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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}