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#include "xfs_sb.h"
22#include "xfs_rtbitmap.h"
23
24/*
25 * Read and return the summary information for a given extent size,
26 * bitmap block combination.
27 * Keeps track of a current summary block, so we don't keep reading
28 * it from the buffer cache.
29 */
30static int
31xfs_rtget_summary(
32 struct xfs_rtalloc_args *args,
33 int log, /* log2 of extent size */
34 xfs_fileoff_t bbno, /* bitmap block number */
35 xfs_suminfo_t *sum) /* out: summary info for this block */
36{
37 return xfs_rtmodify_summary_int(args, log, bbno, 0, sum);
38}
39
40/*
41 * Return whether there are any free extents in the size range given
42 * by low and high, for the bitmap block bbno.
43 */
44STATIC int
45xfs_rtany_summary(
46 struct xfs_rtalloc_args *args,
47 int low, /* low log2 extent size */
48 int high, /* high log2 extent size */
49 xfs_fileoff_t bbno, /* bitmap block number */
50 int *maxlog) /* out: max log2 extent size free */
51{
52 struct xfs_mount *mp = args->mp;
53 int error;
54 int log; /* loop counter, log2 of ext. size */
55 xfs_suminfo_t sum; /* summary data */
56
57 /* There are no extents at levels >= m_rsum_cache[bbno]. */
58 if (mp->m_rsum_cache) {
59 high = min(high, mp->m_rsum_cache[bbno] - 1);
60 if (low > high) {
61 *maxlog = -1;
62 return 0;
63 }
64 }
65
66 /*
67 * Loop over logs of extent sizes.
68 */
69 for (log = high; log >= low; log--) {
70 /*
71 * Get one summary datum.
72 */
73 error = xfs_rtget_summary(args, log, bbno, &sum);
74 if (error) {
75 return error;
76 }
77 /*
78 * If there are any, return success.
79 */
80 if (sum) {
81 *maxlog = log;
82 goto out;
83 }
84 }
85 /*
86 * Found nothing, return failure.
87 */
88 *maxlog = -1;
89out:
90 /* There were no extents at levels > log. */
91 if (mp->m_rsum_cache && log + 1 < mp->m_rsum_cache[bbno])
92 mp->m_rsum_cache[bbno] = log + 1;
93 return 0;
94}
95
96
97/*
98 * Copy and transform the summary file, given the old and new
99 * parameters in the mount structures.
100 */
101STATIC int
102xfs_rtcopy_summary(
103 struct xfs_rtalloc_args *oargs,
104 struct xfs_rtalloc_args *nargs)
105{
106 xfs_fileoff_t bbno; /* bitmap block number */
107 int error;
108 int log; /* summary level number (log length) */
109 xfs_suminfo_t sum; /* summary data */
110
111 for (log = oargs->mp->m_rsumlevels - 1; log >= 0; log--) {
112 for (bbno = oargs->mp->m_sb.sb_rbmblocks - 1;
113 (xfs_srtblock_t)bbno >= 0;
114 bbno--) {
115 error = xfs_rtget_summary(oargs, log, bbno, &sum);
116 if (error)
117 goto out;
118 if (sum == 0)
119 continue;
120 error = xfs_rtmodify_summary(oargs, log, bbno, -sum);
121 if (error)
122 goto out;
123 error = xfs_rtmodify_summary(nargs, log, bbno, sum);
124 if (error)
125 goto out;
126 ASSERT(sum > 0);
127 }
128 }
129 error = 0;
130out:
131 xfs_rtbuf_cache_relse(oargs);
132 return 0;
133}
134/*
135 * Mark an extent specified by start and len allocated.
136 * Updates all the summary information as well as the bitmap.
137 */
138STATIC int
139xfs_rtallocate_range(
140 struct xfs_rtalloc_args *args,
141 xfs_rtxnum_t start, /* start rtext to allocate */
142 xfs_rtxlen_t len) /* in/out: summary block number */
143{
144 struct xfs_mount *mp = args->mp;
145 xfs_rtxnum_t end; /* end of the allocated rtext */
146 int error;
147 xfs_rtxnum_t postblock = 0; /* first rtext allocated > end */
148 xfs_rtxnum_t preblock = 0; /* first rtext allocated < start */
149
150 end = start + len - 1;
151 /*
152 * Assume we're allocating out of the middle of a free extent.
153 * We need to find the beginning and end of the extent so we can
154 * properly update the summary.
155 */
156 error = xfs_rtfind_back(args, start, 0, &preblock);
157 if (error) {
158 return error;
159 }
160 /*
161 * Find the next allocated block (end of free extent).
162 */
163 error = xfs_rtfind_forw(args, end, mp->m_sb.sb_rextents - 1,
164 &postblock);
165 if (error) {
166 return error;
167 }
168 /*
169 * Decrement the summary information corresponding to the entire
170 * (old) free extent.
171 */
172 error = xfs_rtmodify_summary(args,
173 XFS_RTBLOCKLOG(postblock + 1 - preblock),
174 xfs_rtx_to_rbmblock(mp, preblock), -1);
175 if (error) {
176 return error;
177 }
178 /*
179 * If there are blocks not being allocated at the front of the
180 * old extent, add summary data for them to be free.
181 */
182 if (preblock < start) {
183 error = xfs_rtmodify_summary(args,
184 XFS_RTBLOCKLOG(start - preblock),
185 xfs_rtx_to_rbmblock(mp, preblock), 1);
186 if (error) {
187 return error;
188 }
189 }
190 /*
191 * If there are blocks not being allocated at the end of the
192 * old extent, add summary data for them to be free.
193 */
194 if (postblock > end) {
195 error = xfs_rtmodify_summary(args,
196 XFS_RTBLOCKLOG(postblock - end),
197 xfs_rtx_to_rbmblock(mp, end + 1), 1);
198 if (error) {
199 return error;
200 }
201 }
202 /*
203 * Modify the bitmap to mark this extent allocated.
204 */
205 error = xfs_rtmodify_range(args, start, len, 0);
206 return error;
207}
208
209/*
210 * Make sure we don't run off the end of the rt volume. Be careful that
211 * adjusting maxlen downwards doesn't cause us to fail the alignment checks.
