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>

1 files changed, 34 insertions, 3 deletions

diff --git a/fs/jfs/jfs_inode.c b/fs/jfs/jfs_inode.c
index 2af5efb..ae2772c 100644
--- a/fs/jfs/jfs_inode.c
+++ b/fs/jfs/jfs_inode.c
@@ -25,6 +25,26 @@
 #include "jfs_dinode.h"
 #include "jfs_debug.h"
 
+
+void jfs_set_inode_flags(struct inode *inode)
+{
+	unsigned int flags = JFS_IP(inode)->mode2;
+
+	inode->i_flags &= ~(S_IMMUTABLE | S_APPEND |
+		S_NOATIME | S_DIRSYNC | S_SYNC);
+
+	if (flags & JFS_IMMUTABLE_FL)
+		inode->i_flags |= S_IMMUTABLE;
+	if (flags & JFS_APPEND_FL)
+		inode->i_flags |= S_APPEND;
+	if (flags & JFS_NOATIME_FL)
+		inode->i_flags |= S_NOATIME;
+	if (flags & JFS_DIRSYNC_FL)
+		inode->i_flags |= S_DIRSYNC;
+	if (flags & JFS_SYNC_FL)
+		inode->i_flags |= S_SYNC;
+}
+
 /*
  * NAME:	ialloc()
  *
@@ -74,10 +94,20 @@ struct inode *ialloc(struct inode *parent, umode_t mode)
 	}
 
 	inode->i_mode = mode;
-	if (S_ISDIR(mode))
-		jfs_inode->mode2 = IDIRECTORY | mode;
+	/* inherit flags from parent */
+	jfs_inode->mode2 = JFS_IP(parent)->mode2 & JFS_FL_INHERIT;
+
+	if (S_ISDIR(mode)) {
+		jfs_inode->mode2 |= IDIRECTORY;
+		jfs_inode->mode2 &= ~JFS_DIRSYNC_FL;
+	}
+	else if (S_ISLNK(mode))
+		jfs_inode->mode2 &=
+			~(JFS_IMMUTABLE_FL|JFS_APPEND_FL);
 	else
-		jfs_inode->mode2 = INLINEEA | ISPARSE | mode;
+		jfs_inode->mode2 |= INLINEEA | ISPARSE;
+	jfs_inode->mode2 |= mode;
+
 	inode->i_blksize = sb->s_blocksize;
 	inode->i_blocks = 0;
 	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
@@ -98,6 +128,7 @@ struct inode *ialloc(struct inode *parent, umode_t mode)
 	jfs_inode->atlhead = 0;
 	jfs_inode->atltail = 0;
 	jfs_inode->xtlid = 0;
+	jfs_set_inode_flags(inode);
 
 	jfs_info("ialloc returns inode = 0x%p\n", inode);