2;
1328
1329 /*
1330 * If the source file has shared blocks, we must flag the donor
1331 * file as having shared blocks so that we get the shared-block
1332 * rmap functions when we go to fix up the rmaps. The flags
1333 * will be switch for reals later.
1334 */
1335 tip_flags2 = tip->i_d.di_flags2;
1336 if (ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)
1337 tip->i_d.di_flags2 |= XFS_DIFLAG2_REFLINK;
1338
1339 offset_fsb = 0;
1340 end_fsb = XFS_B_TO_FSB(ip->i_mount, i_size_read(VFS_I(ip)));
1341 count_fsb = (xfs_filblks_t)(end_fsb - offset_fsb);
1342
1343 while (count_fsb) {
1344 /* Read extent from the donor file */
1345 nimaps = 1;
1346 error = xfs_bmapi_read(tip, offset_fsb, count_fsb, &tirec,
1347 &nimaps, 0);
1348 if (error)
1349 goto out;
1350 ASSERT(nimaps == 1);
1351 ASSERT(tirec.br_startblock != DELAYSTARTBLOCK);
1352
1353 trace_xfs_swap_extent_rmap_remap(tip, &tirec);
1354 ilen = tirec.br_blockcount;
1355
1356 /* Unmap the old blocks in the source file. */
1357 while (tirec.br_blockcount) {
1358 ASSERT(tp->t_firstblock == NULLFSBLOCK);
1359 trace_xfs_swap_extent_rmap_remap_piece(tip, &tirec);
1360
1361 /* Read extent from the source file */
1362 nimaps = 1;
1363 error = xfs_bmapi_read(ip, tirec.br_startoff,
1364 tirec.br_blockcount, &irec,
1365 &nimaps, 0);
1366 if (error)
1367 goto out;
1368 ASSERT(nimaps == 1);
1369 ASSERT(tirec.br_startoff == irec.br_startoff);
1370 trace_xfs_swap_extent_rmap_remap_piece(ip, &irec);
1371
1372 /* Trim the extent. */
1373 uirec = tirec;
1374 uirec.br_blockcount = rlen = min_t(xfs_filblks_t,
1375 tirec.br_blockcount,
1376 irec.br_blockcount);
1377 trace_xfs_swap_extent_rmap_remap_piece(tip, &uirec);
1378
1379 /* Remove the mapping from the donor file. */
1380 xfs_bmap_unmap_extent(tp, tip, &uirec);
1381
1382 /* Remove the mapping from the source file. */
1383 xfs_bmap_unmap_extent(tp, ip, &irec);
1384
1385 /* Map the donor file's blocks into the source file. */
1386 xfs_bmap_map_extent(tp, ip, &uirec);
1387
1388 /* Map the source file's blocks into the donor file. */
1389 xfs_bmap_map_extent(tp, tip, &irec);
1390
1391 error = xfs_defer_finish(tpp);
1392 tp = *tpp;
1393 if (error)
1394 goto out;
1395
1396 tirec.br_startoff += rlen;
1397 if (tirec.br_startblock != HOLESTARTBLOCK &&
1398 tirec.br_startblock != DELAYSTARTBLOCK)
1399 tirec.br_startblock += rlen;
1400 tirec.br_blockcount -= rlen;
1401 }
1402
1403 /* Roll on... */
1404 count_fsb -= ilen;
1405 offset_fsb += ilen;
1406 }
1407
1408 tip->i_d.di_flags2 = tip_flags2;
1409 return 0;
1410
1411out:
1412 trace_xfs_swap_extent_rmap_error(ip, error, _RET_IP_);
1413 tip->i_d.di_flags2 = tip_flags2;
1414 return error;
1415}
1416
1417/* Swap the extents of two files by swapping data forks. */
1418STATIC int
1419xfs_swap_extent_forks(
1420 struct xfs_trans *tp,
1421 struct xfs_inode *ip,
1422 struct xfs_inode *tip,
1423 int *src_log_flags,
1424 int *target_log_flags)
1425{
1426 xfs_filblks_t aforkblks = 0;
1427 xfs_filblks_t taforkblks = 0;
1428 xfs_extnum_t junk;
1429 uint64_t tmp;
1430 int error;
1431
1432 /*
1433 * Count the number of extended attribute blocks
1434 */
1435 if (XFS_IFORK_Q(ip) && ip->i_afp->if_nextents > 0 &&
1436 ip->i_afp->if_format != XFS_DINODE_FMT_LOCAL) {
1437 error = xfs_bmap_count_blocks(tp, ip, XFS_ATTR_FORK, &junk,
1438 &aforkblks);
1439 if (error)
1440 return error;
1441 }
1442 if (XFS_IFORK_Q(tip) && tip->i_afp->if_nextents > 0 &&
1443 tip->i_afp->if_format != XFS_DINODE_FMT_LOCAL) {
1444 error = xfs_bmap_count_blocks(tp, tip, XFS_ATTR_FORK, &junk,
1445 &taforkblks);
1446 if (error)
1447 return error;
1448 }
1449
1450 /*
1451 * Btree format (v3) inodes have the inode number stamped in the bmbt
1452 * block headers. We can't start changing the bmbt blocks until the
1453 * inode owner change is logged so recovery does the right thing in the
1454 * event of a crash. Set the owner change log flags now and leave the
1455 * bmbt scan as the last step.
