1 files changed, 196 insertions, 331 deletions

diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index aee6a0acbbe9..bccc27ee1030 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -58,71 +58,59 @@
 
 static LIST_HEAD(bridge_list);
 static DEFINE_MUTEX(bridge_mutex);
-static DEFINE_MUTEX(acpiphp_context_lock);
 
-static void handle_hotplug_event(acpi_handle handle, u32 type, void *data);
+static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type);
+static void acpiphp_post_dock_fixup(struct acpi_device *adev);
 static void acpiphp_sanitize_bus(struct pci_bus *bus);
 static void acpiphp_set_hpp_values(struct pci_bus *bus);
-static void hotplug_event(acpi_handle handle, u32 type, void *data);
+static void hotplug_event(u32 type, struct acpiphp_context *context);
 static void free_bridge(struct kref *kref);
 
-static void acpiphp_context_handler(acpi_handle handle, void *context)
-{
-        /* Intentionally empty. */
-}
-
 /**
  * acpiphp_init_context - Create hotplug context and grab a reference to it.
- * @handle: ACPI object handle to create the context for.
+ * @adev: ACPI device object to create the context for.
  *
- * Call under acpiphp_context_lock.
+ * Call under acpi_hp_context_lock.
  */
-static struct acpiphp_context *acpiphp_init_context(acpi_handle handle)
+static struct acpiphp_context *acpiphp_init_context(struct acpi_device *adev)
 {
         struct acpiphp_context *context;
-        acpi_status status;
 
         context = kzalloc(sizeof(*context), GFP_KERNEL);
         if (!context)
                 return NULL;
 
-        context->handle = handle;
         context->refcount = 1;
-        status = acpi_attach_data(handle, acpiphp_context_handler, context);
-        if (ACPI_FAILURE(status)) {
-                kfree(context);
-                return NULL;
-        }
+        acpi_set_hp_context(adev, &context->hp, acpiphp_hotplug_notify, NULL,
+                            acpiphp_post_dock_fixup);
         return context;
 }
 
 /**
  * acpiphp_get_context - Get hotplug context and grab a reference to it.
- * @handle: ACPI object handle to get the context for.
+ * @adev: ACPI device object to get the context for.
  *
- * Call under acpiphp_context_lock.
+ * Call under acpi_hp_context_lock.
  */
-static struct acpiphp_context *acpiphp_get_context(acpi_handle handle)
+static struct acpiphp_context *acpiphp_get_context(struct acpi_device *adev)
 {
-        struct acpiphp_context *context = NULL;
-        acpi_status status;
-        void *data;
+        struct acpiphp_context *context;
 
-        status = acpi_get_data(handle, acpiphp_context_handler, &data);
-        if (ACPI_SUCCESS(status)) {
-                context = data;
-                context->refcount++;
-        }
+        if (!adev->hp)
+                return NULL;
+
+        context = to_acpiphp_context(adev->hp);
+        context->refcount++;
         return context;
 }
 
 /**
  * acpiphp_put_context - Drop a reference to ACPI hotplug context.
- * @handle: ACPI object handle to put the context for.
+ * @context: ACPI hotplug context to drop a reference to.
  *
  * The context object is removed if there are no more references to it.
  *
- * Call under acpiphp_context_lock.
+ * Call under acpi_hp_context_lock.
  */
 static void acpiphp_put_context(struct acpiphp_context *context)
 {
@@ -130,7 +118,7 @@ static void acpiphp_put_context(struct acpiphp_context *context)
                 return;
 
         WARN_ON(context->bridge);
-        acpi_detach_data(context->handle, acpiphp_context_handler);
+        context->hp.self->hp = NULL;
         kfree(context);
 }
 
@@ -144,6 +132,27 @@ static inline void put_bridge(struct acpiphp_bridge *bridge)
         kref_put(&bridge->ref, free_bridge);
 }
 
