sgi-xp: fix a use after free
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / xfs / xfs_rtalloc.c
blob8f76fdff4f4688484fac811a23f97cf23f91d23a
1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_mount.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_dinode.h"
31 #include "xfs_inode.h"
32 #include "xfs_alloc.h"
33 #include "xfs_bmap.h"
34 #include "xfs_rtalloc.h"
35 #include "xfs_fsops.h"
36 #include "xfs_error.h"
37 #include "xfs_rw.h"
38 #include "xfs_inode_item.h"
39 #include "xfs_trans_space.h"
40 #include "xfs_utils.h"
41 #include "xfs_trace.h"
42 #include "xfs_buf.h"
46 * Prototypes for internal functions.
50 STATIC int xfs_rtallocate_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
51 xfs_extlen_t, xfs_buf_t **, xfs_fsblock_t *);
52 STATIC int xfs_rtany_summary(xfs_mount_t *, xfs_trans_t *, int, int,
53 xfs_rtblock_t, xfs_buf_t **, xfs_fsblock_t *, int *);
54 STATIC int xfs_rtcheck_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
55 xfs_extlen_t, int, xfs_rtblock_t *, int *);
56 STATIC int xfs_rtfind_back(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
57 xfs_rtblock_t, xfs_rtblock_t *);
58 STATIC int xfs_rtfind_forw(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
59 xfs_rtblock_t, xfs_rtblock_t *);
60 STATIC int xfs_rtget_summary( xfs_mount_t *, xfs_trans_t *, int,
61 xfs_rtblock_t, xfs_buf_t **, xfs_fsblock_t *, xfs_suminfo_t *);
62 STATIC int xfs_rtmodify_range(xfs_mount_t *, xfs_trans_t *, xfs_rtblock_t,
63 xfs_extlen_t, int);
64 STATIC int xfs_rtmodify_summary(xfs_mount_t *, xfs_trans_t *, int,
65 xfs_rtblock_t, int, xfs_buf_t **, xfs_fsblock_t *);
68 * Internal functions.
72 * Allocate space to the bitmap or summary file, and zero it, for growfs.
74 STATIC int /* error */
75 xfs_growfs_rt_alloc(
76 xfs_mount_t *mp, /* file system mount point */
77 xfs_extlen_t oblocks, /* old count of blocks */
78 xfs_extlen_t nblocks, /* new count of blocks */
79 xfs_inode_t *ip) /* inode (bitmap/summary) */
81 xfs_fileoff_t bno; /* block number in file */
82 xfs_buf_t *bp; /* temporary buffer for zeroing */
83 int committed; /* transaction committed flag */
84 xfs_daddr_t d; /* disk block address */
85 int error; /* error return value */
86 xfs_fsblock_t firstblock; /* first block allocated in xaction */
87 xfs_bmap_free_t flist; /* list of freed blocks */
88 xfs_fsblock_t fsbno; /* filesystem block for bno */
89 xfs_bmbt_irec_t map; /* block map output */
90 int nmap; /* number of block maps */
91 int resblks; /* space reservation */
94 * Allocate space to the file, as necessary.
96 while (oblocks < nblocks) {
97 int cancelflags = 0;
98 xfs_trans_t *tp;
100 tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ALLOC);
101 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
103 * Reserve space & log for one extent added to the file.
105 if ((error = xfs_trans_reserve(tp, resblks,
106 XFS_GROWRTALLOC_LOG_RES(mp), 0,
107 XFS_TRANS_PERM_LOG_RES,
108 XFS_DEFAULT_PERM_LOG_COUNT)))
109 goto error_cancel;
110 cancelflags = XFS_TRANS_RELEASE_LOG_RES;
112 * Lock the inode.
114 xfs_ilock(ip, XFS_ILOCK_EXCL);
115 xfs_trans_ijoin_ref(tp, ip, XFS_ILOCK_EXCL);
117 xfs_bmap_init(&flist, &firstblock);
119 * Allocate blocks to the bitmap file.
121 nmap = 1;
122 cancelflags |= XFS_TRANS_ABORT;
123 error = xfs_bmapi(tp, ip, oblocks, nblocks - oblocks,
124 XFS_BMAPI_WRITE | XFS_BMAPI_METADATA, &firstblock,
125 resblks, &map, &nmap, &flist);
126 if (!error && nmap < 1)
127 error = XFS_ERROR(ENOSPC);
128 if (error)
129 goto error_cancel;
131 * Free any blocks freed up in the transaction, then commit.
133 error = xfs_bmap_finish(&tp, &flist, &committed);
134 if (error)
135 goto error_cancel;
136 error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
137 if (error)
138 goto error;
140 * Now we need to clear the allocated blocks.
141 * Do this one block per transaction, to keep it simple.
143 cancelflags = 0;
144 for (bno = map.br_startoff, fsbno = map.br_startblock;
145 bno < map.br_startoff + map.br_blockcount;
146 bno++, fsbno++) {
147 tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_ZERO);
149 * Reserve log for one block zeroing.
151 if ((error = xfs_trans_reserve(tp, 0,
152 XFS_GROWRTZERO_LOG_RES(mp), 0, 0, 0)))
153 goto error_cancel;
155 * Lock the bitmap inode.
157 xfs_ilock(ip, XFS_ILOCK_EXCL);
158 xfs_trans_ijoin_ref(tp, ip, XFS_ILOCK_EXCL);
160 * Get a buffer for the block.
162 d = XFS_FSB_TO_DADDR(mp, fsbno);
163 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
164 mp->m_bsize, 0);
165 if (bp == NULL) {
166 error = XFS_ERROR(EIO);
167 error_cancel:
168 xfs_trans_cancel(tp, cancelflags);
169 goto error;
171 memset(XFS_BUF_PTR(bp), 0, mp->m_sb.sb_blocksize);
172 xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
174 * Commit the transaction.
176 error = xfs_trans_commit(tp, 0);
177 if (error)
178 goto error;
181 * Go on to the next extent, if any.
183 oblocks = map.br_startoff + map.br_blockcount;
185 return 0;
186 error:
187 return error;
191 * Attempt to allocate an extent minlen<=len<=maxlen starting from
192 * bitmap block bbno. If we don't get maxlen then use prod to trim
193 * the length, if given. Returns error; returns starting block in *rtblock.
194 * The lengths are all in rtextents.
196 STATIC int /* error */
197 xfs_rtallocate_extent_block(
198 xfs_mount_t *mp, /* file system mount point */
199 xfs_trans_t *tp, /* transaction pointer */
200 xfs_rtblock_t bbno, /* bitmap block number */
201 xfs_extlen_t minlen, /* minimum length to allocate */
202 xfs_extlen_t maxlen, /* maximum length to allocate */
203 xfs_extlen_t *len, /* out: actual length allocated */
204 xfs_rtblock_t *nextp, /* out: next block to try */
205 xfs_buf_t **rbpp, /* in/out: summary block buffer */
206 xfs_fsblock_t *rsb, /* in/out: summary block number */
207 xfs_extlen_t prod, /* extent product factor */
208 xfs_rtblock_t *rtblock) /* out: start block allocated */
210 xfs_rtblock_t besti; /* best rtblock found so far */
211 xfs_rtblock_t bestlen; /* best length found so far */
212 xfs_rtblock_t end; /* last rtblock in chunk */
213 int error; /* error value */
214 xfs_rtblock_t i; /* current rtblock trying */
215 xfs_rtblock_t next; /* next rtblock to try */
216 int stat; /* status from internal calls */
219 * Loop over all the extents starting in this bitmap block,
220 * looking for one that's long enough.
222 for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
223 end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
224 i <= end;
225 i++) {
227 * See if there's a free extent of maxlen starting at i.
228 * If it's not so then next will contain the first non-free.
230 error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
231 if (error) {
232 return error;
234 if (stat) {
236 * i for maxlen is all free, allocate and return that.
238 error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
239 rsb);
240 if (error) {
241 return error;
243 *len = maxlen;
244 *rtblock = i;
245 return 0;
248 * In the case where we have a variable-sized allocation
249 * request, figure out how big this free piece is,
250 * and if it's big enough for the minimum, and the best
251 * so far, remember it.
