From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753405Ab0IOVJH (ORCPT ); Wed, 15 Sep 2010 17:09:07 -0400 Received: from g5t0006.atlanta.hp.com ([15.192.0.43]:1229 "EHLO g5t0006.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752789Ab0IOVJE (ORCPT ); Wed, 15 Sep 2010 17:09:04 -0400 Subject: [PATCH 1/3] x86/PCI: allocate space from the end of a region, not the beginning To: Jesse Barnes From: Bjorn Helgaas Cc: Brian Bloniarz , Charles Butterfield , Denys Vlasenko , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Becker , "H. Peter Anvin" , Yinghai Lu , Thomas Gleixner , Linus Torvalds , Ingo Molnar Date: Wed, 15 Sep 2010 15:09:02 -0600 Message-ID: <20100915210902.12365.19911.stgit@bob.kio> In-Reply-To: <20100915210818.12365.58732.stgit@bob.kio> References: <20100915210818.12365.58732.stgit@bob.kio> User-Agent: StGit/0.15 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Allocate from the end of a region, not the beginning. For example, if we need to allocate 0x800 bytes for a device on bus 0000:00 given these resources: [mem 0xbff00000-0xdfffffff] PCI Bus 0000:00 [mem 0xc0000000-0xdfffffff] PCI Bus 0000:02 the available space at [mem 0xbff00000-0xbfffffff] is passed to the alignment callback (pcibios_align_resource()). Prior to this patch, we would put the new 0x800 byte resource at the beginning of that available space, i.e., at [mem 0xbff00000-0xbff007ff]. With this patch, we put it at the end, at [mem 0xbffff800-0xbfffffff]. Reference: https://bugzilla.kernel.org/show_bug.cgi?id=16228#c41 Signed-off-by: Bjorn Helgaas --- arch/x86/pci/i386.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 5525309..1ff3e9f 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -65,7 +65,10 @@ pcibios_align_resource(void *data, const struct resource *res, resource_size_t size, resource_size_t align) { struct pci_dev *dev = data; - resource_size_t start = res->start; + resource_size_t start = ALIGN(res->end - size + 1, align); + + if (start < res->start) + start = res->start; if (res->flags & IORESOURCE_IO) { if (skip_isa_ioresource_align(dev))