2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 #include "xfs_format.h"
21 #include "xfs_log_format.h"
22 #include "xfs_shared.h"
23 #include "xfs_trans_resv.h"
26 #include "xfs_mount.h"
27 #include "xfs_defer.h"
28 #include "xfs_inode.h"
29 #include "xfs_btree.h"
31 #include "xfs_alloc_btree.h"
32 #include "xfs_alloc.h"
33 #include "xfs_extent_busy.h"
34 #include "xfs_error.h"
35 #include "xfs_cksum.h"
36 #include "xfs_trace.h"
37 #include "xfs_trans.h"
38 #include "xfs_buf_item.h"
40 #include "xfs_ag_resv.h"
42 struct workqueue_struct *xfs_alloc_wq;
44 #define XFS_ABSDIFF(a,b) (((a) <= (b)) ? ((b) - (a)) : ((a) - (b)))
46 #define XFSA_FIXUP_BNO_OK 1
47 #define XFSA_FIXUP_CNT_OK 2
49 STATIC int xfs_alloc_ag_vextent_exact(xfs_alloc_arg_t *);
50 STATIC int xfs_alloc_ag_vextent_near(xfs_alloc_arg_t *);
51 STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *);
52 STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *,
53 xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *);
59 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
60 return XFS_RMAP_BLOCK(mp) + 1;
61 if (xfs_sb_version_hasfinobt(&mp->m_sb))
62 return XFS_FIBT_BLOCK(mp) + 1;
63 return XFS_IBT_BLOCK(mp) + 1;
70 if (xfs_sb_version_hasreflink(&mp->m_sb))
71 return xfs_refc_block(mp) + 1;
72 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
73 return XFS_RMAP_BLOCK(mp) + 1;
74 if (xfs_sb_version_hasfinobt(&mp->m_sb))
75 return XFS_FIBT_BLOCK(mp) + 1;
76 return XFS_IBT_BLOCK(mp) + 1;
80 * In order to avoid ENOSPC-related deadlock caused by out-of-order locking of
81 * AGF buffer (PV 947395), we place constraints on the relationship among
82 * actual allocations for data blocks, freelist blocks, and potential file data
83 * bmap btree blocks. However, these restrictions may result in no actual space
84 * allocated for a delayed extent, for example, a data block in a certain AG is
85 * allocated but there is no additional block for the additional bmap btree
86 * block due to a split of the bmap btree of the file. The result of this may
87 * lead to an infinite loop when the file gets flushed to disk and all delayed
88 * extents need to be actually allocated. To get around this, we explicitly set
89 * aside a few blocks which will not be reserved in delayed allocation.
91 * We need to reserve 4 fsbs _per AG_ for the freelist and 4 more to handle a
92 * potential split of the file's bmap btree.
98 return mp->m_sb.sb_agcount * (XFS_ALLOC_AGFL_RESERVE + 4);
102 * When deciding how much space to allocate out of an AG, we limit the
103 * allocation maximum size to the size the AG. However, we cannot use all the
104 * blocks in the AG - some are permanently used by metadata. These
105 * blocks are generally:
106 * - the AG superblock, AGF, AGI and AGFL
107 * - the AGF (bno and cnt) and AGI btree root blocks, and optionally
108 * the AGI free inode and rmap btree root blocks.
109 * - blocks on the AGFL according to xfs_alloc_set_aside() limits
110 * - the rmapbt root block
112 * The AG headers are sector sized, so the amount of space they take up is
113 * dependent on filesystem geometry. The others are all single blocks.
116 xfs_alloc_ag_max_usable(
117 struct xfs_mount *mp)
121 blocks = XFS_BB_TO_FSB(mp, XFS_FSS_TO_BB(mp, 4)); /* ag headers */
122 blocks += XFS_ALLOC_AGFL_RESERVE;
123 blocks += 3; /* AGF, AGI btree root blocks */
124 if (xfs_sb_version_hasfinobt(&mp->m_sb))
125 blocks++; /* finobt root block */
126 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
127 blocks++; /* rmap root block */
128 if (xfs_sb_version_hasreflink(&mp->m_sb))
129 blocks++; /* refcount root block */
131 return mp->m_sb.sb_agblocks - blocks;
135 * Lookup the record equal to [bno, len] in the btree given by cur.
137 STATIC int /* error */
139 struct xfs_btree_cur *cur, /* btree cursor */
140 xfs_agblock_t bno, /* starting block of extent */
141 xfs_extlen_t len, /* length of extent */
142 int *stat) /* success/failure */
144 cur->bc_rec.a.ar_startblock = bno;
145 cur->bc_rec.a.ar_blockcount = len;
146 return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
150 * Lookup the first record greater than or equal to [bno, len]
151 * in the btree given by cur.
155 struct xfs_btree_cur *cur, /* btree cursor */
156 xfs_agblock_t bno, /* starting block of extent */
157 xfs_extlen_t len, /* length of extent */
158 int *stat) /* success/failure */
160 cur->bc_rec.a.ar_startblock = bno;
161 cur->bc_rec.a.ar_blockcount = len;
162 return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
166 * Lookup the first record less than or equal to [bno, len]
167 * in the btree given by cur.
169 static int /* error */
171 struct xfs_btree_cur *cur, /* btree cursor */
172 xfs_agblock_t bno, /* starting block of extent */
173 xfs_extlen_t len, /* length of extent */
174 int *stat) /* success/failure */
176 cur->bc_rec.a.ar_startblock = bno;
177 cur->bc_rec.a.ar_blockcount = len;
178 return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
182 * Update the record referred to by cur to the value given
184 * This either works (return 0) or gets an EFSCORRUPTED error.
186 STATIC int /* error */
188 struct xfs_btree_cur *cur, /* btree cursor */
189 xfs_agblock_t bno, /* starting block of extent */
190 xfs_extlen_t len) /* length of extent */
192 union xfs_btree_rec rec;
194 rec.alloc.ar_startblock = cpu_to_be32(bno);
195 rec.alloc.ar_blockcount = cpu_to_be32(len);
196 return xfs_btree_update(cur, &rec);
200 * Get the data from the pointed-to record.
204 struct xfs_btree_cur *cur, /* btree cursor */
205 xfs_agblock_t *bno, /* output: starting block of extent */
206 xfs_extlen_t *len, /* output: length of extent */
207 int *stat) /* output: success/failure */
209 union xfs_btree_rec *rec;
212 error = xfs_btree_get_rec(cur, &rec, stat);
213 if (!error && *stat == 1) {
214 *bno = be32_to_cpu(rec->alloc.ar_startblock);
215 *len = be32_to_cpu(rec->alloc.ar_blockcount);
221 * Compute aligned version of the found extent.
222 * Takes alignment and min length into account.
225 xfs_alloc_compute_aligned(
226 xfs_alloc_arg_t *args, /* allocation argument structure */
227 xfs_agblock_t foundbno, /* starting block in found extent */
228 xfs_extlen_t foundlen, /* length in found extent */
229 xfs_agblock_t *resbno, /* result block number */
230 xfs_extlen_t *reslen) /* result length */
236 /* Trim busy sections out of found extent */
237 xfs_extent_busy_trim(args, foundbno, foundlen, &bno, &len);
240 * If we have a largish extent that happens to start before min_agbno,
241 * see if we can shift it into range...
243 if (bno < args->min_agbno && bno + len > args->min_agbno) {
244 diff = args->min_agbno - bno;
251 if (args->alignment > 1 && len >= args->minlen) {
252 xfs_agblock_t aligned_bno = roundup(bno, args->alignment);
254 diff = aligned_bno - bno;
256 *resbno = aligned_bno;
257 *reslen = diff >= len ? 0 : len - diff;
265 * Compute best start block and diff for "near" allocations.
266 * freelen >= wantlen already checked by caller.
268 STATIC xfs_extlen_t /* difference value (absolute) */
269 xfs_alloc_compute_diff(
270 xfs_agblock_t wantbno, /* target starting block */
271 xfs_extlen_t wantlen, /* target length */
272 xfs_extlen_t alignment, /* target alignment */
273 int datatype, /* are we allocating data? */
274 xfs_agblock_t freebno, /* freespace's starting block */
275 xfs_extlen_t freelen, /* freespace's length */
276 xfs_agblock_t *newbnop) /* result: best start block from free */
278 xfs_agblock_t freeend; /* end of freespace extent */
279 xfs_agblock_t newbno1; /* return block number */
280 xfs_agblock_t newbno2; /* other new block number */
281 xfs_extlen_t newlen1=0; /* length with newbno1 */
282 xfs_extlen_t newlen2=0; /* length with newbno2 */
283 xfs_agblock_t wantend; /* end of target extent */
284 bool userdata = xfs_alloc_is_userdata(datatype);
286 ASSERT(freelen >= wantlen);
287 freeend = freebno + freelen;
288 wantend = wantbno + wantlen;
290 * We want to allocate from the start of a free extent if it is past
291 * the desired block or if we are allocating user data and the free
292 * extent is before desired block. The second case is there to allow
293 * for contiguous allocation from the remaining free space if the file
294 * grows in the short term.
296 if (freebno >= wantbno || (userdata && freeend < wantend)) {
297 if ((newbno1 = roundup(freebno, alignment)) >= freeend)
298 newbno1 = NULLAGBLOCK;
299 } else if (freeend >= wantend && alignment > 1) {
300 newbno1 = roundup(wantbno, alignment);
301 newbno2 = newbno1 - alignment;
302 if (newbno1 >= freeend)
303 newbno1 = NULLAGBLOCK;
305 newlen1 = XFS_EXTLEN_MIN(wantlen, freeend - newbno1);
306 if (newbno2 < freebno)
307 newbno2 = NULLAGBLOCK;
309 newlen2 = XFS_EXTLEN_MIN(wantlen, freeend - newbno2);
310 if (newbno1 != NULLAGBLOCK && newbno2 != NULLAGBLOCK) {
311 if (newlen1 < newlen2 ||
312 (newlen1 == newlen2 &&
313 XFS_ABSDIFF(newbno1, wantbno) >
314 XFS_ABSDIFF(newbno2, wantbno)))
316 } else if (newbno2 != NULLAGBLOCK)
318 } else if (freeend >= wantend) {
320 } else if (alignment > 1) {
321 newbno1 = roundup(freeend - wantlen, alignment);
322 if (newbno1 > freeend - wantlen &&
323 newbno1 - alignment >= freebno)
324 newbno1 -= alignment;
325 else if (newbno1 >= freeend)
326 newbno1 = NULLAGBLOCK;
328 newbno1 = freeend - wantlen;
330 return newbno1 == NULLAGBLOCK ? 0 : XFS_ABSDIFF(newbno1, wantbno);
334 * Fix up the length, based on mod and prod.
