mm: discard memblock data later
[linux/fpc-iii.git] / fs / xfs / xfs_rtalloc.c
blob802bcc326d9fbe37fab8b412ce69b37390d94ba0
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_shared.h"
21 #include "xfs_format.h"
22 #include "xfs_log_format.h"
23 #include "xfs_trans_resv.h"
24 #include "xfs_bit.h"
25 #include "xfs_mount.h"
26 #include "xfs_defer.h"
27 #include "xfs_inode.h"
28 #include "xfs_bmap.h"
29 #include "xfs_bmap_util.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_alloc.h"
32 #include "xfs_error.h"
33 #include "xfs_trans.h"
34 #include "xfs_trans_space.h"
35 #include "xfs_trace.h"
36 #include "xfs_buf.h"
37 #include "xfs_icache.h"
38 #include "xfs_rtalloc.h"
42 * Read and return the summary information for a given extent size,
43 * bitmap block combination.
44 * Keeps track of a current summary block, so we don't keep reading
45 * it from the buffer cache.
47 static int
48 xfs_rtget_summary(
49 xfs_mount_t *mp, /* file system mount structure */
50 xfs_trans_t *tp, /* transaction pointer */
51 int log, /* log2 of extent size */
52 xfs_rtblock_t bbno, /* bitmap block number */
53 xfs_buf_t **rbpp, /* in/out: summary block buffer */
54 xfs_fsblock_t *rsb, /* in/out: summary block number */
55 xfs_suminfo_t *sum) /* out: summary info for this block */
57 return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
61 * Return whether there are any free extents in the size range given
62 * by low and high, for the bitmap block bbno.
64 STATIC int /* error */
65 xfs_rtany_summary(
66 xfs_mount_t *mp, /* file system mount structure */
67 xfs_trans_t *tp, /* transaction pointer */
68 int low, /* low log2 extent size */
69 int high, /* high log2 extent size */
70 xfs_rtblock_t bbno, /* bitmap block number */
71 xfs_buf_t **rbpp, /* in/out: summary block buffer */
72 xfs_fsblock_t *rsb, /* in/out: summary block number */
73 int *stat) /* out: any good extents here? */
75 int error; /* error value */
76 int log; /* loop counter, log2 of ext. size */
77 xfs_suminfo_t sum; /* summary data */
80 * Loop over logs of extent sizes. Order is irrelevant.
82 for (log = low; log <= high; log++) {
84 * Get one summary datum.
86 error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
87 if (error) {
88 return error;
91 * If there are any, return success.
93 if (sum) {
94 *stat = 1;
95 return 0;
99 * Found nothing, return failure.
101 *stat = 0;
102 return 0;
107 * Copy and transform the summary file, given the old and new
108 * parameters in the mount structures.
110 STATIC int /* error */
111 xfs_rtcopy_summary(
112 xfs_mount_t *omp, /* old file system mount point */
113 xfs_mount_t *nmp, /* new file system mount point */
114 xfs_trans_t *tp) /* transaction pointer */
116 xfs_rtblock_t bbno; /* bitmap block number */
117 xfs_buf_t *bp; /* summary buffer */
118 int error; /* error return value */
119 int log; /* summary level number (log length) */
120 xfs_suminfo_t sum; /* summary data */
121 xfs_fsblock_t sumbno; /* summary block number */
123 bp = NULL;
124 for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
125 for (bbno = omp->m_sb.sb_rbmblocks - 1;
126 (xfs_srtblock_t)bbno >= 0;
127 bbno--) {
128 error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
129 &sumbno, &sum);
130 if (error)
131 return error;
132 if (sum == 0)
133 continue;
134 error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
135 &bp, &sumbno);
136 if (error)
137 return error;
138 error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
139 &bp, &sumbno);
140 if (error)
141 return error;
142 ASSERT(sum > 0);
145 return 0;
148 * Mark an extent specified by start and len allocated.
149 * Updates all the summary information as well as the bitmap.
151 STATIC int /* error */
152 xfs_rtallocate_range(
153 xfs_mount_t *mp, /* file system mount point */
154 xfs_trans_t *tp, /* transaction pointer */
155 xfs_rtblock_t start, /* start block to allocate */
156 xfs_extlen_t len, /* length to allocate */
157 xfs_buf_t **rbpp, /* in/out: summary block buffer */
158 xfs_fsblock_t *rsb) /* in/out: summary block number */
160 xfs_rtblock_t end; /* end of the allocated extent */
161 int error; /* error value */
162 xfs_rtblock_t postblock = 0; /* first block allocated > end */
163 xfs_rtblock_t preblock = 0; /* first block allocated < start */
165 end = start + len - 1;
167 * Assume we're allocating out of the middle of a free extent.
