From mboxrd@z Thu Jan 1 00:00:00 1970 From: hch@lst.de (Christoph Hellwig) Date: Fri, 10 Nov 2017 05:54:18 +0100 Subject: [PATCH 4/7] nvme: implement multipath access to nvme subsystems In-Reply-To: <20171109212217.GA16454@redhat.com> References: <20171109174450.17142-1-hch@lst.de> <20171109174450.17142-5-hch@lst.de> <20171109212217.GA16454@redhat.com> Message-ID: <20171110045418.GB32408@lst.de> On Thu, Nov 09, 2017@04:22:17PM -0500, Mike Snitzer wrote: > Your 0th header speaks to the NVMe multipath IO path leveraging NVMe's > lack of partial completion but I think it'd be useful to have this > header (that actually gets committed) speak to it. There is a comment above blk_steal_bios to this respect, which is in the tree. > Also, the block core patch to introduce blk_steal_bios() already went in > but should there be a QUEUE_FLAG that gets set by drivers like NVMe that > don't support partial completion? > > This would make it easier for other future drivers to know whether they > can use a more optimized IO path. As-is there is not real need for this. But if you want to use a similar path in dm-multipath feel free to add the flag when needed.