335 * len should be k * prod + mod for some k.
336 * If len is too small it is returned unchanged.
337 * If len hits maxlen it is left alone.
341 xfs_alloc_arg_t *args) /* allocation argument structure */
346 ASSERT(args->mod < args->prod);
348 ASSERT(rlen >= args->minlen);
349 ASSERT(rlen <= args->maxlen);
350 if (args->prod <= 1 || rlen < args->mod || rlen == args->maxlen ||
351 (args->mod == 0 && rlen < args->prod))
353 k = rlen % args->prod;
357 rlen = rlen - (k - args->mod);
359 rlen = rlen - args->prod + (args->mod - k);
360 /* casts to (int) catch length underflows */
361 if ((int)rlen < (int)args->minlen)
363 ASSERT(rlen >= args->minlen && rlen <= args->maxlen);
364 ASSERT(rlen % args->prod == args->mod);
365 ASSERT(args->pag->pagf_freeblks + args->pag->pagf_flcount >=
366 rlen + args->minleft);
371 * Update the two btrees, logically removing from freespace the extent
372 * starting at rbno, rlen blocks. The extent is contained within the
373 * actual (current) free extent fbno for flen blocks.
374 * Flags are passed in indicating whether the cursors are set to the
377 STATIC int /* error code */
378 xfs_alloc_fixup_trees(
379 xfs_btree_cur_t *cnt_cur, /* cursor for by-size btree */
380 xfs_btree_cur_t *bno_cur, /* cursor for by-block btree */
381 xfs_agblock_t fbno, /* starting block of free extent */
382 xfs_extlen_t flen, /* length of free extent */
383 xfs_agblock_t rbno, /* starting block of returned extent */
384 xfs_extlen_t rlen, /* length of returned extent */
385 int flags) /* flags, XFSA_FIXUP_... */
387 int error; /* error code */
388 int i; /* operation results */
389 xfs_agblock_t nfbno1; /* first new free startblock */
390 xfs_agblock_t nfbno2; /* second new free startblock */
391 xfs_extlen_t nflen1=0; /* first new free length */
392 xfs_extlen_t nflen2=0; /* second new free length */
393 struct xfs_mount *mp;
398 * Look up the record in the by-size tree if necessary.
400 if (flags & XFSA_FIXUP_CNT_OK) {
402 if ((error = xfs_alloc_get_rec(cnt_cur, &nfbno1, &nflen1, &i)))
404 XFS_WANT_CORRUPTED_RETURN(mp,
405 i == 1 && nfbno1 == fbno && nflen1 == flen);
408 if ((error = xfs_alloc_lookup_eq(cnt_cur, fbno, flen, &i)))
410 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
413 * Look up the record in the by-block tree if necessary.
415 if (flags & XFSA_FIXUP_BNO_OK) {
417 if ((error = xfs_alloc_get_rec(bno_cur, &nfbno1, &nflen1, &i)))
419 XFS_WANT_CORRUPTED_RETURN(mp,
420 i == 1 && nfbno1 == fbno && nflen1 == flen);
423 if ((error = xfs_alloc_lookup_eq(bno_cur, fbno, flen, &i)))
425 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
429 if (bno_cur->bc_nlevels == 1 && cnt_cur->bc_nlevels == 1) {
430 struct xfs_btree_block *bnoblock;
431 struct xfs_btree_block *cntblock;
433 bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_bufs[0]);
434 cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_bufs[0]);
436 XFS_WANT_CORRUPTED_RETURN(mp,
437 bnoblock->bb_numrecs == cntblock->bb_numrecs);
442 * Deal with all four cases: the allocated record is contained
443 * within the freespace record, so we can have new freespace
444 * at either (or both) end, or no freespace remaining.
446 if (rbno == fbno && rlen == flen)
447 nfbno1 = nfbno2 = NULLAGBLOCK;
448 else if (rbno == fbno) {
449 nfbno1 = rbno + rlen;
450 nflen1 = flen - rlen;
451 nfbno2 = NULLAGBLOCK;
452 } else if (rbno + rlen == fbno + flen) {
454 nflen1 = flen - rlen;
455 nfbno2 = NULLAGBLOCK;
458 nflen1 = rbno - fbno;
459 nfbno2 = rbno + rlen;
460 nflen2 = (fbno + flen) - nfbno2;
463 * Delete the entry from the by-size btree.
465 if ((error = xfs_btree_delete(cnt_cur, &i)))
467 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
469 * Add new by-size btree entry(s).
471 if (nfbno1 != NULLAGBLOCK) {
472 if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno1, nflen1, &i)))
474 XFS_WANT_CORRUPTED_RETURN(mp, i == 0);
475 if ((error = xfs_btree_insert(cnt_cur, &i)))
477 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
479 if (nfbno2 != NULLAGBLOCK) {
480 if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno2, nflen2, &i)))
482 XFS_WANT_CORRUPTED_RETURN(mp, i == 0);
483 if ((error = xfs_btree_insert(cnt_cur, &i)))
485 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
488 * Fix up the by-block btree entry(s).
490 if (nfbno1 == NULLAGBLOCK) {
492 * No remaining freespace, just delete the by-block tree entry.
494 if ((error = xfs_btree_delete(bno_cur, &i)))
496 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
499 * Update the by-block entry to start later|be shorter.
501 if ((error = xfs_alloc_update(bno_cur, nfbno1, nflen1)))
504 if (nfbno2 != NULLAGBLOCK) {
506 * 2 resulting free entries, need to add one.
508 if ((error = xfs_alloc_lookup_eq(bno_cur, nfbno2, nflen2, &i)))
510 XFS_WANT_CORRUPTED_RETURN(mp, i == 0);
511 if ((error = xfs_btree_insert(bno_cur, &i)))
513 XFS_WANT_CORRUPTED_RETURN(mp, i == 1);
522 struct xfs_mount *mp = bp->b_target->bt_mount;
523 struct xfs_agfl *agfl = XFS_BUF_TO_AGFL(bp);
526 if (!uuid_equal(&agfl->agfl_uuid, &mp->m_sb.sb_meta_uuid))
528 if (be32_to_cpu(agfl->agfl_magicnum) != XFS_AGFL_MAGIC)
531 * during growfs operations, the perag is not fully initialised,
532 * so we can't use it for any useful checking. growfs ensures we can't
533 * use it by using uncached buffers that don't have the perag attached
534 * so we can detect and avoid this problem.
536 if (bp->b_pag && be32_to_cpu(agfl->agfl_seqno) != bp->b_pag->pag_agno)
539 for (i = 0; i < XFS_AGFL_SIZE(mp); i++) {
540 if (be32_to_cpu(agfl->agfl_bno[i]) != NULLAGBLOCK &&
541 be32_to_cpu(agfl->agfl_bno[i]) >= mp->m_sb.sb_agblocks)
545 return xfs_log_check_lsn(mp,
546 be64_to_cpu(XFS_BUF_TO_AGFL(bp)->agfl_lsn));
550 xfs_agfl_read_verify(
553 struct xfs_mount *mp = bp->b_target->bt_mount;
556 * There is no verification of non-crc AGFLs because mkfs does not
557 * initialise the AGFL to zero or NULL. Hence the only valid part of the
558 * AGFL is what the AGF says is active. We can't get to the AGF, so we
559 * can't verify just those entries are valid.
561 if (!xfs_sb_version_hascrc(&mp->m_sb))
564 if (!xfs_buf_verify_cksum(bp, XFS_AGFL_CRC_OFF))
565 xfs_buf_ioerror(bp, -EFSBADCRC);
566 else if (!xfs_agfl_verify(bp))
567 xfs_buf_ioerror(bp, -EFSCORRUPTED);
570 xfs_verifier_error(bp);
574 xfs_agfl_write_verify(
577 struct xfs_mount *mp = bp->b_target->bt_mount;
578 struct xfs_buf_log_item *bip = bp->b_fspriv;
580 /* no verification of non-crc AGFLs */
581 if (!xfs_sb_version_hascrc(&mp->m_sb))
584 if (!xfs_agfl_verify(bp)) {
585 xfs_buf_ioerror(bp, -EFSCORRUPTED);
586 xfs_verifier_error(bp);
591 XFS_BUF_TO_AGFL(bp)->agfl_lsn = cpu_to_be64(bip->bli_item.li_lsn);
593 xfs_buf_update_cksum(bp, XFS_AGFL_CRC_OFF);
596 const struct xfs_buf_ops xfs_agfl_buf_ops = {
598 .verify_read = xfs_agfl_read_verify,
599 .verify_write = xfs_agfl_write_verify,
603 * Read in the allocation group free block array.
605 STATIC int /* error */
607 xfs_mount_t *mp, /* mount point structure */
608 xfs_trans_t *tp, /* transaction pointer */
609 xfs_agnumber_t agno, /* allocation group number */
610 xfs_buf_t **bpp) /* buffer for the ag free block array */
612 xfs_buf_t *bp; /* return value */
615 ASSERT(agno != NULLAGNUMBER);
616 error = xfs_trans_read_buf(
617 mp, tp, mp->m_ddev_targp,
618 XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)),
619 XFS_FSS_TO_BB(mp, 1), 0, &bp, &xfs_agfl_buf_ops);
622 xfs_buf_set_ref(bp, XFS_AGFL_REF);
628 xfs_alloc_update_counters(
629 struct xfs_trans *tp,
630 struct xfs_perag *pag,
631 struct xfs_buf *agbp,
634 struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
636 pag->pagf_freeblks += len;
637 be32_add_cpu(&agf->agf_freeblks, len);
639 xfs_trans_agblocks_delta(tp, len);
640 if (unlikely(be32_to_cpu(agf->agf_freeblks) >
641 be32_to_cpu(agf->agf_length)))
642 return -EFSCORRUPTED;
644 xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS);
649 * Allocation group level functions.
653 * Allocate a variable extent in the allocation group agno.
654 * Type and bno are used to determine where in the allocation group the
656 * Extent's length (returned in *len) will be between minlen and maxlen,
657 * and of the form k * prod + mod unless there's nothing that large.
658 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
660 STATIC int /* error */
661 xfs_alloc_ag_vextent(
662 xfs_alloc_arg_t *args) /* argument structure for allocation */
666 ASSERT(args->minlen > 0);
667 ASSERT(args->maxlen > 0);
668 ASSERT(args->minlen <= args->maxlen);
669 ASSERT(args->mod < args->prod);
670 ASSERT(args->alignment > 0);
673 * Branch to correct routine based on the type.