253 if (minlen < maxlen) {
254 xfs_rtblock_t thislen; /* this extent size */
256 thislen = next - i;
257 if (thislen >= minlen && thislen > bestlen) {
258 besti = i;
259 bestlen = thislen;
263 * If not done yet, find the start of the next free space.
265 if (next < end) {
266 error = xfs_rtfind_forw(mp, tp, next, end, &i);
267 if (error) {
268 return error;
270 } else
271 break;
274 * Searched the whole thing & didn't find a maxlen free extent.
276 if (minlen < maxlen && besti != -1) {
277 xfs_extlen_t p; /* amount to trim length by */
280 * If size should be a multiple of prod, make that so.
282 if (prod > 1 && (p = do_mod(bestlen, prod)))
283 bestlen -= p;
285 * Allocate besti for bestlen & return that.
287 error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
288 if (error) {
289 return error;
291 *len = bestlen;
292 *rtblock = besti;
293 return 0;
296 * Allocation failed. Set *nextp to the next block to try.
298 *nextp = next;
299 *rtblock = NULLRTBLOCK;
300 return 0;
304 * Allocate an extent of length minlen<=len<=maxlen, starting at block
305 * bno. If we don't get maxlen then use prod to trim the length, if given.
306 * Returns error; returns starting block in *rtblock.
307 * The lengths are all in rtextents.
309 STATIC int /* error */
310 xfs_rtallocate_extent_exact(
311 xfs_mount_t *mp, /* file system mount point */
312 xfs_trans_t *tp, /* transaction pointer */
313 xfs_rtblock_t bno, /* starting block number to allocate */
314 xfs_extlen_t minlen, /* minimum length to allocate */
315 xfs_extlen_t maxlen, /* maximum length to allocate */
316 xfs_extlen_t *len, /* out: actual length allocated */
317 xfs_buf_t **rbpp, /* in/out: summary block buffer */
318 xfs_fsblock_t *rsb, /* in/out: summary block number */
319 xfs_extlen_t prod, /* extent product factor */
320 xfs_rtblock_t *rtblock) /* out: start block allocated */
322 int error; /* error value */
323 xfs_extlen_t i; /* extent length trimmed due to prod */
324 int isfree; /* extent is free */
325 xfs_rtblock_t next; /* next block to try (dummy) */
327 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
329 * Check if the range in question (for maxlen) is free.
331 error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
332 if (error) {
333 return error;
335 if (isfree) {
337 * If it is, allocate it and return success.
339 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
340 if (error) {
341 return error;
343 *len = maxlen;
344 *rtblock = bno;
345 return 0;
348 * If not, allocate what there is, if it's at least minlen.
350 maxlen = next - bno;
351 if (maxlen < minlen) {
353 * Failed, return failure status.
355 *rtblock = NULLRTBLOCK;
356 return 0;
359 * Trim off tail of extent, if prod is specified.
361 if (prod > 1 && (i = maxlen % prod)) {
362 maxlen -= i;
363 if (maxlen < minlen) {
365 * Now we can't do it, return failure status.
367 *rtblock = NULLRTBLOCK;
368 return 0;
372 * Allocate what we can and return it.
374 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
375 if (error) {
376 return error;
378 *len = maxlen;
379 *rtblock = bno;
380 return 0;
384 * Allocate an extent of length minlen<=len<=maxlen, starting as near
385 * to bno as possible. If we don't get maxlen then use prod to trim
386 * the length, if given. The lengths are all in rtextents.
388 STATIC int /* error */
389 xfs_rtallocate_extent_near(
390 xfs_mount_t *mp, /* file system mount point */
391 xfs_trans_t *tp, /* transaction pointer */
392 xfs_rtblock_t bno, /* starting block number to allocate */
393 xfs_extlen_t minlen, /* minimum length to allocate */
394 xfs_extlen_t maxlen, /* maximum length to allocate */
395 xfs_extlen_t *len, /* out: actual length allocated */
396 xfs_buf_t **rbpp, /* in/out: summary block buffer */
397 xfs_fsblock_t *rsb, /* in/out: summary block number */
398 xfs_extlen_t prod, /* extent product factor */
399 xfs_rtblock_t *rtblock) /* out: start block allocated */
401 int any; /* any useful extents from summary */
402 xfs_rtblock_t bbno; /* bitmap block number */
403 int error; /* error value */
404 int i; /* bitmap block offset (loop control) */
405 int j; /* secondary loop control */
406 int log2len; /* log2 of minlen */
407 xfs_rtblock_t n; /* next block to try */
408 xfs_rtblock_t r; /* result block */
410 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
412 * If the block number given is off the end, silently set it to
413 * the last block.
415 if (bno >= mp->m_sb.sb_rextents)
416 bno = mp->m_sb.sb_rextents - 1;
418 * Try the exact allocation first.
420 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
421 rbpp, rsb, prod, &r);
422 if (error) {
423 return error;
426 * If the exact allocation worked, return that.
428 if (r != NULLRTBLOCK) {
429 *rtblock = r;
430 return 0;
432 bbno = XFS_BITTOBLOCK(mp, bno);
433 i = 0;
434 ASSERT(minlen != 0);
435 log2len = xfs_highbit32(minlen);
437 * Loop over all bitmap blocks (bbno + i is current block).
439 for (;;) {
441 * Get summary information of extents of all useful levels
442 * starting in this bitmap block.
444 error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
445 bbno + i, rbpp, rsb, &any);
446 if (error) {
447 return error;
450 * If there are any useful extents starting here, try
451 * allocating one.
453 if (any) {
455 * On the positive side of the starting location.
457 if (i >= 0) {
459 * Try to allocate an extent starting in
460 * this block.
462 error = xfs_rtallocate_extent_block(mp, tp,
463 bbno + i, minlen, maxlen, len, &n, rbpp,
464 rsb, prod, &r);
465 if (error) {
466 return error;
469 * If it worked, return it.
471 if (r != NULLRTBLOCK) {
472 *rtblock = r;
473 return 0;
477 * On the negative side of the starting location.
479 else { /* i < 0 */
481 * Loop backwards through the bitmap blocks from
482 * the starting point-1 up to where we are now.
483 * There should be an extent which ends in this
484 * bitmap block and is long enough.
486 for (j = -1; j > i; j--) {
488 * Grab the summary information for
489 * this bitmap block.
491 error = xfs_rtany_summary(mp, tp,
492 log2len, mp->m_rsumlevels - 1,
493 bbno + j, rbpp, rsb, &any);
494 if (error) {
495 return error;
498 * If there's no extent given in the
499 * summary that means the extent we
500 * found must carry over from an
501 * earlier block. If there is an
502 * extent given, we've already tried
503 * that allocation, don't do it again.
505 if (any)
506 continue;
507 error = xfs_rtallocate_extent_block(mp,
508 tp, bbno + j, minlen, maxlen,
509 len, &n, rbpp, rsb, prod, &r);
510 if (error) {
511 return error;
514 * If it works, return the extent.
516 if (r != NULLRTBLOCK) {
517 *rtblock = r;
518 return 0;
522 * There weren't intervening bitmap blocks
523 * with a long enough extent, or the
524 * allocation didn't work for some reason
525 * (i.e. it's a little * too short).
526 * Try to allocate from the summary block
527 * that we found.
529 error = xfs_rtallocate_extent_block(mp, tp,
530 bbno + i, minlen, maxlen, len, &n, rbpp,
531 rsb, prod, &r);
532 if (error) {
533 return error;
536 * If it works, return the extent.
538 if (r != NULLRTBLOCK) {
539 *rtblock = r;
540 return 0;
545 * Loop control. If we were on the positive side, and there's
546 * still more blocks on the negative side, go there.
548 if (i > 0 && (int)bbno - i >= 0)
549 i = -i;
551 * If positive, and no more negative, but there are more
552 * positive, go there.
554 else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
555 i++;
557 * If negative or 0 (just started), and there are positive
558 * blocks to go, go there. The 0 case moves to block 1.
560 else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
561 i = 1 - i;
563 * If negative or 0 and there are more negative blocks,
564 * go there.
566 else if (i <= 0 && (int)bbno + i > 0)
567 i--;
569 * Must be done. Return failure.
571 else
572 break;
574 *rtblock = NULLRTBLOCK;
575 return 0;
579 * Allocate an extent of length minlen<=len<=maxlen, with no position
580 * specified. If we don't get maxlen then use prod to trim
581 * the length, if given. The lengths are all in rtextents.
