xfs: split xfs_bmap_btalloc
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>
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 1869fb9..5c11e4d 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -2550,22 +2550,134 @@
}
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 */
{
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 @@
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;