1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_shared.h"
9 #include "xfs_format.h"
10 #include "xfs_log_format.h"
11 #include "xfs_trans_resv.h"
12 #include "xfs_bit.h"
13 #include "xfs_mount.h"
14 #include "xfs_inode.h"
15 #include "xfs_bmap.h"
16 #include "xfs_bmap_btree.h"
17 #include "xfs_trans.h"
18 #include "xfs_trans_space.h"
19 #include "xfs_icache.h"
20 #include "xfs_rtalloc.h"
21
22
23 /*
24 * Read and return the summary information for a given extent size,
25 * bitmap block combination.
26 * Keeps track of a current summary block, so we don't keep reading
27 * it from the buffer cache.
28 */
29 static int
30 xfs_rtget_summary(
31 xfs_mount_t *mp, /* file system mount structure */
32 xfs_trans_t *tp, /* transaction pointer */
33 int log, /* log2 of extent size */
34 xfs_rtblock_t bbno, /* bitmap block number */
35 xfs_buf_t **rbpp, /* in/out: summary block buffer */
36 xfs_fsblock_t *rsb, /* in/out: summary block number */
37 xfs_suminfo_t *sum) /* out: summary info for this block */
38 {
39 return xfs_rtmodify_summary_int(mp, tp, log, bbno, 0, rbpp, rsb, sum);
40 }
41
42 /*
43 * Return whether there are any free extents in the size range given
44 * by low and high, for the bitmap block bbno.
45 */
46 STATIC int /* error */
47 xfs_rtany_summary(
48 xfs_mount_t *mp, /* file system mount structure */
49 xfs_trans_t *tp, /* transaction pointer */
50 int low, /* low log2 extent size */
51 int high, /* high log2 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 int *stat) /* out: any good extents here? */
56 {
57 int error; /* error value */
58 int log; /* loop counter, log2 of ext. size */
59 xfs_suminfo_t sum; /* summary data */
60
61 /* There are no extents at levels < m_rsum_cache[bbno]. */
62 if (mp->m_rsum_cache && low < mp->m_rsum_cache[bbno])
63 low = mp->m_rsum_cache[bbno];
64
65 /*
66 * Loop over logs of extent sizes.
67 */
68 for (log = low; log <= high; log++) {
69 /*
70 * Get one summary datum.
71 */
72 error = xfs_rtget_summary(mp, tp, log, bbno, rbpp, rsb, &sum);
73 if (error) {
74 return error;
75 }
76 /*
77 * If there are any, return success.
78 */
79 if (sum) {
80 *stat = 1;
81 goto out;
82 }
83 }
84 /*
85 * Found nothing, return failure.
86 */
87 *stat = 0;
88 out:
89 /* There were no extents at levels < log. */
90 if (mp->m_rsum_cache && log > mp->m_rsum_cache[bbno])
91 mp->m_rsum_cache[bbno] = log;
92 return 0;
93 }
94
95
96 /*
97 * Copy and transform the summary file, given the old and new
98 * parameters in the mount structures.
99 */
100 STATIC int /* error */
101 xfs_rtcopy_summary(
102 xfs_mount_t *omp, /* old file system mount point */
103 xfs_mount_t *nmp, /* new file system mount point */
104 xfs_trans_t *tp) /* transaction pointer */
105 {
106 xfs_rtblock_t bbno; /* bitmap block number */
107 xfs_buf_t *bp; /* summary buffer */
108 int error; /* error return value */
109 int log; /* summary level number (log length) */
110 xfs_suminfo_t sum; /* summary data */
111 xfs_fsblock_t sumbno; /* summary block number */
112
113 bp = NULL;
114 for (log = omp->m_rsumlevels - 1; log >= 0; log--) {
115 for (bbno = omp->m_sb.sb_rbmblocks - 1;
116 (xfs_srtblock_t)bbno >= 0;
117 bbno--) {
118 error = xfs_rtget_summary(omp, tp, log, bbno, &bp,
119 &sumbno, &sum);
120 if (error)
121 return error;
122 if (sum == 0)
123 continue;
124 error = xfs_rtmodify_summary(omp, tp, log, bbno, -sum,
125 &bp, &sumbno);
126 if (error)
127 return error;
128 error = xfs_rtmodify_summary(nmp, tp, log, bbno, sum,
129 &bp, &sumbno);
130 if (error)
131 return error;
132 ASSERT(sum > 0);
133 }
134 }
135 return 0;
136 }
137 /*
138 * Mark an extent specified by start and len allocated.
139 * Updates all the summary information as well as the bitmap.
140 */
141 STATIC int /* error */
142 xfs_rtallocate_range(
143 xfs_mount_t *mp, /* file system mount point */
144 xfs_trans_t *tp, /* transaction pointer */
145 xfs_rtblock_t start, /* start block to allocate */
146 xfs_extlen_t len, /* length to allocate */
147 xfs_buf_t **rbpp, /* in/out: summary block buffer */
148 xfs_fsblock_t *rsb) /* in/out: summary block number */
149 {
150 xfs_rtblock_t end; /* end of the allocated extent */
151 int error; /* error value */
152 xfs_rtblock_t postblock = 0; /* first block allocated > end */
153 xfs_rtblock_t preblock = 0; /* first block allocated < start */
154
155 end = start + len - 1;
156 /*
157 * Assume we're allocating out of the middle of a free extent.
158 * We need to find the beginning and end of the extent so we can
159 * properly update the summary.
