[PATCH] acpiphp: hotplug slot hotplug

o hotplug slots add
  When the hot-added PCI device is p2p bridge, acpiphp calls
  find_p2p_bridge() to add hotplug slots.

o hotplug slots remove
  When the hot-removing PCI device is p2p bridge, acpiphp
  calls cleanup_p2p_bridge() to remove hotplug slots.

o notify handler exchange
  When the p2p bridge is added, acpiphp changes the notify
  hanlder.
  If no bridge device is inserted into the hotpluggable PCI
  slot, acpiphp installs the notify handler for function.
  After the p2p bridge hot-add, acpiphp has to install the
  notify handler for bridge. Because, the role of the
  handlers are not same. The hot-remove case is ditto.
Signed-off-by: MUNEDA Takahiro <muneda.takahiro@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/hotplug/acpiphp.h

@@ -75,6 +75,10 @@ struct acpiphp_bridge {
 	struct list_head list;
 	acpi_handle handle;
 	struct acpiphp_slot *slots;
+
+	/* Ejectable PCI-to-PCI bridge (PCI bridge and PCI function) */
+	struct acpiphp_func *func;
+
 	int type;
 	int nr_slots;
 
@@ -122,6 +126,7 @@ struct acpiphp_slot {
  */
 struct acpiphp_func {
 	struct acpiphp_slot *slot;	/* parent */
+	struct acpiphp_bridge *bridge;	/* Ejectable PCI-to-PCI bridge */
 
 	struct list_head sibling;
 	struct pci_dev *pci_dev;

drivers/pci/hotplug/acpiphp_glue.c

@@ -319,6 +319,13 @@ static void init_bridge_misc(struct acpiphp_bridge *bridge)
 
 	/* install notify handler */
 	if (bridge->type != BRIDGE_TYPE_HOST) {
+		if ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
+			status = acpi_remove_notify_handler(bridge->func->handle,
+						ACPI_SYSTEM_NOTIFY,
+						handle_hotplug_event_func);
+			if (ACPI_FAILURE(status))
+				err("failed to remove notify handler\n");
+		}
 		status = acpi_install_notify_handler(bridge->handle,
 					     ACPI_SYSTEM_NOTIFY,
 					     handle_hotplug_event_bridge,
@@ -331,6 +338,66 @@ static void init_bridge_misc(struct acpiphp_bridge *bridge)
 }
 
 
+/* find acpiphp_func from acpiphp_bridge */
+static struct acpiphp_func *acpiphp_bridge_handle_to_function(acpi_handle handle)
+{
+	struct list_head *node, *l;
+	struct acpiphp_bridge *bridge;
+	struct acpiphp_slot *slot;
+	struct acpiphp_func *func;
+
+	list_for_each(node, &bridge_list) {
+		bridge = list_entry(node, struct acpiphp_bridge, list);
+		for (slot = bridge->slots; slot; slot = slot->next) {
+			list_for_each(l, &slot->funcs) {
+				func = list_entry(l, struct acpiphp_func,
+							sibling);
+				if (func->handle == handle)
+					return func;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+
+static inline void config_p2p_bridge_flags(struct acpiphp_bridge *bridge)
+{
+	acpi_handle dummy_handle;
+
+	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
+					"_STA", &dummy_handle)))
+		bridge->flags |= BRIDGE_HAS_STA;
+
+	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
+					"_EJ0", &dummy_handle)))
+		bridge->flags |= BRIDGE_HAS_EJ0;
+
+	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
+					"_PS0", &dummy_handle)))
+		bridge->flags |= BRIDGE_HAS_PS0;
+
+	if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
+					"_PS3", &dummy_handle)))
+		bridge->flags |= BRIDGE_HAS_PS3;
+
+	/* is this ejectable p2p bridge? */
+	if (bridge->flags & BRIDGE_HAS_EJ0) {
+		struct acpiphp_func *func;
+
+		dbg("found ejectable p2p bridge\n");
+
+		/* make link between PCI bridge and PCI function */
+		func = acpiphp_bridge_handle_to_function(bridge->handle);
+		if (!func)
+			return;
+		bridge->func = func;
+		func->bridge = bridge;
+	}
+}
+
+
 /* allocate and initialize host bridge data structure */
 static void add_host_bridge(acpi_handle *handle, struct pci_bus *pci_bus)
 {
@@ -364,6 +431,7 @@ static void add_p2p_bridge(acpi_handle *handle, struct pci_dev *pci_dev)
 
 	bridge->type = BRIDGE_TYPE_P2P;
 	bridge->handle = handle;
+	config_p2p_bridge_flags(bridge);
 
 	bridge->pci_dev = pci_dev_get(pci_dev);
 	bridge->pci_bus = pci_dev->subordinate;
@@ -423,7 +491,7 @@ find_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
 				     find_p2p_bridge, dev->subordinate, NULL);
 	if (ACPI_FAILURE(status))
-		warn("find_p2p_bridge faied (error code = 0x%x)\n", status);
+		warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
 
  out:
 	pci_dev_put(dev);
@@ -486,7 +554,7 @@ static int add_bridge(acpi_handle handle)
 				     find_p2p_bridge, pci_bus, NULL);
 
 	if (ACPI_FAILURE(status))
-		warn("find_p2p_bridge faied (error code = 0x%x)\n",status);
+		warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
 
 	return 0;
 }
@@ -516,6 +584,16 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
 	if (ACPI_FAILURE(status))
 		err("failed to remove notify handler\n");
 