212 */
213static inline xfs_rtxlen_t
214xfs_rtallocate_clamp_len(
215 struct xfs_mount *mp,
216 xfs_rtxnum_t startrtx,
217 xfs_rtxlen_t rtxlen,
218 xfs_rtxlen_t prod)
219{
220 xfs_rtxlen_t ret;
221
222 ret = min(mp->m_sb.sb_rextents, startrtx + rtxlen) - startrtx;
223 return rounddown(ret, prod);
224}
225
226/*
227 * Attempt to allocate an extent minlen<=len<=maxlen starting from
228 * bitmap block bbno. If we don't get maxlen then use prod to trim
229 * the length, if given. Returns error; returns starting block in *rtx.
230 * The lengths are all in rtextents.
231 */
232STATIC int
233xfs_rtallocate_extent_block(
234 struct xfs_rtalloc_args *args,
235 xfs_fileoff_t bbno, /* bitmap block number */
236 xfs_rtxlen_t minlen, /* minimum length to allocate */
237 xfs_rtxlen_t maxlen, /* maximum length to allocate */
238 xfs_rtxlen_t *len, /* out: actual length allocated */
239 xfs_rtxnum_t *nextp, /* out: next rtext to try */
240 xfs_rtxlen_t prod, /* extent product factor */
241 xfs_rtxnum_t *rtx) /* out: start rtext allocated */
242{
243 struct xfs_mount *mp = args->mp;
244 xfs_rtxnum_t besti; /* best rtext found so far */
245 xfs_rtxnum_t bestlen;/* best length found so far */
246 xfs_rtxnum_t end; /* last rtext in chunk */
247 int error;
248 xfs_rtxnum_t i; /* current rtext trying */
249 xfs_rtxnum_t next; /* next rtext to try */
250 int stat; /* status from internal calls */
251
252 /*
253 * Loop over all the extents starting in this bitmap block,
254 * looking for one that's long enough.
255 */
256 for (i = xfs_rbmblock_to_rtx(mp, bbno), besti = -1, bestlen = 0,
257 end = xfs_rbmblock_to_rtx(mp, bbno + 1) - 1;
258 i <= end;
259 i++) {
260 /* Make sure we don't scan off the end of the rt volume. */
261 maxlen = xfs_rtallocate_clamp_len(mp, i, maxlen, prod);
262
263 /*
264 * See if there's a free extent of maxlen starting at i.
265 * If it's not so then next will contain the first non-free.
266 */
267 error = xfs_rtcheck_range(args, i, maxlen, 1, &next, &stat);
268 if (error) {
269 return error;
270 }
271 if (stat) {
272 /*
273 * i for maxlen is all free, allocate and return that.
274 */
275 error = xfs_rtallocate_range(args, i, maxlen);
276 if (error) {
277 return error;
278 }
279 *len = maxlen;
280 *rtx = i;
281 return 0;
282 }
283 /*
284 * In the case where we have a variable-sized allocation
285 * request, figure out how big this free piece is,
286 * and if it's big enough for the minimum, and the best
287 * so far, remember it.
288 */
289 if (minlen < maxlen) {
290 xfs_rtxnum_t thislen; /* this extent size */
291
292 thislen = next - i;
293 if (thislen >= minlen && thislen > bestlen) {
294 besti = i;
295 bestlen = thislen;
296 }
297 }
298 /*
299 * If not done yet, find the start of the next free space.
300 */
301 if (next < end) {
302 error = xfs_rtfind_forw(args, next, end, &i);
303 if (error) {
304 return error;
305 }
306 } else
307 break;
308 }
309 /*
310 * Searched the whole thing & didn't find a maxlen free extent.
311 */
312 if (minlen < maxlen && besti != -1) {
313 xfs_rtxlen_t p; /* amount to trim length by */
314
315 /*
316 * If size should be a multiple of prod, make that so.
317 */
318 if (prod > 1) {
319 div_u64_rem(bestlen, prod, &p);
320 if (p)
321 bestlen -= p;
322 }
323
324 /*
325 * Allocate besti for bestlen & return that.
326 */
327 error = xfs_rtallocate_range(args, besti, bestlen);
328 if (error) {
329 return error;
330 }
331 *len = bestlen;
332 *rtx = besti;
333 return 0;
334 }
335 /*
336 * Allocation failed. Set *nextp to the next block to try.
337 */
338 *nextp = next;
339 *rtx = NULLRTEXTNO;
340 return 0;
341}
342
343/*
344 * Allocate an extent of length minlen<=len<=maxlen, starting at block
345 * bno. If we don't get maxlen then use prod to trim the length, if given.
346 * Returns error; returns starting block in *rtx.
347 * The lengths are all in rtextents.
348 */
349STATIC int
350xfs_rtallocate_extent_exact(
351 struct xfs_rtalloc_args *args,
352 xfs_rtxnum_t start, /* starting rtext number to allocate */
353 xfs_rtxlen_t minlen, /* minimum length to allocate */
354 xfs_rtxlen_t maxlen, /* maximum length to allocate */
355 xfs_rtxlen_t *len, /* out: actual length allocated */
356 xfs_rtxlen_t prod, /* extent product factor */
357 xfs_rtxnum_t *rtx) /* out: start rtext allocated */
358{
359 int error;
360 xfs_rtxlen_t i; /* extent length trimmed due to prod */
361 int isfree; /* extent is free */
362 xfs_rtxnum_t next; /* next rtext to try (dummy) */
363
364 ASSERT(minlen % prod == 0);
365 ASSERT(maxlen % prod == 0);
366 /*
367 * Check if the range in question (for maxlen) is free.
368 */
369 error = xfs_rtcheck_range(args, start, maxlen, 1, &next, &isfree);
370 if (error) {
371 return error;
372 }
373 if (isfree) {
374 /*
375 * If it is, allocate it and return success.
376 */
377 error = xfs_rtallocate_range(args, start, maxlen);
378 if (error) {
379 return error;
380 }
381 *len = maxlen;
382 *rtx = start;
383 return 0;
384 }
385 /*
386 * If not, allocate what there is, if it's at least minlen.
387 */
388 maxlen = next - start;
389 if (maxlen < minlen) {
390 /*
391 * Failed, return failure status.
392 */
393 *rtx = NULLRTEXTNO;
394 return 0;
395 }
396 /*
397 * Trim off tail of extent, if prod is specified.
