[PATCH] acpiphp - slot management fix - V4

o This patch removes IDs (for slots management).
o This patch removes the slot register/unregister processes
from the init/exit phases. Instead, adds these processes
in the bridge add/cleanup phases.
o Currently, this change doesn't have any meanings. But
these changes are needed to support p2p bridge(with
hotplug slot)

Signed-off-by: MUNEDA Takahiro <[e-mail]>
Signed-off-by: Kristen Carlson Accardi <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/pci/hotplug/acpiphp.h

···
  * struct slot - slot information for each *physical* slot
  */
 struct slot {
-	u8 number;
 	struct hotplug_slot	*hotplug_slot;
-	struct list_head	slot_list;
-
 	struct acpiphp_slot	*acpi_slot;
 };
 
···
 	struct acpiphp_bridge *bridge;	/* parent */
 	struct list_head funcs;		/* one slot may have different
 					   objects (i.e. for each function) */
+	struct slot *slot;
 	struct mutex crit_sect;
 
-	u32		id;		/* slot id (serial #) for hotplug core */
 	u8		device;		/* pci device# */
 
 	u32		sun;		/* ACPI _SUN (slot unique number) */
···
 /* acpiphp_core.c */
 extern int acpiphp_register_attention(struct acpiphp_attention_info*info);
 extern int acpiphp_unregister_attention(struct acpiphp_attention_info *info);
+extern int acpiphp_register_hotplug_slot(struct acpiphp_slot *slot);
+extern void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *slot);
 
 /* acpiphp_glue.c */
 extern int acpiphp_glue_init (void);
 extern void acpiphp_glue_exit (void);
 extern int acpiphp_get_num_slots (void);
-extern struct acpiphp_slot *get_slot_from_id (int id);
 typedef int (*acpiphp_callback)(struct acpiphp_slot *slot, void *data);
 void handle_hotplug_event_func(acpi_handle, u32, void*);
 

drivers/pci/hotplug/acpiphp_core.c

···
 #include "pci_hotplug.h"
 #include "acpiphp.h"
 
-static LIST_HEAD(slot_list);
-
 #define MY_NAME	"acpiphp"
 
 static int debug;
···
 	kfree(slot);
 }
 
-/**
- * init_slots - initialize 'struct slot' structures for each slot
- *
- */
-static int __init init_slots(void)
+/* callback routine to initialize 'struct slot' for each slot */
+int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
 {
 	struct slot *slot;
+	struct hotplug_slot *hotplug_slot;
+	struct hotplug_slot_info *hotplug_slot_info;
 	int retval = -ENOMEM;
-	int i;
 
-	for (i = 0; i < num_slots; ++i) {
-		slot = kmalloc(sizeof(struct slot), GFP_KERNEL);
-		if (!slot)
-			goto error;
-		memset(slot, 0, sizeof(struct slot));
+	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
+	if (!slot)
+		goto error;
 
-		slot->hotplug_slot = kmalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
-		if (!slot->hotplug_slot)
-			goto error_slot;
-		memset(slot->hotplug_slot, 0, sizeof(struct hotplug_slot));
+	slot->hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
+	if (!slot->hotplug_slot)
+		goto error_slot;
 
-		slot->hotplug_slot->info = kmalloc(sizeof(struct hotplug_slot_info), GFP_KERNEL);
-		if (!slot->hotplug_slot->info)
-			goto error_hpslot;
-		memset(slot->hotplug_slot->info, 0, sizeof(struct hotplug_slot_info));
+	slot->hotplug_slot->info = kzalloc(sizeof(*hotplug_slot_info),
+					   GFP_KERNEL);
+	if (!slot->hotplug_slot->info)
+		goto error_hpslot;
 
-		slot->hotplug_slot->name = kmalloc(SLOT_NAME_SIZE, GFP_KERNEL);
-		if (!slot->hotplug_slot->name)
-			goto error_info;
+	slot->hotplug_slot->name = kzalloc(SLOT_NAME_SIZE, GFP_KERNEL);
+	if (!slot->hotplug_slot->name)
+		goto error_info;
 
-		slot->number = i;
+	slot->hotplug_slot->private = slot;
+	slot->hotplug_slot->release = &release_slot;
+	slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
 
-		slot->hotplug_slot->private = slot;
-		slot->hotplug_slot->release = &release_slot;
-		slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
+	slot->acpi_slot = acpiphp_slot;
+	slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
+	slot->hotplug_slot->info->attention_status = 0;
+	slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
+	slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
+	slot->hotplug_slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
+	slot->hotplug_slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
 
-		slot->acpi_slot = get_slot_from_id(i);
-		slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
-		slot->hotplug_slot->info->attention_status = 0;
-		slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
-		slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
-		slot->hotplug_slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
-		slot->hotplug_slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
+	acpiphp_slot->slot = slot;
+	make_slot_name(slot);
 
