fat: new inline functions to determine the FAT variant (32, 16 or 12)

This patch introduces 3 new inline functions - is_fat12, is_fat16 and
is_fat32, and replaces every occurrence in the code in which the FS
variant (whether this is FAT12, FAT16 or FAT32) was previously checked
using msdos_sb_info->fat_bits.

Link: http://lkml.kernel.org/r/1544990640-11604-4-git-send-email-carmeli.tamir@gmail.com
Signed-off-by: Carmeli Tamir <carmeli.tamir@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Carmeli Tamir
2019-01-03 15:28:00 -08:00
committed by Linus Torvalds
parent d19dc01618
commit 306790f75a
6 changed files with 39 additions and 22 deletions

View File

@@ -142,13 +142,32 @@ static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb)
return sb->s_fs_info;
}
/*
* Functions that determine the variant of the FAT file system (i.e.,
* whether this is FAT12, FAT16 or FAT32.
*/
static inline bool is_fat12(const struct msdos_sb_info *sbi)
{
return sbi->fat_bits == 12;
}
static inline bool is_fat16(const struct msdos_sb_info *sbi)
{
return sbi->fat_bits == 16;
}
static inline bool is_fat32(const struct msdos_sb_info *sbi)
{
return sbi->fat_bits == 32;
}
/* Maximum number of clusters */
static inline u32 max_fat(struct super_block *sb)
{
struct msdos_sb_info *sbi = MSDOS_SB(sb);
return sbi->fat_bits == 32 ? MAX_FAT32 :
sbi->fat_bits == 16 ? MAX_FAT16 : MAX_FAT12;
return is_fat32(sbi) ? MAX_FAT32 :
is_fat16(sbi) ? MAX_FAT16 : MAX_FAT12;
}
static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
@@ -266,7 +285,7 @@ static inline int fat_get_start(const struct msdos_sb_info *sbi,
const struct msdos_dir_entry *de)
{
int cluster = le16_to_cpu(de->start);
if (sbi->fat_bits == 32)
if (is_fat32(sbi))
cluster |= (le16_to_cpu(de->starthi) << 16);
return cluster;
}