168 * We need to find the beginning and end of the extent so we can
169 * properly update the summary.
171 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
172 if (error) {
173 return error;
176 * Find the next allocated block (end of free extent).
178 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
179 &postblock);
180 if (error) {
181 return error;
184 * Decrement the summary information corresponding to the entire
185 * (old) free extent.
187 error = xfs_rtmodify_summary(mp, tp,
188 XFS_RTBLOCKLOG(postblock + 1 - preblock),
189 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
190 if (error) {
191 return error;
194 * If there are blocks not being allocated at the front of the
195 * old extent, add summary data for them to be free.
197 if (preblock < start) {
198 error = xfs_rtmodify_summary(mp, tp,
199 XFS_RTBLOCKLOG(start - preblock),
200 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
201 if (error) {
202 return error;
206 * If there are blocks not being allocated at the end of the
207 * old extent, add summary data for them to be free.
209 if (postblock > end) {
210 error = xfs_rtmodify_summary(mp, tp,
211 XFS_RTBLOCKLOG(postblock - end),
212 XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
213 if (error) {
214 return error;
218 * Modify the bitmap to mark this extent allocated.
220 error = xfs_rtmodify_range(mp, tp, start, len, 0);
221 return error;
225 * Attempt to allocate an extent minlen<=len<=maxlen starting from
226 * bitmap block bbno. If we don't get maxlen then use prod to trim
227 * the length, if given. Returns error; returns starting block in *rtblock.
228 * The lengths are all in rtextents.
230 STATIC int /* error */
231 xfs_rtallocate_extent_block(
232 xfs_mount_t *mp, /* file system mount point */
233 xfs_trans_t *tp, /* transaction pointer */
234 xfs_rtblock_t bbno, /* bitmap block number */
235 xfs_extlen_t minlen, /* minimum length to allocate */
236 xfs_extlen_t maxlen, /* maximum length to allocate */
237 xfs_extlen_t *len, /* out: actual length allocated */
238 xfs_rtblock_t *nextp, /* out: next block to try */
239 xfs_buf_t **rbpp, /* in/out: summary block buffer */
240 xfs_fsblock_t *rsb, /* in/out: summary block number */
241 xfs_extlen_t prod, /* extent product factor */
242 xfs_rtblock_t *rtblock) /* out: start block allocated */
244 xfs_rtblock_t besti; /* best rtblock found so far */
245 xfs_rtblock_t bestlen; /* best length found so far */
246 xfs_rtblock_t end; /* last rtblock in chunk */
247 int error; /* error value */
248 xfs_rtblock_t i; /* current rtblock trying */
249 xfs_rtblock_t next; /* next rtblock to try */
250 int stat; /* status from internal calls */
253 * Loop over all the extents starting in this bitmap block,
254 * looking for one that's long enough.
256 for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
257 end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
258 i <= end;
259 i++) {
261 * See if there's a free extent of maxlen starting at i.
262 * If it's not so then next will contain the first non-free.
264 error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
265 if (error) {
266 return error;
268 if (stat) {
270 * i for maxlen is all free, allocate and return that.
272 error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
273 rsb);
274 if (error) {
275 return error;
277 *len = maxlen;
278 *rtblock = i;
279 return 0;
282 * In the case where we have a variable-sized allocation
283 * request, figure out how big this free piece is,
284 * and if it's big enough for the minimum, and the best
285 * so far, remember it.
287 if (minlen < maxlen) {
288 xfs_rtblock_t thislen; /* this extent size */
290 thislen = next - i;
291 if (thislen >= minlen && thislen > bestlen) {
292 besti = i;
293 bestlen = thislen;
297 * If not done yet, find the start of the next free space.
299 if (next < end) {
300 error = xfs_rtfind_forw(mp, tp, next, end, &i);
301 if (error) {
302 return error;
304 } else
305 break;
308 * Searched the whole thing & didn't find a maxlen free extent.
310 if (minlen < maxlen && besti != -1) {
311 xfs_extlen_t p; /* amount to trim length by */
314 * If size should be a multiple of prod, make that so.
316 if (prod > 1 && (p = do_mod(bestlen, prod)))
317 bestlen -= p;
319 * Allocate besti for bestlen & return that.