398 */
399 if (prod > 1 && (i = maxlen % prod)) {
400 maxlen -= i;
401 if (maxlen < minlen) {
402 /*
403 * Now we can't do it, return failure status.
404 */
405 *rtx = NULLRTEXTNO;
406 return 0;
407 }
408 }
409 /*
410 * Allocate what we can and return it.
411 */
412 error = xfs_rtallocate_range(args, start, maxlen);
413 if (error) {
414 return error;
415 }
416 *len = maxlen;
417 *rtx = start;
418 return 0;
419}
420
421/*
422 * Allocate an extent of length minlen<=len<=maxlen, starting as near
423 * to start as possible. If we don't get maxlen then use prod to trim
424 * the length, if given. The lengths are all in rtextents.
425 */
426STATIC int
427xfs_rtallocate_extent_near(
428 struct xfs_rtalloc_args *args,
429 xfs_rtxnum_t start, /* starting rtext number to allocate */
430 xfs_rtxlen_t minlen, /* minimum length to allocate */
431 xfs_rtxlen_t maxlen, /* maximum length to allocate */
432 xfs_rtxlen_t *len, /* out: actual length allocated */
433 xfs_rtxlen_t prod, /* extent product factor */
434 xfs_rtxnum_t *rtx) /* out: start rtext allocated */
435{
436 struct xfs_mount *mp = args->mp;
437 int maxlog; /* max useful extent from summary */
438 xfs_fileoff_t bbno; /* bitmap block number */
439 int error;
440 int i; /* bitmap block offset (loop control) */
441 int j; /* secondary loop control */
442 int log2len; /* log2 of minlen */
443 xfs_rtxnum_t n; /* next rtext to try */
444 xfs_rtxnum_t r; /* result rtext */
445
446 ASSERT(minlen % prod == 0);
447 ASSERT(maxlen % prod == 0);
448
449 /*
450 * If the block number given is off the end, silently set it to
451 * the last block.
452 */
453 if (start >= mp->m_sb.sb_rextents)
454 start = mp->m_sb.sb_rextents - 1;
455
456 /* Make sure we don't run off the end of the rt volume. */
457 maxlen = xfs_rtallocate_clamp_len(mp, start, maxlen, prod);
458 if (maxlen < minlen) {
459 *rtx = NULLRTEXTNO;
460 return 0;
461 }
462
463 /*
464 * Try the exact allocation first.
465 */
466 error = xfs_rtallocate_extent_exact(args, start, minlen, maxlen, len,
467 prod, &r);
468 if (error) {
469 return error;
470 }
471 /*
472 * If the exact allocation worked, return that.
473 */
474 if (r != NULLRTEXTNO) {
475 *rtx = r;
476 return 0;
477 }
478 bbno = xfs_rtx_to_rbmblock(mp, start);
479 i = 0;
480 j = -1;
481 ASSERT(minlen != 0);
482 log2len = xfs_highbit32(minlen);
483 /*
484 * Loop over all bitmap blocks (bbno + i is current block).
485 */
486 for (;;) {
487 /*
488 * Get summary information of extents of all useful levels
489 * starting in this bitmap block.
490 */
491 error = xfs_rtany_summary(args, log2len, mp->m_rsumlevels - 1,
492 bbno + i, &maxlog);
493 if (error) {
494 return error;
495 }
496 /*
497 * If there are any useful extents starting here, try
498 * allocating one.
499 */
500 if (maxlog >= 0) {
501 xfs_extlen_t maxavail =
502 min_t(xfs_rtblock_t, maxlen,
503 (1ULL << (maxlog + 1)) - 1);
504 /*
505 * On the positive side of the starting location.
506 */
507 if (i >= 0) {
508 /*
509 * Try to allocate an extent starting in
510 * this block.
511 */
512 error = xfs_rtallocate_extent_block(args,
513 bbno + i, minlen, maxavail, len,
514 &n, prod, &r);
515 if (error) {
516 return error;
517 }
518 /*
519 * If it worked, return it.
520 */
521 if (r != NULLRTEXTNO) {
522 *rtx = r;
523 return 0;
524 }
525 }
526 /*
527 * On the negative side of the starting location.
528 */
529 else { /* i < 0 */
530 int maxblocks;
531
532 /*
533 * Loop backwards to find the end of the extent
534 * we found in the realtime summary.
535 *
536 * maxblocks is the maximum possible number of
537 * bitmap blocks from the start of the extent
538 * to the end of the extent.
539 */
540 if (maxlog == 0)
541 maxblocks = 0;
542 else if (maxlog < mp->m_blkbit_log)
543 maxblocks = 1;
544 else
545 maxblocks = 2 << (maxlog - mp->m_blkbit_log);
546
547 /*
548 * We need to check bbno + i + maxblocks down to
549 * bbno + i. We already checked bbno down to
550 * bbno + j + 1, so we don't need to check those
551 * again.
552 */
553 j = min(i + maxblocks, j);
554 for (; j >= i; j--) {
555 error = xfs_rtallocate_extent_block(args,
556 bbno + j, minlen,
557 maxavail, len, &n, prod,
558 &r);
559 if (error) {
560 return error;
561 }
562 /*
563 * If it works, return the extent.
564 */
565 if (r != NULLRTEXTNO) {
566 *rtx = r;
567 return 0;
568 }
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 *rtx = NULLRTEXTNO;
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 */
611STATIC int
612xfs_rtallocate_extent_size(
613 struct xfs_rtalloc_args *args,
614 xfs_rtxlen_t minlen, /* minimum length to allocate */
615 xfs_rtxlen_t maxlen, /* maximum length to allocate */
616 xfs_rtxlen_t *len, /* out: actual length allocated */
617 xfs_rtxlen_t prod, /* extent product factor */
618 xfs_rtxnum_t *rtx) /* out: start rtext allocated */
619{
620 struct xfs_mount *mp = args->mp;
621 int error;
622 xfs_fileoff_t i; /* bitmap block number */
623 int l; /* level number (loop control) */
624 xfs_rtxnum_t n; /* next rtext to be tried */
625 xfs_rtxnum_t r; /* result rtext number */
626 xfs_suminfo_t sum; /* summary information for extents */
627
628 ASSERT(minlen % prod == 0);
629 ASSERT(maxlen % prod == 0);
630 ASSERT(maxlen != 0);
631
632 /*
633 * Loop over all the levels starting with maxlen.