+static struct acpiphp_context *acpiphp_grab_context(struct acpi_device *adev)
+{
+        struct acpiphp_context *context;
+
+        acpi_lock_hp_context();
+        context = acpiphp_get_context(adev);
+        if (!context || context->func.parent->is_going_away) {
+                acpi_unlock_hp_context();
+                return NULL;
+        }
+        get_bridge(context->func.parent);
+        acpiphp_put_context(context);
+        acpi_unlock_hp_context();
+        return context;
+}
+
+static void acpiphp_let_context_go(struct acpiphp_context *context)
+{
+        put_bridge(context->func.parent);
+}
+
 static void free_bridge(struct kref *kref)
 {
         struct acpiphp_context *context;
@@ -151,7 +160,7 @@ static void free_bridge(struct kref *kref)
         struct acpiphp_slot *slot, *next;
         struct acpiphp_func *func, *tmp;
 
-        mutex_lock(&acpiphp_context_lock);
+        acpi_lock_hp_context();
 
         bridge = container_of(kref, struct acpiphp_bridge, ref);
 
@@ -175,31 +184,32 @@ static void free_bridge(struct kref *kref)
         pci_dev_put(bridge->pci_dev);
         kfree(bridge);
 
-        mutex_unlock(&acpiphp_context_lock);
+        acpi_unlock_hp_context();
 }
 
-/*
- * the _DCK method can do funny things... and sometimes not
- * hah-hah funny.
+/**
+ * acpiphp_post_dock_fixup - Post-dock fixups for PCI devices.
+ * @adev: ACPI device object corresponding to a PCI device.
  *
- * TBD - figure out a way to only call fixups for
- * systems that require them.
+ * TBD - figure out a way to only call fixups for systems that require them.
  */
-static void post_dock_fixups(acpi_handle not_used, u32 event, void *data)
+static void acpiphp_post_dock_fixup(struct acpi_device *adev)
 {
-        struct acpiphp_context *context = data;
-        struct pci_bus *bus = context->func.slot->bus;
+        struct acpiphp_context *context = acpiphp_grab_context(adev);
+        struct pci_bus *bus;
         u32 buses;
 
-        if (!bus->self)
+        if (!context)
                 return;
 
+        bus = context->func.slot->bus;
+        if (!bus->self)
+                goto out;
+
         /* fixup bad _DCK function that rewrites
          * secondary bridge on slot
          */
-        pci_read_config_dword(bus->self,
-                        PCI_PRIMARY_BUS,
-                        &buses);
+        pci_read_config_dword(bus->self, PCI_PRIMARY_BUS, &buses);
 
         if (((buses >> 8) & 0xff) != bus->busn_res.start) {
                 buses = (buses & 0xff000000)
@@ -208,13 +218,10 @@ static void post_dock_fixups(acpi_handle not_used, u32 event, void *data)
                         | ((unsigned int)(bus->busn_res.end) << 16);
                 pci_write_config_dword(bus->self, PCI_PRIMARY_BUS, buses);
         }
-}
-
 
-static const struct acpi_dock_ops acpiphp_dock_ops = {
-        .fixup = post_dock_fixups,
-        .handler = hotplug_event,
-};
+ out:
+        acpiphp_let_context_go(context);
+}
 
 /* Check whether the PCI device is managed by native PCIe hotplug driver */
 static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
@@ -245,26 +252,19 @@ static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev)
         return true;
 }
 
-static void acpiphp_dock_init(void *data)
-{
-        struct acpiphp_context *context = data;
-
-        get_bridge(context->func.parent);
-}
-
-static void acpiphp_dock_release(void *data)
-{
-        struct acpiphp_context *context = data;
-
-        put_bridge(context->func.parent);
-}
-
-/* callback routine to register each ACPI PCI slot object */
-static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
-                                 void **rv)
+/**
+ * acpiphp_add_context - Add ACPIPHP context to an ACPI device object.
+ * @handle: ACPI handle of the object to add a context to.
+ * @lvl: Not used.
+ * @data: The object's parent ACPIPHP bridge.
+ * @rv: Not used.
+ */
+static acpi_status acpiphp_add_context(acpi_handle handle, u32 lvl, void *data,
+                                       void **rv)
 {
         struct acpiphp_bridge *bridge = data;
         struct acpiphp_context *context;
+        struct acpi_device *adev;
         struct acpiphp_slot *slot;
         struct acpiphp_func *newfunc;
         acpi_status status = AE_OK;
@@ -274,9 +274,6 @@ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
         struct pci_dev *pdev = bridge->pci_dev;
         u32 val;
 