160 */
161 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
162 if (error) {
163 return error;
164 }
165 /*
166 * Find the next allocated block (end of free extent).
167 */
168 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
169 &postblock);
170 if (error) {
171 return error;
172 }
173 /*
174 * Decrement the summary information corresponding to the entire
175 * (old) free extent.
176 */
177 error = xfs_rtmodify_summary(mp, tp,
178 XFS_RTBLOCKLOG(postblock + 1 - preblock),
179 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
180 if (error) {
181 return error;
182 }
183 /*
184 * If there are blocks not being allocated at the front of the
185 * old extent, add summary data for them to be free.
186 */
187 if (preblock < start) {
188 error = xfs_rtmodify_summary(mp, tp,
189 XFS_RTBLOCKLOG(start - preblock),
190 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
191 if (error) {
192 return error;
193 }
194 }
195 /*
196 * If there are blocks not being allocated at the end of the
197 * old extent, add summary data for them to be free.
198 */
199 if (postblock > end) {
200 error = xfs_rtmodify_summary(mp, tp,
201 XFS_RTBLOCKLOG(postblock - end),
202 XFS_BITTOBLOCK(mp, end + 1), 1, rbpp, rsb);
203 if (error) {
204 return error;
205 }
206 }
207 /*
208 * Modify the bitmap to mark this extent allocated.
209 */
210 error = xfs_rtmodify_range(mp, tp, start, len, 0);
211 return error;
212 }
213
214 /*
215 * Attempt to allocate an extent minlen<=len<=maxlen starting from
216 * bitmap block bbno. If we don't get maxlen then use prod to trim
217 * the length, if given. Returns error; returns starting block in *rtblock.
218 * The lengths are all in rtextents.
219 */
220 STATIC int /* error */
221 xfs_rtallocate_extent_block(
222 xfs_mount_t *mp, /* file system mount point */
223 xfs_trans_t *tp, /* transaction pointer */
224 xfs_rtblock_t bbno, /* bitmap block number */
225 xfs_extlen_t minlen, /* minimum length to allocate */
226 xfs_extlen_t maxlen, /* maximum length to allocate */
227 xfs_extlen_t *len, /* out: actual length allocated */
228 xfs_rtblock_t *nextp, /* out: next block to try */
229 xfs_buf_t **rbpp, /* in/out: summary block buffer */
230 xfs_fsblock_t *rsb, /* in/out: summary block number */
231 xfs_extlen_t prod, /* extent product factor */
232 xfs_rtblock_t *rtblock) /* out: start block allocated */
233 {
234 xfs_rtblock_t besti; /* best rtblock found so far */
235 xfs_rtblock_t bestlen; /* best length found so far */
236 xfs_rtblock_t end; /* last rtblock in chunk */
237 int error; /* error value */
238 xfs_rtblock_t i; /* current rtblock trying */
239 xfs_rtblock_t next; /* next rtblock to try */
240 int stat; /* status from internal calls */
241
242 /*
243 * Loop over all the extents starting in this bitmap block,
244 * looking for one that's long enough.
245 */
246 for (i = XFS_BLOCKTOBIT(mp, bbno), besti = -1, bestlen = 0,
247 end = XFS_BLOCKTOBIT(mp, bbno + 1) - 1;
248 i <= end;
249 i++) {
250 /*
251 * See if there's a free extent of maxlen starting at i.
252 * If it's not so then next will contain the first non-free.
253 */
254 error = xfs_rtcheck_range(mp, tp, i, maxlen, 1, &next, &stat);
255 if (error) {
256 return error;
257 }
258 if (stat) {
259 /*
260 * i for maxlen is all free, allocate and return that.
261 */
262 error = xfs_rtallocate_range(mp, tp, i, maxlen, rbpp,
263 rsb);
264 if (error) {
265 return error;
266 }
267 *len = maxlen;
268 *rtblock = i;
269 return 0;
270 }
271 /*
272 * In the case where we have a variable-sized allocation
273 * request, figure out how big this free piece is,
274 * and if it's big enough for the minimum, and the best
275 * so far, remember it.
276 */
277 if (minlen < maxlen) {
278 xfs_rtblock_t thislen; /* this extent size */
279
280 thislen = next - i;
281 if (thislen >= minlen && thislen > bestlen) {
282 besti = i;
283 bestlen = thislen;
284 }
285 }
286 /*
287 * If not done yet, find the start of the next free space.
288 */
289 if (next < end) {
290 error = xfs_rtfind_forw(mp, tp, next, end, &i);
291 if (error) {
292 return error;
293 }
294 } else
295 break;
296 }
297 /*
298 * Searched the whole thing & didn't find a maxlen free extent.
299 */
300 if (minlen < maxlen && besti != -1) {
301 xfs_extlen_t p; /* amount to trim length by */
302
303 /*
304 * If size should be a multiple of prod, make that so.
305 */
306 if (prod > 1) {
307 div_u64_rem(bestlen, prod, &p);
308 if (p)
309 bestlen -= p;
310 }
311
312 /*
313 * Allocate besti for bestlen & return that.
314 */
315 error = xfs_rtallocate_range(mp, tp, besti, bestlen, rbpp, rsb);
316 if (error) {
317 return error;
318 }
319 *len = bestlen;
320 *rtblock = besti;
321 return 0;
322 }
323 /*
324 * Allocation failed. Set *nextp to the next block to try.
