Re: [Nbd] [PATCH] add support for NBD_CMD_TRIM, update docs

[Wouter Verhelst <w@...112...>]

On Thu, Sep 08, 2011 at 05:17:45PM +0100, Alex Bligh wrote:
> Paolo,
> 
> Thanks for this. Do you have as server implementation of TRIM? I might
> have a go if not.
> 
> One comment below:
> 
> > @@ -77,8 +80,7 @@ description of the data that is sent.
> >  S: "NBDMAGIC" (the INIT_PASSWD in the code)
> >  S: 0x00420281861253 (cliserv_magic, a magic number)
> >  S: size of the export in bytes, 64 bit unsigned int
> > -S: flags, 4 bytes (may have the NBD_FLAG_READ_ONLY flag set if the
> > -   export is read-only; the rest is reserved)
> > +S: flags, 4 bytes
> >  S: 124 bytes of zeroes (registered for future use, yes this is
> >     excessive).
> >
> > @@ -140,8 +142,7 @@ Once all options are set, the server replies with
> > information about the  used export:
> >
> >  S: size of the export in bytes, 64 bit unsigned int
> > -S: flags (16 bits unsigned int, may contain NBD_FLAG_READ_ONLY if the
> > -   export is read-only)
> > +S: flags (16 bits unsigned int)
> >  S: 124 bytes of zeroes (forgot to remove that, oops)
> 
> I'm confused about these change. Mind you I'm confused about most of the
> READ_ONLY stuff as the original implementation did not appear to work :-)

Basically, it removes the confusing mention of READ_ONLY stuff in the
flags field in proto.txt, and replaces it with a more detailed and
correct description of all the possible flags. It's perfectly okay :-)

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