-        if (pdev && device_is_managed_by_native_pciehp(pdev))
-                return AE_OK;
-
         status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
         if (ACPI_FAILURE(status)) {
                 if (status != AE_NOT_FOUND)
@@ -284,31 +281,34 @@ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
                                 "can't evaluate _ADR (%#x)\n", status);
                 return AE_OK;
         }
+        if (acpi_bus_get_device(handle, &adev))
+                return AE_OK;
 
         device = (adr >> 16) & 0xffff;
         function = adr & 0xffff;
 
-        mutex_lock(&acpiphp_context_lock);
-        context = acpiphp_init_context(handle);
+        acpi_lock_hp_context();
+        context = acpiphp_init_context(adev);
         if (!context) {
-                mutex_unlock(&acpiphp_context_lock);
+                acpi_unlock_hp_context();
                 acpi_handle_err(handle, "No hotplug context\n");
                 return AE_NOT_EXIST;
         }
         newfunc = &context->func;
         newfunc->function = function;
         newfunc->parent = bridge;
-        mutex_unlock(&acpiphp_context_lock);
+        acpi_unlock_hp_context();
 
-        if (acpi_has_method(handle, "_EJ0"))
+        /*
+         * If this is a dock device, its _EJ0 should be executed by the dock
+         * notify handler after calling _DCK.
+         */
+        if (!is_dock_device(adev) && acpi_has_method(handle, "_EJ0"))
                 newfunc->flags = FUNC_HAS_EJ0;
 
         if (acpi_has_method(handle, "_STA"))
                 newfunc->flags |= FUNC_HAS_STA;
 
-        if (acpi_has_method(handle, "_DCK"))
-                newfunc->flags |= FUNC_HAS_DCK;
-
         /* search for objects that share the same slot */
         list_for_each_entry(slot, &bridge->slots, node)
                 if (slot->device == device)
@@ -316,19 +316,26 @@ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
 
         slot = kzalloc(sizeof(struct acpiphp_slot), GFP_KERNEL);
         if (!slot) {
-                status = AE_NO_MEMORY;
-                goto err;
+                acpi_lock_hp_context();
+                acpiphp_put_context(context);
+                acpi_unlock_hp_context();
+                return AE_NO_MEMORY;
         }
 
         slot->bus = bridge->pci_bus;
         slot->device = device;
         INIT_LIST_HEAD(&slot->funcs);
-        mutex_init(&slot->crit_sect);
 
         list_add_tail(&slot->node, &bridge->slots);
 
-        /* Register slots for ejectable functions only. */
-        if (acpi_pci_check_ejectable(pbus, handle)  || is_dock_device(handle)) {
+        /*
+         * Expose slots to user space for functions that have _EJ0 or _RMV or
+         * are located in dock stations.  Do not expose them for devices handled
+         * by the native PCIe hotplug (PCIeHP), becuase that code is supposed to
+         * expose slots to user space in those cases.
+         */
+        if ((acpi_pci_check_ejectable(pbus, handle) || is_dock_device(adev))
+            && !(pdev && device_is_managed_by_native_pciehp(pdev))) {
                 unsigned long long sun;
                 int retval;
 
@@ -362,44 +369,16 @@ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *data,
                                        &val, 60*1000))
                 slot->flags |= SLOT_ENABLED;
 
-        if (is_dock_device(handle)) {
-                /* we don't want to call this device's _EJ0
-                 * because we want the dock notify handler
-                 * to call it after it calls _DCK
-                 */
-                newfunc->flags &= ~FUNC_HAS_EJ0;
-                if (register_hotplug_dock_device(handle,
-                        &acpiphp_dock_ops, context,
-                        acpiphp_dock_init, acpiphp_dock_release))
-                        pr_debug("failed to register dock device\n");
-        }
-
-        /* install notify handler */
-        if (!(newfunc->flags & FUNC_HAS_DCK)) {
-                status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
-                                                     handle_hotplug_event,
-                                                     context);
-                if (ACPI_FAILURE(status))
-                        acpi_handle_err(handle,
-                                        "failed to install notify handler\n");
-        }
-
         return AE_OK;
-
- err:
-        mutex_lock(&acpiphp_context_lock);
-        acpiphp_put_context(context);
-        mutex_unlock(&acpiphp_context_lock);
-        return status;
 }
 
