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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_trans.h"
17#include "xfs_rtalloc.h"
18#include "xfs_error.h"
19#include "xfs_rtbitmap.h"
20
21/*
22 * Realtime allocator bitmap functions shared with userspace.
23 */
24
25/*
26 * Real time buffers need verifiers to avoid runtime warnings during IO.
27 * We don't have anything to verify, however, so these are just dummy
28 * operations.
29 */
30static void
31xfs_rtbuf_verify_read(
32 struct xfs_buf *bp)
33{
34 return;
35}
36
37static void
38xfs_rtbuf_verify_write(
39 struct xfs_buf *bp)
40{
41 return;
42}
43
44const struct xfs_buf_ops xfs_rtbuf_ops = {
45 .name = "rtbuf",
46 .verify_read = xfs_rtbuf_verify_read,
47 .verify_write = xfs_rtbuf_verify_write,
48};
49
50/* Release cached rt bitmap and summary buffers. */
51void
52xfs_rtbuf_cache_relse(
53 struct xfs_rtalloc_args *args)
54{
55 if (args->rbmbp) {
56 xfs_trans_brelse(args->tp, args->rbmbp);
57 args->rbmbp = NULL;
58 args->rbmoff = NULLFILEOFF;
59 }
60 if (args->sumbp) {
61 xfs_trans_brelse(args->tp, args->sumbp);
62 args->sumbp = NULL;
63 args->sumoff = NULLFILEOFF;
64 }
65}
66
67/*
68 * Get a buffer for the bitmap or summary file block specified.
69 * The buffer is returned read and locked.
70 */
71int
72xfs_rtbuf_get(
73 struct xfs_rtalloc_args *args,
74 xfs_fileoff_t block, /* block number in bitmap or summary */
75 int issum) /* is summary not bitmap */
76{
77 struct xfs_mount *mp = args->mp;
78 struct xfs_buf **cbpp; /* cached block buffer */
79 xfs_fileoff_t *coffp; /* cached block number */
80 struct xfs_buf *bp; /* block buffer, result */
81 struct xfs_inode *ip; /* bitmap or summary inode */
82 struct xfs_bmbt_irec map;
83 enum xfs_blft type;
84 int nmap = 1;
85 int error;
86
87 if (issum) {
88 cbpp = &args->sumbp;
89 coffp = &args->sumoff;
90 ip = mp->m_rsumip;
91 type = XFS_BLFT_RTSUMMARY_BUF;
92 } else {
93 cbpp = &args->rbmbp;
94 coffp = &args->rbmoff;
95 ip = mp->m_rbmip;
96 type = XFS_BLFT_RTBITMAP_BUF;
97 }
98
99 /*
100 * If we have a cached buffer, and the block number matches, use that.
101 */
102 if (*cbpp && *coffp == block)
103 return 0;
104
105 /*
106 * Otherwise we have to have to get the buffer. If there was an old
107 * one, get rid of it first.
108 */
109 if (*cbpp) {
110 xfs_trans_brelse(args->tp, *cbpp);
111 *cbpp = NULL;
112 }
113
114 error = xfs_bmapi_read(ip, block, 1, &map, &nmap, 0);
115 if (error)
116 return error;
117
118 if (XFS_IS_CORRUPT(mp, nmap == 0 || !xfs_bmap_is_written_extent(&map)))
119 return -EFSCORRUPTED;
120
121 ASSERT(map.br_startblock != NULLFSBLOCK);
122 error = xfs_trans_read_buf(mp, args->tp, mp->m_ddev_targp,
123 XFS_FSB_TO_DADDR(mp, map.br_startblock),
124 mp->m_bsize, 0, &bp, &xfs_rtbuf_ops);
125 if (error)
126 return error;
127
128 xfs_trans_buf_set_type(args->tp, bp, type);
129 *cbpp = bp;
130 *coffp = block;
131 return 0;
132}
133
134/*
135 * Searching backward from start to limit, find the first block whose
136 * allocated/free state is different from start's.
137 */
138int
139xfs_rtfind_back(
140 struct xfs_rtalloc_args *args,
141 xfs_rtxnum_t start, /* starting rtext to look at */
142 xfs_rtxnum_t limit, /* last rtext to look at */
143 xfs_rtxnum_t *rtx) /* out: start rtext found */
144{
145 struct xfs_mount *mp = args->mp;
146 int bit; /* bit number in the word */
147 xfs_fileoff_t block; /* bitmap block number */
148 int error; /* error value */
149 xfs_rtxnum_t firstbit; /* first useful bit in the word */
150 xfs_rtxnum_t i; /* current bit number rel. to start */
151 xfs_rtxnum_t len; /* length of inspected area */
152 xfs_rtword_t mask; /* mask of relevant bits for value */
153 xfs_rtword_t want; /* mask for "good" values */
154 xfs_rtword_t wdiff; /* difference from wanted value */
155 xfs_rtword_t incore;
156 unsigned int word; /* word number in the buffer */
157
158 /*
159 * Compute and read in starting bitmap block for starting block.
160 */
161 block = xfs_rtx_to_rbmblock(mp, start);
162 error = xfs_rtbitmap_read_buf(args, block);
163 if (error)
164 return error;
165
166 /*
167 * Get the first word's index & point to it.
168 */
169 word = xfs_rtx_to_rbmword(mp, start);
170 bit = (int)(start & (XFS_NBWORD - 1));
171 len = start - limit + 1;
172 /*
173 * Compute match value, based on the bit at start: if 1 (free)
174 * then all-ones, else all-zeroes.
175 */
176 incore = xfs_rtbitmap_getword(args, word);
177 want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
178 /*
179 * If the starting position is not word-aligned, deal with the
180 * partial word.
181 */
182 if (bit < XFS_NBWORD - 1) {
183 /*
184 * Calculate first (leftmost) bit number to look at,
185 * and mask for all the relevant bits in this word.
186 */
187 firstbit = max_t(xfs_srtblock_t, bit - len + 1, 0);
188 mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
189 firstbit;
190 /*
191 * Calculate the difference between the value there
192 * and what we're looking for.
193 */
194 if ((wdiff = (incore ^ want) & mask)) {
195 /*
196 * Different. Mark where we are and return.
197 */
198 i = bit - xfs_highbit32(wdiff);
199 *rtx = start - i + 1;
200 return 0;
201 }
202 i = bit - firstbit + 1;
203 /*
204 * Go on to previous block if that's where the previous word is
205 * and we need the previous word.
206 */
207 if (--word == -1 && i < len) {
208 /*
209 * If done with this block, get the previous one.
210 */
211 error = xfs_rtbitmap_read_buf(args, --block);
212 if (error)
213 return error;
214
215 word = mp->m_blockwsize - 1;
216 }
217 } else {
218 /*
219 * Starting on a word boundary, no partial word.
220 */
221 i = 0;
222 }
223 /*
224 * Loop over whole words in buffers. When we use up one buffer
225 * we move on to the previous one.
226 */
227 while (len - i >= XFS_NBWORD) {
228 /*
229 * Compute difference between actual and desired value.
230 */
231 incore = xfs_rtbitmap_getword(args, word);
232 if ((wdiff = incore ^ want)) {
233 /*
234 * Different, mark where we are and return.
235 */
236 i += XFS_NBWORD - 1 - xfs_highbit32(wdiff);
237 *rtx = start - i + 1;
238 return 0;
239 }
240 i += XFS_NBWORD;
241 /*
242 * Go on to previous block if that's where the previous word is
243 * and we need the previous word.
244 */
245 if (--word == -1 && i < len) {
246 /*
247 * If done with this block, get the previous one.
248 */
249 error = xfs_rtbitmap_read_buf(args, --block);
250 if (error)
251 return error;
252
253 word = mp->m_blockwsize - 1;
254 }
255 }
256 /*
257 * If not ending on a word boundary, deal with the last
258 * (partial) word.
259 */
260 if (len - i) {
261 /*
262 * Calculate first (leftmost) bit number to look at,
263 * and mask for all the relevant bits in this word.
264 */
265 firstbit = XFS_NBWORD - (len - i);
266 mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
267 /*
268 * Compute difference between actual and desired value.
269 */
270 incore = xfs_rtbitmap_getword(args, word);
271 if ((wdiff = (incore ^ want) & mask)) {
272 /*
273 * Different, mark where we are and return.
274 */
275 i += XFS_NBWORD - 1 - xfs_highbit32(wdiff);
276 *rtx = start - i + 1;
277 return 0;
278 } else
279 i = len;
280 }
281 /*
282 * No match, return that we scanned the whole area.
283 */
284 *rtx = start - i + 1;
285 return 0;
286}
287
288/*
289 * Searching forward from start to limit, find the first block whose
290 * allocated/free state is different from start's.
