?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
s390/uaccess: fix whitespace damage
[linux-2.6/btrfs-unstable.git] / fs / xfs / xfs_rtalloc.c
blob3938b37d1043bb6fd98879fa4783b6bbec8cfef6
1 /*
2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
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.
8 *
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.
13 *
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
17 */
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_inode.h"
27 #include "xfs_bmap.h"
28 #include "xfs_bmap_util.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_alloc.h"
31 #include "xfs_error.h"
32 #include "xfs_trans.h"
33 #include "xfs_trans_space.h"
34 #include "xfs_trace.h"
35 #include "xfs_buf.h"
36 #include "xfs_icache.h"
37 #include "xfs_rtalloc.h"
38
39
40 /*
41 * Read and return the summary information for a given extent size,
42 * bitmap block combination.
43 * Keeps track of a current summary block, so we don't keep reading
44 * it from the buffer cache.
45 */
46 static int
47 xfs_rtget_summary(
48 xfs_mount_t *mp, /* file system mount structure */
49 xfs_trans_t *tp, /* transaction pointer */
50 int log, /* log2 of extent size */
51 xfs_rtblock_t bbno, /* bitmap block number */
52 xfs_buf_t **rbpp, /* in/out: summary block buffer */
53 xfs_fsblock_t *rsb, /* in/out: summary block number */
54 xfs_suminfo_t *sum) /* out: summary info for this block */
55 {
56 return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
57 }
58
59 /*
60 * Return whether there are any free extents in the size range given
61 * by low and high, for the bitmap block bbno.
62 */
63 STATIC int /* error */
64 xfs_rtany_summary(
65 xfs_mount_t *mp, /* file system mount structure */
66 xfs_trans_t *tp, /* transaction pointer */
67 int low, /* low log2 extent size */
68 int high, /* high log2 extent size */
69 xfs_rtblock_t bbno, /* bitmap block number */
70 xfs_buf_t **rbpp, /* in/out: summary block buffer */
71 xfs_fsblock_t *rsb, /* in/out: summary block number */
72 int *stat) /* out: any good extents here? */
73 {
74 int error; /* error value */
75 int log; /* loop counter, log2 of ext. size */
76 xfs_suminfo_t sum; /* summary data */
77
78 /*
79 * Loop over logs of extent sizes. Order is irrelevant.
80 */
81 for (log = low; log <= high; log++) {
82 /*
83 * Get one summary datum.
84 */
85 error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
86 if (error) {
87 return error;
88 }
89 /*
90 * If there are any, return success.
91 */
92 if (sum) {
93 *stat = 1;
94 return 0;
95 }
96 }
97 /*
98 * Found nothing, return failure.
99 */
100 *stat = 0;
101 return 0;
102 }
103
104
105 /*
106 * Copy and transform the summary file, given the old and new
107 * parameters in the mount structures.
108 */
109 STATIC int /* error */
110 xfs_rtcopy_summary(
111 xfs_mount_t *omp, /* old file system mount point */
112 xfs_mount_t *nmp, /* new file system mount point */
113 xfs_trans_t *tp) /* transaction pointer */
114 {
115 xfs_rtblock_t bbno; /* bitmap block number */
116 xfs_buf_t *bp; /* summary buffer */
117 int error; /* error return value */
118 int log; /* summary level number (log length) */
119 xfs_suminfo_t sum; /* summary data */
120 xfs_fsblock_t sumbno; /* summary block number */
121
122 bp = NULL;
123 for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
124 for (bbno = omp->m_sb.sb_rbmblocks - 1;
125 (xfs_srtblock_t)bbno >= 0;
126 bbno--) {
127 error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
128 &sumbno, &sum);
129 if (error)
130 return error;
131 if (sum == 0)
132 continue;
133 error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
134 &bp, &sumbno);
135 if (error)
136 return error;
137 error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
138 &bp, &sumbno);
139 if (error)
140 return error;
141 ASSERT(sum > 0);
142 }
143 }
144 return 0;
145 }
146 /*
147 * Mark an extent specified by start and len allocated.
148 * Updates all the summary information as well as the bitmap.
149 */
150 STATIC int /* error */
151 xfs_rtallocate_range(
152 xfs_mount_t *mp, /* file system mount point */
153 xfs_trans_t *tp, /* transaction pointer */
154 xfs_rtblock_t start, /* start block to allocate */
155 xfs_extlen_t len, /* length to allocate */
156 xfs_buf_t **rbpp, /* in/out: summary block buffer */
157 xfs_fsblock_t *rsb) /* in/out: summary block number */
158 {
159 xfs_rtblock_t end; /* end of the allocated extent */
160 int error; /* error value */
161 xfs_rtblock_t postblock = 0; /* first block allocated > end */
162 xfs_rtblock_t preblock = 0; /* first block allocated < start */
163
164 end = start + len - 1;
165 /*
166 * Assume we're allocating out of the middle of a free extent.
167 * We need to find the beginning and end of the extent so we can
168 * properly update the summary.
