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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#include "xfs_health.h"
21
22/*
23 * Realtime allocator bitmap functions shared with userspace.
24 */
25
26/*
27 * Real time buffers need verifiers to avoid runtime warnings during IO.
28 * We don't have anything to verify, however, so these are just dummy
29 * operations.
30 */
31static void
32xfs_rtbuf_verify_read(
33 struct xfs_buf *bp)
34{
35 return;
36}
37
38static void
39xfs_rtbuf_verify_write(
40 struct xfs_buf *bp)
41{
42 return;
43}
44
45const struct xfs_buf_ops xfs_rtbuf_ops = {
46 .name = "rtbuf",
47 .verify_read = xfs_rtbuf_verify_read,
48 .verify_write = xfs_rtbuf_verify_write,
49};
50
51/* Release cached rt bitmap and summary buffers. */
52void
53xfs_rtbuf_cache_relse(
54 struct xfs_rtalloc_args *args)
55{
56 if (args->rbmbp) {
57 xfs_trans_brelse(args->tp, args->rbmbp);
58 args->rbmbp = NULL;
59 args->rbmoff = NULLFILEOFF;
60 }
61 if (args->sumbp) {
62 xfs_trans_brelse(args->tp, args->sumbp);
63 args->sumbp = NULL;
64 args->sumoff = NULLFILEOFF;
65 }
66}
67
68/*
69 * Get a buffer for the bitmap or summary file block specified.
70 * The buffer is returned read and locked.
71 */
72int
73xfs_rtbuf_get(
74 struct xfs_rtalloc_args *args,
75 xfs_fileoff_t block, /* block number in bitmap or summary */
76 int issum) /* is summary not bitmap */
77{
78 struct xfs_mount *mp = args->mp;
79 struct xfs_buf **cbpp; /* cached block buffer */
80 xfs_fileoff_t *coffp; /* cached block number */
81 struct xfs_buf *bp; /* block buffer, result */
82 struct xfs_inode *ip; /* bitmap or summary inode */
83 struct xfs_bmbt_irec map;
84 enum xfs_blft type;
85 int nmap = 1;
86 int error;
87
88 if (issum) {
89 cbpp = &args->sumbp;
90 coffp = &args->sumoff;
91 ip = mp->m_rsumip;
92 type = XFS_BLFT_RTSUMMARY_BUF;
93 } else {
94 cbpp = &args->rbmbp;
95 coffp = &args->rbmoff;
96 ip = mp->m_rbmip;
97 type = XFS_BLFT_RTBITMAP_BUF;
98 }
99
100 /*
101 * If we have a cached buffer, and the block number matches, use that.
102 */
103 if (*cbpp && *coffp == block)
104 return 0;
105
106 /*
107 * Otherwise we have to have to get the buffer. If there was an old
108 * one, get rid of it first.
109 */
110 if (*cbpp) {
111 xfs_trans_brelse(args->tp, *cbpp);
112 *cbpp = NULL;
113 }
114
115 error = xfs_bmapi_read(ip, block, 1, &map, &nmap, 0);
116 if (error)
117 return error;
118
119 if (XFS_IS_CORRUPT(mp, nmap == 0 || !xfs_bmap_is_written_extent(&map))) {
120 xfs_rt_mark_sick(mp, issum ? XFS_SICK_RT_SUMMARY :
121 XFS_SICK_RT_BITMAP);
122 return -EFSCORRUPTED;
123 }
124
125 ASSERT(map.br_startblock != NULLFSBLOCK);
126 error = xfs_trans_read_buf(mp, args->tp, mp->m_ddev_targp,
127 XFS_FSB_TO_DADDR(mp, map.br_startblock),
128 mp->m_bsize, 0, &bp, &xfs_rtbuf_ops);
129 if (xfs_metadata_is_sick(error))
130 xfs_rt_mark_sick(mp, issum ? XFS_SICK_RT_SUMMARY :
131 XFS_SICK_RT_BITMAP);
132 if (error)
133 return error;
134
135 xfs_trans_buf_set_type(args->tp, bp, type);
136 *cbpp = bp;
137 *coffp = block;
138 return 0;
139}
140
141/*
142 * Searching backward from start to limit, find the first block whose
143 * allocated/free state is different from start's.
