Currently the pci_slot driver doesn't update PCI slot information
when PCI device hotplug event happens, which may cause memory leak
and returning stale information to user.
So hook the BUS_NOTIFY_ADD_DEVICE/BUS_NOTIFY_DEL_DEVICE events to
update PCI slot information when PCI hotplug event happens.
Signed-off-by: Jiang Liu <jiang....@huawei.com>
Signed-off-by: Yijing Wang <wangyij...@huawei.com>
---
drivers/acpi/pci_slot.c | 86 ++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 78 insertions(+), 8 deletions(-)
diff --git a/drivers/acpi/pci_slot.c b/drivers/acpi/pci_slot.c
index e50e31a..96dcc19 100644
--- a/drivers/acpi/pci_slot.c
+++ b/drivers/acpi/pci_slot.c
@@ -32,6 +32,7 @@
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
+#include <linux/pci-acpi.h>
#include <linux/dmi.h>
static bool debug;
@@ -123,12 +124,7 @@ struct callback_args {
/*
* register_slot
*
- * Called once for each SxFy object in the namespace. Don't worry about
- * calling pci_create_slot multiple times for the same pci_bus:device,
- * since each subsequent call simply bumps the refcount on the pci_slot.
- *
- * The number of calls to pci_destroy_slot from unregister_slot is
- * symmetrical.
+ * Called once for each SxFy object in the namespace.
*/
static acpi_status
register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
@@ -145,6 +141,15 @@ register_slot(acpi_handle handle, u32 lvl, void *context,
void **rv)
if (device < 0)
return AE_OK;
+ /* Avoid duplicated records for the same slot */
+ list_for_each_entry(slot, &slot_list, list) {
+ pci_slot = slot->pci_slot;
+ if (pci_slot && pci_slot->bus == pci_bus &&
+ pci_slot->number == device) {
+ return AE_OK;
+ }
+ }
+
slot = kmalloc(sizeof(*slot), GFP_KERNEL);
if (!slot) {
err("%s: cannot allocate memory\n", __func__);
@@ -162,9 +167,7 @@ register_slot(acpi_handle handle, u32 lvl, void *context,
void **rv)
slot->root_handle = parent_context->root_handle;
slot->pci_slot = pci_slot;
INIT_LIST_HEAD(&slot->list);
- mutex_lock(&slot_list_lock);
list_add(&slot->list, &slot_list);
- mutex_unlock(&slot_list_lock);
get_device(&pci_bus->dev);
@@ -299,7 +302,9 @@ acpi_pci_slot_add(acpi_handle handle)
{
acpi_status status;
+ mutex_lock(&slot_list_lock);
status = walk_root_bridge(handle, register_slot);
+ mutex_unlock(&slot_list_lock);
if (ACPI_FAILURE(status))
err("%s: register_slot failure - %d\n", __func__, status);
@@ -354,17 +359,82 @@ static struct dmi_system_id acpi_pci_slot_dmi_table[]
__initdata = {
{}
};
+static void acpi_pci_slot_notify_add(struct pci_dev *dev)
+{
+ acpi_handle handle;
+ struct callback_args context;
+
+ if (!dev->subordinate)
+ return;
+
+ mutex_lock(&slot_list_lock);
+ handle = DEVICE_ACPI_HANDLE(&dev->dev);
+ context.root_handle = acpi_find_root_bridge_handle(dev);
+ if (handle && context.root_handle) {
+ context.pci_bus = dev->subordinate;
+ context.user_function = register_slot;
+ acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
+ register_slot, NULL, &context, NULL);
+ }
+ mutex_unlock(&slot_list_lock);
+}
+
+static void acpi_pci_slot_notify_del(struct pci_dev *dev)
+{
+ struct acpi_pci_slot *slot, *tmp;
+ struct pci_bus *bus = dev->subordinate;
+
+ if (!bus)
+ return;
+
+ mutex_lock(&slot_list_lock);
+ list_for_each_entry_safe(slot, tmp, &slot_list, list)
+ if (slot->pci_slot && slot->pci_slot->bus == bus) {
+ list_del(&slot->list);
+ pci_destroy_slot(slot->pci_slot);
+ put_device(&bus->dev);
+ kfree(slot);
+ }
+ mutex_unlock(&slot_list_lock);
+}
+
+static int acpi_pci_slot_notify_fn(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct device *dev = data;
+
+ switch (event) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ acpi_pci_slot_notify_add(to_pci_dev(dev));
+ break;
+ case BUS_NOTIFY_DEL_DEVICE:
+ acpi_pci_slot_notify_del(to_pci_dev(dev));
+ break;
+ default:
+ return NOTIFY_DONE;
+ }
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block acpi_pci_slot_notifier = {
+ .notifier_call = &acpi_pci_slot_notify_fn,
+};
+
static int __init
acpi_pci_slot_init(void)
{
dmi_check_system(acpi_pci_slot_dmi_table);
acpi_pci_register_driver(&acpi_pci_slot_driver);
+ bus_register_notifier(&pci_bus_type, &acpi_pci_slot_notifier);
+
return 0;
}
static void __exit
acpi_pci_slot_exit(void)
{
+ bus_unregister_notifier(&pci_bus_type, &acpi_pci_slot_notifier);
acpi_pci_unregister_driver(&acpi_pci_slot_driver);
}
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
