mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Dave Chinner](/assets/img/avatar_default.png)
A fuzzed filesystem crashed a kernel when freeing an extent with a block number beyond the end of the filesystem. Convert all the debug asserts in xfs_free_extent() to active checks so that we catch bad extents and return that the filesytsem is corrupted rather than crashing. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Alex Elder <aelder@sgi.com>
2698 lines
76 KiB
C
2698 lines
76 KiB
C
/*
|
|
* Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
|
|
* All Rights Reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it would be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write the Free Software Foundation,
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
#include "xfs.h"
|
|
#include "xfs_fs.h"
|
|
#include "xfs_types.h"
|
|
#include "xfs_bit.h"
|
|
#include "xfs_log.h"
|
|
#include "xfs_inum.h"
|
|
#include "xfs_trans.h"
|
|
#include "xfs_sb.h"
|
|
#include "xfs_ag.h"
|
|
#include "xfs_mount.h"
|
|
#include "xfs_bmap_btree.h"
|
|
#include "xfs_alloc_btree.h"
|
|
#include "xfs_ialloc_btree.h"
|
|
#include "xfs_dinode.h"
|
|
#include "xfs_inode.h"
|
|
#include "xfs_btree.h"
|
|
#include "xfs_alloc.h"
|
|
#include "xfs_error.h"
|
|
#include "xfs_trace.h"
|
|
|
|
|
|
#define XFS_ABSDIFF(a,b) (((a) <= (b)) ? ((b) - (a)) : ((a) - (b)))
|
|
|
|
#define XFSA_FIXUP_BNO_OK 1
|
|
#define XFSA_FIXUP_CNT_OK 2
|
|
|
|
/*
|
|
* Prototypes for per-ag allocation routines
|
|
*/
|
|
|
|
STATIC int xfs_alloc_ag_vextent_exact(xfs_alloc_arg_t *);
|
|
STATIC int xfs_alloc_ag_vextent_near(xfs_alloc_arg_t *);
|
|
STATIC int xfs_alloc_ag_vextent_size(xfs_alloc_arg_t *);
|
|
STATIC int xfs_alloc_ag_vextent_small(xfs_alloc_arg_t *,
|
|
xfs_btree_cur_t *, xfs_agblock_t *, xfs_extlen_t *, int *);
|
|
|
|
/*
|
|
* Internal functions.
|
|
*/
|
|
|
|
/*
|
|
* Lookup the record equal to [bno, len] in the btree given by cur.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_lookup_eq(
|
|
struct xfs_btree_cur *cur, /* btree cursor */
|
|
xfs_agblock_t bno, /* starting block of extent */
|
|
xfs_extlen_t len, /* length of extent */
|
|
int *stat) /* success/failure */
|
|
{
|
|
cur->bc_rec.a.ar_startblock = bno;
|
|
cur->bc_rec.a.ar_blockcount = len;
|
|
return xfs_btree_lookup(cur, XFS_LOOKUP_EQ, stat);
|
|
}
|
|
|
|
/*
|
|
* Lookup the first record greater than or equal to [bno, len]
|
|
* in the btree given by cur.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_lookup_ge(
|
|
struct xfs_btree_cur *cur, /* btree cursor */
|
|
xfs_agblock_t bno, /* starting block of extent */
|
|
xfs_extlen_t len, /* length of extent */
|
|
int *stat) /* success/failure */
|
|
{
|
|
cur->bc_rec.a.ar_startblock = bno;
|
|
cur->bc_rec.a.ar_blockcount = len;
|
|
return xfs_btree_lookup(cur, XFS_LOOKUP_GE, stat);
|
|
}
|
|
|
|
/*
|
|
* Lookup the first record less than or equal to [bno, len]
|
|
* in the btree given by cur.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_lookup_le(
|
|
struct xfs_btree_cur *cur, /* btree cursor */
|
|
xfs_agblock_t bno, /* starting block of extent */
|
|
xfs_extlen_t len, /* length of extent */
|
|
int *stat) /* success/failure */
|
|
{
|
|
cur->bc_rec.a.ar_startblock = bno;
|
|
cur->bc_rec.a.ar_blockcount = len;
|
|
return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
|
|
}
|
|
|
|
/*
|
|
* Update the record referred to by cur to the value given
|
|
* by [bno, len].
|
|
* This either works (return 0) or gets an EFSCORRUPTED error.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_update(
|
|
struct xfs_btree_cur *cur, /* btree cursor */
|
|
xfs_agblock_t bno, /* starting block of extent */
|
|
xfs_extlen_t len) /* length of extent */
|
|
{
|
|
union xfs_btree_rec rec;
|
|
|
|
rec.alloc.ar_startblock = cpu_to_be32(bno);
|
|
rec.alloc.ar_blockcount = cpu_to_be32(len);
|
|
return xfs_btree_update(cur, &rec);
|
|
}
|
|
|
|
/*
|
|
* Get the data from the pointed-to record.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_get_rec(
|
|
struct xfs_btree_cur *cur, /* btree cursor */
|
|
xfs_agblock_t *bno, /* output: starting block of extent */
|
|
xfs_extlen_t *len, /* output: length of extent */
|
|
int *stat) /* output: success/failure */
|
|
{
|
|
union xfs_btree_rec *rec;
|
|
int error;
|
|
|
|
error = xfs_btree_get_rec(cur, &rec, stat);
|
|
if (!error && *stat == 1) {
|
|
*bno = be32_to_cpu(rec->alloc.ar_startblock);
|
|
*len = be32_to_cpu(rec->alloc.ar_blockcount);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Compute aligned version of the found extent.
|
|
* Takes alignment and min length into account.
|
|
*/
|
|
STATIC void
|
|
xfs_alloc_compute_aligned(
|
|
xfs_alloc_arg_t *args, /* allocation argument structure */
|
|
xfs_agblock_t foundbno, /* starting block in found extent */
|
|
xfs_extlen_t foundlen, /* length in found extent */
|
|
xfs_agblock_t *resbno, /* result block number */
|
|
xfs_extlen_t *reslen) /* result length */
|
|
{
|
|
xfs_agblock_t bno;
|
|
xfs_extlen_t diff;
|
|
xfs_extlen_t len;
|
|
|
|
if (args->alignment > 1 && foundlen >= args->minlen) {
|
|
bno = roundup(foundbno, args->alignment);
|
|
diff = bno - foundbno;
|
|
len = diff >= foundlen ? 0 : foundlen - diff;
|
|
} else {
|
|
bno = foundbno;
|
|
len = foundlen;
|
|
}
|
|
*resbno = bno;
|
|
*reslen = len;
|
|
}
|
|
|
|
/*
|
|
* Compute best start block and diff for "near" allocations.
|
|
* freelen >= wantlen already checked by caller.
|
|
*/
|
|
STATIC xfs_extlen_t /* difference value (absolute) */
|
|
xfs_alloc_compute_diff(
|
|
xfs_agblock_t wantbno, /* target starting block */
|
|
xfs_extlen_t wantlen, /* target length */
|
|
xfs_extlen_t alignment, /* target alignment */
|
|
xfs_agblock_t freebno, /* freespace's starting block */
|
|
xfs_extlen_t freelen, /* freespace's length */
|
|
xfs_agblock_t *newbnop) /* result: best start block from free */
|
|
{
|
|
xfs_agblock_t freeend; /* end of freespace extent */
|
|
xfs_agblock_t newbno1; /* return block number */
|
|
xfs_agblock_t newbno2; /* other new block number */
|
|
xfs_extlen_t newlen1=0; /* length with newbno1 */
|
|
xfs_extlen_t newlen2=0; /* length with newbno2 */
|
|
xfs_agblock_t wantend; /* end of target extent */
|
|
|
|
ASSERT(freelen >= wantlen);
|
|
freeend = freebno + freelen;
|
|
wantend = wantbno + wantlen;
|
|
if (freebno >= wantbno) {
|
|
if ((newbno1 = roundup(freebno, alignment)) >= freeend)
|
|
newbno1 = NULLAGBLOCK;
|
|
} else if (freeend >= wantend && alignment > 1) {
|
|
newbno1 = roundup(wantbno, alignment);
|
|
newbno2 = newbno1 - alignment;
|
|
if (newbno1 >= freeend)
|
|
newbno1 = NULLAGBLOCK;
|
|
else
|
|
newlen1 = XFS_EXTLEN_MIN(wantlen, freeend - newbno1);
|
|
if (newbno2 < freebno)
|
|
newbno2 = NULLAGBLOCK;
|
|
else
|
|
newlen2 = XFS_EXTLEN_MIN(wantlen, freeend - newbno2);
|
|
if (newbno1 != NULLAGBLOCK && newbno2 != NULLAGBLOCK) {
|
|
if (newlen1 < newlen2 ||
|
|
(newlen1 == newlen2 &&
|
|
XFS_ABSDIFF(newbno1, wantbno) >
|
|
XFS_ABSDIFF(newbno2, wantbno)))
|
|
newbno1 = newbno2;
|
|
} else if (newbno2 != NULLAGBLOCK)
|
|
newbno1 = newbno2;
|
|
} else if (freeend >= wantend) {
|
|
newbno1 = wantbno;
|
|
} else if (alignment > 1) {
|
|
newbno1 = roundup(freeend - wantlen, alignment);
|
|
if (newbno1 > freeend - wantlen &&
|
|
newbno1 - alignment >= freebno)
|
|
newbno1 -= alignment;
|
|
else if (newbno1 >= freeend)
|
|
newbno1 = NULLAGBLOCK;
|
|
} else
|
|
newbno1 = freeend - wantlen;
|
|
*newbnop = newbno1;
|
|
return newbno1 == NULLAGBLOCK ? 0 : XFS_ABSDIFF(newbno1, wantbno);
|
|
}
|
|
|
|
/*
|
|
* Fix up the length, based on mod and prod.
|
|
* len should be k * prod + mod for some k.
|
|
* If len is too small it is returned unchanged.
|
|
* If len hits maxlen it is left alone.
|
|
*/
|
|
STATIC void
|
|
xfs_alloc_fix_len(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_extlen_t k;
|
|
xfs_extlen_t rlen;
|
|
|
|
ASSERT(args->mod < args->prod);
|
|
rlen = args->len;
|
|
ASSERT(rlen >= args->minlen);
|
|
ASSERT(rlen <= args->maxlen);
|
|
if (args->prod <= 1 || rlen < args->mod || rlen == args->maxlen ||
|
|
(args->mod == 0 && rlen < args->prod))
|
|
return;
|
|
k = rlen % args->prod;
|
|
if (k == args->mod)
|
|
return;
|
|
if (k > args->mod) {
|
|
if ((int)(rlen = rlen - k - args->mod) < (int)args->minlen)
|
|
return;
|
|
} else {
|
|
if ((int)(rlen = rlen - args->prod - (args->mod - k)) <
|
|
(int)args->minlen)
|
|
return;
|
|
}
|
|
ASSERT(rlen >= args->minlen);
|
|
ASSERT(rlen <= args->maxlen);
|
|
args->len = rlen;
|
|
}
|
|
|
|
/*
|
|
* Fix up length if there is too little space left in the a.g.
|
|
* Return 1 if ok, 0 if too little, should give up.
|
|
*/
|
|
STATIC int
|
|
xfs_alloc_fix_minleft(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_agf_t *agf; /* a.g. freelist header */
|
|
int diff; /* free space difference */
|
|
|
|
if (args->minleft == 0)
|
|
return 1;
|
|
agf = XFS_BUF_TO_AGF(args->agbp);
|
|
diff = be32_to_cpu(agf->agf_freeblks)
|
|
+ be32_to_cpu(agf->agf_flcount)
|
|
- args->len - args->minleft;
|
|
if (diff >= 0)
|
|
return 1;
|
|
args->len += diff; /* shrink the allocated space */
|
|
if (args->len >= args->minlen)
|
|
return 1;
|
|
args->agbno = NULLAGBLOCK;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Update the two btrees, logically removing from freespace the extent
|
|
* starting at rbno, rlen blocks. The extent is contained within the
|
|
* actual (current) free extent fbno for flen blocks.
|
|
* Flags are passed in indicating whether the cursors are set to the
|
|
* relevant records.
|
|
*/
|
|
STATIC int /* error code */
|
|
xfs_alloc_fixup_trees(
|
|
xfs_btree_cur_t *cnt_cur, /* cursor for by-size btree */
|
|
xfs_btree_cur_t *bno_cur, /* cursor for by-block btree */
|
|
xfs_agblock_t fbno, /* starting block of free extent */
|
|
xfs_extlen_t flen, /* length of free extent */
|
|
xfs_agblock_t rbno, /* starting block of returned extent */
|
|
xfs_extlen_t rlen, /* length of returned extent */
|
|
int flags) /* flags, XFSA_FIXUP_... */
|
|
{
|
|
int error; /* error code */
|
|
int i; /* operation results */
|
|
xfs_agblock_t nfbno1; /* first new free startblock */
|
|
xfs_agblock_t nfbno2; /* second new free startblock */
|
|
xfs_extlen_t nflen1=0; /* first new free length */
|
|
xfs_extlen_t nflen2=0; /* second new free length */
|
|
|
|
/*
|
|
* Look up the record in the by-size tree if necessary.
