From: Dave Chinner <dchinner@xxxxxxxxxx>
It currently either returns the cached filestream AG or it looks up
a new one. It has to be verified on return, which means the
returning code then might have to look up a new AG anyway.
Merge the initial lookup functionality so that we only need to do a
single pick loop on lookup or verification failure.
This does make xfs_filestream_select_ag() messier and I've ignored
the long lines, because it's got to get worse before it can get
better...
Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
---
fs/xfs/xfs_filestream.c | 140 +++++++++++++++++-----------------------
1 file changed, 59 insertions(+), 81 deletions(-)
diff --git a/fs/xfs/xfs_filestream.c b/fs/xfs/xfs_filestream.c
index 458df92fd9a6..996191273ea0 100644
--- a/fs/xfs/xfs_filestream.c
+++ b/fs/xfs/xfs_filestream.c
@@ -258,55 +258,6 @@ xfs_filestream_get_parent(
return dir ? XFS_I(dir) : NULL;
}
-/*
- * Find the right allocation group for a file, either by finding an
- * existing file stream or creating a new one.
- *
- * Returns NULLAGNUMBER in case of an error.
- */
-static xfs_agnumber_t
-xfs_filestream_lookup_ag(
- struct xfs_inode *ip)
-{
- struct xfs_mount *mp = ip->i_mount;
- struct xfs_inode *pip = NULL;
- xfs_agnumber_t startag, ag = NULLAGNUMBER;
- struct xfs_mru_cache_elem *mru;
-
- ASSERT(S_ISREG(VFS_I(ip)->i_mode));
-
- pip = xfs_filestream_get_parent(ip);
- if (!pip)
- return NULLAGNUMBER;
-
- mru = xfs_mru_cache_lookup(mp->m_filestream, pip->i_ino);
- if (mru) {
- ag = container_of(mru, struct xfs_fstrm_item, mru)->ag;
- xfs_mru_cache_done(mp->m_filestream);
-
- trace_xfs_filestream_lookup(mp, ip->i_ino, ag);
- goto out;
- }
-
- /*
- * Set the starting AG using the rotor for inode32, otherwise
- * use the directory inode's AG.
- */
- if (xfs_is_inode32(mp)) {
- xfs_agnumber_t rotorstep = xfs_rotorstep;
- startag = (mp->m_agfrotor / rotorstep) % mp->m_sb.sb_agcount;
- mp->m_agfrotor = (mp->m_agfrotor + 1) %
- (mp->m_sb.sb_agcount * rotorstep);
- } else
- startag = XFS_INO_TO_AGNO(mp, pip->i_ino);
-
- if (xfs_filestream_pick_ag(pip, startag, &ag, 0, 0))
- ag = NULLAGNUMBER;
-out:
- xfs_irele(pip);
- return ag;
-}
-
/*
* Pick a new allocation group for the current file and its file stream.
*
@@ -372,52 +323,79 @@ xfs_filestream_select_ag(
{
struct xfs_mount *mp = ap->ip->i_mount;
struct xfs_perag *pag;
- xfs_agnumber_t start_agno = xfs_filestream_lookup_ag(ap->ip);
+ struct xfs_inode *pip = NULL;
+ xfs_agnumber_t agno = NULLAGNUMBER;
+ struct xfs_mru_cache_elem *mru;
int error;
- /* Determine the initial block number we will target for allocation. */
- if (start_agno == NULLAGNUMBER)
- start_agno = 0;
- ap->blkno = XFS_AGB_TO_FSB(args->mp, start_agno, 0);
- xfs_bmap_adjacent(ap);
args->total = ap->total;
+ *blen = 0;
- pag = xfs_perag_grab(mp, start_agno);
- if (pag) {
- error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
- xfs_perag_rele(pag);
- if (error) {
- if (error != -EAGAIN)
- return error;
- *blen = 0;
- }
+ pip = xfs_filestream_get_parent(ap->ip);
+ if (!pip) {
+ agno = 0;
+ goto new_ag;
}
- if (*blen < args->maxlen) {
- xfs_agnumber_t agno = start_agno;
+ mru = xfs_mru_cache_lookup(mp->m_filestream, pip->i_ino);
+ if (mru) {
+ agno = container_of(mru, struct xfs_fstrm_item, mru)->ag;
+ xfs_mru_cache_done(mp->m_filestream);
- error = xfs_filestream_new_ag(ap, &agno);
- if (error)
- return error;
- if (agno == NULLAGNUMBER)
- goto out_select;
+ trace_xfs_filestream_lookup(mp, ap->ip->i_ino, start_agno);
+ xfs_irele(pip);
+
+ ap->blkno = XFS_AGB_TO_FSB(args->mp, start_agno, 0);
+ xfs_bmap_adjacent(ap);
pag = xfs_perag_grab(mp, agno);
- if (!pag)
+ if (pag) {
+ error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
+ xfs_perag_rele(pag);
+ if (error) {
+ if (error != -EAGAIN)
+ return error;
+ *blen = 0;
+ }
+ }
+ if (*blen >= args->maxlen)
goto out_select;
+ } else if (xfs_is_inode32(mp)) {
+ xfs_agnumber_t rotorstep = xfs_rotorstep;
+ agno = (mp->m_agfrotor / rotorstep) %
+ mp->m_sb.sb_agcount;
+ mp->m_agfrotor = (mp->m_agfrotor + 1) %
+ (mp->m_sb.sb_agcount * rotorstep);
+ xfs_irele(pip);
+ } else {
+ agno = XFS_INO_TO_AGNO(mp, pip->i_ino);
+ xfs_irele(pip);
+ }
- error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
- xfs_perag_rele(pag);
- if (error) {
- if (error != -EAGAIN)
- return error;
- *blen = 0;
- }
- start_agno = agno;
+new_ag:
+ ap->blkno = XFS_AGB_TO_FSB(args->mp, agno, 0);
+ xfs_bmap_adjacent(ap);
+
+ error = xfs_filestream_new_ag(ap, &agno);
+ if (error)
+ return error;
+ if (agno == NULLAGNUMBER)
+ goto out_select;
+
+ pag = xfs_perag_grab(mp, agno);
+ if (!pag)
+ goto out_select;
+
+ error = xfs_bmap_longest_free_extent(pag, args->tp, blen);
+ xfs_perag_rele(pag);
+ if (error) {
+ if (error != -EAGAIN)
+ return error;
+ *blen = 0;
}
out_select:
- ap->blkno = XFS_AGB_TO_FSB(mp, start_agno, 0);
+ ap->blkno = XFS_AGB_TO_FSB(mp, agno, 0);
return 0;
}
--
2.35.1