325 */
326 *nextp = next;
327 *rtblock = NULLRTBLOCK;
328 return 0;
329 }
330
331 /*
332 * Allocate an extent of length minlen<=len<=maxlen, starting at block
333 * bno. If we don't get maxlen then use prod to trim the length, if given.
334 * Returns error; returns starting block in *rtblock.
335 * The lengths are all in rtextents.
336 */
337 STATIC int /* error */
338 xfs_rtallocate_extent_exact(
339 xfs_mount_t *mp, /* file system mount point */
340 xfs_trans_t *tp, /* transaction pointer */
341 xfs_rtblock_t bno, /* starting block number to allocate */
342 xfs_extlen_t minlen, /* minimum length to allocate */
343 xfs_extlen_t maxlen, /* maximum length to allocate */
344 xfs_extlen_t *len, /* out: actual length allocated */
345 xfs_buf_t **rbpp, /* in/out: summary block buffer */
346 xfs_fsblock_t *rsb, /* in/out: summary block number */
347 xfs_extlen_t prod, /* extent product factor */
348 xfs_rtblock_t *rtblock) /* out: start block allocated */
349 {
350 int error; /* error value */
351 xfs_extlen_t i; /* extent length trimmed due to prod */
352 int isfree; /* extent is free */
353 xfs_rtblock_t next; /* next block to try (dummy) */
354
355 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
356 /*
357 * Check if the range in question (for maxlen) is free.
358 */
359 error = xfs_rtcheck_range(mp, tp, bno, maxlen, 1, &next, &isfree);
360 if (error) {
361 return error;
362 }
363 if (isfree) {
364 /*
365 * If it is, allocate it and return success.
366 */
367 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
368 if (error) {
369 return error;
370 }
371 *len = maxlen;
372 *rtblock = bno;
373 return 0;
374 }
375 /*
376 * If not, allocate what there is, if it's at least minlen.
377 */
378 maxlen = next - bno;
379 if (maxlen < minlen) {
380 /*
381 * Failed, return failure status.
382 */
383 *rtblock = NULLRTBLOCK;
384 return 0;
385 }
386 /*
387 * Trim off tail of extent, if prod is specified.
388 */
389 if (prod > 1 && (i = maxlen % prod)) {
390 maxlen -= i;
391 if (maxlen < minlen) {
392 /*
393 * Now we can't do it, return failure status.
394 */
395 *rtblock = NULLRTBLOCK;
396 return 0;
397 }
398 }
399 /*
400 * Allocate what we can and return it.
401 */
402 error = xfs_rtallocate_range(mp, tp, bno, maxlen, rbpp, rsb);
403 if (error) {
404 return error;
405 }
406 *len = maxlen;
407 *rtblock = bno;
408 return 0;
409 }
410
411 /*
412 * Allocate an extent of length minlen<=len<=maxlen, starting as near
413 * to bno as possible. If we don't get maxlen then use prod to trim
414 * the length, if given. The lengths are all in rtextents.
415 */
416 STATIC int /* error */
417 xfs_rtallocate_extent_near(
418 xfs_mount_t *mp, /* file system mount point */
419 xfs_trans_t *tp, /* transaction pointer */
420 xfs_rtblock_t bno, /* starting block number to allocate */
421 xfs_extlen_t minlen, /* minimum length to allocate */
422 xfs_extlen_t maxlen, /* maximum length to allocate */
423 xfs_extlen_t *len, /* out: actual length allocated */
424 xfs_buf_t **rbpp, /* in/out: summary block buffer */
425 xfs_fsblock_t *rsb, /* in/out: summary block number */
426 xfs_extlen_t prod, /* extent product factor */
427 xfs_rtblock_t *rtblock) /* out: start block allocated */
428 {
429 int any; /* any useful extents from summary */
430 xfs_rtblock_t bbno; /* bitmap block number */
431 int error; /* error value */
432 int i; /* bitmap block offset (loop control) */
433 int j; /* secondary loop control */
434 int log2len; /* log2 of minlen */
435 xfs_rtblock_t n; /* next block to try */
436 xfs_rtblock_t r; /* result block */
437
438 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
439 /*
440 * If the block number given is off the end, silently set it to
441 * the last block.
442 */
443 if (bno >= mp->m_sb.sb_rextents)
444 bno = mp->m_sb.sb_rextents - 1;
445 /*
446 * Try the exact allocation first.
447 */
448 error = xfs_rtallocate_extent_exact(mp, tp, bno, minlen, maxlen, len,
449 rbpp, rsb, prod, &r);
450 if (error) {
451 return error;
452 }
453 /*
454 * If the exact allocation worked, return that.
455 */
456 if (r != NULLRTBLOCK) {
457 *rtblock = r;
458 return 0;
459 }
460 bbno = XFS_BITTOBLOCK(mp, bno);
461 i = 0;
462 ASSERT(minlen != 0);
463 log2len = xfs_highbit32(minlen);
464 /*
465 * Loop over all bitmap blocks (bbno + i is current block).
466 */
467 for (;;) {
468 /*
469 * Get summary information of extents of all useful levels
470 * starting in this bitmap block.
471 */
472 error = xfs_rtany_summary(mp, tp, log2len, mp->m_rsumlevels - 1,
473 bbno + i, rbpp, rsb, &any);
474 if (error) {
475 return error;
476 }
477 /*
478 * If there are any useful extents starting here, try
479 * allocating one.
480 */
481 if (any) {
482 /*
483 * On the positive side of the starting location.
484 */
485 if (i >= 0) {
486 /*
487 * Try to allocate an extent starting in
488 * this block.