-static struct acpiphp_bridge *acpiphp_handle_to_bridge(acpi_handle handle)
+static struct acpiphp_bridge *acpiphp_dev_to_bridge(struct acpi_device *adev)
 {
         struct acpiphp_context *context;
         struct acpiphp_bridge *bridge = NULL;
 
-        mutex_lock(&acpiphp_context_lock);
-        context = acpiphp_get_context(handle);
+        acpi_lock_hp_context();
+        context = acpiphp_get_context(adev);
         if (context) {
                 bridge = context->bridge;
                 if (bridge)
@@ -407,7 +386,7 @@ static struct acpiphp_bridge *acpiphp_handle_to_bridge(acpi_handle handle)
 
                 acpiphp_put_context(context);
         }
-        mutex_unlock(&acpiphp_context_lock);
+        acpi_unlock_hp_context();
         return bridge;
 }
 
@@ -415,22 +394,15 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
 {
         struct acpiphp_slot *slot;
         struct acpiphp_func *func;
-        acpi_status status;
 
         list_for_each_entry(slot, &bridge->slots, node) {
                 list_for_each_entry(func, &slot->funcs, sibling) {
-                        acpi_handle handle = func_to_handle(func);
-
-                        if (is_dock_device(handle))
-                                unregister_hotplug_dock_device(handle);
+                        struct acpi_device *adev = func_to_acpi_device(func);
 
-                        if (!(func->flags & FUNC_HAS_DCK)) {
-                                status = acpi_remove_notify_handler(handle,
-                                                        ACPI_SYSTEM_NOTIFY,
-                                                        handle_hotplug_event);
-                                if (ACPI_FAILURE(status))
-                                        pr_err("failed to remove notify handler\n");
-                        }
+                        acpi_lock_hp_context();
+                        adev->hp->notify = NULL;
+                        adev->hp->fixup = NULL;
+                        acpi_unlock_hp_context();
                 }
                 slot->flags |= SLOT_IS_GOING_AWAY;
                 if (slot->slot)
@@ -441,7 +413,9 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
         list_del(&bridge->list);
         mutex_unlock(&bridge_mutex);
 
+        acpi_lock_hp_context();
         bridge->is_going_away = true;
+        acpi_unlock_hp_context();
 }
 
 /**
@@ -471,33 +445,6 @@ static unsigned char acpiphp_max_busnr(struct pci_bus *bus)
         return max;
 }
 
-/**
- * acpiphp_bus_trim - Trim device objects in an ACPI namespace subtree.
- * @handle: ACPI device object handle to start from.
- */
-static void acpiphp_bus_trim(acpi_handle handle)
-{
-        struct acpi_device *adev = NULL;
-
-        acpi_bus_get_device(handle, &adev);
-        if (adev)
-                acpi_bus_trim(adev);
-}
-
-/**
- * acpiphp_bus_add - Scan ACPI namespace subtree.
- * @handle: ACPI object handle to start the scan from.
- */
-static void acpiphp_bus_add(acpi_handle handle)
-{
-        struct acpi_device *adev = NULL;
-
-        acpi_bus_scan(handle);
-        acpi_bus_get_device(handle, &adev);
-        if (acpi_device_enumerated(adev))
-                acpi_device_set_power(adev, ACPI_STATE_D0);
-}
-
 static void acpiphp_set_acpi_region(struct acpiphp_slot *slot)
 {
         struct acpiphp_func *func;
@@ -537,9 +484,13 @@ static int acpiphp_rescan_slot(struct acpiphp_slot *slot)
 {
         struct acpiphp_func *func;
 
-        list_for_each_entry(func, &slot->funcs, sibling)
-                acpiphp_bus_add(func_to_handle(func));
+        list_for_each_entry(func, &slot->funcs, sibling) {
+                struct acpi_device *adev = func_to_acpi_device(func);
 