1456 */
1457 if (xfs_sb_version_has_v3inode(&ip->i_mount->m_sb)) {
1458 if (ip->i_df.if_format == XFS_DINODE_FMT_BTREE)
1459 (*target_log_flags) |= XFS_ILOG_DOWNER;
1460 if (tip->i_df.if_format == XFS_DINODE_FMT_BTREE)
1461 (*src_log_flags) |= XFS_ILOG_DOWNER;
1462 }
1463
1464 /*
1465 * Swap the data forks of the inodes
1466 */
1467 swap(ip->i_df, tip->i_df);
1468
1469 /*
1470 * Fix the on-disk inode values
1471 */
1472 tmp = (uint64_t)ip->i_d.di_nblocks;
1473 ip->i_d.di_nblocks = tip->i_d.di_nblocks - taforkblks + aforkblks;
1474 tip->i_d.di_nblocks = tmp + taforkblks - aforkblks;
1475
1476 /*
1477 * The extents in the source inode could still contain speculative
1478 * preallocation beyond EOF (e.g. the file is open but not modified
1479 * while defrag is in progress). In that case, we need to copy over the
1480 * number of delalloc blocks the data fork in the source inode is
1481 * tracking beyond EOF so that when the fork is truncated away when the
1482 * temporary inode is unlinked we don't underrun the i_delayed_blks
1483 * counter on that inode.
1484 */
1485 ASSERT(tip->i_delayed_blks == 0);
1486 tip->i_delayed_blks = ip->i_delayed_blks;
1487 ip->i_delayed_blks = 0;
1488
1489 switch (ip->i_df.if_format) {
1490 case XFS_DINODE_FMT_EXTENTS:
1491 (*src_log_flags) |= XFS_ILOG_DEXT;
1492 break;
1493 case XFS_DINODE_FMT_BTREE:
1494 ASSERT(!xfs_sb_version_has_v3inode(&ip->i_mount->m_sb) ||
1495 (*src_log_flags & XFS_ILOG_DOWNER));
1496 (*src_log_flags) |= XFS_ILOG_DBROOT;
1497 break;
1498 }
1499
1500 switch (tip->i_df.if_format) {
1501 case XFS_DINODE_FMT_EXTENTS:
1502 (*target_log_flags) |= XFS_ILOG_DEXT;
1503 break;
1504 case XFS_DINODE_FMT_BTREE:
1505 (*target_log_flags) |= XFS_ILOG_DBROOT;
1506 ASSERT(!xfs_sb_version_has_v3inode(&ip->i_mount->m_sb) ||
1507 (*target_log_flags & XFS_ILOG_DOWNER));
1508 break;
1509 }
1510
1511 return 0;
1512}
1513
1514/*
1515 * Fix up the owners of the bmbt blocks to refer to the current inode. The
1516 * change owner scan attempts to order all modified buffers in the current
1517 * transaction. In the event of ordered buffer failure, the offending buffer is
1518 * physically logged as a fallback and the scan returns -EAGAIN. We must roll
1519 * the transaction in this case to replenish the fallback log reservation and
1520 * restart the scan. This process repeats until the scan completes.
1521 */
1522static int
1523xfs_swap_change_owner(
1524 struct xfs_trans **tpp,
1525 struct xfs_inode *ip,
1526 struct xfs_inode *tmpip)
1527{
1528 int error;
1529 struct xfs_trans *tp = *tpp;
1530
1531 do {
1532 error = xfs_bmbt_change_owner(tp, ip, XFS_DATA_FORK, ip->i_ino,
1533 NULL);
1534 /* success or fatal error */
1535 if (error != -EAGAIN)
1536 break;
1537
1538 error = xfs_trans_roll(tpp);
1539 if (error)
1540 break;
1541 tp = *tpp;
1542
1543 /*
1544 * Redirty both inodes so they can relog and keep the log tail
1545 * moving forward.
