Linus Torvalds [off-list ref] 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 [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
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