583 STATIC int /* error */
584 xfs_rtallocate_extent_size(
585 xfs_mount_t *mp, /* file system mount point */
586 xfs_trans_t *tp, /* transaction pointer */
587 xfs_extlen_t minlen, /* minimum length to allocate */
588 xfs_extlen_t maxlen, /* maximum length to allocate */
589 xfs_extlen_t *len, /* out: actual length allocated */
590 xfs_buf_t **rbpp, /* in/out: summary block buffer */
591 xfs_fsblock_t *rsb, /* in/out: summary block number */
592 xfs_extlen_t prod, /* extent product factor */
593 xfs_rtblock_t *rtblock) /* out: start block allocated */
595 int error; /* error value */
596 int i; /* bitmap block number */
597 int l; /* level number (loop control) */
598 xfs_rtblock_t n; /* next block to be tried */
599 xfs_rtblock_t r; /* result block number */
600 xfs_suminfo_t sum; /* summary information for extents */
602 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
603 ASSERT(maxlen != 0);
606 * Loop over all the levels starting with maxlen.
607 * At each level, look at all the bitmap blocks, to see if there
608 * are extents starting there that are long enough (>= maxlen).
609 * Note, only on the initial level can the allocation fail if
610 * the summary says there's an extent.
612 for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
614 * Loop over all the bitmap blocks.
616 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
618 * Get the summary for this level/block.
620 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
621 &sum);
622 if (error) {
623 return error;
626 * Nothing there, on to the next block.
628 if (!sum)
629 continue;
631 * Try allocating the extent.
633 error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
634 maxlen, len, &n, rbpp, rsb, prod, &r);
635 if (error) {
636 return error;
639 * If it worked, return that.
641 if (r != NULLRTBLOCK) {
642 *rtblock = r;
643 return 0;
646 * If the "next block to try" returned from the
647 * allocator is beyond the next bitmap block,
648 * skip to that bitmap block.
650 if (XFS_BITTOBLOCK(mp, n) > i + 1)
651 i = XFS_BITTOBLOCK(mp, n) - 1;
655 * Didn't find any maxlen blocks. Try smaller ones, unless
656 * we're asking for a fixed size extent.
658 if (minlen > --maxlen) {
659 *rtblock = NULLRTBLOCK;
660 return 0;
662 ASSERT(minlen != 0);
663 ASSERT(maxlen != 0);
666 * Loop over sizes, from maxlen down to minlen.
667 * This time, when we do the allocations, allow smaller ones
668 * to succeed.
670 for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
672 * Loop over all the bitmap blocks, try an allocation
673 * starting in that block.
675 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
677 * Get the summary information for this level/block.
679 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
680 &sum);
681 if (error) {
682 return error;
685 * If nothing there, go on to next.
687 if (!sum)
688 continue;
690 * Try the allocation. Make sure the specified
691 * minlen/maxlen are in the possible range for
692 * this summary level.
694 error = xfs_rtallocate_extent_block(mp, tp, i,
695 XFS_RTMAX(minlen, 1 << l),
696 XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
697 len, &n, rbpp, rsb, prod, &r);
698 if (error) {
699 return error;
702 * If it worked, return that extent.
704 if (r != NULLRTBLOCK) {
705 *rtblock = r;
706 return 0;
709 * If the "next block to try" returned from the
710 * allocator is beyond the next bitmap block,
711 * skip to that bitmap block.
713 if (XFS_BITTOBLOCK(mp, n) > i + 1)
714 i = XFS_BITTOBLOCK(mp, n) - 1;
718 * Got nothing, return failure.
720 *rtblock = NULLRTBLOCK;
721 return 0;
725 * Mark an extent specified by start and len allocated.
726 * Updates all the summary information as well as the bitmap.
728 STATIC int /* error */
729 xfs_rtallocate_range(
730 xfs_mount_t *mp, /* file system mount point */
731 xfs_trans_t *tp, /* transaction pointer */
732 xfs_rtblock_t start, /* start block to allocate */
733 xfs_extlen_t len, /* length to allocate */
734 xfs_buf_t **rbpp, /* in/out: summary block buffer */
735 xfs_fsblock_t *rsb) /* in/out: summary block number */
737 xfs_rtblock_t end; /* end of the allocated extent */
738 int error; /* error value */
739 xfs_rtblock_t postblock; /* first block allocated > end */
740 xfs_rtblock_t preblock; /* first block allocated < start */
742 end = start + len - 1;
744 * Assume we're allocating out of the middle of a free extent.
745 * We need to find the beginning and end of the extent so we can
746 * properly update the summary.
748 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
749 if (error) {
750 return error;
753 * Find the next allocated block (end of free extent).
755 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
756 &postblock);
757 if (error) {
758 return error;
761 * Decrement the summary information corresponding to the entire
762 * (old) free extent.
764 error = xfs_rtmodify_summary(mp, tp,
765 XFS_RTBLOCKLOG(postblock + 1 - preblock),
766 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
767 if (error) {
768 return error;
771 * If there are blocks not being allocated at the front of the
772 * old extent, add summary data for them to be free.
774 if (preblock < start) {
775 error = xfs_rtmodify_summary(mp, tp,
776 XFS_RTBLOCKLOG(start - preblock),
777 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
778 if (error) {
779 return error;
783 * If there are blocks not being allocated at the end of the
784 * old extent, add summary data for them to be free.
786 if (postblock > end) {
787 error = xfs_rtmodify_summary(mp, tp,
788 XFS_RTBLOCKLOG(postblock - end),
789 XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
790 if (error) {
791 return error;
795 * Modify the bitmap to mark this extent allocated.
797 error = xfs_rtmodify_range(mp, tp, start, len, 0);
798 return error;
802 * Return whether there are any free extents in the size range given
803 * by low and high, for the bitmap block bbno.
805 STATIC int /* error */
806 xfs_rtany_summary(
807 xfs_mount_t *mp, /* file system mount structure */
808 xfs_trans_t *tp, /* transaction pointer */
809 int low, /* low log2 extent size */
810 int high, /* high log2 extent size */
811 xfs_rtblock_t bbno, /* bitmap block number */
812 xfs_buf_t **rbpp, /* in/out: summary block buffer */
813 xfs_fsblock_t *rsb, /* in/out: summary block number */
814 int *stat) /* out: any good extents here? */
816 int error; /* error value */
817 int log; /* loop counter, log2 of ext. size */
818 xfs_suminfo_t sum; /* summary data */
821 * Loop over logs of extent sizes. Order is irrelevant.
823 for (log = low; log <= high; log++) {
825 * Get one summary datum.
827 error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
828 if (error) {
829 return error;
832 * If there are any, return success.
834 if (sum) {
835 *stat = 1;
836 return 0;
840 * Found nothing, return failure.
842 *stat = 0;
843 return 0;
847 * Get a buffer for the bitmap or summary file block specified.
848 * The buffer is returned read and locked.
850 STATIC int /* error */
851 xfs_rtbuf_get(
852 xfs_mount_t *mp, /* file system mount structure */
853 xfs_trans_t *tp, /* transaction pointer */
854 xfs_rtblock_t block, /* block number in bitmap or summary */
855 int issum, /* is summary not bitmap */
856 xfs_buf_t **bpp) /* output: buffer for the block */
858 xfs_buf_t *bp; /* block buffer, result */
859 xfs_daddr_t d; /* disk addr of block */
860 int error; /* error value */
861 xfs_fsblock_t fsb; /* fs block number for block */
862 xfs_inode_t *ip; /* bitmap or summary inode */
864 ip = issum ? mp->m_rsumip : mp->m_rbmip;
866 * Map from the file offset (block) and inode number to the
867 * file system block.
869 error = xfs_bmapi_single(tp, ip, XFS_DATA_FORK, &fsb, block);
870 if (error) {
871 return error;
873 ASSERT(fsb != NULLFSBLOCK);
875 * Convert to disk address for buffer cache.
877 d = XFS_FSB_TO_DADDR(mp, fsb);
879 * Read the buffer.
881 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, d,
882 mp->m_bsize, 0, &bp);
883 if (error) {
884 return error;
886 ASSERT(bp && !XFS_BUF_GETERROR(bp));
887 *bpp = bp;
888 return 0;
891 #ifdef DEBUG
893 * Check that the given extent (block range) is allocated already.