|
|
*/
|
|
if (flags & XFSA_FIXUP_CNT_OK) {
|
|
#ifdef DEBUG
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, &nfbno1, &nflen1, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(
|
|
i == 1 && nfbno1 == fbno && nflen1 == flen);
|
|
#endif
|
|
} else {
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, fbno, flen, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
}
|
|
/*
|
|
* Look up the record in the by-block tree if necessary.
|
|
*/
|
|
if (flags & XFSA_FIXUP_BNO_OK) {
|
|
#ifdef DEBUG
|
|
if ((error = xfs_alloc_get_rec(bno_cur, &nfbno1, &nflen1, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(
|
|
i == 1 && nfbno1 == fbno && nflen1 == flen);
|
|
#endif
|
|
} else {
|
|
if ((error = xfs_alloc_lookup_eq(bno_cur, fbno, flen, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
}
|
|
|
|
#ifdef DEBUG
|
|
if (bno_cur->bc_nlevels == 1 && cnt_cur->bc_nlevels == 1) {
|
|
struct xfs_btree_block *bnoblock;
|
|
struct xfs_btree_block *cntblock;
|
|
|
|
bnoblock = XFS_BUF_TO_BLOCK(bno_cur->bc_bufs[0]);
|
|
cntblock = XFS_BUF_TO_BLOCK(cnt_cur->bc_bufs[0]);
|
|
|
|
XFS_WANT_CORRUPTED_RETURN(
|
|
bnoblock->bb_numrecs == cntblock->bb_numrecs);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Deal with all four cases: the allocated record is contained
|
|
* within the freespace record, so we can have new freespace
|
|
* at either (or both) end, or no freespace remaining.
|
|
*/
|
|
if (rbno == fbno && rlen == flen)
|
|
nfbno1 = nfbno2 = NULLAGBLOCK;
|
|
else if (rbno == fbno) {
|
|
nfbno1 = rbno + rlen;
|
|
nflen1 = flen - rlen;
|
|
nfbno2 = NULLAGBLOCK;
|
|
} else if (rbno + rlen == fbno + flen) {
|
|
nfbno1 = fbno;
|
|
nflen1 = flen - rlen;
|
|
nfbno2 = NULLAGBLOCK;
|
|
} else {
|
|
nfbno1 = fbno;
|
|
nflen1 = rbno - fbno;
|
|
nfbno2 = rbno + rlen;
|
|
nflen2 = (fbno + flen) - nfbno2;
|
|
}
|
|
/*
|
|
* Delete the entry from the by-size btree.
|
|
*/
|
|
if ((error = xfs_btree_delete(cnt_cur, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
/*
|
|
* Add new by-size btree entry(s).
|
|
*/
|
|
if (nfbno1 != NULLAGBLOCK) {
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno1, nflen1, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 0);
|
|
if ((error = xfs_btree_insert(cnt_cur, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
}
|
|
if (nfbno2 != NULLAGBLOCK) {
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, nfbno2, nflen2, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 0);
|
|
if ((error = xfs_btree_insert(cnt_cur, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
}
|
|
/*
|
|
* Fix up the by-block btree entry(s).
|
|
*/
|
|
if (nfbno1 == NULLAGBLOCK) {
|
|
/*
|
|
* No remaining freespace, just delete the by-block tree entry.
|
|
*/
|
|
if ((error = xfs_btree_delete(bno_cur, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
} else {
|
|
/*
|
|
* Update the by-block entry to start later|be shorter.
|
|
*/
|
|
if ((error = xfs_alloc_update(bno_cur, nfbno1, nflen1)))
|
|
return error;
|
|
}
|
|
if (nfbno2 != NULLAGBLOCK) {
|
|
/*
|
|
* 2 resulting free entries, need to add one.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(bno_cur, nfbno2, nflen2, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 0);
|
|
if ((error = xfs_btree_insert(bno_cur, &i)))
|
|
return error;
|
|
XFS_WANT_CORRUPTED_RETURN(i == 1);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read in the allocation group free block array.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_read_agfl(
|
|
xfs_mount_t *mp, /* mount point structure */
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_agnumber_t agno, /* allocation group number */
|
|
xfs_buf_t **bpp) /* buffer for the ag free block array */
|
|
{
|
|
xfs_buf_t *bp; /* return value */
|
|
int error;
|
|
|
|
ASSERT(agno != NULLAGNUMBER);
|
|
error = xfs_trans_read_buf(
|
|
mp, tp, mp->m_ddev_targp,
|
|
XFS_AG_DADDR(mp, agno, XFS_AGFL_DADDR(mp)),
|
|
XFS_FSS_TO_BB(mp, 1), 0, &bp);
|
|
if (error)
|
|
return error;
|
|
ASSERT(bp);
|
|
ASSERT(!XFS_BUF_GETERROR(bp));
|
|
XFS_BUF_SET_VTYPE_REF(bp, B_FS_AGFL, XFS_AGFL_REF);
|
|
*bpp = bp;
|
|
return 0;
|
|
}
|
|
|
|
STATIC int
|
|
xfs_alloc_update_counters(
|
|
struct xfs_trans *tp,
|
|
struct xfs_perag *pag,
|
|
struct xfs_buf *agbp,
|
|
long len)
|
|
{
|
|
struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
|
|
|
|
pag->pagf_freeblks += len;
|
|
be32_add_cpu(&agf->agf_freeblks, len);
|
|
|
|
xfs_trans_agblocks_delta(tp, len);
|
|
if (unlikely(be32_to_cpu(agf->agf_freeblks) >
|
|
be32_to_cpu(agf->agf_length)))
|
|
return EFSCORRUPTED;
|
|
|
|
xfs_alloc_log_agf(tp, agbp, XFS_AGF_FREEBLKS);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allocation group level functions.
|
|
*/
|
|
|
|
/*
|
|
* Allocate a variable extent in the allocation group agno.
|
|
* Type and bno are used to determine where in the allocation group the
|
|
* extent will start.
|
|
* Extent's length (returned in *len) will be between minlen and maxlen,
|
|
* and of the form k * prod + mod unless there's nothing that large.
|
|
* Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_ag_vextent(
|
|
xfs_alloc_arg_t *args) /* argument structure for allocation */
|
|
{
|
|
int error=0;
|
|
|
|
ASSERT(args->minlen > 0);
|
|
ASSERT(args->maxlen > 0);
|
|
ASSERT(args->minlen <= args->maxlen);
|
|
ASSERT(args->mod < args->prod);
|
|
ASSERT(args->alignment > 0);
|
|
/*
|
|
* Branch to correct routine based on the type.
|
|
*/
|
|
args->wasfromfl = 0;
|
|
switch (args->type) {
|
|
case XFS_ALLOCTYPE_THIS_AG:
|
|
error = xfs_alloc_ag_vextent_size(args);
|
|
break;
|
|
case XFS_ALLOCTYPE_NEAR_BNO:
|
|
error = xfs_alloc_ag_vextent_near(args);
|
|
break;
|
|
case XFS_ALLOCTYPE_THIS_BNO:
|
|
error = xfs_alloc_ag_vextent_exact(args);
|
|
break;
|
|
default:
|
|
ASSERT(0);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
if (error || args->agbno == NULLAGBLOCK)
|
|
return error;
|
|
|
|
ASSERT(args->len >= args->minlen);
|
|
ASSERT(args->len <= args->maxlen);
|
|
ASSERT(!args->wasfromfl || !args->isfl);
|
|
ASSERT(args->agbno % args->alignment == 0);
|
|
|
|
if (!args->wasfromfl) {
|
|
error = xfs_alloc_update_counters(args->tp, args->pag,
|
|
args->agbp,
|
|
-((long)(args->len)));
|
|
if (error)
|
|
return error;
|
|
|
|
/*
|
|
* Search the busylist for these blocks and mark the
|
|
* transaction as synchronous if blocks are found. This
|
|
* avoids the need to block due to a synchronous log
|
|
* force to ensure correct ordering as the synchronous
|
|
* transaction will guarantee that for us.
|
|
*/
|
|
if (xfs_alloc_busy_search(args->mp, args->agno,
|
|
args->agbno, args->len))
|
|
xfs_trans_set_sync(args->tp);
|
|
}
|
|
|
|
if (!args->isfl) {
|
|
xfs_trans_mod_sb(args->tp, args->wasdel ?
|
|
XFS_TRANS_SB_RES_FDBLOCKS :
|
|
XFS_TRANS_SB_FDBLOCKS,
|
|
-((long)(args->len)));
|
|
}
|
|
|
|
XFS_STATS_INC(xs_allocx);
|
|
XFS_STATS_ADD(xs_allocb, args->len);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Allocate a variable extent at exactly agno/bno.
|
|
* Extent's length (returned in *len) will be between minlen and maxlen,
|
|
* and of the form k * prod + mod unless there's nothing that large.
|
|
* Return the starting a.g. block (bno), or NULLAGBLOCK if we can't do it.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_ag_vextent_exact(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_btree_cur_t *bno_cur;/* by block-number btree cursor */
|
|
xfs_btree_cur_t *cnt_cur;/* by count btree cursor */
|
|
xfs_agblock_t end; /* end of allocated extent */
|
|
int error;
|
|
xfs_agblock_t fbno; /* start block of found extent */
|
|
xfs_agblock_t fend; /* end block of found extent */
|
|
xfs_extlen_t flen; /* length of found extent */
|
|
int i; /* success/failure of operation */
|
|
xfs_agblock_t maxend; /* end of maximal extent */
|
|
xfs_agblock_t minend; /* end of minimal extent */
|
|
xfs_extlen_t rlen; /* length of returned extent */
|
|
|
|
ASSERT(args->alignment == 1);
|
|
|
|
/*
|
|
* Allocate/initialize a cursor for the by-number freespace btree.
|
|
*/
|
|
bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_BNO);
|
|
|
|
/*
|
|
* Lookup bno and minlen in the btree (minlen is irrelevant, really).
|
|
* Look for the closest free block <= bno, it must contain bno
|
|
* if any free block does.
|
|
*/
|
|
error = xfs_alloc_lookup_le(bno_cur, args->agbno, args->minlen, &i);
|
|
if (error)
|
|
goto error0;
|
|
if (!i)
|
|
goto not_found;
|
|
|
|
/*
|
|
* Grab the freespace record.
|
|
*/
|
|
error = xfs_alloc_get_rec(bno_cur, &fbno, &flen, &i);
|
|
if (error)
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
ASSERT(fbno <= args->agbno);
|
|
minend = args->agbno + args->minlen;
|
|
maxend = args->agbno + args->maxlen;
|
|
fend = fbno + flen;
|
|
|
|
/*
|
|
* Give up if the freespace isn't long enough for the minimum request.
|
|
*/
|
|
if (fend < minend)
|
|
goto not_found;
|
|
|
|
/*
|
|
* End of extent will be smaller of the freespace end and the
|
|
* maximal requested end.
|
|
*
|
|
* Fix the length according to mod and prod if given.
|
|
*/
|
|
end = XFS_AGBLOCK_MIN(fend, maxend);
|
|
args->len = end - args->agbno;
|
|
xfs_alloc_fix_len(args);
|
|
if (!xfs_alloc_fix_minleft(args))
|
|
goto not_found;
|
|
|
|
rlen = args->len;
|
|
ASSERT(args->agbno + rlen <= fend);
|
|
end = args->agbno + rlen;
|
|
|
|
/*
|
|
* We are allocating agbno for rlen [agbno .. end]
|
|
* Allocate/initialize a cursor for the by-size btree.
|
|
*/
|
|
cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_CNT);
|
|
ASSERT(args->agbno + args->len <=
|
|
be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
|
|
error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen, args->agbno,
|
|
args->len, XFSA_FIXUP_BNO_OK);
|
|
if (error) {
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
|
|
goto error0;
|
|
}
|
|
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
|
|
args->wasfromfl = 0;
|
|
trace_xfs_alloc_exact_done(args);
|
|
return 0;
|
|
|
|
not_found:
|
|
/* Didn't find it, return null. */
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
|
|
args->agbno = NULLAGBLOCK;
|
|
trace_xfs_alloc_exact_notfound(args);
|
|
return 0;
|
|
|
|
error0:
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
|
|
trace_xfs_alloc_exact_error(args);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Search the btree in a given direction via the search cursor and compare
|
|
* the records found against the good extent we've already found.
|
|
*/
|
|
STATIC int
|
|
xfs_alloc_find_best_extent(
|
|
struct xfs_alloc_arg *args, /* allocation argument structure */
|
|
struct xfs_btree_cur **gcur, /* good cursor */
|
|
struct xfs_btree_cur **scur, /* searching cursor */
|
|
xfs_agblock_t gdiff, /* difference for search comparison */
|
|
xfs_agblock_t *sbno, /* extent found by search */
|
|
xfs_extlen_t *slen,
|
|
xfs_extlen_t *slena, /* aligned length */
|
|
int dir) /* 0 = search right, 1 = search left */
|
|
{
|
|
xfs_agblock_t bno;
|
|
xfs_agblock_t new;
|
|
xfs_agblock_t sdiff;
|
|
int error;
|
|
int i;
|
|
|
|
/* The good extent is perfect, no need to search. */
|
|
if (!gdiff)
|
|
goto out_use_good;
|
|
|
|
/*
|
|
* Look until we find a better one, run out of space or run off the end.