+                acpi_bus_scan(adev->handle);
+                if (acpi_device_enumerated(adev))
+                        acpi_device_set_power(adev, ACPI_STATE_D0);
+        }
         return pci_scan_slot(slot->bus, PCI_DEVFN(slot->device, 0));
 }
 
@@ -604,32 +555,15 @@ 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
@@ -637,22 +571,18 @@ 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));
+                acpi_bus_trim(func_to_acpi_device(func));
 
         slot->flags &= (~SLOT_ENABLED);
 }
 
-static bool acpiphp_no_hotplug(acpi_handle handle)
+static bool acpiphp_no_hotplug(struct acpi_device *adev)
 {
-        struct acpi_device *adev = NULL;
-
-        acpi_bus_get_device(handle, &adev);
         return adev && adev->flags.no_hotplug;
 }
 
@@ -661,7 +591,7 @@ static bool slot_no_hotplug(struct acpiphp_slot *slot)
         struct acpiphp_func *func;
 
         list_for_each_entry(func, &slot->funcs, sibling)
-                if (acpiphp_no_hotplug(func_to_handle(func)))
+                if (acpiphp_no_hotplug(func_to_acpi_device(func)))
                         return true;
 
         return false;
@@ -709,40 +639,48 @@ static unsigned int get_slot_status(struct acpiphp_slot *slot)
         return (unsigned int)sta;
 }
 
+static inline bool device_status_valid(unsigned int sta)
+{
+        /*
+         * ACPI spec says that _STA may return bit 0 clear with bit 3 set
+         * if the device is valid but does not require a device driver to be
+         * loaded (Section 6.3.7 of ACPI 5.0A).
+         */
+        unsigned int mask = ACPI_STA_DEVICE_ENABLED | ACPI_STA_DEVICE_FUNCTIONING;
+        return (sta & mask) == mask;
+}
+
 /**
  * trim_stale_devices - remove PCI devices that are not responding.
  * @dev: PCI device to start walking the hierarchy from.
  */
 static void trim_stale_devices(struct pci_dev *dev)
 {
-        acpi_handle handle = ACPI_HANDLE(&dev->dev);
+        struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
         struct pci_bus *bus = dev->subordinate;
         bool alive = false;
 
-        if (handle) {
+        if (adev) {
                 acpi_status status;
                 unsigned long long sta;
 
-                status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
-                alive = (ACPI_SUCCESS(status) && sta == ACPI_STA_ALL)
-                        || acpiphp_no_hotplug(handle);
+                status = acpi_evaluate_integer(adev->handle, "_STA", NULL, &sta);
+                alive = (ACPI_SUCCESS(status) && device_status_valid(sta))
+                        || acpiphp_no_hotplug(adev);
         }
-        if (!alive) {
-                u32 v;
+        if (!alive)
+                alive = pci_device_is_present(dev);
 
-                /* Check if the device responds. */
-                alive = pci_bus_read_dev_vendor_id(dev->bus, dev->devfn, &v, 0);
-        }
         if (!alive) {
                 pci_stop_and_remove_bus_device(dev);
-                if (handle)
-                        acpiphp_bus_trim(handle);
+                if (adev)
+                        acpi_bus_trim(adev);
         } else if (bus) {
                 struct pci_dev *child, *tmp;
 
                 /* The device is a bridge. so check the bus below it. */
                 pm_runtime_get_sync(&dev->dev);
-                list_for_each_entry_safe(child, tmp, &bus->devices, bus_list)
+                list_for_each_entry_safe_reverse(child, tmp, &bus->devices, bus_list)
                         trim_stale_devices(child);
 
                 pm_runtime_put(&dev->dev);
@@ -768,13 +706,12 @@ static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
                 struct pci_bus *bus = slot->bus;
                 struct pci_dev *dev, *tmp;
 
-                mutex_lock(&slot->crit_sect);
                 if (slot_no_hotplug(slot)) {
                         ; /* do nothing */
-                } else if (get_slot_status(slot) == ACPI_STA_ALL) {
+                } else if (device_status_valid(get_slot_status(slot))) {
                         /* remove stale devices if any */
-                        list_for_each_entry_safe(dev, tmp, &bus->devices,
-                                                 bus_list)
+                        list_for_each_entry_safe_reverse(dev, tmp,
+                                                         &bus->devices, bus_list)
                                 if (PCI_SLOT(dev->devfn) == slot->device)
                                         trim_stale_devices(dev);
 