321 error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
322 if (error) {
323 return error;
325 *len = bestlen;
326 *rtblock = besti;
327 return 0;
330 * Allocation failed. Set *nextp to the next block to try.
332 *nextp = next;
333 *rtblock = NULLRTBLOCK;
334 return 0;
338 * Allocate an extent of length minlen<=len<=maxlen, starting at block
339 * bno. If we don't get maxlen then use prod to trim the length, if given.
340 * Returns error; returns starting block in *rtblock.
341 * The lengths are all in rtextents.
343 STATIC int /* error */
344 xfs_rtallocate_extent_exact(
345 xfs_mount_t *mp, /* file system mount point */
346 xfs_trans_t *tp, /* transaction pointer */
347 xfs_rtblock_t bno, /* starting block number to allocate */
348 xfs_extlen_t minlen, /* minimum length to allocate */
349 xfs_extlen_t maxlen, /* maximum length to allocate */
350 xfs_extlen_t *len, /* out: actual length allocated */
351 xfs_buf_t **rbpp, /* in/out: summary block buffer */
352 xfs_fsblock_t *rsb, /* in/out: summary block number */
353 xfs_extlen_t prod, /* extent product factor */
354 xfs_rtblock_t *rtblock) /* out: start block allocated */
356 int error; /* error value */
357 xfs_extlen_t i; /* extent length trimmed due to prod */
358 int isfree; /* extent is free */
359 xfs_rtblock_t next; /* next block to try (dummy) */
361 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
363 * Check if the range in question (for maxlen) is free.
365 error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
366 if (error) {
367 return error;
369 if (isfree) {
371 * If it is, allocate it and return success.
373 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
374 if (error) {
375 return error;
377 *len = maxlen;
378 *rtblock = bno;
379 return 0;
382 * If not, allocate what there is, if it's at least minlen.
384 maxlen = next - bno;
385 if (maxlen < minlen) {
387 * Failed, return failure status.
389 *rtblock = NULLRTBLOCK;
390 return 0;
393 * Trim off tail of extent, if prod is specified.
395 if (prod > 1 && (i = maxlen % prod)) {
396 maxlen -= i;
397 if (maxlen < minlen) {
399 * Now we can't do it, return failure status.
401 *rtblock = NULLRTBLOCK;
402 return 0;
406 * Allocate what we can and return it.
408 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
409 if (error) {
410 return error;
412 *len = maxlen;
413 *rtblock = bno;
414 return 0;
418 * Allocate an extent of length minlen<=len<=maxlen, starting as near
419 * to bno as possible. If we don't get maxlen then use prod to trim
420 * the length, if given. The lengths are all in rtextents.
422 STATIC int /* error */
423 xfs_rtallocate_extent_near(
424 xfs_mount_t *mp, /* file system mount point */
425 xfs_trans_t *tp, /* transaction pointer */
426 xfs_rtblock_t bno, /* starting block number to allocate */
427 xfs_extlen_t minlen, /* minimum length to allocate */
428 xfs_extlen_t maxlen, /* maximum length to allocate */
429 xfs_extlen_t *len, /* out: actual length allocated */
430 xfs_buf_t **rbpp, /* in/out: summary block buffer */
431 xfs_fsblock_t *rsb, /* in/out: summary block number */
432 xfs_extlen_t prod, /* extent product factor */
433 xfs_rtblock_t *rtblock) /* out: start block allocated */
435 int any; /* any useful extents from summary */
436 xfs_rtblock_t bbno; /* bitmap block number */
437 int error; /* error value */
438 int i; /* bitmap block offset (loop control) */
439 int j; /* secondary loop control */
440 int log2len; /* log2 of minlen */
441 xfs_rtblock_t n; /* next block to try */
442 xfs_rtblock_t r; /* result block */
444 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
446 * If the block number given is off the end, silently set it to
447 * the last block.
449 if (bno >= mp->m_sb.sb_rextents)
450 bno = mp->m_sb.sb_rextents - 1;
452 * Try the exact allocation first.
454 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
455 rbpp, rsb, prod, &r);
456 if (error) {
457 return error;
460 * If the exact allocation worked, return that.
462 if (r != NULLRTBLOCK) {
463 *rtblock = r;
464 return 0;
466 bbno = XFS_BITTOBLOCK(mp, bno);
467 i = 0;
468 ASSERT(minlen != 0);
469 log2len = xfs_highbit32(minlen);
471 * Loop over all bitmap blocks (bbno + i is current block).
473 for (;;) {
475 * Get summary information of extents of all useful levels
476 * starting in this bitmap block.