169 */
170 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
171 if (error) {
172 return error;
173 }
174 /*
175 * Find the next allocated block (end of free extent).
176 */
177 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
178 &postblock);
179 if (error) {
180 return error;
181 }
182 /*
183 * Decrement the summary information corresponding to the entire
184 * (old) free extent.
185 */
186 error = xfs_rtmodify_summary(mp, tp,
187 XFS_RTBLOCKLOG(postblock + 1 - preblock),
188 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
189 if (error) {
190 return error;
191 }
192 /*
193 * If there are blocks not being allocated at the front of the
194 * old extent, add summary data for them to be free.
195 */
196 if (preblock < start) {
197 error = xfs_rtmodify_summary(mp, tp,
198 XFS_RTBLOCKLOG(start - preblock),
199 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
200 if (error) {
201 return error;
202 }
203 }
204 /*
205 * If there are blocks not being allocated at the end of the
206 * old extent, add summary data for them to be free.
207 */
208 if (postblock > end) {
209 error = xfs_rtmodify_summary(mp, tp,
210 XFS_RTBLOCKLOG(postblock - end),
211 XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
212 if (error) {
213 return error;
214 }
215 }
216 /*
217 * Modify the bitmap to mark this extent allocated.
218 */
219 error = xfs_rtmodify_range(mp, tp, start, len, 0);
220 return error;
221 }
222
223 /*
224 * Attempt to allocate an extent minlen<=len<=maxlen starting from
225 * bitmap block bbno. If we don't get maxlen then use prod to trim
226 * the length, if given. Returns error; returns starting block in *rtblock.
227 * The lengths are all in rtextents.
228 */
229 STATIC int /* error */
230 xfs_rtallocate_extent_block(
231 xfs_mount_t *mp, /* file system mount point */
232 xfs_trans_t *tp, /* transaction pointer */
233 xfs_rtblock_t bbno, /* bitmap block number */
234 xfs_extlen_t minlen, /* minimum length to allocate */
235 xfs_extlen_t maxlen, /* maximum length to allocate */
236 xfs_extlen_t *len, /* out: actual length allocated */
237 xfs_rtblock_t *nextp, /* out: next block to try */
238 xfs_buf_t **rbpp, /* in/out: summary block buffer */
239 xfs_fsblock_t *rsb, /* in/out: summary block number */
240 xfs_extlen_t prod, /* extent product factor */
241 xfs_rtblock_t *rtblock) /* out: start block allocated */
242 {
243 xfs_rtblock_t besti; /* best rtblock found so far */
244 xfs_rtblock_t bestlen; /* best length found so far */
245 xfs_rtblock_t end; /* last rtblock in chunk */
246 int error; /* error value */
247 xfs_rtblock_t i; /* current rtblock trying */
248 xfs_rtblock_t next; /* next rtblock to try */
249 int stat; /* status from internal calls */
250
251 /*
252 * Loop over all the extents starting in this bitmap block,
253 * looking for one that's long enough.
254 */
255 for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
256 end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
257 i <= end;
258 i++) {
259 /*
260 * See if there's a free extent of maxlen starting at i.
261 * If it's not so then next will contain the first non-free.
262 */
263 error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
264 if (error) {
265 return error;
266 }
267 if (stat) {
268 /*
269 * i for maxlen is all free, allocate and return that.
270 */
271 error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
272 rsb);
273 if (error) {
274 return error;
275 }
276 *len = maxlen;
277 *rtblock = i;
278 return 0;
279 }
280 /*
281 * In the case where we have a variable-sized allocation
282 * request, figure out how big this free piece is,
283 * and if it's big enough for the minimum, and the best
284 * so far, remember it.
285 */
286 if (minlen < maxlen) {
287 xfs_rtblock_t thislen; /* this extent size */
288
289 thislen = next - i;
290 if (thislen >= minlen && thislen > bestlen) {
291 besti = i;
292 bestlen = thislen;
293 }
294 }
295 /*
296 * If not done yet, find the start of the next free space.
297 */
298 if (next < end) {
299 error = xfs_rtfind_forw(mp, tp, next, end, &i);
300 if (error) {
301 return error;
302 }
303 } else
304 break;
305 }
306 /*
307 * Searched the whole thing & didn't find a maxlen free extent.
308 */
309 if (minlen < maxlen && besti != -1) {
310 xfs_extlen_t p; /* amount to trim length by */
311
312 /*
313 * If size should be a multiple of prod, make that so.
314 */
315 if (prod > 1 && (p = do_mod(bestlen, prod)))
316 bestlen -= p;
317 /*
318 * Allocate besti for bestlen & return that.
319 */
320 error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
321 if (error) {
322 return error;
323 }
324 *len = bestlen;
325 *rtblock = besti;
326 return 0;
327 }
328 /*
329 * Allocation failed. Set *nextp to the next block to try.
330 */
331 *nextp = next;
332 *rtblock = NULLRTBLOCK;
333 return 0;
334 }
335
336 /*
337 * Allocate an extent of length minlen<=len<=maxlen, starting at block
338 * bno. If we don't get maxlen then use prod to trim the length, if given.
