On 2023/3/28 21:01, Ming Lei wrote: [...] >> >> >>> So re-using splice for this purpose is still bad not mention splice >>> can't support writeable spliced page. >>> >>> Wiring device io buffer with context registered buffer table looks like >>> another approach, however: >>> >>> 1) two uring command OPs for registering/unregistering this buffer in io fast >>> path has to be added since only userspace can know when buffer(reference) >>> isn't needed >> >> Yes, that's a good point. Registration replaces fuse master cmd, so it's >> one extra request for unregister, which might be fine. > > Unfortunately I don't think this way is good, the problem is that buffer > only has physical pages, and doesn't have userspace mapping, so why bother > to export it to userspace? > > As I replied to Ziyang, the current fused command can be extended to > this way easily, but I don't know why we need to use the buffer registration, > given userspace can't read/write the buffer, and fused command can cover > it just fine. > Hi Ming, I have replied to you in another email.