489 */
490 error = xfs_rtallocate_extent_block(mp, tp,
491 bbno + i, minlen, maxlen, len, &n, rbpp,
492 rsb, prod, &r);
493 if (error) {
494 return error;
495 }
496 /*
497 * If it worked, return it.
498 */
499 if (r != NULLRTBLOCK) {
500 *rtblock = r;
501 return 0;
502 }
503 }
504 /*
505 * On the negative side of the starting location.
506 */
507 else { /* i < 0 */
508 /*
509 * Loop backwards through the bitmap blocks from
510 * the starting point-1 up to where we are now.
511 * There should be an extent which ends in this
512 * bitmap block and is long enough.
513 */
514 for (j = -1; j > i; j--) {
515 /*
516 * Grab the summary information for
517 * this bitmap block.
518 */
519 error = xfs_rtany_summary(mp, tp,
520 log2len, mp->m_rsumlevels - 1,
521 bbno + j, rbpp, rsb, &any);
522 if (error) {
523 return error;
524 }
525 /*
526 * If there's no extent given in the
527 * summary that means the extent we
528 * found must carry over from an
529 * earlier block. If there is an
530 * extent given, we've already tried
531 * that allocation, don't do it again.
532 */
533 if (any)
534 continue;
535 error = xfs_rtallocate_extent_block(mp,
536 tp, bbno + j, minlen, maxlen,
537 len, &n, rbpp, rsb, prod, &r);
538 if (error) {
539 return error;
540 }
541 /*
542 * If it works, return the extent.
543 */
544 if (r != NULLRTBLOCK) {
545 *rtblock = r;
546 return 0;
547 }
548 }
549 /*
550 * There weren't intervening bitmap blocks
551 * with a long enough extent, or the
552 * allocation didn't work for some reason
553 * (i.e. it's a little * too short).
554 * Try to allocate from the summary block
555 * that we found.
556 */
557 error = xfs_rtallocate_extent_block(mp, tp,
558 bbno + i, minlen, maxlen, len, &n, rbpp,
559 rsb, prod, &r);
560 if (error) {
561 return error;
562 }
563 /*
564 * If it works, return the extent.
565 */
566 if (r != NULLRTBLOCK) {
567 *rtblock = r;
568 return 0;
569 }
570 }
571 }
572 /*
573 * Loop control. If we were on the positive side, and there's
574 * still more blocks on the negative side, go there.
575 */
576 if (i > 0 && (int)bbno - i >= 0)
577 i = -i;
578 /*
579 * If positive, and no more negative, but there are more
580 * positive, go there.
581 */
582 else if (i > 0 && (int)bbno + i < mp->m_sb.sb_rbmblocks - 1)
583 i++;
584 /*
585 * If negative or 0 (just started), and there are positive
586 * blocks to go, go there. The 0 case moves to block 1.
587 */
588 else if (i <= 0 && (int)bbno - i < mp->m_sb.sb_rbmblocks - 1)
589 i = 1 - i;
590 /*
591 * If negative or 0 and there are more negative blocks,
592 * go there.
593 */
594 else if (i <= 0 && (int)bbno + i > 0)
595 i--;
596 /*
597 * Must be done. Return failure.
598 */
599 else
600 break;
601 }
602 *rtblock = NULLRTBLOCK;
603 return 0;
604 }
605
606 /*
607 * Allocate an extent of length minlen<=len<=maxlen, with no position
608 * specified. If we don't get maxlen then use prod to trim
609 * the length, if given. The lengths are all in rtextents.
610 */
611 STATIC int /* error */
612 xfs_rtallocate_extent_size(
613 xfs_mount_t *mp, /* file system mount point */
614 xfs_trans_t *tp, /* transaction pointer */
615 xfs_extlen_t minlen, /* minimum length to allocate */
616 xfs_extlen_t maxlen, /* maximum length to allocate */
617 xfs_extlen_t *len, /* out: actual length allocated */
618 xfs_buf_t **rbpp, /* in/out: summary block buffer */
619 xfs_fsblock_t *rsb, /* in/out: summary block number */
620 xfs_extlen_t prod, /* extent product factor */
621 xfs_rtblock_t *rtblock) /* out: start block allocated */
622 {
623 int error; /* error value */
624 int i; /* bitmap block number */
625 int l; /* level number (loop control) */
626 xfs_rtblock_t n; /* next block to be tried */
627 xfs_rtblock_t r; /* result block number */
628 xfs_suminfo_t sum; /* summary information for extents */
629
630 ASSERT(minlen % prod == 0 && maxlen % prod == 0);
631 ASSERT(maxlen != 0);
632
633 /*
634 * Loop over all the levels starting with maxlen.
635 * At each level, look at all the bitmap blocks, to see if there
636 * are extents starting there that are long enough (>= maxlen).
637 * Note, only on the initial level can the allocation fail if
638 * the summary says there's an extent.
639 */
640 for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
641 /*
642 * Loop over all the bitmap blocks.
643 */
644 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
645 /*
646 * Get the summary for this level/block.
647 */
648 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
649 &sum);
650 if (error) {
651 return error;
652 }
653 /*
654 * Nothing there, on to the next block.
655 */
656 if (!sum)
657 continue;
658 /*
659 * Try allocating the extent.
660 */
661 error = xfs_rtallocate_extent_block(mp, tp, i, maxlen,
662 maxlen, len, &n, rbpp, rsb, prod, &r);
663 if (error) {
664 return error;
665 }
666 /*
667 * If it worked, return that.