478 error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
479 bbno + i, rbpp, rsb, &any);
480 if (error) {
481 return error;
484 * If there are any useful extents starting here, try
485 * allocating one.
487 if (any) {
489 * On the positive side of the starting location.
491 if (i >= 0) {
493 * Try to allocate an extent starting in
494 * this block.
496 error = xfs_rtallocate_extent_block(mp, tp,
497 bbno + i, minlen, maxlen, len, &n, rbpp,
498 rsb, prod, &r);
499 if (error) {
500 return error;
503 * If it worked, return it.
505 if (r != NULLRTBLOCK) {
506 *rtblock = r;
507 return 0;
511 * On the negative side of the starting location.
513 else { /* i < 0 */
515 * Loop backwards through the bitmap blocks from
516 * the starting point-1 up to where we are now.
517 * There should be an extent which ends in this
518 * bitmap block and is long enough.
520 for (j = -1; j > i; j--) {
522 * Grab the summary information for
523 * this bitmap block.
525 error = xfs_rtany_summary(mp, tp,
526 log2len, mp->m_rsumlevels - 1,
527 bbno + j, rbpp, rsb, &any);
528 if (error) {
529 return error;
532 * If there's no extent given in the
533 * summary that means the extent we
534 * found must carry over from an
535 * earlier block. If there is an
536 * extent given, we've already tried
537 * that allocation, don't do it again.
539 if (any)
540 continue;
541 error = xfs_rtallocate_extent_block(mp,
542 tp, bbno + j, minlen, maxlen,
543 len, &n, rbpp, rsb, prod, &r);
544 if (error) {
545 return error;
548 * If it works, return the extent.
550 if (r != NULLRTBLOCK) {
551 *rtblock = r;
552 return 0;
556 * There weren't intervening bitmap blocks
557 * with a long enough extent, or the
558 * allocation didn't work for some reason
559 * (i.e. it's a little * too short).
560 * Try to allocate from the summary block
561 * that we found.
563 error = xfs_rtallocate_extent_block(mp, tp,
564 bbno + i, minlen, maxlen, len, &n, rbpp,
565 rsb, prod, &r);
566 if (error) {
567 return error;
570 * If it works, return the extent.
572 if (r != NULLRTBLOCK) {
573 *rtblock = r;
574 return 0;
579 * Loop control. If we were on the positive side, and there's
580 * still more blocks on the negative side, go there.
582 if (i > 0 && (int)bbno - i >= 0)
583 i = -i;
585 * If positive, and no more negative, but there are more
586 * positive, go there.
588 else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
589 i++;
591 * If negative or 0 (just started), and there are positive
592 * blocks to go, go there. The 0 case moves to block 1.
594 else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
595 i = 1 - i;
597 * If negative or 0 and there are more negative blocks,
598 * go there.
600 else if (i <= 0 && (int)bbno + i > 0)
601 i--;
603 * Must be done. Return failure.
605 else
606 break;
608 *rtblock = NULLRTBLOCK;
609 return 0;
613 * Allocate an extent of length minlen<=len<=maxlen, with no position
614 * specified. If we don't get maxlen then use prod to trim
615 * the length, if given. The lengths are all in rtextents.
617 STATIC int /* error */
618 xfs_rtallocate_extent_size(
619 xfs_mount_t *mp, /* file system mount point */
620 xfs_trans_t *tp, /* transaction pointer */
621 xfs_extlen_t minlen, /* minimum length to allocate */
622 xfs_extlen_t maxlen, /* maximum length to allocate */
623 xfs_extlen_t *len, /* out: actual length allocated */
624 xfs_buf_t **rbpp, /* in/out: summary block buffer */
625 xfs_fsblock_t *rsb, /* in/out: summary block number */
626 xfs_extlen_t prod, /* extent product factor */
627 xfs_rtblock_t *rtblock) /* out: start block allocated */
629 int error; /* error value */
630 int i; /* bitmap block number */
631 int l; /* level number (loop control) */
632 xfs_rtblock_t n; /* next block to be tried */
633 xfs_rtblock_t r; /* result block number */
634 xfs_suminfo_t sum; /* summary information for extents */
636 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
637 ASSERT(maxlen != 0);
640 * Loop over all the levels starting with maxlen.
641 * At each level, look at all the bitmap blocks, to see if there
642 * are extents starting there that are long enough (>= maxlen).
643 * Note, only on the initial level can the allocation fail if
644 * the summary says there's an extent.
646 for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
648 * Loop over all the bitmap blocks.
