[MTD] Fix !CONFIG_BLOCK compile for mtdsuper.c

As reported by Adrian Bunk, commit d5686b444ff3f72808d2b3fbd58672a86cdf38e7
(switch mtd and dm-table to lookup_bdev()) causes the following compile
error with CONFIG_BLOCK=n:

  CC      drivers/mtd/mtdsuper.o
drivers/mtd/mtdsuper.c: In function `get_sb_mtd':
drivers/mtd/mtdsuper.c:184: error: implicit declaration of function 'lookup_bdev'
drivers/mtd/mtdsuper.c:184: warning: assignment makes pointer from integer without a cast
drivers/mtd/mtdsuper.c:197: error: implicit declaration of function 'bdput'
make[3]: *** [drivers/mtd/mtdsuper.o] Error 1

Fix it by putting the block device lookup inside #ifdef CONFIG_BLOCK

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 12 insertions, 5 deletions

diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c
index 9b6af7e74a65..00d46e137b2a 100644
--- a/drivers/mtd/mtdsuper.c
+++ b/drivers/mtd/mtdsuper.c
@@ -125,8 +125,11 @@ int get_sb_mtd(struct file_system_type *fs_type, int flags,
                int (*fill_super)(struct super_block *, void *, int),
                struct vfsmount *mnt)
 {
+#ifdef CONFIG_BLOCK
         struct block_device *bdev;
-        int mtdnr, ret;
+        int ret, major;
+#endif
+        int mtdnr;
 
         if (!dev_name)
                 return -EINVAL;
@@ -178,6 +181,7 @@ int get_sb_mtd(struct file_system_type *fs_type, int flags,
                 }
         }
 
+#ifdef CONFIG_BLOCK
         /* try the old way - the hack where we allowed users to mount
          * /dev/mtdblock$(n) but didn't actually _use_ the blockdev
          */
@@ -190,22 +194,25 @@ int get_sb_mtd(struct file_system_type *fs_type, int flags,
         DEBUG(1, "MTDSB: lookup_bdev() returned 0\n");
 
         ret = -EINVAL;
-        if (MAJOR(bdev->bd_dev) != MTD_BLOCK_MAJOR)
-                goto not_an_MTD_device;
 
+        major = MAJOR(bdev->bd_dev);
         mtdnr = MINOR(bdev->bd_dev);
         bdput(bdev);
 
+        if (major != MTD_BLOCK_MAJOR)
+                goto not_an_MTD_device;
+
         return get_sb_mtd_nr(fs_type, flags, dev_name, data, mtdnr, fill_super,
                              mnt);
 
 not_an_MTD_device:
+#endif /* CONFIG_BLOCK */
+
         if (!(flags & MS_SILENT))
                 printk(KERN_NOTICE
                        "MTD: Attempt to mount non-MTD device \"%s\"\n",
                        dev_name);
-        bdput(bdev);
-        return ret;
+        return -EINVAL;
 }
 
 EXPORT_SYMBOL_GPL(get_sb_mtd);