1546 */
1547 xfs_trans_ijoin(tp, ip, 0);
1548 xfs_trans_ijoin(tp, tmpip, 0);
1549 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
1550 xfs_trans_log_inode(tp, tmpip, XFS_ILOG_CORE);
1551 } while (true);
1552
1553 return error;
1554}
1555
1556int
1557xfs_swap_extents(
1558 struct xfs_inode *ip, /* target inode */
1559 struct xfs_inode *tip, /* tmp inode */
1560 struct xfs_swapext *sxp)
1561{
1562 struct xfs_mount *mp = ip->i_mount;
1563 struct xfs_trans *tp;
1564 struct xfs_bstat *sbp = &sxp->sx_stat;
1565 int src_log_flags, target_log_flags;
1566 int error = 0;
1567 int lock_flags;
1568 uint64_t f;
1569 int resblks = 0;
1570 unsigned int flags = 0;
1571
1572 /*
1573 * Lock the inodes against other IO, page faults and truncate to
1574 * begin with. Then we can ensure the inodes are flushed and have no
1575 * page cache safely. Once we have done this we can take the ilocks and
1576 * do the rest of the checks.
1577 */
1578 lock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1579 lock_flags = XFS_MMAPLOCK_EXCL;
1580 xfs_lock_two_inodes(ip, XFS_MMAPLOCK_EXCL, tip, XFS_MMAPLOCK_EXCL);
1581
1582 /* Verify that both files have the same format */
1583 if ((VFS_I(ip)->i_mode & S_IFMT) != (VFS_I(tip)->i_mode & S_IFMT)) {
1584 error = -EINVAL;
1585 goto out_unlock;
1586 }
1587
1588 /* Verify both files are either real-time or non-realtime */
1589 if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
1590 error = -EINVAL;
1591 goto out_unlock;
1592 }
1593
1594 error = xfs_qm_dqattach(ip);
1595 if (error)
1596 goto out_unlock;
1597
1598 error = xfs_qm_dqattach(tip);
1599 if (error)
1600 goto out_unlock;
1601
1602 error = xfs_swap_extent_flush(ip);
1603 if (error)
1604 goto out_unlock;
1605 error = xfs_swap_extent_flush(tip);
1606 if (error)
1607 goto out_unlock;
1608
1609 if (xfs_inode_has_cow_data(tip)) {
1610 error = xfs_reflink_cancel_cow_range(tip, 0, NULLFILEOFF, true);
1611 if (error)
1612 goto out_unlock;
1613 }
1614
1615 /*
1616 * Extent "swapping" with rmap requires a permanent reservation and
1617 * a block reservation because it's really just a remap operation
1618 * performed with log redo items!
1619 */
1620 if (xfs_sb_version_hasrmapbt(&mp->m_sb)) {
1621 int w = XFS_DATA_FORK;
1622 uint32_t ipnext = ip->i_df.if_nextents;
1623 uint32_t tipnext = tip->i_df.if_nextents;
1624
1625 /*
1626 * Conceptually this shouldn't affect the shape of either bmbt,
1627 * but since we atomically move extents one by one, we reserve
1628 * enough space to rebuild both trees.
1629 */
1630 resblks = XFS_SWAP_RMAP_SPACE_RES(mp, ipnext, w);
1631 resblks += XFS_SWAP_RMAP_SPACE_RES(mp, tipnext, w);
1632
1633 /*
1634 * If either inode straddles a bmapbt block allocation boundary,
1635 * the rmapbt algorithm triggers repeated allocs and frees as
1636 * extents are remapped. This can exhaust the block reservation
1637 * prematurely and cause shutdown. Return freed blocks to the
1638 * transaction reservation to counter this behavior.
1639 */
1640 flags |= XFS_TRANS_RES_FDBLKS;
1641 }
1642 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, flags,
1643 &tp);
1644 if (error)
1645 goto out_unlock;
1646
1647 /*
1648 * Lock and join the inodes to the tansaction so that transaction commit
1649 * or cancel will unlock the inodes from this point onwards.
