diff --git a/fs/jffs/jffs_fm.c b/fs/jffs/jffs_fm.c
index 29b68d9..6aab317 100644
--- a/fs/jffs/jffs_fm.c
+++ b/fs/jffs/jffs_fm.c
@@ -17,6 +17,7 @@
  *
  */
 #include <linux/slab.h>
+#include <linux/err.h>
 #include <linux/blkdev.h>
 #include <linux/jffs.h>
 #include "jffs_fm.h"
@@ -104,7 +105,7 @@
 
 	mtd = get_mtd_device(NULL, unit);
 
-	if (!mtd) {
+	if (IS_ERR(mtd)) {
 		kfree(fmc);
 		DJM(no_jffs_fmcontrol--);
 		return NULL;
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index bc4b810..590f60a 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -17,6 +17,7 @@
 #include <linux/init.h>
 #include <linux/list.h>
 #include <linux/fs.h>
+#include <linux/err.h>
 #include <linux/mount.h>
 #include <linux/jffs2.h>
 #include <linux/pagemap.h>
@@ -184,9 +185,9 @@
 	struct mtd_info *mtd;
 
 	mtd = get_mtd_device(NULL, mtdnr);
-	if (!mtd) {
+	if (IS_ERR(mtd)) {
 		D1(printk(KERN_DEBUG "jffs2: MTD device #%u doesn't appear to exist\n", mtdnr));
-		return -EINVAL;
+		return PTR_ERR(mtd);
 	}
 
 	return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt);
@@ -221,7 +222,7 @@
 			D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name+4));
 			for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) {
 				mtd = get_mtd_device(NULL, mtdnr);
-				if (mtd) {
+				if (!IS_ERR(mtd)) {
 					if (!strcmp(mtd->name, dev_name+4))
 						return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt);
 					put_mtd_device(mtd);