On Fri 11-11-16 13:25:47, Ross Zwisler wrote: > On Tue, Nov 08, 2016 at 12:08:12PM +0100, Jan Kara wrote: > > Currently mapping of blocks for DAX writes happen with > > EXT4_GET_BLOCKS_PRE_IO flag set. That has a result that each > > ext4_map_blocks() call creates a separate written extent, although it > > could be merged to the neighboring extents in the extent tree. The > > reason for using this flag is that in case the extent is unwritten, we > > need to convert it to written one and zero it out. However this "convert > > mapped range to written" operation is already implemented by > > ext4_map_blocks() for the case of data writes into unwritten extent. So > > just use flags for that mode of operation, simplify the code, and avoid > > unnecessary split extents. > > > > Signed-off-by: Jan Kara <jack@xxxxxxx> > > The code that this patch modifies was just introduced in the previous patch. > Is there a reason to keep both patches, or would it be cleaner just to squash > them and have one patch that introduces the code as you intend for it to end > up? Well, the previous patch just mostly moved the block allocation logic from dedicated DAX get_block function into iomap_begin(). This patch changes the block allocation logic so I prefer to keep them separate - mostly for the sake of documenting the change how allocation of blocks for DAX works in the changelog. Honza -- Jan Kara <jack@xxxxxxxx> 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
