On Wed, May 01, 2024 at 06:32:45PM +0530, Kanchan Joshi wrote: > Can you please tell what function(s) in bio data path that need this > conversion? > To me data path handling seems similar. Each cloned bio will lead to > some amount of data transfer to pinned user-memory. The same is > happening for meta transfer here. Well, everywhere. e.g. for direct I/O everything is just driven from the fs/direct-io.c and and fs/iomap/direct-io.c code without any knowledge in the underlying driver if data has been pinned (no bounce buffering in this case). Or for passthrough I/O none of the underlying logic knows about the pinning or bounce buffering, everything is handled in block/blk-map.c.