339 * Returns error; returns starting block in *rtblock.
340 * The lengths are all in rtextents.
341 */
342 STATIC int /* error */
343 xfs_rtallocate_extent_exact(
344 xfs_mount_t *mp, /* file system mount point */
345 xfs_trans_t *tp, /* transaction pointer */
346 xfs_rtblock_t bno, /* starting block number to allocate */
347 xfs_extlen_t minlen, /* minimum length to allocate */
348 xfs_extlen_t maxlen, /* maximum length to allocate */
349 xfs_extlen_t *len, /* out: actual length allocated */
350 xfs_buf_t **rbpp, /* in/out: summary block buffer */
351 xfs_fsblock_t *rsb, /* in/out: summary block number */
352 xfs_extlen_t prod, /* extent product factor */
353 xfs_rtblock_t *rtblock) /* out: start block allocated */
354 {
355 int error; /* error value */
356 xfs_extlen_t i; /* extent length trimmed due to prod */
357 int isfree; /* extent is free */
358 xfs_rtblock_t next; /* next block to try (dummy) */
359
360 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
361 /*
362 * Check if the range in question (for maxlen) is free.
363 */
364 error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
365 if (error) {
366 return error;
367 }
368 if (isfree) {
369 /*
370 * If it is, allocate it and return success.
371 */
372 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
373 if (error) {
374 return error;
375 }
376 *len = maxlen;
377 *rtblock = bno;
378 return 0;
379 }
380 /*
381 * If not, allocate what there is, if it's at least minlen.
382 */
383 maxlen = next - bno;
384 if (maxlen < minlen) {
385 /*
386 * Failed, return failure status.
387 */
388 *rtblock = NULLRTBLOCK;
389 return 0;
390 }
391 /*
392 * Trim off tail of extent, if prod is specified.
393 */
394 if (prod > 1 && (i = maxlen % prod)) {
395 maxlen -= i;
396 if (maxlen < minlen) {
397 /*
398 * Now we can't do it, return failure status.
399 */
400 *rtblock = NULLRTBLOCK;
401 return 0;
402 }
403 }
404 /*
405 * Allocate what we can and return it.
406 */
407 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
408 if (error) {
409 return error;
410 }
411 *len = maxlen;
412 *rtblock = bno;
413 return 0;
414 }
415
416 /*
417 * Allocate an extent of length minlen<=len<=maxlen, starting as near
418 * to bno as possible. If we don't get maxlen then use prod to trim
419 * the length, if given. The lengths are all in rtextents.
420 */
421 STATIC int /* error */
422 xfs_rtallocate_extent_near(
423 xfs_mount_t *mp, /* file system mount point */
424 xfs_trans_t *tp, /* transaction pointer */
425 xfs_rtblock_t bno, /* starting block number to allocate */
426 xfs_extlen_t minlen, /* minimum length to allocate */
427 xfs_extlen_t maxlen, /* maximum length to allocate */
428 xfs_extlen_t *len, /* out: actual length allocated */
429 xfs_buf_t **rbpp, /* in/out: summary block buffer */
430 xfs_fsblock_t *rsb, /* in/out: summary block number */
431 xfs_extlen_t prod, /* extent product factor */
432 xfs_rtblock_t *rtblock) /* out: start block allocated */
433 {
434 int any; /* any useful extents from summary */
435 xfs_rtblock_t bbno; /* bitmap block number */
436 int error; /* error value */
437 int i; /* bitmap block offset (loop control) */
438 int j; /* secondary loop control */
439 int log2len; /* log2 of minlen */
440 xfs_rtblock_t n; /* next block to try */
441 xfs_rtblock_t r; /* result block */
442
443 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
444 /*
445 * If the block number given is off the end, silently set it to
446 * the last block.
447 */
448 if (bno >= mp->m_sb.sb_rextents)
449 bno = mp->m_sb.sb_rextents - 1;
450 /*
451 * Try the exact allocation first.
452 */
453 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
454 rbpp, rsb, prod, &r);
455 if (error) {
456 return error;
457 }
458 /*
459 * If the exact allocation worked, return that.
460 */
461 if (r != NULLRTBLOCK) {
462 *rtblock = r;
463 return 0;
464 }
465 bbno = XFS_BITTOBLOCK(mp, bno);
466 i = 0;
467 ASSERT(minlen != 0);
468 log2len = xfs_highbit32(minlen);
469 /*
470 * Loop over all bitmap blocks (bbno + i is current block).
471 */
472 for (;;) {
473 /*
474 * Get summary information of extents of all useful levels
475 * starting in this bitmap block.
476 */
477 error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
478 bbno + i, rbpp, rsb, &any);
479 if (error) {
480 return error;
481 }
482 /*
483 * If there are any useful extents starting here, try
484 * allocating one.
485 */
486 if (any) {
487 /*
488 * On the positive side of the starting location.
