On Wed 08-01-14 18:37:52, Ted Tso wrote: > On Wed, Jan 08, 2014 at 11:14:30PM +0100, Jan Kara wrote: > > So when I was thinking about this (already couple of years ago) the thing > > which stopped me was the question at which layer we should do the > > translation. Ideally we would need something at submit_bh() level but just > > wrapping submit_bh() calls inside ext4 isn't enough for stuff like symlinks > > or journalled data... Do you have any thoughts on that? > > I think there are two interfaces that should handle nearly all of our > journal block mapping needs. The functions that issue bio requests > directly tend to use ext4_get_block*() functions, and functions which > use the buffer cache uses submit_bh() (typically via ext4_getblk). > There will probably be a few exceptions, but I don't think this should > be an intractable problem. Surely not intractable :) It was just ugly. But you are right that hooking in ext4_map_blocks() and then special-casing the few cases where we get the block number by different means (xattrs, inode table, group descriptor, superblock, traversal of extent tree & indirect block tree) should be reasonably elegant. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
