From: David Chinner Subject: Re: [PATCH 1/5] fallocate() implementation in i86, x86_64 and powerpc Date: Fri, 4 May 2007 16:07:31 +1000 Message-ID: <20070504060731.GJ32602149@melbourne.sgi.com> References: <20070329101010.7a2b8783.akpm@linux-foundation.org> <20070330071417.GI355@devserv.devel.redhat.com> <20070417125514.GA7574@amitarora.in.ibm.com> <20070418130600.GW5967@schatzie.adilger.int> <20070420135146.GA21352@amitarora.in.ibm.com> <20070420145918.GY355@devserv.devel.redhat.com> <20070424121632.GA10136@amitarora.in.ibm.com> <20070426175056.GA25321@amitarora.in.ibm.com> <20070426180332.GA7209@amitarora.in.ibm.com> <20070503212955.b1b6443c.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Amit K. Arora" , torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, xfs@oss.sgi.com, suparna@in.ibm.com, cmm@us.ibm.com To: Andrew Morton Return-path: Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:53879 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932231AbXEDGIG (ORCPT ); Fri, 4 May 2007 02:08:06 -0400 Content-Disposition: inline In-Reply-To: <20070503212955.b1b6443c.akpm@linux-foundation.org> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Thu, May 03, 2007 at 09:29:55PM -0700, Andrew Morton wrote: > On Thu, 26 Apr 2007 23:33:32 +0530 "Amit K. Arora" wrote: > > > This patch implements the fallocate() system call and adds support for > > i386, x86_64 and powerpc. > > > > ... > > +{ > > + struct file *file; > > + struct inode *inode; > > + long ret = -EINVAL; > > + > > + if (len == 0 || offset < 0) > > + goto out; > > The posix spec implies that negative `len' is permitted - presumably "allocate > ahead of `offset'". How peculiar. I just checked the man page for posix_fallocate() and it says: EINVAL offset or len was less than zero. We should probably follow this lead. > > + > > + ret = -ENODEV; > > + if (!S_ISREG(inode->i_mode)) > > + goto out_fput; > > So we return ENODEV against an S_ISBLK fd, as per the posix spec. That > seems a bit silly of them. Hmmmm - I thought that the intention of sys_fallocate() was to be generic enough to eventually allow preallocation on directories. If that is the case, then this check will prevent that.... Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group