144 */
145int
146xfs_rtfind_back(
147 struct xfs_rtalloc_args *args,
148 xfs_rtxnum_t start, /* starting rtext to look at */
149 xfs_rtxnum_t limit, /* last rtext to look at */
150 xfs_rtxnum_t *rtx) /* out: start rtext found */
151{
152 struct xfs_mount *mp = args->mp;
153 int bit; /* bit number in the word */
154 xfs_fileoff_t block; /* bitmap block number */
155 int error; /* error value */
156 xfs_rtxnum_t firstbit; /* first useful bit in the word */
157 xfs_rtxnum_t i; /* current bit number rel. to start */
158 xfs_rtxnum_t len; /* length of inspected area */
159 xfs_rtword_t mask; /* mask of relevant bits for value */
160 xfs_rtword_t want; /* mask for "good" values */
161 xfs_rtword_t wdiff; /* difference from wanted value */
162 xfs_rtword_t incore;
163 unsigned int word; /* word number in the buffer */
164
165 /*
166 * Compute and read in starting bitmap block for starting block.
167 */
168 block = xfs_rtx_to_rbmblock(mp, start);
169 error = xfs_rtbitmap_read_buf(args, block);
170 if (error)
171 return error;
172
173 /*
174 * Get the first word's index & point to it.
175 */
176 word = xfs_rtx_to_rbmword(mp, start);
177 bit = (int)(start & (XFS_NBWORD - 1));
178 len = start - limit + 1;
179 /*
180 * Compute match value, based on the bit at start: if 1 (free)
181 * then all-ones, else all-zeroes.
182 */
183 incore = xfs_rtbitmap_getword(args, word);
184 want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
185 /*
186 * If the starting position is not word-aligned, deal with the
187 * partial word.
188 */
189 if (bit < XFS_NBWORD - 1) {
190 /*
191 * Calculate first (leftmost) bit number to look at,
192 * and mask for all the relevant bits in this word.
193 */
194 firstbit = max_t(xfs_srtblock_t, bit - len + 1, 0);
195 mask = (((xfs_rtword_t)1 << (bit - firstbit + 1)) - 1) <<
196 firstbit;
197 /*
198 * Calculate the difference between the value there
199 * and what we're looking for.
200 */
201 if ((wdiff = (incore ^ want) & mask)) {
202 /*
203 * Different. Mark where we are and return.
204 */
205 i = bit - xfs_highbit32(wdiff);
206 *rtx = start - i + 1;
207 return 0;
208 }
209 i = bit - firstbit + 1;
210 /*
211 * Go on to previous block if that's where the previous word is
212 * and we need the previous word.
213 */
214 if (--word == -1 && i < len) {
215 /*
216 * If done with this block, get the previous one.
217 */
218 error = xfs_rtbitmap_read_buf(args, --block);
219 if (error)
220 return error;
221
222 word = mp->m_blockwsize - 1;
223 }
224 } else {
225 /*
226 * Starting on a word boundary, no partial word.
227 */
228 i = 0;
229 }
230 /*
231 * Loop over whole words in buffers. When we use up one buffer
232 * we move on to the previous one.
233 */
234 while (len - i >= XFS_NBWORD) {
235 /*
236 * Compute difference between actual and desired value.
237 */
238 incore = xfs_rtbitmap_getword(args, word);
239 if ((wdiff = incore ^ want)) {
240 /*
241 * Different, mark where we are and return.
242 */
243 i += XFS_NBWORD - 1 - xfs_highbit32(wdiff);
244 *rtx = start - i + 1;
245 return 0;
246 }
247 i += XFS_NBWORD;
248 /*
249 * Go on to previous block if that's where the previous word is
250 * and we need the previous word.
251 */
252 if (--word == -1 && i < len) {
253 /*
254 * If done with this block, get the previous one.
255 */
256 error = xfs_rtbitmap_read_buf(args, --block);
257 if (error)
258 return error;
259
260 word = mp->m_blockwsize - 1;
261 }
262 }
263 /*
264 * If not ending on a word boundary, deal with the last
265 * (partial) word.
266 */
267 if (len - i) {
268 /*
269 * Calculate first (leftmost) bit number to look at,
270 * and mask for all the relevant bits in this word.
271 */
272 firstbit = XFS_NBWORD - (len - i);
273 mask = (((xfs_rtword_t)1 << (len - i)) - 1) << firstbit;
274 /*
275 * Compute difference between actual and desired value.
276 */
277 incore = xfs_rtbitmap_getword(args, word);
278 if ((wdiff = (incore ^ want) & mask)) {
279 /*
280 * Different, mark where we are and return.
281 */
282 i += XFS_NBWORD - 1 - xfs_highbit32(wdiff);
283 *rtx = start - i + 1;
284 return 0;
285 } else
286 i = len;
287 }
288 /*
289 * No match, return that we scanned the whole area.
290 */
291 *rtx = start - i + 1;
292 return 0;
293}
294
295/*
296 * Searching forward from start to limit, find the first block whose
297 * allocated/free state is different from start's.
