Re: [PATCH v4 1/6] fs: introduce FMODE_ZONE_APPEND and IOCB_ZONE_APPEND

From: Christoph Hellwig
Date: Tue Jul 28 2020 - 03:27:04 EST


On Tue, Jul 28, 2020 at 02:49:59AM +0100, Matthew Wilcox wrote:
> On Sun, Jul 26, 2020 at 04:18:10PM +0100, Christoph Hellwig wrote:
> > Zone append is a protocol context that ha not business showing up
> > in a file system interface. The right interface is a generic way
> > to report the written offset for an append write for any kind of file.
> > So we should pick a better name like FMODE_REPORT_APPEND_OFFSET
> > (not that I particularly like that name, but it is the best I could
> > quickly come up with).
>
> Is it necessarily *append*? There were a spate of papers about ten
> years ago for APIs that were "write anywhere and I'll tell you where it
> ended up". So FMODE_ANONYMOUS_WRITE perhaps?

But that really is not the semantics I had in mind - both the semantics
for the proposed Linux file API and the NVMe Zone Append command say
write exactly at the write pointer (NVMe) or end of the file (file API).