|
|
*/
|
|
do {
|
|
error = xfs_alloc_get_rec(*scur, sbno, slen, &i);
|
|
if (error)
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
xfs_alloc_compute_aligned(args, *sbno, *slen, &bno, slena);
|
|
|
|
/*
|
|
* The good extent is closer than this one.
|
|
*/
|
|
if (!dir) {
|
|
if (bno >= args->agbno + gdiff)
|
|
goto out_use_good;
|
|
} else {
|
|
if (bno <= args->agbno - gdiff)
|
|
goto out_use_good;
|
|
}
|
|
|
|
/*
|
|
* Same distance, compare length and pick the best.
|
|
*/
|
|
if (*slena >= args->minlen) {
|
|
args->len = XFS_EXTLEN_MIN(*slena, args->maxlen);
|
|
xfs_alloc_fix_len(args);
|
|
|
|
sdiff = xfs_alloc_compute_diff(args->agbno, args->len,
|
|
args->alignment, *sbno,
|
|
*slen, &new);
|
|
|
|
/*
|
|
* Choose closer size and invalidate other cursor.
|
|
*/
|
|
if (sdiff < gdiff)
|
|
goto out_use_search;
|
|
goto out_use_good;
|
|
}
|
|
|
|
if (!dir)
|
|
error = xfs_btree_increment(*scur, 0, &i);
|
|
else
|
|
error = xfs_btree_decrement(*scur, 0, &i);
|
|
if (error)
|
|
goto error0;
|
|
} while (i);
|
|
|
|
out_use_good:
|
|
xfs_btree_del_cursor(*scur, XFS_BTREE_NOERROR);
|
|
*scur = NULL;
|
|
return 0;
|
|
|
|
out_use_search:
|
|
xfs_btree_del_cursor(*gcur, XFS_BTREE_NOERROR);
|
|
*gcur = NULL;
|
|
return 0;
|
|
|
|
error0:
|
|
/* caller invalidates cursors */
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Allocate a variable extent near bno in the allocation group agno.
|
|
* Extent's length (returned in len) will be between minlen and maxlen,
|
|
* and of the form k * prod + mod unless there's nothing that large.
|
|
* Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_ag_vextent_near(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_btree_cur_t *bno_cur_gt; /* cursor for bno btree, right side */
|
|
xfs_btree_cur_t *bno_cur_lt; /* cursor for bno btree, left side */
|
|
xfs_btree_cur_t *cnt_cur; /* cursor for count btree */
|
|
xfs_agblock_t gtbno; /* start bno of right side entry */
|
|
xfs_agblock_t gtbnoa; /* aligned ... */
|
|
xfs_extlen_t gtdiff; /* difference to right side entry */
|
|
xfs_extlen_t gtlen; /* length of right side entry */
|
|
xfs_extlen_t gtlena = 0; /* aligned ... */
|
|
xfs_agblock_t gtnew; /* useful start bno of right side */
|
|
int error; /* error code */
|
|
int i; /* result code, temporary */
|
|
int j; /* result code, temporary */
|
|
xfs_agblock_t ltbno; /* start bno of left side entry */
|
|
xfs_agblock_t ltbnoa; /* aligned ... */
|
|
xfs_extlen_t ltdiff; /* difference to left side entry */
|
|
xfs_extlen_t ltlen; /* length of left side entry */
|
|
xfs_extlen_t ltlena = 0; /* aligned ... */
|
|
xfs_agblock_t ltnew; /* useful start bno of left side */
|
|
xfs_extlen_t rlen; /* length of returned extent */
|
|
#if defined(DEBUG) && defined(__KERNEL__)
|
|
/*
|
|
* Randomly don't execute the first algorithm.
|
|
*/
|
|
int dofirst; /* set to do first algorithm */
|
|
|
|
dofirst = random32() & 1;
|
|
#endif
|
|
/*
|
|
* Get a cursor for the by-size btree.
|
|
*/
|
|
cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_CNT);
|
|
ltlen = 0;
|
|
bno_cur_lt = bno_cur_gt = NULL;
|
|
/*
|
|
* See if there are any free extents as big as maxlen.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_ge(cnt_cur, 0, args->maxlen, &i)))
|
|
goto error0;
|
|
/*
|
|
* If none, then pick up the last entry in the tree unless the
|
|
* tree is empty.
|
|
*/
|
|
if (!i) {
|
|
if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, <bno,
|
|
<len, &i)))
|
|
goto error0;
|
|
if (i == 0 || ltlen == 0) {
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
return 0;
|
|
}
|
|
ASSERT(i == 1);
|
|
}
|
|
args->wasfromfl = 0;
|
|
/*
|
|
* First algorithm.
|
|
* If the requested extent is large wrt the freespaces available
|
|
* in this a.g., then the cursor will be pointing to a btree entry
|
|
* near the right edge of the tree. If it's in the last btree leaf
|
|
* block, then we just examine all the entries in that block
|
|
* that are big enough, and pick the best one.
|
|
* This is written as a while loop so we can break out of it,
|
|
* but we never loop back to the top.
|
|
*/
|
|
while (xfs_btree_islastblock(cnt_cur, 0)) {
|
|
xfs_extlen_t bdiff;
|
|
int besti=0;
|
|
xfs_extlen_t blen=0;
|
|
xfs_agblock_t bnew=0;
|
|
|
|
#if defined(DEBUG) && defined(__KERNEL__)
|
|
if (!dofirst)
|
|
break;
|
|
#endif
|
|
/*
|
|
* Start from the entry that lookup found, sequence through
|
|
* all larger free blocks. If we're actually pointing at a
|
|
* record smaller than maxlen, go to the start of this block,
|
|
* and skip all those smaller than minlen.
|
|
*/
|
|
if (ltlen || args->alignment > 1) {
|
|
cnt_cur->bc_ptrs[0] = 1;
|
|
do {
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, <bno,
|
|
<len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if (ltlen >= args->minlen)
|
|
break;
|
|
if ((error = xfs_btree_increment(cnt_cur, 0, &i)))
|
|
goto error0;
|
|
} while (i);
|
|
ASSERT(ltlen >= args->minlen);
|
|
if (!i)
|
|
break;
|
|
}
|
|
i = cnt_cur->bc_ptrs[0];
|
|
for (j = 1, blen = 0, bdiff = 0;
|
|
!error && j && (blen < args->maxlen || bdiff > 0);
|
|
error = xfs_btree_increment(cnt_cur, 0, &j)) {
|
|
/*
|
|
* For each entry, decide if it's better than
|
|
* the previous best entry.
|
|
*/
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
xfs_alloc_compute_aligned(args, ltbno, ltlen,
|
|
<bnoa, <lena);
|
|
if (ltlena < args->minlen)
|
|
continue;
|
|
args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
|
|
xfs_alloc_fix_len(args);
|
|
ASSERT(args->len >= args->minlen);
|
|
if (args->len < blen)
|
|
continue;
|
|
ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
|
|
args->alignment, ltbno, ltlen, <new);
|
|
if (ltnew != NULLAGBLOCK &&
|
|
(args->len > blen || ltdiff < bdiff)) {
|
|
bdiff = ltdiff;
|
|
bnew = ltnew;
|
|
blen = args->len;
|
|
besti = cnt_cur->bc_ptrs[0];
|
|
}
|
|
}
|
|
/*
|
|
* It didn't work. We COULD be in a case where
|
|
* there's a good record somewhere, so try again.
|
|
*/
|
|
if (blen == 0)
|
|
break;
|
|
/*
|
|
* Point at the best entry, and retrieve it again.
|
|
*/
|
|
cnt_cur->bc_ptrs[0] = besti;
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, <bno, <len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
ASSERT(ltbno + ltlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
|
|
args->len = blen;
|
|
if (!xfs_alloc_fix_minleft(args)) {
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
trace_xfs_alloc_near_nominleft(args);
|
|
return 0;
|
|
}
|
|
blen = args->len;
|
|
/*
|
|
* We are allocating starting at bnew for blen blocks.
|
|
*/
|
|
args->agbno = bnew;
|
|
ASSERT(bnew >= ltbno);
|
|
ASSERT(bnew + blen <= ltbno + ltlen);
|
|
/*
|
|
* Set up a cursor for the by-bno tree.
|
|
*/
|
|
bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp,
|
|
args->agbp, args->agno, XFS_BTNUM_BNO);
|
|
/*
|
|
* Fix up the btree entries.
|
|
*/
|
|
if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno,
|
|
ltlen, bnew, blen, XFSA_FIXUP_CNT_OK)))
|
|
goto error0;
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
|
|
|
|
trace_xfs_alloc_near_first(args);
|
|
return 0;
|
|
}
|
|
/*
|
|
* Second algorithm.
|
|
* Search in the by-bno tree to the left and to the right
|
|
* simultaneously, until in each case we find a space big enough,
|
|
* or run into the edge of the tree. When we run into the edge,
|
|
* we deallocate that cursor.
|
|
* If both searches succeed, we compare the two spaces and pick
|
|
* the better one.
|
|
* With alignment, it's possible for both to fail; the upper
|
|
* level algorithm that picks allocation groups for allocations
|
|
* is not supposed to do this.
|
|
*/
|
|
/*
|
|
* Allocate and initialize the cursor for the leftward search.
|
|
*/
|
|
bno_cur_lt = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_BNO);
|
|
/*
|
|
* Lookup <= bno to find the leftward search's starting point.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_le(bno_cur_lt, args->agbno, args->maxlen, &i)))
|
|
goto error0;
|
|
if (!i) {
|
|
/*
|
|
* Didn't find anything; use this cursor for the rightward
|
|
* search.
|
|
*/
|
|
bno_cur_gt = bno_cur_lt;
|
|
bno_cur_lt = NULL;
|
|
}
|
|
/*
|
|
* Found something. Duplicate the cursor for the rightward search.
|
|
*/
|
|
else if ((error = xfs_btree_dup_cursor(bno_cur_lt, &bno_cur_gt)))
|
|
goto error0;
|
|
/*
|
|
* Increment the cursor, so we will point at the entry just right
|
|
* of the leftward entry if any, or to the leftmost entry.
|
|
*/
|
|
if ((error = xfs_btree_increment(bno_cur_gt, 0, &i)))
|
|
goto error0;
|
|
if (!i) {
|
|
/*
|
|
* It failed, there are no rightward entries.
|
|
*/
|
|
xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_NOERROR);
|
|
bno_cur_gt = NULL;
|
|
}
|
|
/*
|
|
* Loop going left with the leftward cursor, right with the
|
|
* rightward cursor, until either both directions give up or
|
|
* we find an entry at least as big as minlen.
|
|
*/
|
|
do {
|
|
if (bno_cur_lt) {
|
|
if ((error = xfs_alloc_get_rec(bno_cur_lt, <bno, <len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
xfs_alloc_compute_aligned(args, ltbno, ltlen,
|
|
<bnoa, <lena);
|
|
if (ltlena >= args->minlen)
|
|
break;
|
|
if ((error = xfs_btree_decrement(bno_cur_lt, 0, &i)))
|
|
goto error0;
|
|
if (!i) {
|
|
xfs_btree_del_cursor(bno_cur_lt,
|
|
XFS_BTREE_NOERROR);
|
|
bno_cur_lt = NULL;
|
|
}
|
|
}
|
|
if (bno_cur_gt) {
|
|
if ((error = xfs_alloc_get_rec(bno_cur_gt, >bno, >len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
xfs_alloc_compute_aligned(args, gtbno, gtlen,
|
|
>bnoa, >lena);
|
|
if (gtlena >= args->minlen)
|
|
break;
|
|
if ((error = xfs_btree_increment(bno_cur_gt, 0, &i)))
|
|
goto error0;
|
|
if (!i) {
|
|
xfs_btree_del_cursor(bno_cur_gt,
|
|
XFS_BTREE_NOERROR);
|
|
bno_cur_gt = NULL;
|
|
}
|
|
}
|
|
} while (bno_cur_lt || bno_cur_gt);
|
|
|
|
/*
|
|
* Got both cursors still active, need to find better entry.
|
|
*/
|
|
if (bno_cur_lt && bno_cur_gt) {
|
|
if (ltlena >= args->minlen) {
|
|
/*
|
|
* Left side is good, look for a right side entry.
|
|
*/
|
|
args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
|
|
xfs_alloc_fix_len(args);
|
|
ltdiff = xfs_alloc_compute_diff(args->agbno, args->len,
|
|
args->alignment, ltbno, ltlen, <new);
|
|
|
|
error = xfs_alloc_find_best_extent(args,
|
|
&bno_cur_lt, &bno_cur_gt,
|
|
ltdiff, >bno, >len, >lena,
|
|
0 /* search right */);
|
|
} else {
|
|
ASSERT(gtlena >= args->minlen);
|
|
|
|
/*
|
|
* Right side is good, look for a left side entry.