489 */
490 if (i >= 0) {
491 /*
492 * Try to allocate an extent starting in
493 * this block.
494 */
495 error = xfs_rtallocate_extent_block(mp, tp,
496 bbno + i, minlen, maxlen, len, &n, rbpp,
497 rsb, prod, &r);
498 if (error) {
499 return error;
500 }
501 /*
502 * If it worked, return it.
503 */
504 if (r != NULLRTBLOCK) {
505 *rtblock = r;
506 return 0;
507 }
508 }
509 /*
510 * On the negative side of the starting location.
511 */
512 else { /* i < 0 */
513 /*
514 * Loop backwards through the bitmap blocks from
515 * the starting point-1 up to where we are now.
516 * There should be an extent which ends in this
517 * bitmap block and is long enough.
518 */
519 for (j = -1; j > i; j--) {
520 /*
521 * Grab the summary information for
522 * this bitmap block.
523 */
524 error = xfs_rtany_summary(mp, tp,
525 log2len, mp->m_rsumlevels - 1,
526 bbno + j, rbpp, rsb, &any);
527 if (error) {
528 return error;
529 }
530 /*
531 * If there's no extent given in the
532 * summary that means the extent we
533 * found must carry over from an
534 * earlier block. If there is an
535 * extent given, we've already tried
536 * that allocation, don't do it again.
537 */
538 if (any)
539 continue;
540 error = xfs_rtallocate_extent_block(mp,
541 tp, bbno + j, minlen, maxlen,
542 len, &n, rbpp, rsb, prod, &r);
543 if (error) {
544 return error;
545 }
546 /*
547 * If it works, return the extent.
548 */
549 if (r != NULLRTBLOCK) {
550 *rtblock = r;
551 return 0;
552 }
553 }
554 /*
555 * There weren't intervening bitmap blocks
556 * with a long enough extent, or the
557 * allocation didn't work for some reason
558 * (i.e. it's a little * too short).
559 * Try to allocate from the summary block
560 * that we found.
561 */
562 error = xfs_rtallocate_extent_block(mp, tp,
563 bbno + i, minlen, maxlen, len, &n, rbpp,
564 rsb, prod, &r);
565 if (error) {
566 return error;
567 }
568 /*
569 * If it works, return the extent.
570 */
571 if (r != NULLRTBLOCK) {
572 *rtblock = r;
573 return 0;
574 }
575 }
576 }
577 /*
578 * Loop control. If we were on the positive side, and there's
579 * still more blocks on the negative side, go there.
580 */
581 if (i > 0 && (int)bbno - i >= 0)
582 i = -i;
583 /*
584 * If positive, and no more negative, but there are more
585 * positive, go there.
586 */
587 else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
588 i++;
589 /*
590 * If negative or 0 (just started), and there are positive
591 * blocks to go, go there. The 0 case moves to block 1.
592 */
593 else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
594 i = 1 - i;
595 /*
596 * If negative or 0 and there are more negative blocks,
597 * go there.
598 */
599 else if (i <= 0 && (int)bbno + i > 0)
600 i--;
601 /*
602 * Must be done. Return failure.
603 */
604 else
605 break;
606 }
607 *rtblock = NULLRTBLOCK;
608 return 0;
609 }
610
611 /*
612 * Allocate an extent of length minlen<=len<=maxlen, with no position
613 * specified. If we don't get maxlen then use prod to trim
614 * the length, if given. The lengths are all in rtextents.
615 */
616 STATIC int /* error */
617 xfs_rtallocate_extent_size(
618 xfs_mount_t *mp, /* file system mount point */
619 xfs_trans_t *tp, /* transaction pointer */
620 xfs_extlen_t minlen, /* minimum length to allocate */
621 xfs_extlen_t maxlen, /* maximum length to allocate */
622 xfs_extlen_t *len, /* out: actual length allocated */
623 xfs_buf_t **rbpp, /* in/out: summary block buffer */
624 xfs_fsblock_t *rsb, /* in/out: summary block number */
625 xfs_extlen_t prod, /* extent product factor */
626 xfs_rtblock_t *rtblock) /* out: start block allocated */
627 {
628 int error; /* error value */
629 int i; /* bitmap block number */
630 int l; /* level number (loop control) */
631 xfs_rtblock_t n; /* next block to be tried */
632 xfs_rtblock_t r; /* result block number */
633 xfs_suminfo_t sum; /* summary information for extents */
634
635 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
636 ASSERT(maxlen != 0);
637
638 /*
639 * Loop over all the levels starting with maxlen.
640 * At each level, look at all the bitmap blocks, to see if there
641 * are extents starting there that are long enough (>= maxlen).
642 * Note, only on the initial level can the allocation fail if
643 * the summary says there's an extent.
644 */
645 for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
646 /*
647 * Loop over all the bitmap blocks.
648 */
649 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
650 /*
651 * Get the summary for this level/block.
652 */
653 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
654 &sum);
655 if (error) {
656 return error;
657 }
658 /*
659 * Nothing there, on to the next block.