895 STATIC int /* error */
896 xfs_rtcheck_alloc_range(
897 xfs_mount_t *mp, /* file system mount point */
898 xfs_trans_t *tp, /* transaction pointer */
899 xfs_rtblock_t bno, /* starting block number of extent */
900 xfs_extlen_t len, /* length of extent */
901 int *stat) /* out: 1 for allocated, 0 for not */
903 xfs_rtblock_t new; /* dummy for xfs_rtcheck_range */
905 return xfs_rtcheck_range(mp, tp, bno, len, 0, &new, stat);
907 #endif
910 * Check that the given range is either all allocated (val = 0) or
911 * all free (val = 1).
913 STATIC int /* error */
914 xfs_rtcheck_range(
915 xfs_mount_t *mp, /* file system mount point */
916 xfs_trans_t *tp, /* transaction pointer */
917 xfs_rtblock_t start, /* starting block number of extent */
918 xfs_extlen_t len, /* length of extent */
919 int val, /* 1 for free, 0 for allocated */
920 xfs_rtblock_t *new, /* out: first block not matching */
921 int *stat) /* out: 1 for matches, 0 for not */
923 xfs_rtword_t *b; /* current word in buffer */
924 int bit; /* bit number in the word */
925 xfs_rtblock_t block; /* bitmap block number */
926 xfs_buf_t *bp; /* buf for the block */
927 xfs_rtword_t *bufp; /* starting word in buffer */
928 int error; /* error value */
929 xfs_rtblock_t i; /* current bit number rel. to start */
930 xfs_rtblock_t lastbit; /* last useful bit in word */
931 xfs_rtword_t mask; /* mask of relevant bits for value */
932 xfs_rtword_t wdiff; /* difference from wanted value */
933 int word; /* word number in the buffer */
936 * Compute starting bitmap block number
938 block = XFS_BITTOBLOCK(mp, start);
940 * Read the bitmap block.
942 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
943 if (error) {
944 return error;
946 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
948 * Compute the starting word's address, and starting bit.
950 word = XFS_BITTOWORD(mp, start);
951 b = &bufp[word];
952 bit = (int)(start & (XFS_NBWORD - 1));
954 * 0 (allocated) => all zero's; 1 (free) => all one's.
956 val = -val;
958 * If not starting on a word boundary, deal with the first
959 * (partial) word.
961 if (bit) {
963 * Compute first bit not examined.
965 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
967 * Mask of relevant bits.
969 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
971 * Compute difference between actual and desired value.
973 if ((wdiff = (*b ^ val) & mask)) {
975 * Different, compute first wrong bit and return.
977 xfs_trans_brelse(tp, bp);
978 i = XFS_RTLOBIT(wdiff) - bit;
979 *new = start + i;
980 *stat = 0;
981 return 0;
983 i = lastbit - bit;
985 * Go on to next block if that's where the next word is
986 * and we need the next word.
988 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
990 * If done with this block, get the next one.
992 xfs_trans_brelse(tp, bp);
993 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
994 if (error) {
995 return error;
997 b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
998 word = 0;
999 } else {
1001 * Go on to the next word in the buffer.
1003 b++;
1005 } else {
1007 * Starting on a word boundary, no partial word.
1009 i = 0;
1012 * Loop over whole words in buffers. When we use up one buffer
1013 * we move on to the next one.
1015 while (len - i >= XFS_NBWORD) {
1017 * Compute difference between actual and desired value.
1019 if ((wdiff = *b ^ val)) {
1021 * Different, compute first wrong bit and return.
1023 xfs_trans_brelse(tp, bp);
1024 i += XFS_RTLOBIT(wdiff);
1025 *new = start + i;
1026 *stat = 0;
1027 return 0;
1029 i += XFS_NBWORD;
1031 * Go on to next block if that's where the next word is
1032 * and we need the next word.
1034 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
1036 * If done with this block, get the next one.
1038 xfs_trans_brelse(tp, bp);
1039 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
1040 if (error) {
1041 return error;
1043 b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1044 word = 0;
1045 } else {
1047 * Go on to the next word in the buffer.
1049 b++;
1053 * If not ending on a word boundary, deal with the last
1054 * (partial) word.
1056 if ((lastbit = len - i)) {
1058 * Mask of relevant bits.
1060 mask = ((xfs_rtword_t)1 << lastbit) - 1;
1062 * Compute difference between actual and desired value.
1064 if ((wdiff = (*b ^ val) & mask)) {
1066 * Different, compute first wrong bit and return.
1068 xfs_trans_brelse(tp, bp);
1069 i += XFS_RTLOBIT(wdiff);
1070 *new = start + i;
1071 *stat = 0;
1072 return 0;
1073 } else
1074 i = len;
1077 * Successful, return.
1079 xfs_trans_brelse(tp, bp);
1080 *new = start + i;
1081 *stat = 1;
1082 return 0;
1086 * Copy and transform the summary file, given the old and new
1087 * parameters in the mount structures.
1089 STATIC int /* error */
1090 xfs_rtcopy_summary(
1091 xfs_mount_t *omp, /* old file system mount point */
1092 xfs_mount_t *nmp, /* new file system mount point */
1093 xfs_trans_t *tp) /* transaction pointer */
1095 xfs_rtblock_t bbno; /* bitmap block number */
1096 xfs_buf_t *bp; /* summary buffer */
1097 int error; /* error return value */
1098 int log; /* summary level number (log length) */
1099 xfs_suminfo_t sum; /* summary data */
1100 xfs_fsblock_t sumbno; /* summary block number */
1102 bp = NULL;
1103 for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
1104 for (bbno = omp->m_sb.sb_rbmblocks - 1;
1105 (xfs_srtblock_t)bbno >= 0;
1106 bbno--) {
1107 error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
1108 &sumbno, &sum);
1109 if (error)
1110 return error;
1111 if (sum == 0)
1112 continue;
1113 error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
1114 &bp, &sumbno);
1115 if (error)
1116 return error;
1117 error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
1118 &bp, &sumbno);
1119 if (error)
1120 return error;
1121 ASSERT(sum > 0);
1124 return 0;
1128 * Searching backward from start to limit, find the first block whose
1129 * allocated/free state is different from start's.
1131 STATIC int /* error */
1132 xfs_rtfind_back(
1133 xfs_mount_t *mp, /* file system mount point */
1134 xfs_trans_t *tp, /* transaction pointer */
1135 xfs_rtblock_t start, /* starting block to look at */
1136 xfs_rtblock_t limit, /* last block to look at */
1137 xfs_rtblock_t *rtblock) /* out: start block found */
1139 xfs_rtword_t *b; /* current word in buffer */
1140 int bit; /* bit number in the word */
1141 xfs_rtblock_t block; /* bitmap block number */
1142 xfs_buf_t *bp; /* buf for the block */
1143 xfs_rtword_t *bufp; /* starting word in buffer */
1144 int error; /* error value */
1145 xfs_rtblock_t firstbit; /* first useful bit in the word */
1146 xfs_rtblock_t i; /* current bit number rel. to start */
1147 xfs_rtblock_t len; /* length of inspected area */
1148 xfs_rtword_t mask; /* mask of relevant bits for value */
1149 xfs_rtword_t want; /* mask for "good" values */
1150 xfs_rtword_t wdiff; /* difference from wanted value */
1151 int word; /* word number in the buffer */
1154 * Compute and read in starting bitmap block for starting block.
1156 block = XFS_BITTOBLOCK(mp, start);
1157 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
1158 if (error) {
1159 return error;
1161 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1163 * Get the first word's index & point to it.
1165 word = XFS_BITTOWORD(mp, start);
1166 b = &bufp[word];
1167 bit = (int)(start & (XFS_NBWORD - 1));
1168 len = start - limit + 1;
1170 * Compute match value, based on the bit at start: if 1 (free)
1171 * then all-ones, else all-zeroes.
1173 want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
1175 * If the starting position is not word-aligned, deal with the
1176 * partial word.
1178 if (bit < XFS_NBWORD - 1) {
1180 * Calculate first (leftmost) bit number to look at,
1181 * and mask for all the relevant bits in this word.
