From 2035e776050aea57fb5255557216473e82793f2c Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 18 Apr 2011 17:29:14 -0400 Subject: ext4: check for ext[23] file system features when mounting as ext[23] Provide better emulation for ext[23] mode by enforcing that the file system does not have any unsupported file system features as defined by ext[23] when emulating the ext[23] file system driver when CONFIG_EXT4_USE_FOR_EXT23 is defined. This causes the file system type information in /proc/mounts to be correct for the automatically mounted root file system. This also means that "mount -t ext2 /dev/sda /mnt" will fail if /dev/sda contains an ext3 or ext4 file system, just as one would expect if the original ext2 file system driver were in use. Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'fs/ext4/ext4.h') diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 4daaf2b753f4..076c5d212a3c 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1351,6 +1351,21 @@ static inline void ext4_clear_state_flags(struct ext4_inode_info *ei) #define EXT4_FEATURE_INCOMPAT_EA_INODE 0x0400 /* EA in inode */ #define EXT4_FEATURE_INCOMPAT_DIRDATA 0x1000 /* data in dirent */ +#define EXT2_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR +#define EXT2_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \ + EXT4_FEATURE_INCOMPAT_META_BG) +#define EXT2_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \ + EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \ + EXT4_FEATURE_RO_COMPAT_BTREE_DIR) + +#define EXT3_FEATURE_COMPAT_SUPP EXT4_FEATURE_COMPAT_EXT_ATTR +#define EXT3_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \ + EXT4_FEATURE_INCOMPAT_RECOVER| \ + EXT4_FEATURE_INCOMPAT_META_BG) +#define EXT3_FEATURE_RO_COMPAT_SUPP (EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER| \ + EXT4_FEATURE_RO_COMPAT_LARGE_FILE| \ + EXT4_FEATURE_RO_COMPAT_BTREE_DIR) + #define EXT4_FEATURE_COMPAT_SUPP EXT2_FEATURE_COMPAT_EXT_ATTR #define EXT4_FEATURE_INCOMPAT_SUPP (EXT4_FEATURE_INCOMPAT_FILETYPE| \ EXT4_FEATURE_INCOMPAT_RECOVER| \ -- cgit v1.2.3