676 switch (args->type) {
677 case XFS_ALLOCTYPE_THIS_AG:
678 error = xfs_alloc_ag_vextent_size(args);
680 case XFS_ALLOCTYPE_NEAR_BNO:
681 error = xfs_alloc_ag_vextent_near(args);
683 case XFS_ALLOCTYPE_THIS_BNO:
684 error = xfs_alloc_ag_vextent_exact(args);
691 if (error || args->agbno == NULLAGBLOCK)
694 ASSERT(args->len >= args->minlen);
695 ASSERT(args->len <= args->maxlen);
696 ASSERT(!args->wasfromfl || args->resv != XFS_AG_RESV_AGFL);
697 ASSERT(args->agbno % args->alignment == 0);
699 /* if not file data, insert new block into the reverse map btree */
700 if (args->oinfo.oi_owner != XFS_RMAP_OWN_UNKNOWN) {
701 error = xfs_rmap_alloc(args->tp, args->agbp, args->agno,
702 args->agbno, args->len, &args->oinfo);
707 if (!args->wasfromfl) {
708 error = xfs_alloc_update_counters(args->tp, args->pag,
710 -((long)(args->len)));
714 ASSERT(!xfs_extent_busy_search(args->mp, args->agno,
715 args->agbno, args->len));
718 xfs_ag_resv_alloc_extent(args->pag, args->resv, args);
720 XFS_STATS_INC(args->mp, xs_allocx);
721 XFS_STATS_ADD(args->mp, xs_allocb, args->len);
726 * Allocate a variable extent at exactly agno/bno.
727 * Extent's length (returned in *len) will be between minlen and maxlen,
728 * and of the form k * prod + mod unless there's nothing that large.
729 * Return the starting a.g. block (bno), or NULLAGBLOCK if we can't do it.
731 STATIC int /* error */
732 xfs_alloc_ag_vextent_exact(
733 xfs_alloc_arg_t *args) /* allocation argument structure */
735 xfs_btree_cur_t *bno_cur;/* by block-number btree cursor */
736 xfs_btree_cur_t *cnt_cur;/* by count btree cursor */
738 xfs_agblock_t fbno; /* start block of found extent */
739 xfs_extlen_t flen; /* length of found extent */
740 xfs_agblock_t tbno; /* start block of trimmed extent */
741 xfs_extlen_t tlen; /* length of trimmed extent */
742 xfs_agblock_t tend; /* end block of trimmed extent */
743 int i; /* success/failure of operation */
745 ASSERT(args->alignment == 1);
748 * Allocate/initialize a cursor for the by-number freespace btree.
750 bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
751 args->agno, XFS_BTNUM_BNO);
754 * Lookup bno and minlen in the btree (minlen is irrelevant, really).
755 * Look for the closest free block <= bno, it must contain bno
756 * if any free block does.
758 error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i);
765 * Grab the freespace record.
767 error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i);
770 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
771 ASSERT(fbno <= args->agbno);
774 * Check for overlapping busy extents.
776 xfs_extent_busy_trim(args, fbno, flen, &tbno, &tlen);
779 * Give up if the start of the extent is busy, or the freespace isn't
780 * long enough for the minimum request.
782 if (tbno > args->agbno)
784 if (tlen < args->minlen)
787 if (tend < args->agbno + args->minlen)
791 * End of extent will be smaller of the freespace end and the
792 * maximal requested end.
794 * Fix the length according to mod and prod if given.
796 args->len = XFS_AGBLOCK_MIN(tend, args->agbno + args->maxlen)
798 xfs_alloc_fix_len(args);
799 ASSERT(args->agbno + args->len <= tend);
802 * We are allocating agbno for args->len
803 * Allocate/initialize a cursor for the by-size btree.
805 cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
806 args->agno, XFS_BTNUM_CNT);
807 ASSERT(args->agbno + args->len <=
808 be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
809 error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen, args->agbno,
810 args->len, XFSA_FIXUP_BNO_OK);
812 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
816 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
817 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
820 trace_xfs_alloc_exact_done(args);
824 /* Didn't find it, return null. */
825 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
826 args->agbno = NULLAGBLOCK;
827 trace_xfs_alloc_exact_notfound(args);
831 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
832 trace_xfs_alloc_exact_error(args);
837 * Search the btree in a given direction via the search cursor and compare
838 * the records found against the good extent we've already found.
841 xfs_alloc_find_best_extent(
842 struct xfs_alloc_arg *args, /* allocation argument structure */
843 struct xfs_btree_cur **gcur, /* good cursor */
844 struct xfs_btree_cur **scur, /* searching cursor */
845 xfs_agblock_t gdiff, /* difference for search comparison */
846 xfs_agblock_t *sbno, /* extent found by search */
847 xfs_extlen_t *slen, /* extent length */
848 xfs_agblock_t *sbnoa, /* aligned extent found by search */
849 xfs_extlen_t *slena, /* aligned extent length */
850 int dir) /* 0 = search right, 1 = search left */
857 /* The good extent is perfect, no need to search. */
862 * Look until we find a better one, run out of space or run off the end.
865 error = xfs_alloc_get_rec(*scur, sbno, slen, &i);
868 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
869 xfs_alloc_compute_aligned(args, *sbno, *slen, sbnoa, slena);
872 * The good extent is closer than this one.
875 if (*sbnoa > args->max_agbno)
877 if (*sbnoa >= args->agbno + gdiff)
880 if (*sbnoa < args->min_agbno)
882 if (*sbnoa <= args->agbno - gdiff)
887 * Same distance, compare length and pick the best.
889 if (*slena >= args->minlen) {
890 args->len = XFS_EXTLEN_MIN(*slena, args->maxlen);
891 xfs_alloc_fix_len(args);
893 sdiff = xfs_alloc_compute_diff(args->agbno, args->len,
895 args->datatype, *sbnoa,
899 * Choose closer size and invalidate other cursor.
907 error = xfs_btree_increment(*scur, 0, &i);
909 error = xfs_btree_decrement(*scur, 0, &i);
915 xfs_btree_del_cursor(*scur, XFS_BTREE_NOERROR);
920 xfs_btree_del_cursor(*gcur, XFS_BTREE_NOERROR);
925 /* caller invalidates cursors */
930 * Allocate a variable extent near bno in the allocation group agno.
931 * Extent's length (returned in len) will be between minlen and maxlen,
932 * and of the form k * prod + mod unless there's nothing that large.
933 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
935 STATIC int /* error */
936 xfs_alloc_ag_vextent_near(
937 xfs_alloc_arg_t *args) /* allocation argument structure */
939 xfs_btree_cur_t *bno_cur_gt; /* cursor for bno btree, right side */
940 xfs_btree_cur_t *bno_cur_lt; /* cursor for bno btree, left side */
941 xfs_btree_cur_t *cnt_cur; /* cursor for count btree */
942 xfs_agblock_t gtbno; /* start bno of right side entry */
943 xfs_agblock_t gtbnoa; /* aligned ... */
944 xfs_extlen_t gtdiff; /* difference to right side entry */
945 xfs_extlen_t gtlen; /* length of right side entry */
946 xfs_extlen_t gtlena; /* aligned ... */
947 xfs_agblock_t gtnew; /* useful start bno of right side */
948 int error; /* error code */
949 int i; /* result code, temporary */
950 int j; /* result code, temporary */
951 xfs_agblock_t ltbno; /* start bno of left side entry */
952 xfs_agblock_t ltbnoa; /* aligned ... */
953 xfs_extlen_t ltdiff; /* difference to left side entry */
954 xfs_extlen_t ltlen; /* length of left side entry */
955 xfs_extlen_t ltlena; /* aligned ... */
956 xfs_agblock_t ltnew; /* useful start bno of left side */
957 xfs_extlen_t rlen; /* length of returned extent */
961 * Randomly don't execute the first algorithm.
963 int dofirst; /* set to do first algorithm */
965 dofirst = prandom_u32() & 1;
968 /* handle unitialized agbno range so caller doesn't have to */
969 if (!args->min_agbno && !args->max_agbno)
970 args->max_agbno = args->mp->m_sb.sb_agblocks - 1;
971 ASSERT(args->min_agbno <= args->max_agbno);
973 /* clamp agbno to the range if it's outside */
974 if (args->agbno < args->min_agbno)
975 args->agbno = args->min_agbno;
976 if (args->agbno > args->max_agbno)
977 args->agbno = args->max_agbno;
987 * Get a cursor for the by-size btree.
989 cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
990 args->agno, XFS_BTNUM_CNT);
993 * See if there are any free extents as big as maxlen.
995 if ((error = xfs_alloc_lookup_ge(cnt_cur, 0, args->maxlen, &i)))
998 * If none, then pick up the last entry in the tree unless the
1002 if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, <bno,
1005 if (i == 0 || ltlen == 0) {
1006 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1007 trace_xfs_alloc_near_noentry(args);
1012 args->wasfromfl = 0;
1016 * If the requested extent is large wrt the freespaces available
1017 * in this a.g., then the cursor will be pointing to a btree entry
1018 * near the right edge of the tree. If it's in the last btree leaf
1019 * block, then we just examine all the entries in that block
1020 * that are big enough, and pick the best one.
1021 * This is written as a while loop so we can break out of it,
1022 * but we never loop back to the top.
1024 while (xfs_btree_islastblock(cnt_cur, 0)) {
1027 xfs_extlen_t blen=0;
1028 xfs_agblock_t bnew=0;
1035 * Start from the entry that lookup found, sequence through
1036 * all larger free blocks. If we're actually pointing at a
1037 * record smaller than maxlen, go to the start of this block,
1038 * and skip all those smaller than minlen.
1040 if (ltlen || args->alignment > 1) {
1041 cnt_cur->bc_ptrs[0] = 1;
1043 if ((error = xfs_alloc_get_rec(cnt_cur, <bno,
1046 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1047 if (ltlen >= args->minlen)
1049 if ((error = xfs_btree_increment(cnt_cur, 0, &i)))
1052 ASSERT(ltlen >= args->minlen);
1056 i = cnt_cur->bc_ptrs[0];
1057 for (j = 1, blen = 0, bdiff = 0;
1058 !error && j && (blen < args->maxlen || bdiff > 0);
1059 error = xfs_btree_increment(cnt_cur, 0, &j)) {
1061 * For each entry, decide if it's better than
1062 * the previous best entry.