291 */
292int
293xfs_rtfind_forw(
294 struct xfs_rtalloc_args *args,
295 xfs_rtxnum_t start, /* starting rtext to look at */
296 xfs_rtxnum_t limit, /* last rtext to look at */
297 xfs_rtxnum_t *rtx) /* out: start rtext found */
298{
299 struct xfs_mount *mp = args->mp;
300 int bit; /* bit number in the word */
301 xfs_fileoff_t block; /* bitmap block number */
302 int error;
303 xfs_rtxnum_t i; /* current bit number rel. to start */
304 xfs_rtxnum_t lastbit;/* last useful bit in the word */
305 xfs_rtxnum_t len; /* length of inspected area */
306 xfs_rtword_t mask; /* mask of relevant bits for value */
307 xfs_rtword_t want; /* mask for "good" values */
308 xfs_rtword_t wdiff; /* difference from wanted value */
309 xfs_rtword_t incore;
310 unsigned int word; /* word number in the buffer */
311
312 /*
313 * Compute and read in starting bitmap block for starting block.
314 */
315 block = xfs_rtx_to_rbmblock(mp, start);
316 error = xfs_rtbitmap_read_buf(args, block);
317 if (error)
318 return error;
319
320 /*
321 * Get the first word's index & point to it.
322 */
323 word = xfs_rtx_to_rbmword(mp, start);
324 bit = (int)(start & (XFS_NBWORD - 1));
325 len = limit - start + 1;
326 /*
327 * Compute match value, based on the bit at start: if 1 (free)
328 * then all-ones, else all-zeroes.
329 */
330 incore = xfs_rtbitmap_getword(args, word);
331 want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
332 /*
333 * If the starting position is not word-aligned, deal with the
334 * partial word.
335 */
336 if (bit) {
337 /*
338 * Calculate last (rightmost) bit number to look at,
339 * and mask for all the relevant bits in this word.
340 */
341 lastbit = min(bit + len, XFS_NBWORD);
342 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
343 /*
344 * Calculate the difference between the value there
345 * and what we're looking for.
346 */
347 if ((wdiff = (incore ^ want) & mask)) {
348 /*
349 * Different. Mark where we are and return.
350 */
351 i = xfs_lowbit32(wdiff) - bit;
352 *rtx = start + i - 1;
353 return 0;
354 }
355 i = lastbit - bit;
356 /*
357 * Go on to next block if that's where the next word is
358 * and we need the next word.
359 */
360 if (++word == mp->m_blockwsize && i < len) {
361 /*
362 * If done with this block, get the previous one.
363 */
364 error = xfs_rtbitmap_read_buf(args, ++block);
365 if (error)
366 return error;
367
368 word = 0;
369 }
370 } else {
371 /*
372 * Starting on a word boundary, no partial word.
373 */
374 i = 0;
375 }
376 /*
377 * Loop over whole words in buffers. When we use up one buffer
378 * we move on to the next one.
379 */
380 while (len - i >= XFS_NBWORD) {
381 /*
382 * Compute difference between actual and desired value.
383 */
384 incore = xfs_rtbitmap_getword(args, word);
385 if ((wdiff = incore ^ want)) {
386 /*
387 * Different, mark where we are and return.
388 */
389 i += xfs_lowbit32(wdiff);
390 *rtx = start + i - 1;
391 return 0;
392 }
393 i += XFS_NBWORD;
394 /*
395 * Go on to next block if that's where the next word is
396 * and we need the next word.
397 */
398 if (++word == mp->m_blockwsize && i < len) {
399 /*
400 * If done with this block, get the next one.
401 */
402 error = xfs_rtbitmap_read_buf(args, ++block);
403 if (error)
404 return error;
405
406 word = 0;
407 }
408 }
409 /*
410 * If not ending on a word boundary, deal with the last
411 * (partial) word.
412 */
413 if ((lastbit = len - i)) {
414 /*
415 * Calculate mask for all the relevant bits in this word.
416 */
417 mask = ((xfs_rtword_t)1 << lastbit) - 1;
418 /*
419 * Compute difference between actual and desired value.
420 */
421 incore = xfs_rtbitmap_getword(args, word);
422 if ((wdiff = (incore ^ want) & mask)) {
423 /*
424 * Different, mark where we are and return.
425 */
426 i += xfs_lowbit32(wdiff);
427 *rtx = start + i - 1;
428 return 0;
429 } else
430 i = len;
431 }
432 /*
433 * No match, return that we scanned the whole area.
434 */
435 *rtx = start + i - 1;
436 return 0;
437}
438
439/* Log rtsummary counter at @infoword. */
440static inline void
441xfs_trans_log_rtsummary(
442 struct xfs_rtalloc_args *args,
443 unsigned int infoword)
444{
445 struct xfs_buf *bp = args->sumbp;
446 size_t first, last;
447
448 first = (void *)xfs_rsumblock_infoptr(args, infoword) - bp->b_addr;
449 last = first + sizeof(xfs_suminfo_t) - 1;
450
451 xfs_trans_log_buf(args->tp, bp, first, last);
452}
453
454/*
455 * Modify the summary information for a given extent size, bitmap block
456 * combination.
457 */
458int
459xfs_rtmodify_summary(
460 struct xfs_rtalloc_args *args,
461 int log, /* log2 of extent size */
462 xfs_fileoff_t bbno, /* bitmap block number */
463 int delta) /* in/out: summary block number */
464{
465 struct xfs_mount *mp = args->mp;
466 xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
467 unsigned int infoword;
468 xfs_suminfo_t val;
469 int error;
470
471 error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
472 if (error)
473 return error;
474
475 infoword = xfs_rtsumoffs_to_infoword(mp, so);
476 val = xfs_suminfo_add(args, infoword, delta);
477
478 if (mp->m_rsum_cache) {
479 if (val == 0 && log + 1 == mp->m_rsum_cache[bbno])
480 mp->m_rsum_cache[bbno] = log;
481 if (val != 0 && log >= mp->m_rsum_cache[bbno])
482 mp->m_rsum_cache[bbno] = log + 1;
483 }
484
485 xfs_trans_log_rtsummary(args, infoword);
486 return 0;
487}
488
489/*
490 * Read and return the summary information for a given extent size, bitmap block
491 * combination.
492 */
493int
494xfs_rtget_summary(
495 struct xfs_rtalloc_args *args,
496 int log, /* log2 of extent size */
497 xfs_fileoff_t bbno, /* bitmap block number */
498 xfs_suminfo_t *sum) /* out: summary info for this block */
499{
500 struct xfs_mount *mp = args->mp;
501 xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
502 int error;
503
504 error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
505 if (!error)
506 *sum = xfs_suminfo_get(args, xfs_rtsumoffs_to_infoword(mp, so));
507 return error;
508}
509
510/* Log rtbitmap block from the word @from to the byte before @next. */
511static inline void
512xfs_trans_log_rtbitmap(
513 struct xfs_rtalloc_args *args,
514 unsigned int from,
515 unsigned int next)
516{
517 struct xfs_buf *bp = args->rbmbp;
518 size_t first, last;
519
520 first = (void *)xfs_rbmblock_wordptr(args, from) - bp->b_addr;
521 last = ((void *)xfs_rbmblock_wordptr(args, next) - 1) - bp->b_addr;
522
523 xfs_trans_log_buf(args->tp, bp, first, last);
524}
525
526/*
527 * Set the given range of bitmap bits to the given value.
528 * Do whatever I/O and logging is required.
529 */
530int
531xfs_rtmodify_range(
532 struct xfs_rtalloc_args *args,
533 xfs_rtxnum_t start, /* starting rtext to modify */
534 xfs_rtxlen_t len, /* length of extent to modify */
535 int val) /* 1 for free, 0 for allocated */
536{
537 struct xfs_mount *mp = args->mp;
538 int bit; /* bit number in the word */
539 xfs_fileoff_t block; /* bitmap block number */
540 int error;
541 int i; /* current bit number rel. to start */
542 int lastbit; /* last useful bit in word */
543 xfs_rtword_t mask; /* mask of relevant bits for value */
544 xfs_rtword_t incore;
545 unsigned int firstword; /* first word used in the buffer */
546 unsigned int word; /* word number in the buffer */
547
548 /*
549 * Compute starting bitmap block number.
550 */
551 block = xfs_rtx_to_rbmblock(mp, start);
552 /*
553 * Read the bitmap block, and point to its data.
554 */
555 error = xfs_rtbitmap_read_buf(args, block);
556 if (error)
557 return error;
558
559 /*
560 * Compute the starting word's address, and starting bit.
561 */
562 firstword = word = xfs_rtx_to_rbmword(mp, start);
563 bit = (int)(start & (XFS_NBWORD - 1));
564 /*
565 * 0 (allocated) => all zeroes; 1 (free) => all ones.
