FAT_VALID_MEDIA(): remove pointless test

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 <[email protected]> Acked-by: OGAWA Hirofumi <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
marcan · Apr 28, 2008 · 73f20e5 · 73f20e5
1 parent c7a6c4e
commit 73f20e5
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Showing 2 changed files with 6 additions and 2 deletions.
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
@@ -1215,7 +1215,7 @@ 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
@@ -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))