668 */
669 if (r != NULLRTBLOCK) {
670 *rtblock = r;
671 return 0;
672 }
673 /*
674 * If the "next block to try" returned from the
675 * allocator is beyond the next bitmap block,
676 * skip to that bitmap block.
677 */
678 if (XFS_BITTOBLOCK(mp, n) > i + 1)
679 i = XFS_BITTOBLOCK(mp, n) - 1;
680 }
681 }
682 /*
683 * Didn't find any maxlen blocks. Try smaller ones, unless
684 * we're asking for a fixed size extent.
685 */
686 if (minlen > --maxlen) {
687 *rtblock = NULLRTBLOCK;
688 return 0;
689 }
690 ASSERT(minlen != 0);
691 ASSERT(maxlen != 0);
692
693 /*
694 * Loop over sizes, from maxlen down to minlen.
695 * This time, when we do the allocations, allow smaller ones
696 * to succeed.
697 */
698 for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
699 /*
700 * Loop over all the bitmap blocks, try an allocation
701 * starting in that block.
702 */
703 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
704 /*
705 * Get the summary information for this level/block.
706 */
707 error = xfs_rtget_summary(mp, tp, l, i, rbpp, rsb,
708 &sum);
709 if (error) {
710 return error;
711 }
712 /*
713 * If nothing there, go on to next.
714 */
715 if (!sum)
716 continue;
717 /*
718 * Try the allocation. Make sure the specified
719 * minlen/maxlen are in the possible range for
720 * this summary level.
721 */
722 error = xfs_rtallocate_extent_block(mp, tp, i,
723 XFS_RTMAX(minlen, 1 << l),
724 XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
725 len, &n, rbpp, rsb, prod, &r);
726 if (error) {
727 return error;
728 }
729 /*
730 * If it worked, return that extent.
731 */
732 if (r != NULLRTBLOCK) {
733 *rtblock = r;
734 return 0;
735 }
736 /*
737 * If the "next block to try" returned from the
738 * allocator is beyond the next bitmap block,
739 * skip to that bitmap block.
740 */
741 if (XFS_BITTOBLOCK(mp, n) > i + 1)
742 i = XFS_BITTOBLOCK(mp, n) - 1;
743 }
744 }
745 /*
746 * Got nothing, return failure.
747 */
748 *rtblock = NULLRTBLOCK;
749 return 0;
750 }
751
752 /*
753 * Allocate space to the bitmap or summary file, and zero it, for growfs.
754 */
755 STATIC int
756 xfs_growfs_rt_alloc(
757 struct xfs_mount *mp, /* file system mount point */
758 xfs_extlen_t oblocks, /* old count of blocks */
759 xfs_extlen_t nblocks, /* new count of blocks */
760 struct xfs_inode *ip) /* inode (bitmap/summary) */
761 {
762 xfs_fileoff_t bno; /* block number in file */
763 struct xfs_buf *bp; /* temporary buffer for zeroing */
764 xfs_daddr_t d; /* disk block address */
765 int error; /* error return value */
766 xfs_fsblock_t fsbno; /* filesystem block for bno */
767 struct xfs_bmbt_irec map; /* block map output */
768 int nmap; /* number of block maps */
769 int resblks; /* space reservation */
770 struct xfs_trans *tp;
771
772 /*
773 * Allocate space to the file, as necessary.
774 */
775 while (oblocks < nblocks) {
776 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
777 /*
778 * Reserve space & log for one extent added to the file.
779 */
780 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtalloc, resblks,
781 0, 0, &tp);
782 if (error)
783 return error;
784 /*
785 * Lock the inode.
786 */
787 xfs_ilock(ip, XFS_ILOCK_EXCL);
788 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
789
790 /*
791 * Allocate blocks to the bitmap file.
792 */
793 nmap = 1;
794 error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
795 XFS_BMAPI_METADATA, resblks, &map,
796 &nmap);
797 if (!error && nmap < 1)
798 error = -ENOSPC;
799 if (error)
800 goto out_trans_cancel;
801 /*
802 * Free any blocks freed up in the transaction, then commit.
803 */
804 error = xfs_trans_commit(tp);
805 if (error)
806 return error;
807 /*
808 * Now we need to clear the allocated blocks.
809 * Do this one block per transaction, to keep it simple.
810 */
811 for (bno = map.br_startoff, fsbno = map.br_startblock;
812 bno < map.br_startoff + map.br_blockcount;
813 bno++, fsbno++) {
814 /*
815 * Reserve log for one block zeroing.
816 */
817 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
818 0, 0, 0, &tp);
819 if (error)
820 return error;
821 /*
822 * Lock the bitmap inode.
823 */
824 xfs_ilock(ip, XFS_ILOCK_EXCL);
825 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
826 /*
827 * Get a buffer for the block.
828 */
829 d = XFS_FSB_TO_DADDR(mp, fsbno);
830 bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
831 mp->m_bsize, 0);
832 if (bp == NULL) {
833 error = -EIO;
834 goto out_trans_cancel;
835 }
836 memset(bp->b_addr, 0, mp->m_sb.sb_blocksize);
837 xfs_trans_log_buf(tp, bp, 0, mp->m_sb.sb_blocksize - 1);
838 /*
839 * Commit the transaction.
840 */
841 error = xfs_trans_commit(tp);
842 if (error)
843 return error;
844 }
845 /*
846 * Go on to the next extent, if any.
