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Date: Sat, 11 Mar 2017 13:44:10 -0800
From: Eric Biggers <ebiggers3@gmail.com>
To: linux-fsdevel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>,
        David Howells <dhowells@redhat.com>,
        linux-kernel@vger.kernel.org, Eric Biggers <ebiggers@google.com>
Subject: Re: [PATCH] statx: optimize copy of struct statx to userspace
Message-ID: <20170311214410.GA672@zzz>
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On Sat, Mar 11, 2017 at 02:15:10AM -0800, Eric Biggers wrote:
> stat() instead initializes its struct on the stack and copies it to
> userspace with a single call to copy_to_user().  This turns out to be
> much faster, and changing statx to do this makes it almost as fast as
> stat:

Hmm, I missed that the access_ok() check in sys_statx() will no longer be
needed.  I'm sending a revised patch that removes that too.

Eric