diff options
| author | Darrick J. Wong <djwong@kernel.org> | 2024-12-02 10:57:30 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-12-19 18:13:08 +0100 |
| commit | 3b6616ffc99b82af387f144e5b6d7afd5fa26780 (patch) | |
| tree | 0fc733cd65d0072788778cf76ab3709dae689733 | |
| parent | 3e2f62d1d773fc3cb8d5f97353f04170c13099e4 (diff) | |
xfs: fix null bno_hint handling in xfs_rtallocate_rtg
commit af9f02457f461b23307fe826a37be61ba6e32c92 upstream.
xfs_bmap_rtalloc initializes the bno_hint variable to NULLRTBLOCK (aka
NULLFSBLOCK). If the allocation request is for a file range that's
adjacent to an existing mapping, it will then change bno_hint to the
blkno hint in the bmalloca structure.
In other words, bno_hint is either a rt block number, or it's all 1s.
Unfortunately, commit ec12f97f1b8a8f didn't take the NULLRTBLOCK state
into account, which means that it tries to translate that into a
realtime extent number. We then end up with an obnoxiously high rtx
number and pointlessly feed that to the near allocator. This often
fails and falls back to the by-size allocator. Seeing as we had no
locality hint anyway, this is a waste of time.
Fix the code to detect a lack of bno_hint correctly. This was detected
by running xfs/009 with metadir enabled and a 28k rt extent size.
Cc: <stable@vger.kernel.org> # v6.12
Fixes: ec12f97f1b8a8f ("xfs: make the rtalloc start hint a xfs_rtblock_t")
Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/xfs/xfs_rtalloc.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c index 3a2005a1e673..8caa55b81674 100644 --- a/fs/xfs/xfs_rtalloc.c +++ b/fs/xfs/xfs_rtalloc.c @@ -1295,7 +1295,7 @@ xfs_rtallocate( * For an allocation to an empty file at offset 0, pick an extent that * will space things out in the rt area. */ - if (bno_hint) + if (bno_hint != NULLFSBLOCK) start = xfs_rtb_to_rtx(args.mp, bno_hint); else if (initial_user_data) start = xfs_rtpick_extent(args.mp, tp, maxlen); |