+	if ((bridge->type != BRIDGE_TYPE_HOST) &&
+	    ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func)) {
+		status = acpi_install_notify_handler(bridge->func->handle,
+						ACPI_SYSTEM_NOTIFY,
+						handle_hotplug_event_func,
+						bridge->func);
+		if (ACPI_FAILURE(status))
+			err("failed to install interrupt notify handler\n");
+	}
+
 	slot = bridge->slots;
 	while (slot) {
 		struct acpiphp_slot *next = slot->next;
@@ -549,6 +627,11 @@ cleanup_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
 {
 	struct acpiphp_bridge *bridge;
 
+	/* cleanup p2p bridges under this P2P bridge
+	   in a depth-first manner */
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
+				cleanup_p2p_bridge, NULL, NULL);
+
 	if (!(bridge = acpiphp_handle_to_bridge(handle)))
 		return AE_OK;
 	cleanup_bridge(bridge);
@@ -559,15 +642,14 @@ static void remove_bridge(acpi_handle handle)
 {
 	struct acpiphp_bridge *bridge;
 
+	/* cleanup p2p bridges under this host bridge
+	   in a depth-first manner */
+	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
+				(u32)1, cleanup_p2p_bridge, NULL, NULL);
+
 	bridge = acpiphp_handle_to_bridge(handle);
-	if (bridge) {
+	if (bridge)
 		cleanup_bridge(bridge);
-	} else {
-		/* clean-up p2p bridges under this host bridge */
-		acpi_walk_namespace(ACPI_TYPE_DEVICE, handle,
-				    ACPI_UINT32_MAX, cleanup_p2p_bridge,
-				    NULL, NULL);
-	}
 }
 
 static struct pci_dev * get_apic_pci_info(acpi_handle handle)
@@ -881,6 +963,7 @@ static int enable_device(struct acpiphp_slot *slot)
 	struct acpiphp_func *func;
 	int retval = 0;
 	int num, max, pass;
+	acpi_status status;
 
 	if (slot->flags & SLOT_ENABLED)
 		goto err_exit;
@@ -933,6 +1016,17 @@ static int enable_device(struct acpiphp_slot *slot)
 		func = list_entry(l, struct acpiphp_func, sibling);
 		func->pci_dev = pci_get_slot(bus, PCI_DEVFN(slot->device,
 							func->function));
+		if (!func->pci_dev)
+			continue;
+
+		if (func->pci_dev->hdr_type != PCI_HEADER_TYPE_BRIDGE &&
+		    func->pci_dev->hdr_type != PCI_HEADER_TYPE_CARDBUS)
+			continue;
+
+		status = find_p2p_bridge(func->handle, (u32)1, bus, NULL);
+		if (ACPI_FAILURE(status))
+			warn("find_p2p_bridge failed (error code = 0x%x)\n",
+				status);
 	}
 
 	slot->flags |= SLOT_ENABLED;
@@ -958,6 +1052,13 @@ static int disable_device(struct acpiphp_slot *slot)
 	list_for_each (l, &slot->funcs) {
 		func = list_entry(l, struct acpiphp_func, sibling);
 
+		if (func->bridge) {
+			/* cleanup p2p bridges under this P2P bridge */
+			cleanup_p2p_bridge(func->bridge->handle,
+						(u32)1, NULL, NULL);
+			func->bridge = NULL;
+		}
+
 		acpiphp_bus_trim(func->handle);
 		/* try to remove anyway.
 		 * acpiphp_bus_add might have been failed */
@@ -1292,6 +1393,13 @@ static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, void *cont
 	case ACPI_NOTIFY_EJECT_REQUEST:
 		/* request device eject */
 		dbg("%s: Device eject notify on %s\n", __FUNCTION__, objname);
+		if ((bridge->type != BRIDGE_TYPE_HOST) &&
+		    (bridge->flags & BRIDGE_HAS_EJ0)) {
+			struct acpiphp_slot *slot;
+			slot = bridge->func->slot;
+			if (!acpiphp_disable_slot(slot))
+				acpiphp_eject_slot(slot);
+		}
 		break;
 
 	case ACPI_NOTIFY_FREQUENCY_MISMATCH: