JFS: ext2 inode attributes for jfs
ext2 inode attributes with relevance for jfs:
'a' EXT2_APPEND_FL -> append only
'i' EXT2_IMMUTABLE_FL -> immutable file
's' EXT2_SECRM_FL -> zero file
'u' EXT2_UNRM_FL -> allow for unrm
'A' EXT2_NOATIME_FL -> no access time
'D' EXT2_DIRSYNC_FL -> dirsync
'S' EXT2_SYNC_FL -> sync
overview of jfs flags (partially for OS/2)
value (OS/2) Linux ext2 attrs
------------------------------------------------
0x00010000 IFJOURNAL -
0x00020000 ISPARSE used
0x00040000 INLINEEA used
0x00080000 - - JFS_NOATIME_FL
0x00100000 - - JFS_DIRSYNC_FL
0x00200000 - - JFS_SYNC_FL
0x00400000 - - JFS_SECRM_FL
0x00800000 ISWAPFILE - JFS_UNRM_FL
0x01000000 - - JFS_APPEND_FL
0x02000000 IREADONLY - JFS_IMMUTABLE_FL
0x04000000 IHIDDEN - -
0x08000000 ISYSTEM - -
0x10000000 - -
0x20000000 IDIRECTORY used
0x40000000 IARCHIVE -
0x80000000 INEWNAME -
the implementation is straight forward, except
for the fact that the attributes have to be mapped
to match with the ext2 ones to avoid a separate
tool for manipulating them (this could be avoided
when using a separate flag field in the on-disk
representation, but the overhead is minimal)
a special jfs_ioctl is added to allow for the new
JFS_IOC_GETFLAGS and JFS_IOC_SETFLAGS calls.
a helper function jfs_set_inode_flags() to transfer
the flags from the on-disk version to the inode
minor changes to allow flag inheritance on inode
creation, as well as a cleanup of the on-disk
flags (including the new ones)
beforementioned helper to map between ext2 and jfs
versions of the new flags ...
the JFS_SECRM_FL and JFS_UNRM_FL are not done yet
and I'm not 100% sure they are worth the effort,
the rest seems to work out of the box ...
Signed-off-by: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
7 files changed