298 */
299int
300xfs_rtfind_forw(
301 struct xfs_rtalloc_args *args,
302 xfs_rtxnum_t start, /* starting rtext to look at */
303 xfs_rtxnum_t limit, /* last rtext to look at */
304 xfs_rtxnum_t *rtx) /* out: start rtext found */
305{
306 struct xfs_mount *mp = args->mp;
307 int bit; /* bit number in the word */
308 xfs_fileoff_t block; /* bitmap block number */
309 int error;
310 xfs_rtxnum_t i; /* current bit number rel. to start */
311 xfs_rtxnum_t lastbit;/* last useful bit in the word */
312 xfs_rtxnum_t len; /* length of inspected area */
313 xfs_rtword_t mask; /* mask of relevant bits for value */
314 xfs_rtword_t want; /* mask for "good" values */
315 xfs_rtword_t wdiff; /* difference from wanted value */
316 xfs_rtword_t incore;
317 unsigned int word; /* word number in the buffer */
318
319 /*
320 * Compute and read in starting bitmap block for starting block.
321 */
322 block = xfs_rtx_to_rbmblock(mp, start);
323 error = xfs_rtbitmap_read_buf(args, block);
324 if (error)
325 return error;
326
327 /*
328 * Get the first word's index & point to it.
329 */
330 word = xfs_rtx_to_rbmword(mp, start);
331 bit = (int)(start & (XFS_NBWORD - 1));
332 len = limit - start + 1;
333 /*
334 * Compute match value, based on the bit at start: if 1 (free)
335 * then all-ones, else all-zeroes.
336 */
337 incore = xfs_rtbitmap_getword(args, word);
338 want = (incore & ((xfs_rtword_t)1 << bit)) ? -1 : 0;
339 /*
340 * If the starting position is not word-aligned, deal with the
341 * partial word.
342 */
343 if (bit) {
344 /*
345 * Calculate last (rightmost) bit number to look at,
346 * and mask for all the relevant bits in this word.
347 */
348 lastbit = min(bit + len, XFS_NBWORD);
349 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
350 /*
351 * Calculate the difference between the value there
352 * and what we're looking for.
353 */
354 if ((wdiff = (incore ^ want) & mask)) {
355 /*
356 * Different. Mark where we are and return.
357 */
358 i = xfs_lowbit32(wdiff) - bit;
359 *rtx = start + i - 1;
360 return 0;
361 }
362 i = lastbit - bit;
363 /*
364 * Go on to next block if that's where the next word is
365 * and we need the next word.
366 */
367 if (++word == mp->m_blockwsize && i < len) {
368 /*
369 * If done with this block, get the previous one.
370 */
371 error = xfs_rtbitmap_read_buf(args, ++block);
372 if (error)
373 return error;
374
375 word = 0;
376 }
377 } else {
378 /*
379 * Starting on a word boundary, no partial word.
380 */
381 i = 0;
382 }
383 /*
384 * Loop over whole words in buffers. When we use up one buffer
385 * we move on to the next one.
386 */
387 while (len - i >= XFS_NBWORD) {
388 /*
389 * Compute difference between actual and desired value.
390 */
391 incore = xfs_rtbitmap_getword(args, word);
392 if ((wdiff = incore ^ want)) {
393 /*
394 * Different, mark where we are and return.
395 */
396 i += xfs_lowbit32(wdiff);
397 *rtx = start + i - 1;
398 return 0;
399 }
400 i += XFS_NBWORD;
401 /*
402 * Go on to next block if that's where the next word is
403 * and we need the next word.
404 */
405 if (++word == mp->m_blockwsize && i < len) {
406 /*
407 * If done with this block, get the next one.
408 */
409 error = xfs_rtbitmap_read_buf(args, ++block);
410 if (error)
411 return error;
412
413 word = 0;
414 }
415 }
416 /*
417 * If not ending on a word boundary, deal with the last
418 * (partial) word.
419 */
420 if ((lastbit = len - i)) {
421 /*
422 * Calculate mask for all the relevant bits in this word.
423 */
424 mask = ((xfs_rtword_t)1 << lastbit) - 1;
425 /*
426 * Compute difference between actual and desired value.
427 */
428 incore = xfs_rtbitmap_getword(args, word);
429 if ((wdiff = (incore ^ want) & mask)) {
430 /*
431 * Different, mark where we are and return.
432 */
433 i += xfs_lowbit32(wdiff);
434 *rtx = start + i - 1;
435 return 0;
436 } else
437 i = len;
438 }
439 /*
440 * No match, return that we scanned the whole area.
441 */
442 *rtx = start + i - 1;
443 return 0;
444}
445
446/* Log rtsummary counter at @infoword. */
447static inline void
448xfs_trans_log_rtsummary(
449 struct xfs_rtalloc_args *args,
450 unsigned int infoword)
451{
452 struct xfs_buf *bp = args->sumbp;
453 size_t first, last;
454
455 first = (void *)xfs_rsumblock_infoptr(args, infoword) - bp->b_addr;
456 last = first + sizeof(xfs_suminfo_t) - 1;
457
458 xfs_trans_log_buf(args->tp, bp, first, last);
459}
460
461/*
462 * Modify the summary information for a given extent size, bitmap block
463 * combination.