660 */
661 if (!sum)
662 continue;
663 /*
664 * Try allocating the extent.
665 */
666 error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
667 maxlen, len, &n, rbpp, rsb, prod, &r);
668 if (error) {
669 return error;
670 }
671 /*
672 * If it worked, return that.
673 */
674 if (r != NULLRTBLOCK) {
675 *rtblock = r;
676 return 0;
677 }
678 /*
679 * If the "next block to try" returned from the
680 * allocator is beyond the next bitmap block,
681 * skip to that bitmap block.
682 */
683 if (XFS_BITTOBLOCK(mp, n) > i + 1)
684 i = XFS_BITTOBLOCK(mp, n) - 1;
685 }
686 }
687 /*
688 * Didn't find any maxlen blocks. Try smaller ones, unless
689 * we're asking for a fixed size extent.
690 */
691 if (minlen > --maxlen) {
692 *rtblock = NULLRTBLOCK;
693 return 0;
694 }
695 ASSERT(minlen != 0);
696 ASSERT(maxlen != 0);
697
698 /*
699 * Loop over sizes, from maxlen down to minlen.
700 * This time, when we do the allocations, allow smaller ones
701 * to succeed.
702 */
703 for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
704 /*
705 * Loop over all the bitmap blocks, try an allocation
706 * starting in that block.
707 */
708 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
709 /*
710 * Get the summary information for this level/block.
711 */
712 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
713 &sum);
714 if (error) {
715 return error;
716 }
717 /*
718 * If nothing there, go on to next.
719 */
720 if (!sum)
721 continue;
722 /*
723 * Try the allocation. Make sure the specified
724 * minlen/maxlen are in the possible range for
725 * this summary level.
726 */
727 error = xfs_rtallocate_extent_block(mp, tp, i,
728 XFS_RTMAX(minlen, 1 << l),
729 XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
730 len, &n, rbpp, rsb, prod, &r);
731 if (error) {
732 return error;
733 }
734 /*
735 * If it worked, return that extent.
736 */
737 if (r != NULLRTBLOCK) {
738 *rtblock = r;
739 return 0;
740 }
741 /*
742 * If the "next block to try" returned from the
743 * allocator is beyond the next bitmap block,
744 * skip to that bitmap block.
745 */
746 if (XFS_BITTOBLOCK(mp, n) > i + 1)
747 i = XFS_BITTOBLOCK(mp, n) - 1;
748 }
749 }
750 /*
751 * Got nothing, return failure.
752 */
753 *rtblock = NULLRTBLOCK;
754 return 0;
755 }
756
757 /*
758 * Allocate space to the bitmap or summary file, and zero it, for growfs.
759 */
760 STATIC int
761 xfs_growfs_rt_alloc(
762 struct xfs_mount *mp, /* file system mount point */
763 xfs_extlen_t oblocks, /* old count of blocks */
764 xfs_extlen_t nblocks, /* new count of blocks */
765 struct xfs_inode *ip) /* inode (bitmap/summary) */
766 {
767 xfs_fileoff_t bno; /* block number in file */
768 struct xfs_buf *bp; /* temporary buffer for zeroing */
769 xfs_daddr_t d; /* disk block address */
770 int error; /* error return value */
771 xfs_fsblock_t firstblock;/* first block allocated in xaction */
772 struct xfs_bmap_free flist; /* list of freed blocks */
773 xfs_fsblock_t fsbno; /* filesystem block for bno */
774 struct xfs_bmbt_irec map; /* block map output */
775 int nmap; /* number of block maps */
776 int resblks; /* space reservation */
777 struct xfs_trans *tp;
778
779 /*
780 * Allocate space to the file, as necessary.
781 */
782 while (oblocks < nblocks) {
783 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
784 /*
785 * Reserve space & log for one extent added to the file.
786 */
787 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
788 0, 0, &tp);
789 if (error)
790 return error;
791 /*
792 * Lock the inode.
793 */
794 xfs_ilock(ip, XFS_ILOCK_EXCL);
795 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
796
797 xfs_bmap_init(&flist, &firstblock);
798 /*
799 * Allocate blocks to the bitmap file.
800 */
801 nmap = 1;
802 error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
803 XFS_BMAPI_METADATA, &firstblock,
804 resblks, &map, &nmap, &flist);
805 if (!error && nmap < 1)
806 error = -ENOSPC;
807 if (error)
808 goto out_bmap_cancel;
809 /*
810 * Free any blocks freed up in the transaction, then commit.
811 */
812 error = xfs_bmap_finish(&tp, &flist, NULL);
813 if (error)
814 goto out_bmap_cancel;
815 error = xfs_trans_commit(tp);
816 if (error)
817 return error;
818 /*
819 * Now we need to clear the allocated blocks.
820 * Do this one block per transaction, to keep it simple.
821 */
822 for (bno = map.br_startoff, fsbno = map.br_startblock;
823 bno < map.br_startoff + map.br_blockcount;
824 bno++, fsbno++) {
825 /*
826 * Reserve log for one block zeroing.
