On Wed, Jun 17, 2020 at 10:53:36PM +0530, Kanchan Joshi wrote: > This patchset enables issuing zone-append using aio and io-uring direct-io interface. > > For aio, this introduces opcode IOCB_CMD_ZONE_APPEND. Application uses start LBA > of the zone to issue append. On completion 'res2' field is used to return > zone-relative offset. > > For io-uring, this introduces three opcodes: IORING_OP_ZONE_APPEND/APPENDV/APPENDV_FIXED. > Since io_uring does not have aio-like res2, cqe->flags are repurposed to return zone-relative offset And what exactly are the semantics supposed to be? Remember the unix file abstractions does not know about zones at all. I really don't think squeezing low-level not quite block storage protocol details into the Linux read/write path is a good idea. What could be a useful addition is a way for O_APPEND/RWF_APPEND writes to report where they actually wrote, as that comes close to Zone Append while still making sense at our usual abstraction level for file I/O.
