On Thu, Dec 06, 2018 at 12:14:29PM -0700, Jens Axboe wrote: > On 12/6/18 12:11 PM, Jeff Moyer wrote: > > Jens Axboe <axboe@xxxxxxxxx> writes: > > > >> From: Christoph Hellwig <hch@xxxxxx> > >> > >> Just call blk_poll on the iocb cookie, we can derive the block device > >> from the inode trivially. > > > > Does this work for multi-device file systems? > > It should, that's the whole purpose of having fops->iopoll. You should > be able to derive it from inode + cookie. It still assumes the whole I/O will got to a single device. For XFS this is always tree, but for btrfs this might mean I/O could need splitting if ->iopoll was to be supported there.
