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Message-Id: <20090825182613.740162763@bombadil.infradead.org>
Date: Tue, 25 Aug 2009 14:21:42 -0400
From: Christoph Hellwig <hch@infradead.org>
Subject: [PATCH 8/9] xfs: switch to NOFS allocation under i_lock in
	xfs_readlink_bmap
References: <20090825182134.299870049@bombadil.infradead.org>
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xfs_readlink_bmap is 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>

Index: linux-2.6/fs/xfs/xfs_vnodeops.c
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_vnodeops.c	2009-07-18 20:29:59.041657600 +0200
+++ linux-2.6/fs/xfs/xfs_vnodeops.c	2009-07-18 20:31:22.964535322 +0200
@@ -547,7 +547,9 @@ xfs_readlink_bmap(
 		d = XFS_FSB_TO_DADDR(mp, mval[n].br_startblock);
 		byte_cnt = XFS_FSB_TO_B(mp, mval[n].br_blockcount);
 
-		bp = xfs_buf_read(mp->m_ddev_targp, d, BTOBB(byte_cnt), 0);
+		bp = xfs_buf_read_flags(mp->m_ddev_targp, d, BTOBB(byte_cnt),
+					XBF_LOCK | XBF_MAPPED |
+					XBF_DONT_BLOCK);
 		error = XFS_BUF_GETERROR(bp);
 		if (error) {
 			xfs_ioerror_alert("xfs_readlink",

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