464 */
465int
466xfs_rtmodify_summary(
467 struct xfs_rtalloc_args *args,
468 int log, /* log2 of extent size */
469 xfs_fileoff_t bbno, /* bitmap block number */
470 int delta) /* in/out: summary block number */
471{
472 struct xfs_mount *mp = args->mp;
473 xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
474 unsigned int infoword;
475 xfs_suminfo_t val;
476 int error;
477
478 error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
479 if (error)
480 return error;
481
482 infoword = xfs_rtsumoffs_to_infoword(mp, so);
483 val = xfs_suminfo_add(args, infoword, delta);
484
485 if (mp->m_rsum_cache) {
486 if (val == 0 && log + 1 == mp->m_rsum_cache[bbno])
487 mp->m_rsum_cache[bbno] = log;
488 if (val != 0 && log >= mp->m_rsum_cache[bbno])
489 mp->m_rsum_cache[bbno] = log + 1;
490 }
491
492 xfs_trans_log_rtsummary(args, infoword);
493 return 0;
494}
495
496/*
497 * Read and return the summary information for a given extent size, bitmap block
498 * combination.
499 */
500int
501xfs_rtget_summary(
502 struct xfs_rtalloc_args *args,
503 int log, /* log2 of extent size */
504 xfs_fileoff_t bbno, /* bitmap block number */
505 xfs_suminfo_t *sum) /* out: summary info for this block */
506{
507 struct xfs_mount *mp = args->mp;
508 xfs_rtsumoff_t so = xfs_rtsumoffs(mp, log, bbno);
509 int error;
510
511 error = xfs_rtsummary_read_buf(args, xfs_rtsumoffs_to_block(mp, so));
512 if (!error)
513 *sum = xfs_suminfo_get(args, xfs_rtsumoffs_to_infoword(mp, so));
514 return error;
515}
516
517/* Log rtbitmap block from the word @from to the byte before @next. */
518static inline void
519xfs_trans_log_rtbitmap(
520 struct xfs_rtalloc_args *args,
521 unsigned int from,
522 unsigned int next)
523{
524 struct xfs_buf *bp = args->rbmbp;
525 size_t first, last;
526
527 first = (void *)xfs_rbmblock_wordptr(args, from) - bp->b_addr;
528 last = ((void *)xfs_rbmblock_wordptr(args, next) - 1) - bp->b_addr;
529
530 xfs_trans_log_buf(args->tp, bp, first, last);
531}
532
533/*
534 * Set the given range of bitmap bits to the given value.
535 * Do whatever I/O and logging is required.
536 */
537int
538xfs_rtmodify_range(
539 struct xfs_rtalloc_args *args,
540 xfs_rtxnum_t start, /* starting rtext to modify */
541 xfs_rtxlen_t len, /* length of extent to modify */
542 int val) /* 1 for free, 0 for allocated */
543{
544 struct xfs_mount *mp = args->mp;
545 int bit; /* bit number in the word */
546 xfs_fileoff_t block; /* bitmap block number */
547 int error;
548 int i; /* current bit number rel. to start */
549 int lastbit; /* last useful bit in word */
550 xfs_rtword_t mask; /* mask of relevant bits for value */
551 xfs_rtword_t incore;
552 unsigned int firstword; /* first word used in the buffer */
553 unsigned int word; /* word number in the buffer */
554
555 /*
556 * Compute starting bitmap block number.
557 */
558 block = xfs_rtx_to_rbmblock(mp, start);
559 /*
560 * Read the bitmap block, and point to its data.
561 */
562 error = xfs_rtbitmap_read_buf(args, block);
563 if (error)
564 return error;
565
566 /*
567 * Compute the starting word's address, and starting bit.
568 */
569 firstword = word = xfs_rtx_to_rbmword(mp, start);
570 bit = (int)(start & (XFS_NBWORD - 1));
571 /*
572 * 0 (allocated) => all zeroes; 1 (free) => all ones.
573 */
574 val = -val;
575 /*
576 * If not starting on a word boundary, deal with the first
577 * (partial) word.
578 */
579 if (bit) {
580 /*
581 * Compute first bit not changed and mask of relevant bits.
582 */
583 lastbit = min(bit + len, XFS_NBWORD);
584 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
585 /*
586 * Set/clear the active bits.