566 */
567 val = -val;
568 /*
569 * If not starting on a word boundary, deal with the first
570 * (partial) word.
571 */
572 if (bit) {
573 /*
574 * Compute first bit not changed and mask of relevant bits.
575 */
576 lastbit = min(bit + len, XFS_NBWORD);
577 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
578 /*
579 * Set/clear the active bits.
580 */
581 incore = xfs_rtbitmap_getword(args, word);
582 if (val)
583 incore |= mask;
584 else
585 incore &= ~mask;
586 xfs_rtbitmap_setword(args, word, incore);
587 i = lastbit - bit;
588 /*
589 * Go on to the next block if that's where the next word is
590 * and we need the next word.
591 */
592 if (++word == mp->m_blockwsize && i < len) {
593 /*
594 * Log the changed part of this block.
595 * Get the next one.
596 */
597 xfs_trans_log_rtbitmap(args, firstword, word);
598 error = xfs_rtbitmap_read_buf(args, ++block);
599 if (error)
600 return error;
601
602 firstword = word = 0;
603 }
604 } else {
605 /*
606 * Starting on a word boundary, no partial word.
607 */
608 i = 0;
609 }
610 /*
611 * Loop over whole words in buffers. When we use up one buffer
612 * we move on to the next one.
613 */
614 while (len - i >= XFS_NBWORD) {
615 /*
616 * Set the word value correctly.
617 */
618 xfs_rtbitmap_setword(args, word, val);
619 i += XFS_NBWORD;
620 /*
621 * Go on to the next block if that's where the next word is
622 * and we need the next word.
623 */
624 if (++word == mp->m_blockwsize && i < len) {
625 /*
626 * Log the changed part of this block.
627 * Get the next one.
628 */
629 xfs_trans_log_rtbitmap(args, firstword, word);
630 error = xfs_rtbitmap_read_buf(args, ++block);
631 if (error)
632 return error;
633
634 firstword = word = 0;
635 }
636 }
637 /*
638 * If not ending on a word boundary, deal with the last
639 * (partial) word.
640 */
641 if ((lastbit = len - i)) {
642 /*
643 * Compute a mask of relevant bits.
644 */
645 mask = ((xfs_rtword_t)1 << lastbit) - 1;
646 /*
647 * Set/clear the active bits.
648 */
649 incore = xfs_rtbitmap_getword(args, word);
650 if (val)
651 incore |= mask;
652 else
653 incore &= ~mask;
654 xfs_rtbitmap_setword(args, word, incore);
655 word++;
656 }
657 /*
658 * Log any remaining changed bytes.
659 */
660 if (word > firstword)
661 xfs_trans_log_rtbitmap(args, firstword, word);
662 return 0;
663}
664
665/*
666 * Mark an extent specified by start and len freed.
667 * Updates all the summary information as well as the bitmap.
668 */
669int
670xfs_rtfree_range(
671 struct xfs_rtalloc_args *args,
672 xfs_rtxnum_t start, /* starting rtext to free */
673 xfs_rtxlen_t len) /* in/out: summary block number */
674{
675 struct xfs_mount *mp = args->mp;
676 xfs_rtxnum_t end; /* end of the freed extent */
677 int error; /* error value */
678 xfs_rtxnum_t postblock; /* first rtext freed > end */
679 xfs_rtxnum_t preblock; /* first rtext freed < start */
680
681 end = start + len - 1;
682 /*
683 * Modify the bitmap to mark this extent freed.
684 */
685 error = xfs_rtmodify_range(args, start, len, 1);
686 if (error) {
687 return error;
688 }
689 /*
690 * Assume we're freeing out of the middle of an allocated extent.
691 * We need to find the beginning and end of the extent so we can
692 * properly update the summary.
693 */
694 error = xfs_rtfind_back(args, start, 0, &preblock);
695 if (error) {
696 return error;
697 }
698 /*
699 * Find the next allocated block (end of allocated extent).
700 */
701 error = xfs_rtfind_forw(args, end, mp->m_sb.sb_rextents - 1,
702 &postblock);
703 if (error)
704 return error;
705 /*
706 * If there are blocks not being freed at the front of the
707 * old extent, add summary data for them to be allocated.
708 */
709 if (preblock < start) {
710 error = xfs_rtmodify_summary(args,
711 xfs_highbit64(start - preblock),
712 xfs_rtx_to_rbmblock(mp, preblock), -1);
713 if (error) {
714 return error;
715 }
716 }
717 /*
718 * If there are blocks not being freed at the end of the
719 * old extent, add summary data for them to be allocated.
720 */
721 if (postblock > end) {
722 error = xfs_rtmodify_summary(args,
723 xfs_highbit64(postblock - end),
724 xfs_rtx_to_rbmblock(mp, end + 1), -1);
725 if (error) {
726 return error;
727 }
728 }
729 /*
730 * Increment the summary information corresponding to the entire
731 * (new) free extent.
732 */
733 return xfs_rtmodify_summary(args,
734 xfs_highbit64(postblock + 1 - preblock),
735 xfs_rtx_to_rbmblock(mp, preblock), 1);
736}
737
738/*
739 * Check that the given range is either all allocated (val = 0) or
740 * all free (val = 1).
741 */
742int
743xfs_rtcheck_range(
744 struct xfs_rtalloc_args *args,
745 xfs_rtxnum_t start, /* starting rtext number of extent */
746 xfs_rtxlen_t len, /* length of extent */
747 int val, /* 1 for free, 0 for allocated */
748 xfs_rtxnum_t *new, /* out: first rtext not matching */
749 int *stat) /* out: 1 for matches, 0 for not */
750{
751 struct xfs_mount *mp = args->mp;
752 int bit; /* bit number in the word */
753 xfs_fileoff_t block; /* bitmap block number */
754 int error;
755 xfs_rtxnum_t i; /* current bit number rel. to start */
756 xfs_rtxnum_t lastbit; /* last useful bit in word */
757 xfs_rtword_t mask; /* mask of relevant bits for value */
758 xfs_rtword_t wdiff; /* difference from wanted value */
759 xfs_rtword_t incore;
760 unsigned int word; /* word number in the buffer */
761
762 /*
763 * Compute starting bitmap block number
764 */
765 block = xfs_rtx_to_rbmblock(mp, start);
766 /*
767 * Read the bitmap block.
768 */
769 error = xfs_rtbitmap_read_buf(args, block);
770 if (error)
771 return error;
772
773 /*
774 * Compute the starting word's address, and starting bit.
775 */
776 word = xfs_rtx_to_rbmword(mp, start);
777 bit = (int)(start & (XFS_NBWORD - 1));
778 /*
779 * 0 (allocated) => all zero's; 1 (free) => all one's.
780 */
781 val = -val;
782 /*
783 * If not starting on a word boundary, deal with the first
784 * (partial) word.
785 */
786 if (bit) {
787 /*
788 * Compute first bit not examined.
789 */
790 lastbit = min(bit + len, XFS_NBWORD);
791 /*
792 * Mask of relevant bits.
793 */
794 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
795 /*
796 * Compute difference between actual and desired value.
797 */
798 incore = xfs_rtbitmap_getword(args, word);
799 if ((wdiff = (incore ^ val) & mask)) {
800 /*
801 * Different, compute first wrong bit and return.
802 */
803 i = xfs_lowbit32(wdiff) - bit;
804 *new = start + i;
805 *stat = 0;
806 return 0;
807 }
808 i = lastbit - bit;
809 /*
810 * Go on to next block if that's where the next word is
811 * and we need the next word.
812 */
813 if (++word == mp->m_blockwsize && i < len) {
814 /*
815 * If done with this block, get the next one.
816 */
817 error = xfs_rtbitmap_read_buf(args, ++block);
818 if (error)
819 return error;
820
821 word = 0;
822 }
823 } else {
824 /*
825 * Starting on a word boundary, no partial word.
826 */
827 i = 0;
828 }
829 /*
830 * Loop over whole words in buffers. When we use up one buffer
831 * we move on to the next one.
832 */
833 while (len - i >= XFS_NBWORD) {
834 /*
835 * Compute difference between actual and desired value.
836 */
837 incore = xfs_rtbitmap_getword(args, word);
838 if ((wdiff = incore ^ val)) {
839 /*
840 * Different, compute first wrong bit and return.
841 */
842 i += xfs_lowbit32(wdiff);
843 *new = start + i;
844 *stat = 0;
845 return 0;
846 }
847 i += XFS_NBWORD;
848 /*
849 * Go on to next block if that's where the next word is
850 * and we need the next word.
851 */
852 if (++word == mp->m_blockwsize && i < len) {
853 /*
854 * If done with this block, get the next one.
