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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 6 Apr 2020 08:53:48 -0700
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Subject: Re: [GIT PULL] 9p update for 5.7
To:     Dominique Martinet <asmadeus@codewreck.org>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        v9fs-developer@lists.sourceforge.net
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On Mon, Apr 6, 2020 at 4:07 AM Dominique Martinet
<asmadeus@codewreck.org> wrote:
>
> - Fix read with O_NONBLOCK to allow incomplete read and return
> immediately

Hmm. This is kind of special semantics (normally a POSIX filesystem
ignores O_NONBLOCK), but I guess it makes sense for a network
filesystem.

It might be worth a bti more documentation/commenting because of the
special semantics. For example, since you don't have 'poll()',
O_NONBLOCK doesn't really mean "nonblocking", it means "stop earlier"
if I read that patch right. You can't just return -EAGAIN because
there's no way to then avoid busy looping..

                Linus