On Wed, Jun 11, 2014 at 7:09 PM, Matthew Wilcox <wi...@linux.intel.com> wrote: > On Wed, Jun 11, 2014 at 10:54:52AM -0600, Jens Axboe wrote: >> OK, so essentially any single request must be a virtually contig piece >> of memory. Is there any size limitations to how big this contig segment >> can be? > > The maximum size of an I/O is 65536 sectors. So on a 512-byte sector > device, that's 32MB, but on a 4k sector size device, that's 128MB. > >> I think this is unique requirement, at least I haven't seen other pieces >> of hardware have it. But it would be pretty trivial to add a setting to >> limit merges based on virtually contig, similarly to what is done for >> number of physical segments. > > I think there might be an FCoE device with that requirement too.
I've rebased nvmemq_review and added two patches from Jens that add support for requests with single range virtual addresses. Keith, will you take it for a spin and see if it fixes 068 for you? There might still be a problem with some flushes, I'm looking into this. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