855 */
856 error = xfs_rtbitmap_read_buf(args, ++block);
857 if (error)
858 return error;
859
860 word = 0;
861 }
862 }
863 /*
864 * If not ending on a word boundary, deal with the last
865 * (partial) word.
866 */
867 if ((lastbit = len - i)) {
868 /*
869 * Mask of relevant bits.
870 */
871 mask = ((xfs_rtword_t)1 << lastbit) - 1;
872 /*
873 * Compute difference between actual and desired value.
874 */
875 incore = xfs_rtbitmap_getword(args, word);
876 if ((wdiff = (incore ^ val) & mask)) {
877 /*
878 * Different, compute first wrong bit and return.
879 */
880 i += xfs_lowbit32(wdiff);
881 *new = start + i;
882 *stat = 0;
883 return 0;
884 } else
885 i = len;
886 }
887 /*
888 * Successful, return.
889 */
890 *new = start + i;
891 *stat = 1;
892 return 0;
893}
894
895#ifdef DEBUG
896/*
897 * Check that the given extent (block range) is allocated already.
898 */
899STATIC int
900xfs_rtcheck_alloc_range(
901 struct xfs_rtalloc_args *args,
902 xfs_rtxnum_t start, /* starting rtext number of extent */
903 xfs_rtxlen_t len) /* length of extent */
904{
905 xfs_rtxnum_t new; /* dummy for xfs_rtcheck_range */
906 int stat;
907 int error;
908
909 error = xfs_rtcheck_range(args, start, len, 0, &new, &stat);
910 if (error)
911 return error;
912 ASSERT(stat);
913 return 0;
914}
915#else
916#define xfs_rtcheck_alloc_range(a,b,l) (0)
917#endif
918/*
919 * Free an extent in the realtime subvolume. Length is expressed in
920 * realtime extents, as is the block number.
921 */
922int
923xfs_rtfree_extent(
924 struct xfs_trans *tp, /* transaction pointer */
925 xfs_rtxnum_t start, /* starting rtext number to free */
926 xfs_rtxlen_t len) /* length of extent freed */
927{
928 struct xfs_mount *mp = tp->t_mountp;
929 struct xfs_rtalloc_args args = {
930 .mp = mp,
931 .tp = tp,
932 };
933 int error;
934 struct timespec64 atime;
935
936 ASSERT(mp->m_rbmip->i_itemp != NULL);
937 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
938
939 error = xfs_rtcheck_alloc_range(&args, start, len);
940 if (error)
941 return error;
942
943 /*
944 * Free the range of realtime blocks.
945 */
946 error = xfs_rtfree_range(&args, start, len);
947 if (error)
948 goto out;
949
950 /*
951 * Mark more blocks free in the superblock.
952 */
953 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
954 /*
955 * If we've now freed all the blocks, reset the file sequence
956 * number to 0.
957 */
958 if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
959 mp->m_sb.sb_rextents) {
960 if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM))
961 mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
962
963 atime = inode_get_atime(VFS_I(mp->m_rbmip));
964 atime.tv_sec = 0;
965 inode_set_atime_to_ts(VFS_I(mp->m_rbmip), atime);
966 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
967 }
968 error = 0;
969out:
970 xfs_rtbuf_cache_relse(&args);
971 return error;
972}
973
974/*
975 * Free some blocks in the realtime subvolume. rtbno and rtlen are in units of
976 * rt blocks, not rt extents; must be aligned to the rt extent size; and rtlen
977 * cannot exceed XFS_MAX_BMBT_EXTLEN.
978 */
979int
980xfs_rtfree_blocks(
981 struct xfs_trans *tp,
982 xfs_fsblock_t rtbno,
983 xfs_filblks_t rtlen)
984{
985 struct xfs_mount *mp = tp->t_mountp;
986 xfs_rtxnum_t start;
987 xfs_filblks_t len;
988 xfs_extlen_t mod;
989
990 ASSERT(rtlen <= XFS_MAX_BMBT_EXTLEN);
991
992 len = xfs_rtb_to_rtxrem(mp, rtlen, &mod);
993 if (mod) {
994 ASSERT(mod == 0);
995 return -EIO;
996 }
997
998 start = xfs_rtb_to_rtxrem(mp, rtbno, &mod);
999 if (mod) {
1000 ASSERT(mod == 0);
1001 return -EIO;
1002 }
1003
1004 return xfs_rtfree_extent(tp, start, len);
1005}
1006
1007/* Find all the free records within a given range. */
1008int
1009xfs_rtalloc_query_range(
1010 struct xfs_mount *mp,
1011 struct xfs_trans *tp,
1012 const struct xfs_rtalloc_rec *low_rec,
1013 const struct xfs_rtalloc_rec *high_rec,
1014 xfs_rtalloc_query_range_fn fn,
1015 void *priv)
1016{
1017 struct xfs_rtalloc_args args = {
1018 .mp = mp,
1019 .tp = tp,
1020 };
1021 struct xfs_rtalloc_rec rec;
1022 xfs_rtxnum_t rtstart;
1023 xfs_rtxnum_t rtend;
1024 xfs_rtxnum_t high_key;
1025 int is_free;
1026 int error = 0;
1027
1028 if (low_rec->ar_startext > high_rec->ar_startext)
1029 return -EINVAL;
1030 if (low_rec->ar_startext >= mp->m_sb.sb_rextents ||
1031 low_rec->ar_startext == high_rec->ar_startext)
1032 return 0;
1033
1034 high_key = min(high_rec->ar_startext, mp->m_sb.sb_rextents - 1);
1035
1036 /* Iterate the bitmap, looking for discrepancies. */
1037 rtstart = low_rec->ar_startext;
1038 while (rtstart <= high_key) {
1039 /* Is the first block free? */
1040 error = xfs_rtcheck_range(&args, rtstart, 1, 1, &rtend,
1041 &is_free);
1042 if (error)
1043 break;
1044
1045 /* How long does the extent go for? */
1046 error = xfs_rtfind_forw(&args, rtstart, high_key, &rtend);
1047 if (error)
1048 break;
1049
1050 if (is_free) {
1051 rec.ar_startext = rtstart;
1052 rec.ar_extcount = rtend - rtstart + 1;
1053
1054 error = fn(mp, tp, &rec, priv);
1055 if (error)
1056 break;
1057 }
1058
1059 rtstart = rtend + 1;
1060 }
1061
1062 xfs_rtbuf_cache_relse(&args);
1063 return error;
1064}
1065
1066/* Find all the free records. */
1067int
1068xfs_rtalloc_query_all(
1069 struct xfs_mount *mp,
1070 struct xfs_trans *tp,
1071 xfs_rtalloc_query_range_fn fn,
1072 void *priv)
1073{
1074 struct xfs_rtalloc_rec keys[2];
1075
1076 keys[0].ar_startext = 0;
1077 keys[1].ar_startext = mp->m_sb.sb_rextents - 1;
1078 keys[0].ar_extcount = keys[1].ar_extcount = 0;
1079
1080 return xfs_rtalloc_query_range(mp, tp, &keys[0], &keys[1], fn, priv);
1081}
1082
1083/* Is the given extent all free? */
1084int
1085xfs_rtalloc_extent_is_free(
1086 struct xfs_mount *mp,
1087 struct xfs_trans *tp,
1088 xfs_rtxnum_t start,
1089 xfs_rtxlen_t len,
1090 bool *is_free)
1091{
1092 struct xfs_rtalloc_args args = {
1093 .mp = mp,
1094 .tp = tp,
1095 };
1096 xfs_rtxnum_t end;
1097 int matches;
1098 int error;
1099
1100 error = xfs_rtcheck_range(&args, start, len, 1, &end, &matches);
1101 xfs_rtbuf_cache_relse(&args);
1102 if (error)
1103 return error;
1104
1105 *is_free = matches;
1106 return 0;
1107}
1108
1109/*
1110 * Compute the number of rtbitmap blocks needed to track the given number of rt
1111 * extents.
1112 */
1113xfs_filblks_t
1114xfs_rtbitmap_blockcount(
1115 struct xfs_mount *mp,
1116 xfs_rtbxlen_t rtextents)
1117{
1118 return howmany_64(rtextents, NBBY * mp->m_sb.sb_blocksize);
1119}
1120
1121/*
1122 * Compute the number of rtbitmap words needed to populate every block of a
1123 * bitmap that is large enough to track the given number of rt extents.
