leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

xfs: split xfs_bmap_btalloc

Browse Source 
Split out the nullfb case into a separate function to reduce the stack
footprint and make the code more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
This commit is contained in:
Christoph Hellwig 2010-02-15 23:34:42 +00:00 committed by Alex Elder
parent f7008d0aeb
commit c467c049e7
1 changed files with 119 additions and 101 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

220
fs/xfs/xfs_bmap.c
View File

@ -2549,6 +2549,121 @@ xfs_bmap_rtalloc(
return 0;
}
STATIC int
xfs_bmap_btalloc_nullfb(
struct xfs_bmalloca *ap,
struct xfs_alloc_arg *args,
xfs_extlen_t *blen)
{
struct xfs_mount *mp = ap->ip->i_mount;
struct xfs_perag *pag;
xfs_agnumber_t ag, startag;
int notinit = 0;
int error;
if (ap->userdata && xfs_inode_is_filestream(ap->ip))
args->type = XFS_ALLOCTYPE_NEAR_BNO;
else
args->type = XFS_ALLOCTYPE_START_BNO;
args->total = ap->total;
/*
* Search for an allocation group with a single extent large enough
* for the request. If one isn't found, then adjust the minimum
* allocation size to the largest space found.
*/
startag = ag = XFS_FSB_TO_AGNO(mp, args->fsbno);
if (startag == NULLAGNUMBER)
startag = ag = 0;
pag = xfs_perag_get(mp, ag);
while (*blen < ap->alen) {
if (!pag->pagf_init) {
error = xfs_alloc_pagf_init(mp, args->tp, ag,
XFS_ALLOC_FLAG_TRYLOCK);
if (error) {
xfs_perag_put(pag);
return error;
}
}
/*
* See xfs_alloc_fix_freelist...
*/
if (pag->pagf_init) {
xfs_extlen_t longest;
longest = xfs_alloc_longest_free_extent(mp, pag);
if (*blen < longest)
*blen = longest;
} else
notinit = 1;
if (xfs_inode_is_filestream(ap->ip)) {
if (*blen >= ap->alen)
break;
if (ap->userdata) {
/*
* If startag is an invalid AG, we've
* come here once before and
* xfs_filestream_new_ag picked the
* best currently available.
*
* Don't continue looping, since we
* could loop forever.
*/
if (startag == NULLAGNUMBER)
break;
error = xfs_filestream_new_ag(ap, &ag);
xfs_perag_put(pag);
if (error)
return error;
/* loop again to set 'blen'*/
startag = NULLAGNUMBER;
pag = xfs_perag_get(mp, ag);
continue;
}
}
if (++ag == mp->m_sb.sb_agcount)
ag = 0;
if (ag == startag)
break;
xfs_perag_put(pag);
pag = xfs_perag_get(mp, ag);
}
xfs_perag_put(pag);
/*
* Since the above loop did a BUF_TRYLOCK, it is
* possible that there is space for this request.
*/
if (notinit || *blen < ap->minlen)
args->minlen = ap->minlen;
/*
* If the best seen length is less than the request
* length, use the best as the minimum.
*/
else if (*blen < ap->alen)
args->minlen = *blen;
/*
* Otherwise we've seen an extent as big as alen,
* use that as the minimum.
*/
else
args->minlen = ap->alen;
/*
* set the failure fallback case to look in the selected
* AG as the stream may have moved.
*/
if (xfs_inode_is_filestream(ap->ip))
ap->rval = args->fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
return 0;
}
STATIC int
xfs_bmap_btalloc(
xfs_bmalloca_t *ap) /* bmap alloc argument struct */
@ -2556,16 +2671,13 @@ xfs_bmap_btalloc(
xfs_mount_t *mp; /* mount point structure */
xfs_alloctype_t atype = 0; /* type for allocation routines */
xfs_extlen_t align; /* minimum allocation alignment */
xfs_agnumber_t ag;
xfs_agnumber_t fb_agno; /* ag number of ap->firstblock */
xfs_agnumber_t startag;
xfs_agnumber_t ag;
xfs_alloc_arg_t args;
xfs_extlen_t blen;
xfs_extlen_t nextminlen = 0;
xfs_perag_t *pag;
int nullfb; /* true if ap->firstblock isn't set */
int isaligned;
int notinit;
int tryagain;
int error;
@ -2612,103 +2724,9 @@ xfs_bmap_btalloc(
args.firstblock = ap->firstblock;
blen = 0;
if (nullfb) {
if (ap->userdata && xfs_inode_is_filestream(ap->ip))
args.type = XFS_ALLOCTYPE_NEAR_BNO;
else
args.type = XFS_ALLOCTYPE_START_BNO;
args.total = ap->total;
/*
* Search for an allocation group with a single extent
* large enough for the request.
*
* If one isn't found, then adjust the minimum allocation
* size to the largest space found.
*/
startag = ag = XFS_FSB_TO_AGNO(mp, args.fsbno);
if (startag == NULLAGNUMBER)
startag = ag = 0;
notinit = 0;
pag = xfs_perag_get(mp, ag);
while (blen < ap->alen) {
if (!pag->pagf_init &&
(error = xfs_alloc_pagf_init(mp, args.tp,
ag, XFS_ALLOC_FLAG_TRYLOCK))) {
xfs_perag_put(pag);
return error;
}
/*
* See xfs_alloc_fix_freelist...
*/
if (pag->pagf_init) {
xfs_extlen_t longest;
longest = xfs_alloc_longest_free_extent(mp, pag);
if (blen < longest)
blen = longest;
} else
notinit = 1;
if (xfs_inode_is_filestream(ap->ip)) {
if (blen >= ap->alen)
break;
if (ap->userdata) {
/*
* If startag is an invalid AG, we've
* come here once before and
* xfs_filestream_new_ag picked the
* best currently available.
*
* Don't continue looping, since we
* could loop forever.
*/
if (startag == NULLAGNUMBER)
break;
error = xfs_filestream_new_ag(ap, &ag);
xfs_perag_put(pag);
if (error)
return error;
/* loop again to set 'blen'*/
startag = NULLAGNUMBER;
pag = xfs_perag_get(mp, ag);
continue;
}
}
if (++ag == mp->m_sb.sb_agcount)
ag = 0;
if (ag == startag)
break;
xfs_perag_put(pag);
pag = xfs_perag_get(mp, ag);
}
xfs_perag_put(pag);
/*
* Since the above loop did a BUF_TRYLOCK, it is
* possible that there is space for this request.
*/
if (notinit || blen < ap->minlen)
args.minlen = ap->minlen;
/*
* If the best seen length is less than the request
* length, use the best as the minimum.
*/
else if (blen < ap->alen)
args.minlen = blen;
/*
* Otherwise we've seen an extent as big as alen,
* use that as the minimum.
*/
else
args.minlen = ap->alen;
/*
* set the failure fallback case to look in the selected
* AG as the stream may have moved.
*/
if (xfs_inode_is_filestream(ap->ip))
ap->rval = args.fsbno = XFS_AGB_TO_FSB(mp, ag, 0);
error = xfs_bmap_btalloc_nullfb(ap, &args, &blen);
if (error)
return error;
} else if (ap->low) {
if (xfs_inode_is_filestream(ap->ip))
args.type = XFS_ALLOCTYPE_FIRST_AG;