634 * At each level, look at all the bitmap blocks, to see if there
635 * are extents starting there that are long enough (>= maxlen).
636 * Note, only on the initial level can the allocation fail if
637 * the summary says there's an extent.
638 */
639 for (l = xfs_highbit32(maxlen); l < mp->m_rsumlevels; l++) {
640 /*
641 * Loop over all the bitmap blocks.
642 */
643 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
644 /*
645 * Get the summary for this level/block.
646 */
647 error = xfs_rtget_summary(args, l, i, &sum);
648 if (error) {
649 return error;
650 }
651 /*
652 * Nothing there, on to the next block.
653 */
654 if (!sum)
655 continue;
656 /*
657 * Try allocating the extent.
658 */
659 error = xfs_rtallocate_extent_block(args, i, maxlen,
660 maxlen, len, &n, prod, &r);
661 if (error) {
662 return error;
663 }
664 /*
665 * If it worked, return that.
666 */
667 if (r != NULLRTEXTNO) {
668 *rtx = r;
669 return 0;
670 }
671 /*
672 * If the "next block to try" returned from the
673 * allocator is beyond the next bitmap block,
674 * skip to that bitmap block.
675 */
676 if (xfs_rtx_to_rbmblock(mp, n) > i + 1)
677 i = xfs_rtx_to_rbmblock(mp, n) - 1;
678 }
679 }
680 /*
681 * Didn't find any maxlen blocks. Try smaller ones, unless
682 * we're asking for a fixed size extent.
683 */
684 if (minlen > --maxlen) {
685 *rtx = NULLRTEXTNO;
686 return 0;
687 }
688 ASSERT(minlen != 0);
689 ASSERT(maxlen != 0);
690
691 /*
692 * Loop over sizes, from maxlen down to minlen.
693 * This time, when we do the allocations, allow smaller ones
694 * to succeed.
695 */
696 for (l = xfs_highbit32(maxlen); l >= xfs_highbit32(minlen); l--) {
697 /*
698 * Loop over all the bitmap blocks, try an allocation
699 * starting in that block.
700 */
701 for (i = 0; i < mp->m_sb.sb_rbmblocks; i++) {
702 /*
703 * Get the summary information for this level/block.
704 */
705 error = xfs_rtget_summary(args, l, i, &sum);
706 if (error) {
707 return error;
708 }
709 /*
710 * If nothing there, go on to next.
711 */
712 if (!sum)
713 continue;
714 /*
715 * Try the allocation. Make sure the specified
716 * minlen/maxlen are in the possible range for
717 * this summary level.
718 */
719 error = xfs_rtallocate_extent_block(args, i,
720 XFS_RTMAX(minlen, 1 << l),
721 XFS_RTMIN(maxlen, (1 << (l + 1)) - 1),
722 len, &n, prod, &r);
723 if (error) {
724 return error;
725 }
726 /*
727 * If it worked, return that extent.
728 */
729 if (r != NULLRTEXTNO) {
730 *rtx = r;
731 return 0;
732 }
733 /*
734 * If the "next block to try" returned from the
735 * allocator is beyond the next bitmap block,
736 * skip to that bitmap block.
737 */
738 if (xfs_rtx_to_rbmblock(mp, n) > i + 1)
739 i = xfs_rtx_to_rbmblock(mp, n) - 1;
740 }
741 }
742 /*
743 * Got nothing, return failure.
744 */
745 *rtx = NULLRTEXTNO;
746 return 0;
747}
748
749/*
750 * Allocate space to the bitmap or summary file, and zero it, for growfs.
751 */
752STATIC int
753xfs_growfs_rt_alloc(
754 struct xfs_mount *mp, /* file system mount point */
755 xfs_extlen_t oblocks, /* old count of blocks */
756 xfs_extlen_t nblocks, /* new count of blocks */
757 struct xfs_inode *ip) /* inode (bitmap/summary) */
758{
759 xfs_fileoff_t bno; /* block number in file */
760 struct xfs_buf *bp; /* temporary buffer for zeroing */
761 xfs_daddr_t d; /* disk block address */
762 int error; /* error return value */
763 xfs_fsblock_t fsbno; /* filesystem block for bno */
764 struct xfs_bmbt_irec map; /* block map output */
765 int nmap; /* number of block maps */
766 int resblks; /* space reservation */
767 enum xfs_blft buf_type;
768 struct xfs_trans *tp;
769
770 if (ip == mp->m_rsumip)
771 buf_type = XFS_BLFT_RTSUMMARY_BUF;
772 else
773 buf_type = XFS_BLFT_RTBITMAP_BUF;
774
775 /*
776 * Allocate space to the file, as necessary.
777 */
778 while (oblocks < nblocks) {
779 resblks = XFS_GROWFSRT_SPACE_RES(mp, nblocks - oblocks);
780 /*
781 * Reserve space & log for one extent added to the file.
782 */
783 error = xfs_trans_alloc(mp, resp: &M_RES(mp)->tr_growrtalloc, blocks: resblks,
784 rtextents: 0, flags: 0, tpp: &tp);
785 if (error)
786 return error;
787 /*
788 * Lock the inode.
789 */
790 xfs_ilock(ip, XFS_ILOCK_EXCL);
791 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
792
793 error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK,
794 XFS_IEXT_ADD_NOSPLIT_CNT);
795 if (error == -EFBIG)
796 error = xfs_iext_count_upgrade(tp, ip,
797 XFS_IEXT_ADD_NOSPLIT_CNT);
798 if (error)
799 goto out_trans_cancel;
800
801 /*
802 * Allocate blocks to the bitmap file.
803 */
804 nmap = 1;
805 error = xfs_bmapi_write(tp, ip, oblocks, nblocks - oblocks,
806 XFS_BMAPI_METADATA, 0, &map, &nmap);
807 if (!error && nmap < 1)
808 error = -ENOSPC;
809 if (error)
810 goto out_trans_cancel;
811 /*
812 * Free any blocks freed up in the transaction, then commit.
813 */
814 error = xfs_trans_commit(tp);
815 if (error)
816 return error;
817 /*
818 * Now we need to clear the allocated blocks.
819 * Do this one block per transaction, to keep it simple.
