[PATCH 1/4] xfs: only lock the rt bitmap inode once per allocation

[kdasu]

Currently both xfs_rtpick_extent and xfs_rtallocate_extent call
xfs_trans_iget to grab and lock the rt bitmap inode, which results in a
deadlock since the removal of the lock recursion counters in commit

        "xfs: simplify inode to transaction joining"

Fix this by acquiring and locking the inode in xfs_bmap_rtalloc before
calling into xfs_rtpick_extent and xfs_rtallocate_extent.

Signed-off-by: Christoph Hellwig <hch at lst.de>
Signed-off-by: Alex Elder <aelder at sgi.com>
Signed-off-by: Kamal Dasu <kdasu.kdev at gmail.com>
---
 fs/xfs/xfs_bmap.c    |   11 +++++++++++
 fs/xfs/xfs_rtalloc.c |   34 +++++++++++++---------------------
 2 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index 4111cd3..9d9970b 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -2316,6 +2316,7 @@ xfs_bmap_rtalloc(
        xfs_extlen_t    prod = 0;       /* product factor for allocators */
        xfs_extlen_t    ralen = 0;      /* realtime allocation length */
        xfs_extlen_t    align;          /* minimum allocation alignment */
+       xfs_inode_t     *ip;            /* bitmap incore inode */
        xfs_rtblock_t   rtb;
kdasu at kdasu-VirtualBox:~/linux-2.6$ more
0001-xfs-only-lock-the-rt-bitmap-inode-once-per-allocatio.patch