1064 if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i)))
1066 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1067 xfs_alloc_compute_aligned(args, ltbno, ltlen,
1069 if (ltlena < args->minlen)
1071 if (ltbnoa < args->min_agbno || ltbnoa > args->max_agbno)
1073 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
1074 xfs_alloc_fix_len(args);
1075 ASSERT(args->len >= args->minlen);
1076 if (args->len < blen)
1078 ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
1079 args->alignment, args->datatype, ltbnoa,
1081 if (ltnew != NULLAGBLOCK &&
1082 (args->len > blen || ltdiff < bdiff)) {
1086 besti = cnt_cur->bc_ptrs[0];
1090 * It didn't work. We COULD be in a case where
1091 * there's a good record somewhere, so try again.
1096 * Point at the best entry, and retrieve it again.
1098 cnt_cur->bc_ptrs[0] = besti;
1099 if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i)))
1101 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1102 ASSERT(ltbno + ltlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
1106 * We are allocating starting at bnew for blen blocks.
1109 ASSERT(bnew >= ltbno);
1110 ASSERT(bnew + blen <= ltbno + ltlen);
1112 * Set up a cursor for the by-bno tree.
1114 bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp,
1115 args->agbp, args->agno, XFS_BTNUM_BNO);
1117 * Fix up the btree entries.
1119 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno,
1120 ltlen, bnew, blen, XFSA_FIXUP_CNT_OK)))
1122 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1123 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
1125 trace_xfs_alloc_near_first(args);
1130 * Search in the by-bno tree to the left and to the right
1131 * simultaneously, until in each case we find a space big enough,
1132 * or run into the edge of the tree. When we run into the edge,
1133 * we deallocate that cursor.
1134 * If both searches succeed, we compare the two spaces and pick
1136 * With alignment, it's possible for both to fail; the upper
1137 * level algorithm that picks allocation groups for allocations
1138 * is not supposed to do this.
1141 * Allocate and initialize the cursor for the leftward search.
1143 bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
1144 args->agno, XFS_BTNUM_BNO);
1146 * Lookup <= bno to find the leftward search's starting point.
1148 if ((error = xfs_alloc_lookup_le(bno_cur_lt, args->agbno, args->maxlen, &i)))
1152 * Didn't find anything; use this cursor for the rightward
1155 bno_cur_gt = bno_cur_lt;
1159 * Found something. Duplicate the cursor for the rightward search.
1161 else if ((error = xfs_btree_dup_cursor(bno_cur_lt, &bno_cur_gt)))
1164 * Increment the cursor, so we will point at the entry just right
1165 * of the leftward entry if any, or to the leftmost entry.
1167 if ((error = xfs_btree_increment(bno_cur_gt, 0, &i)))
1171 * It failed, there are no rightward entries.
1173 xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_NOERROR);
1177 * Loop going left with the leftward cursor, right with the
1178 * rightward cursor, until either both directions give up or
1179 * we find an entry at least as big as minlen.
1183 if ((error = xfs_alloc_get_rec(bno_cur_lt, <bno, <len, &i)))
1185 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1186 xfs_alloc_compute_aligned(args, ltbno, ltlen,
1188 if (ltlena >= args->minlen && ltbnoa >= args->min_agbno)
1190 if ((error = xfs_btree_decrement(bno_cur_lt, 0, &i)))
1192 if (!i || ltbnoa < args->min_agbno) {
1193 xfs_btree_del_cursor(bno_cur_lt,
1199 if ((error = xfs_alloc_get_rec(bno_cur_gt, >bno, >len, &i)))
1201 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1202 xfs_alloc_compute_aligned(args, gtbno, gtlen,
1204 if (gtlena >= args->minlen && gtbnoa <= args->max_agbno)
1206 if ((error = xfs_btree_increment(bno_cur_gt, 0, &i)))
1208 if (!i || gtbnoa > args->max_agbno) {
1209 xfs_btree_del_cursor(bno_cur_gt,
1214 } while (bno_cur_lt || bno_cur_gt);
1217 * Got both cursors still active, need to find better entry.
1219 if (bno_cur_lt && bno_cur_gt) {
1220 if (ltlena >= args->minlen) {
1222 * Left side is good, look for a right side entry.
1224 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
1225 xfs_alloc_fix_len(args);
1226 ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
1227 args->alignment, args->datatype, ltbnoa,
1230 error = xfs_alloc_find_best_extent(args,
1231 &bno_cur_lt, &bno_cur_gt,
1232 ltdiff, >bno, >len,
1234 0 /* search right */);
1236 ASSERT(gtlena >= args->minlen);
1239 * Right side is good, look for a left side entry.
1241 args->len = XFS_EXTLEN_MIN(gtlena, args->maxlen);
1242 xfs_alloc_fix_len(args);
1243 gtdiff = xfs_alloc_compute_diff(args->agbno, args->len,
1244 args->alignment, args->datatype, gtbnoa,
1247 error = xfs_alloc_find_best_extent(args,
1248 &bno_cur_gt, &bno_cur_lt,
1249 gtdiff, <bno, <len,
1251 1 /* search left */);
1259 * If we couldn't get anything, give up.
1261 if (bno_cur_lt == NULL && bno_cur_gt == NULL) {
1262 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1265 trace_xfs_alloc_near_busy(args);
1266 xfs_log_force(args->mp, XFS_LOG_SYNC);
1269 trace_xfs_alloc_size_neither(args);
1270 args->agbno = NULLAGBLOCK;
1275 * At this point we have selected a freespace entry, either to the
1276 * left or to the right. If it's on the right, copy all the
1277 * useful variables to the "left" set so we only have one
1278 * copy of this code.
1281 bno_cur_lt = bno_cur_gt;
1292 * Fix up the length and compute the useful address.
1294 args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
1295 xfs_alloc_fix_len(args);
1297 (void)xfs_alloc_compute_diff(args->agbno, rlen, args->alignment,
1298 args->datatype, ltbnoa, ltlena, <new);
1299 ASSERT(ltnew >= ltbno);
1300 ASSERT(ltnew + rlen <= ltbnoa + ltlena);
1301 ASSERT(ltnew + rlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
1302 ASSERT(ltnew >= args->min_agbno && ltnew <= args->max_agbno);
1303 args->agbno = ltnew;
1305 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno, ltlen,
1306 ltnew, rlen, XFSA_FIXUP_BNO_OK)))
1310 trace_xfs_alloc_near_greater(args);
1312 trace_xfs_alloc_near_lesser(args);
1314 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1315 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
1319 trace_xfs_alloc_near_error(args);
1320 if (cnt_cur != NULL)
1321 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1322 if (bno_cur_lt != NULL)
1323 xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_ERROR);
1324 if (bno_cur_gt != NULL)
1325 xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_ERROR);
1330 * Allocate a variable extent anywhere in the allocation group agno.
1331 * Extent's length (returned in len) will be between minlen and maxlen,
1332 * and of the form k * prod + mod unless there's nothing that large.
1333 * Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
1335 STATIC int /* error */
1336 xfs_alloc_ag_vextent_size(
1337 xfs_alloc_arg_t *args) /* allocation argument structure */
1339 xfs_btree_cur_t *bno_cur; /* cursor for bno btree */
1340 xfs_btree_cur_t *cnt_cur; /* cursor for cnt btree */
1341 int error; /* error result */
1342 xfs_agblock_t fbno; /* start of found freespace */
1343 xfs_extlen_t flen; /* length of found freespace */
1344 int i; /* temp status variable */
1345 xfs_agblock_t rbno; /* returned block number */
1346 xfs_extlen_t rlen; /* length of returned extent */
1351 * Allocate and initialize a cursor for the by-size btree.
1353 cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
1354 args->agno, XFS_BTNUM_CNT);
1358 * Look for an entry >= maxlen+alignment-1 blocks.
1360 if ((error = xfs_alloc_lookup_ge(cnt_cur, 0,
1361 args->maxlen + args->alignment - 1, &i)))
1365 * If none or we have busy extents that we cannot allocate from, then
1366 * we have to settle for a smaller extent. In the case that there are
1367 * no large extents, this will return the last entry in the tree unless
1368 * the tree is empty. In the case that there are only busy large
1369 * extents, this will return the largest small extent unless there
1370 * are no smaller extents available.
1372 if (!i || forced > 1) {
1373 error = xfs_alloc_ag_vextent_small(args, cnt_cur,
1377 if (i == 0 || flen == 0) {
1378 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1379 trace_xfs_alloc_size_noentry(args);
1383 xfs_alloc_compute_aligned(args, fbno, flen, &rbno, &rlen);
1386 * Search for a non-busy extent that is large enough.
1387 * If we are at low space, don't check, or if we fall of
1388 * the end of the btree, turn off the busy check and
1392 error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, &i);
1395 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1397 xfs_alloc_compute_aligned(args, fbno, flen,
1400 if (rlen >= args->maxlen)
1403 error = xfs_btree_increment(cnt_cur, 0, &i);
1408 * Our only valid extents must have been busy.
1409 * Make it unbusy by forcing the log out and
1410 * retrying. If we've been here before, forcing
1411 * the log isn't making the extents available,
1412 * which means they have probably been freed in
1413 * this transaction. In that case, we have to
1414 * give up on them and we'll attempt a minlen
1415 * allocation the next time around.
1417 xfs_btree_del_cursor(cnt_cur,
1419 trace_xfs_alloc_size_busy(args);
1421 xfs_log_force(args->mp, XFS_LOG_SYNC);
1428 * In the first case above, we got the last entry in the
1429 * by-size btree. Now we check to see if the space hits maxlen
1430 * once aligned; if not, we search left for something better.
1431 * This can't happen in the second case above.
1433 rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
1434 XFS_WANT_CORRUPTED_GOTO(args->mp, rlen == 0 ||
1435 (rlen <= flen && rbno + rlen <= fbno + flen), error0);
1436 if (rlen < args->maxlen) {
1437 xfs_agblock_t bestfbno;
1438 xfs_extlen_t bestflen;
1439 xfs_agblock_t bestrbno;
1440 xfs_extlen_t bestrlen;
1447 if ((error = xfs_btree_decrement(cnt_cur, 0, &i)))
1451 if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen,
1454 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1455 if (flen < bestrlen)
1457 xfs_alloc_compute_aligned(args, fbno, flen,
1459 rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
1460 XFS_WANT_CORRUPTED_GOTO(args->mp, rlen == 0 ||
1461 (rlen <= flen && rbno + rlen <= fbno + flen),
1463 if (rlen > bestrlen) {
1468 if (rlen == args->maxlen)
1472 if ((error = xfs_alloc_lookup_eq(cnt_cur, bestfbno, bestflen,
1475 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1481 args->wasfromfl = 0;
1483 * Fix up the length.