820 */
821 for (bno = map.br_startoff, fsbno = map.br_startblock;
822 bno < map.br_startoff + map.br_blockcount;
823 bno++, fsbno++) {
824 /*
825 * Reserve log for one block zeroing.
826 */
827 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtzero,
828 0, 0, 0, &tp);
829 if (error)
830 return error;
831 /*
832 * Lock the bitmap inode.
833 */
834 xfs_ilock(ip, XFS_ILOCK_EXCL);
835 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
836 /*
837 * Get a buffer for the block.
838 */
839 d = XFS_FSB_TO_DADDR(mp, fsbno);
840 error = xfs_trans_get_buf(tp, mp->m_ddev_targp, d,
841 mp->m_bsize, 0, &bp);
842 if (error)
843 goto out_trans_cancel;
844
845 xfs_trans_buf_set_type(tp, bp, buf_type);
846 bp->b_ops = &xfs_rtbuf_ops;
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
864out_trans_cancel:
865 xfs_trans_cancel(tp);
866 return error;
867}
868
869static void
870xfs_alloc_rsum_cache(
871 xfs_mount_t *mp, /* file system mount structure */
872 xfs_extlen_t rbmblocks) /* number of rt bitmap blocks */
873{
874 /*
875 * The rsum cache is initialized to the maximum value, which is
876 * trivially an upper bound on the maximum level with any free extents.
877 * We can continue without the cache if it couldn't be allocated.
878 */
879 mp->m_rsum_cache = kvmalloc(size: rbmblocks, GFP_KERNEL);
880 if (mp->m_rsum_cache)
881 memset(mp->m_rsum_cache, -1, rbmblocks);
882 else
883 xfs_warn(mp, "could not allocate realtime summary cache");
884}
885
886/*
887 * Visible (exported) functions.
888 */
889
890/*
891 * Grow the realtime area of the filesystem.
892 */
893int
894xfs_growfs_rt(
895 xfs_mount_t *mp, /* mount point for filesystem */
896 xfs_growfs_rt_t *in) /* growfs rt input struct */
897{
898 xfs_fileoff_t bmbno; /* bitmap block number */
899 struct xfs_buf *bp; /* temporary buffer */
900 int error; /* error return value */
901 xfs_mount_t *nmp; /* new (fake) mount structure */
902 xfs_rfsblock_t nrblocks; /* new number of realtime blocks */
903 xfs_extlen_t nrbmblocks; /* new number of rt bitmap blocks */
904 xfs_rtxnum_t nrextents; /* new number of realtime extents */
905 uint8_t nrextslog; /* new log2 of sb_rextents */
906 xfs_extlen_t nrsumblocks; /* new number of summary blocks */
907 uint nrsumlevels; /* new rt summary levels */
908 uint nrsumsize; /* new size of rt summary, bytes */
909 xfs_sb_t *nsbp; /* new superblock */
910 xfs_extlen_t rbmblocks; /* current number of rt bitmap blocks */
911 xfs_extlen_t rsumblocks; /* current number of rt summary blks */
912 xfs_sb_t *sbp; /* old superblock */
913 uint8_t *rsum_cache; /* old summary cache */
914
915 sbp = &mp->m_sb;
916
917 if (!capable(CAP_SYS_ADMIN))
918 return -EPERM;
919
920 /* Needs to have been mounted with an rt device. */
921 if (!XFS_IS_REALTIME_MOUNT(mp))
922 return -EINVAL;
923 /*
924 * Mount should fail if the rt bitmap/summary files don't load, but
925 * we'll check anyway.
926 */
927 if (!mp->m_rbmip || !mp->m_rsumip)
928 return -EINVAL;
929
930 /* Shrink not supported. */
931 if (in->newblocks <= sbp->sb_rblocks)
932 return -EINVAL;
933
934 /* Can only change rt extent size when adding rt volume. */
935 if (sbp->sb_rblocks > 0 && in->extsize != sbp->sb_rextsize)
936 return -EINVAL;
937
938 /* Range check the extent size. */
939 if (XFS_FSB_TO_B(mp, in->extsize) > XFS_MAX_RTEXTSIZE ||
940 XFS_FSB_TO_B(mp, in->extsize) < XFS_MIN_RTEXTSIZE)
941 return -EINVAL;
942
943 /* Unsupported realtime features. */
944 if (xfs_has_rmapbt(mp) || xfs_has_reflink(mp) || xfs_has_quota(mp))
945 return -EOPNOTSUPP;
946
947 nrblocks = in->newblocks;
948 error = xfs_sb_validate_fsb_count(sbp, nrblocks);
949 if (error)
950 return error;
951 /*
952 * Read in the last block of the device, make sure it exists.
953 */
954 error = xfs_buf_read_uncached(mp->m_rtdev_targp,
955 XFS_FSB_TO_BB(mp, nrblocks - 1),
956 XFS_FSB_TO_BB(mp, 1), 0, &bp, NULL);
957 if (error)
958 return error;
959 xfs_buf_relse(bp);
960
961 /*
962 * Calculate new parameters. These are the final values to be reached.
963 */
964 nrextents = nrblocks;
965 do_div(nrextents, in->extsize);
966 nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents);
967 nrextslog = xfs_highbit32(nrextents);
968 nrsumlevels = nrextslog + 1;
969 nrsumblocks = xfs_rtsummary_blockcount(mp, nrsumlevels, nrbmblocks);
970 nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
971 /*
972 * New summary size can't be more than half the size of
973 * the log. This prevents us from getting a log overflow,
974 * since we'll log basically the whole summary file at once.
975 */
976 if (nrsumblocks > (mp->m_sb.sb_logblocks >> 1))
977 return -EINVAL;
978 /*
979 * Get the old block counts for bitmap and summary inodes.
980 * These can't change since other growfs callers are locked out.
981 */
982 rbmblocks = XFS_B_TO_FSB(mp, mp->m_rbmip->i_disk_size);
983 rsumblocks = XFS_B_TO_FSB(mp, mp->m_rsumip->i_disk_size);
984 /*
985 * Allocate space to the bitmap and summary files, as necessary.