1124 */
1125unsigned long long
1126xfs_rtbitmap_wordcount(
1127 struct xfs_mount *mp,
1128 xfs_rtbxlen_t rtextents)
1129{
1130 xfs_filblks_t blocks;
1131
1132 blocks = xfs_rtbitmap_blockcount(mp, rtextents);
1133 return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
1134}
1135
1136/* Compute the number of rtsummary blocks needed to track the given rt space. */
1137xfs_filblks_t
1138xfs_rtsummary_blockcount(
1139 struct xfs_mount *mp,
1140 unsigned int rsumlevels,
1141 xfs_extlen_t rbmblocks)
1142{
1143 unsigned long long rsumwords;
1144
1145 rsumwords = (unsigned long long)rsumlevels * rbmblocks;
1146 return XFS_B_TO_FSB(mp, rsumwords << XFS_WORDLOG);
1147}
1148
1149/*
1150 * Compute the number of rtsummary info words needed to populate every block of
1151 * a summary file that is large enough to track the given rt space.
1152 */
1153unsigned long long
1154xfs_rtsummary_wordcount(
1155 struct xfs_mount *mp,
1156 unsigned int rsumlevels,
1157 xfs_extlen_t rbmblocks)
1158{
1159 xfs_filblks_t blocks;
1160
1161 blocks = xfs_rtsummary_blockcount(mp, rsumlevels, rbmblocks);
1162 return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
1163}
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_trans.h"
17#include "xfs_rtalloc.h"
18#include "xfs_error.h"
19
20/*
21 * Realtime allocator bitmap functions shared with userspace.
22 */
23
24/*
25 * Real time buffers need verifiers to avoid runtime warnings during IO.
26 * We don't have anything to verify, however, so these are just dummy
27 * operations.
28 */
29static void
30xfs_rtbuf_verify_read(
31 struct xfs_buf *bp)
32{
33 return;
34}
35
36static void
37xfs_rtbuf_verify_write(
38 struct xfs_buf *bp)
39{
40 return;
41}
42
43const struct xfs_buf_ops xfs_rtbuf_ops = {
44 .name = "rtbuf",
45 .verify_read = xfs_rtbuf_verify_read,
46 .verify_write = xfs_rtbuf_verify_write,
47};
48
49/*
50 * Get a buffer for the bitmap or summary file block specified.
51 * The buffer is returned read and locked.
52 */
53int
54xfs_rtbuf_get(
55 xfs_mount_t *mp, /* file system mount structure */
56 xfs_trans_t *tp, /* transaction pointer */
57 xfs_rtblock_t block, /* block number in bitmap or summary */
58 int issum, /* is summary not bitmap */
59 struct xfs_buf **bpp) /* output: buffer for the block */
60{
61 struct xfs_buf *bp; /* block buffer, result */
62 xfs_inode_t *ip; /* bitmap or summary inode */
63 xfs_bmbt_irec_t map;
64 int nmap = 1;
65 int error; /* error value */
66
67 ip = issum ? mp->m_rsumip : mp->m_rbmip;
68
69 error = xfs_bmapi_read(ip, block, 1, &map, &nmap, 0);
70 if (error)
71 return error;
72
73 if (XFS_IS_CORRUPT(mp, nmap == 0 || !xfs_bmap_is_written_extent(&map)))
74 return -EFSCORRUPTED;
75
76 ASSERT(map.br_startblock != NULLFSBLOCK);
77 error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
78 XFS_FSB_TO_DADDR(mp, map.br_startblock),
79 mp->m_bsize, 0, &bp, &xfs_rtbuf_ops);
80 if (error)
81 return error;
82
83 xfs_trans_buf_set_type(tp, bp, issum ? XFS_BLFT_RTSUMMARY_BUF
84 : XFS_BLFT_RTBITMAP_BUF);
85 *bpp = bp;
86 return 0;
87}
88
89/*
90 * Searching backward from start to limit, find the first block whose
91 * allocated/free state is different from start's.
92 */
93int
94xfs_rtfind_back(
95 xfs_mount_t *mp, /* file system mount point */
96 xfs_trans_t *tp, /* transaction pointer */
97 xfs_rtblock_t start, /* starting block to look at */
98 xfs_rtblock_t limit, /* last block to look at */
99 xfs_rtblock_t *rtblock) /* out: start block found */
100{
101 xfs_rtword_t *b; /* current word in buffer */
102 int bit; /* bit number in the word */
103 xfs_rtblock_t block; /* bitmap block number */
104 struct xfs_buf *bp; /* buf for the block */
105 xfs_rtword_t *bufp; /* starting word in buffer */
106 int error; /* error value */
107 xfs_rtblock_t firstbit; /* first useful bit in the word */
108 xfs_rtblock_t i; /* current bit number rel. to start */
109 xfs_rtblock_t len; /* length of inspected area */
110 xfs_rtword_t mask; /* mask of relevant bits for value */
111 xfs_rtword_t want; /* mask for "good" values */
112 xfs_rtword_t wdiff; /* difference from wanted value */
113 int word; /* word number in the buffer */
114
115 /*
116 * Compute and read in starting bitmap block for starting block.
117 */
118 block = XFS_BITTOBLOCK(mp, start);
119 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
120 if (error) {
121 return error;
122 }
123 bufp = bp->b_addr;
124 /*
125 * Get the first word's index & point to it.
126 */
127 word = XFS_BITTOWORD(mp, start);
128 b = &bufp[word];
129 bit = (int)(start & (XFS_NBWORD - 1));
130 len = start - limit + 1;
131 /*
132 * Compute match value, based on the bit at start: if 1 (free)
133 * then all-ones, else all-zeroes.
134 */
135 want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
136 /*
137 * If the starting position is not word-aligned, deal with the
138 * partial word.
139 */
140 if (bit < XFS_NBWORD - 1) {
141 /*
142 * Calculate first (leftmost) bit number to look at,
143 * and mask for all the relevant bits in this word.
144 */
145 firstbit = XFS_RTMAX((xfs_srtblock_t)(bit - len + 1), 0);
146 mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
147 firstbit;
148 /*
149 * Calculate the difference between the value there
150 * and what we're looking for.
151 */
152 if ((wdiff = (*b ^ want) & mask)) {
153 /*
154 * Different. Mark where we are and return.
155 */
156 xfs_trans_brelse(tp, bp);
157 i = bit - XFS_RTHIBIT(wdiff);
158 *rtblock = start - i + 1;
159 return 0;
160 }
161 i = bit - firstbit + 1;
162 /*
163 * Go on to previous block if that's where the previous word is
164 * and we need the previous word.
165 */
166 if (--word == -1 && i < len) {
167 /*
168 * If done with this block, get the previous one.
169 */
170 xfs_trans_brelse(tp, bp);
171 error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
172 if (error) {
173 return error;
174 }
175 bufp = bp->b_addr;
176 word = XFS_BLOCKWMASK(mp);
177 b = &bufp[word];
178 } else {
179 /*
180 * Go on to the previous word in the buffer.
181 */
182 b--;
183 }
184 } else {
185 /*
186 * Starting on a word boundary, no partial word.
187 */
188 i = 0;
189 }
190 /*
191 * Loop over whole words in buffers. When we use up one buffer
192 * we move on to the previous one.
193 */
194 while (len - i >= XFS_NBWORD) {
195 /*
196 * Compute difference between actual and desired value.
197 */
198 if ((wdiff = *b ^ want)) {
199 /*
200 * Different, mark where we are and return.
201 */
202 xfs_trans_brelse(tp, bp);
203 i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
204 *rtblock = start - i + 1;
205 return 0;
206 }
207 i += XFS_NBWORD;
208 /*
209 * Go on to previous block if that's where the previous word is
210 * and we need the previous word.
211 */
212 if (--word == -1 && i < len) {
213 /*
214 * If done with this block, get the previous one.
215 */
216 xfs_trans_brelse(tp, bp);
217 error = xfs_rtbuf_get(mp, tp, --block, 0, &bp);
218 if (error) {
219 return error;
220 }
221 bufp = bp->b_addr;
222 word = XFS_BLOCKWMASK(mp);
223 b = &bufp[word];
224 } else {
225 /*
226 * Go on to the previous word in the buffer.
227 */
228 b--;
229 }
230 }
231 /*
232 * If not ending on a word boundary, deal with the last
233 * (partial) word.
234 */
235 if (len - i) {
236 /*
237 * Calculate first (leftmost) bit number to look at,
238 * and mask for all the relevant bits in this word.
239 */
240 firstbit = XFS_NBWORD - (len - i);
241 mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
242 /*
243 * Compute difference between actual and desired value.
244 */
245 if ((wdiff = (*b ^ want) & mask)) {
246 /*
247 * Different, mark where we are and return.
248 */
249 xfs_trans_brelse(tp, bp);
250 i += XFS_NBWORD - 1 - XFS_RTHIBIT(wdiff);
251 *rtblock = start - i + 1;
252 return 0;
253 } else
254 i = len;
255 }
256 /*
257 * No match, return that we scanned the whole area.