1650 */
1651 xfs_lock_two_inodes(ip, XFS_ILOCK_EXCL, tip, XFS_ILOCK_EXCL);
1652 lock_flags |= XFS_ILOCK_EXCL;
1653 xfs_trans_ijoin(tp, ip, 0);
1654 xfs_trans_ijoin(tp, tip, 0);
1655
1656
1657 /* Verify all data are being swapped */
1658 if (sxp->sx_offset != 0 ||
1659 sxp->sx_length != ip->i_d.di_size ||
1660 sxp->sx_length != tip->i_d.di_size) {
1661 error = -EFAULT;
1662 goto out_trans_cancel;
1663 }
1664
1665 trace_xfs_swap_extent_before(ip, 0);
1666 trace_xfs_swap_extent_before(tip, 1);
1667
1668 /* check inode formats now that data is flushed */
1669 error = xfs_swap_extents_check_format(ip, tip);
1670 if (error) {
1671 xfs_notice(mp,
1672 "%s: inode 0x%llx format is incompatible for exchanging.",
1673 __func__, ip->i_ino);
1674 goto out_trans_cancel;
1675 }
1676
1677 /*
1678 * Compare the current change & modify times with that
1679 * passed in. If they differ, we abort this swap.
1680 * This is the mechanism used to ensure the calling
1681 * process that the file was not changed out from
1682 * under it.
1683 */
1684 if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
1685 (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
1686 (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
1687 (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
1688 error = -EBUSY;
1689 goto out_trans_cancel;
1690 }
1691
1692 /*
1693 * Note the trickiness in setting the log flags - we set the owner log
1694 * flag on the opposite inode (i.e. the inode we are setting the new
1695 * owner to be) because once we swap the forks and log that, log
1696 * recovery is going to see the fork as owned by the swapped inode,
1697 * not the pre-swapped inodes.
1698 */
1699 src_log_flags = XFS_ILOG_CORE;
1700 target_log_flags = XFS_ILOG_CORE;
1701
1702 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
1703 error = xfs_swap_extent_rmap(&tp, ip, tip);
1704 else
1705 error = xfs_swap_extent_forks(tp, ip, tip, &src_log_flags,
1706 &target_log_flags);
1707 if (error)
1708 goto out_trans_cancel;
1709
1710 /* Do we have to swap reflink flags? */
1711 if ((ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK) ^
1712 (tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK)) {
1713 f = ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
1714 ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1715 ip->i_d.di_flags2 |= tip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
1716 tip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK;
1717 tip->i_d.di_flags2 |= f & XFS_DIFLAG2_REFLINK;
1718 }
1719
1720 /* Swap the cow forks. */
1721 if (xfs_sb_version_hasreflink(&mp->m_sb)) {
1722 ASSERT(!ip->i_cowfp ||
1723 ip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS);
1724 ASSERT(!tip->i_cowfp ||
1725 tip->i_cowfp->if_format == XFS_DINODE_FMT_EXTENTS);
1726
1727 swap(ip->i_cowfp, tip->i_cowfp);
1728
1729 if (ip->i_cowfp && ip->i_cowfp->if_bytes)
1730 xfs_inode_set_cowblocks_tag(ip);
1731 else
1732 xfs_inode_clear_cowblocks_tag(ip);
1733 if (tip->i_cowfp && tip->i_cowfp->if_bytes)
1734 xfs_inode_set_cowblocks_tag(tip);
1735 else
1736 xfs_inode_clear_cowblocks_tag(tip);
1737 }
1738
1739 xfs_trans_log_inode(tp, ip, src_log_flags);
1740 xfs_trans_log_inode(tp, tip, target_log_flags);
1741
1742 /*
1743 * The extent forks have been swapped, but crc=1,rmapbt=0 filesystems
1744 * have inode number owner values in the bmbt blocks that still refer to
1745 * the old inode. Scan each bmbt to fix up the owner values with the
1746 * inode number of the current inode.
1747 */
1748 if (src_log_flags & XFS_ILOG_DOWNER) {
1749 error = xfs_swap_change_owner(&tp, ip, tip);
1750 if (error)
1751 goto out_trans_cancel;
1752 }
1753 if (target_log_flags & XFS_ILOG_DOWNER) {
1754 error = xfs_swap_change_owner(&tp, tip, ip);
1755 if (error)
1756 goto out_trans_cancel;
1757 }
1758
1759 /*
1760 * If this is a synchronous mount, make sure that the
1761 * transaction goes to disk before returning to the user.
1762 */
1763 if (mp->m_flags & XFS_MOUNT_WSYNC)
1764 xfs_trans_set_sync(tp);
1765
1766 error = xfs_trans_commit(tp);
1767
1768 trace_xfs_swap_extent_after(ip, 0);
1769 trace_xfs_swap_extent_after(tip, 1);
1770
1771out_unlock:
1772 xfs_iunlock(ip, lock_flags);
1773 xfs_iunlock(tip, lock_flags);
1774 unlock_two_nondirectories(VFS_I(ip), VFS_I(tip));
1775 return error;
1776
1777out_trans_cancel:
1778 xfs_trans_cancel(tp);
1779 goto out_unlock;
1780}