diff options
| author | Mike Lockwood <lockwood@android.com> | 2008-03-15 13:29:36 -0400 |
|---|---|---|
| committer | Arve Hjønnevåg <arve@android.com> | 2013-07-01 13:40:20 -0700 |
| commit | 68d0e19e91b0904a707073a20a2edd63b9b2d264 (patch) | |
| tree | 00a10cbc935dcfe3797949cde9a3b187bbec1777 /fs/fat | |
| parent | 5a5f2f9219cf1df0cbd14542c5c709e34653d7f9 (diff) | |
FAT: Add new ioctl VFAT_IOCTL_GET_VOLUME_ID for reading the volume ID.
Signed-off-by: Brian Swetland <swetland@google.com>
Diffstat (limited to 'fs/fat')
| -rw-r--r-- | fs/fat/dir.c | 9 | ||||
| -rw-r--r-- | fs/fat/fat.h | 1 | ||||
| -rw-r--r-- | fs/fat/inode.c | 9 |
3 files changed, 19 insertions, 0 deletions
diff --git a/fs/fat/dir.c b/fs/fat/dir.c index 7a6f02caf286..ddfa4529e6ea 100644 --- a/fs/fat/dir.c +++ b/fs/fat/dir.c @@ -776,6 +776,13 @@ static int fat_ioctl_readdir(struct inode *inode, struct file *filp, return ret; } +static int fat_ioctl_volume_id(struct inode *dir) +{ + struct super_block *sb = dir->i_sb; + struct msdos_sb_info *sbi = MSDOS_SB(sb); + return sbi->vol_id; +} + static long fat_dir_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -792,6 +799,8 @@ static long fat_dir_ioctl(struct file *filp, unsigned int cmd, short_only = 0; both = 1; break; + case VFAT_IOCTL_GET_VOLUME_ID: + return fat_ioctl_volume_id(inode); default: return fat_generic_ioctl(filp, cmd, arg); } diff --git a/fs/fat/fat.h b/fs/fat/fat.h index 21664fcf3616..8180ecef59fc 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -86,6 +86,7 @@ struct msdos_sb_info { const void *dir_ops; /* Opaque; default directory operations */ int dir_per_block; /* dir entries per block */ int dir_per_block_bits; /* log2(dir_per_block) */ + unsigned long vol_id; /* volume ID */ int fatent_shift; struct fatent_operations *fatent_ops; diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 5d4513cb1b3c..a14dd4c0528a 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -1252,6 +1252,7 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, struct inode *fsinfo_inode = NULL; struct buffer_head *bh; struct fat_boot_sector *b; + struct fat_boot_bsx *bsx; struct msdos_sb_info *sbi; u16 logical_sector_size; u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors; @@ -1398,6 +1399,8 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, goto out_fail; } + bsx = (struct fat_boot_bsx *)(bh->b_data + FAT32_BSX_OFFSET); + fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data; if (!IS_FSINFO(fsinfo)) { fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: " @@ -1413,8 +1416,14 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat, } brelse(fsinfo_bh); + } else { + bsx = (struct fat_boot_bsx *)(bh->b_data + FAT16_BSX_OFFSET); } + /* interpret volume ID as a little endian 32 bit integer */ + sbi->vol_id = (((u32)bsx->vol_id[0]) | ((u32)bsx->vol_id[1] << 8) | + ((u32)bsx->vol_id[2] << 16) | ((u32)bsx->vol_id[3] << 24)); + sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry); sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1; |