GFS2: Use an IS_ERR test rather than a NULL test
authorJulien Brunel <brunel@diku.dk>
Mon, 1 Sep 2008 08:51:22 +0000 (10:51 +0200)
committerSteven Whitehouse <swhiteho@redhat.com>
Fri, 5 Sep 2008 13:19:44 +0000 (14:19 +0100)
commitbd1eb8818cc2c8ddab86be027ab43fb852942704
treeb072daf0c29f929217acc7a589b48c615da6b238
parentdff5257473ca1e05002809809f51f858e9a966fc
GFS2: Use an IS_ERR test rather than a NULL test

In case of error, the function gfs2_inode_lookup returns an
ERR pointer, but never returns a NULL pointer. So a NULL test that
necessarily comes after an IS_ERR test should be deleted, and a NULL
test that may come after a call to this function should be
strengthened by an IS_ERR test.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@match_bad_null_test@
expression x, E;
statement S1,S2;
@@
x = gfs2_inode_lookup(...)
... when != x = E
* if (x != NULL)
S1 else S2
// </smpl>

Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
fs/gfs2/inode.c