650 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
652 * Get the summary for this level/block.
654 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
655 &sum);
656 if (error) {
657 return error;
660 * Nothing there, on to the next block.
662 if (!sum)
663 continue;
665 * Try allocating the extent.
667 error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
668 maxlen, len, &n, rbpp, rsb, prod, &r);
669 if (error) {
670 return error;
673 * If it worked, return that.
675 if (r != NULLRTBLOCK) {
676 *rtblock = r;
677 return 0;
680 * If the "next block to try" returned from the
681 * allocator is beyond the next bitmap block,
682 * skip to that bitmap block.
684 if (XFS_BITTOBLOCK(mp, n) > i + 1)
685 i = XFS_BITTOBLOCK(mp, n) - 1;
689 * Didn't find any maxlen blocks. Try smaller ones, unless
690 * we're asking for a fixed size extent.
692 if (minlen > --maxlen) {
693 *rtblock = NULLRTBLOCK;
694 return 0;
696 ASSERT(minlen != 0);
697 ASSERT(maxlen != 0);
700 * Loop over sizes, from maxlen down to minlen.
701 * This time, when we do the allocations, allow smaller ones
702 * to succeed.
704 for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
706 * Loop over all the bitmap blocks, try an allocation
707 * starting in that block.
709 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
711 * Get the summary information for this level/block.
713 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
714 &sum);
715 if (error) {
716 return error;
719 * If nothing there, go on to next.
721 if (!sum)
722 continue;
724 * Try the allocation. Make sure the specified
725 * minlen/maxlen are in the possible range for
726 * this summary level.
728 error = xfs_rtallocate_extent_block(mp, tp, i,
729 XFS_RTMAX(minlen, 1 << l),
730 XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
731 len, &n, rbpp, rsb, prod, &r);
732 if (error) {
733 return error;
736 * If it worked, return that extent.
738 if (r != NULLRTBLOCK) {
739 *rtblock = r;
740 return 0;
743 * If the "next block to try" returned from the
744 * allocator is beyond the next bitmap block,
745 * skip to that bitmap block.
747 if (XFS_BITTOBLOCK(mp, n) > i + 1)
748 i = XFS_BITTOBLOCK(mp, n) - 1;
752 * Got nothing, return failure.
754 *rtblock = NULLRTBLOCK;
755 return 0;
759 * Allocate space to the bitmap or summary file, and zero it, for growfs.
761 STATIC int
762 xfs_growfs_rt_alloc(
763 struct xfs_mount *mp, /* file system mount point */
764 xfs_extlen_t oblocks, /* old count of blocks */
765 xfs_extlen_t nblocks, /* new count of blocks */
766 struct xfs_inode *ip) /* inode (bitmap/summary) */
768 xfs_fileoff_t bno; /* block number in file */
769 struct xfs_buf *bp; /* temporary buffer for zeroing */
770 xfs_daddr_t d; /* disk block address */
771 int error; /* error return value */
772 xfs_fsblock_t firstblock;/* first block allocated in xaction */
773 struct xfs_defer_ops dfops; /* list of freed blocks */
774 xfs_fsblock_t fsbno; /* filesystem block for bno */
775 struct xfs_bmbt_irec map; /* block map output */
776 int nmap; /* number of block maps */
777 int resblks; /* space reservation */
778 struct xfs_trans *tp;
781 * Allocate space to the file, as necessary.
783 while (oblocks < nblocks) {
784 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
786 * Reserve space & log for one extent added to the file.
788 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
789 0, 0, &tp);
790 if (error)
791 return error;
793 * Lock the inode.
795 xfs_ilock(ip, XFS_ILOCK_EXCL);
796 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
798 xfs_defer_init(&dfops, &firstblock);
800 * Allocate blocks to the bitmap file.
802 nmap = 1;
803 error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
804 XFS_BMAPI_METADATA, &firstblock,
805 resblks, &map, &nmap, &dfops);
806 if (!error && nmap < 1)
807 error = -ENOSPC;
808 if (error)
809 goto out_bmap_cancel;
811 * Free any blocks freed up in the transaction, then commit.
813 error = xfs_defer_finish(&tp, &dfops, NULL);
814 if (error)
815 goto out_bmap_cancel;
816 error = xfs_trans_commit(tp);
817 if (error)
818 return error;
820 * Now we need to clear the allocated blocks.
821 * Do this one block per transaction, to keep it simple.
