FAT_VALID_MEDIA(): remove pointless test

commit 73f20e58b1d586e9f6d3ddc3aad872829aca7743 upstream

The on-disk media specification field in FAT is only 8-bits, so testing for
<=0xff is pointless, and can generate a "comparison is always true due to
limited range of data type" warning.

While we're there, convert FAT_VALID_MEDIA() into a C function - the present
implementation is buggy: it generates either one or two references to its
argument.

Cc: Frank Seidel <fseidel@suse.de>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 53f3cf62b7c18c945bdcc3caaddf9466a91ca391..98f0e874c5e19f6740ae677d16073bb87a1d2ebd 100644 (file)
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -1208,7 +1208,7 @@ int fat_fill_super(struct super_block *sb, void *data, int silent,
         */
 
        media = b->media;
-       if (!FAT_VALID_MEDIA(media)) {
+       if (!fat_valid_media(media)) {
                if (!silent)
                        printk(KERN_ERR "FAT: invalid media value (0x%02x)\n",
                               media);

diff --git a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h
index f950921523f55316e2ede3f73c7e4a5d22e98b34..20277adf16cb6a76515d494f1d21f6d5e6218a50 100644 (file)
--- a/include/linux/msdos_fs.h
+++ b/include/linux/msdos_fs.h
@@ -58,7 +58,11 @@
 #define MSDOS_DOTDOT   "..         "   /* "..", padded to MSDOS_NAME chars */
 
 /* media of boot sector */
-#define FAT_VALID_MEDIA(x)     ((0xF8 <= (x) && (x) <= 0xFF) || (x) == 0xF0)
+static inline int fat_valid_media(u8 media)
+{
+       return 0xf8 <= media || media == 0xf0;
+}
+
 #define FAT_FIRST_ENT(s, x)    ((MSDOS_SB(s)->fat_bits == 32 ? 0x0FFFFF00 : \
        MSDOS_SB(s)->fat_bits == 16 ? 0xFF00 : 0xF00) | (x))