diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-02-04 00:37:02 +0100 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2014-02-05 17:40:24 +0100 |
commit | 1c0c5443de5f1f03ae2abce569fb673377f0fd0e (patch) | |
tree | 62222070f5db7109408148498eea7f34e8d64be1 /drivers/pci | |
parent | af9d8adc6b832003bbe3d83fde665ae6b4f072eb (diff) |
ACPI / hotplug / PCI: Simplify disable_slot()
After recent PCI core changes related to the rescan/remove locking,
the ACPIPHP's disable_slot() function is only called under the
general PCI rescan/remove lock, so it doesn't have to use
dev_in_slot() any more to avoid race conditions. Make it simply
walk the devices on the bus and drop the ones in the slot being
disabled and drop dev_in_slot() which has no more users.
Moreover, to avoid problems described in the changelog of commit
29ed1f29b68a (PCI: pciehp: Fix null pointer deref when hot-removing
SR-IOV device), make disable_slot() carry out the list walk in
reverse order.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/hotplug/acpiphp_glue.c | 28 |
1 files changed, 5 insertions, 23 deletions
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index e2a783fdb98..f24c19c8f8c 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -625,32 +625,15 @@ static void __ref enable_slot(struct acpiphp_slot *slot) } } -/* 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->bus; - struct pci_dev *dev; - struct pci_dev *ret = NULL; - - down_read(&pci_bus_sem); - list_for_each_entry(dev, &bus->devices, bus_list) - if (PCI_SLOT(dev->devfn) == slot->device) { - ret = pci_dev_get(dev); - break; - } - up_read(&pci_bus_sem); - - return ret; -} - /** * disable_slot - disable a slot * @slot: ACPI PHP slot */ static void disable_slot(struct acpiphp_slot *slot) { + struct pci_bus *bus = slot->bus; + struct pci_dev *dev, *prev; struct acpiphp_func *func; - struct pci_dev *pdev; /* * enable_slot() enumerates all functions in this device via @@ -658,10 +641,9 @@ static void disable_slot(struct acpiphp_slot *slot) * methods (_EJ0, etc.) or not. Therefore, we remove all functions * here. */ - while ((pdev = dev_in_slot(slot))) { - pci_stop_and_remove_bus_device(pdev); - pci_dev_put(pdev); - } + list_for_each_entry_safe_reverse(dev, prev, &bus->devices, bus_list) + if (PCI_SLOT(dev->devfn) == slot->device) + pci_stop_and_remove_bus_device(dev); list_for_each_entry(func, &slot->funcs, sibling) acpiphp_bus_trim(func_to_handle(func)); |