986 */
987 error = xfs_growfs_rt_alloc(mp, rbmblocks, nrbmblocks, mp->m_rbmip);
988 if (error)
989 return error;
990 error = xfs_growfs_rt_alloc(mp, rsumblocks, nrsumblocks, mp->m_rsumip);
991 if (error)
992 return error;
993
994 rsum_cache = mp->m_rsum_cache;
995 if (nrbmblocks != sbp->sb_rbmblocks)
996 xfs_alloc_rsum_cache(mp, nrbmblocks);
997
998 /*
999 * Allocate a new (fake) mount/sb.
1000 */
1001 nmp = kmem_alloc(sizeof(*nmp), 0);
1002 /*
1003 * Loop over the bitmap blocks.
1004 * We will do everything one bitmap block at a time.
1005 * Skip the current block if it is exactly full.
1006 * This also deals with the case where there were no rtextents before.
1007 */
1008 for (bmbno = sbp->sb_rbmblocks -
1009 ((sbp->sb_rextents & ((1 << mp->m_blkbit_log) - 1)) != 0);
1010 bmbno < nrbmblocks;
1011 bmbno++) {
1012 struct xfs_rtalloc_args args = {
1013 .mp = mp,
1014 };
1015 struct xfs_rtalloc_args nargs = {
1016 .mp = nmp,
1017 };
1018 struct xfs_trans *tp;
1019 xfs_rfsblock_t nrblocks_step;
1020
1021 *nmp = *mp;
1022 nsbp = &nmp->m_sb;
1023 /*
1024 * Calculate new sb and mount fields for this round.
1025 */
1026 nsbp->sb_rextsize = in->extsize;
1027 nmp->m_rtxblklog = -1; /* don't use shift or masking */
1028 nsbp->sb_rbmblocks = bmbno + 1;
1029 nrblocks_step = (bmbno + 1) * NBBY * nsbp->sb_blocksize *
1030 nsbp->sb_rextsize;
1031 nsbp->sb_rblocks = min(nrblocks, nrblocks_step);
1032 nsbp->sb_rextents = xfs_rtb_to_rtx(nmp, nsbp->sb_rblocks);
1033 ASSERT(nsbp->sb_rextents != 0);
1034 nsbp->sb_rextslog = xfs_highbit32(nsbp->sb_rextents);
1035 nrsumlevels = nmp->m_rsumlevels = nsbp->sb_rextslog + 1;
1036 nrsumblocks = xfs_rtsummary_blockcount(mp, nrsumlevels,
1037 nsbp->sb_rbmblocks);
1038 nmp->m_rsumsize = nrsumsize = XFS_FSB_TO_B(mp, nrsumblocks);
1039 /*
1040 * Start a transaction, get the log reservation.
1041 */
1042 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_growrtfree, 0, 0, 0,
1043 &tp);
1044 if (error)
1045 break;
1046 args.tp = tp;
1047 nargs.tp = tp;
1048
1049 /*
1050 * Lock out other callers by grabbing the bitmap inode lock.
1051 */
1052 xfs_ilock(mp->m_rbmip, XFS_ILOCK_EXCL | XFS_ILOCK_RTBITMAP);
1053 xfs_trans_ijoin(tp, mp->m_rbmip, XFS_ILOCK_EXCL);
1054 /*
1055 * Update the bitmap inode's size ondisk and incore. We need
1056 * to update the incore size so that inode inactivation won't
1057 * punch what it thinks are "posteof" blocks.
1058 */
1059 mp->m_rbmip->i_disk_size =
1060 nsbp->sb_rbmblocks * nsbp->sb_blocksize;
1061 i_size_write(VFS_I(mp->m_rbmip), mp->m_rbmip->i_disk_size);
1062 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1063 /*
1064 * Get the summary inode into the transaction.
1065 */
1066 xfs_ilock(mp->m_rsumip, XFS_ILOCK_EXCL | XFS_ILOCK_RTSUM);
1067 xfs_trans_ijoin(tp, mp->m_rsumip, XFS_ILOCK_EXCL);
1068 /*
1069 * Update the summary inode's size. We need to update the
1070 * incore size so that inode inactivation won't punch what it
1071 * thinks are "posteof" blocks.
1072 */
1073 mp->m_rsumip->i_disk_size = nmp->m_rsumsize;
1074 i_size_write(VFS_I(mp->m_rsumip), mp->m_rsumip->i_disk_size);
1075 xfs_trans_log_inode(tp, mp->m_rsumip, XFS_ILOG_CORE);
1076 /*
1077 * Copy summary data from old to new sizes.
1078 * Do this when the real size (not block-aligned) changes.
1079 */
1080 if (sbp->sb_rbmblocks != nsbp->sb_rbmblocks ||
1081 mp->m_rsumlevels != nmp->m_rsumlevels) {
1082 error = xfs_rtcopy_summary(&args, &nargs);
1083 if (error)
1084 goto error_cancel;
1085 }
1086 /*
1087 * Update superblock fields.
1088 */
1089 if (nsbp->sb_rextsize != sbp->sb_rextsize)
1090 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSIZE,
1091 nsbp->sb_rextsize - sbp->sb_rextsize);
1092 if (nsbp->sb_rbmblocks != sbp->sb_rbmblocks)
1093 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBMBLOCKS,
1094 nsbp->sb_rbmblocks - sbp->sb_rbmblocks);
1095 if (nsbp->sb_rblocks != sbp->sb_rblocks)
1096 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RBLOCKS,
1097 nsbp->sb_rblocks - sbp->sb_rblocks);
1098 if (nsbp->sb_rextents != sbp->sb_rextents)
1099 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTENTS,
1100 nsbp->sb_rextents - sbp->sb_rextents);
1101 if (nsbp->sb_rextslog != sbp->sb_rextslog)
1102 xfs_trans_mod_sb(tp, XFS_TRANS_SB_REXTSLOG,
1103 nsbp->sb_rextslog - sbp->sb_rextslog);
1104 /*
1105 * Free new extent.
1106 */
1107 error = xfs_rtfree_range(&nargs, sbp->sb_rextents,
1108 nsbp->sb_rextents - sbp->sb_rextents);
1109 xfs_rtbuf_cache_relse(&nargs);
1110 if (error) {
1111error_cancel:
1112 xfs_trans_cancel(tp);
1113 break;
1114 }
1115 /*
1116 * Mark more blocks free in the superblock.
1117 */
1118 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS,
1119 nsbp->sb_rextents - sbp->sb_rextents);
1120 /*
1121 * Update mp values into the real mp structure.