1486 if (rlen < args->minlen) {
1488 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1489 trace_xfs_alloc_size_busy(args);
1490 xfs_log_force(args->mp, XFS_LOG_SYNC);
1495 xfs_alloc_fix_len(args);
1498 XFS_WANT_CORRUPTED_GOTO(args->mp, rlen <= flen, error0);
1500 * Allocate and initialize a cursor for the by-block tree.
1502 bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
1503 args->agno, XFS_BTNUM_BNO);
1504 if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen,
1505 rbno, rlen, XFSA_FIXUP_CNT_OK)))
1507 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1508 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
1509 cnt_cur = bno_cur = NULL;
1512 XFS_WANT_CORRUPTED_GOTO(args->mp,
1513 args->agbno + args->len <=
1514 be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
1516 trace_xfs_alloc_size_done(args);
1520 trace_xfs_alloc_size_error(args);
1522 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1524 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
1528 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1529 trace_xfs_alloc_size_nominleft(args);
1530 args->agbno = NULLAGBLOCK;
1535 * Deal with the case where only small freespaces remain.
1536 * Either return the contents of the last freespace record,
1537 * or allocate space from the freelist if there is nothing in the tree.
1539 STATIC int /* error */
1540 xfs_alloc_ag_vextent_small(
1541 xfs_alloc_arg_t *args, /* allocation argument structure */
1542 xfs_btree_cur_t *ccur, /* by-size cursor */
1543 xfs_agblock_t *fbnop, /* result block number */
1544 xfs_extlen_t *flenp, /* result length */
1545 int *stat) /* status: 0-freelist, 1-normal/none */
1547 struct xfs_owner_info oinfo;
1548 struct xfs_perag *pag;
1554 if ((error = xfs_btree_decrement(ccur, 0, &i)))
1557 if ((error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i)))
1559 XFS_WANT_CORRUPTED_GOTO(args->mp, i == 1, error0);
1562 * Nothing in the btree, try the freelist. Make sure
1563 * to respect minleft even when pulling from the
1566 else if (args->minlen == 1 && args->alignment == 1 &&
1567 args->resv != XFS_AG_RESV_AGFL &&
1568 (be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount)
1570 error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0);
1573 if (fbno != NULLAGBLOCK) {
1574 xfs_extent_busy_reuse(args->mp, args->agno, fbno, 1,
1575 xfs_alloc_allow_busy_reuse(args->datatype));
1577 if (xfs_alloc_is_userdata(args->datatype)) {
1580 bp = xfs_btree_get_bufs(args->mp, args->tp,
1581 args->agno, fbno, 0);
1582 xfs_trans_binval(args->tp, bp);
1586 XFS_WANT_CORRUPTED_GOTO(args->mp,
1587 args->agbno + args->len <=
1588 be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
1590 args->wasfromfl = 1;
1591 trace_xfs_alloc_small_freelist(args);
1594 * If we're feeding an AGFL block to something that
1595 * doesn't live in the free space, we need to clear
1596 * out the OWN_AG rmap and add the block back to
1597 * the AGFL per-AG reservation.
1599 xfs_rmap_ag_owner(&oinfo, XFS_RMAP_OWN_AG);
1600 error = xfs_rmap_free(args->tp, args->agbp, args->agno,
1604 pag = xfs_perag_get(args->mp, args->agno);
1605 xfs_ag_resv_free_extent(pag, XFS_AG_RESV_AGFL,
1613 * Nothing in the freelist.
1619 * Can't allocate from the freelist for some reason.
1626 * Can't do the allocation, give up.
1628 if (flen < args->minlen) {
1629 args->agbno = NULLAGBLOCK;
1630 trace_xfs_alloc_small_notenough(args);
1636 trace_xfs_alloc_small_done(args);
1640 trace_xfs_alloc_small_error(args);
1645 * Free the extent starting at agno/bno for length.
1651 xfs_agnumber_t agno,
1654 struct xfs_owner_info *oinfo,
1655 enum xfs_ag_resv_type type)
1657 xfs_btree_cur_t *bno_cur; /* cursor for by-block btree */
1658 xfs_btree_cur_t *cnt_cur; /* cursor for by-size btree */
1659 int error; /* error return value */
1660 xfs_agblock_t gtbno; /* start of right neighbor block */
1661 xfs_extlen_t gtlen; /* length of right neighbor block */
1662 int haveleft; /* have a left neighbor block */
1663 int haveright; /* have a right neighbor block */
1664 int i; /* temp, result code */
1665 xfs_agblock_t ltbno; /* start of left neighbor block */
1666 xfs_extlen_t ltlen; /* length of left neighbor block */
1667 xfs_mount_t *mp; /* mount point struct for filesystem */
1668 xfs_agblock_t nbno; /* new starting block of freespace */
1669 xfs_extlen_t nlen; /* new length of freespace */
1670 xfs_perag_t *pag; /* per allocation group data */
1672 bno_cur = cnt_cur = NULL;
1675 if (oinfo->oi_owner != XFS_RMAP_OWN_UNKNOWN) {
1676 error = xfs_rmap_free(tp, agbp, agno, bno, len, oinfo);
1682 * Allocate and initialize a cursor for the by-block btree.
1684 bno_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_BNO);
1686 * Look for a neighboring block on the left (lower block numbers)
1687 * that is contiguous with this space.
1689 if ((error = xfs_alloc_lookup_le(bno_cur, bno, len, &haveleft)))
1693 * There is a block to our left.
1695 if ((error = xfs_alloc_get_rec(bno_cur, <bno, <len, &i)))
1697 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1699 * It's not contiguous, though.
1701 if (ltbno + ltlen < bno)
1705 * If this failure happens the request to free this
1706 * space was invalid, it's (partly) already free.
1709 XFS_WANT_CORRUPTED_GOTO(mp,
1710 ltbno + ltlen <= bno, error0);
1714 * Look for a neighboring block on the right (higher block numbers)
1715 * that is contiguous with this space.
1717 if ((error = xfs_btree_increment(bno_cur, 0, &haveright)))
1721 * There is a block to our right.
1723 if ((error = xfs_alloc_get_rec(bno_cur, >bno, >len, &i)))
1725 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1727 * It's not contiguous, though.
1729 if (bno + len < gtbno)
1733 * If this failure happens the request to free this
1734 * space was invalid, it's (partly) already free.
1737 XFS_WANT_CORRUPTED_GOTO(mp, gtbno >= bno + len, error0);
1741 * Now allocate and initialize a cursor for the by-size tree.
1743 cnt_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_CNT);
1745 * Have both left and right contiguous neighbors.
1746 * Merge all three into a single free block.
1748 if (haveleft && haveright) {
1750 * Delete the old by-size entry on the left.
1752 if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
1754 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1755 if ((error = xfs_btree_delete(cnt_cur, &i)))
1757 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1759 * Delete the old by-size entry on the right.
1761 if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
1763 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1764 if ((error = xfs_btree_delete(cnt_cur, &i)))
1766 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1768 * Delete the old by-block entry for the right block.
1770 if ((error = xfs_btree_delete(bno_cur, &i)))
1772 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1774 * Move the by-block cursor back to the left neighbor.
1776 if ((error = xfs_btree_decrement(bno_cur, 0, &i)))
1778 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1781 * Check that this is the right record: delete didn't
1782 * mangle the cursor.
1785 xfs_agblock_t xxbno;
1788 if ((error = xfs_alloc_get_rec(bno_cur, &xxbno, &xxlen,
1791 XFS_WANT_CORRUPTED_GOTO(mp,
1792 i == 1 && xxbno == ltbno && xxlen == ltlen,
1797 * Update remaining by-block entry to the new, joined block.
1800 nlen = len + ltlen + gtlen;
1801 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1805 * Have only a left contiguous neighbor.
1806 * Merge it together with the new freespace.
1808 else if (haveleft) {
1810 * Delete the old by-size entry on the left.
1812 if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
1814 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1815 if ((error = xfs_btree_delete(cnt_cur, &i)))
1817 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1819 * Back up the by-block cursor to the left neighbor, and
1820 * update its length.
1822 if ((error = xfs_btree_decrement(bno_cur, 0, &i)))
1824 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1827 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1831 * Have only a right contiguous neighbor.
1832 * Merge it together with the new freespace.
1834 else if (haveright) {
1836 * Delete the old by-size entry on the right.
1838 if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
1840 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1841 if ((error = xfs_btree_delete(cnt_cur, &i)))
1843 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1845 * Update the starting block and length of the right
1846 * neighbor in the by-block tree.
1850 if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
1854 * No contiguous neighbors.
1855 * Insert the new freespace into the by-block tree.
1860 if ((error = xfs_btree_insert(bno_cur, &i)))
1862 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1864 xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
1867 * In all cases we need to insert the new freespace in the by-size tree.
1869 if ((error = xfs_alloc_lookup_eq(cnt_cur, nbno, nlen, &i)))
1871 XFS_WANT_CORRUPTED_GOTO(mp, i == 0, error0);
1872 if ((error = xfs_btree_insert(cnt_cur, &i)))
1874 XFS_WANT_CORRUPTED_GOTO(mp, i == 1, error0);
1875 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
1879 * Update the freespace totals in the ag and superblock.
1881 pag = xfs_perag_get(mp, agno);
1882 error = xfs_alloc_update_counters(tp, pag, agbp, len);
1883 xfs_ag_resv_free_extent(pag, type, tp, len);
1888 XFS_STATS_INC(mp, xs_freex);
1889 XFS_STATS_ADD(mp, xs_freeb, len);
1891 trace_xfs_free_extent(mp, agno, bno, len, type == XFS_AG_RESV_AGFL,
1892 haveleft, haveright);
1897 trace_xfs_free_extent(mp, agno, bno, len, type == XFS_AG_RESV_AGFL,
1900 xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
1902 xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
1907 * Visible (exported) allocation/free functions.
1908 * Some of these are used just by xfs_alloc_btree.c and this file.
1912 * Compute and fill in value of m_ag_maxlevels.