@@ -783,7 +720,6 @@ static void acpiphp_check_bridge(struct acpiphp_bridge *bridge)
                 } else {
                         disable_slot(slot);
                 }
-                mutex_unlock(&slot->crit_sect);
         }
 }
 
@@ -805,7 +741,7 @@ static void acpiphp_sanitize_bus(struct pci_bus *bus)
         int i;
         unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM;
 
-        list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
+        list_for_each_entry_safe_reverse(dev, tmp, &bus->devices, bus_list) {
                 for (i=0; i<PCI_BRIDGE_RESOURCES; i++) {
                         struct resource *res = &dev->resource[i];
                         if ((res->flags & type_mask) && !res->start &&
@@ -823,186 +759,112 @@ static void acpiphp_sanitize_bus(struct pci_bus *bus)
  * ACPI event handlers
  */
 
-void acpiphp_check_host_bridge(acpi_handle handle)
+void acpiphp_check_host_bridge(struct acpi_device *adev)
 {
         struct acpiphp_bridge *bridge;
 
-        bridge = acpiphp_handle_to_bridge(handle);
+        bridge = acpiphp_dev_to_bridge(adev);
         if (bridge) {
+                pci_lock_rescan_remove();
+
                 acpiphp_check_bridge(bridge);
+
+                pci_unlock_rescan_remove();
                 put_bridge(bridge);
         }
 }
 
 static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot);
 
-static void hotplug_event(acpi_handle handle, u32 type, void *data)
+static void hotplug_event(u32 type, struct acpiphp_context *context)
 {
-        struct acpiphp_context *context = data;
+        acpi_handle handle = context->hp.self->handle;
         struct acpiphp_func *func = &context->func;
+        struct acpiphp_slot *slot = func->slot;
         struct acpiphp_bridge *bridge;
-        char objname[64];
-        struct acpi_buffer buffer = { .length = sizeof(objname),
-                                      .pointer = objname };
 
-        mutex_lock(&acpiphp_context_lock);
+        acpi_lock_hp_context();
         bridge = context->bridge;
         if (bridge)
                 get_bridge(bridge);
 
-        mutex_unlock(&acpiphp_context_lock);
+        acpi_unlock_hp_context();
 
-        acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+        pci_lock_rescan_remove();
 
         switch (type) {
         case ACPI_NOTIFY_BUS_CHECK:
                 /* bus re-enumerate */
-                pr_debug("%s: Bus check notify on %s\n", __func__, objname);
-                pr_debug("%s: re-enumerating slots under %s\n",
-                         __func__, objname);
-                if (bridge) {
+                acpi_handle_debug(handle, "Bus check in %s()\n", __func__);
+                if (bridge)
                         acpiphp_check_bridge(bridge);
-                } else {
-                        struct acpiphp_slot *slot = func->slot;
-
-                        if (slot->flags & SLOT_IS_GOING_AWAY)
-                                break;
-
-                        mutex_lock(&slot->crit_sect);
+                else if (!(slot->flags & SLOT_IS_GOING_AWAY))
                         enable_slot(slot);
-                        mutex_unlock(&slot->crit_sect);
-                }
+
                 break;
 
         case ACPI_NOTIFY_DEVICE_CHECK:
                 /* device check */
-                pr_debug("%s: Device check notify on %s\n", __func__, objname);
+                acpi_handle_debug(handle, "Device check in %s()\n", __func__);
                 if (bridge) {
                         acpiphp_check_bridge(bridge);
-                } else {
-                        struct acpiphp_slot *slot = func->slot;
-                        int ret;
-
-                        if (slot->flags & SLOT_IS_GOING_AWAY)
-                                break;
-
+                } else if (!(slot->flags & SLOT_IS_GOING_AWAY)) {
                         /*
                          * Check if anything has changed in the slot and rescan
                          * from the parent if that's the case.
                          */
-                        mutex_lock(&slot->crit_sect);
-                        ret = acpiphp_rescan_slot(slot);
-                        mutex_unlock(&slot->crit_sect);
-                        if (ret)
+                        if (acpiphp_rescan_slot(slot))
                                 acpiphp_check_bridge(func->parent);
                 }
                 break;
 
         case ACPI_NOTIFY_EJECT_REQUEST:
                 /* request device eject */
-                pr_debug("%s: Device eject notify on %s\n", __func__, objname);
-                acpiphp_disable_and_eject_slot(func->slot);
+                acpi_handle_debug(handle, "Eject request in %s()\n", __func__);
+                acpiphp_disable_and_eject_slot(slot);
                 break;
         }
 