587 */
588 incore = xfs_rtbitmap_getword(args, word);
589 if (val)
590 incore |= mask;
591 else
592 incore &= ~mask;
593 xfs_rtbitmap_setword(args, word, incore);
594 i = lastbit - bit;
595 /*
596 * Go on to the next block if that's where the next word is
597 * and we need the next word.
598 */
599 if (++word == mp->m_blockwsize && i < len) {
600 /*
601 * Log the changed part of this block.
602 * Get the next one.
603 */
604 xfs_trans_log_rtbitmap(args, firstword, word);
605 error = xfs_rtbitmap_read_buf(args, ++block);
606 if (error)
607 return error;
608
609 firstword = word = 0;
610 }
611 } else {
612 /*
613 * Starting on a word boundary, no partial word.
614 */
615 i = 0;
616 }
617 /*
618 * Loop over whole words in buffers. When we use up one buffer
619 * we move on to the next one.
620 */
621 while (len - i >= XFS_NBWORD) {
622 /*
623 * Set the word value correctly.
624 */
625 xfs_rtbitmap_setword(args, word, val);
626 i += XFS_NBWORD;
627 /*
628 * Go on to the next block if that's where the next word is
629 * and we need the next word.
630 */
631 if (++word == mp->m_blockwsize && i < len) {
632 /*
633 * Log the changed part of this block.
634 * Get the next one.
635 */
636 xfs_trans_log_rtbitmap(args, firstword, word);
637 error = xfs_rtbitmap_read_buf(args, ++block);
638 if (error)
639 return error;
640
641 firstword = word = 0;
642 }
643 }
644 /*
645 * If not ending on a word boundary, deal with the last
646 * (partial) word.
647 */
648 if ((lastbit = len - i)) {
649 /*
650 * Compute a mask of relevant bits.
651 */
652 mask = ((xfs_rtword_t)1 << lastbit) - 1;
653 /*
654 * Set/clear the active bits.
655 */
656 incore = xfs_rtbitmap_getword(args, word);
657 if (val)
658 incore |= mask;
659 else
660 incore &= ~mask;
661 xfs_rtbitmap_setword(args, word, incore);
662 word++;
663 }
664 /*
665 * Log any remaining changed bytes.
666 */
667 if (word > firstword)
668 xfs_trans_log_rtbitmap(args, firstword, word);
669 return 0;
670}
671
672/*
673 * Mark an extent specified by start and len freed.
674 * Updates all the summary information as well as the bitmap.
675 */
676int
677xfs_rtfree_range(
678 struct xfs_rtalloc_args *args,
679 xfs_rtxnum_t start, /* starting rtext to free */
680 xfs_rtxlen_t len) /* in/out: summary block number */
681{
682 struct xfs_mount *mp = args->mp;
683 xfs_rtxnum_t end; /* end of the freed extent */
684 int error; /* error value */
685 xfs_rtxnum_t postblock; /* first rtext freed > end */
686 xfs_rtxnum_t preblock; /* first rtext freed < start */
687
688 end = start + len - 1;
689 /*
690 * Modify the bitmap to mark this extent freed.
691 */
692 error = xfs_rtmodify_range(args, start, len, 1);
693 if (error) {
694 return error;
695 }
696 /*
697 * Assume we're freeing out of the middle of an allocated extent.
698 * We need to find the beginning and end of the extent so we can
699 * properly update the summary.
700 */
701 error = xfs_rtfind_back(args, start, 0, &preblock);
702 if (error) {
703 return error;
704 }
705 /*
706 * Find the next allocated block (end of allocated extent).
707 */
708 error = xfs_rtfind_forw(args, end, mp->m_sb.sb_rextents - 1,
709 &postblock);
710 if (error)
711 return error;
712 /*
713 * If there are blocks not being freed at the front of the
714 * old extent, add summary data for them to be allocated.
715 */
716 if (preblock < start) {
717 error = xfs_rtmodify_summary(args,
718 xfs_highbit64(start - preblock),
719 xfs_rtx_to_rbmblock(mp, preblock), -1);
720 if (error) {
721 return error;
722 }
723 }
724 /*
725 * If there are blocks not being freed at the end of the
726 * old extent, add summary data for them to be allocated.
727 */
728 if (postblock > end) {
729 error = xfs_rtmodify_summary(args,
730 xfs_highbit64(postblock - end),
731 xfs_rtx_to_rbmblock(mp, end + 1), -1);
732 if (error) {
733 return error;
734 }
735 }
736 /*
737 * Increment the summary information corresponding to the entire
738 * (new) free extent.
739 */
740 return xfs_rtmodify_summary(args,
741 xfs_highbit64(postblock + 1 - preblock),
742 xfs_rtx_to_rbmblock(mp, preblock), 1);
743}
744
745/*
746 * Check that the given range is either all allocated (val = 0) or
747 * all free (val = 1).
