From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yijing Wang Subject: Re: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() Date: Fri, 13 Mar 2015 10:36:37 +0800 Message-ID: <55024D35.6050509@huawei.com> References: <1425868467-9667-1-git-send-email-wangyijing@huawei.com> <1425868467-9667-5-git-send-email-wangyijing@huawei.com> <20150311223211.GB1082@google.com> <55017CA5.2010502@huawei.com> <20150312193505.GB7346@google.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150312193505.GB7346@google.com> Sender: linux-m68k-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Bjorn Helgaas Cc: Jiang Liu , linux-pci@vger.kernel.org, Yinghai Lu , linux-kernel@vger.kernel.org, Marc Zyngier , linux-arm-kernel@lists.infradead.org, Russell King , x86@kernel.org, Thomas Gleixner , Benjamin Herrenschmidt , Rusty Russell , Tony Luck , linux-ia64@vger.kernel.org, "David S. Miller" , Guan Xuetao , linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org, Liviu Dudau , Arnd Bergmann , Geert Uytterhoeven , Konrad Rzeszutek Wilk , xen-devel@lists.xenproject.org >>>> + pci_add_resource(&resources, &ioport_resource); >>>> + pci_add_resource(&resources, &iomem_resource); >>>> + pci_add_resource(&resources, &busn_resource); >>> >>> Since I don't want to export busn_resource, you might have to allocate your >>> own struct resource for it here. And, of course, figure out the details of >>> which PCI domain you're in and whether you need to share one struct >>> resource across several host bridges in the same domain. >> >> Allocate its own resource here is ok for me, as I mentioned in previous reply, >> so do we still need to add additional info to figure out which domain own the bus resource ? > > That's up to the caller. Only the platform knows which bridges it wants to > have in the same domain. In principle, every host bridge could be in its > own domain, since each bridge is the root of a unique PCI hierarchy. But > some platforms have firmware that assumes otherwise. I have no idea what > xen assumes. I'm not xen guy, so I don't know much about it, but because it call pci_scan_bus_parented() before, and in which busn_resource is always shared for different host bridges(same domain or not), I think add a static bus resource(0,255) should be safe, at least, it would not introduce new risk. Something like: diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..a69e529 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -446,9 +446,15 @@ static int pcifront_scan_root(struct pcifront_device *pdev, unsigned int domain, unsigned int bus) { struct pci_bus *b; + LIST_HEAD(resources); struct pcifront_sd *sd = NULL; struct pci_bus_entry *bus_entry = NULL; int err = 0; + static struct resource busn_res = { + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, + }; #ifndef CONFIG_PCI_DOMAINS if (domain != 0) { @@ -470,17 +476,21 @@ static int pcifront_scan_root(struct pcifront_device *pdev, err = -ENOMEM; goto err_out; } + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_res); pcifront_init_sd(sd, domain, bus, pdev); pci_lock_rescan_remove(); - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, - &pcifront_bus_ops, sd); + b = pci_scan_root_bus(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd, &resources); if (!b) { Bjorn, what do you think about ? Thanks! Yijing. > >>>> pcifront_init_sd(sd, domain, bus, pdev); >>>> >>>> pci_lock_rescan_remove(); >>>> >>>> - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, >>>> - &pcifront_bus_ops, sd); >>>> + b = pci_scan_root_bus(&pdev->xdev->dev, bus, >>>> + &pcifront_bus_ops, sd, &resources); >>>> if (!b) { >>>> dev_err(&pdev->xdev->dev, >>>> "Error creating PCI Frontend Bus!\n"); >>>> err = -ENOMEM; >>>> pci_unlock_rescan_remove(); >>>> + pci_free_resource_list(&resources); >>>> goto err_out; >>>> } >>>> >>>> @@ -488,7 +494,7 @@ static int pcifront_scan_root(struct pcifront_device *pdev, >>>> >>>> list_add(&bus_entry->list, &pdev->root_buses); >>>> >>>> - /* pci_scan_bus_parented skips devices which do not have a have >>>> + /* pci_scan_root_bus skips devices which do not have a >>>> * devfn==0. The pcifront_scan_bus enumerates all devfn. */ >>>> err = pcifront_scan_bus(pdev, domain, bus, b); >>>> >>>> -- >>>> 1.7.1 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> . >>> >> >> >> -- >> Thanks! >> Yijing >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- Thanks! Yijing