Re: [PATCH 0/3] vmsplice: make vmsplice a trivial wrapper for preadv2/pwritev2

[Herbert Xu]

Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> Nope. If your web server opens files with write access, I'd be
> extremely surprised.
> 
> And if you don't have write access, and you're sending out data from
> files you opened just for reading - the onle sane case - you hit all
> the existing problems with "I can certainly look up pages, but I damn
> well shouldn't pass those pages to the networking code without copying
> them".

How about using write access as the gate to zero copy?

IOW allow zero-copy if you already hold write access, otherwise
perform a copy.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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