Messages in this thread | | | From | Yongji Xie <> | Date | Tue, 29 Jun 2021 14:40:59 +0800 | Subject | Re: Re: [PATCH v8 00/10] Introduce VDUSE - vDPA Device in Userspace |
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On Tue, Jun 29, 2021 at 12:13 PM Jason Wang <jasowang@redhat.com> wrote: > > > 在 2021/6/28 下午6:32, Yongji Xie 写道: > >> The large barrier is bounce-buffer mapping: SPDK requires hugepages > >> for NVMe over PCIe and RDMA, so take some preallcoated hugepages to > >> map as bounce buffer is necessary. Or it's hard to avoid an extra > >> memcpy from bounce-buffer to hugepage. > >> If you can add an option to map hugepages as bounce-buffer, > >> then SPDK could also be a potential user of vduse. > >> > > I think we can support registering user space memory for bounce-buffer > > use like XDP does. But this needs to pin the pages, so I didn't > > consider it in this initial version. > > > > Note that userspace should be unaware of the existence of the bounce buffer. >
If so, it might be hard to use umem. Because we can't use umem for coherent mapping which needs physical address contiguous space.
Thanks, Yongji
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