1183 firstbit = XFS_RTMAX((xfs_srtblock_t)(bit - len + 1), 0);
1184 mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
1185 firstbit;
1187 * Calculate the difference between the value there
1188 * and what we're looking for.
1190 if ((wdiff = (*b ^ want) & mask)) {
1192 * Different. Mark where we are and return.
1194 xfs_trans_brelse(tp, bp);
1195 i = bit - XFS_RTHIBIT(wdiff);
1196 *rtblock = start - i + 1;
1197 return 0;
1199 i = bit - firstbit + 1;
1201 * Go on to previous block if that's where the previous word is
1202 * and we need the previous word.
1204 if (--word == -1 && i < len) {
1206 * If done with this block, get the previous one.
1208 xfs_trans_brelse(tp, bp);
1209 error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
1210 if (error) {
1211 return error;
1213 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1214 word = XFS_BLOCKWMASK(mp);
1215 b = &bufp[word];
1216 } else {
1218 * Go on to the previous word in the buffer.
1220 b--;
1222 } else {
1224 * Starting on a word boundary, no partial word.
1226 i = 0;
1229 * Loop over whole words in buffers. When we use up one buffer
1230 * we move on to the previous one.
1232 while (len - i >= XFS_NBWORD) {
1234 * Compute difference between actual and desired value.
1236 if ((wdiff = *b ^ want)) {
1238 * Different, mark where we are and return.
1240 xfs_trans_brelse(tp, bp);
1241 i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
1242 *rtblock = start - i + 1;
1243 return 0;
1245 i += XFS_NBWORD;
1247 * Go on to previous block if that's where the previous word is
1248 * and we need the previous word.
1250 if (--word == -1 && i < len) {
1252 * If done with this block, get the previous one.
1254 xfs_trans_brelse(tp, bp);
1255 error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
1256 if (error) {
1257 return error;
1259 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1260 word = XFS_BLOCKWMASK(mp);
1261 b = &bufp[word];
1262 } else {
1264 * Go on to the previous word in the buffer.
1266 b--;
1270 * If not ending on a word boundary, deal with the last
1271 * (partial) word.
1273 if (len - i) {
1275 * Calculate first (leftmost) bit number to look at,
1276 * and mask for all the relevant bits in this word.
1278 firstbit = XFS_NBWORD - (len - i);
1279 mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
1281 * Compute difference between actual and desired value.
1283 if ((wdiff = (*b ^ want) & mask)) {
1285 * Different, mark where we are and return.
1287 xfs_trans_brelse(tp, bp);
1288 i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
1289 *rtblock = start - i + 1;
1290 return 0;
1291 } else
1292 i = len;
1295 * No match, return that we scanned the whole area.
1297 xfs_trans_brelse(tp, bp);
1298 *rtblock = start - i + 1;
1299 return 0;
1303 * Searching forward from start to limit, find the first block whose
1304 * allocated/free state is different from start's.
1306 STATIC int /* error */
1307 xfs_rtfind_forw(
1308 xfs_mount_t *mp, /* file system mount point */
1309 xfs_trans_t *tp, /* transaction pointer */
1310 xfs_rtblock_t start, /* starting block to look at */
1311 xfs_rtblock_t limit, /* last block to look at */
1312 xfs_rtblock_t *rtblock) /* out: start block found */
1314 xfs_rtword_t *b; /* current word in buffer */
1315 int bit; /* bit number in the word */
1316 xfs_rtblock_t block; /* bitmap block number */
1317 xfs_buf_t *bp; /* buf for the block */
1318 xfs_rtword_t *bufp; /* starting word in buffer */
1319 int error; /* error value */
1320 xfs_rtblock_t i; /* current bit number rel. to start */
1321 xfs_rtblock_t lastbit; /* last useful bit in the word */
1322 xfs_rtblock_t len; /* length of inspected area */
1323 xfs_rtword_t mask; /* mask of relevant bits for value */
1324 xfs_rtword_t want; /* mask for "good" values */
1325 xfs_rtword_t wdiff; /* difference from wanted value */
1326 int word; /* word number in the buffer */
1329 * Compute and read in starting bitmap block for starting block.
1331 block = XFS_BITTOBLOCK(mp, start);
1332 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
1333 if (error) {
1334 return error;
1336 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1338 * Get the first word's index & point to it.
1340 word = XFS_BITTOWORD(mp, start);
1341 b = &bufp[word];
1342 bit = (int)(start & (XFS_NBWORD - 1));
1343 len = limit - start + 1;
1345 * Compute match value, based on the bit at start: if 1 (free)
1346 * then all-ones, else all-zeroes.
1348 want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
1350 * If the starting position is not word-aligned, deal with the
1351 * partial word.
1353 if (bit) {
1355 * Calculate last (rightmost) bit number to look at,
1356 * and mask for all the relevant bits in this word.
1358 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
1359 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
1361 * Calculate the difference between the value there
1362 * and what we're looking for.
1364 if ((wdiff = (*b ^ want) & mask)) {
1366 * Different. Mark where we are and return.
1368 xfs_trans_brelse(tp, bp);
1369 i = XFS_RTLOBIT(wdiff) - bit;
1370 *rtblock = start + i - 1;
1371 return 0;
1373 i = lastbit - bit;
1375 * Go on to next block if that's where the next word is
1376 * and we need the next word.
1378 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
1380 * If done with this block, get the previous one.
1382 xfs_trans_brelse(tp, bp);
1383 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
1384 if (error) {
1385 return error;
1387 b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1388 word = 0;
1389 } else {
1391 * Go on to the previous word in the buffer.
1393 b++;
1395 } else {
1397 * Starting on a word boundary, no partial word.
1399 i = 0;
1402 * Loop over whole words in buffers. When we use up one buffer
1403 * we move on to the next one.
1405 while (len - i >= XFS_NBWORD) {
1407 * Compute difference between actual and desired value.
1409 if ((wdiff = *b ^ want)) {
1411 * Different, mark where we are and return.
1413 xfs_trans_brelse(tp, bp);
1414 i += XFS_RTLOBIT(wdiff);
1415 *rtblock = start + i - 1;
1416 return 0;
1418 i += XFS_NBWORD;
1420 * Go on to next block if that's where the next word is
1421 * and we need the next word.
1423 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
1425 * If done with this block, get the next one.
1427 xfs_trans_brelse(tp, bp);
1428 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
1429 if (error) {
1430 return error;
1432 b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1433 word = 0;
1434 } else {
1436 * Go on to the next word in the buffer.
1438 b++;
1442 * If not ending on a word boundary, deal with the last
1443 * (partial) word.
1445 if ((lastbit = len - i)) {
1447 * Calculate mask for all the relevant bits in this word.
1449 mask = ((xfs_rtword_t)1 << lastbit) - 1;
1451 * Compute difference between actual and desired value.
1453 if ((wdiff = (*b ^ want) & mask)) {
1455 * Different, mark where we are and return.
1457 xfs_trans_brelse(tp, bp);
1458 i += XFS_RTLOBIT(wdiff);
1459 *rtblock = start + i - 1;
1460 return 0;
1461 } else
1462 i = len;
1465 * No match, return that we scanned the whole area.
1467 xfs_trans_brelse(tp, bp);
1468 *rtblock = start + i - 1;
1469 return 0;
1473 * Mark an extent specified by start and len freed.
1474 * Updates all the summary information as well as the bitmap.
1476 STATIC int /* error */
1477 xfs_rtfree_range(
1478 xfs_mount_t *mp, /* file system mount point */
1479 xfs_trans_t *tp, /* transaction pointer */
1480 xfs_rtblock_t start, /* starting block to free */
1481 xfs_extlen_t len, /* length to free */
1482 xfs_buf_t **rbpp, /* in/out: summary block buffer */
1483 xfs_fsblock_t *rsb) /* in/out: summary block number */
1485 xfs_rtblock_t end; /* end of the freed extent */
1486 int error; /* error value */
1487 xfs_rtblock_t postblock; /* first block freed > end */
1488 xfs_rtblock_t preblock; /* first block freed < start */
1490 end = start + len - 1;
1492 * Modify the bitmap to mark this extent freed.
1494 error = xfs_rtmodify_range(mp, tp, start, len, 1);
1495 if (error) {
1496 return error;
1499 * Assume we're freeing out of the middle of an allocated extent.