847 */
848 oblocks = map.br_startoff + map.br_blockcount;
849 }
850
851 return 0;
852
853 out_trans_cancel:
854 xfs_trans_cancel(tp);
855 return error;
856 }
857
858 static void
859 xfs_alloc_rsum_cache(
860 xfs_mount_t *mp, /* file system mount structure */
861 xfs_extlen_t rbmblocks) /* number of rt bitmap blocks */
862 {
863 /*
864 * The rsum cache is initialized to all zeroes, which is trivially a
865 * lower bound on the minimum level with any free extents. We can
866 * continue without the cache if it couldn't be allocated.
867 */
868 mp->m_rsum_cache = kmem_zalloc_large(rbmblocks, 0);
869 if (!mp->m_rsum_cache)
870 xfs_warn(mp, "could not allocate realtime summary cache");
871 }
872
873 /*
874 * Visible (exported) functions.
875 */
876
877 /*
878 * Grow the realtime area of the filesystem.
879 */
880 int
881 xfs_growfs_rt(
882 xfs_mount_t *mp, /* mount point for filesystem */
883 xfs_growfs_rt_t *in) /* growfs rt input struct */
884 {
885 xfs_rtblock_t bmbno; /* bitmap block number */
886 xfs_buf_t *bp; /* temporary buffer */
887 int error; /* error return value */
888 xfs_mount_t *nmp; /* new (fake) mount structure */
889 xfs_rfsblock_t nrblocks; /* new number of realtime blocks */
890 xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
891 xfs_rtblock_t nrextents; /* new number of realtime extents */
892 uint8_t nrextslog; /* new log2 of sb_rextents */
893 xfs_extlen_t nrsumblocks; /* new number of summary blocks */
894 uint nrsumlevels; /* new rt summary levels */
895 uint nrsumsize; /* new size of rt summary, bytes */
896 xfs_sb_t *nsbp; /* new superblock */
897 xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
898 xfs_extlen_t rsumblocks; /* current number of rt summary blks */
899 xfs_sb_t *sbp; /* old superblock */
900 xfs_fsblock_t sumbno; /* summary block number */
901 uint8_t *rsum_cache; /* old summary cache */
902
903 sbp = &mp->m_sb;
904 /*
905 * Initial error checking.
906 */
907 if (!capable(CAP_SYS_ADMIN))
908 return -EPERM;
909 if (mp->m_rtdev_targp == NULL || mp->m_rbmip == NULL ||
910 (nrblocks = in->newblocks) <= sbp->sb_rblocks ||
911 (sbp->sb_rblocks && (in->extsize != sbp->sb_rextsize)))
912 return -EINVAL;
913 if ((error = xfs_sb_validate_fsb_count(sbp, nrblocks)))
914 return error;
915 /*
916 * Read in the last block of the device, make sure it exists.
917 */
918 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
919 XFS_FSB_TO_BB(mp, nrblocks - 1),
920 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
921 if (error)
922 return error;
923 xfs_buf_relse(bp);
924
925 /*
926 * Calculate new parameters. These are the final values to be reached.
927 */
928 nrextents = nrblocks;
929 do_div(nrextents, in->extsize);
930 nrbmblocks = howmany_64(nrextents, NBBY * sbp->sb_blocksize);
931 nrextslog = xfs_highbit32(nrextents);
932 nrsumlevels = nrextslog + 1;
933 nrsumsize = (uint)sizeof(xfs_suminfo_t) * nrsumlevels * nrbmblocks;
934 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
935 nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
936 /*
937 * New summary size can't be more than half the size of
938 * the log. This prevents us from getting a log overflow,
939 * since we'll log basically the whole summary file at once.
940 */
941 if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
942 return -EINVAL;
943 /*
944 * Get the old block counts for bitmap and summary inodes.
945 * These can't change since other growfs callers are locked out.
946 */
947 rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_d.di_size);
948 rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_d.di_size);
949 /*
950 * Allocate space to the bitmap and summary files, as necessary.
951 */
952 error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
953 if (error)
954 return error;
955 error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
956 if (error)
957 return error;
958
959 rsum_cache = mp->m_rsum_cache;
960 if (nrbmblocks != sbp->sb_rbmblocks)
961 xfs_alloc_rsum_cache(mp, nrbmblocks);
962
963 /*
964 * Allocate a new (fake) mount/sb.
965 */
966 nmp = kmem_alloc(sizeof(*nmp), 0);
967 /*
968 * Loop over the bitmap blocks.
969 * We will do everything one bitmap block at a time.
970 * Skip the current block if it is exactly full.
971 * This also deals with the case where there were no rtextents before.
972 */
973 for (bmbno = sbp->sb_rbmblocks -
974 ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
975 bmbno < nrbmblocks;
976 bmbno++) {
977 xfs_trans_t *tp;
978
979 *nmp = *mp;
980 nsbp = &nmp->m_sb;
981 /*
982 * Calculate new sb and mount fields for this round.
983 */
984 nsbp->sb_rextsize = in->extsize;
985 nsbp->sb_rbmblocks = bmbno + 1;
986 nsbp->sb_rblocks =
987 XFS_RTMIN(nrblocks,
988 nsbp->sb_rbmblocks * NBBY *
989 nsbp->sb_blocksize * nsbp->sb_rextsize);
990 nsbp->sb_rextents = nsbp->sb_rblocks;
991 do_div(nsbp->sb_rextents, nsbp->sb_rextsize);
992 ASSERT(nsbp->sb_rextents != 0);
993 nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
994 nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
995 nrsumsize =
996 (uint)sizeof(xfs_suminfo_t) * nrsumlevels *
997 nsbp->sb_rbmblocks;
998 nrsumblocks = XFS_B_TO_FSB(mp, nrsumsize);
999 nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1000 /*
1001 * Start a transaction, get the log reservation.