1915 xfs_alloc_compute_maxlevels(
1916 xfs_mount_t *mp) /* file system mount structure */
1918 mp->m_ag_maxlevels = xfs_btree_compute_maxlevels(mp, mp->m_alloc_mnr,
1919 (mp->m_sb.sb_agblocks + 1) / 2);
1923 * Find the length of the longest extent in an AG. The 'need' parameter
1924 * specifies how much space we're going to need for the AGFL and the
1925 * 'reserved' parameter tells us how many blocks in this AG are reserved for
1929 xfs_alloc_longest_free_extent(
1930 struct xfs_mount *mp,
1931 struct xfs_perag *pag,
1933 xfs_extlen_t reserved)
1935 xfs_extlen_t delta = 0;
1938 * If the AGFL needs a recharge, we'll have to subtract that from the
1941 if (need > pag->pagf_flcount)
1942 delta = need - pag->pagf_flcount;
1945 * If we cannot maintain others' reservations with space from the
1946 * not-longest freesp extents, we'll have to subtract /that/ from
1947 * the longest extent too.
1949 if (pag->pagf_freeblks - pag->pagf_longest < reserved)
1950 delta += reserved - (pag->pagf_freeblks - pag->pagf_longest);
1953 * If the longest extent is long enough to satisfy all the
1954 * reservations and AGFL rules in place, we can return this extent.
1956 if (pag->pagf_longest > delta)
1957 return pag->pagf_longest - delta;
1959 /* Otherwise, let the caller try for 1 block if there's space. */
1960 return pag->pagf_flcount > 0 || pag->pagf_longest > 0;
1964 xfs_alloc_min_freelist(
1965 struct xfs_mount *mp,
1966 struct xfs_perag *pag)
1968 unsigned int min_free;
1970 /* space needed by-bno freespace btree */
1971 min_free = min_t(unsigned int, pag->pagf_levels[XFS_BTNUM_BNOi] + 1,
1972 mp->m_ag_maxlevels);
1973 /* space needed by-size freespace btree */
1974 min_free += min_t(unsigned int, pag->pagf_levels[XFS_BTNUM_CNTi] + 1,
1975 mp->m_ag_maxlevels);
1976 /* space needed reverse mapping used space btree */
1977 if (xfs_sb_version_hasrmapbt(&mp->m_sb))
1978 min_free += min_t(unsigned int,
1979 pag->pagf_levels[XFS_BTNUM_RMAPi] + 1,
1980 mp->m_rmap_maxlevels);
1986 * Check if the operation we are fixing up the freelist for should go ahead or
1987 * not. If we are freeing blocks, we always allow it, otherwise the allocation
1988 * is dependent on whether the size and shape of free space available will
1989 * permit the requested allocation to take place.
1992 xfs_alloc_space_available(
1993 struct xfs_alloc_arg *args,
1994 xfs_extlen_t min_free,
1997 struct xfs_perag *pag = args->pag;
1998 xfs_extlen_t alloc_len, longest;
1999 xfs_extlen_t reservation; /* blocks that are still reserved */
2002 if (flags & XFS_ALLOC_FLAG_FREEING)
2005 reservation = xfs_ag_resv_needed(pag, args->resv);
2007 /* do we have enough contiguous free space for the allocation? */
2008 alloc_len = args->minlen + (args->alignment - 1) + args->minalignslop;
2009 longest = xfs_alloc_longest_free_extent(args->mp, pag, min_free,
2011 if (longest < alloc_len)
2014 /* do we have enough free space remaining for the allocation? */
2015 available = (int)(pag->pagf_freeblks + pag->pagf_flcount -
2016 reservation - min_free - args->minleft);
2017 if (available < (int)max(args->total, alloc_len))
2021 * Clamp maxlen to the amount of free space available for the actual
2022 * extent allocation.
2024 if (available < (int)args->maxlen && !(flags & XFS_ALLOC_FLAG_CHECK)) {
2025 args->maxlen = available;
2026 ASSERT(args->maxlen > 0);
2027 ASSERT(args->maxlen >= args->minlen);
2034 * Decide whether to use this allocation group for this allocation.
2035 * If so, fix up the btree freelist's size.
2038 xfs_alloc_fix_freelist(
2039 struct xfs_alloc_arg *args, /* allocation argument structure */
2040 int flags) /* XFS_ALLOC_FLAG_... */
2042 struct xfs_mount *mp = args->mp;
2043 struct xfs_perag *pag = args->pag;
2044 struct xfs_trans *tp = args->tp;
2045 struct xfs_buf *agbp = NULL;
2046 struct xfs_buf *agflbp = NULL;
2047 struct xfs_alloc_arg targs; /* local allocation arguments */
2048 xfs_agblock_t bno; /* freelist block */
2049 xfs_extlen_t need; /* total blocks needed in freelist */
2052 if (!pag->pagf_init) {
2053 error = xfs_alloc_read_agf(mp, tp, args->agno, flags, &agbp);
2056 if (!pag->pagf_init) {
2057 ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK);
2058 ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
2059 goto out_agbp_relse;
2064 * If this is a metadata preferred pag and we are user data then try
2065 * somewhere else if we are not being asked to try harder at this
2068 if (pag->pagf_metadata && xfs_alloc_is_userdata(args->datatype) &&
2069 (flags & XFS_ALLOC_FLAG_TRYLOCK)) {
2070 ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
2071 goto out_agbp_relse;
2074 need = xfs_alloc_min_freelist(mp, pag);
2075 if (!xfs_alloc_space_available(args, need, flags |
2076 XFS_ALLOC_FLAG_CHECK))
2077 goto out_agbp_relse;
2080 * Get the a.g. freespace buffer.
2081 * Can fail if we're not blocking on locks, and it's held.
2084 error = xfs_alloc_read_agf(mp, tp, args->agno, flags, &agbp);
2088 ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK);
2089 ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
2094 /* If there isn't enough total space or single-extent, reject it. */
2095 need = xfs_alloc_min_freelist(mp, pag);
2096 if (!xfs_alloc_space_available(args, need, flags))
2097 goto out_agbp_relse;
2100 * Make the freelist shorter if it's too long.
2102 * Note that from this point onwards, we will always release the agf and
2103 * agfl buffers on error. This handles the case where we error out and
2104 * the buffers are clean or may not have been joined to the transaction
2105 * and hence need to be released manually. If they have been joined to
2106 * the transaction, then xfs_trans_brelse() will handle them
2107 * appropriately based on the recursion count and dirty state of the
2110 * XXX (dgc): When we have lots of free space, does this buy us
2111 * anything other than extra overhead when we need to put more blocks
2112 * back on the free list? Maybe we should only do this when space is
2113 * getting low or the AGFL is more than half full?
2115 * The NOSHRINK flag prevents the AGFL from being shrunk if it's too
2116 * big; the NORMAP flag prevents AGFL expand/shrink operations from
2117 * updating the rmapbt. Both flags are used in xfs_repair while we're
2118 * rebuilding the rmapbt, and neither are used by the kernel. They're
2119 * both required to ensure that rmaps are correctly recorded for the
2120 * regenerated AGFL, bnobt, and cntbt. See repair/phase5.c and
2121 * repair/rmap.c in xfsprogs for details.
2123 memset(&targs, 0, sizeof(targs));
2124 if (flags & XFS_ALLOC_FLAG_NORMAP)
2125 xfs_rmap_skip_owner_update(&targs.oinfo);
2127 xfs_rmap_ag_owner(&targs.oinfo, XFS_RMAP_OWN_AG);
2128 while (!(flags & XFS_ALLOC_FLAG_NOSHRINK) && pag->pagf_flcount > need) {
2131 error = xfs_alloc_get_freelist(tp, agbp, &bno, 0);
2133 goto out_agbp_relse;
2134 error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1,
2135 &targs.oinfo, XFS_AG_RESV_AGFL);
2137 goto out_agbp_relse;
2138 bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0);
2139 xfs_trans_binval(tp, bp);
2145 targs.agno = args->agno;
2146 targs.alignment = targs.minlen = targs.prod = 1;
2147 targs.type = XFS_ALLOCTYPE_THIS_AG;
2149 error = xfs_alloc_read_agfl(mp, tp, targs.agno, &agflbp);
2151 goto out_agbp_relse;
2153 /* Make the freelist longer if it's too short. */
2154 while (pag->pagf_flcount < need) {
2156 targs.maxlen = need - pag->pagf_flcount;
2157 targs.resv = XFS_AG_RESV_AGFL;
2159 /* Allocate as many blocks as possible at once. */
2160 error = xfs_alloc_ag_vextent(&targs);
2162 goto out_agflbp_relse;
2165 * Stop if we run out. Won't happen if callers are obeying
2166 * the restrictions correctly. Can happen for free calls
2167 * on a completely full ag.
2169 if (targs.agbno == NULLAGBLOCK) {
2170 if (flags & XFS_ALLOC_FLAG_FREEING)
2172 goto out_agflbp_relse;
2175 * Put each allocated block on the list.
2177 for (bno = targs.agbno; bno < targs.agbno + targs.len; bno++) {
2178 error = xfs_alloc_put_freelist(tp, agbp,
2181 goto out_agflbp_relse;
2184 xfs_trans_brelse(tp, agflbp);
2189 xfs_trans_brelse(tp, agflbp);
2192 xfs_trans_brelse(tp, agbp);
2199 * Get a block from the freelist.
2200 * Returns with the buffer for the block gotten.
2203 xfs_alloc_get_freelist(
2204 xfs_trans_t *tp, /* transaction pointer */
2205 xfs_buf_t *agbp, /* buffer containing the agf structure */
2206 xfs_agblock_t *bnop, /* block address retrieved from freelist */
2207 int btreeblk) /* destination is a AGF btree */
2209 xfs_agf_t *agf; /* a.g. freespace structure */
2210 xfs_buf_t *agflbp;/* buffer for a.g. freelist structure */
2211 xfs_agblock_t bno; /* block number returned */
2215 xfs_mount_t *mp = tp->t_mountp;
2216 xfs_perag_t *pag; /* per allocation group data */
2219 * Freelist is empty, give up.
2221 agf = XFS_BUF_TO_AGF(agbp);
2222 if (!agf->agf_flcount) {
2223 *bnop = NULLAGBLOCK;
2227 * Read the array of free blocks.
2229 error = xfs_alloc_read_agfl(mp, tp, be32_to_cpu(agf->agf_seqno),
2236 * Get the block number and update the data structures.
2238 agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, agflbp);
2239 bno = be32_to_cpu(agfl_bno[be32_to_cpu(agf->agf_flfirst)]);
2240 be32_add_cpu(&agf->agf_flfirst, 1);
2241 xfs_trans_brelse(tp, agflbp);
2242 if (be32_to_cpu(agf->agf_flfirst) == XFS_AGFL_SIZE(mp))
2243 agf->agf_flfirst = 0;
2245 pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
2246 be32_add_cpu(&agf->agf_flcount, -1);
2247 xfs_trans_agflist_delta(tp, -1);
2248 pag->pagf_flcount--;
2251 logflags = XFS_AGF_FLFIRST | XFS_AGF_FLCOUNT;
2253 be32_add_cpu(&agf->agf_btreeblks, 1);
2254 pag->pagf_btreeblks++;
2255 logflags |= XFS_AGF_BTREEBLKS;
2258 xfs_alloc_log_agf(tp, agbp, logflags);
2265 * Log the given fields from the agf structure.