823 for (bno = map.br_startoff, fsbno = map.br_startblock;
824 bno < map.br_startoff + map.br_blockcount;
825 bno++, fsbno++) {
827 * Reserve log for one block zeroing.
829 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
830 0, 0, 0, &tp);
831 if (error)
832 return error;
834 * Lock the bitmap inode.
836 xfs_ilock(ip, XFS_ILOCK_EXCL);
837 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
839 * Get a buffer for the block.
841 d = XFS_FSB_TO_DADDR(mp, fsbno);
842 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
843 mp->m_bsize, 0);
844 if (bp == NULL) {
845 error = -EIO;
846 goto out_trans_cancel;
848 memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
849 xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
851 * Commit the transaction.
853 error = xfs_trans_commit(tp);
854 if (error)
855 return error;
858 * Go on to the next extent, if any.
860 oblocks = map.br_startoff + map.br_blockcount;
863 return 0;
865 out_bmap_cancel:
866 xfs_defer_cancel(&dfops);
867 out_trans_cancel:
868 xfs_trans_cancel(tp);
869 return error;
873 * Visible (exported) functions.
877 * Grow the realtime area of the filesystem.
880 xfs_growfs_rt(
881 xfs_mount_t *mp, /* mount point for filesystem */
882 xfs_growfs_rt_t *in) /* growfs rt input struct */
884 xfs_rtblock_t bmbno; /* bitmap block number */
885 xfs_buf_t *bp; /* temporary buffer */
886 int error; /* error return value */
887 xfs_mount_t *nmp; /* new (fake) mount structure */
888 xfs_rfsblock_t nrblocks; /* new number of realtime blocks */
889 xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
890 xfs_rtblock_t nrextents; /* new number of realtime extents */
891 uint8_t nrextslog; /* new log2 of sb_rextents */
892 xfs_extlen_t nrsumblocks; /* new number of summary blocks */
893 uint nrsumlevels; /* new rt summary levels */
894 uint nrsumsize; /* new size of rt summary, bytes */
895 xfs_sb_t *nsbp; /* new superblock */
896 xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
897 xfs_extlen_t rsumblocks; /* current number of rt summary blks */
898 xfs_sb_t *sbp; /* old superblock */
899 xfs_fsblock_t sumbno; /* summary block number */
901 sbp = &mp->m_sb;
903 * Initial error checking.
905 if (!capable(CAP_SYS_ADMIN))
906 return -EPERM;
907 if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
908 (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
909 (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
910 return -EINVAL;
911 if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
912 return error;
914 * Read in the last block of the device, make sure it exists.
916 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
917 XFS_FSB_TO_BB(mp, nrblocks - 1),
918 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
919 if (error)
920 return error;
921 xfs_buf_relse(bp);
924 * Calculate new parameters. These are the final values to be reached.
926 nrextents = nrblocks;
927 do_div(nrextents, in->extsize);
928 nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
929 nrextslog = xfs_highbit32(nrextents);
930 nrsumlevels = nrextslog + 1;
931 nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
932 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
933 nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
935 * New summary size can't be more than half the size of
936 * the log. This prevents us from getting a log overflow,
937 * since we'll log basically the whole summary file at once.
939 if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
940 return -EINVAL;
942 * Get the old block counts for bitmap and summary inodes.
943 * These can't change since other growfs callers are locked out.
945 rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
946 rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
948 * Allocate space to the bitmap and summary files, as necessary.
950 error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
951 if (error)
952 return error;
953 error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
954 if (error)
955 return error;
957 * Allocate a new (fake) mount/sb.
959 nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
961 * Loop over the bitmap blocks.
962 * We will do everything one bitmap block at a time.
963 * Skip the current block if it is exactly full.
964 * This also deals with the case where there were no rtextents before.
966 for (bmbno = sbp->sb_rbmblocks -
967 ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
968 bmbno < nrbmblocks;
969 bmbno++) {
970 xfs_trans_t *tp;
972 *nmp = *mp;
973 nsbp = &nmp->m_sb;
975 * Calculate new sb and mount fields for this round.
977 nsbp->sb_rextsize = in->extsize;
978 nsbp->sb_rbmblocks = bmbno + 1;
979 nsbp->sb_rblocks =
980 XFS_RTMIN(nrblocks,
981 nsbp->sb_rbmblocks * NBBY *
982 nsbp->sb_blocksize * nsbp->sb_rextsize);
983 nsbp->sb_rextents = nsbp->sb_rblocks;
984 do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
985 ASSERT(nsbp->sb_rextents != 0);
986 nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
987 nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
988 nrsumsize =
989 (uint)sizeof(xfs_suminfo_t) * nrsumlevels *
990 nsbp->sb_rbmblocks;
991 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
992 nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
994 * Start a transaction, get the log reservation.