748 */
749int
750xfs_rtcheck_range(
751 struct xfs_rtalloc_args *args,
752 xfs_rtxnum_t start, /* starting rtext number of extent */
753 xfs_rtxlen_t len, /* length of extent */
754 int val, /* 1 for free, 0 for allocated */
755 xfs_rtxnum_t *new, /* out: first rtext not matching */
756 int *stat) /* out: 1 for matches, 0 for not */
757{
758 struct xfs_mount *mp = args->mp;
759 int bit; /* bit number in the word */
760 xfs_fileoff_t block; /* bitmap block number */
761 int error;
762 xfs_rtxnum_t i; /* current bit number rel. to start */
763 xfs_rtxnum_t lastbit; /* last useful bit in word */
764 xfs_rtword_t mask; /* mask of relevant bits for value */
765 xfs_rtword_t wdiff; /* difference from wanted value */
766 xfs_rtword_t incore;
767 unsigned int word; /* word number in the buffer */
768
769 /*
770 * Compute starting bitmap block number
771 */
772 block = xfs_rtx_to_rbmblock(mp, start);
773 /*
774 * Read the bitmap block.
775 */
776 error = xfs_rtbitmap_read_buf(args, block);
777 if (error)
778 return error;
779
780 /*
781 * Compute the starting word's address, and starting bit.
782 */
783 word = xfs_rtx_to_rbmword(mp, start);
784 bit = (int)(start & (XFS_NBWORD - 1));
785 /*
786 * 0 (allocated) => all zero's; 1 (free) => all one's.
787 */
788 val = -val;
789 /*
790 * If not starting on a word boundary, deal with the first
791 * (partial) word.
792 */
793 if (bit) {
794 /*
795 * Compute first bit not examined.
796 */
797 lastbit = min(bit + len, XFS_NBWORD);
798 /*
799 * Mask of relevant bits.
800 */
801 mask = (((xfs_rtword_t)1 << (lastbit - bit)) - 1) << bit;
802 /*
803 * Compute difference between actual and desired value.
804 */
805 incore = xfs_rtbitmap_getword(args, word);
806 if ((wdiff = (incore ^ val) & mask)) {
807 /*
808 * Different, compute first wrong bit and return.
809 */
810 i = xfs_lowbit32(wdiff) - bit;
811 *new = start + i;
812 *stat = 0;
813 return 0;
814 }
815 i = lastbit - bit;
816 /*
817 * Go on to next block if that's where the next word is
818 * and we need the next word.
819 */
820 if (++word == mp->m_blockwsize && i < len) {
821 /*
822 * If done with this block, get the next one.
823 */
824 error = xfs_rtbitmap_read_buf(args, ++block);
825 if (error)
826 return error;
827
828 word = 0;
829 }
830 } else {
831 /*
832 * Starting on a word boundary, no partial word.
833 */
834 i = 0;
835 }
836 /*
837 * Loop over whole words in buffers. When we use up one buffer
838 * we move on to the next one.
839 */
840 while (len - i >= XFS_NBWORD) {
841 /*
842 * Compute difference between actual and desired value.
843 */
844 incore = xfs_rtbitmap_getword(args, word);
845 if ((wdiff = incore ^ val)) {
846 /*
847 * Different, compute first wrong bit and return.
848 */
849 i += xfs_lowbit32(wdiff);
850 *new = start + i;
851 *stat = 0;
852 return 0;
853 }
854 i += XFS_NBWORD;
855 /*
856 * Go on to next block if that's where the next word is
857 * and we need the next word.
858 */
859 if (++word == mp->m_blockwsize && i < len) {
860 /*
861 * If done with this block, get the next one.
862 */
863 error = xfs_rtbitmap_read_buf(args, ++block);
864 if (error)
865 return error;
866
867 word = 0;
868 }
869 }
870 /*
871 * If not ending on a word boundary, deal with the last
872 * (partial) word.
873 */
874 if ((lastbit = len - i)) {
875 /*
876 * Mask of relevant bits.
877 */
878 mask = ((xfs_rtword_t)1 << lastbit) - 1;
879 /*
880 * Compute difference between actual and desired value.
881 */
882 incore = xfs_rtbitmap_getword(args, word);
883 if ((wdiff = (incore ^ val) & mask)) {
884 /*
885 * Different, compute first wrong bit and return.
886 */
887 i += xfs_lowbit32(wdiff);
888 *new = start + i;
889 *stat = 0;
890 return 0;
891 } else
892 i = len;
893 }
894 /*
895 * Successful, return.
896 */
897 *new = start + i;
898 *stat = 1;
899 return 0;
900}
901
902#ifdef DEBUG
903/*
904 * Check that the given extent (block range) is allocated already.