827 */
828 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
829 0, 0, 0, &tp);
830 if (error)
831 return error;
832 /*
833 * Lock the bitmap inode.
834 */
835 xfs_ilock(ip, XFS_ILOCK_EXCL);
836 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
837 /*
838 * Get a buffer for the block.
839 */
840 d = XFS_FSB_TO_DADDR(mp, fsbno);
841 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
842 mp->m_bsize, 0);
843 if (bp == NULL) {
844 error = -EIO;
845 goto out_trans_cancel;
846 }
847 memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
848 xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
849 /*
850 * Commit the transaction.
851 */
852 error = xfs_trans_commit(tp);
853 if (error)
854 return error;
855 }
856 /*
857 * Go on to the next extent, if any.
858 */
859 oblocks = map.br_startoff + map.br_blockcount;
860 }
861
862 return 0;
863
864 out_bmap_cancel:
865 xfs_bmap_cancel(&flist);
866 out_trans_cancel:
867 xfs_trans_cancel(tp);
868 return error;
869 }
870
871 /*
872 * Visible (exported) functions.
873 */
874
875 /*
876 * Grow the realtime area of the filesystem.
877 */
878 int
879 xfs_growfs_rt(
880 xfs_mount_t *mp, /* mount point for filesystem */
881 xfs_growfs_rt_t *in) /* growfs rt input struct */
882 {
883 xfs_rtblock_t bmbno; /* bitmap block number */
884 xfs_buf_t *bp; /* temporary buffer */
885 int error; /* error return value */
886 xfs_mount_t *nmp; /* new (fake) mount structure */
887 xfs_rfsblock_t nrblocks; /* new number of realtime blocks */
888 xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
889 xfs_rtblock_t nrextents; /* new number of realtime extents */
890 uint8_t nrextslog; /* new log2 of sb_rextents */
891 xfs_extlen_t nrsumblocks; /* new number of summary blocks */
892 uint nrsumlevels; /* new rt summary levels */
893 uint nrsumsize; /* new size of rt summary, bytes */
894 xfs_sb_t *nsbp; /* new superblock */
895 xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
896 xfs_extlen_t rsumblocks; /* current number of rt summary blks */
897 xfs_sb_t *sbp; /* old superblock */
898 xfs_fsblock_t sumbno; /* summary block number */
899
900 sbp = &mp->m_sb;
901 /*
902 * Initial error checking.
903 */
904 if (!capable(CAP_SYS_ADMIN))
905 return -EPERM;
906 if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
907 (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
908 (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
909 return -EINVAL;
910 if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
911 return error;
912 /*
913 * Read in the last block of the device, make sure it exists.
914 */
915 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
916 XFS_FSB_TO_BB(mp, nrblocks - 1),
917 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
918 if (error)
919 return error;
920 xfs_buf_relse(bp);
921
922 /*
923 * Calculate new parameters. These are the final values to be reached.
924 */
925 nrextents = nrblocks;
926 do_div(nrextents, in->extsize);
927 nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
928 nrextslog = xfs_highbit32(nrextents);
929 nrsumlevels = nrextslog + 1;
930 nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
931 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
932 nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
933 /*
934 * New summary size can't be more than half the size of
935 * the log. This prevents us from getting a log overflow,
936 * since we'll log basically the whole summary file at once.
937 */
938 if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
939 return -EINVAL;
940 /*
941 * Get the old block counts for bitmap and summary inodes.
942 * These can't change since other growfs callers are locked out.
943 */
944 rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
945 rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
946 /*
947 * Allocate space to the bitmap and summary files, as necessary.
948 */
949 error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
950 if (error)
951 return error;
952 error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
953 if (error)
954 return error;
955 /*
956 * Allocate a new (fake) mount/sb.
957 */
958 nmp = kmem_alloc(sizeof(*nmp), KM_SLEEP);
959 /*
960 * Loop over the bitmap blocks.
961 * We will do everything one bitmap block at a time.
962 * Skip the current block if it is exactly full.
963 * This also deals with the case where there were no rtextents before.
964 */
965 for (bmbno = sbp->sb_rbmblocks -
966 ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
967 bmbno < nrbmblocks;
968 bmbno++) {
969 xfs_trans_t *tp;
970
971 *nmp = *mp;
972 nsbp = &nmp->m_sb;
973 /*
974 * Calculate new sb and mount fields for this round.
975 */
976 nsbp->sb_rextsize = in->extsize;
977 nsbp->sb_rbmblocks = bmbno + 1;
978 nsbp->sb_rblocks =
979 XFS_RTMIN(nrblocks,
980 nsbp->sb_rbmblocks * NBBY *
981 nsbp->sb_blocksize * nsbp->sb_rextsize);
982 nsbp->sb_rextents = nsbp->sb_rblocks;
983 do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
984 ASSERT(nsbp->sb_rextents != 0);
985 nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
986 nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
987 nrsumsize =
988 (uint)sizeof(xfs_suminfo_t) * nrsumlevels *
989 nsbp->sb_rbmblocks;
990 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
991 nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
992 /*
993 * Start a transaction, get the log reservation.