1002 */
1003 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
1004 &tp);
1005 if (error)
1006 break;
1007 /*
1008 * Lock out other callers by grabbing the bitmap inode lock.
1009 */
1010 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL);
1011 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1012 /*
1013 * Update the bitmap inode's size.
1014 */
1015 mp->m_rbmip->i_d.di_size =
1016 nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1017 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1018 /*
1019 * Get the summary inode into the transaction.
1020 */
1021 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL);
1022 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1023 /*
1024 * Update the summary inode's size.
1025 */
1026 mp->m_rsumip->i_d.di_size = nmp->m_rsumsize;
1027 xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1028 /*
1029 * Copy summary data from old to new sizes.
1030 * Do this when the real size (not block-aligned) changes.
1031 */
1032 if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1033 mp->m_rsumlevels != nmp->m_rsumlevels) {
1034 error = xfs_rtcopy_summary(mp, nmp, tp);
1035 if (error)
1036 goto error_cancel;
1037 }
1038 /*
1039 * Update superblock fields.
1040 */
1041 if (nsbp->sb_rextsize != sbp->sb_rextsize)
1042 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1043 nsbp->sb_rextsize - sbp->sb_rextsize);
1044 if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1045 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1046 nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1047 if (nsbp->sb_rblocks != sbp->sb_rblocks)
1048 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1049 nsbp->sb_rblocks - sbp->sb_rblocks);
1050 if (nsbp->sb_rextents != sbp->sb_rextents)
1051 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1052 nsbp->sb_rextents - sbp->sb_rextents);
1053 if (nsbp->sb_rextslog != sbp->sb_rextslog)
1054 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1055 nsbp->sb_rextslog - sbp->sb_rextslog);
1056 /*
1057 * Free new extent.
1058 */
1059 bp = NULL;
1060 error = xfs_rtfree_range(nmp, tp, sbp->sb_rextents,
1061 nsbp->sb_rextents - sbp->sb_rextents, &bp, &sumbno);
1062 if (error) {
1063 error_cancel:
1064 xfs_trans_cancel(tp);
1065 break;
1066 }
1067 /*
1068 * Mark more blocks free in the superblock.
1069 */
1070 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1071 nsbp->sb_rextents - sbp->sb_rextents);
1072 /*
1073 * Update mp values into the real mp structure.
1074 */
1075 mp->m_rsumlevels = nrsumlevels;
1076 mp->m_rsumsize = nrsumsize;
1077
1078 error = xfs_trans_commit(tp);
1079 if (error)
1080 break;
1081 }
1082
1083 /*
1084 * Free the fake mp structure.
1085 */
1086 kmem_free(nmp);
1087
1088 /*
1089 * If we had to allocate a new rsum_cache, we either need to free the
1090 * old one (if we succeeded) or free the new one and restore the old one
1091 * (if there was an error).
1092 */
1093 if (rsum_cache != mp->m_rsum_cache) {
1094 if (error) {
1095 kmem_free(mp->m_rsum_cache);
1096 mp->m_rsum_cache = rsum_cache;
1097 } else {
1098 kmem_free(rsum_cache);
1099 }
1100 }
1101
1102 return error;
1103 }
1104
1105 /*
1106 * Allocate an extent in the realtime subvolume, with the usual allocation
1107 * parameters. The length units are all in realtime extents, as is the
1108 * result block number.
1109 */
1110 int /* error */
1111 xfs_rtallocate_extent(
1112 xfs_trans_t *tp, /* transaction pointer */
1113 xfs_rtblock_t bno, /* starting block number to allocate */
1114 xfs_extlen_t minlen, /* minimum length to allocate */
1115 xfs_extlen_t maxlen, /* maximum length to allocate */
1116 xfs_extlen_t *len, /* out: actual length allocated */
1117 int wasdel, /* was a delayed allocation extent */
1118 xfs_extlen_t prod, /* extent product factor */
1119 xfs_rtblock_t *rtblock) /* out: start block allocated */
1120 {
1121 xfs_mount_t *mp = tp->t_mountp;
1122 int error; /* error value */
1123 xfs_rtblock_t r; /* result allocated block */
1124 xfs_fsblock_t sb; /* summary file block number */
1125 xfs_buf_t *sumbp; /* summary file block buffer */
1126
1127 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1128 ASSERT(minlen > 0 && minlen <= maxlen);
1129
1130 /*
1131 * If prod is set then figure out what to do to minlen and maxlen.
1132 */
1133 if (prod > 1) {
1134 xfs_extlen_t i;
1135
1136 if ((i = maxlen % prod))
1137 maxlen -= i;
1138 if ((i = minlen % prod))
1139 minlen += prod - i;
1140 if (maxlen < minlen) {
1141 *rtblock = NULLRTBLOCK;
1142 return 0;
1143 }
1144 }
1145
1146 retry:
1147 sumbp = NULL;
1148 if (bno == 0) {
1149 error = xfs_rtallocate_extent_size(mp, tp, minlen, maxlen, len,
1150 &sumbp, &sb, prod, &r);
1151 } else {
1152 error = xfs_rtallocate_extent_near(mp, tp, bno, minlen, maxlen,
1153 len, &sumbp, &sb, prod, &r);
1154 }
1155
1156 if (error)
1157 return error;
1158
1159 /*
1160 * If it worked, update the superblock.
