Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756481Ab0DNRUo (ORCPT ); Wed, 14 Apr 2010 13:20:44 -0400 Received: from rcsinet11.oracle.com ([148.87.113.123]:27280 "EHLO rcsinet11.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755485Ab0DNRUn (ORCPT ); Wed, 14 Apr 2010 13:20:43 -0400 Message-ID: <4BC5F98D.5070601@oracle.com> Date: Wed, 14 Apr 2010 10:21:17 -0700 From: Yinghai Lu User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100228 SUSE/3.0.3-1.1.1 Thunderbird/3.0.3 MIME-Version: 1.0 To: Bjorn Helgaas CC: "H. Peter Anvin" , Andy Isaacson , guenter.roeck@ericsson.com, Linus Torvalds , Thomas Gleixner , Ingo Molnar , "linux-pci@vger.kernel.org" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , Thomas Renninger Subject: Re: [PATCH -v2 1/2] x86: Reserve [0xa0000, 0x100000] in e820 map References: <20100409223532.GC11130@hexapodia.org> <4BC4E8FB.8060802@zytor.com> <4BC51312.6080302@oracle.com> <201004141055.50172.bjorn.helgaas@hp.com> In-Reply-To: <201004141055.50172.bjorn.helgaas@hp.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsmt354.oracle.com [141.146.40.154] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090206.4BC5F945.0157:SCFMA4539814,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5153 Lines: 124 On 04/14/2010 09:55 AM, Bjorn Helgaas wrote: > On Tuesday 13 April 2010 06:57:54 pm Yinghai wrote: > > >> Subject: [PATCH] x86, resource: Add reserve_region_with_split_check_child() >> >> It will cover the whole region to BUSY, except that some regions that have >> children under them. >> >> those children normally is PCI bar but it is falling into E820_RESERVED. >> We can not put BUSY on them, otherwise driver can not use pci_request_region() >> later >> >> /proc/iomem will have >> 00010000-00094fff : System RAM >> 00095000-0009ffff : reserved >> 000a0000-000bffff : PCI Bus 0000:00 >> 000a0000-000bffff : reserved >> 000c0000-000cffff : reserved >> 000d0000-000dffff : PCI Bus 0000:00 >> 000d0000-000dffff : reserved >> 000e0000-000fffff : reserved >> >> Signed-off-by: Yinghai Lu >> >> --- >> arch/x86/kernel/e820.c | 10 +++++++--- >> include/linux/ioport.h | 3 +++ >> kernel/resource.c | 24 +++++++++++++++++++----- >> 3 files changed, 29 insertions(+), 8 deletions(-) >> >> Index: linux-2.6/arch/x86/kernel/e820.c >> =================================================================== >> --- linux-2.6.orig/arch/x86/kernel/e820.c >> +++ linux-2.6/arch/x86/kernel/e820.c >> @@ -1094,7 +1094,7 @@ void __init e820_reserve_resources(void) >> * pci device BAR resource and insert them later in >> * pcibios_resource_survey() >> */ >> - if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) { >> + if (e820.map[i].type != E820_RESERVED) { >> res->flags |= IORESOURCE_BUSY; >> insert_resource(&iomem_resource, res); >> } >> @@ -1135,8 +1135,12 @@ void __init e820_reserve_resources_late( >> >> res = e820_res; >> for (i = 0; i < e820.nr_map; i++) { >> - if (!res->parent && res->end) >> - insert_resource_expand_to_fit(&iomem_resource, res); >> + if (!res->parent && res->end) { >> + if (res->start < (1ULL<<20)) { >> + reserve_region_with_split_check_child(&iomem_resource, res->start, res->end, res->name); >> + } else >> + insert_resource_expand_to_fit(&iomem_resource, res); >> > I don't like adding all these special-purpose resource interfaces, e.g., > insert_resource_expand_to_fit(), reserve_region_with_split(), > reserve_region_with_split_check_child(), etc. They tend to be only > used by one caller, which is a clue to me that we're doing something > wrong. > > Sometimes we'd like to print debug information in them (as we do in > insert_resource_expand_to_fit()), but we don't have enough context, > so the message isn't very meaningful. > print out related resource tree segment ? > I think it's better to have more generic interfaces that allow us to > implement this sort of functionality where it's used and where we > have the context to print useful messages. For example, could the > reserve_region_with_split_check_child() functionality be implemented > in e820.c by building on something like request_resource_conflict()? > > >> + } >> res++; >> } >> >> Index: linux-2.6/include/linux/ioport.h >> =================================================================== >> --- linux-2.6.orig/include/linux/ioport.h >> +++ linux-2.6/include/linux/ioport.h >> @@ -120,6 +120,9 @@ void release_child_resources(struct reso >> extern void reserve_region_with_split(struct resource *root, >> resource_size_t start, resource_size_t end, >> const char *name); >> +void reserve_region_with_split_check_child(struct resource *root, >> + resource_size_t start, resource_size_t end, >> + const char *name); >> extern struct resource *insert_resource_conflict(struct resource *parent, struct resource *new); >> extern int insert_resource(struct resource *parent, struct resource *new); >> extern void insert_resource_expand_to_fit(struct resource *root, struct resource *new); >> Index: linux-2.6/kernel/resource.c >> =================================================================== >> --- linux-2.6.orig/kernel/resource.c >> +++ linux-2.6/kernel/resource.c >> @@ -609,7 +609,7 @@ int adjust_resource(struct resource *res >> >> static void __init __reserve_region_with_split(struct resource *root, >> resource_size_t start, resource_size_t end, >> - const char *name) >> + const char *name, bool check_child) >> { >> struct resource *parent = root; >> struct resource *conflict; >> @@ -631,13 +631,18 @@ static void __init __reserve_region_with >> kfree(res); >> >> /* conflict covered whole area */ >> - if (conflict->start <= start && conflict->end >= end) >> + if (conflict->start <= start && conflict->end >= end) { >> + if (check_child && !conflict->child && strstr(conflict->name, "PCI Bus")) >> > This is kind of gross, too. Checking the name of a resource for "PCI Bus"? > yes, in case some system have device on BUS 0 directly. but have device have pci BAR below 1M and fall into E820_RESERVED. YH -- 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/