1122 */
1123 mp->m_rsumlevels = nrsumlevels;
1124 mp->m_rsumsize = nrsumsize;
1125
1126 error = xfs_trans_commit(tp);
1127 if (error)
1128 break;
1129
1130 /* Ensure the mount RT feature flag is now set. */
1131 mp->m_features |= XFS_FEAT_REALTIME;
1132 }
1133 if (error)
1134 goto out_free;
1135
1136 /* Update secondary superblocks now the physical grow has completed */
1137 error = xfs_update_secondary_sbs(mp);
1138
1139out_free:
1140 /*
1141 * Free the fake mp structure.
1142 */
1143 kmem_free(ptr: nmp);
1144
1145 /*
1146 * If we had to allocate a new rsum_cache, we either need to free the
1147 * old one (if we succeeded) or free the new one and restore the old one
1148 * (if there was an error).
1149 */
1150 if (rsum_cache != mp->m_rsum_cache) {
1151 if (error) {
1152 kmem_free(ptr: mp->m_rsum_cache);
1153 mp->m_rsum_cache = rsum_cache;
1154 } else {
1155 kmem_free(ptr: rsum_cache);
1156 }
1157 }
1158
1159 return error;
1160}
1161
1162/*
1163 * Allocate an extent in the realtime subvolume, with the usual allocation
1164 * parameters. The length units are all in realtime extents, as is the
1165 * result block number.
1166 */
1167int
1168xfs_rtallocate_extent(
1169 struct xfs_trans *tp,
1170 xfs_rtxnum_t start, /* starting rtext number to allocate */
1171 xfs_rtxlen_t minlen, /* minimum length to allocate */
1172 xfs_rtxlen_t maxlen, /* maximum length to allocate */
1173 xfs_rtxlen_t *len, /* out: actual length allocated */
1174 int wasdel, /* was a delayed allocation extent */
1175 xfs_rtxlen_t prod, /* extent product factor */
1176 xfs_rtxnum_t *rtblock) /* out: start rtext allocated */
1177{
1178 struct xfs_rtalloc_args args = {
1179 .mp = tp->t_mountp,
1180 .tp = tp,
1181 };
1182 int error; /* error value */
1183 xfs_rtxnum_t r; /* result allocated rtext */
1184
1185 ASSERT(xfs_isilocked(args.mp->m_rbmip, XFS_ILOCK_EXCL));
1186 ASSERT(minlen > 0 && minlen <= maxlen);
1187
1188 /*
1189 * If prod is set then figure out what to do to minlen and maxlen.
1190 */
1191 if (prod > 1) {
1192 xfs_rtxlen_t i;
1193
1194 if ((i = maxlen % prod))
1195 maxlen -= i;
1196 if ((i = minlen % prod))
1197 minlen += prod - i;
1198 if (maxlen < minlen) {
1199 *rtblock = NULLRTEXTNO;
1200 return 0;
1201 }
1202 }
1203
1204retry:
1205 if (start == 0) {
1206 error = xfs_rtallocate_extent_size(&args, minlen,
1207 maxlen, len, prod, &r);
1208 } else {
1209 error = xfs_rtallocate_extent_near(&args, start, minlen,
1210 maxlen, len, prod, &r);
1211 }
1212
1213 xfs_rtbuf_cache_relse(&args);
1214 if (error)
1215 return error;
1216
1217 /*
1218 * If it worked, update the superblock.
1219 */
1220 if (r != NULLRTEXTNO) {
1221 long slen = (long)*len;
1222
1223 ASSERT(*len >= minlen && *len <= maxlen);
1224 if (wasdel)
1225 xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FREXTENTS, -slen);
1226 else
1227 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, -slen);
1228 } else if (prod > 1) {
1229 prod = 1;
1230 goto retry;
1231 }
1232
1233 *rtblock = r;
1234 return 0;
1235}
1236
1237/*
1238 * Initialize realtime fields in the mount structure.
1239 */
1240int /* error */
1241xfs_rtmount_init(
1242 struct xfs_mount *mp) /* file system mount structure */
1243{
1244 struct xfs_buf *bp; /* buffer for last block of subvolume */
1245 struct xfs_sb *sbp; /* filesystem superblock copy in mount */
1246 xfs_daddr_t d; /* address of last block of subvolume */
1247 unsigned int rsumblocks;
1248 int error;
1249
1250 sbp = &mp->m_sb;
1251 if (sbp->sb_rblocks == 0)
1252 return 0;
1253 if (mp->m_rtdev_targp == NULL) {
1254 xfs_warn(mp,
1255 "Filesystem has a realtime volume, use rtdev=device option");
1256 return -ENODEV;
1257 }
1258 mp->m_rsumlevels = sbp->sb_rextslog + 1;
1259 rsumblocks = xfs_rtsummary_blockcount(mp, mp->m_rsumlevels,
1260 mp->m_sb.sb_rbmblocks);
1261 mp->m_rsumsize = XFS_FSB_TO_B(mp, rsumblocks);
1262 mp->m_rbmip = mp->m_rsumip = NULL;
1263 /*
1264 * Check that the realtime section is an ok size.
1265 */
1266 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_rblocks);
1267 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_rblocks) {
1268 xfs_warn(mp, "realtime mount -- %llu != %llu",
1269 (unsigned long long) XFS_BB_TO_FSB(mp, d),
1270 (unsigned long long) mp->m_sb.sb_rblocks);
1271 return -EFBIG;
1272 }
1273 error = xfs_buf_read_uncached(target: mp->m_rtdev_targp,
1274 daddr: d - XFS_FSB_TO_BB(mp, 1),
1275 numblks: XFS_FSB_TO_BB(mp, 1), flags: 0, bpp: &bp, NULL);
1276 if (error) {
1277 xfs_warn(mp, "realtime device size check failed");
1278 return error;
1279 }
1280 xfs_buf_relse(bp);
1281 return 0;
1282}
1283
1284static int
1285xfs_rtalloc_count_frextent(
1286 struct xfs_mount *mp,
1287 struct xfs_trans *tp,
1288 const struct xfs_rtalloc_rec *rec,
1289 void *priv)
1290{
1291 uint64_t *valp = priv;
1292
1293 *valp += rec->ar_extcount;
1294 return 0;
1295}
1296
1297/*
1298 * Reinitialize the number of free realtime extents from the realtime bitmap.