|
|
*/
|
|
args->len = XFS_EXTLEN_MIN(gtlena, args->maxlen);
|
|
xfs_alloc_fix_len(args);
|
|
gtdiff = xfs_alloc_compute_diff(args->agbno, args->len,
|
|
args->alignment, gtbno, gtlen, >new);
|
|
|
|
error = xfs_alloc_find_best_extent(args,
|
|
&bno_cur_gt, &bno_cur_lt,
|
|
gtdiff, <bno, <len, <lena,
|
|
1 /* search left */);
|
|
}
|
|
|
|
if (error)
|
|
goto error0;
|
|
}
|
|
|
|
/*
|
|
* If we couldn't get anything, give up.
|
|
*/
|
|
if (bno_cur_lt == NULL && bno_cur_gt == NULL) {
|
|
trace_xfs_alloc_size_neither(args);
|
|
args->agbno = NULLAGBLOCK;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* At this point we have selected a freespace entry, either to the
|
|
* left or to the right. If it's on the right, copy all the
|
|
* useful variables to the "left" set so we only have one
|
|
* copy of this code.
|
|
*/
|
|
if (bno_cur_gt) {
|
|
bno_cur_lt = bno_cur_gt;
|
|
bno_cur_gt = NULL;
|
|
ltbno = gtbno;
|
|
ltbnoa = gtbnoa;
|
|
ltlen = gtlen;
|
|
ltlena = gtlena;
|
|
j = 1;
|
|
} else
|
|
j = 0;
|
|
|
|
/*
|
|
* Fix up the length and compute the useful address.
|
|
*/
|
|
args->len = XFS_EXTLEN_MIN(ltlena, args->maxlen);
|
|
xfs_alloc_fix_len(args);
|
|
if (!xfs_alloc_fix_minleft(args)) {
|
|
trace_xfs_alloc_near_nominleft(args);
|
|
xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
return 0;
|
|
}
|
|
rlen = args->len;
|
|
(void)xfs_alloc_compute_diff(args->agbno, rlen, args->alignment, ltbno,
|
|
ltlen, <new);
|
|
ASSERT(ltnew >= ltbno);
|
|
ASSERT(ltnew + rlen <= ltbno + ltlen);
|
|
ASSERT(ltnew + rlen <= be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length));
|
|
args->agbno = ltnew;
|
|
if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur_lt, ltbno, ltlen,
|
|
ltnew, rlen, XFSA_FIXUP_BNO_OK)))
|
|
goto error0;
|
|
|
|
if (j)
|
|
trace_xfs_alloc_near_greater(args);
|
|
else
|
|
trace_xfs_alloc_near_lesser(args);
|
|
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_NOERROR);
|
|
return 0;
|
|
|
|
error0:
|
|
trace_xfs_alloc_near_error(args);
|
|
if (cnt_cur != NULL)
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
|
|
if (bno_cur_lt != NULL)
|
|
xfs_btree_del_cursor(bno_cur_lt, XFS_BTREE_ERROR);
|
|
if (bno_cur_gt != NULL)
|
|
xfs_btree_del_cursor(bno_cur_gt, XFS_BTREE_ERROR);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Allocate a variable extent anywhere in the allocation group agno.
|
|
* Extent's length (returned in len) will be between minlen and maxlen,
|
|
* and of the form k * prod + mod unless there's nothing that large.
|
|
* Return the starting a.g. block, or NULLAGBLOCK if we can't do it.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_ag_vextent_size(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_btree_cur_t *bno_cur; /* cursor for bno btree */
|
|
xfs_btree_cur_t *cnt_cur; /* cursor for cnt btree */
|
|
int error; /* error result */
|
|
xfs_agblock_t fbno; /* start of found freespace */
|
|
xfs_extlen_t flen; /* length of found freespace */
|
|
int i; /* temp status variable */
|
|
xfs_agblock_t rbno; /* returned block number */
|
|
xfs_extlen_t rlen; /* length of returned extent */
|
|
|
|
/*
|
|
* Allocate and initialize a cursor for the by-size btree.
|
|
*/
|
|
cnt_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_CNT);
|
|
bno_cur = NULL;
|
|
/*
|
|
* Look for an entry >= maxlen+alignment-1 blocks.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_ge(cnt_cur, 0,
|
|
args->maxlen + args->alignment - 1, &i)))
|
|
goto error0;
|
|
/*
|
|
* If none, then pick up the last entry in the tree unless the
|
|
* tree is empty.
|
|
*/
|
|
if (!i) {
|
|
if ((error = xfs_alloc_ag_vextent_small(args, cnt_cur, &fbno,
|
|
&flen, &i)))
|
|
goto error0;
|
|
if (i == 0 || flen == 0) {
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
trace_xfs_alloc_size_noentry(args);
|
|
return 0;
|
|
}
|
|
ASSERT(i == 1);
|
|
}
|
|
/*
|
|
* There's a freespace as big as maxlen+alignment-1, get it.
|
|
*/
|
|
else {
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
}
|
|
/*
|
|
* In the first case above, we got the last entry in the
|
|
* by-size btree. Now we check to see if the space hits maxlen
|
|
* once aligned; if not, we search left for something better.
|
|
* This can't happen in the second case above.
|
|
*/
|
|
xfs_alloc_compute_aligned(args, fbno, flen, &rbno, &rlen);
|
|
rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
|
|
XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
|
|
(rlen <= flen && rbno + rlen <= fbno + flen), error0);
|
|
if (rlen < args->maxlen) {
|
|
xfs_agblock_t bestfbno;
|
|
xfs_extlen_t bestflen;
|
|
xfs_agblock_t bestrbno;
|
|
xfs_extlen_t bestrlen;
|
|
|
|
bestrlen = rlen;
|
|
bestrbno = rbno;
|
|
bestflen = flen;
|
|
bestfbno = fbno;
|
|
for (;;) {
|
|
if ((error = xfs_btree_decrement(cnt_cur, 0, &i)))
|
|
goto error0;
|
|
if (i == 0)
|
|
break;
|
|
if ((error = xfs_alloc_get_rec(cnt_cur, &fbno, &flen,
|
|
&i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if (flen < bestrlen)
|
|
break;
|
|
xfs_alloc_compute_aligned(args, fbno, flen,
|
|
&rbno, &rlen);
|
|
rlen = XFS_EXTLEN_MIN(args->maxlen, rlen);
|
|
XFS_WANT_CORRUPTED_GOTO(rlen == 0 ||
|
|
(rlen <= flen && rbno + rlen <= fbno + flen),
|
|
error0);
|
|
if (rlen > bestrlen) {
|
|
bestrlen = rlen;
|
|
bestrbno = rbno;
|
|
bestflen = flen;
|
|
bestfbno = fbno;
|
|
if (rlen == args->maxlen)
|
|
break;
|
|
}
|
|
}
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, bestfbno, bestflen,
|
|
&i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
rlen = bestrlen;
|
|
rbno = bestrbno;
|
|
flen = bestflen;
|
|
fbno = bestfbno;
|
|
}
|
|
args->wasfromfl = 0;
|
|
/*
|
|
* Fix up the length.
|
|
*/
|
|
args->len = rlen;
|
|
xfs_alloc_fix_len(args);
|
|
if (rlen < args->minlen || !xfs_alloc_fix_minleft(args)) {
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
trace_xfs_alloc_size_nominleft(args);
|
|
args->agbno = NULLAGBLOCK;
|
|
return 0;
|
|
}
|
|
rlen = args->len;
|
|
XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0);
|
|
/*
|
|
* Allocate and initialize a cursor for the by-block tree.
|
|
*/
|
|
bno_cur = xfs_allocbt_init_cursor(args->mp, args->tp, args->agbp,
|
|
args->agno, XFS_BTNUM_BNO);
|
|
if ((error = xfs_alloc_fixup_trees(cnt_cur, bno_cur, fbno, flen,
|
|
rbno, rlen, XFSA_FIXUP_CNT_OK)))
|
|
goto error0;
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
|
|
cnt_cur = bno_cur = NULL;
|
|
args->len = rlen;
|
|
args->agbno = rbno;
|
|
XFS_WANT_CORRUPTED_GOTO(
|
|
args->agbno + args->len <=
|
|
be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
|
|
error0);
|
|
trace_xfs_alloc_size_done(args);
|
|
return 0;
|
|
|
|
error0:
|
|
trace_xfs_alloc_size_error(args);
|
|
if (cnt_cur)
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
|
|
if (bno_cur)
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Deal with the case where only small freespaces remain.
|
|
* Either return the contents of the last freespace record,
|
|
* or allocate space from the freelist if there is nothing in the tree.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_ag_vextent_small(
|
|
xfs_alloc_arg_t *args, /* allocation argument structure */
|
|
xfs_btree_cur_t *ccur, /* by-size cursor */
|
|
xfs_agblock_t *fbnop, /* result block number */
|
|
xfs_extlen_t *flenp, /* result length */
|
|
int *stat) /* status: 0-freelist, 1-normal/none */
|
|
{
|
|
int error;
|
|
xfs_agblock_t fbno;
|
|
xfs_extlen_t flen;
|
|
int i;
|
|
|
|
if ((error = xfs_btree_decrement(ccur, 0, &i)))
|
|
goto error0;
|
|
if (i) {
|
|
if ((error = xfs_alloc_get_rec(ccur, &fbno, &flen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
}
|
|
/*
|
|
* Nothing in the btree, try the freelist. Make sure
|
|
* to respect minleft even when pulling from the
|
|
* freelist.
|
|
*/
|
|
else if (args->minlen == 1 && args->alignment == 1 && !args->isfl &&
|
|
(be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_flcount)
|
|
> args->minleft)) {
|
|
error = xfs_alloc_get_freelist(args->tp, args->agbp, &fbno, 0);
|
|
if (error)
|
|
goto error0;
|
|
if (fbno != NULLAGBLOCK) {
|
|
if (args->userdata) {
|
|
xfs_buf_t *bp;
|
|
|
|
bp = xfs_btree_get_bufs(args->mp, args->tp,
|
|
args->agno, fbno, 0);
|
|
xfs_trans_binval(args->tp, bp);
|
|
}
|
|
args->len = 1;
|
|
args->agbno = fbno;
|
|
XFS_WANT_CORRUPTED_GOTO(
|
|
args->agbno + args->len <=
|
|
be32_to_cpu(XFS_BUF_TO_AGF(args->agbp)->agf_length),
|
|
error0);
|
|
args->wasfromfl = 1;
|
|
trace_xfs_alloc_small_freelist(args);
|
|
*stat = 0;
|
|
return 0;
|
|
}
|
|
/*
|
|
* Nothing in the freelist.
|
|
*/
|
|
else
|
|
flen = 0;
|
|
}
|
|
/*
|
|
* Can't allocate from the freelist for some reason.
|
|
*/
|
|
else {
|
|
fbno = NULLAGBLOCK;
|
|
flen = 0;
|
|
}
|
|
/*
|
|
* Can't do the allocation, give up.
|
|
*/
|
|
if (flen < args->minlen) {
|
|
args->agbno = NULLAGBLOCK;
|
|
trace_xfs_alloc_small_notenough(args);
|
|
flen = 0;
|
|
}
|
|
*fbnop = fbno;
|
|
*flenp = flen;
|
|
*stat = 1;
|
|
trace_xfs_alloc_small_done(args);
|
|
return 0;
|
|
|
|
error0:
|
|
trace_xfs_alloc_small_error(args);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Free the extent starting at agno/bno for length.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_free_ag_extent(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_buf_t *agbp, /* buffer for a.g. freelist header */
|
|
xfs_agnumber_t agno, /* allocation group number */
|
|
xfs_agblock_t bno, /* starting block number */
|
|
xfs_extlen_t len, /* length of extent */
|
|
int isfl) /* set if is freelist blocks - no sb acctg */
|
|
{
|
|
xfs_btree_cur_t *bno_cur; /* cursor for by-block btree */
|
|
xfs_btree_cur_t *cnt_cur; /* cursor for by-size btree */
|
|
int error; /* error return value */
|
|
xfs_agblock_t gtbno; /* start of right neighbor block */
|
|
xfs_extlen_t gtlen; /* length of right neighbor block */
|
|
int haveleft; /* have a left neighbor block */
|
|
int haveright; /* have a right neighbor block */
|
|
int i; /* temp, result code */
|
|
xfs_agblock_t ltbno; /* start of left neighbor block */
|
|
xfs_extlen_t ltlen; /* length of left neighbor block */
|
|
xfs_mount_t *mp; /* mount point struct for filesystem */
|
|
xfs_agblock_t nbno; /* new starting block of freespace */
|
|
xfs_extlen_t nlen; /* new length of freespace */
|
|
xfs_perag_t *pag; /* per allocation group data */
|
|
|
|
mp = tp->t_mountp;
|
|
/*
|
|
* Allocate and initialize a cursor for the by-block btree.