1500 * We need to find the beginning and end of the extent so we can
1501 * properly update the summary.
1503 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
1504 if (error) {
1505 return error;
1508 * Find the next allocated block (end of allocated extent).
1510 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
1511 &postblock);
1512 if (error)
1513 return error;
1515 * If there are blocks not being freed at the front of the
1516 * old extent, add summary data for them to be allocated.
1518 if (preblock < start) {
1519 error = xfs_rtmodify_summary(mp, tp,
1520 XFS_RTBLOCKLOG(start - preblock),
1521 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
1522 if (error) {
1523 return error;
1527 * If there are blocks not being freed at the end of the
1528 * old extent, add summary data for them to be allocated.
1530 if (postblock > end) {
1531 error = xfs_rtmodify_summary(mp, tp,
1532 XFS_RTBLOCKLOG(postblock - end),
1533 XFS_BITTOBLOCK(mp, end + 1), -1, rbpp, rsb);
1534 if (error) {
1535 return error;
1539 * Increment the summary information corresponding to the entire
1540 * (new) free extent.
1542 error = xfs_rtmodify_summary(mp, tp,
1543 XFS_RTBLOCKLOG(postblock + 1 - preblock),
1544 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
1545 return error;
1549 * Read and return the summary information for a given extent size,
1550 * bitmap block combination.
1551 * Keeps track of a current summary block, so we don't keep reading
1552 * it from the buffer cache.
1554 STATIC int /* error */
1555 xfs_rtget_summary(
1556 xfs_mount_t *mp, /* file system mount structure */
1557 xfs_trans_t *tp, /* transaction pointer */
1558 int log, /* log2 of extent size */
1559 xfs_rtblock_t bbno, /* bitmap block number */
1560 xfs_buf_t **rbpp, /* in/out: summary block buffer */
1561 xfs_fsblock_t *rsb, /* in/out: summary block number */
1562 xfs_suminfo_t *sum) /* out: summary info for this block */
1564 xfs_buf_t *bp; /* buffer for summary block */
1565 int error; /* error value */
1566 xfs_fsblock_t sb; /* summary fsblock */
1567 int so; /* index into the summary file */
1568 xfs_suminfo_t *sp; /* pointer to returned data */
1571 * Compute entry number in the summary file.
1573 so = XFS_SUMOFFS(mp, log, bbno);
1575 * Compute the block number in the summary file.
1577 sb = XFS_SUMOFFSTOBLOCK(mp, so);
1579 * If we have an old buffer, and the block number matches, use that.
1581 if (rbpp && *rbpp && *rsb == sb)
1582 bp = *rbpp;
1584 * Otherwise we have to get the buffer.
1586 else {
1588 * If there was an old one, get rid of it first.
1590 if (rbpp && *rbpp)
1591 xfs_trans_brelse(tp, *rbpp);
1592 error = xfs_rtbuf_get(mp, tp, sb, 1, &bp);
1593 if (error) {
1594 return error;
1597 * Remember this buffer and block for the next call.
1599 if (rbpp) {
1600 *rbpp = bp;
1601 *rsb = sb;
1605 * Point to the summary information & copy it out.
1607 sp = XFS_SUMPTR(mp, bp, so);
1608 *sum = *sp;
1610 * Drop the buffer if we're not asked to remember it.
1612 if (!rbpp)
1613 xfs_trans_brelse(tp, bp);
1614 return 0;
1618 * Set the given range of bitmap bits to the given value.
1619 * Do whatever I/O and logging is required.
1621 STATIC int /* error */
1622 xfs_rtmodify_range(
1623 xfs_mount_t *mp, /* file system mount point */
1624 xfs_trans_t *tp, /* transaction pointer */
1625 xfs_rtblock_t start, /* starting block to modify */
1626 xfs_extlen_t len, /* length of extent to modify */
1627 int val) /* 1 for free, 0 for allocated */
1629 xfs_rtword_t *b; /* current word in buffer */
1630 int bit; /* bit number in the word */
1631 xfs_rtblock_t block; /* bitmap block number */
1632 xfs_buf_t *bp; /* buf for the block */
1633 xfs_rtword_t *bufp; /* starting word in buffer */
1634 int error; /* error value */
1635 xfs_rtword_t *first; /* first used word in the buffer */
1636 int i; /* current bit number rel. to start */
1637 int lastbit; /* last useful bit in word */
1638 xfs_rtword_t mask; /* mask o frelevant bits for value */
1639 int word; /* word number in the buffer */
1642 * Compute starting bitmap block number.
1644 block = XFS_BITTOBLOCK(mp, start);
1646 * Read the bitmap block, and point to its data.
1648 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
1649 if (error) {
1650 return error;
1652 bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1654 * Compute the starting word's address, and starting bit.
1656 word = XFS_BITTOWORD(mp, start);
1657 first = b = &bufp[word];
1658 bit = (int)(start & (XFS_NBWORD - 1));
1660 * 0 (allocated) => all zeroes; 1 (free) => all ones.
1662 val = -val;
1664 * If not starting on a word boundary, deal with the first
1665 * (partial) word.
1667 if (bit) {
1669 * Compute first bit not changed and mask of relevant bits.
1671 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
1672 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
1674 * Set/clear the active bits.
1676 if (val)
1677 *b |= mask;
1678 else
1679 *b &= ~mask;
1680 i = lastbit - bit;
1682 * Go on to the next block if that's where the next word is
1683 * and we need the next word.
1685 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
1687 * Log the changed part of this block.
1688 * Get the next one.
1690 xfs_trans_log_buf(tp, bp,
1691 (uint)((char *)first - (char *)bufp),
1692 (uint)((char *)b - (char *)bufp));
1693 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
1694 if (error) {
1695 return error;
1697 first = b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1698 word = 0;
1699 } else {
1701 * Go on to the next word in the buffer
1703 b++;
1705 } else {
1707 * Starting on a word boundary, no partial word.
1709 i = 0;
1712 * Loop over whole words in buffers. When we use up one buffer
1713 * we move on to the next one.
1715 while (len - i >= XFS_NBWORD) {
1717 * Set the word value correctly.
1719 *b = val;
1720 i += XFS_NBWORD;
1722 * Go on to the next block if that's where the next word is
1723 * and we need the next word.
1725 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
1727 * Log the changed part of this block.
1728 * Get the next one.
1730 xfs_trans_log_buf(tp, bp,
1731 (uint)((char *)first - (char *)bufp),
1732 (uint)((char *)b - (char *)bufp));
1733 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
1734 if (error) {
1735 return error;
1737 first = b = bufp = (xfs_rtword_t *)XFS_BUF_PTR(bp);
1738 word = 0;
1739 } else {
1741 * Go on to the next word in the buffer
1743 b++;
1747 * If not ending on a word boundary, deal with the last
1748 * (partial) word.
1750 if ((lastbit = len - i)) {
1752 * Compute a mask of relevant bits.
1754 bit = 0;
1755 mask = ((xfs_rtword_t)1 << lastbit) - 1;
1757 * Set/clear the active bits.
1759 if (val)
1760 *b |= mask;
1761 else
1762 *b &= ~mask;
1763 b++;
1766 * Log any remaining changed bytes.
1768 if (b > first)
1769 xfs_trans_log_buf(tp, bp, (uint)((char *)first - (char *)bufp),
1770 (uint)((char *)b - (char *)bufp - 1));
1771 return 0;
1775 * Read and modify the summary information for a given extent size,
1776 * bitmap block combination.
1777 * Keeps track of a current summary block, so we don't keep reading
1778 * it from the buffer cache.
1780 STATIC int /* error */
1781 xfs_rtmodify_summary(
1782 xfs_mount_t *mp, /* file system mount point */
1783 xfs_trans_t *tp, /* transaction pointer */
1784 int log, /* log2 of extent size */
1785 xfs_rtblock_t bbno, /* bitmap block number */
1786 int delta, /* change to make to summary info */
1787 xfs_buf_t **rbpp, /* in/out: summary block buffer */
1788 xfs_fsblock_t *rsb) /* in/out: summary block number */
1790 xfs_buf_t *bp; /* buffer for the summary block */
1791 int error; /* error value */
1792 xfs_fsblock_t sb; /* summary fsblock */
1793 int so; /* index into the summary file */
1794 xfs_suminfo_t *sp; /* pointer to returned data */
1797 * Compute entry number in the summary file.