994 */
995 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
996 &tp);
997 if (error)
998 break;
999 /*
1000 * Lock out other callers by grabbing the bitmap inode lock.
1001 */
1002 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1003 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1004 /*
1005 * Update the bitmap inode's size.
1006 */
1007 mp->m_rbmip->i_d.di_size =
1008 nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1009 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1010 /*
1011 * Get the summary inode into the transaction.
1012 */
1013 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1014 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1015 /*
1016 * Update the summary inode's size.
1017 */
1018 mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1019 xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1020 /*
1021 * Copy summary data from old to new sizes.
1022 * Do this when the real size (not block-aligned) changes.
1023 */
1024 if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1025 mp->m_rsumlevels != nmp->m_rsumlevels) {
1026 error = xfs_rtcopy_summary(mp, nmp, tp);
1027 if (error)
1028 goto error_cancel;
1029 }
1030 /*
1031 * Update superblock fields.
1032 */
1033 if (nsbp->sb_rextsize != sbp->sb_rextsize)
1034 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1035 nsbp->sb_rextsize - sbp->sb_rextsize);
1036 if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1037 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1038 nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1039 if (nsbp->sb_rblocks != sbp->sb_rblocks)
1040 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1041 nsbp->sb_rblocks - sbp->sb_rblocks);
1042 if (nsbp->sb_rextents != sbp->sb_rextents)
1043 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1044 nsbp->sb_rextents - sbp->sb_rextents);
1045 if (nsbp->sb_rextslog != sbp->sb_rextslog)
1046 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1047 nsbp->sb_rextslog - sbp->sb_rextslog);
1048 /*
1049 * Free new extent.
1050 */
1051 bp = NULL;
1052 error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1053 nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1054 if (error) {
1055 error_cancel:
1056 xfs_trans_cancel(tp);
1057 break;
1058 }
1059 /*
1060 * Mark more blocks free in the superblock.
1061 */
1062 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1063 nsbp->sb_rextents - sbp->sb_rextents);
1064 /*
1065 * Update mp values into the real mp structure.
1066 */
1067 mp->m_rsumlevels = nrsumlevels;
1068 mp->m_rsumsize = nrsumsize;
1069
1070 error = xfs_trans_commit(tp);
1071 if (error)
1072 break;
1073 }
1074
1075 /*
1076 * Free the fake mp structure.
1077 */
1078 kmem_free(nmp);
1079
1080 return error;
1081 }
1082
1083 /*
1084 * Allocate an extent in the realtime subvolume, with the usual allocation
1085 * parameters. The length units are all in realtime extents, as is the
1086 * result block number.
1087 */
1088 int /* error */
1089 xfs_rtallocate_extent(
1090 xfs_trans_t *tp, /* transaction pointer */
1091 xfs_rtblock_t bno, /* starting block number to allocate */
1092 xfs_extlen_t minlen, /* minimum length to allocate */
1093 xfs_extlen_t maxlen, /* maximum length to allocate */
1094 xfs_extlen_t *len, /* out: actual length allocated */
1095 xfs_alloctype_t type, /* allocation type XFS_ALLOCTYPE... */
1096 int wasdel, /* was a delayed allocation extent */
1097 xfs_extlen_t prod, /* extent product factor */
1098 xfs_rtblock_t *rtblock) /* out: start block allocated */
1099 {
1100 xfs_mount_t *mp = tp->t_mountp;
1101 int error; /* error value */
1102 xfs_rtblock_t r; /* result allocated block */
1103 xfs_fsblock_t sb; /* summary file block number */
1104 xfs_buf_t *sumbp; /* summary file block buffer */
1105
1106 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1107 ASSERT(minlen > 0 && minlen <= maxlen);
1108
1109 /*
1110 * If prod is set then figure out what to do to minlen and maxlen.
1111 */
1112 if (prod > 1) {
1113 xfs_extlen_t i;
1114
1115 if ((i = maxlen % prod))
1116 maxlen -= i;
1117 if ((i = minlen % prod))
1118 minlen += prod - i;
1119 if (maxlen < minlen) {
1120 *rtblock = NULLRTBLOCK;
1121 return 0;
1122 }
1123 }
1124
1125 sumbp = NULL;
1126 /*
1127 * Allocate by size, or near another block, or exactly at some block.
1128 */
1129 switch (type) {
1130 case XFS_ALLOCTYPE_ANY_AG:
1131 error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1132 &sumbp, &sb, prod, &r);
1133 break;
1134 case XFS_ALLOCTYPE_NEAR_BNO:
1135 error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1136 len, &sumbp, &sb, prod, &r);
1137 break;
1138 case XFS_ALLOCTYPE_THIS_BNO:
1139 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen,
1140 len, &sumbp, &sb, prod, &r);
1141 break;
1142 default:
1143 error = -EIO;
1144 ASSERT(0);
1145 }
1146 if (error)
1147 return error;
1148
1149 /*
1150 * If it worked, update the superblock.
