Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932108AbXAaBTq (ORCPT ); Tue, 30 Jan 2007 20:19:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932111AbXAaBTq (ORCPT ); Tue, 30 Jan 2007 20:19:46 -0500 Received: from mx1.redhat.com ([66.187.233.31]:44189 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932108AbXAaBTo (ORCPT ); Tue, 30 Jan 2007 20:19:44 -0500 Message-ID: <45BFEE85.30203@redhat.com> Date: Tue, 30 Jan 2007 20:19:01 -0500 From: Jeff Layton User-Agent: Thunderbird 1.5.0.9 (X11/20061219) MIME-Version: 1.0 To: Bodo Eggert <7eggert@gmx.de> CC: akpm@osdl.org, Jeff Layton , dev@sw.ru, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, torvalds@osdl.org Subject: Re: [PATCH] pipefs unique inode numbers References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1416 Lines: 35 Bodo Eggert wrote: > change pipefs to use a unique inode number equal to the memory > address unless it would be truncated. > > Signed-Off-By: Bodo Eggert <7eggert@gmx.de> > --- > Tested on i386. > > --- 2.6.19/fs/pipe.c.ori 2007-01-30 22:02:46.000000000 +0100 > +++ 2.6.19/fs/pipe.c 2007-01-30 23:22:27.000000000 +0100 > @@ -864,6 +864,10 @@ static struct inode * get_pipe_inode(voi > inode->i_uid = current->fsuid; > inode->i_gid = current->fsgid; > inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; > + /* The address of *inode is unique, so we'll get an unique inode number. > + * Off cause this will not work for 32 bit inodes on 64 bit systems. */ > + if (sizeof(inode->i_ino) >= sizeof(struct inode*)) > + inode->i_ino = (unsigned int) inode; > > return inode; > Also, that patch would break many 32-bit programs not compiled with large offsets when run in compatibility mode on a 64-bit kernel. If they were to do a stat on this inode, it would likely generate an EOVERFLOW error since the pointer address would probably not fit in a 32 bit field. That problem was the whole impetus for this set of patches. -- Jeff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/