On Tue, Jul 21, 2020 at 06:01:43PM +0200, Christoph Hellwig wrote: > On Tue, Jul 21, 2020 at 08:59:25AM -0700, Darrick J. Wong wrote: > > In the comment that precedes iomap_dio_rw() for the iomap version, > > maybe let's just do that.. > > > ``direct_IO`` > > called by the generic read/write routines to perform direct_IO - > > that is IO requests which bypass the page cache and transfer > > data directly between the storage and the application's address > > space. This function can return -ENOTBLK to signal that it is > > necessary to fallback to buffered IO. Note that > > blockdev_direct_IO and variants can also return -ENOTBLK. > > ->direct_IO is not used for iomap and various other implementations. > In fact it is a horrible hack that I've been trying to get rid of > for a while. Agreed, but for now there are still a number of fses who are still on the old directio code; let's try to keep the drainbamage/confusion potential to a minimum so it doesn't spread to our iomap shinyness. :) --D
