From b443b77e4511a3fea2dfd7739120c69a6e80dd53 Mon Sep 17 00:00:00 2001 From: Oleksij Rempel Date: Thu, 7 Feb 2013 12:27:52 +1100 Subject: [PATCH] fat: add extended fileds to struct fat_boot_sector Later we will need "state" field to check if volume was cleanly unmounted. Signed-off-by: Oleksij Rempel Signed-off-by: OGAWA Hirofumi Signed-off-by: Andrew Morton --- fs/fat/inode.c | 8 ++++---- include/uapi/linux/msdos_fs.h | 36 +++++++++++++++++++++++++++-------- 2 files changed, 32 insertions(+), 12 deletions(-) diff --git a/fs/fat/inode.c b/fs/fat/inode.c index f8f491677a4a..4b4d4ef910f3 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -1298,17 +1298,17 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, sbi->prev_free = FAT_START_ENT; sb->s_maxbytes = 0xffffffff; - if (!sbi->fat_length && b->fat32_length) { + if (!sbi->fat_length && b->fat32.length) { struct fat_boot_fsinfo *fsinfo; struct buffer_head *fsinfo_bh; /* Must be FAT32 */ sbi->fat_bits = 32; - sbi->fat_length = le32_to_cpu(b->fat32_length); - sbi->root_cluster = le32_to_cpu(b->root_cluster); + sbi->fat_length = le32_to_cpu(b->fat32.length); + sbi->root_cluster = le32_to_cpu(b->fat32.root_cluster); /* MC - if info_sector is 0, don't multiply by 0 */ - sbi->fsinfo_sector = le16_to_cpu(b->info_sector); + sbi->fsinfo_sector = le16_to_cpu(b->fat32.info_sector); if (sbi->fsinfo_sector == 0) sbi->fsinfo_sector = 1; diff --git a/include/uapi/linux/msdos_fs.h b/include/uapi/linux/msdos_fs.h index 996719f82e28..b9f12450efe8 100644 --- a/include/uapi/linux/msdos_fs.h +++ b/include/uapi/linux/msdos_fs.h @@ -120,14 +120,34 @@ struct fat_boot_sector { __le32 hidden; /* hidden sectors (unused) */ __le32 total_sect; /* number of sectors (if sectors == 0) */ - /* The following fields are only used by FAT32 */ - __le32 fat32_length; /* sectors/FAT */ - __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ - __u8 version[2]; /* major, minor filesystem version */ - __le32 root_cluster; /* first cluster in root directory */ - __le16 info_sector; /* filesystem info sector */ - __le16 backup_boot; /* backup boot sector */ - __le16 reserved2[6]; /* Unused */ + union { + struct { + /* Extended BPB Fields for FAT16 */ + __u8 drive_number; /* Physical drive number */ + __u8 state; /* undocumented, but used + for mount state. */ + /* other fiealds are not added here */ + } fat16; + + struct { + /* only used by FAT32 */ + __le32 length; /* sectors/FAT */ + __le16 flags; /* bit 8: fat mirroring, + low 4: active fat */ + __u8 version[2]; /* major, minor filesystem + version */ + __le32 root_cluster; /* first cluster in + root directory */ + __le16 info_sector; /* filesystem info sector */ + __le16 backup_boot; /* backup boot sector */ + __le16 reserved2[6]; /* Unused */ + /* Extended BPB Fields for FAT32 */ + __u8 drive_number; /* Physical drive number */ + __u8 state; /* undocumented, but used + for mount state. */ + /* other fiealds are not added here */ + } fat32; + }; }; struct fat_boot_fsinfo { -- 2.39.5