258 */
259 xfs_trans_brelse(tp, bp);
260 *rtblock = start - i + 1;
261 return 0;
262}
263
264/*
265 * Searching forward from start to limit, find the first block whose
266 * allocated/free state is different from start's.
267 */
268int
269xfs_rtfind_forw(
270 xfs_mount_t *mp, /* file system mount point */
271 xfs_trans_t *tp, /* transaction pointer */
272 xfs_rtblock_t start, /* starting block to look at */
273 xfs_rtblock_t limit, /* last block to look at */
274 xfs_rtblock_t *rtblock) /* out: start block found */
275{
276 xfs_rtword_t *b; /* current word in buffer */
277 int bit; /* bit number in the word */
278 xfs_rtblock_t block; /* bitmap block number */
279 struct xfs_buf *bp; /* buf for the block */
280 xfs_rtword_t *bufp; /* starting word in buffer */
281 int error; /* error value */
282 xfs_rtblock_t i; /* current bit number rel. to start */
283 xfs_rtblock_t lastbit; /* last useful bit in the word */
284 xfs_rtblock_t len; /* length of inspected area */
285 xfs_rtword_t mask; /* mask of relevant bits for value */
286 xfs_rtword_t want; /* mask for "good" values */
287 xfs_rtword_t wdiff; /* difference from wanted value */
288 int word; /* word number in the buffer */
289
290 /*
291 * Compute and read in starting bitmap block for starting block.
292 */
293 block = XFS_BITTOBLOCK(mp, start);
294 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
295 if (error) {
296 return error;
297 }
298 bufp = bp->b_addr;
299 /*
300 * Get the first word's index & point to it.
301 */
302 word = XFS_BITTOWORD(mp, start);
303 b = &bufp[word];
304 bit = (int)(start & (XFS_NBWORD - 1));
305 len = limit - start + 1;
306 /*
307 * Compute match value, based on the bit at start: if 1 (free)
308 * then all-ones, else all-zeroes.
309 */
310 want = (*b & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
311 /*
312 * If the starting position is not word-aligned, deal with the
313 * partial word.
314 */
315 if (bit) {
316 /*
317 * Calculate last (rightmost) bit number to look at,
318 * and mask for all the relevant bits in this word.
319 */
320 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
321 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
322 /*
323 * Calculate the difference between the value there
324 * and what we're looking for.
325 */
326 if ((wdiff = (*b ^ want) & mask)) {
327 /*
328 * Different. Mark where we are and return.
329 */
330 xfs_trans_brelse(tp, bp);
331 i = XFS_RTLOBIT(wdiff) - bit;
332 *rtblock = start + i - 1;
333 return 0;
334 }
335 i = lastbit - bit;
336 /*
337 * Go on to next block if that's where the next word is
338 * and we need the next word.
339 */
340 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
341 /*
342 * If done with this block, get the previous one.
343 */
344 xfs_trans_brelse(tp, bp);
345 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
346 if (error) {
347 return error;
348 }
349 b = bufp = bp->b_addr;
350 word = 0;
351 } else {
352 /*
353 * Go on to the previous word in the buffer.
354 */
355 b++;
356 }
357 } else {
358 /*
359 * Starting on a word boundary, no partial word.
360 */
361 i = 0;
362 }
363 /*
364 * Loop over whole words in buffers. When we use up one buffer
365 * we move on to the next one.
366 */
367 while (len - i >= XFS_NBWORD) {
368 /*
369 * Compute difference between actual and desired value.
370 */
371 if ((wdiff = *b ^ want)) {
372 /*
373 * Different, mark where we are and return.
374 */
375 xfs_trans_brelse(tp, bp);
376 i += XFS_RTLOBIT(wdiff);
377 *rtblock = start + i - 1;
378 return 0;
379 }
380 i += XFS_NBWORD;
381 /*
382 * Go on to next block if that's where the next word is
383 * and we need the next word.
384 */
385 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
386 /*
387 * If done with this block, get the next one.
388 */
389 xfs_trans_brelse(tp, bp);
390 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
391 if (error) {
392 return error;
393 }
394 b = bufp = bp->b_addr;
395 word = 0;
396 } else {
397 /*
398 * Go on to the next word in the buffer.
399 */
400 b++;
401 }
402 }
403 /*
404 * If not ending on a word boundary, deal with the last
405 * (partial) word.
406 */
407 if ((lastbit = len - i)) {
408 /*
409 * Calculate mask for all the relevant bits in this word.
410 */
411 mask = ((xfs_rtword_t)1 << lastbit) - 1;
412 /*
413 * Compute difference between actual and desired value.
414 */
415 if ((wdiff = (*b ^ want) & mask)) {
416 /*
417 * Different, mark where we are and return.
418 */
419 xfs_trans_brelse(tp, bp);
420 i += XFS_RTLOBIT(wdiff);
421 *rtblock = start + i - 1;
422 return 0;
423 } else
424 i = len;
425 }
426 /*
427 * No match, return that we scanned the whole area.
428 */
429 xfs_trans_brelse(tp, bp);
430 *rtblock = start + i - 1;
431 return 0;
432}
433
434/*
435 * Read and/or modify the summary information for a given extent size,
436 * bitmap block combination.
437 * Keeps track of a current summary block, so we don't keep reading
438 * it from the buffer cache.
439 *
440 * Summary information is returned in *sum if specified.
441 * If no delta is specified, returns summary only.
442 */
443int
444xfs_rtmodify_summary_int(
445 xfs_mount_t *mp, /* file system mount structure */
446 xfs_trans_t *tp, /* transaction pointer */
447 int log, /* log2 of extent size */
448 xfs_rtblock_t bbno, /* bitmap block number */
449 int delta, /* change to make to summary info */
450 struct xfs_buf **rbpp, /* in/out: summary block buffer */
451 xfs_fsblock_t *rsb, /* in/out: summary block number */
452 xfs_suminfo_t *sum) /* out: summary info for this block */
453{
454 struct xfs_buf *bp; /* buffer for the summary block */
455 int error; /* error value */
456 xfs_fsblock_t sb; /* summary fsblock */
457 int so; /* index into the summary file */
458 xfs_suminfo_t *sp; /* pointer to returned data */
459
460 /*
461 * Compute entry number in the summary file.
462 */
463 so = XFS_SUMOFFS(mp, log, bbno);
464 /*
465 * Compute the block number in the summary file.
466 */
467 sb = XFS_SUMOFFSTOBLOCK(mp, so);
468 /*
469 * If we have an old buffer, and the block number matches, use that.
470 */
471 if (*rbpp && *rsb == sb)
472 bp = *rbpp;
473 /*
474 * Otherwise we have to get the buffer.
475 */
476 else {
477 /*
478 * If there was an old one, get rid of it first.
479 */
480 if (*rbpp)
481 xfs_trans_brelse(tp, *rbpp);
482 error = xfs_rtbuf_get(mp, tp, sb, 1, &bp);
483 if (error) {
484 return error;
485 }
486 /*
487 * Remember this buffer and block for the next call.
488 */
489 *rbpp = bp;
490 *rsb = sb;
491 }
492 /*
493 * Point to the summary information, modify/log it, and/or copy it out.
494 */
495 sp = XFS_SUMPTR(mp, bp, so);
496 if (delta) {
497 uint first = (uint)((char *)sp - (char *)bp->b_addr);
498
499 *sp += delta;
500 if (mp->m_rsum_cache) {
501 if (*sp == 0 && log == mp->m_rsum_cache[bbno])
502 mp->m_rsum_cache[bbno]++;
503 if (*sp != 0 && log < mp->m_rsum_cache[bbno])
504 mp->m_rsum_cache[bbno] = log;
505 }
506 xfs_trans_log_buf(tp, bp, first, first + sizeof(*sp) - 1);
507 }
508 if (sum)
509 *sum = *sp;
510 return 0;
511}
512
513int
514xfs_rtmodify_summary(
515 xfs_mount_t *mp, /* file system mount structure */
516 xfs_trans_t *tp, /* transaction pointer */
517 int log, /* log2 of extent size */
518 xfs_rtblock_t bbno, /* bitmap block number */
519 int delta, /* change to make to summary info */
520 struct xfs_buf **rbpp, /* in/out: summary block buffer */
521 xfs_fsblock_t *rsb) /* in/out: summary block number */
522{
523 return xfs_rtmodify_summary_int(mp, tp, log, bbno,
524 delta, rbpp, rsb, NULL);
525}
526
527/*
528 * Set the given range of bitmap bits to the given value.
529 * Do whatever I/O and logging is required.
