Messages in this thread Patch in this message | | | Date | Fri, 13 Mar 2015 10:36:37 +0800 | From | Yijing Wang <> | Subject | Re: [PATCH v6 04/30] xen/PCI: Don't use deprecated function pci_scan_bus_parented() |
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>>>> + 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
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