|
|
*/
|
|
bno_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_BNO);
|
|
cnt_cur = NULL;
|
|
/*
|
|
* Look for a neighboring block on the left (lower block numbers)
|
|
* that is contiguous with this space.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_le(bno_cur, bno, len, &haveleft)))
|
|
goto error0;
|
|
if (haveleft) {
|
|
/*
|
|
* There is a block to our left.
|
|
*/
|
|
if ((error = xfs_alloc_get_rec(bno_cur, <bno, <len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* It's not contiguous, though.
|
|
*/
|
|
if (ltbno + ltlen < bno)
|
|
haveleft = 0;
|
|
else {
|
|
/*
|
|
* If this failure happens the request to free this
|
|
* space was invalid, it's (partly) already free.
|
|
* Very bad.
|
|
*/
|
|
XFS_WANT_CORRUPTED_GOTO(ltbno + ltlen <= bno, error0);
|
|
}
|
|
}
|
|
/*
|
|
* Look for a neighboring block on the right (higher block numbers)
|
|
* that is contiguous with this space.
|
|
*/
|
|
if ((error = xfs_btree_increment(bno_cur, 0, &haveright)))
|
|
goto error0;
|
|
if (haveright) {
|
|
/*
|
|
* There is a block to our right.
|
|
*/
|
|
if ((error = xfs_alloc_get_rec(bno_cur, >bno, >len, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* It's not contiguous, though.
|
|
*/
|
|
if (bno + len < gtbno)
|
|
haveright = 0;
|
|
else {
|
|
/*
|
|
* If this failure happens the request to free this
|
|
* space was invalid, it's (partly) already free.
|
|
* Very bad.
|
|
*/
|
|
XFS_WANT_CORRUPTED_GOTO(gtbno >= bno + len, error0);
|
|
}
|
|
}
|
|
/*
|
|
* Now allocate and initialize a cursor for the by-size tree.
|
|
*/
|
|
cnt_cur = xfs_allocbt_init_cursor(mp, tp, agbp, agno, XFS_BTNUM_CNT);
|
|
/*
|
|
* Have both left and right contiguous neighbors.
|
|
* Merge all three into a single free block.
|
|
*/
|
|
if (haveleft && haveright) {
|
|
/*
|
|
* Delete the old by-size entry on the left.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if ((error = xfs_btree_delete(cnt_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* Delete the old by-size entry on the right.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if ((error = xfs_btree_delete(cnt_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* Delete the old by-block entry for the right block.
|
|
*/
|
|
if ((error = xfs_btree_delete(bno_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* Move the by-block cursor back to the left neighbor.
|
|
*/
|
|
if ((error = xfs_btree_decrement(bno_cur, 0, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
#ifdef DEBUG
|
|
/*
|
|
* Check that this is the right record: delete didn't
|
|
* mangle the cursor.
|
|
*/
|
|
{
|
|
xfs_agblock_t xxbno;
|
|
xfs_extlen_t xxlen;
|
|
|
|
if ((error = xfs_alloc_get_rec(bno_cur, &xxbno, &xxlen,
|
|
&i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(
|
|
i == 1 && xxbno == ltbno && xxlen == ltlen,
|
|
error0);
|
|
}
|
|
#endif
|
|
/*
|
|
* Update remaining by-block entry to the new, joined block.
|
|
*/
|
|
nbno = ltbno;
|
|
nlen = len + ltlen + gtlen;
|
|
if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
|
|
goto error0;
|
|
}
|
|
/*
|
|
* Have only a left contiguous neighbor.
|
|
* Merge it together with the new freespace.
|
|
*/
|
|
else if (haveleft) {
|
|
/*
|
|
* Delete the old by-size entry on the left.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, ltbno, ltlen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if ((error = xfs_btree_delete(cnt_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* Back up the by-block cursor to the left neighbor, and
|
|
* update its length.
|
|
*/
|
|
if ((error = xfs_btree_decrement(bno_cur, 0, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
nbno = ltbno;
|
|
nlen = len + ltlen;
|
|
if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
|
|
goto error0;
|
|
}
|
|
/*
|
|
* Have only a right contiguous neighbor.
|
|
* Merge it together with the new freespace.
|
|
*/
|
|
else if (haveright) {
|
|
/*
|
|
* Delete the old by-size entry on the right.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, gtbno, gtlen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
if ((error = xfs_btree_delete(cnt_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
/*
|
|
* Update the starting block and length of the right
|
|
* neighbor in the by-block tree.
|
|
*/
|
|
nbno = bno;
|
|
nlen = len + gtlen;
|
|
if ((error = xfs_alloc_update(bno_cur, nbno, nlen)))
|
|
goto error0;
|
|
}
|
|
/*
|
|
* No contiguous neighbors.
|
|
* Insert the new freespace into the by-block tree.
|
|
*/
|
|
else {
|
|
nbno = bno;
|
|
nlen = len;
|
|
if ((error = xfs_btree_insert(bno_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
}
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_NOERROR);
|
|
bno_cur = NULL;
|
|
/*
|
|
* In all cases we need to insert the new freespace in the by-size tree.
|
|
*/
|
|
if ((error = xfs_alloc_lookup_eq(cnt_cur, nbno, nlen, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 0, error0);
|
|
if ((error = xfs_btree_insert(cnt_cur, &i)))
|
|
goto error0;
|
|
XFS_WANT_CORRUPTED_GOTO(i == 1, error0);
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_NOERROR);
|
|
cnt_cur = NULL;
|
|
|
|
/*
|
|
* Update the freespace totals in the ag and superblock.
|
|
*/
|
|
pag = xfs_perag_get(mp, agno);
|
|
error = xfs_alloc_update_counters(tp, pag, agbp, len);
|
|
xfs_perag_put(pag);
|
|
if (error)
|
|
goto error0;
|
|
|
|
if (!isfl)
|
|
xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, (long)len);
|
|
XFS_STATS_INC(xs_freex);
|
|
XFS_STATS_ADD(xs_freeb, len);
|
|
|
|
trace_xfs_free_extent(mp, agno, bno, len, isfl, haveleft, haveright);
|
|
|
|
/*
|
|
* Since blocks move to the free list without the coordination
|
|
* used in xfs_bmap_finish, we can't allow block to be available
|
|
* for reallocation and non-transaction writing (user data)
|
|
* until we know that the transaction that moved it to the free
|
|
* list is permanently on disk. We track the blocks by declaring
|
|
* these blocks as "busy"; the busy list is maintained on a per-ag
|
|
* basis and each transaction records which entries should be removed
|
|
* when the iclog commits to disk. If a busy block is allocated,
|
|
* the iclog is pushed up to the LSN that freed the block.
|
|
*/
|
|
xfs_alloc_busy_insert(tp, agno, bno, len);
|
|
return 0;
|
|
|
|
error0:
|
|
trace_xfs_free_extent(mp, agno, bno, len, isfl, -1, -1);
|
|
if (bno_cur)
|
|
xfs_btree_del_cursor(bno_cur, XFS_BTREE_ERROR);
|
|
if (cnt_cur)
|
|
xfs_btree_del_cursor(cnt_cur, XFS_BTREE_ERROR);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Visible (exported) allocation/free functions.
|
|
* Some of these are used just by xfs_alloc_btree.c and this file.
|
|
*/
|
|
|
|
/*
|
|
* Compute and fill in value of m_ag_maxlevels.
|
|
*/
|
|
void
|
|
xfs_alloc_compute_maxlevels(
|
|
xfs_mount_t *mp) /* file system mount structure */
|
|
{
|
|
int level;
|
|
uint maxblocks;
|
|
uint maxleafents;
|
|
int minleafrecs;
|
|
int minnoderecs;
|
|
|
|
maxleafents = (mp->m_sb.sb_agblocks + 1) / 2;
|
|
minleafrecs = mp->m_alloc_mnr[0];
|
|
minnoderecs = mp->m_alloc_mnr[1];
|
|
maxblocks = (maxleafents + minleafrecs - 1) / minleafrecs;
|
|
for (level = 1; maxblocks > 1; level++)
|
|
maxblocks = (maxblocks + minnoderecs - 1) / minnoderecs;
|
|
mp->m_ag_maxlevels = level;
|
|
}
|
|
|
|
/*
|
|
* Find the length of the longest extent in an AG.
|
|
*/
|
|
xfs_extlen_t
|
|
xfs_alloc_longest_free_extent(
|
|
struct xfs_mount *mp,
|
|
struct xfs_perag *pag)
|
|
{
|
|
xfs_extlen_t need, delta = 0;
|
|
|
|
need = XFS_MIN_FREELIST_PAG(pag, mp);
|
|
if (need > pag->pagf_flcount)
|
|
delta = need - pag->pagf_flcount;
|
|
|
|
if (pag->pagf_longest > delta)
|
|
return pag->pagf_longest - delta;
|
|
return pag->pagf_flcount > 0 || pag->pagf_longest > 0;
|
|
}
|
|
|
|
/*
|
|
* Decide whether to use this allocation group for this allocation.
|
|
* If so, fix up the btree freelist's size.
|
|
*/
|
|
STATIC int /* error */
|
|
xfs_alloc_fix_freelist(
|
|
xfs_alloc_arg_t *args, /* allocation argument structure */
|
|
int flags) /* XFS_ALLOC_FLAG_... */
|
|
{
|
|
xfs_buf_t *agbp; /* agf buffer pointer */
|
|
xfs_agf_t *agf; /* a.g. freespace structure pointer */
|
|
xfs_buf_t *agflbp;/* agfl buffer pointer */
|
|
xfs_agblock_t bno; /* freelist block */
|
|
xfs_extlen_t delta; /* new blocks needed in freelist */
|
|
int error; /* error result code */
|
|
xfs_extlen_t longest;/* longest extent in allocation group */
|
|
xfs_mount_t *mp; /* file system mount point structure */
|
|
xfs_extlen_t need; /* total blocks needed in freelist */
|
|
xfs_perag_t *pag; /* per-ag information structure */
|
|
xfs_alloc_arg_t targs; /* local allocation arguments */
|
|
xfs_trans_t *tp; /* transaction pointer */
|
|
|
|
mp = args->mp;
|
|
|
|
pag = args->pag;
|
|
tp = args->tp;
|
|
if (!pag->pagf_init) {
|
|
if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags,
|
|
&agbp)))
|
|
return error;
|
|
if (!pag->pagf_init) {
|
|
ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK);
|
|
ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
} else
|
|
agbp = NULL;
|
|
|
|
/*
|
|
* If this is a metadata preferred pag and we are user data
|
|
* then try somewhere else if we are not being asked to
|
|
* try harder at this point
|
|
*/
|
|
if (pag->pagf_metadata && args->userdata &&
|
|
(flags & XFS_ALLOC_FLAG_TRYLOCK)) {
|
|
ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
|
|
if (!(flags & XFS_ALLOC_FLAG_FREEING)) {
|
|
/*
|
|
* If it looks like there isn't a long enough extent, or enough
|
|
* total blocks, reject it.
|
|
*/
|
|
need = XFS_MIN_FREELIST_PAG(pag, mp);
|
|
longest = xfs_alloc_longest_free_extent(mp, pag);
|
|
if ((args->minlen + args->alignment + args->minalignslop - 1) >
|
|
longest ||
|
|
((int)(pag->pagf_freeblks + pag->pagf_flcount -
|
|
need - args->total) < (int)args->minleft)) {
|
|
if (agbp)
|
|
xfs_trans_brelse(tp, agbp);
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Get the a.g. freespace buffer.
|
|
* Can fail if we're not blocking on locks, and it's held.
|
|
*/
|
|
if (agbp == NULL) {
|
|
if ((error = xfs_alloc_read_agf(mp, tp, args->agno, flags,
|
|
&agbp)))
|
|
return error;
|
|
if (agbp == NULL) {
|
|
ASSERT(flags & XFS_ALLOC_FLAG_TRYLOCK);
|
|
ASSERT(!(flags & XFS_ALLOC_FLAG_FREEING));
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
}
|
|
/*
|
|
* Figure out how many blocks we should have in the freelist.
|
|
*/
|
|
agf = XFS_BUF_TO_AGF(agbp);
|
|
need = XFS_MIN_FREELIST(agf, mp);
|
|
/*
|
|
* If there isn't enough total or single-extent, reject it.
|
|
*/
|
|
if (!(flags & XFS_ALLOC_FLAG_FREEING)) {
|
|
delta = need > be32_to_cpu(agf->agf_flcount) ?
|
|
(need - be32_to_cpu(agf->agf_flcount)) : 0;
|
|
longest = be32_to_cpu(agf->agf_longest);
|
|
longest = (longest > delta) ? (longest - delta) :
|
|
(be32_to_cpu(agf->agf_flcount) > 0 || longest > 0);
|
|
if ((args->minlen + args->alignment + args->minalignslop - 1) >
|
|
longest ||
|
|
((int)(be32_to_cpu(agf->agf_freeblks) +
|
|
be32_to_cpu(agf->agf_flcount) - need - args->total) <
|
|
(int)args->minleft)) {
|
|
xfs_trans_brelse(tp, agbp);
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
}
|
|
/*
|
|
* Make the freelist shorter if it's too long.