1799 so = XFS_SUMOFFS(mp, log, bbno);
1801 * Compute the block number in the summary file.
1803 sb = XFS_SUMOFFSTOBLOCK(mp, so);
1805 * If we have an old buffer, and the block number matches, use that.
1807 if (rbpp && *rbpp && *rsb == sb)
1808 bp = *rbpp;
1810 * Otherwise we have to get the buffer.
1812 else {
1814 * If there was an old one, get rid of it first.
1816 if (rbpp && *rbpp)
1817 xfs_trans_brelse(tp, *rbpp);
1818 error = xfs_rtbuf_get(mp, tp, sb, 1, &bp);
1819 if (error) {
1820 return error;
1823 * Remember this buffer and block for the next call.
1825 if (rbpp) {
1826 *rbpp = bp;
1827 *rsb = sb;
1831 * Point to the summary information, modify and log it.
1833 sp = XFS_SUMPTR(mp, bp, so);
1834 *sp += delta;
1835 xfs_trans_log_buf(tp, bp, (uint)((char *)sp - (char *)XFS_BUF_PTR(bp)),
1836 (uint)((char *)sp - (char *)XFS_BUF_PTR(bp) + sizeof(*sp) - 1));
1837 return 0;
1841 * Visible (exported) functions.
1845 * Grow the realtime area of the filesystem.
1848 xfs_growfs_rt(
1849 xfs_mount_t *mp, /* mount point for filesystem */
1850 xfs_growfs_rt_t *in) /* growfs rt input struct */
1852 xfs_rtblock_t bmbno; /* bitmap block number */
1853 xfs_buf_t *bp; /* temporary buffer */
1854 int error; /* error return value */
1855 xfs_mount_t *nmp; /* new (fake) mount structure */
1856 xfs_drfsbno_t nrblocks; /* new number of realtime blocks */
1857 xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
1858 xfs_drtbno_t nrextents; /* new number of realtime extents */
1859 uint8_t nrextslog; /* new log2 of sb_rextents */
1860 xfs_extlen_t nrsumblocks; /* new number of summary blocks */
1861 uint nrsumlevels; /* new rt summary levels */
1862 uint nrsumsize; /* new size of rt summary, bytes */
1863 xfs_sb_t *nsbp; /* new superblock */
1864 xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
1865 xfs_extlen_t rsumblocks; /* current number of rt summary blks */
1866 xfs_sb_t *sbp; /* old superblock */
1867 xfs_fsblock_t sumbno; /* summary block number */
1869 sbp = &mp->m_sb;
1871 * Initial error checking.
1873 if (!capable(CAP_SYS_ADMIN))
1874 return XFS_ERROR(EPERM);
1875 if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
1876 (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
1877 (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
1878 return XFS_ERROR(EINVAL);
1879 if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
1880 return error;
1882 * Read in the last block of the device, make sure it exists.
1884 bp = xfs_buf_read_uncached(mp, mp->m_rtdev_targp,
1885 XFS_FSB_TO_BB(mp, nrblocks - 1),
1886 XFS_FSB_TO_B(mp, 1), 0);
1887 if (!bp)
1888 return EIO;
1889 xfs_buf_relse(bp);
1892 * Calculate new parameters. These are the final values to be reached.
1894 nrextents = nrblocks;
1895 do_div(nrextents, in->extsize);
1896 nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
1897 nrextslog = xfs_highbit32(nrextents);
1898 nrsumlevels = nrextslog + 1;
1899 nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
1900 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
1901 nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1903 * New summary size can't be more than half the size of
1904 * the log. This prevents us from getting a log overflow,
1905 * since we'll log basically the whole summary file at once.
1907 if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
1908 return XFS_ERROR(EINVAL);
1910 * Get the old block counts for bitmap and summary inodes.
1911 * These can't change since other growfs callers are locked out.
1913 rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
1914 rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
1916 * Allocate space to the bitmap and summary files, as necessary.
1918 error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
1919 if (error)
1920 return error;
1921 error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
1922 if (error)
1923 return error;
1925 * Allocate a new (fake) mount/sb.
1927 nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
1929 * Loop over the bitmap blocks.
1930 * We will do everything one bitmap block at a time.
1931 * Skip the current block if it is exactly full.
1932 * This also deals with the case where there were no rtextents before.
1934 for (bmbno = sbp->sb_rbmblocks -
1935 ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
1936 bmbno < nrbmblocks;
1937 bmbno++) {
1938 xfs_trans_t *tp;
1939 int cancelflags = 0;
1941 *nmp = *mp;
1942 nsbp = &nmp->m_sb;
1944 * Calculate new sb and mount fields for this round.
1946 nsbp->sb_rextsize = in->extsize;
1947 nsbp->sb_rbmblocks = bmbno + 1;
1948 nsbp->sb_rblocks =
1949 XFS_RTMIN(nrblocks,
1950 nsbp->sb_rbmblocks * NBBY *
1951 nsbp->sb_blocksize * nsbp->sb_rextsize);
1952 nsbp->sb_rextents = nsbp->sb_rblocks;
1953 do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
1954 ASSERT(nsbp->sb_rextents != 0);
1955 nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
1956 nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
1957 nrsumsize =
1958 (uint)sizeof(xfs_suminfo_t) * nrsumlevels *
1959 nsbp->sb_rbmblocks;
1960 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
1961 nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1963 * Start a transaction, get the log reservation.
1965 tp = xfs_trans_alloc(mp, XFS_TRANS_GROWFSRT_FREE);
1966 if ((error = xfs_trans_reserve(tp, 0,
1967 XFS_GROWRTFREE_LOG_RES(nmp), 0, 0, 0)))
1968 goto error_cancel;
1970 * Lock out other callers by grabbing the bitmap inode lock.
1972 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1973 xfs_trans_ijoin_ref(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1975 * Update the bitmap inode's size.
1977 mp->m_rbmip->i_d.di_size =
1978 nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1979 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1980 cancelflags |= XFS_TRANS_ABORT;
1982 * Get the summary inode into the transaction.
1984 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1985 xfs_trans_ijoin_ref(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1987 * Update the summary inode's size.
1989 mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1990 xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1992 * Copy summary data from old to new sizes.
1993 * Do this when the real size (not block-aligned) changes.
1995 if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1996 mp->m_rsumlevels != nmp->m_rsumlevels) {
1997 error = xfs_rtcopy_summary(mp, nmp, tp);
1998 if (error)
1999 goto error_cancel;
2002 * Update superblock fields.
2004 if (nsbp->sb_rextsize != sbp->sb_rextsize)
2005 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
2006 nsbp->sb_rextsize - sbp->sb_rextsize);
2007 if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
2008 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
2009 nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
2010 if (nsbp->sb_rblocks != sbp->sb_rblocks)
2011 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
2012 nsbp->sb_rblocks - sbp->sb_rblocks);
2013 if (nsbp->sb_rextents != sbp->sb_rextents)
2014 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
2015 nsbp->sb_rextents - sbp->sb_rextents);
2016 if (nsbp->sb_rextslog != sbp->sb_rextslog)
2017 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
2018 nsbp->sb_rextslog - sbp->sb_rextslog);
2020 * Free new extent.
2022 bp = NULL;
2023 error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
2024 nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
2025 if (error) {
2026 error_cancel:
2027 xfs_trans_cancel(tp, cancelflags);
2028 break;
2031 * Mark more blocks free in the superblock.
2033 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
2034 nsbp->sb_rextents - sbp->sb_rextents);
2036 * Update mp values into the real mp structure.
2038 mp->m_rsumlevels = nrsumlevels;
2039 mp->m_rsumsize = nrsumsize;
2041 error = xfs_trans_commit(tp, 0);
2042 if (error)
2043 break;
2047 * Free the fake mp structure.
2049 kmem_free(nmp);
2051 return error;
2055 * Allocate an extent in the realtime subvolume, with the usual allocation
2056 * parameters. The length units are all in realtime extents, as is the
2057 * result block number.