905 */
906STATIC int
907xfs_rtcheck_alloc_range(
908 struct xfs_rtalloc_args *args,
909 xfs_rtxnum_t start, /* starting rtext number of extent */
910 xfs_rtxlen_t len) /* length of extent */
911{
912 xfs_rtxnum_t new; /* dummy for xfs_rtcheck_range */
913 int stat;
914 int error;
915
916 error = xfs_rtcheck_range(args, start, len, 0, &new, &stat);
917 if (error)
918 return error;
919 ASSERT(stat);
920 return 0;
921}
922#else
923#define xfs_rtcheck_alloc_range(a,b,l) (0)
924#endif
925/*
926 * Free an extent in the realtime subvolume. Length is expressed in
927 * realtime extents, as is the block number.
928 */
929int
930xfs_rtfree_extent(
931 struct xfs_trans *tp, /* transaction pointer */
932 xfs_rtxnum_t start, /* starting rtext number to free */
933 xfs_rtxlen_t len) /* length of extent freed */
934{
935 struct xfs_mount *mp = tp->t_mountp;
936 struct xfs_rtalloc_args args = {
937 .mp = mp,
938 .tp = tp,
939 };
940 int error;
941 struct timespec64 atime;
942
943 ASSERT(mp->m_rbmip->i_itemp != NULL);
944 xfs_assert_ilocked(mp->m_rbmip, XFS_ILOCK_EXCL);
945
946 error = xfs_rtcheck_alloc_range(&args, start, len);
947 if (error)
948 return error;
949
950 /*
951 * Free the range of realtime blocks.
952 */
953 error = xfs_rtfree_range(&args, start, len);
954 if (error)
955 goto out;
956
957 /*
958 * Mark more blocks free in the superblock.
959 */
960 xfs_trans_mod_sb(tp, XFS_TRANS_SB_FREXTENTS, (long)len);
961 /*
962 * If we've now freed all the blocks, reset the file sequence
963 * number to 0.
964 */
965 if (tp->t_frextents_delta + mp->m_sb.sb_frextents ==
966 mp->m_sb.sb_rextents) {
967 if (!(mp->m_rbmip->i_diflags & XFS_DIFLAG_NEWRTBM))
968 mp->m_rbmip->i_diflags |= XFS_DIFLAG_NEWRTBM;
969
970 atime = inode_get_atime(VFS_I(mp->m_rbmip));
971 atime.tv_sec = 0;
972 inode_set_atime_to_ts(VFS_I(mp->m_rbmip), atime);
973 xfs_trans_log_inode(tp, mp->m_rbmip, XFS_ILOG_CORE);
974 }
975 error = 0;
976out:
977 xfs_rtbuf_cache_relse(&args);
978 return error;
979}
980
981/*
982 * Free some blocks in the realtime subvolume. rtbno and rtlen are in units of
983 * rt blocks, not rt extents; must be aligned to the rt extent size; and rtlen
984 * cannot exceed XFS_MAX_BMBT_EXTLEN.
985 */
986int
987xfs_rtfree_blocks(
988 struct xfs_trans *tp,
989 xfs_fsblock_t rtbno,
990 xfs_filblks_t rtlen)
991{
992 struct xfs_mount *mp = tp->t_mountp;
993 xfs_rtxnum_t start;
994 xfs_filblks_t len;
995 xfs_extlen_t mod;
996
997 ASSERT(rtlen <= XFS_MAX_BMBT_EXTLEN);
998
999 len = xfs_rtb_to_rtxrem(mp, rtlen, &mod);
1000 if (mod) {
1001 ASSERT(mod == 0);
1002 return -EIO;
1003 }
1004
1005 start = xfs_rtb_to_rtxrem(mp, rtbno, &mod);
1006 if (mod) {
1007 ASSERT(mod == 0);
1008 return -EIO;
1009 }
1010
1011 return xfs_rtfree_extent(tp, start, len);
1012}
1013
1014/* Find all the free records within a given range. */
1015int
1016xfs_rtalloc_query_range(
1017 struct xfs_mount *mp,
1018 struct xfs_trans *tp,
1019 const struct xfs_rtalloc_rec *low_rec,
1020 const struct xfs_rtalloc_rec *high_rec,
1021 xfs_rtalloc_query_range_fn fn,
1022 void *priv)
1023{
1024 struct xfs_rtalloc_args args = {
1025 .mp = mp,
1026 .tp = tp,
1027 };
1028 struct xfs_rtalloc_rec rec;
1029 xfs_rtxnum_t rtstart;
1030 xfs_rtxnum_t rtend;
1031 xfs_rtxnum_t high_key;
1032 int is_free;
1033 int error = 0;
1034
1035 if (low_rec->ar_startext > high_rec->ar_startext)
1036 return -EINVAL;
1037 if (low_rec->ar_startext >= mp->m_sb.sb_rextents ||
1038 low_rec->ar_startext == high_rec->ar_startext)