996 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
997 &tp);
998 if (error)
999 break;
1001 * Lock out other callers by grabbing the bitmap inode lock.
1003 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1004 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1006 * Update the bitmap inode's size.
1008 mp->m_rbmip->i_d.di_size =
1009 nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1010 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1012 * Get the summary inode into the transaction.
1014 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1015 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1017 * Update the summary inode's size.
1019 mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1020 xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1022 * Copy summary data from old to new sizes.
1023 * Do this when the real size (not block-aligned) changes.
1025 if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1026 mp->m_rsumlevels != nmp->m_rsumlevels) {
1027 error = xfs_rtcopy_summary(mp, nmp, tp);
1028 if (error)
1029 goto error_cancel;
1032 * Update superblock fields.
1034 if (nsbp->sb_rextsize != sbp->sb_rextsize)
1035 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1036 nsbp->sb_rextsize - sbp->sb_rextsize);
1037 if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1038 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1039 nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1040 if (nsbp->sb_rblocks != sbp->sb_rblocks)
1041 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1042 nsbp->sb_rblocks - sbp->sb_rblocks);
1043 if (nsbp->sb_rextents != sbp->sb_rextents)
1044 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1045 nsbp->sb_rextents - sbp->sb_rextents);
1046 if (nsbp->sb_rextslog != sbp->sb_rextslog)
1047 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1048 nsbp->sb_rextslog - sbp->sb_rextslog);
1050 * Free new extent.
1052 bp = NULL;
1053 error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1054 nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1055 if (error) {
1056 error_cancel:
1057 xfs_trans_cancel(tp);
1058 break;
1061 * Mark more blocks free in the superblock.
1063 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1064 nsbp->sb_rextents - sbp->sb_rextents);
1066 * Update mp values into the real mp structure.
1068 mp->m_rsumlevels = nrsumlevels;
1069 mp->m_rsumsize = nrsumsize;
1071 error = xfs_trans_commit(tp);
1072 if (error)
1073 break;
1077 * Free the fake mp structure.
1079 kmem_free(nmp);
1081 return error;
1085 * Allocate an extent in the realtime subvolume, with the usual allocation
1086 * parameters. The length units are all in realtime extents, as is the
1087 * result block number.
1089 int /* error */
1090 xfs_rtallocate_extent(
1091 xfs_trans_t *tp, /* transaction pointer */
1092 xfs_rtblock_t bno, /* starting block number to allocate */
1093 xfs_extlen_t minlen, /* minimum length to allocate */
1094 xfs_extlen_t maxlen, /* maximum length to allocate */
1095 xfs_extlen_t *len, /* out: actual length allocated */
1096 xfs_alloctype_t type, /* allocation type XFS_ALLOCTYPE... */
1097 int wasdel, /* was a delayed allocation extent */
1098 xfs_extlen_t prod, /* extent product factor */
1099 xfs_rtblock_t *rtblock) /* out: start block allocated */
1101 xfs_mount_t *mp = tp->t_mountp;
1102 int error; /* error value */
1103 xfs_rtblock_t r; /* result allocated block */
1104 xfs_fsblock_t sb; /* summary file block number */
1105 xfs_buf_t *sumbp; /* summary file block buffer */
1107 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1108 ASSERT(minlen > 0 && minlen <= maxlen);
1111 * If prod is set then figure out what to do to minlen and maxlen.
1113 if (prod > 1) {
1114 xfs_extlen_t i;
1116 if ((i = maxlen % prod))
1117 maxlen -= i;
1118 if ((i = minlen % prod))
1119 minlen += prod - i;
1120 if (maxlen < minlen) {
1121 *rtblock = NULLRTBLOCK;
1122 return 0;
1126 sumbp = NULL;
1128 * Allocate by size, or near another block, or exactly at some block.
1130 switch (type) {
1131 case XFS_ALLOCTYPE_ANY_AG:
1132 error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1133 &sumbp, &sb, prod, &r);
1134 break;
1135 case XFS_ALLOCTYPE_NEAR_BNO:
1136 error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1137 len, &sumbp, &sb, prod, &r);
1138 break;
1139 case XFS_ALLOCTYPE_THIS_BNO:
1140 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen,
1141 len, &sumbp, &sb, prod, &r);
1142 break;
1143 default:
1144 error = -EIO;
1145 ASSERT(0);
1147 if (error)
1148 return error;
1151 * If it worked, update the superblock.