-		make_slot_name(slot);
+	retval = pci_hp_register(slot->hotplug_slot);
+	if (retval) {
+		err("pci_hp_register failed with error %d\n", retval);
+		goto error_name;
+ 	}
 
-		retval = pci_hp_register(slot->hotplug_slot);
-		if (retval) {
-			err("pci_hp_register failed with error %d\n", retval);
-			goto error_name;
-		}
-
-		/* add slot to our internal list */
-		list_add(&slot->slot_list, &slot_list);
-		info("Slot [%s] registered\n", slot->hotplug_slot->name);
-	}
+	info("Slot [%s] registered\n", slot->hotplug_slot->name);
 
 	return 0;
 error_name:
···
 }
 
 
-static void __exit cleanup_slots (void)
+void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
 {
-	struct list_head *tmp, *n;
-	struct slot *slot;
+	struct slot *slot = acpiphp_slot->slot;
+	int retval = 0;
 
-	list_for_each_safe (tmp, n, &slot_list) {
-		/* memory will be freed in release_slot callback */
-		slot = list_entry(tmp, struct slot, slot_list);
-		list_del(&slot->slot_list);
-		pci_hp_deregister(slot->hotplug_slot);
-	}
+	info ("Slot [%s] unregistered\n", slot->hotplug_slot->name);
+
+	retval = pci_hp_deregister(slot->hotplug_slot);
+	if (retval)
+		err("pci_hp_deregister failed with error %d\n", retval);
 }
 
 
···
 
 	/* read all the ACPI info from the system */
 	retval = init_acpi();
-	if (retval && !(docking_station))
-		return retval;
 
-	return init_slots();
+	/* if we have found a docking station, we should
+	 * go ahead and load even if init_acpi has found
+	 * no slots.  This handles the case when the _DCK
+	 * method not defined under the actual dock bridge
+	 */
+	if (docking_station)
+		return 0;
+	else
+		return retval;
 }
 
 
 static void __exit acpiphp_exit(void)
 {
-	cleanup_slots();
 	/* deallocate internal data structures etc. */
 	acpiphp_glue_exit();
 

drivers/pci/hotplug/acpiphp_glue.c

···
 	acpi_handle tmp;
 	acpi_status status = AE_OK;
 	unsigned long adr, sun;
-	int device, function;
-	static int num_slots = 0;	/* XXX if we support I/O node hotplug... */
+	int device, function, retval;
 
 	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);
 
···
 
 		memset(slot, 0, sizeof(struct acpiphp_slot));
 		slot->bridge = bridge;
-		slot->id = num_slots++;
 		slot->device = device;
 		slot->sun = sun;
 		INIT_LIST_HEAD(&slot->funcs);
···
 		dbg("found ACPI PCI Hotplug slot %d at PCI %04x:%02x:%02x\n",
 				slot->sun, pci_domain_nr(bridge->pci_bus),
 				bridge->pci_bus->number, slot->device);
+		retval = acpiphp_register_hotplug_slot(slot);
+		if (retval) {
+			warn("acpiphp_register_hotplug_slot failed(err code = 0x%x)\n", retval);
+			goto err_exit;
+		}
 	}
 
 	newfunc->slot = slot;
···
 		status = AE_OK;
 
 	return status;
+
+ err_exit:
+	bridge->nr_slots--;
+	bridge->slots = slot->next;
+	kfree(slot);
+	kfree(newfunc);
+
+	return AE_OK;
 }
 
 
···
 	/* decode ACPI 2.0 _HPP (hot plug parameters) */
 	decode_hpp(bridge);
 
+	/* must be added to the list prior to calling register_slot */
+	list_add(&bridge->list, &bridge_list);
+
 	/* register all slot objects under this bridge */
 	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, bridge->handle, (u32)1,
 				     register_slot, bridge, NULL);
+	if (ACPI_FAILURE(status)) {
+		list_del(&bridge->list);
+		return;
+	}
 
 	/* install notify handler */
 	if (bridge->type != BRIDGE_TYPE_HOST) {
···
 			err("failed to register interrupt notify handler\n");
 		}
 	}
-
-	list_add(&bridge->list, &bridge_list);
 }
 
 
···
 			list_del(list);
 			kfree(func);
 		}
+		acpiphp_unregister_hotplug_slot(slot);
+		list_del(&slot->funcs);
 		kfree(slot);
 		slot = next;
 	}
···
 	return retval;
 }
 #endif
-
-/* search matching slot from id  */
-struct acpiphp_slot *get_slot_from_id(int id)
-{
-	struct list_head *node;
-	struct acpiphp_bridge *bridge;
-	struct acpiphp_slot *slot;
-
-	list_for_each (node, &bridge_list) {
-		bridge = (struct acpiphp_bridge *)node;
-		for (slot = bridge->slots; slot; slot = slot->next)
-			if (slot->id == id)
-				return slot;
-	}
-
-	/* should never happen! */
-	err("%s: no object for id %d\n", __FUNCTION__, id);
-	WARN_ON(1);
-	return NULL;
-}
 
 
 /**