1299 * Callers must ensure that there is no other activity in the filesystem.
1300 */
1301int
1302xfs_rtalloc_reinit_frextents(
1303 struct xfs_mount *mp)
1304{
1305 uint64_t val = 0;
1306 int error;
1307
1308 xfs_ilock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
1309 error = xfs_rtalloc_query_all(mp, NULL, xfs_rtalloc_count_frextent,
1310 &val);
1311 xfs_iunlock(mp->m_rbmip, XFS_ILOCK_SHARED | XFS_ILOCK_RTBITMAP);
1312 if (error)
1313 return error;
1314
1315 spin_lock(lock: &mp->m_sb_lock);
1316 mp->m_sb.sb_frextents = val;
1317 spin_unlock(lock: &mp->m_sb_lock);
1318 percpu_counter_set(fbc: &mp->m_frextents, amount: mp->m_sb.sb_frextents);
1319 return 0;
1320}
1321
1322/*
1323 * Read in the bmbt of an rt metadata inode so that we never have to load them
1324 * at runtime. This enables the use of shared ILOCKs for rtbitmap scans. Use
1325 * an empty transaction to avoid deadlocking on loops in the bmbt.
1326 */
1327static inline int
1328xfs_rtmount_iread_extents(
1329 struct xfs_inode *ip,
1330 unsigned int lock_class)
1331{
1332 struct xfs_trans *tp;
1333 int error;
1334
1335 error = xfs_trans_alloc_empty(mp: ip->i_mount, tpp: &tp);
1336 if (error)
1337 return error;
1338
1339 xfs_ilock(ip, XFS_ILOCK_EXCL | lock_class);
1340
1341 error = xfs_iread_extents(tp, ip, XFS_DATA_FORK);
1342 if (error)
1343 goto out_unlock;
1344
1345 if (xfs_inode_has_attr_fork(ip)) {
1346 error = xfs_iread_extents(tp, ip, XFS_ATTR_FORK);
1347 if (error)
1348 goto out_unlock;
1349 }
1350
1351out_unlock:
1352 xfs_iunlock(ip, XFS_ILOCK_EXCL | lock_class);
1353 xfs_trans_cancel(tp);
1354 return error;
1355}
1356
1357/*
1358 * Get the bitmap and summary inodes and the summary cache into the mount
1359 * structure at mount time.
1360 */
1361int /* error */
1362xfs_rtmount_inodes(
1363 xfs_mount_t *mp) /* file system mount structure */
1364{
1365 int error; /* error return value */
1366 xfs_sb_t *sbp;
1367
1368 sbp = &mp->m_sb;
1369 error = xfs_iget(mp, NULL, sbp->sb_rbmino, 0, 0, &mp->m_rbmip);
1370 if (error)
1371 return error;
1372 ASSERT(mp->m_rbmip != NULL);
1373
1374 error = xfs_rtmount_iread_extents(ip: mp->m_rbmip, XFS_ILOCK_RTBITMAP);
1375 if (error)
1376 goto out_rele_bitmap;
1377
1378 error = xfs_iget(mp, NULL, sbp->sb_rsumino, 0, 0, &mp->m_rsumip);
1379 if (error)
1380 goto out_rele_bitmap;
1381 ASSERT(mp->m_rsumip != NULL);
1382
1383 error = xfs_rtmount_iread_extents(ip: mp->m_rsumip, XFS_ILOCK_RTSUM);
1384 if (error)
1385 goto out_rele_summary;
1386
1387 xfs_alloc_rsum_cache(mp, sbp->sb_rbmblocks);
1388 return 0;
1389
1390out_rele_summary:
1391 xfs_irele(ip: mp->m_rsumip);
1392out_rele_bitmap:
1393 xfs_irele(ip: mp->m_rbmip);
1394 return error;
1395}
1396
1397void
1398xfs_rtunmount_inodes(
1399 struct xfs_mount *mp)
1400{
1401 kmem_free(ptr: mp->m_rsum_cache);
1402 if (mp->m_rbmip)
1403 xfs_irele(ip: mp->m_rbmip);
1404 if (mp->m_rsumip)
1405 xfs_irele(ip: mp->m_rsumip);
1406}
1407
1408/*
1409 * Pick an extent for allocation at the start of a new realtime file.
1410 * Use the sequence number stored in the atime field of the bitmap inode.
1411 * Translate this to a fraction of the rtextents, and return the product
1412 * of rtextents and the fraction.
1413 * The fraction sequence is 0, 1/2, 1/4, 3/4, 1/8, ..., 7/8, 1/16, ...
1414 */
1415int /* error */
1416xfs_rtpick_extent(
1417 xfs_mount_t *mp, /* file system mount point */
1418 xfs_trans_t *tp, /* transaction pointer */
1419 xfs_rtxlen_t len, /* allocation length (rtextents) */
1420 xfs_rtxnum_t *pick) /* result rt extent */
1421{
1422 xfs_rtxnum_t b; /* result rtext */
1423 int log2; /* log of sequence number */
1424 uint64_t resid; /* residual after log removed */
1425 uint64_t seq; /* sequence number of file creation */
1426 struct timespec64 ts; /* timespec in inode */
1427
1428 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
1429
1430 ts = inode_get_atime(inode: VFS_I(ip: mp->m_rbmip));
1431 if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM)) {
1432 mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
1433 seq = 0;
1434 } else {
1435 seq = ts.tv_sec;
1436 }
1437 if ((log2 = xfs_highbit64(seq)) == -1)
1438 b = 0;
1439 else {
1440 resid = seq - (1ULL << log2);
1441 b = (mp->m_sb.sb_rextents * ((resid << 1) + 1ULL)) >>
1442 (log2 + 1);
1443 if (b >= mp->m_sb.sb_rextents)
1444 div64_u64_rem(b, mp->m_sb.sb_rextents, &b);
1445 if (b + len > mp->m_sb.sb_rextents)
1446 b = mp->m_sb.sb_rextents - len;
1447 }
1448 ts.tv_sec = seq + 1;
1449 inode_set_atime_to_ts(inode: VFS_I(ip: mp->m_rbmip), ts);
1450 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1451 *pick = b;
1452 return 0;
1453}
1454

source code of linux/fs/xfs/xfs_rtalloc.c