1153 if (r != NULLRTBLOCK) {
1154 long slen = (long)*len;
1156 ASSERT(*len >= minlen && *len <= maxlen);
1157 if (wasdel)
1158 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1159 else
1160 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1162 *rtblock = r;
1163 return 0;
1167 * Initialize realtime fields in the mount structure.
1169 int /* error */
1170 xfs_rtmount_init(
1171 struct xfs_mount *mp) /* file system mount structure */
1173 struct xfs_buf *bp; /* buffer for last block of subvolume */
1174 struct xfs_sb *sbp; /* filesystem superblock copy in mount */
1175 xfs_daddr_t d; /* address of last block of subvolume */
1176 int error;
1178 sbp = &mp->m_sb;
1179 if (sbp->sb_rblocks == 0)
1180 return 0;
1181 if (mp->m_rtdev_targp == NULL) {
1182 xfs_warn(mp,
1183 "Filesystem has a realtime volume, use rtdev=device option");
1184 return -ENODEV;
1186 mp->m_rsumlevels = sbp->sb_rextslog + 1;
1187 mp->m_rsumsize =
1188 (uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1189 sbp->sb_rbmblocks;
1190 mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1191 mp->m_rbmip = mp->m_rsumip = NULL;
1193 * Check that the realtime section is an ok size.
1195 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1196 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1197 xfs_warn(mp, "realtime mount -- %llu != %llu",
1198 (unsigned long long) XFS_BB_TO_FSB(mp, d),
1199 (unsigned long long) mp->m_sb.sb_rblocks);
1200 return -EFBIG;
1202 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1203 d - XFS_FSB_TO_BB(mp, 1),
1204 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1205 if (error) {
1206 xfs_warn(mp, "realtime device size check failed");
1207 return error;
1209 xfs_buf_relse(bp);
1210 return 0;
1214 * Get the bitmap and summary inodes into the mount structure
1215 * at mount time.
1217 int /* error */
1218 xfs_rtmount_inodes(
1219 xfs_mount_t *mp) /* file system mount structure */
1221 int error; /* error return value */
1222 xfs_sb_t *sbp;
1224 sbp = &mp->m_sb;
1225 if (sbp->sb_rbmino == NULLFSINO)
1226 return 0;
1227 error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1228 if (error)
1229 return error;
1230 ASSERT(mp->m_rbmip != NULL);
1231 ASSERT(sbp->sb_rsumino != NULLFSINO);
1232 error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1233 if (error) {
1234 IRELE(mp->m_rbmip);
1235 return error;
1237 ASSERT(mp->m_rsumip != NULL);
1238 return 0;
1241 void
1242 xfs_rtunmount_inodes(
1243 struct xfs_mount *mp)
1245 if (mp->m_rbmip)
1246 IRELE(mp->m_rbmip);
1247 if (mp->m_rsumip)
1248 IRELE(mp->m_rsumip);
1252 * Pick an extent for allocation at the start of a new realtime file.
1253 * Use the sequence number stored in the atime field of the bitmap inode.
1254 * Translate this to a fraction of the rtextents, and return the product
1255 * of rtextents and the fraction.
1256 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1258 int /* error */
1259 xfs_rtpick_extent(
1260 xfs_mount_t *mp, /* file system mount point */
1261 xfs_trans_t *tp, /* transaction pointer */
1262 xfs_extlen_t len, /* allocation length (rtextents) */
1263 xfs_rtblock_t *pick) /* result rt extent */
1265 xfs_rtblock_t b; /* result block */
1266 int log2; /* log of sequence number */
1267 __uint64_t resid; /* residual after log removed */
1268 __uint64_t seq; /* sequence number of file creation */
1269 __uint64_t *seqp; /* pointer to seqno in inode */
1271 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1273 seqp = (__uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1274 if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1275 mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1276 *seqp = 0;
1278 seq = *seqp;
1279 if ((log2 = xfs_highbit64(seq)) == -1)
1280 b = 0;
1281 else {
1282 resid = seq - (1ULL << log2);
1283 b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1284 (log2 + 1);
1285 if (b >= mp->m_sb.sb_rextents)
1286 b = do_mod(b, mp->m_sb.sb_rextents);
1287 if (b + len > mp->m_sb.sb_rextents)
1288 b = mp->m_sb.sb_rextents - len;
1290 *seqp = seq + 1;
1291 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1292 *pick = b;
1293 return 0;