|
|
*/
|
|
while (be32_to_cpu(agf->agf_flcount) > need) {
|
|
xfs_buf_t *bp;
|
|
|
|
error = xfs_alloc_get_freelist(tp, agbp, &bno, 0);
|
|
if (error)
|
|
return error;
|
|
if ((error = xfs_free_ag_extent(tp, agbp, args->agno, bno, 1, 1)))
|
|
return error;
|
|
bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0);
|
|
xfs_trans_binval(tp, bp);
|
|
}
|
|
/*
|
|
* Initialize the args structure.
|
|
*/
|
|
targs.tp = tp;
|
|
targs.mp = mp;
|
|
targs.agbp = agbp;
|
|
targs.agno = args->agno;
|
|
targs.mod = targs.minleft = targs.wasdel = targs.userdata =
|
|
targs.minalignslop = 0;
|
|
targs.alignment = targs.minlen = targs.prod = targs.isfl = 1;
|
|
targs.type = XFS_ALLOCTYPE_THIS_AG;
|
|
targs.pag = pag;
|
|
if ((error = xfs_alloc_read_agfl(mp, tp, targs.agno, &agflbp)))
|
|
return error;
|
|
/*
|
|
* Make the freelist longer if it's too short.
|
|
*/
|
|
while (be32_to_cpu(agf->agf_flcount) < need) {
|
|
targs.agbno = 0;
|
|
targs.maxlen = need - be32_to_cpu(agf->agf_flcount);
|
|
/*
|
|
* Allocate as many blocks as possible at once.
|
|
*/
|
|
if ((error = xfs_alloc_ag_vextent(&targs))) {
|
|
xfs_trans_brelse(tp, agflbp);
|
|
return error;
|
|
}
|
|
/*
|
|
* Stop if we run out. Won't happen if callers are obeying
|
|
* the restrictions correctly. Can happen for free calls
|
|
* on a completely full ag.
|
|
*/
|
|
if (targs.agbno == NULLAGBLOCK) {
|
|
if (flags & XFS_ALLOC_FLAG_FREEING)
|
|
break;
|
|
xfs_trans_brelse(tp, agflbp);
|
|
args->agbp = NULL;
|
|
return 0;
|
|
}
|
|
/*
|
|
* Put each allocated block on the list.
|
|
*/
|
|
for (bno = targs.agbno; bno < targs.agbno + targs.len; bno++) {
|
|
error = xfs_alloc_put_freelist(tp, agbp,
|
|
agflbp, bno, 0);
|
|
if (error)
|
|
return error;
|
|
}
|
|
}
|
|
xfs_trans_brelse(tp, agflbp);
|
|
args->agbp = agbp;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Get a block from the freelist.
|
|
* Returns with the buffer for the block gotten.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_get_freelist(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_buf_t *agbp, /* buffer containing the agf structure */
|
|
xfs_agblock_t *bnop, /* block address retrieved from freelist */
|
|
int btreeblk) /* destination is a AGF btree */
|
|
{
|
|
xfs_agf_t *agf; /* a.g. freespace structure */
|
|
xfs_agfl_t *agfl; /* a.g. freelist structure */
|
|
xfs_buf_t *agflbp;/* buffer for a.g. freelist structure */
|
|
xfs_agblock_t bno; /* block number returned */
|
|
int error;
|
|
int logflags;
|
|
xfs_mount_t *mp; /* mount structure */
|
|
xfs_perag_t *pag; /* per allocation group data */
|
|
|
|
agf = XFS_BUF_TO_AGF(agbp);
|
|
/*
|
|
* Freelist is empty, give up.
|
|
*/
|
|
if (!agf->agf_flcount) {
|
|
*bnop = NULLAGBLOCK;
|
|
return 0;
|
|
}
|
|
/*
|
|
* Read the array of free blocks.
|
|
*/
|
|
mp = tp->t_mountp;
|
|
if ((error = xfs_alloc_read_agfl(mp, tp,
|
|
be32_to_cpu(agf->agf_seqno), &agflbp)))
|
|
return error;
|
|
agfl = XFS_BUF_TO_AGFL(agflbp);
|
|
/*
|
|
* Get the block number and update the data structures.
|
|
*/
|
|
bno = be32_to_cpu(agfl->agfl_bno[be32_to_cpu(agf->agf_flfirst)]);
|
|
be32_add_cpu(&agf->agf_flfirst, 1);
|
|
xfs_trans_brelse(tp, agflbp);
|
|
if (be32_to_cpu(agf->agf_flfirst) == XFS_AGFL_SIZE(mp))
|
|
agf->agf_flfirst = 0;
|
|
|
|
pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
|
|
be32_add_cpu(&agf->agf_flcount, -1);
|
|
xfs_trans_agflist_delta(tp, -1);
|
|
pag->pagf_flcount--;
|
|
xfs_perag_put(pag);
|
|
|
|
logflags = XFS_AGF_FLFIRST | XFS_AGF_FLCOUNT;
|
|
if (btreeblk) {
|
|
be32_add_cpu(&agf->agf_btreeblks, 1);
|
|
pag->pagf_btreeblks++;
|
|
logflags |= XFS_AGF_BTREEBLKS;
|
|
}
|
|
|
|
xfs_alloc_log_agf(tp, agbp, logflags);
|
|
*bnop = bno;
|
|
|
|
/*
|
|
* As blocks are freed, they are added to the per-ag busy list and
|
|
* remain there until the freeing transaction is committed to disk.
|
|
* Now that we have allocated blocks, this list must be searched to see
|
|
* if a block is being reused. If one is, then the freeing transaction
|
|
* must be pushed to disk before this transaction.
|
|
*
|
|
* We do this by setting the current transaction to a sync transaction
|
|
* which guarantees that the freeing transaction is on disk before this
|
|
* transaction. This is done instead of a synchronous log force here so
|
|
* that we don't sit and wait with the AGF locked in the transaction
|
|
* during the log force.
|
|
*/
|
|
if (xfs_alloc_busy_search(mp, be32_to_cpu(agf->agf_seqno), bno, 1))
|
|
xfs_trans_set_sync(tp);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Log the given fields from the agf structure.
|
|
*/
|
|
void
|
|
xfs_alloc_log_agf(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_buf_t *bp, /* buffer for a.g. freelist header */
|
|
int fields) /* mask of fields to be logged (XFS_AGF_...) */
|
|
{
|
|
int first; /* first byte offset */
|
|
int last; /* last byte offset */
|
|
static const short offsets[] = {
|
|
offsetof(xfs_agf_t, agf_magicnum),
|
|
offsetof(xfs_agf_t, agf_versionnum),
|
|
offsetof(xfs_agf_t, agf_seqno),
|
|
offsetof(xfs_agf_t, agf_length),
|
|
offsetof(xfs_agf_t, agf_roots[0]),
|
|
offsetof(xfs_agf_t, agf_levels[0]),
|
|
offsetof(xfs_agf_t, agf_flfirst),
|
|
offsetof(xfs_agf_t, agf_fllast),
|
|
offsetof(xfs_agf_t, agf_flcount),
|
|
offsetof(xfs_agf_t, agf_freeblks),
|
|
offsetof(xfs_agf_t, agf_longest),
|
|
offsetof(xfs_agf_t, agf_btreeblks),
|
|
sizeof(xfs_agf_t)
|
|
};
|
|
|
|
trace_xfs_agf(tp->t_mountp, XFS_BUF_TO_AGF(bp), fields, _RET_IP_);
|
|
|
|
xfs_btree_offsets(fields, offsets, XFS_AGF_NUM_BITS, &first, &last);
|
|
xfs_trans_log_buf(tp, bp, (uint)first, (uint)last);
|
|
}
|
|
|
|
/*
|
|
* Interface for inode allocation to force the pag data to be initialized.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_pagf_init(
|
|
xfs_mount_t *mp, /* file system mount structure */
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_agnumber_t agno, /* allocation group number */
|
|
int flags) /* XFS_ALLOC_FLAGS_... */
|
|
{
|
|
xfs_buf_t *bp;
|
|
int error;
|
|
|
|
if ((error = xfs_alloc_read_agf(mp, tp, agno, flags, &bp)))
|
|
return error;
|
|
if (bp)
|
|
xfs_trans_brelse(tp, bp);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Put the block on the freelist for the allocation group.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_put_freelist(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_buf_t *agbp, /* buffer for a.g. freelist header */
|
|
xfs_buf_t *agflbp,/* buffer for a.g. free block array */
|
|
xfs_agblock_t bno, /* block being freed */
|
|
int btreeblk) /* block came from a AGF btree */
|
|
{
|
|
xfs_agf_t *agf; /* a.g. freespace structure */
|
|
xfs_agfl_t *agfl; /* a.g. free block array */
|
|
__be32 *blockp;/* pointer to array entry */
|
|
int error;
|
|
int logflags;
|
|
xfs_mount_t *mp; /* mount structure */
|
|
xfs_perag_t *pag; /* per allocation group data */
|
|
|
|
agf = XFS_BUF_TO_AGF(agbp);
|
|
mp = tp->t_mountp;
|
|
|
|
if (!agflbp && (error = xfs_alloc_read_agfl(mp, tp,
|
|
be32_to_cpu(agf->agf_seqno), &agflbp)))
|
|
return error;
|
|
agfl = XFS_BUF_TO_AGFL(agflbp);
|
|
be32_add_cpu(&agf->agf_fllast, 1);
|
|
if (be32_to_cpu(agf->agf_fllast) == XFS_AGFL_SIZE(mp))
|
|
agf->agf_fllast = 0;
|
|
|
|
pag = xfs_perag_get(mp, be32_to_cpu(agf->agf_seqno));
|
|
be32_add_cpu(&agf->agf_flcount, 1);
|
|
xfs_trans_agflist_delta(tp, 1);
|
|
pag->pagf_flcount++;
|
|
|
|
logflags = XFS_AGF_FLLAST | XFS_AGF_FLCOUNT;
|
|
if (btreeblk) {
|
|
be32_add_cpu(&agf->agf_btreeblks, -1);
|
|
pag->pagf_btreeblks--;
|
|
logflags |= XFS_AGF_BTREEBLKS;
|
|
}
|
|
xfs_perag_put(pag);
|
|
|
|
xfs_alloc_log_agf(tp, agbp, logflags);
|
|
|
|
ASSERT(be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp));
|
|
blockp = &agfl->agfl_bno[be32_to_cpu(agf->agf_fllast)];
|
|
*blockp = cpu_to_be32(bno);
|
|
xfs_alloc_log_agf(tp, agbp, logflags);
|
|
xfs_trans_log_buf(tp, agflbp,
|
|
(int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl),
|
|
(int)((xfs_caddr_t)blockp - (xfs_caddr_t)agfl +
|
|
sizeof(xfs_agblock_t) - 1));
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read in the allocation group header (free/alloc section).
|
|
*/
|
|
int /* error */
|
|
xfs_read_agf(
|
|
struct xfs_mount *mp, /* mount point structure */
|
|
struct xfs_trans *tp, /* transaction pointer */
|
|
xfs_agnumber_t agno, /* allocation group number */
|
|
int flags, /* XFS_BUF_ */
|
|
struct xfs_buf **bpp) /* buffer for the ag freelist header */
|
|
{
|
|
struct xfs_agf *agf; /* ag freelist header */
|
|
int agf_ok; /* set if agf is consistent */
|
|
int error;
|
|
|
|
ASSERT(agno != NULLAGNUMBER);
|
|
error = xfs_trans_read_buf(
|
|
mp, tp, mp->m_ddev_targp,
|
|
XFS_AG_DADDR(mp, agno, XFS_AGF_DADDR(mp)),
|
|
XFS_FSS_TO_BB(mp, 1), flags, bpp);
|
|
if (error)
|
|
return error;
|
|
if (!*bpp)
|
|
return 0;
|
|
|
|
ASSERT(!XFS_BUF_GETERROR(*bpp));
|
|
agf = XFS_BUF_TO_AGF(*bpp);
|
|
|
|
/*
|
|
* Validate the magic number of the agf block.
|
|
*/
|
|
agf_ok =
|
|
be32_to_cpu(agf->agf_magicnum) == XFS_AGF_MAGIC &&
|
|
XFS_AGF_GOOD_VERSION(be32_to_cpu(agf->agf_versionnum)) &&
|
|
be32_to_cpu(agf->agf_freeblks) <= be32_to_cpu(agf->agf_length) &&
|
|
be32_to_cpu(agf->agf_flfirst) < XFS_AGFL_SIZE(mp) &&
|
|
be32_to_cpu(agf->agf_fllast) < XFS_AGFL_SIZE(mp) &&
|
|
be32_to_cpu(agf->agf_flcount) <= XFS_AGFL_SIZE(mp) &&
|
|
be32_to_cpu(agf->agf_seqno) == agno;
|
|
if (xfs_sb_version_haslazysbcount(&mp->m_sb))
|
|
agf_ok = agf_ok && be32_to_cpu(agf->agf_btreeblks) <=
|
|
be32_to_cpu(agf->agf_length);
|
|
if (unlikely(XFS_TEST_ERROR(!agf_ok, mp, XFS_ERRTAG_ALLOC_READ_AGF,
|
|
XFS_RANDOM_ALLOC_READ_AGF))) {
|
|
XFS_CORRUPTION_ERROR("xfs_alloc_read_agf",
|
|
XFS_ERRLEVEL_LOW, mp, agf);
|
|
xfs_trans_brelse(tp, *bpp);
|
|
return XFS_ERROR(EFSCORRUPTED);
|
|
}
|
|
XFS_BUF_SET_VTYPE_REF(*bpp, B_FS_AGF, XFS_AGF_REF);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Read in the allocation group header (free/alloc section).