1151 */
1152 if (r != NULLRTBLOCK) {
1153 long slen = (long)*len;
1154
1155 ASSERT(*len >= minlen && *len <= maxlen);
1156 if (wasdel)
1157 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1158 else
1159 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1160 }
1161 *rtblock = r;
1162 return 0;
1163 }
1164
1165 /*
1166 * Initialize realtime fields in the mount structure.
1167 */
1168 int /* error */
1169 xfs_rtmount_init(
1170 struct xfs_mount *mp) /* file system mount structure */
1171 {
1172 struct xfs_buf *bp; /* buffer for last block of subvolume */
1173 struct xfs_sb *sbp; /* filesystem superblock copy in mount */
1174 xfs_daddr_t d; /* address of last block of subvolume */
1175 int error;
1176
1177 sbp = &mp->m_sb;
1178 if (sbp->sb_rblocks == 0)
1179 return 0;
1180 if (mp->m_rtdev_targp == NULL) {
1181 xfs_warn(mp,
1182 "Filesystem has a realtime volume, use rtdev=device option");
1183 return -ENODEV;
1184 }
1185 mp->m_rsumlevels = sbp->sb_rextslog + 1;
1186 mp->m_rsumsize =
1187 (uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1188 sbp->sb_rbmblocks;
1189 mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1190 mp->m_rbmip = mp->m_rsumip = NULL;
1191 /*
1192 * Check that the realtime section is an ok size.
1193 */
1194 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1195 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1196 xfs_warn(mp, "realtime mount -- %llu != %llu",
1197 (unsigned long long) XFS_BB_TO_FSB(mp, d),
1198 (unsigned long long) mp->m_sb.sb_rblocks);
1199 return -EFBIG;
1200 }
1201 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1202 d - XFS_FSB_TO_BB(mp, 1),
1203 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1204 if (error) {
1205 xfs_warn(mp, "realtime device size check failed");
1206 return error;
1207 }
1208 xfs_buf_relse(bp);
1209 return 0;
1210 }
1211
1212 /*
1213 * Get the bitmap and summary inodes into the mount structure
1214 * at mount time.
1215 */
1216 int /* error */
1217 xfs_rtmount_inodes(
1218 xfs_mount_t *mp) /* file system mount structure */
1219 {
1220 int error; /* error return value */
1221 xfs_sb_t *sbp;
1222
1223 sbp = &mp->m_sb;
1224 if (sbp->sb_rbmino == NULLFSINO)
1225 return 0;
1226 error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1227 if (error)
1228 return error;
1229 ASSERT(mp->m_rbmip != NULL);
1230 ASSERT(sbp->sb_rsumino != NULLFSINO);
1231 error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1232 if (error) {
1233 IRELE(mp->m_rbmip);
1234 return error;
1235 }
1236 ASSERT(mp->m_rsumip != NULL);
1237 return 0;
1238 }
1239
1240 void
1241 xfs_rtunmount_inodes(
1242 struct xfs_mount *mp)
1243 {
1244 if (mp->m_rbmip)
1245 IRELE(mp->m_rbmip);
1246 if (mp->m_rsumip)
1247 IRELE(mp->m_rsumip);
1248 }
1249
1250 /*
1251 * Pick an extent for allocation at the start of a new realtime file.
1252 * Use the sequence number stored in the atime field of the bitmap inode.
1253 * Translate this to a fraction of the rtextents, and return the product
1254 * of rtextents and the fraction.
1255 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1256 */
1257 int /* error */
1258 xfs_rtpick_extent(
1259 xfs_mount_t *mp, /* file system mount point */
1260 xfs_trans_t *tp, /* transaction pointer */
1261 xfs_extlen_t len, /* allocation length (rtextents) */
1262 xfs_rtblock_t *pick) /* result rt extent */
1263 {
1264 xfs_rtblock_t b; /* result block */
1265 int log2; /* log of sequence number */
1266 __uint64_t resid; /* residual after log removed */
1267 __uint64_t seq; /* sequence number of file creation */
1268 __uint64_t *seqp; /* pointer to seqno in inode */
1269
1270 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1271
1272 seqp = (__uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1273 if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1274 mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1275 *seqp = 0;
1276 }
1277 seq = *seqp;
1278 if ((log2 = xfs_highbit64(seq)) == -1)
1279 b = 0;
1280 else {
1281 resid = seq - (1ULL << log2);
1282 b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1283 (log2 + 1);
1284 if (b >= mp->m_sb.sb_rextents)
1285 b = do_mod(b, mp->m_sb.sb_rextents);
1286 if (b + len > mp->m_sb.sb_rextents)
1287 b = mp->m_sb.sb_rextents - len;
1288 }
1289 *seqp = seq + 1;
1290 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1291 *pick = b;
1292 return 0;
1293 }
(deprecated) Btrfs devel tree