530 */
531int
532xfs_rtmodify_range(
533 xfs_mount_t *mp, /* file system mount point */
534 xfs_trans_t *tp, /* transaction pointer */
535 xfs_rtblock_t start, /* starting block to modify */
536 xfs_extlen_t len, /* length of extent to modify */
537 int val) /* 1 for free, 0 for allocated */
538{
539 xfs_rtword_t *b; /* current word in buffer */
540 int bit; /* bit number in the word */
541 xfs_rtblock_t block; /* bitmap block number */
542 struct xfs_buf *bp; /* buf for the block */
543 xfs_rtword_t *bufp; /* starting word in buffer */
544 int error; /* error value */
545 xfs_rtword_t *first; /* first used word in the buffer */
546 int i; /* current bit number rel. to start */
547 int lastbit; /* last useful bit in word */
548 xfs_rtword_t mask; /* mask o frelevant bits for value */
549 int word; /* word number in the buffer */
550
551 /*
552 * Compute starting bitmap block number.
553 */
554 block = XFS_BITTOBLOCK(mp, start);
555 /*
556 * Read the bitmap block, and point to its data.
557 */
558 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
559 if (error) {
560 return error;
561 }
562 bufp = bp->b_addr;
563 /*
564 * Compute the starting word's address, and starting bit.
565 */
566 word = XFS_BITTOWORD(mp, start);
567 first = b = &bufp[word];
568 bit = (int)(start & (XFS_NBWORD - 1));
569 /*
570 * 0 (allocated) => all zeroes; 1 (free) => all ones.
571 */
572 val = -val;
573 /*
574 * If not starting on a word boundary, deal with the first
575 * (partial) word.
576 */
577 if (bit) {
578 /*
579 * Compute first bit not changed and mask of relevant bits.
580 */
581 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
582 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
583 /*
584 * Set/clear the active bits.
585 */
586 if (val)
587 *b |= mask;
588 else
589 *b &= ~mask;
590 i = lastbit - bit;
591 /*
592 * Go on to the next block if that's where the next word is
593 * and we need the next word.
594 */
595 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
596 /*
597 * Log the changed part of this block.
598 * Get the next one.
599 */
600 xfs_trans_log_buf(tp, bp,
601 (uint)((char *)first - (char *)bufp),
602 (uint)((char *)b - (char *)bufp));
603 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
604 if (error) {
605 return error;
606 }
607 first = b = bufp = bp->b_addr;
608 word = 0;
609 } else {
610 /*
611 * Go on to the next word in the buffer
612 */
613 b++;
614 }
615 } else {
616 /*
617 * Starting on a word boundary, no partial word.
618 */
619 i = 0;
620 }
621 /*
622 * Loop over whole words in buffers. When we use up one buffer
623 * we move on to the next one.
624 */
625 while (len - i >= XFS_NBWORD) {
626 /*
627 * Set the word value correctly.
628 */
629 *b = val;
630 i += XFS_NBWORD;
631 /*
632 * Go on to the next block if that's where the next word is
633 * and we need the next word.
634 */
635 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
636 /*
637 * Log the changed part of this block.
638 * Get the next one.
639 */
640 xfs_trans_log_buf(tp, bp,
641 (uint)((char *)first - (char *)bufp),
642 (uint)((char *)b - (char *)bufp));
643 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
644 if (error) {
645 return error;
646 }
647 first = b = bufp = bp->b_addr;
648 word = 0;
649 } else {
650 /*
651 * Go on to the next word in the buffer
652 */
653 b++;
654 }
655 }
656 /*
657 * If not ending on a word boundary, deal with the last
658 * (partial) word.
659 */
660 if ((lastbit = len - i)) {
661 /*
662 * Compute a mask of relevant bits.
663 */
664 mask = ((xfs_rtword_t)1 << lastbit) - 1;
665 /*
666 * Set/clear the active bits.
667 */
668 if (val)
669 *b |= mask;
670 else
671 *b &= ~mask;
672 b++;
673 }
674 /*
675 * Log any remaining changed bytes.
676 */
677 if (b > first)
678 xfs_trans_log_buf(tp, bp, (uint)((char *)first - (char *)bufp),
679 (uint)((char *)b - (char *)bufp - 1));
680 return 0;
681}
682
683/*
684 * Mark an extent specified by start and len freed.
685 * Updates all the summary information as well as the bitmap.
686 */
687int
688xfs_rtfree_range(
689 xfs_mount_t *mp, /* file system mount point */
690 xfs_trans_t *tp, /* transaction pointer */
691 xfs_rtblock_t start, /* starting block to free */
692 xfs_extlen_t len, /* length to free */
693 struct xfs_buf **rbpp, /* in/out: summary block buffer */
694 xfs_fsblock_t *rsb) /* in/out: summary block number */
695{
696 xfs_rtblock_t end; /* end of the freed extent */
697 int error; /* error value */
698 xfs_rtblock_t postblock; /* first block freed > end */
699 xfs_rtblock_t preblock; /* first block freed < start */
700
701 end = start + len - 1;
702 /*
703 * Modify the bitmap to mark this extent freed.
704 */
705 error = xfs_rtmodify_range(mp, tp, start, len, 1);
706 if (error) {
707 return error;
708 }
709 /*
710 * Assume we're freeing out of the middle of an allocated extent.
711 * We need to find the beginning and end of the extent so we can
712 * properly update the summary.
713 */
714 error = xfs_rtfind_back(mp, tp, start, 0, &preblock);
715 if (error) {
716 return error;
717 }
718 /*
719 * Find the next allocated block (end of allocated extent).
720 */
721 error = xfs_rtfind_forw(mp, tp, end, mp->m_sb.sb_rextents - 1,
722 &postblock);
723 if (error)
724 return error;
725 /*
726 * If there are blocks not being freed at the front of the
727 * old extent, add summary data for them to be allocated.
728 */
729 if (preblock < start) {
730 error = xfs_rtmodify_summary(mp, tp,
731 XFS_RTBLOCKLOG(start - preblock),
732 XFS_BITTOBLOCK(mp, preblock), -1, rbpp, rsb);
733 if (error) {
734 return error;
735 }
736 }
737 /*
738 * If there are blocks not being freed at the end of the
739 * old extent, add summary data for them to be allocated.
740 */
741 if (postblock > end) {
742 error = xfs_rtmodify_summary(mp, tp,
743 XFS_RTBLOCKLOG(postblock - end),
744 XFS_BITTOBLOCK(mp, end + 1), -1, rbpp, rsb);
745 if (error) {
746 return error;
747 }
748 }
749 /*
750 * Increment the summary information corresponding to the entire
751 * (new) free extent.
752 */
753 error = xfs_rtmodify_summary(mp, tp,
754 XFS_RTBLOCKLOG(postblock + 1 - preblock),
755 XFS_BITTOBLOCK(mp, preblock), 1, rbpp, rsb);
756 return error;
757}
758
759/*
760 * Check that the given range is either all allocated (val = 0) or
761 * all free (val = 1).
762 */
763int
764xfs_rtcheck_range(
765 xfs_mount_t *mp, /* file system mount point */
766 xfs_trans_t *tp, /* transaction pointer */
767 xfs_rtblock_t start, /* starting block number of extent */
768 xfs_extlen_t len, /* length of extent */
769 int val, /* 1 for free, 0 for allocated */
770 xfs_rtblock_t *new, /* out: first block not matching */
771 int *stat) /* out: 1 for matches, 0 for not */
772{
773 xfs_rtword_t *b; /* current word in buffer */
774 int bit; /* bit number in the word */
775 xfs_rtblock_t block; /* bitmap block number */
776 struct xfs_buf *bp; /* buf for the block */
777 xfs_rtword_t *bufp; /* starting word in buffer */
778 int error; /* error value */
779 xfs_rtblock_t i; /* current bit number rel. to start */
780 xfs_rtblock_t lastbit; /* last useful bit in word */
781 xfs_rtword_t mask; /* mask of relevant bits for value */
782 xfs_rtword_t wdiff; /* difference from wanted value */
783 int word; /* word number in the buffer */
784
785 /*
786 * Compute starting bitmap block number
787 */
788 block = XFS_BITTOBLOCK(mp, start);
789 /*
790 * Read the bitmap block.
791 */
792 error = xfs_rtbuf_get(mp, tp, block, 0, &bp);
793 if (error) {
794 return error;
795 }
796 bufp = bp->b_addr;
797 /*
798 * Compute the starting word's address, and starting bit.
799 */
800 word = XFS_BITTOWORD(mp, start);
801 b = &bufp[word];
802 bit = (int)(start & (XFS_NBWORD - 1));
803 /*
804 * 0 (allocated) => all zero's; 1 (free) => all one's.
805 */
806 val = -val;
807 /*
808 * If not starting on a word boundary, deal with the first
809 * (partial) word.