2269 xfs_trans_t *tp, /* transaction pointer */
2270 xfs_buf_t *bp, /* buffer for a.g. freelist header */
2271 int fields) /* mask of fields to be logged (XFS_AGF_...) */
2273 int first; /* first byte offset */
2274 int last; /* last byte offset */
2275 static const short offsets[] = {
2276 offsetof(xfs_agf_t, agf_magicnum),
2277 offsetof(xfs_agf_t, agf_versionnum),
2278 offsetof(xfs_agf_t, agf_seqno),
2279 offsetof(xfs_agf_t, agf_length),
2280 offsetof(xfs_agf_t, agf_roots[0]),
2281 offsetof(xfs_agf_t, agf_levels[0]),
2282 offsetof(xfs_agf_t, agf_flfirst),
2283 offsetof(xfs_agf_t, agf_fllast),
2284 offsetof(xfs_agf_t, agf_flcount),
2285 offsetof(xfs_agf_t, agf_freeblks),
2286 offsetof(xfs_agf_t, agf_longest),
2287 offsetof(xfs_agf_t, agf_btreeblks),
2288 offsetof(xfs_agf_t, agf_uuid),
2289 offsetof(xfs_agf_t, agf_rmap_blocks),
2290 offsetof(xfs_agf_t, agf_refcount_blocks),
2291 offsetof(xfs_agf_t, agf_refcount_root),
2292 offsetof(xfs_agf_t, agf_refcount_level),
2293 /* needed so that we don't log the whole rest of the structure: */
2294 offsetof(xfs_agf_t, agf_spare64),
2298 trace_xfs_agf(tp->t_mountp, XFS_BUF_TO_AGF(bp), fields, _RET_IP_);
2300 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_AGF_BUF);
2302 xfs_btree_offsets(fields, offsets, XFS_AGF_NUM_BITS, &first, &last);
2303 xfs_trans_log_buf(tp, bp, (uint)first, (uint)last);
2307 * Interface for inode allocation to force the pag data to be initialized.
2310 xfs_alloc_pagf_init(
2311 xfs_mount_t *mp, /* file system mount structure */
2312 xfs_trans_t *tp, /* transaction pointer */
2313 xfs_agnumber_t agno, /* allocation group number */
2314 int flags) /* XFS_ALLOC_FLAGS_... */
2319 if ((error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp)))
2322 xfs_trans_brelse(tp, bp);
2327 * Put the block on the freelist for the allocation group.
2330 xfs_alloc_put_freelist(
2331 xfs_trans_t *tp, /* transaction pointer */
2332 xfs_buf_t *agbp, /* buffer for a.g. freelist header */
2333 xfs_buf_t *agflbp,/* buffer for a.g. free block array */
2334 xfs_agblock_t bno, /* block being freed */
2335 int btreeblk) /* block came from a AGF btree */
2337 xfs_agf_t *agf; /* a.g. freespace structure */
2338 __be32 *blockp;/* pointer to array entry */
2341 xfs_mount_t *mp; /* mount structure */
2342 xfs_perag_t *pag; /* per allocation group data */
2346 agf = XFS_BUF_TO_AGF(agbp);
2349 if (!agflbp && (error = xfs_alloc_read_agfl(mp, tp,
2350 be32_to_cpu(agf->agf_seqno), &agflbp)))
2352 be32_add_cpu(&agf->agf_fllast, 1);
2353 if (be32_to_cpu(agf->agf_fllast) == XFS_AGFL_SIZE(mp))
2354 agf->agf_fllast = 0;
2356 pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
2357 be32_add_cpu(&agf->agf_flcount, 1);
2358 xfs_trans_agflist_delta(tp, 1);
2359 pag->pagf_flcount++;
2361 logflags = XFS_AGF_FLLAST | XFS_AGF_FLCOUNT;
2363 be32_add_cpu(&agf->agf_btreeblks, -1);
2364 pag->pagf_btreeblks--;
2365 logflags |= XFS_AGF_BTREEBLKS;
2369 xfs_alloc_log_agf(tp, agbp, logflags);
2371 ASSERT(be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp));
2373 agfl_bno = XFS_BUF_TO_AGFL_BNO(mp, agflbp);
2374 blockp = &agfl_bno[be32_to_cpu(agf->agf_fllast)];
2375 *blockp = cpu_to_be32(bno);
2376 startoff = (char *)blockp - (char *)agflbp->b_addr;
2378 xfs_alloc_log_agf(tp, agbp, logflags);
2380 xfs_trans_buf_set_type(tp, agflbp, XFS_BLFT_AGFL_BUF);
2381 xfs_trans_log_buf(tp, agflbp, startoff,
2382 startoff + sizeof(xfs_agblock_t) - 1);
2388 struct xfs_mount *mp,
2391 struct xfs_agf *agf = XFS_BUF_TO_AGF(bp);
2393 if (xfs_sb_version_hascrc(&mp->m_sb)) {
2394 if (!uuid_equal(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid))
2396 if (!xfs_log_check_lsn(mp,
2397 be64_to_cpu(XFS_BUF_TO_AGF(bp)->agf_lsn)))
2401 if (!(agf->agf_magicnum == cpu_to_be32(XFS_AGF_MAGIC) &&
2402 XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) &&
2403 be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) &&
2404 be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) &&
2405 be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) &&
2406 be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp)))
2409 if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 ||
2410 be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 ||
2411 be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||
2412 be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) > XFS_BTREE_MAXLEVELS)
2415 if (xfs_sb_version_hasrmapbt(&mp->m_sb) &&
2416 (be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) < 1 ||
2417 be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS))
2421 * during growfs operations, the perag is not fully initialised,
2422 * so we can't use it for any useful checking. growfs ensures we can't
2423 * use it by using uncached buffers that don't have the perag attached
2424 * so we can detect and avoid this problem.
2426 if (bp->b_pag && be32_to_cpu(agf->agf_seqno) != bp->b_pag->pag_agno)
2429 if (xfs_sb_version_haslazysbcount(&mp->m_sb) &&
2430 be32_to_cpu(agf->agf_btreeblks) > be32_to_cpu(agf->agf_length))
2433 if (xfs_sb_version_hasreflink(&mp->m_sb) &&
2434 (be32_to_cpu(agf->agf_refcount_level) < 1 ||
2435 be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS))
2443 xfs_agf_read_verify(
2446 struct xfs_mount *mp = bp->b_target->bt_mount;
2448 if (xfs_sb_version_hascrc(&mp->m_sb) &&
2449 !xfs_buf_verify_cksum(bp, XFS_AGF_CRC_OFF))
2450 xfs_buf_ioerror(bp, -EFSBADCRC);
2451 else if (XFS_TEST_ERROR(!xfs_agf_verify(mp, bp), mp,
2452 XFS_ERRTAG_ALLOC_READ_AGF,
2453 XFS_RANDOM_ALLOC_READ_AGF))
2454 xfs_buf_ioerror(bp, -EFSCORRUPTED);
2457 xfs_verifier_error(bp);
2461 xfs_agf_write_verify(
2464 struct xfs_mount *mp = bp->b_target->bt_mount;
2465 struct xfs_buf_log_item *bip = bp->b_fspriv;
2467 if (!xfs_agf_verify(mp, bp)) {
2468 xfs_buf_ioerror(bp, -EFSCORRUPTED);
2469 xfs_verifier_error(bp);
2473 if (!xfs_sb_version_hascrc(&mp->m_sb))
2477 XFS_BUF_TO_AGF(bp)->agf_lsn = cpu_to_be64(bip->bli_item.li_lsn);
2479 xfs_buf_update_cksum(bp, XFS_AGF_CRC_OFF);
2482 const struct xfs_buf_ops xfs_agf_buf_ops = {
2484 .verify_read = xfs_agf_read_verify,
2485 .verify_write = xfs_agf_write_verify,
2489 * Read in the allocation group header (free/alloc section).
2493 struct xfs_mount *mp, /* mount point structure */
2494 struct xfs_trans *tp, /* transaction pointer */
2495 xfs_agnumber_t agno, /* allocation group number */
2496 int flags, /* XFS_BUF_ */
2497 struct xfs_buf **bpp) /* buffer for the ag freelist header */
2501 trace_xfs_read_agf(mp, agno);
2503 ASSERT(agno != NULLAGNUMBER);
2504 error = xfs_trans_read_buf(
2505 mp, tp, mp->m_ddev_targp,
2506 XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
2507 XFS_FSS_TO_BB(mp, 1), flags, bpp, &xfs_agf_buf_ops);
2513 ASSERT(!(*bpp)->b_error);
2514 xfs_buf_set_ref(*bpp, XFS_AGF_REF);
2519 * Read in the allocation group header (free/alloc section).
2523 struct xfs_mount *mp, /* mount point structure */
2524 struct xfs_trans *tp, /* transaction pointer */
2525 xfs_agnumber_t agno, /* allocation group number */
2526 int flags, /* XFS_ALLOC_FLAG_... */
2527 struct xfs_buf **bpp) /* buffer for the ag freelist header */
2529 struct xfs_agf *agf; /* ag freelist header */
2530 struct xfs_perag *pag; /* per allocation group data */
2533 trace_xfs_alloc_read_agf(mp, agno);
2535 ASSERT(agno != NULLAGNUMBER);
2536 error = xfs_read_agf(mp, tp, agno,
2537 (flags & XFS_ALLOC_FLAG_TRYLOCK) ? XBF_TRYLOCK : 0,
2543 ASSERT(!(*bpp)->b_error);
2545 agf = XFS_BUF_TO_AGF(*bpp);
2546 pag = xfs_perag_get(mp, agno);
2547 if (!pag->pagf_init) {
2548 pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
2549 pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks);
2550 pag->pagf_flcount = be32_to_cpu(agf->agf_flcount);
2551 pag->pagf_longest = be32_to_cpu(agf->agf_longest);
2552 pag->pagf_levels[XFS_BTNUM_BNOi] =
2553 be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]);
2554 pag->pagf_levels[XFS_BTNUM_CNTi] =
2555 be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]);
2556 pag->pagf_levels[XFS_BTNUM_RMAPi] =
2557 be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAPi]);
2558 pag->pagf_refcount_level = be32_to_cpu(agf->agf_refcount_level);
2559 spin_lock_init(&pag->pagb_lock);
2560 pag->pagb_count = 0;
2561 pag->pagb_tree = RB_ROOT;
2565 else if (!XFS_FORCED_SHUTDOWN(mp)) {
2566 ASSERT(pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks));
2567 ASSERT(pag->pagf_btreeblks == be32_to_cpu(agf->agf_btreeblks));
2568 ASSERT(pag->pagf_flcount == be32_to_cpu(agf->agf_flcount));
2569 ASSERT(pag->pagf_longest == be32_to_cpu(agf->agf_longest));
2570 ASSERT(pag->pagf_levels[XFS_BTNUM_BNOi] ==
2571 be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]));
2572 ASSERT(pag->pagf_levels[XFS_BTNUM_CNTi] ==
2573 be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]));
2581 * Allocate an extent (variable-size).