+        pci_unlock_rescan_remove();
         if (bridge)
                 put_bridge(bridge);
 }
 
-static void hotplug_event_work(void *data, u32 type)
+static int acpiphp_hotplug_notify(struct acpi_device *adev, u32 type)
 {
-        struct acpiphp_context *context = data;
-        acpi_handle handle = context->handle;
-
-        acpi_scan_lock_acquire();
-        pci_lock_rescan_remove();
+        struct acpiphp_context *context;
 
-        hotplug_event(handle, type, context);
+        context = acpiphp_grab_context(adev);
+        if (!context)
+                return -ENODATA;
 
-        pci_unlock_rescan_remove();
-        acpi_scan_lock_release();
-        acpi_evaluate_hotplug_ost(handle, type, ACPI_OST_SC_SUCCESS, NULL);
-        put_bridge(context->func.parent);
+        hotplug_event(type, context);
+        acpiphp_let_context_go(context);
+        return 0;
 }
 
 /**
- * handle_hotplug_event - handle ACPI hotplug event
- * @handle: Notify()'ed acpi_handle
- * @type: Notify code
- * @data: pointer to acpiphp_context structure
+ * acpiphp_enumerate_slots - Enumerate PCI slots for a given bus.
+ * @bus: PCI bus to enumerate the slots for.
  *
- * Handles ACPI event notification on slots.
- */
-static void handle_hotplug_event(acpi_handle handle, u32 type, void *data)
-{
-        struct acpiphp_context *context;
-        u32 ost_code = ACPI_OST_SC_SUCCESS;
-
-        switch (type) {
-        case ACPI_NOTIFY_BUS_CHECK:
-        case ACPI_NOTIFY_DEVICE_CHECK:
-                break;
-        case ACPI_NOTIFY_EJECT_REQUEST:
-                ost_code = ACPI_OST_SC_EJECT_IN_PROGRESS;
-                acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
-                break;
-
-        case ACPI_NOTIFY_DEVICE_WAKE:
-                return;
-
-        case ACPI_NOTIFY_FREQUENCY_MISMATCH:
-                acpi_handle_err(handle, "Device cannot be configured due "
-                                "to a frequency mismatch\n");
-                goto out;
-
-        case ACPI_NOTIFY_BUS_MODE_MISMATCH:
-                acpi_handle_err(handle, "Device cannot be configured due "
-                                "to a bus mode mismatch\n");
-                goto out;
-
-        case ACPI_NOTIFY_POWER_FAULT:
-                acpi_handle_err(handle, "Device has suffered a power fault\n");
-                goto out;
-
-        default:
-                acpi_handle_warn(handle, "Unsupported event type 0x%x\n", type);
-                ost_code = ACPI_OST_SC_UNRECOGNIZED_NOTIFY;
-                goto out;
-        }
-
-        mutex_lock(&acpiphp_context_lock);
-        context = acpiphp_get_context(handle);
-        if (context && !WARN_ON(context->handle != handle)) {
-                get_bridge(context->func.parent);
-                acpiphp_put_context(context);
-                acpi_hotplug_execute(hotplug_event_work, context, type);
-                mutex_unlock(&acpiphp_context_lock);
-                return;
-        }
-        mutex_unlock(&acpiphp_context_lock);
-        ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE;
-
- out:
-        acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
-}
-
-/*
- * Create hotplug slots for the PCI bus.
- * It should always return 0 to avoid skipping following notifiers.
+ * A "slot" is an object associated with a PCI device number.  All functions
+ * (PCI devices) with the same bus and device number belong to the same slot.
  */
 void acpiphp_enumerate_slots(struct pci_bus *bus)
 {
         struct acpiphp_bridge *bridge;
+        struct acpi_device *adev;
         acpi_handle handle;
         acpi_status status;
 
         if (acpiphp_disabled)
                 return;
 