From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yijing Wang Date: Fri, 13 Mar 2015 02:36:37 +0000 Subject: Re: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() Message-Id: <55024D35.6050509@huawei.com> List-Id: References: <1425868467-9667-1-git-send-email-wangyijing@huawei.com> <1425868467-9667-5-git-send-email-wangyijing@huawei.com> <20150311223211.GB1082@google.com> <55017CA5.2010502@huawei.com> <20150312193505.GB7346@google.com> In-Reply-To: <20150312193505.GB7346@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Bjorn Helgaas Cc: Jiang Liu , linux-pci@vger.kernel.org, Yinghai Lu , linux-kernel@vger.kernel.org, Marc Zyngier , linux-arm-kernel@lists.infradead.org, Russell King , x86@kernel.org, Thomas Gleixner , Benjamin Herrenschmidt , Rusty Russell , Tony Luck , linux-ia64@vger.kernel.org, "David S. Miller" , Guan Xuetao , linux-alpha@vger.kernel.org, linux-m68k@vger.kernel.org, Liviu Dudau , Arnd Bergmann , Geert Uytterhoeven , Konrad Rzeszutek Wilk , xen-devel@lists.xenproject.org >>>> + pci_add_resource(&resources, &ioport_resource); >>>> + pci_add_resource(&resources, &iomem_resource); >>>> + pci_add_resource(&resources, &busn_resource); >>> >>> Since I don't want to export busn_resource, you might have to allocate your >>> own struct resource for it here. And, of course, figure out the details of >>> which PCI domain you're in and whether you need to share one struct >>> resource across several host bridges in the same domain. >> >> Allocate its own resource here is ok for me, as I mentioned in previous reply, >> so do we still need to add additional info to figure out which domain own the bus resource ? > > That's up to the caller. Only the platform knows which bridges it wants to > have in the same domain. In principle, every host bridge could be in its > own domain, since each bridge is the root of a unique PCI hierarchy. But > some platforms have firmware that assumes otherwise. I have no idea what > xen assumes. I'm not xen guy, so I don't know much about it, but because it call pci_scan_bus_parented() before, and in which busn_resource is always shared for different host bridges(same domain or not), I think add a static bus resource(0,255) should be safe, at least, it would not introduce new risk. Something like: diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..a69e529 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -446,9 +446,15 @@ static int pcifront_scan_root(struct pcifront_device *pdev, unsigned int domain, unsigned int bus) { struct pci_bus *b; + LIST_HEAD(resources); struct pcifront_sd *sd = NULL; struct pci_bus_entry *bus_entry = NULL; int err = 0; + static struct resource busn_res = { + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, + }; #ifndef CONFIG_PCI_DOMAINS if (domain != 0) { @@ -470,17 +476,21 @@ static int pcifront_scan_root(struct pcifront_device *pdev, err = -ENOMEM; goto err_out; } + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_res); pcifront_init_sd(sd, domain, bus, pdev); pci_lock_rescan_remove(); - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, - &pcifront_bus_ops, sd); + b = pci_scan_root_bus(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd, &resources); if (!b) { Bjorn, what do you think about ? Thanks! Yijing. > >>>> pcifront_init_sd(sd, domain, bus, pdev); >>>> >>>> pci_lock_rescan_remove(); >>>> >>>> - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, >>>> - &pcifront_bus_ops, sd); >>>> + b = pci_scan_root_bus(&pdev->xdev->dev, bus, >>>> + &pcifront_bus_ops, sd, &resources); >>>> if (!b) { >>>> dev_err(&pdev->xdev->dev, >>>> "Error creating PCI Frontend Bus!\n"); >>>> err = -ENOMEM; >>>> pci_unlock_rescan_remove(); >>>> + pci_free_resource_list(&resources); >>>> goto err_out; >>>> } >>>> >>>> @@ -488,7 +494,7 @@ static int pcifront_scan_root(struct pcifront_device *pdev, >>>> >>>> list_add(&bus_entry->list, &pdev->root_buses); >>>> >>>> - /* pci_scan_bus_parented skips devices which do not have a have >>>> + /* pci_scan_root_bus skips devices which do not have a >>>> * devfn=0. The pcifront_scan_bus enumerates all devfn. */ >>>> err = pcifront_scan_bus(pdev, domain, bus, b); >>>> >>>> -- >>>> 1.7.1 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> . >>> >> >> >> -- >> Thanks! >> Yijing >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- Thanks! Yijing From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga03-in.huawei.com ([119.145.14.66]:60731 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752632AbbCMChH (ORCPT ); Thu, 12 Mar 2015 22:37:07 -0400 Message-ID: <55024D35.6050509@huawei.com> Date: Fri, 13 Mar 2015 10:36:37 +0800 From: Yijing Wang MIME-Version: 1.0 To: Bjorn Helgaas CC: Jiang Liu , , Yinghai Lu , , Marc Zyngier , , Russell King , , Thomas Gleixner , Benjamin Herrenschmidt , Rusty Russell , Tony Luck , , "David S. Miller" , "Guan Xuetao" , , , Liviu Dudau , "Arnd Bergmann" , Geert Uytterhoeven , "Konrad Rzeszutek Wilk" , Subject: Re: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() References: <1425868467-9667-1-git-send-email-wangyijing@huawei.com> <1425868467-9667-5-git-send-email-wangyijing@huawei.com> <20150311223211.GB1082@google.com> <55017CA5.2010502@huawei.com> <20150312193505.GB7346@google.com> In-Reply-To: <20150312193505.GB7346@google.com> Content-Type: text/plain; charset="ISO-8859-1" Sender: linux-pci-owner@vger.kernel.org List-ID: >>>> + pci_add_resource(&resources, &ioport_resource); >>>> + pci_add_resource(&resources, &iomem_resource); >>>> + pci_add_resource(&resources, &busn_resource); >>> >>> Since I don't want to export busn_resource, you might have to allocate your >>> own struct resource for it here. And, of course, figure out the details of >>> which PCI domain you're in and whether you need to share one struct >>> resource across several host bridges in the same domain. >> >> Allocate its own resource here is ok for me, as I mentioned in previous reply, >> so do we still need to add additional info to figure out which domain own the bus resource ? > > That's up to the caller. Only the platform knows which bridges it wants to > have in the same domain. In principle, every host bridge could be in its > own domain, since each bridge is the root of a unique PCI hierarchy. But > some platforms have firmware that assumes otherwise. I have no idea what > xen assumes. I'm not xen guy, so I don't know much about it, but because it call pci_scan_bus_parented() before, and in which busn_resource is always shared for different host bridges(same domain or not), I think add a static bus resource(0,255) should be safe, at least, it would not introduce new risk. Something like: diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..a69e529 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -446,9 +446,15 @@ static int pcifront_scan_root(struct pcifront_device *pdev, unsigned int domain, unsigned int bus) { struct pci_bus *b; + LIST_HEAD(resources); struct pcifront_sd *sd = NULL; struct pci_bus_entry *bus_entry = NULL; int err = 0; + static struct resource busn_res = { + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, + }; #ifndef CONFIG_PCI_DOMAINS if (domain != 0) { @@ -470,17 +476,21 @@ static int pcifront_scan_root(struct pcifront_device *pdev, err = -ENOMEM; goto err_out; } + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_res); pcifront_init_sd(sd, domain, bus, pdev); pci_lock_rescan_remove(); - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, - &pcifront_bus_ops, sd); + b = pci_scan_root_bus(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd, &resources); if (!b) { Bjorn, what do you think about ? Thanks! Yijing. > >>>> pcifront_init_sd(sd, domain, bus, pdev); >>>> >>>> pci_lock_rescan_remove(); >>>> >>>> - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, >>>> - &pcifront_bus_ops, sd); >>>> + b = pci_scan_root_bus(&pdev->xdev->dev, bus, >>>> + &pcifront_bus_ops, sd, &resources); >>>> if (!b) { >>>> dev_err(&pdev->xdev->dev, >>>> "Error creating PCI Frontend Bus!\n"); >>>> err = -ENOMEM; >>>> pci_unlock_rescan_remove(); >>>> + pci_free_resource_list(&resources); >>>> goto err_out; >>>> } >>>> >>>> @@ -488,7 +494,7 @@ static int pcifront_scan_root(struct pcifront_device *pdev, >>>> >>>> list_add(&bus_entry->list, &pdev->root_buses); >>>> >>>> - /* pci_scan_bus_parented skips devices which do not have a have >>>> + /* pci_scan_root_bus skips devices which do not have a >>>> * devfn==0. The pcifront_scan_bus enumerates all devfn. */ >>>> err = pcifront_scan_bus(pdev, domain, bus, b); >>>> >>>> -- >>>> 1.7.1 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> . >>> >> >> >> -- >> Thanks! >> Yijing >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- Thanks! Yijing From mboxrd@z Thu Jan 1 00:00:00 1970 From: wangyijing@huawei.com (Yijing Wang) Date: Fri, 13 Mar 2015 10:36:37 +0800 Subject: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() In-Reply-To: <20150312193505.GB7346@google.com> References: <1425868467-9667-1-git-send-email-wangyijing@huawei.com> <1425868467-9667-5-git-send-email-wangyijing@huawei.com> <20150311223211.GB1082@google.com> <55017CA5.2010502@huawei.com> <20150312193505.GB7346@google.com> Message-ID: <55024D35.6050509@huawei.