Fix debugfs_create_file's error checking method for arch/sh/mm/

debugfs_create_file() returns NULL if an error occurs, returns -ENODEV
when debugfs is not enabled in the kernel.
Signed-off-by: NZhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/mm/cache-debugfs.c

@@ -130,12 +130,18 @@ static int __init cache_debugfs_init(void)
 	dcache_dentry = debugfs_create_file("dcache", S_IRUSR, sh_debugfs_root,
 					    (unsigned int *)CACHE_TYPE_DCACHE,
 					    &cache_debugfs_fops);
+	if (!dcache_dentry)
+		return -ENOMEM;
 	if (IS_ERR(dcache_dentry))
 		return PTR_ERR(dcache_dentry);
 
 	icache_dentry = debugfs_create_file("icache", S_IRUSR, sh_debugfs_root,
 					    (unsigned int *)CACHE_TYPE_ICACHE,
 					    &cache_debugfs_fops);
+	if (!icache_dentry) {
+		debugfs_remove(dcache_dentry);
+		return -ENOMEM;
+	}
 	if (IS_ERR(icache_dentry)) {
 		debugfs_remove(dcache_dentry);
 		return PTR_ERR(icache_dentry);

arch/sh/mm/pmb.c

@@ -394,6 +394,8 @@ static int __init pmb_debugfs_init(void)
 
 	dentry = debugfs_create_file("pmb", S_IFREG | S_IRUGO,
 				     sh_debugfs_root, NULL, &pmb_debugfs_fops);
+	if (!dentry)
+		return -ENOMEM;
 	if (IS_ERR(dentry))
 		return PTR_ERR(dentry);