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_read_agf(
|
|
struct xfs_mount *mp, /* mount point structure */
|
|
struct xfs_trans *tp, /* transaction pointer */
|
|
xfs_agnumber_t agno, /* allocation group number */
|
|
int flags, /* XFS_ALLOC_FLAG_... */
|
|
struct xfs_buf **bpp) /* buffer for the ag freelist header */
|
|
{
|
|
struct xfs_agf *agf; /* ag freelist header */
|
|
struct xfs_perag *pag; /* per allocation group data */
|
|
int error;
|
|
|
|
ASSERT(agno != NULLAGNUMBER);
|
|
|
|
error = xfs_read_agf(mp, tp, agno,
|
|
(flags & XFS_ALLOC_FLAG_TRYLOCK) ? XBF_TRYLOCK : 0,
|
|
bpp);
|
|
if (error)
|
|
return error;
|
|
if (!*bpp)
|
|
return 0;
|
|
ASSERT(!XFS_BUF_GETERROR(*bpp));
|
|
|
|
agf = XFS_BUF_TO_AGF(*bpp);
|
|
pag = xfs_perag_get(mp, agno);
|
|
if (!pag->pagf_init) {
|
|
pag->pagf_freeblks = be32_to_cpu(agf->agf_freeblks);
|
|
pag->pagf_btreeblks = be32_to_cpu(agf->agf_btreeblks);
|
|
pag->pagf_flcount = be32_to_cpu(agf->agf_flcount);
|
|
pag->pagf_longest = be32_to_cpu(agf->agf_longest);
|
|
pag->pagf_levels[XFS_BTNUM_BNOi] =
|
|
be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]);
|
|
pag->pagf_levels[XFS_BTNUM_CNTi] =
|
|
be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]);
|
|
spin_lock_init(&pag->pagb_lock);
|
|
pag->pagb_count = 0;
|
|
pag->pagb_tree = RB_ROOT;
|
|
pag->pagf_init = 1;
|
|
}
|
|
#ifdef DEBUG
|
|
else if (!XFS_FORCED_SHUTDOWN(mp)) {
|
|
ASSERT(pag->pagf_freeblks == be32_to_cpu(agf->agf_freeblks));
|
|
ASSERT(pag->pagf_btreeblks == be32_to_cpu(agf->agf_btreeblks));
|
|
ASSERT(pag->pagf_flcount == be32_to_cpu(agf->agf_flcount));
|
|
ASSERT(pag->pagf_longest == be32_to_cpu(agf->agf_longest));
|
|
ASSERT(pag->pagf_levels[XFS_BTNUM_BNOi] ==
|
|
be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNOi]));
|
|
ASSERT(pag->pagf_levels[XFS_BTNUM_CNTi] ==
|
|
be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNTi]));
|
|
}
|
|
#endif
|
|
xfs_perag_put(pag);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allocate an extent (variable-size).
|
|
* Depending on the allocation type, we either look in a single allocation
|
|
* group or loop over the allocation groups to find the result.
|
|
*/
|
|
int /* error */
|
|
xfs_alloc_vextent(
|
|
xfs_alloc_arg_t *args) /* allocation argument structure */
|
|
{
|
|
xfs_agblock_t agsize; /* allocation group size */
|
|
int error;
|
|
int flags; /* XFS_ALLOC_FLAG_... locking flags */
|
|
xfs_extlen_t minleft;/* minimum left value, temp copy */
|
|
xfs_mount_t *mp; /* mount structure pointer */
|
|
xfs_agnumber_t sagno; /* starting allocation group number */
|
|
xfs_alloctype_t type; /* input allocation type */
|
|
int bump_rotor = 0;
|
|
int no_min = 0;
|
|
xfs_agnumber_t rotorstep = xfs_rotorstep; /* inode32 agf stepper */
|
|
|
|
mp = args->mp;
|
|
type = args->otype = args->type;
|
|
args->agbno = NULLAGBLOCK;
|
|
/*
|
|
* Just fix this up, for the case where the last a.g. is shorter
|
|
* (or there's only one a.g.) and the caller couldn't easily figure
|
|
* that out (xfs_bmap_alloc).
|
|
*/
|
|
agsize = mp->m_sb.sb_agblocks;
|
|
if (args->maxlen > agsize)
|
|
args->maxlen = agsize;
|
|
if (args->alignment == 0)
|
|
args->alignment = 1;
|
|
ASSERT(XFS_FSB_TO_AGNO(mp, args->fsbno) < mp->m_sb.sb_agcount);
|
|
ASSERT(XFS_FSB_TO_AGBNO(mp, args->fsbno) < agsize);
|
|
ASSERT(args->minlen <= args->maxlen);
|
|
ASSERT(args->minlen <= agsize);
|
|
ASSERT(args->mod < args->prod);
|
|
if (XFS_FSB_TO_AGNO(mp, args->fsbno) >= mp->m_sb.sb_agcount ||
|
|
XFS_FSB_TO_AGBNO(mp, args->fsbno) >= agsize ||
|
|
args->minlen > args->maxlen || args->minlen > agsize ||
|
|
args->mod >= args->prod) {
|
|
args->fsbno = NULLFSBLOCK;
|
|
trace_xfs_alloc_vextent_badargs(args);
|
|
return 0;
|
|
}
|
|
minleft = args->minleft;
|
|
|
|
switch (type) {
|
|
case XFS_ALLOCTYPE_THIS_AG:
|
|
case XFS_ALLOCTYPE_NEAR_BNO:
|
|
case XFS_ALLOCTYPE_THIS_BNO:
|
|
/*
|
|
* These three force us into a single a.g.
|
|
*/
|
|
args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
|
|
args->pag = xfs_perag_get(mp, args->agno);
|
|
args->minleft = 0;
|
|
error = xfs_alloc_fix_freelist(args, 0);
|
|
args->minleft = minleft;
|
|
if (error) {
|
|
trace_xfs_alloc_vextent_nofix(args);
|
|
goto error0;
|
|
}
|
|
if (!args->agbp) {
|
|
trace_xfs_alloc_vextent_noagbp(args);
|
|
break;
|
|
}
|
|
args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
|
|
if ((error = xfs_alloc_ag_vextent(args)))
|
|
goto error0;
|
|
break;
|
|
case XFS_ALLOCTYPE_START_BNO:
|
|
/*
|
|
* Try near allocation first, then anywhere-in-ag after
|
|
* the first a.g. fails.
|
|
*/
|
|
if ((args->userdata == XFS_ALLOC_INITIAL_USER_DATA) &&
|
|
(mp->m_flags & XFS_MOUNT_32BITINODES)) {
|
|
args->fsbno = XFS_AGB_TO_FSB(mp,
|
|
((mp->m_agfrotor / rotorstep) %
|
|
mp->m_sb.sb_agcount), 0);
|
|
bump_rotor = 1;
|
|
}
|
|
args->agbno = XFS_FSB_TO_AGBNO(mp, args->fsbno);
|
|
args->type = XFS_ALLOCTYPE_NEAR_BNO;
|
|
/* FALLTHROUGH */
|
|
case XFS_ALLOCTYPE_ANY_AG:
|
|
case XFS_ALLOCTYPE_START_AG:
|
|
case XFS_ALLOCTYPE_FIRST_AG:
|
|
/*
|
|
* Rotate through the allocation groups looking for a winner.
|
|
*/
|
|
if (type == XFS_ALLOCTYPE_ANY_AG) {
|
|
/*
|
|
* Start with the last place we left off.
|
|
*/
|
|
args->agno = sagno = (mp->m_agfrotor / rotorstep) %
|
|
mp->m_sb.sb_agcount;
|
|
args->type = XFS_ALLOCTYPE_THIS_AG;
|
|
flags = XFS_ALLOC_FLAG_TRYLOCK;
|
|
} else if (type == XFS_ALLOCTYPE_FIRST_AG) {
|
|
/*
|
|
* Start with allocation group given by bno.
|
|
*/
|
|
args->agno = XFS_FSB_TO_AGNO(mp, args->fsbno);
|
|
args->type = XFS_ALLOCTYPE_THIS_AG;
|
|
sagno = 0;
|
|
flags = 0;
|
|
} else {
|
|
if (type == XFS_ALLOCTYPE_START_AG)
|
|
args->type = XFS_ALLOCTYPE_THIS_AG;
|
|
/*
|
|
* Start with the given allocation group.
|
|
*/
|
|
args->agno = sagno = XFS_FSB_TO_AGNO(mp, args->fsbno);
|
|
flags = XFS_ALLOC_FLAG_TRYLOCK;
|
|
}
|
|
/*
|
|
* Loop over allocation groups twice; first time with
|
|
* trylock set, second time without.
|
|
*/
|
|
for (;;) {
|
|
args->pag = xfs_perag_get(mp, args->agno);
|
|
if (no_min) args->minleft = 0;
|
|
error = xfs_alloc_fix_freelist(args, flags);
|
|
args->minleft = minleft;
|
|
if (error) {
|
|
trace_xfs_alloc_vextent_nofix(args);
|
|
goto error0;
|
|
}
|
|
/*
|
|
* If we get a buffer back then the allocation will fly.
|
|
*/
|
|
if (args->agbp) {
|
|
if ((error = xfs_alloc_ag_vextent(args)))
|
|
goto error0;
|
|
break;
|
|
}
|
|
|
|
trace_xfs_alloc_vextent_loopfailed(args);
|
|
|
|
/*
|
|
* Didn't work, figure out the next iteration.
|
|
*/
|
|
if (args->agno == sagno &&
|
|
type == XFS_ALLOCTYPE_START_BNO)
|
|
args->type = XFS_ALLOCTYPE_THIS_AG;
|
|
/*
|
|
* For the first allocation, we can try any AG to get
|
|
* space. However, if we already have allocated a
|
|
* block, we don't want to try AGs whose number is below
|
|
* sagno. Otherwise, we may end up with out-of-order
|
|
* locking of AGF, which might cause deadlock.
|
|
*/
|
|
if (++(args->agno) == mp->m_sb.sb_agcount) {
|
|
if (args->firstblock != NULLFSBLOCK)
|
|
args->agno = sagno;
|
|
else
|
|
args->agno = 0;
|
|
}
|
|
/*
|
|
* Reached the starting a.g., must either be done
|
|
* or switch to non-trylock mode.
|
|
*/
|
|
if (args->agno == sagno) {
|
|
if (no_min == 1) {
|
|
args->agbno = NULLAGBLOCK;
|
|
trace_xfs_alloc_vextent_allfailed(args);
|
|
break;
|
|
}
|
|
if (flags == 0) {
|
|
no_min = 1;
|
|
} else {
|
|
flags = 0;
|
|
if (type == XFS_ALLOCTYPE_START_BNO) {
|
|
args->agbno = XFS_FSB_TO_AGBNO(mp,
|
|
args->fsbno);
|
|
args->type = XFS_ALLOCTYPE_NEAR_BNO;
|
|
}
|
|
}
|
|
}
|
|
xfs_perag_put(args->pag);
|
|
}
|
|
if (bump_rotor || (type == XFS_ALLOCTYPE_ANY_AG)) {
|
|
if (args->agno == sagno)
|
|
mp->m_agfrotor = (mp->m_agfrotor + 1) %
|
|
(mp->m_sb.sb_agcount * rotorstep);
|
|
else
|
|
mp->m_agfrotor = (args->agno * rotorstep + 1) %
|
|
(mp->m_sb.sb_agcount * rotorstep);
|
|
}
|
|
break;
|
|
default:
|
|
ASSERT(0);
|
|
/* NOTREACHED */
|
|
}
|
|
if (args->agbno == NULLAGBLOCK)
|
|
args->fsbno = NULLFSBLOCK;
|
|
else {
|
|
args->fsbno = XFS_AGB_TO_FSB(mp, args->agno, args->agbno);
|
|
#ifdef DEBUG
|
|
ASSERT(args->len >= args->minlen);
|
|
ASSERT(args->len <= args->maxlen);
|
|
ASSERT(args->agbno % args->alignment == 0);
|
|
XFS_AG_CHECK_DADDR(mp, XFS_FSB_TO_DADDR(mp, args->fsbno),
|
|
args->len);
|
|
#endif
|
|
}
|
|
xfs_perag_put(args->pag);
|
|
return 0;
|
|
error0:
|
|
xfs_perag_put(args->pag);
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Free an extent.
|
|
* Just break up the extent address and hand off to xfs_free_ag_extent
|
|
* after fixing up the freelist.
