• Herbert Poetzl's avatar
    JFS: ext2 inode attributes for jfs · fa3241d2
    Herbert Poetzl authored
    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
    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
    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: default avatarHerbert Poetzl <herbert@13thfloor.at>
    Signed-off-by: default avatarDave Kleikamp <shaggy@austin.ibm.com>
file.c 3.26 KB