1039 return 0;
1040
1041 high_key = min(high_rec->ar_startext, mp->m_sb.sb_rextents - 1);
1042
1043 /* Iterate the bitmap, looking for discrepancies. */
1044 rtstart = low_rec->ar_startext;
1045 while (rtstart <= high_key) {
1046 /* Is the first block free? */
1047 error = xfs_rtcheck_range(&args, rtstart, 1, 1, &rtend,
1048 &is_free);
1049 if (error)
1050 break;
1051
1052 /* How long does the extent go for? */
1053 error = xfs_rtfind_forw(&args, rtstart, high_key, &rtend);
1054 if (error)
1055 break;
1056
1057 if (is_free) {
1058 rec.ar_startext = rtstart;
1059 rec.ar_extcount = rtend - rtstart + 1;
1060
1061 error = fn(mp, tp, &rec, priv);
1062 if (error)
1063 break;
1064 }
1065
1066 rtstart = rtend + 1;
1067 }
1068
1069 xfs_rtbuf_cache_relse(&args);
1070 return error;
1071}
1072
1073/* Find all the free records. */
1074int
1075xfs_rtalloc_query_all(
1076 struct xfs_mount *mp,
1077 struct xfs_trans *tp,
1078 xfs_rtalloc_query_range_fn fn,
1079 void *priv)
1080{
1081 struct xfs_rtalloc_rec keys[2];
1082
1083 keys[0].ar_startext = 0;
1084 keys[1].ar_startext = mp->m_sb.sb_rextents - 1;
1085 keys[0].ar_extcount = keys[1].ar_extcount = 0;
1086
1087 return xfs_rtalloc_query_range(mp, tp, &keys[0], &keys[1], fn, priv);
1088}
1089
1090/* Is the given extent all free? */
1091int
1092xfs_rtalloc_extent_is_free(
1093 struct xfs_mount *mp,
1094 struct xfs_trans *tp,
1095 xfs_rtxnum_t start,
1096 xfs_rtxlen_t len,
1097 bool *is_free)
1098{
1099 struct xfs_rtalloc_args args = {
1100 .mp = mp,
1101 .tp = tp,
1102 };
1103 xfs_rtxnum_t end;
1104 int matches;
1105 int error;
1106
1107 error = xfs_rtcheck_range(&args, start, len, 1, &end, &matches);
1108 xfs_rtbuf_cache_relse(&args);
1109 if (error)
1110 return error;
1111
1112 *is_free = matches;
1113 return 0;
1114}
1115
1116/*
1117 * Compute the number of rtbitmap blocks needed to track the given number of rt
1118 * extents.
1119 */
1120xfs_filblks_t
1121xfs_rtbitmap_blockcount(
1122 struct xfs_mount *mp,
1123 xfs_rtbxlen_t rtextents)
1124{
1125 return howmany_64(rtextents, NBBY * mp->m_sb.sb_blocksize);
1126}
1127
1128/*
1129 * Compute the number of rtbitmap words needed to populate every block of a
1130 * bitmap that is large enough to track the given number of rt extents.
1131 */
1132unsigned long long
1133xfs_rtbitmap_wordcount(
1134 struct xfs_mount *mp,
1135 xfs_rtbxlen_t rtextents)
1136{
1137 xfs_filblks_t blocks;
1138
1139 blocks = xfs_rtbitmap_blockcount(mp, rtextents);
1140 return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
1141}
1142
1143/* Compute the number of rtsummary blocks needed to track the given rt space. */
1144xfs_filblks_t
1145xfs_rtsummary_blockcount(
1146 struct xfs_mount *mp,
1147 unsigned int rsumlevels,
1148 xfs_extlen_t rbmblocks)
1149{
1150 unsigned long long rsumwords;
1151
1152 rsumwords = (unsigned long long)rsumlevels * rbmblocks;
1153 return XFS_B_TO_FSB(mp, rsumwords << XFS_WORDLOG);
1154}
1155
1156/*
1157 * Compute the number of rtsummary info words needed to populate every block of
1158 * a summary file that is large enough to track the given rt space.
1159 */
1160unsigned long long
1161xfs_rtsummary_wordcount(
1162 struct xfs_mount *mp,
1163 unsigned int rsumlevels,
1164 xfs_extlen_t rbmblocks)
1165{
1166 xfs_filblks_t blocks;
1167
1168 blocks = xfs_rtsummary_blockcount(mp, rsumlevels, rbmblocks);
1169 return XFS_FSB_TO_B(mp, blocks) >> XFS_WORDLOG;
1170}
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}