|
|
*/
|
|
int /* error */
|
|
xfs_free_extent(
|
|
xfs_trans_t *tp, /* transaction pointer */
|
|
xfs_fsblock_t bno, /* starting block number of extent */
|
|
xfs_extlen_t len) /* length of extent */
|
|
{
|
|
xfs_alloc_arg_t args;
|
|
int error;
|
|
|
|
ASSERT(len != 0);
|
|
memset(&args, 0, sizeof(xfs_alloc_arg_t));
|
|
args.tp = tp;
|
|
args.mp = tp->t_mountp;
|
|
|
|
/*
|
|
* validate that the block number is legal - the enables us to detect
|
|
* and handle a silent filesystem corruption rather than crashing.
|
|
*/
|
|
args.agno = XFS_FSB_TO_AGNO(args.mp, bno);
|
|
if (args.agno >= args.mp->m_sb.sb_agcount)
|
|
return EFSCORRUPTED;
|
|
|
|
args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno);
|
|
if (args.agbno >= args.mp->m_sb.sb_agblocks)
|
|
return EFSCORRUPTED;
|
|
|
|
args.pag = xfs_perag_get(args.mp, args.agno);
|
|
ASSERT(args.pag);
|
|
|
|
error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
|
|
if (error)
|
|
goto error0;
|
|
|
|
/* validate the extent size is legal now we have the agf locked */
|
|
if (args.agbno + len >
|
|
be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length)) {
|
|
error = EFSCORRUPTED;
|
|
goto error0;
|
|
}
|
|
|
|
error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0);
|
|
error0:
|
|
xfs_perag_put(args.pag);
|
|
return error;
|
|
}
|
|
|
|
|
|
/*
|
|
* AG Busy list management
|
|
* The busy list contains block ranges that have been freed but whose
|
|
* transactions have not yet hit disk. If any block listed in a busy
|
|
* list is reused, the transaction that freed it must be forced to disk
|
|
* before continuing to use the block.
|
|
*
|
|
* xfs_alloc_busy_insert - add to the per-ag busy list
|
|
* xfs_alloc_busy_clear - remove an item from the per-ag busy list
|
|
* xfs_alloc_busy_search - search for a busy extent
|
|
*/
|
|
|
|
/*
|
|
* Insert a new extent into the busy tree.
|
|
*
|
|
* The busy extent tree is indexed by the start block of the busy extent.
|
|
* there can be multiple overlapping ranges in the busy extent tree but only
|
|
* ever one entry at a given start block. The reason for this is that
|
|
* multi-block extents can be freed, then smaller chunks of that extent
|
|
* allocated and freed again before the first transaction commit is on disk.
|
|
* If the exact same start block is freed a second time, we have to wait for
|
|
* that busy extent to pass out of the tree before the new extent is inserted.
|
|
* There are two main cases we have to handle here.
|
|
*
|
|
* The first case is a transaction that triggers a "free - allocate - free"
|
|
* cycle. This can occur during btree manipulations as a btree block is freed
|
|
* to the freelist, then allocated from the free list, then freed again. In
|
|
* this case, the second extxpnet free is what triggers the duplicate and as
|
|
* such the transaction IDs should match. Because the extent was allocated in
|
|
* this transaction, the transaction must be marked as synchronous. This is
|
|
* true for all cases where the free/alloc/free occurs in the one transaction,
|
|
* hence the addition of the ASSERT(tp->t_flags & XFS_TRANS_SYNC) to this case.
|
|
* This serves to catch violations of the second case quite effectively.
|
|
*
|
|
* The second case is where the free/alloc/free occur in different
|
|
* transactions. In this case, the thread freeing the extent the second time
|
|
* can't mark the extent busy immediately because it is already tracked in a
|
|
* transaction that may be committing. When the log commit for the existing
|
|
* busy extent completes, the busy extent will be removed from the tree. If we
|
|
* allow the second busy insert to continue using that busy extent structure,
|
|
* it can be freed before this transaction is safely in the log. Hence our
|
|
* only option in this case is to force the log to remove the existing busy
|
|
* extent from the list before we insert the new one with the current
|
|
* transaction ID.
|
|
*
|
|
* The problem we are trying to avoid in the free-alloc-free in separate
|
|
* transactions is most easily described with a timeline:
|
|
*
|
|
* Thread 1 Thread 2 Thread 3 xfslogd
|
|
* xact alloc
|
|
* free X
|
|
* mark busy
|
|
* commit xact
|
|
* free xact
|
|
* xact alloc
|
|
* alloc X
|
|
* busy search
|
|
* mark xact sync
|
|
* commit xact
|
|
* free xact
|
|
* force log
|
|
* checkpoint starts
|
|
* ....
|
|
* xact alloc
|
|
* free X
|
|
* mark busy
|
|
* finds match
|
|
* *** KABOOM! ***
|
|
* ....
|
|
* log IO completes
|
|
* unbusy X
|
|
* checkpoint completes
|
|
*
|
|
* By issuing a log force in thread 3 @ "KABOOM", the thread will block until
|
|
* the checkpoint completes, and the busy extent it matched will have been
|
|
* removed from the tree when it is woken. Hence it can then continue safely.
|
|
*
|
|
* However, to ensure this matching process is robust, we need to use the
|
|
* transaction ID for identifying transaction, as delayed logging results in
|
|
* the busy extent and transaction lifecycles being different. i.e. the busy
|
|
* extent is active for a lot longer than the transaction. Hence the
|
|
* transaction structure can be freed and reallocated, then mark the same
|
|
* extent busy again in the new transaction. In this case the new transaction
|
|
* will have a different tid but can have the same address, and hence we need
|
|
* to check against the tid.
|
|
*
|
|
* Future: for delayed logging, we could avoid the log force if the extent was
|
|
* first freed in the current checkpoint sequence. This, however, requires the
|
|
* ability to pin the current checkpoint in memory until this transaction
|
|
* commits to ensure that both the original free and the current one combine
|
|
* logically into the one checkpoint. If the checkpoint sequences are
|
|
* different, however, we still need to wait on a log force.
|
|
*/
|
|
void
|
|
xfs_alloc_busy_insert(
|
|
struct xfs_trans *tp,
|
|
xfs_agnumber_t agno,
|
|
xfs_agblock_t bno,
|
|
xfs_extlen_t len)
|
|
{
|
|
struct xfs_busy_extent *new;
|
|
struct xfs_busy_extent *busyp;
|
|
struct xfs_perag *pag;
|
|
struct rb_node **rbp;
|
|
struct rb_node *parent;
|
|
int match;
|
|
|
|
|
|
new = kmem_zalloc(sizeof(struct xfs_busy_extent), KM_MAYFAIL);
|
|
if (!new) {
|
|
/*
|
|
* No Memory! Since it is now not possible to track the free
|
|
* block, make this a synchronous transaction to insure that
|
|
* the block is not reused before this transaction commits.
|
|
*/
|
|
trace_xfs_alloc_busy(tp, agno, bno, len, 1);
|
|
xfs_trans_set_sync(tp);
|
|
return;
|
|
}
|
|
|
|
new->agno = agno;
|
|
new->bno = bno;
|
|
new->length = len;
|
|
new->tid = xfs_log_get_trans_ident(tp);
|
|
|
|
INIT_LIST_HEAD(&new->list);
|
|
|
|
/* trace before insert to be able to see failed inserts */
|
|
trace_xfs_alloc_busy(tp, agno, bno, len, 0);
|
|
|
|
pag = xfs_perag_get(tp->t_mountp, new->agno);
|
|
restart:
|
|
spin_lock(&pag->pagb_lock);
|
|
rbp = &pag->pagb_tree.rb_node;
|
|
parent = NULL;
|
|
busyp = NULL;
|
|
match = 0;
|
|
while (*rbp && match >= 0) {
|
|
parent = *rbp;
|
|
busyp = rb_entry(parent, struct xfs_busy_extent, rb_node);
|
|
|
|
if (new->bno < busyp->bno) {
|
|
/* may overlap, but exact start block is lower */
|
|
rbp = &(*rbp)->rb_left;
|
|
if (new->bno + new->length > busyp->bno)
|
|
match = busyp->tid == new->tid ? 1 : -1;
|
|
} else if (new->bno > busyp->bno) {
|
|
/* may overlap, but exact start block is higher */
|
|
rbp = &(*rbp)->rb_right;
|
|
if (bno < busyp->bno + busyp->length)
|
|
match = busyp->tid == new->tid ? 1 : -1;
|
|
} else {
|
|
match = busyp->tid == new->tid ? 1 : -1;
|
|
break;
|
|
}
|
|
}
|
|
if (match < 0) {
|
|
/* overlap marked busy in different transaction */
|
|
spin_unlock(&pag->pagb_lock);
|
|
xfs_log_force(tp->t_mountp, XFS_LOG_SYNC);
|
|
goto restart;
|
|
}
|
|
if (match > 0) {
|
|
/*
|
|
* overlap marked busy in same transaction. Update if exact
|
|
* start block match, otherwise combine the busy extents into
|
|
* a single range.
|
|
*/
|
|
if (busyp->bno == new->bno) {
|
|
busyp->length = max(busyp->length, new->length);
|
|
spin_unlock(&pag->pagb_lock);
|
|
ASSERT(tp->t_flags & XFS_TRANS_SYNC);
|
|
xfs_perag_put(pag);
|
|
kmem_free(new);
|
|
return;
|
|
}
|
|
rb_erase(&busyp->rb_node, &pag->pagb_tree);
|
|
new->length = max(busyp->bno + busyp->length,
|
|
new->bno + new->length) -
|
|
min(busyp->bno, new->bno);
|
|
new->bno = min(busyp->bno, new->bno);
|
|
} else
|
|
busyp = NULL;
|
|
|
|
rb_link_node(&new->rb_node, parent, rbp);
|
|
rb_insert_color(&new->rb_node, &pag->pagb_tree);
|
|
|
|
list_add(&new->list, &tp->t_busy);
|
|
spin_unlock(&pag->pagb_lock);
|
|
xfs_perag_put(pag);
|
|
kmem_free(busyp);
|
|
}
|
|
|
|
/*
|
|
* Search for a busy extent within the range of the extent we are about to
|
|
* allocate. You need to be holding the busy extent tree lock when calling
|
|
* xfs_alloc_busy_search(). This function returns 0 for no overlapping busy
|
|
* extent, -1 for an overlapping but not exact busy extent, and 1 for an exact
|
|
* match. This is done so that a non-zero return indicates an overlap that
|
|
* will require a synchronous transaction, but it can still be
|
|
* used to distinguish between a partial or exact match.
|
|
*/
|
|
int
|
|
xfs_alloc_busy_search(
|
|
struct xfs_mount *mp,
|
|
xfs_agnumber_t agno,
|
|
xfs_agblock_t bno,
|
|
xfs_extlen_t len)
|
|
{
|
|
struct xfs_perag *pag;
|
|
struct rb_node *rbp;
|
|
struct xfs_busy_extent *busyp;
|
|
int match = 0;
|
|
|
|
pag = xfs_perag_get(mp, agno);
|
|
spin_lock(&pag->pagb_lock);
|
|
|
|
rbp = pag->pagb_tree.rb_node;
|
|
|
|
/* find closest start bno overlap */
|
|
while (rbp) {
|
|
busyp = rb_entry(rbp, struct xfs_busy_extent, rb_node);
|
|
if (bno < busyp->bno) {
|
|
/* may overlap, but exact start block is lower */
|
|
if (bno + len > busyp->bno)
|
|
match = -1;
|
|
rbp = rbp->rb_left;
|
|
} else if (bno > busyp->bno) {
|
|
/* may overlap, but exact start block is higher */
|
|
if (bno < busyp->bno + busyp->length)
|
|
match = -1;
|
|
rbp = rbp->rb_right;
|
|
} else {
|
|
/* bno matches busyp, length determines exact match */
|
|
match = (busyp->length == len) ? 1 : -1;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock(&pag->pagb_lock);
|
|
trace_xfs_alloc_busysearch(mp, agno, bno, len, !!match);
|
|
xfs_perag_put(pag);
|
|
return match;
|
|
}
|
|
|
|
void
|
|
xfs_alloc_busy_clear(
|
|
struct xfs_mount *mp,
|
|
struct xfs_busy_extent *busyp)
|
|
{
|
|
struct xfs_perag *pag;
|
|
|
|
trace_xfs_alloc_unbusy(mp, busyp->agno, busyp->bno,
|
|
busyp->length);
|
|
|
|
ASSERT(xfs_alloc_busy_search(mp, busyp->agno, busyp->bno,
|
|
busyp->length) == 1);
|
|
|
|
list_del_init(&busyp->list);
|
|
|
|
pag = xfs_perag_get(mp, busyp->agno);
|
|
spin_lock(&pag->pagb_lock);
|
|
rb_erase(&busyp->rb_node, &pag->pagb_tree);
|
|
spin_unlock(&pag->pagb_lock);
|
|
xfs_perag_put(pag);
|
|
|
|
kmem_free(busyp);
|
|
}
|