[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v6 2/2] PCI: acpiphp: remove all functions in sl
From: |
Yinghai Lu |
Subject: |
Re: [Qemu-devel] [PATCH v6 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx |
Date: |
Tue, 22 May 2012 22:04:12 -0700 |
On Tue, May 22, 2012 at 9:35 PM, Bjorn Helgaas <address@hidden> wrote:
> From: Amos Kong <address@hidden>
>
> When we add a device with acpiphp, we enumerate all functions in the
> slot with pci_scan_slot(), regardless of whether they have associated
> ACPI methods such as _EJ0.
>
> When removing the device, we previously removed only the functions
> with those ACPI methods. This patch makes the remove symmetric with the
> add: we remove all functions in the slot, whether they have associated
> ACPI methods or not.
>
> With qemu-kvm and SeaBIOS, we can build a multi-function device where
> only function 0 has _EJ0 and _ADR (see bugzilla below). Removing and
> re-adding that device works correctly with Windows guests. This patch
> makes it also work in Linux guests.
>
> [bhelgaas: restructure loop iteration, pull out of slot->funcs loop]
> Reference: https://bugzilla.kernel.org/show_bug.cgi?id=43219
> Signed-off-by: Amos Kong <address@hidden>
> Signed-off-by: Bjorn Helgaas <address@hidden>
> ---
> drivers/pci/hotplug/acpiphp_glue.c | 39
> +++++++++++++++++++++++++++---------
> 1 files changed, 29 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/pci/hotplug/acpiphp_glue.c
> b/drivers/pci/hotplug/acpiphp_glue.c
> index c8f9991..9aff4f0 100644
> --- a/drivers/pci/hotplug/acpiphp_glue.c
> +++ b/drivers/pci/hotplug/acpiphp_glue.c
> @@ -878,6 +878,21 @@ static void disable_bridges(struct pci_bus *bus)
> }
> }
>
> +/* return first device in slot, acquiring a reference on it */
> +static struct pci_dev *dev_in_slot(struct acpiphp_slot *slot)
> +{
> + struct pci_bus *bus = slot->bridge->pci_bus;
> + struct pci_dev *dev;
> +
> + down_read(&pci_bus_sem);
> + list_for_each_entry(dev, &bus->devices, bus_list)
> + if (PCI_SLOT(dev->devfn) == slot->device)
> + return pci_dev_get(dev);
> + up_read(&pci_bus_sem);
Do you need to keep that pci_bus_sem operation pair on return path?
> +
> + return NULL;
> +}
> +
> /**
> * disable_device - disable a slot
> * @slot: ACPI PHP slot
> @@ -902,18 +917,22 @@ static int disable_device(struct acpiphp_slot *slot)
> (u32)1, NULL, NULL);
> func->bridge = NULL;
> }
> + }
>
> - pdev = pci_get_slot(slot->bridge->pci_bus,
> - PCI_DEVFN(slot->device, func->function));
> - if (pdev) {
> - pci_stop_bus_device(pdev);
> - if (pdev->subordinate) {
> - disable_bridges(pdev->subordinate);
> - pci_disable_device(pdev);
> - }
> - __pci_remove_bus_device(pdev);
> - pci_dev_put(pdev);
> + /*
> + * enable_device() enumerates all functions in this device via
> + * pci_scan_slot(), whether they have associated ACPI hotplug
> + * methods (_EJ0, etc.) or not. Therefore, we remove all functions
> + * here.
> + */
> + while ((pdev = dev_in_slot(slot))) {
> + pci_stop_bus_device(pdev);
> + if (pdev->subordinate) {
> + disable_bridges(pdev->subordinate);
> + pci_disable_device(pdev);
> }
> + __pci_remove_bus_device(pdev);
> + pci_dev_put(pdev);
> }
>
> list_for_each_entry(func, &slot->funcs, sibling) {
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> the body of a message to address@hidden
> More majordomo info at http://vger.kernel.org/majordomo-info.html
- [Qemu-devel] [PATCH v6 0/2] PCI: acpiphp: remove multifunction devices, Bjorn Helgaas, 2012/05/23
- [Qemu-devel] [PATCH v6 1/2] PCI: acpiphp: fix function 0 leak when disabling a slot, Bjorn Helgaas, 2012/05/23
- [Qemu-devel] [PATCH v6 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx, Bjorn Helgaas, 2012/05/23
- Re: [Qemu-devel] [PATCH v6 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx,
Yinghai Lu <=
- [Qemu-devel] [PATCH v7 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx, Amos Kong, 2012/05/23
- Re: [Qemu-devel] [PATCH v7 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx, Yinghai Lu, 2012/05/23
- [Qemu-devel] [PATCH v8 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx, Amos Kong, 2012/05/23
- Re: [Qemu-devel] [PATCH v8 2/2] PCI: acpiphp: remove all functions in slot, even without ACPI _EJx, Bjorn Helgaas, 2012/05/24