On 13/09/2015 13:44, Bob Liu wrote:
I may misunderstood here. But I think same changes are also required even if backend supports indirect grant when frontend is using 64KB page granularity. Else 1) How to set up the grant map for requests in domU? The minimum segment buffer size in a request is PAGE_SIZE(64KB) while grant is 4KB based. 2) Codes like below in blkback.c may not work correctly? if ((req->u.rw.seg[i].last_sect >= (PAGE_SIZE >> 9)) || Because PAGE_SIZE in backend is 4KB, while the written value by domU is 64KB based.
As mention in my cover letter, this patch is not self-sufficient to support 64KB guest. It's a follow-up of the 64KB page granularity support I sent on the ML (the new version was sent earlier this week [1]).
One of the patch [2] is taking care of breaking down the I/O request in multiple 4KB segment that will be used in the ring request. You may want to give a look to this patch before looking to this series.
Regards, [1] https://lwn.net/Articles/656797/ [2] http://www.spinics.net/lists/arm-kernel/msg430468.html -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