810 */
811 if (bit) {
812 /*
813 * Compute first bit not examined.
814 */
815 lastbit = XFS_RTMIN(bit + len, XFS_NBWORD);
816 /*
817 * Mask of relevant bits.
818 */
819 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
820 /*
821 * Compute difference between actual and desired value.
822 */
823 if ((wdiff = (*b ^ val) & mask)) {
824 /*
825 * Different, compute first wrong bit and return.
826 */
827 xfs_trans_brelse(tp, bp);
828 i = XFS_RTLOBIT(wdiff) - bit;
829 *new = start + i;
830 *stat = 0;
831 return 0;
832 }
833 i = lastbit - bit;
834 /*
835 * Go on to next block if that's where the next word is
836 * and we need the next word.
837 */
838 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
839 /*
840 * If done with this block, get the next one.
841 */
842 xfs_trans_brelse(tp, bp);
843 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
844 if (error) {
845 return error;
846 }
847 b = bufp = bp->b_addr;
848 word = 0;
849 } else {
850 /*
851 * Go on to the next word in the buffer.
852 */
853 b++;
854 }
855 } else {
856 /*
857 * Starting on a word boundary, no partial word.
858 */
859 i = 0;
860 }
861 /*
862 * Loop over whole words in buffers. When we use up one buffer
863 * we move on to the next one.
864 */
865 while (len - i >= XFS_NBWORD) {
866 /*
867 * Compute difference between actual and desired value.
868 */
869 if ((wdiff = *b ^ val)) {
870 /*
871 * Different, compute first wrong bit and return.
872 */
873 xfs_trans_brelse(tp, bp);
874 i += XFS_RTLOBIT(wdiff);
875 *new = start + i;
876 *stat = 0;
877 return 0;
878 }
879 i += XFS_NBWORD;
880 /*
881 * Go on to next block if that's where the next word is
882 * and we need the next word.
883 */
884 if (++word == XFS_BLOCKWSIZE(mp) && i < len) {
885 /*
886 * If done with this block, get the next one.
887 */
888 xfs_trans_brelse(tp, bp);
889 error = xfs_rtbuf_get(mp, tp, ++block, 0, &bp);
890 if (error) {
891 return error;
892 }
893 b = bufp = bp->b_addr;
894 word = 0;
895 } else {
896 /*
897 * Go on to the next word in the buffer.
898 */
899 b++;
900 }
901 }
902 /*
903 * If not ending on a word boundary, deal with the last
904 * (partial) word.
905 */
906 if ((lastbit = len - i)) {
907 /*
908 * Mask of relevant bits.
909 */
910 mask = ((xfs_rtword_t)1 << lastbit) - 1;
911 /*
912 * Compute difference between actual and desired value.
913 */
914 if ((wdiff = (*b ^ val) & mask)) {
915 /*
916 * Different, compute first wrong bit and return.
917 */
918 xfs_trans_brelse(tp, bp);
919 i += XFS_RTLOBIT(wdiff);
920 *new = start + i;
921 *stat = 0;
922 return 0;
923 } else
924 i = len;
925 }
926 /*
927 * Successful, return.
928 */
929 xfs_trans_brelse(tp, bp);
930 *new = start + i;
931 *stat = 1;
932 return 0;
933}
934
935#ifdef DEBUG
936/*
937 * Check that the given extent (block range) is allocated already.
938 */
939STATIC int /* error */
940xfs_rtcheck_alloc_range(
941 xfs_mount_t *mp, /* file system mount point */
942 xfs_trans_t *tp, /* transaction pointer */
943 xfs_rtblock_t bno, /* starting block number of extent */
944 xfs_extlen_t len) /* length of extent */
945{
946 xfs_rtblock_t new; /* dummy for xfs_rtcheck_range */
947 int stat;
948 int error;
949
950 error = xfs_rtcheck_range(mp, tp, bno, len, 0, &new, &stat);
951 if (error)
952 return error;
953 ASSERT(stat);
954 return 0;
955}
956#else
957#define xfs_rtcheck_alloc_range(m,t,b,l) (0)
958#endif
959/*
960 * Free an extent in the realtime subvolume. Length is expressed in
961 * realtime extents, as is the block number.
962 */
963int /* error */
964xfs_rtfree_extent(
965 xfs_trans_t *tp, /* transaction pointer */
966 xfs_rtblock_t bno, /* starting block number to free */
967 xfs_extlen_t len) /* length of extent freed */
968{
969 int error; /* error value */
970 xfs_mount_t *mp; /* file system mount structure */
971 xfs_fsblock_t sb; /* summary file block number */
972 struct xfs_buf *sumbp = NULL; /* summary file block buffer */
973
974 mp = tp->t_mountp;
975
976 ASSERT(mp->m_rbmip->i_itemp != NULL);
977 ASSERT(xfs_isilocked(mp->m_rbmip, XFS_ILOCK_EXCL));
978
979 error = xfs_rtcheck_alloc_range(mp, tp, bno, len);
980 if (error)
981 return error;
982
983 /*
984 * Free the range of realtime blocks.
985 */
986 error = xfs_rtfree_range(mp, tp, bno, len, &sumbp, &sb);
987 if (error) {
988 return error;
989 }
990 /*
991 * Mark more blocks free in the superblock.
992 */
993 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
994 /*
995 * If we've now freed all the blocks, reset the file sequence
996 * number to 0.
997 */
998 if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
999 mp->m_sb.sb_rextents) {
1000 if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM))
1001 mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
1002 *(uint64_t *)&VFS_I(mp->m_rbmip)->i_atime = 0;
1003 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
1004 }
1005 return 0;
1006}
1007
1008/* Find all the free records within a given range. */
1009int
1010xfs_rtalloc_query_range(
1011 struct xfs_trans *tp,
1012 struct xfs_rtalloc_rec *low_rec,
1013 struct xfs_rtalloc_rec *high_rec,
1014 xfs_rtalloc_query_range_fn fn,
1015 void *priv)
1016{
1017 struct xfs_rtalloc_rec rec;
1018 struct xfs_mount *mp = tp->t_mountp;
1019 xfs_rtblock_t rtstart;
1020 xfs_rtblock_t rtend;
1021 int is_free;
1022 int error = 0;
1023
1024 if (low_rec->ar_startext > high_rec->ar_startext)
1025 return -EINVAL;
1026 if (low_rec->ar_startext >= mp->m_sb.sb_rextents ||
1027 low_rec->ar_startext == high_rec->ar_startext)
1028 return 0;
1029 high_rec->ar_startext = min(high_rec->ar_startext,
1030 mp->m_sb.sb_rextents - 1);
1031
1032 /* Iterate the bitmap, looking for discrepancies. */
1033 rtstart = low_rec->ar_startext;
1034 while (rtstart <= high_rec->ar_startext) {
1035 /* Is the first block free? */
1036 error = xfs_rtcheck_range(mp, tp, rtstart, 1, 1, &rtend,
1037 &is_free);
1038 if (error)
1039 break;
1040
1041 /* How long does the extent go for? */
1042 error = xfs_rtfind_forw(mp, tp, rtstart,
1043 high_rec->ar_startext, &rtend);
1044 if (error)
1045 break;
1046
1047 if (is_free) {
1048 rec.ar_startext = rtstart;
1049 rec.ar_extcount = rtend - rtstart + 1;
1050
1051 error = fn(tp, &rec, priv);
1052 if (error)
1053 break;
1054 }
1055
1056 rtstart = rtend + 1;
1057 }
1058
1059 return error;
1060}
1061
1062/* Find all the free records. */
1063int
1064xfs_rtalloc_query_all(
1065 struct xfs_trans *tp,
1066 xfs_rtalloc_query_range_fn fn,
1067 void *priv)
1068{
1069 struct xfs_rtalloc_rec keys[2];
1070
1071 keys[0].ar_startext = 0;
1072 keys[1].ar_startext = tp->t_mountp->m_sb.sb_rextents - 1;
1073 keys[0].ar_extcount = keys[1].ar_extcount = 0;
1074
1075 return xfs_rtalloc_query_range(tp, &keys[0], &keys[1], fn, priv);
1076}
1077
1078/* Is the given extent all free? */
1079int
1080xfs_rtalloc_extent_is_free(
1081 struct xfs_mount *mp,
1082 struct xfs_trans *tp,
1083 xfs_rtblock_t start,
1084 xfs_extlen_t len,
1085 bool *is_free)
1086{
1087 xfs_rtblock_t end;
1088 int matches;
1089 int error;
1090
1091 error = xfs_rtcheck_range(mp, tp, start, len, 1, &end, &matches);
1092 if (error)
1093 return error;
1094
1095 *is_free = matches;
1096 return 0;
1097}