2582 * Depending on the allocation type, we either look in a single allocation
2583 * group or loop over the allocation groups to find the result.
2587 xfs_alloc_arg_t *args) /* allocation argument structure */
2589 xfs_agblock_t agsize; /* allocation group size */
2591 int flags; /* XFS_ALLOC_FLAG_... locking flags */
2592 xfs_mount_t *mp; /* mount structure pointer */
2593 xfs_agnumber_t sagno; /* starting allocation group number */
2594 xfs_alloctype_t type; /* input allocation type */
2596 xfs_agnumber_t rotorstep = xfs_rotorstep; /* inode32 agf stepper */
2599 type = args->otype = args->type;
2600 args->agbno = NULLAGBLOCK;
2602 * Just fix this up, for the case where the last a.g. is shorter
2603 * (or there's only one a.g.) and the caller couldn't easily figure
2604 * that out (xfs_bmap_alloc).
2606 agsize = mp->m_sb.sb_agblocks;
2607 if (args->maxlen > agsize)
2608 args->maxlen = agsize;
2609 if (args->alignment == 0)
2610 args->alignment = 1;
2611 ASSERT(XFS_FSB_TO_AGNO(mp, args->fsbno) < mp->m_sb.sb_agcount);
2612 ASSERT(XFS_FSB_TO_AGBNO(mp, args->fsbno) < agsize);
2613 ASSERT(args->minlen <= args->maxlen);
2614 ASSERT(args->minlen <= agsize);
2615 ASSERT(args->mod < args->prod);
2616 if (XFS_FSB_TO_AGNO(mp, args->fsbno) >= mp->m_sb.sb_agcount ||
2617 XFS_FSB_TO_AGBNO(mp, args->fsbno) >= agsize ||
2618 args->minlen > args->maxlen || args->minlen > agsize ||
2619 args->mod >= args->prod) {
2620 args->fsbno = NULLFSBLOCK;
2621 trace_xfs_alloc_vextent_badargs(args);
2626 case XFS_ALLOCTYPE_THIS_AG:
2627 case XFS_ALLOCTYPE_NEAR_BNO:
2628 case XFS_ALLOCTYPE_THIS_BNO:
2630 * These three force us into a single a.g.
2632 args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2633 args->pag = xfs_perag_get(mp, args->agno);
2634 error = xfs_alloc_fix_freelist(args, 0);
2636 trace_xfs_alloc_vextent_nofix(args);
2640 trace_xfs_alloc_vextent_noagbp(args);
2643 args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
2644 if ((error = xfs_alloc_ag_vextent(args)))
2647 case XFS_ALLOCTYPE_START_BNO:
2649 * Try near allocation first, then anywhere-in-ag after
2650 * the first a.g. fails.
2652 if ((args->datatype & XFS_ALLOC_INITIAL_USER_DATA) &&
2653 (mp->m_flags & XFS_MOUNT_32BITINODES)) {
2654 args->fsbno = XFS_AGB_TO_FSB(mp,
2655 ((mp->m_agfrotor / rotorstep) %
2656 mp->m_sb.sb_agcount), 0);
2659 args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
2660 args->type = XFS_ALLOCTYPE_NEAR_BNO;
2662 case XFS_ALLOCTYPE_ANY_AG:
2663 case XFS_ALLOCTYPE_START_AG:
2664 case XFS_ALLOCTYPE_FIRST_AG:
2666 * Rotate through the allocation groups looking for a winner.
2668 if (type == XFS_ALLOCTYPE_ANY_AG) {
2670 * Start with the last place we left off.
2672 args->agno = sagno = (mp->m_agfrotor / rotorstep) %
2673 mp->m_sb.sb_agcount;
2674 args->type = XFS_ALLOCTYPE_THIS_AG;
2675 flags = XFS_ALLOC_FLAG_TRYLOCK;
2676 } else if (type == XFS_ALLOCTYPE_FIRST_AG) {
2678 * Start with allocation group given by bno.
2680 args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2681 args->type = XFS_ALLOCTYPE_THIS_AG;
2685 if (type == XFS_ALLOCTYPE_START_AG)
2686 args->type = XFS_ALLOCTYPE_THIS_AG;
2688 * Start with the given allocation group.
2690 args->agno = sagno = XFS_FSB_TO_AGNO(mp, args->fsbno);
2691 flags = XFS_ALLOC_FLAG_TRYLOCK;
2694 * Loop over allocation groups twice; first time with
2695 * trylock set, second time without.
2698 args->pag = xfs_perag_get(mp, args->agno);
2699 error = xfs_alloc_fix_freelist(args, flags);
2701 trace_xfs_alloc_vextent_nofix(args);
2705 * If we get a buffer back then the allocation will fly.
2708 if ((error = xfs_alloc_ag_vextent(args)))
2713 trace_xfs_alloc_vextent_loopfailed(args);
2716 * Didn't work, figure out the next iteration.
2718 if (args->agno == sagno &&
2719 type == XFS_ALLOCTYPE_START_BNO)
2720 args->type = XFS_ALLOCTYPE_THIS_AG;
2722 * For the first allocation, we can try any AG to get
2723 * space. However, if we already have allocated a
2724 * block, we don't want to try AGs whose number is below
2725 * sagno. Otherwise, we may end up with out-of-order
2726 * locking of AGF, which might cause deadlock.
2728 if (++(args->agno) == mp->m_sb.sb_agcount) {
2729 if (args->firstblock != NULLFSBLOCK)
2735 * Reached the starting a.g., must either be done
2736 * or switch to non-trylock mode.
2738 if (args->agno == sagno) {
2740 args->agbno = NULLAGBLOCK;
2741 trace_xfs_alloc_vextent_allfailed(args);
2746 if (type == XFS_ALLOCTYPE_START_BNO) {
2747 args->agbno = XFS_FSB_TO_AGBNO(mp,
2749 args->type = XFS_ALLOCTYPE_NEAR_BNO;
2752 xfs_perag_put(args->pag);
2754 if (bump_rotor || (type == XFS_ALLOCTYPE_ANY_AG)) {
2755 if (args->agno == sagno)
2756 mp->m_agfrotor = (mp->m_agfrotor + 1) %
2757 (mp->m_sb.sb_agcount * rotorstep);
2759 mp->m_agfrotor = (args->agno * rotorstep + 1) %
2760 (mp->m_sb.sb_agcount * rotorstep);
2767 if (args->agbno == NULLAGBLOCK)
2768 args->fsbno = NULLFSBLOCK;
2770 args->fsbno = XFS_AGB_TO_FSB(mp, args->agno, args->agbno);
2772 ASSERT(args->len >= args->minlen);
2773 ASSERT(args->len <= args->maxlen);
2774 ASSERT(args->agbno % args->alignment == 0);
2775 XFS_AG_CHECK_DADDR(mp, XFS_FSB_TO_DADDR(mp, args->fsbno),
2779 /* Zero the extent if we were asked to do so */
2780 if (args->datatype & XFS_ALLOC_USERDATA_ZERO) {
2781 error = xfs_zero_extent(args->ip, args->fsbno, args->len);
2787 xfs_perag_put(args->pag);
2790 xfs_perag_put(args->pag);
2794 /* Ensure that the freelist is at full capacity. */
2796 xfs_free_extent_fix_freelist(
2797 struct xfs_trans *tp,
2798 xfs_agnumber_t agno,
2799 struct xfs_buf **agbp)
2801 struct xfs_alloc_arg args;
2804 memset(&args, 0, sizeof(struct xfs_alloc_arg));
2806 args.mp = tp->t_mountp;
2810 * validate that the block number is legal - the enables us to detect
2811 * and handle a silent filesystem corruption rather than crashing.
2813 if (args.agno >= args.mp->m_sb.sb_agcount)
2814 return -EFSCORRUPTED;
2816 args.pag = xfs_perag_get(args.mp, args.agno);
2819 error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
2825 xfs_perag_put(args.pag);
2831 * Just break up the extent address and hand off to xfs_free_ag_extent
2832 * after fixing up the freelist.
2836 struct xfs_trans *tp, /* transaction pointer */
2837 xfs_fsblock_t bno, /* starting block number of extent */
2838 xfs_extlen_t len, /* length of extent */
2839 struct xfs_owner_info *oinfo, /* extent owner */
2840 enum xfs_ag_resv_type type) /* block reservation type */
2842 struct xfs_mount *mp = tp->t_mountp;
2843 struct xfs_buf *agbp;
2844 xfs_agnumber_t agno = XFS_FSB_TO_AGNO(mp, bno);
2845 xfs_agblock_t agbno = XFS_FSB_TO_AGBNO(mp, bno);
2849 ASSERT(type != XFS_AG_RESV_AGFL);
2851 if (XFS_TEST_ERROR(false, mp,
2852 XFS_ERRTAG_FREE_EXTENT,
2853 XFS_RANDOM_FREE_EXTENT))
2856 error = xfs_free_extent_fix_freelist(tp, agno, &agbp);
2860 XFS_WANT_CORRUPTED_GOTO(mp, agbno < mp->m_sb.sb_agblocks, err);
2862 /* validate the extent size is legal now we have the agf locked */
2863 XFS_WANT_CORRUPTED_GOTO(mp,
2864 agbno + len <= be32_to_cpu(XFS_BUF_TO_AGF(agbp)->agf_length),
2867 error = xfs_free_ag_extent(tp, agbp, agno, agbno, len, oinfo, type);
2871 xfs_extent_busy_insert(tp, agno, agbno, len, 0);
2875 xfs_trans_brelse(tp, agbp);