xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_get

xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken
in reclaim context so all allocations under it must avoid recursions into
the filesystem.

Reported by the new reclaim context tracing in lockdep.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Felix Blyakher <felixb@sgi.com>

diff --git a/fs/xfs/xfs_attr.c b/fs/xfs/xfs_attr.c
index bfb5837..4ece190 100644 (file)
--- a/fs/xfs/xfs_attr.c
+++ b/fs/xfs/xfs_attr.c
@@ -2010,7 +2010,9 @@ xfs_attr_rmtval_get(xfs_da_args_t *args)
                        dblkno = XFS_FSB_TO_DADDR(mp, map[i].br_startblock);
                        blkcnt = XFS_FSB_TO_BB(mp, map[i].br_blockcount);
                        error = xfs_read_buf(mp, mp->m_ddev_targp, dblkno,
-                                            blkcnt, XFS_BUF_LOCK, &bp);
+                                            blkcnt,
+                                            XFS_BUF_LOCK | XBF_DONT_BLOCK,
+                                            &bp);
                        if (error)
                                return(error);