2059 int /* error */
2060 xfs_rtallocate_extent(
2061 xfs_trans_t *tp, /* transaction pointer */
2062 xfs_rtblock_t bno, /* starting block number to allocate */
2063 xfs_extlen_t minlen, /* minimum length to allocate */
2064 xfs_extlen_t maxlen, /* maximum length to allocate */
2065 xfs_extlen_t *len, /* out: actual length allocated */
2066 xfs_alloctype_t type, /* allocation type XFS_ALLOCTYPE... */
2067 int wasdel, /* was a delayed allocation extent */
2068 xfs_extlen_t prod, /* extent product factor */
2069 xfs_rtblock_t *rtblock) /* out: start block allocated */
2071 xfs_mount_t *mp = tp->t_mountp;
2072 int error; /* error value */
2073 xfs_rtblock_t r; /* result allocated block */
2074 xfs_fsblock_t sb; /* summary file block number */
2075 xfs_buf_t *sumbp; /* summary file block buffer */
2077 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
2078 ASSERT(minlen > 0 && minlen <= maxlen);
2081 * If prod is set then figure out what to do to minlen and maxlen.
2083 if (prod > 1) {
2084 xfs_extlen_t i;
2086 if ((i = maxlen % prod))
2087 maxlen -= i;
2088 if ((i = minlen % prod))
2089 minlen += prod - i;
2090 if (maxlen < minlen) {
2091 *rtblock = NULLRTBLOCK;
2092 return 0;
2096 sumbp = NULL;
2098 * Allocate by size, or near another block, or exactly at some block.
2100 switch (type) {
2101 case XFS_ALLOCTYPE_ANY_AG:
2102 error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
2103 &sumbp, &sb, prod, &r);
2104 break;
2105 case XFS_ALLOCTYPE_NEAR_BNO:
2106 error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
2107 len, &sumbp, &sb, prod, &r);
2108 break;
2109 case XFS_ALLOCTYPE_THIS_BNO:
2110 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen,
2111 len, &sumbp, &sb, prod, &r);
2112 break;
2113 default:
2114 error = EIO;
2115 ASSERT(0);
2117 if (error)
2118 return error;
2121 * If it worked, update the superblock.
2123 if (r != NULLRTBLOCK) {
2124 long slen = (long)*len;
2126 ASSERT(*len >= minlen && *len <= maxlen);
2127 if (wasdel)
2128 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
2129 else
2130 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
2132 *rtblock = r;
2133 return 0;
2137 * Free an extent in the realtime subvolume. Length is expressed in
2138 * realtime extents, as is the block number.
2140 int /* error */
2141 xfs_rtfree_extent(
2142 xfs_trans_t *tp, /* transaction pointer */
2143 xfs_rtblock_t bno, /* starting block number to free */
2144 xfs_extlen_t len) /* length of extent freed */
2146 int error; /* error value */
2147 xfs_mount_t *mp; /* file system mount structure */
2148 xfs_fsblock_t sb; /* summary file block number */
2149 xfs_buf_t *sumbp; /* summary file block buffer */
2151 mp = tp->t_mountp;
2153 * Synchronize by locking the bitmap inode.
2155 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
2156 xfs_trans_ijoin_ref(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
2158 #if defined(__KERNEL__) && defined(DEBUG)
2160 * Check to see that this whole range is currently allocated.
2163 int stat; /* result from checking range */
2165 error = xfs_rtcheck_alloc_range(mp, tp, bno, len, &stat);
2166 if (error) {
2167 return error;
2169 ASSERT(stat);
2171 #endif
2172 sumbp = NULL;
2174 * Free the range of realtime blocks.
2176 error = xfs_rtfree_range(mp, tp, bno, len, &sumbp, &sb);
2177 if (error) {
2178 return error;
2181 * Mark more blocks free in the superblock.
2183 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
2185 * If we've now freed all the blocks, reset the file sequence
2186 * number to 0.
2188 if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
2189 mp->m_sb.sb_rextents) {
2190 if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM))
2191 mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
2192 *(__uint64_t *)&mp->m_rbmip->i_d.di_atime = 0;
2193 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
2195 return 0;
2199 * Initialize realtime fields in the mount structure.
2201 int /* error */
2202 xfs_rtmount_init(
2203 xfs_mount_t *mp) /* file system mount structure */
2205 xfs_buf_t *bp; /* buffer for last block of subvolume */
2206 xfs_daddr_t d; /* address of last block of subvolume */
2207 xfs_sb_t *sbp; /* filesystem superblock copy in mount */
2209 sbp = &mp->m_sb;
2210 if (sbp->sb_rblocks == 0)
2211 return 0;
2212 if (mp->m_rtdev_targp == NULL) {
2213 xfs_warn(mp,
2214 "Filesystem has a realtime volume, use rtdev=device option");
2215 return XFS_ERROR(ENODEV);
2217 mp->m_rsumlevels = sbp->sb_rextslog + 1;
2218 mp->m_rsumsize =
2219 (uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
2220 sbp->sb_rbmblocks;
2221 mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
2222 mp->m_rbmip = mp->m_rsumip = NULL;
2224 * Check that the realtime section is an ok size.
2226 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
2227 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
2228 xfs_warn(mp, "realtime mount -- %llu != %llu",
2229 (unsigned long long) XFS_BB_TO_FSB(mp, d),
2230 (unsigned long long) mp->m_sb.sb_rblocks);
2231 return XFS_ERROR(EFBIG);
2233 bp = xfs_buf_read_uncached(mp, mp->m_rtdev_targp,
2234 d - XFS_FSB_TO_BB(mp, 1),
2235 XFS_FSB_TO_B(mp, 1), 0);
2236 if (!bp) {
2237 xfs_warn(mp, "realtime device size check failed");
2238 return EIO;
2240 xfs_buf_relse(bp);
2241 return 0;
2245 * Get the bitmap and summary inodes into the mount structure
2246 * at mount time.
2248 int /* error */
2249 xfs_rtmount_inodes(
2250 xfs_mount_t *mp) /* file system mount structure */
2252 int error; /* error return value */
2253 xfs_sb_t *sbp;
2255 sbp = &mp->m_sb;
2256 if (sbp->sb_rbmino == NULLFSINO)
2257 return 0;
2258 error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
2259 if (error)
2260 return error;
2261 ASSERT(mp->m_rbmip != NULL);
2262 ASSERT(sbp->sb_rsumino != NULLFSINO);
2263 error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
2264 if (error) {
2265 IRELE(mp->m_rbmip);
2266 return error;
2268 ASSERT(mp->m_rsumip != NULL);
2269 return 0;
2272 void
2273 xfs_rtunmount_inodes(
2274 struct xfs_mount *mp)
2276 if (mp->m_rbmip)
2277 IRELE(mp->m_rbmip);
2278 if (mp->m_rsumip)
2279 IRELE(mp->m_rsumip);
2283 * Pick an extent for allocation at the start of a new realtime file.
2284 * Use the sequence number stored in the atime field of the bitmap inode.
2285 * Translate this to a fraction of the rtextents, and return the product
2286 * of rtextents and the fraction.
2287 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
2289 int /* error */
2290 xfs_rtpick_extent(
2291 xfs_mount_t *mp, /* file system mount point */
2292 xfs_trans_t *tp, /* transaction pointer */
2293 xfs_extlen_t len, /* allocation length (rtextents) */
2294 xfs_rtblock_t *pick) /* result rt extent */
2296 xfs_rtblock_t b; /* result block */
2297 int log2; /* log of sequence number */
2298 __uint64_t resid; /* residual after log removed */
2299 __uint64_t seq; /* sequence number of file creation */
2300 __uint64_t *seqp; /* pointer to seqno in inode */
2302 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
2304 seqp = (__uint64_t *)&mp->m_rbmip->i_d.di_atime;
2305 if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
2306 mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
2307 *seqp = 0;
2309 seq = *seqp;
2310 if ((log2 = xfs_highbit64(seq)) == -1)
2311 b = 0;
2312 else {
2313 resid = seq - (1ULL << log2);
2314 b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
2315 (log2 + 1);
2316 if (b >= mp->m_sb.sb_rextents)
2317 b = do_mod(b, mp->m_sb.sb_rextents);
2318 if (b + len > mp->m_sb.sb_rextents)
2319 b = mp->m_sb.sb_rextents - len;
2321 *seqp = seq + 1;
2322 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
2323 *pick = b;
2324 return 0;