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Date: Wed, 1 Jun 2016 16:44:40 +0200
Message-ID: <CANXojcw8pJDa66YS+0T-TjetmRwPgfdXWbNzi8rkUv6WKzUydQ@mail.gmail.com>
Subject: Re: [fuse-devel] Changes in 4.7.
From: Stef Bon <stefbon@gmail.com>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: "fuse-devel@lists.sourceforge.net" <fuse-devel@lists.sourceforge.net>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
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2016-06-01 15:52 GMT+02:00 Al Viro <viro@zeniv.linux.org.uk>:
> For regular files, the kernel serializes read()/write()/lseek() done on
> descriptors aliasing each other.  Now it does the same for getdents()/lseek()
> of directories.
>
> From the filesystem point of view, you might see two getdents() called
> in parallel only if their results should be unaffected by the order of
> operations.

Ah right! Now I understand. Thanks a lot for your explanation!
Of course when a second descriptor refers the same object, operations
like read/lseek have to be serialized.
If not strange things will happen.
I was thinking on a totally different level.

Stef