From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Marzinski Date: Wed, 2 May 2007 09:44:03 -0500 Subject: [Cluster-devel] [GFS2 PATCH] flush the glock completely in inode_go_sync Message-ID: <20070502144403.GC23026@ether.msp.redhat.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Fix for bz #231910 When filemap_fdatawrite() is called on the inode mapping in data=ordered mode, it will add the glock to the log. In inode_go_sync(), if you do the gfs2_log_flush() before this, after the filemap_fdatawrite() call, the glock and its associated data buffers will be on the log again. This means you can demote a lock from exclusive, without having it flushed from the log. The attached patch simply moves the gfs2_log_flush up to after the filemap_fdatawrite() call. Originally, I tried moving the gfs2_log_flush to after gfs2_meta_sync(), but that caused me to trip the following assert. GFS2: fsid=cypher-36:test.0: fatal: assertion "!buffer_busy(bh)" failed GFS2: fsid=cypher-36:test.0: function = gfs2_ail_empty_gl, file = fs/gfs2/glops.c, line = 61 It appears that gfs2_log_flush() puts some of the glocks buffers in the busy state and the filemap_fdatawrite() call is necessary to flush them. This makes me worry slightly that a related problem could happen because of moving the gfs2_log_flush() after the initial filemap_fdatawrite(), but I assume that gfs2_ail_empty_gl() would catch that case as well. Signed-off-by: Benjamin E. Marzinski -------------- next part -------------- diff -urpN --exclude-from=gfs2-2.6-nmw-070416-clean/Documentation/dontdiff gfs2-2.6-nmw-070416-clean/fs/gfs2/glops.c gfs2-2.6-nmw-070416-test/fs/gfs2/glops.c --- gfs2-2.6-nmw-070416-clean/fs/gfs2/glops.c 2007-04-16 12:37:32.000000000 -0500 +++ gfs2-2.6-nmw-070416-test/fs/gfs2/glops.c 2007-04-29 11:37:55.000000000 -0500 @@ -156,9 +156,9 @@ static void inode_go_sync(struct gfs2_gl ip = NULL; if (test_bit(GLF_DIRTY, &gl->gl_flags)) { - gfs2_log_flush(gl->gl_sbd, gl); if (ip) filemap_fdatawrite(ip->i_inode.i_mapping); + gfs2_log_flush(gl->gl_sbd, gl); gfs2_meta_sync(gl); if (ip) { struct address_space *mapping = ip->i_inode.i_mapping;