1161 */
1162 if (r != NULLRTBLOCK) {
1163 long slen = (long)*len;
1164
1165 ASSERT(*len >= minlen && *len <= maxlen);
1166 if (wasdel)
1167 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1168 else
1169 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1170 } else if (prod > 1) {
1171 prod = 1;
1172 goto retry;
1173 }
1174
1175 *rtblock = r;
1176 return 0;
1177 }
1178
1179 /*
1180 * Initialize realtime fields in the mount structure.
1181 */
1182 int /* error */
1183 xfs_rtmount_init(
1184 struct xfs_mount *mp) /* file system mount structure */
1185 {
1186 struct xfs_buf *bp; /* buffer for last block of subvolume */
1187 struct xfs_sb *sbp; /* filesystem superblock copy in mount */
1188 xfs_daddr_t d; /* address of last block of subvolume */
1189 int error;
1190
1191 sbp = &mp->m_sb;
1192 if (sbp->sb_rblocks == 0)
1193 return 0;
1194 if (mp->m_rtdev_targp == NULL) {
1195 xfs_warn(mp,
1196 "Filesystem has a realtime volume, use rtdev=device option");
1197 return -ENODEV;
1198 }
1199 mp->m_rsumlevels = sbp->sb_rextslog + 1;
1200 mp->m_rsumsize =
1201 (uint)sizeof(xfs_suminfo_t) * mp->m_rsumlevels *
1202 sbp->sb_rbmblocks;
1203 mp->m_rsumsize = roundup(mp->m_rsumsize, sbp->sb_blocksize);
1204 mp->m_rbmip = mp->m_rsumip = NULL;
1205 /*
1206 * Check that the realtime section is an ok size.
1207 */
1208 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1209 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1210 xfs_warn(mp, "realtime mount -- %llu != %llu",
1211 (unsigned long long) XFS_BB_TO_FSB(mp, d),
1212 (unsigned long long) mp->m_sb.sb_rblocks);
1213 return -EFBIG;
1214 }
1215 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
1216 d - XFS_FSB_TO_BB(mp, 1),
1217 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
1218 if (error) {
1219 xfs_warn(mp, "realtime device size check failed");
1220 return error;
1221 }
1222 xfs_buf_relse(bp);
1223 return 0;
1224 }
1225
1226 /*
1227 * Get the bitmap and summary inodes and the summary cache into the mount
1228 * structure at mount time.
1229 */
1230 int /* error */
1231 xfs_rtmount_inodes(
1232 xfs_mount_t *mp) /* file system mount structure */
1233 {
1234 int error; /* error return value */
1235 xfs_sb_t *sbp;
1236
1237 sbp = &mp->m_sb;
1238 error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1239 if (error)
1240 return error;
1241 ASSERT(mp->m_rbmip != NULL);
1242
1243 error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1244 if (error) {
1245 xfs_irele(mp->m_rbmip);
1246 return error;
1247 }
1248 ASSERT(mp->m_rsumip != NULL);
1249 xfs_alloc_rsum_cache(mp, sbp->sb_rbmblocks);
1250 return 0;
1251 }
1252
1253 void
1254 xfs_rtunmount_inodes(
1255 struct xfs_mount *mp)
1256 {
1257 kmem_free(mp->m_rsum_cache);
1258 if (mp->m_rbmip)
1259 xfs_irele(mp->m_rbmip);
1260 if (mp->m_rsumip)
1261 xfs_irele(mp->m_rsumip);
1262 }
1263
1264 /*
1265 * Pick an extent for allocation at the start of a new realtime file.
1266 * Use the sequence number stored in the atime field of the bitmap inode.
1267 * Translate this to a fraction of the rtextents, and return the product
1268 * of rtextents and the fraction.
1269 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1270 */
1271 int /* error */
1272 xfs_rtpick_extent(
1273 xfs_mount_t *mp, /* file system mount point */
1274 xfs_trans_t *tp, /* transaction pointer */
1275 xfs_extlen_t len, /* allocation length (rtextents) */
1276 xfs_rtblock_t *pick) /* result rt extent */
1277 {
1278 xfs_rtblock_t b; /* result block */
1279 int log2; /* log of sequence number */
1280 uint64_t resid; /* residual after log removed */
1281 uint64_t seq; /* sequence number of file creation */
1282 uint64_t *seqp; /* pointer to seqno in inode */
1283
1284 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1285
1286 seqp = (uint64_t *)&VFS_I(mp->m_rbmip)->i_atime;
1287 if (!(mp->m_rbmip->i_d.di_flags & XFS_DIFLAG_NEWRTBM)) {
1288 mp->m_rbmip->i_d.di_flags |= XFS_DIFLAG_NEWRTBM;
1289 *seqp = 0;
1290 }
1291 seq = *seqp;
1292 if ((log2 = xfs_highbit64(seq)) == -1)
1293 b = 0;
1294 else {
1295 resid = seq - (1ULL << log2);
1296 b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1297 (log2 + 1);
1298 if (b >= mp->m_sb.sb_rextents)
1299 div64_u64_rem(b, mp->m_sb.sb_rextents, &b);
1300 if (b + len > mp->m_sb.sb_rextents)
1301 b = mp->m_sb.sb_rextents - len;
1302 }
1303 *seqp = seq + 1;
1304 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1305 *pick = b;
1306 return 0;
1307 }