-        handle = ACPI_HANDLE(bus->bridge);
-        if (!handle)
+        adev = ACPI_COMPANION(bus->bridge);
+        if (!adev)
                 return;
 
+        handle = adev->handle;
         bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
         if (!bridge) {
                 acpi_handle_err(handle, "No memory for bridge object\n");
@@ -1030,10 +892,10 @@ void acpiphp_enumerate_slots(struct pci_bus *bus)
                  * parent is going to be handled by pciehp, in which case this
                  * bridge is not interesting to us either.
                  */
-                mutex_lock(&acpiphp_context_lock);
-                context = acpiphp_get_context(handle);
+                acpi_lock_hp_context();
+                context = acpiphp_get_context(adev);
                 if (!context) {
-                        mutex_unlock(&acpiphp_context_lock);
+                        acpi_unlock_hp_context();
                         put_device(&bus->dev);
                         pci_dev_put(bridge->pci_dev);
                         kfree(bridge);
@@ -1043,17 +905,17 @@ void acpiphp_enumerate_slots(struct pci_bus *bus)
                 context->bridge = bridge;
                 /* Get a reference to the parent bridge. */
                 get_bridge(context->func.parent);
-                mutex_unlock(&acpiphp_context_lock);
+                acpi_unlock_hp_context();
         }
 
-        /* must be added to the list prior to calling register_slot */
+        /* Must be added to the list prior to calling acpiphp_add_context(). */
         mutex_lock(&bridge_mutex);
         list_add(&bridge->list, &bridge_list);
         mutex_unlock(&bridge_mutex);
 
         /* register all slot objects under this bridge */
         status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
-                                     register_slot, NULL, bridge, NULL);
+                                     acpiphp_add_context, NULL, bridge, NULL);
         if (ACPI_FAILURE(status)) {
                 acpi_handle_err(handle, "failed to register slots\n");
                 cleanup_bridge(bridge);
@@ -1061,7 +923,10 @@ void acpiphp_enumerate_slots(struct pci_bus *bus)
         }
 }
 
-/* Destroy hotplug slots associated with the PCI bus */
+/**
+ * acpiphp_remove_slots - Remove slot objects associated with a given bus.
+ * @bus: PCI bus to remove the slot objects for.
+ */
 void acpiphp_remove_slots(struct pci_bus *bus)
 {
         struct acpiphp_bridge *bridge;
@@ -1092,13 +957,10 @@ int acpiphp_enable_slot(struct acpiphp_slot *slot)
         if (slot->flags & SLOT_IS_GOING_AWAY)
                 return -ENODEV;
 
-        mutex_lock(&slot->crit_sect);
         /* configure all functions */
         if (!(slot->flags & SLOT_ENABLED))
                 enable_slot(slot);
 
-        mutex_unlock(&slot->crit_sect);
-
         pci_unlock_rescan_remove();
         return 0;
 }
@@ -1114,8 +976,6 @@ static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
         if (slot->flags & SLOT_IS_GOING_AWAY)
                 return -ENODEV;
 
-        mutex_lock(&slot->crit_sect);
-
         /* unconfigure all functions */
         disable_slot(slot);
 
@@ -1129,7 +989,6 @@ static int acpiphp_disable_and_eject_slot(struct acpiphp_slot *slot)
                         break;
                 }
 
-        mutex_unlock(&slot->crit_sect);
         return 0;
 }
 
@@ -1137,9 +996,15 @@ int acpiphp_disable_slot(struct acpiphp_slot *slot)
 {
         int ret;
 
+        /*
+         * Acquire acpi_scan_lock to ensure that the execution of _EJ0 in
+         * acpiphp_disable_and_eject_slot() will be synchronized properly.
+         */
+        acpi_scan_lock_acquire();
         pci_lock_rescan_remove();
         ret = acpiphp_disable_and_eject_slot(slot);
         pci_unlock_rescan_remove();
+        acpi_scan_lock_release();
         return ret;
 }