On Tue, Mar 10, 2020 at 06:46:42PM +0900, Johannes Thumshirn wrote: > For null_blk the emulation is way simpler, as null_blk's zoned block > device emulation support already caches the write pointer position, so we > only need to report the position back to the upper layers. Additional > caching is not needed here. > > Testing has been conducted by translating RWF_APPEND DIOs into > REQ_OP_ZONE_APPEND commands in the block device's direct I/O function and > injecting errors by bypassing the block layer interface and directly > writing to the disc via the SCSI generic interface. We really need a user of this to be useful upstream. Didn't you plan to look into converting zonefs/iomap to use it? Without that it is at best a RFC. Even better would be converting zonefs and the f2fs zoned code so that can get rid of the old per-zone serialization in the I/O scheduler entirely.