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org >>>> + pci_add_resource(&resources, &ioport_resource); >>>> + pci_add_resource(&resources, &iomem_resource); >>>> + pci_add_resource(&resources, &busn_resource); >>> >>> Since I don't want to export busn_resource, you might have to allocate your >>> own struct resource for it here. And, of course, figure out the details of >>> which PCI domain you're in and whether you need to share one struct >>> resource across several host bridges in the same domain. >> >> Allocate its own resource here is ok for me, as I mentioned in previous reply, >> so do we still need to add additional info to figure out which domain own the bus resource ? > > That's up to the caller. Only the platform knows which bridges it wants to > have in the same domain. In principle, every host bridge could be in its > own domain, since each bridge is the root of a unique PCI hierarchy. But > some platforms have firmware that assumes otherwise. I have no idea what > xen assumes. I'm not xen guy, so I don't know much about it, but because it call pci_scan_bus_parented() before, and in which busn_resource is always shared for different host bridges(same domain or not), I think add a static bus resource(0,255) should be safe, at least, it would not introduce new risk. Something like: diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..a69e529 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -446,9 +446,15 @@ static int pcifront_scan_root(struct pcifront_device *pdev, unsigned int domain, unsigned int bus) { struct pci_bus *b; + LIST_HEAD(resources); struct pcifront_sd *sd = NULL; struct pci_bus_entry *bus_entry = NULL; int err = 0; + static struct resource busn_res = { + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, + }; #ifndef CONFIG_PCI_DOMAINS if (domain != 0) { @@ -470,17 +476,21 @@ static int pcifront_scan_root(struct pcifront_device *pdev, err = -ENOMEM; goto err_out; } + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_res); pcifront_init_sd(sd, domain, bus, pdev); pci_lock_rescan_remove(); - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, - &pcifront_bus_ops, sd); + b = pci_scan_root_bus(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd, &resources); if (!b) { Bjorn, what do you think about ? Thanks! Yijing. > >>>> pcifront_init_sd(sd, domain, bus, pdev); >>>> >>>> pci_lock_rescan_remove(); >>>> >>>> - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, >>>> - &pcifront_bus_ops, sd); >>>> + b = pci_scan_root_bus(&pdev->xdev->dev, bus, >>>> + &pcifront_bus_ops, sd, &resources); >>>> if (!b) { >>>> dev_err(&pdev->xdev->dev, >>>> "Error creating PCI Frontend Bus!\n"); >>>> err = -ENOMEM; >>>> pci_unlock_rescan_remove(); >>>> + pci_free_resource_list(&resources); >>>> goto err_out; >>>> } >>>> >>>> @@ -488,7 +494,7 @@ static int pcifront_scan_root(struct pcifront_device *pdev, >>>> >>>> list_add(&bus_entry->list, &pdev->root_buses); >>>> >>>> - /* pci_scan_bus_parented skips devices which do not have a have >>>> + /* pci_scan_root_bus skips devices which do not have a >>>> * devfn==0. The pcifront_scan_bus enumerates all devfn. */ >>>> err = pcifront_scan_bus(pdev, domain, bus, b); >>>> >>>> -- >>>> 1.7.1 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >>>> the body of a message to majordomo at vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> . >>> >> >> >> -- >> Thanks! >> Yijing >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- Thanks! Yijing From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752288AbbCMChP (ORCPT ); Thu, 12 Mar 2015 22:37:15 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:60731 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752632AbbCMChH (ORCPT ); Thu, 12 Mar 2015 22:37:07 -0400 Message-ID: <55024D35.6050509@huawei.com> Date: Fri, 13 Mar 2015 10:36:37 +0800 From: Yijing Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Bjorn Helgaas CC: Jiang Liu , , Yinghai Lu , , Marc Zyngier , , Russell King , , Thomas Gleixner , Benjamin Herrenschmidt , Rusty Russell , Tony Luck , , "David S. Miller" , "Guan Xuetao" , , , Liviu Dudau , "Arnd Bergmann" , Geert Uytterhoeven , "Konrad Rzeszutek Wilk" , Subject: Re: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() References: <1425868467-9667-1-git-send-email-wangyijing@huawei.com> <1425868467-9667-5-git-send-email-wangyijing@huawei.com> <20150311223211.GB1082@google.com> <55017CA5.2010502@huawei.com> <20150312193505.GB7346@google.com> In-Reply-To: <20150312193505.GB7346@google.