From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: George Spelvin <linux@horizon.com>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Update of file offset on write() etc. is non-atomic with I/O
Date: Mon, 3 Mar 2014 23:54:56 +0000 [thread overview]
Message-ID: <20140303235456.GR18016@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20140303233902.GP18016@ZenIV.linux.org.uk>
On Mon, Mar 03, 2014 at 11:39:02PM +0000, Al Viro wrote:
> On Mon, Mar 03, 2014 at 03:23:55PM -0800, Linus Torvalds wrote:
>
> > This just uses a "flags" field, and we currently only have two bits
> > that we use: FDPUT_FPUT and FDPUT_POS_UNLOCK. The first patch knows
> > that "fget_light()" writes 0/1 for that, which is the same as the
> > FDPUT_FPUT bit. I didn't bother to comment on it or clean it up, since
> > the second patch just removes that whole fget_light() mess.
> >
> > Comments?
>
> do_sendfile() is also there and this one is even more unpleasant ;-/
> We probably can ignore that one (until POSIX learns of its existence),
> thouhg...
OK, other than read/write/readv/writev/lseek we have only sendfile{,64} and
splice; everything else either deals with struct file that is guaranteed to
be not accessible by any syscall (e.g. coredump code) or is not a regular
file. So the only question is whether we care for syscalls that are
out of scope for POSIX.
next prev parent reply other threads:[~2014-03-03 23:54 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-03 21:03 Update of file offset on write() etc. is non-atomic with I/O George Spelvin
2014-03-03 21:26 ` Al Viro
2014-03-03 21:52 ` Linus Torvalds
2014-03-03 22:01 ` Al Viro
2014-03-03 22:17 ` Linus Torvalds
2014-03-03 23:28 ` Al Viro
2014-03-03 23:34 ` Linus Torvalds
2014-03-03 23:42 ` Al Viro
2014-03-03 23:59 ` Linus Torvalds
2014-03-04 0:23 ` Al Viro
2014-03-04 0:42 ` Linus Torvalds
2014-03-04 1:05 ` Al Viro
2014-03-04 20:00 ` Al Viro
2014-03-04 21:17 ` Linus Torvalds
2014-03-05 0:04 ` Al Viro
2014-03-10 15:55 ` Al Viro
2014-03-03 22:55 ` Linus Torvalds
2014-03-03 23:23 ` Linus Torvalds
2014-03-03 23:39 ` Al Viro
2014-03-03 23:54 ` Linus Torvalds
2014-03-03 23:54 ` Al Viro [this message]
2014-03-04 20:11 ` Cedric Blancher
2014-03-04 0:07 ` George Spelvin
2014-05-04 7:04 ` Michael Kerrisk
[not found] <a8df285f-de7f-4a3a-9a19-e0ad07ab3a5c@blur>
2014-02-20 18:15 ` Zuckerman, Boris
2014-02-20 18:29 ` Al Viro
2014-02-21 6:01 ` Michael Kerrisk (man-pages)
2014-02-23 1:18 ` Kevin Easton
2014-02-23 7:38 ` Michael Kerrisk (man-pages)
-- strict thread matches above, loose matches on Subject: below --
2014-02-17 15:41 Michael Kerrisk (man-pages)
2014-02-18 13:00 ` Michael Kerrisk
2014-02-20 17:14 ` Linus Torvalds
2014-03-03 17:36 ` Linus Torvalds
2014-03-03 21:45 ` Al Viro
2014-03-03 21:56 ` Linus Torvalds
2014-03-03 22:09 ` Al Viro
2014-03-03 22:20 ` Linus Torvalds
2014-03-03 22:01 ` Linus Torvalds
2014-03-03 22:10 ` Al Viro
2014-03-03 22:22 ` Linus Torvalds
2014-03-06 15:03 ` Michael Kerrisk (man-pages)
2014-03-07 3:38 ` Yongzhi Pan
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