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.27.212] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A0C0201.55024D41.00D4,ss=1,re=0.001,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-05-26 15:14:31, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 119937550651d4b75910862498a885d7 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>>> + pci_add_resource(&resources, &ioport_resource); >>>> + pci_add_resource(&resources, &iomem_resource); >>>> + pci_add_resource(&resources, &busn_resource); >>> >>> Since I don't want to export busn_resource, you might have to allocate your >>> own struct resource for it here. And, of course, figure out the details of >>> which PCI domain you're in and whether you need to share one struct >>> resource across several host bridges in the same domain. >> >> Allocate its own resource here is ok for me, as I mentioned in previous reply, >> so do we still need to add additional info to figure out which domain own the bus resource ? > > That's up to the caller. Only the platform knows which bridges it wants to > have in the same domain. In principle, every host bridge could be in its > own domain, since each bridge is the root of a unique PCI hierarchy. But > some platforms have firmware that assumes otherwise. I have no idea what > xen assumes. I'm not xen guy, so I don't know much about it, but because it call pci_scan_bus_parented() before, and in which busn_resource is always shared for different host bridges(same domain or not), I think add a static bus resource(0,255) should be safe, at least, it would not introduce new risk. Something like: diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c index b1ffebe..a69e529 100644 --- a/drivers/pci/xen-pcifront.c +++ b/drivers/pci/xen-pcifront.c @@ -446,9 +446,15 @@ static int pcifront_scan_root(struct pcifront_device *pdev, unsigned int domain, unsigned int bus) { struct pci_bus *b; + LIST_HEAD(resources); struct pcifront_sd *sd = NULL; struct pci_bus_entry *bus_entry = NULL; int err = 0; + static struct resource busn_res = { + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, + }; #ifndef CONFIG_PCI_DOMAINS if (domain != 0) { @@ -470,17 +476,21 @@ static int pcifront_scan_root(struct pcifront_device *pdev, err = -ENOMEM; goto err_out; } + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_res); pcifront_init_sd(sd, domain, bus, pdev); pci_lock_rescan_remove(); - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, - &pcifront_bus_ops, sd); + b = pci_scan_root_bus(&pdev->xdev->dev, bus, + &pcifront_bus_ops, sd, &resources); if (!b) { Bjorn, what do you think about ? Thanks! Yijing. > >>>> pcifront_init_sd(sd, domain, bus, pdev); >>>> >>>> pci_lock_rescan_remove(); >>>> >>>> - b = pci_scan_bus_parented(&pdev->xdev->dev, bus, >>>> - &pcifront_bus_ops, sd); >>>> + b = pci_scan_root_bus(&pdev->xdev->dev, bus, >>>> + &pcifront_bus_ops, sd, &resources); >>>> if (!b) { >>>> dev_err(&pdev->xdev->dev, >>>> "Error creating PCI Frontend Bus!\n"); >>>> err = -ENOMEM; >>>> pci_unlock_rescan_remove(); >>>> + pci_free_resource_list(&resources); >>>> goto err_out; >>>> } >>>> >>>> @@ -488,7 +494,7 @@ static int pcifront_scan_root(struct pcifront_device *pdev, >>>> >>>> list_add(&bus_entry->list, &pdev->root_buses); >>>> >>>> - /* pci_scan_bus_parented skips devices which do not have a have >>>> + /* pci_scan_root_bus skips devices which do not have a >>>> * devfn==0. The pcifront_scan_bus enumerates all devfn. */ >>>> err = pcifront_scan_bus(pdev, domain, bus, b); >>>> >>>> -- >>>> 1.7.1 >>>> >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >>>> the body of a message to majordomo@vger.kernel.org >>>> More majordomo info at http://vger.kernel.org/majordomo-info.html >>> >>> . >>> >> >> >> -- >> Thanks! >> Yijing >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-pci" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > -- Thanks! Yijing