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Commit 5c0b04e3 authored by Jiang Liu's avatar Jiang Liu Committed by Bjorn Helgaas
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PCI/ACPI: Handle PCI slot devices when creating/destroying PCI buses 



Currently the pci_slot driver doesn't update PCI slot devices when PCI
device hotplug event happens, which may cause memory leak and returning
stale information to user.

Now the pci_slot driver has been changed as built-in driver, so invoke
PCI slot enumeration and destroy routines directly from the PCI core.
And remove ACPI PCI sub-driver related code because it isn't needed
any more.

[bhelgas: removed "extern" from function declarations]
Signed-off-by: default avatarJiang Liu <jiang.liu@huawei.com>
Signed-off-by: default avatarYijing Wang <wangyijing@huawei.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarYinghai Lu <yinghai@kernel.org>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
parent 89016506

drivers/acpi/pci_slot.c

+24 −146
Original line number Diff line number Diff line
@@ -9,6 +9,9 @@ 
 *  Copyright (C) 2007-2008 Hewlett-Packard Development Company, L.P.

 *  	Alex Chiang <achiang@hp.com>

 *

 *  Copyright (C) 2013 Huawei Tech. Co., Ltd.

 *	Jiang Liu <jiang.liu@huawei.com>

 *

 *  This program is free software; you can redistribute it and/or modify it

 *  under the terms and conditions of the GNU General Public License,

 *  version 2, as published by the Free Software Foundation.
@@ -28,10 +31,9 @@ 
#include <linux/init.h>

#include <linux/slab.h>

#include <linux/types.h>

#include <linux/list.h>

#include <linux/pci.h>

#include <linux/acpi.h>

#include <acpi/acpi_bus.h>

#include <acpi/acpi_drivers.h>

#include <linux/dmi.h>



static bool debug;
@@ -61,20 +63,12 @@ ACPI_MODULE_NAME("pci_slot"); 
#define SLOT_NAME_SIZE 21		/* Inspired by #define in acpiphp.h */



struct acpi_pci_slot {

	acpi_handle root_handle;	/* handle of the root bridge */

	struct pci_slot *pci_slot;	/* corresponding pci_slot */

	struct list_head list;		/* node in the list of slots */

};



static int acpi_pci_slot_add(struct acpi_pci_root *root);

static void acpi_pci_slot_remove(struct acpi_pci_root *root);



static LIST_HEAD(slot_list);

static DEFINE_MUTEX(slot_list_lock);

static struct acpi_pci_driver acpi_pci_slot_driver = {

	.add = acpi_pci_slot_add,

	.remove = acpi_pci_slot_remove,

};



static int

check_slot(acpi_handle handle, unsigned long long *sun)
@@ -113,21 +107,8 @@ out: 
	return device;

}



struct callback_args {

	acpi_walk_callback	user_function;	/* only for walk_p2p_bridge */

	struct pci_bus		*pci_bus;

	acpi_handle		root_handle;

};



/*

 * 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.

 * Check whether handle has an associated slot and create PCI slot if it has.

 */

static acpi_status

register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
@@ -137,13 +118,22 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) 
	char name[SLOT_NAME_SIZE];

	struct acpi_pci_slot *slot;

	struct pci_slot *pci_slot;

	struct callback_args *parent_context = context;

	struct pci_bus *pci_bus = parent_context->pci_bus;

	struct pci_bus *pci_bus = context;



	device = check_slot(handle, &sun);

	if (device < 0)

		return AE_OK;



	/*

	 * There may be multiple PCI functions associated with the same slot.

	 * Check whether PCI slot has already been created for this PCI device.

	 */

	list_for_each_entry(slot, &slot_list, list) {

		pci_slot = slot->pci_slot;

		if (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__);
@@ -158,12 +148,8 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) 
		return AE_OK;

	}



	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);
@@ -173,131 +159,24 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) 
	return AE_OK;

}



/*

 * walk_p2p_bridge - discover and walk p2p bridges

 * @handle: points to an acpi_pci_root

 * @context: p2p_bridge_context pointer

 *

 * Note that when we call ourselves recursively, we pass a different

 * value of pci_bus in the child_context.

 */

static acpi_status

walk_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)

void acpi_pci_slot_enumerate(struct pci_bus *bus, acpi_handle handle)

{

	int device, function;

	unsigned long long adr;

	acpi_status status;

	acpi_handle dummy_handle;

	acpi_walk_callback user_function;



	struct pci_dev *dev;

	struct pci_bus *pci_bus;

	struct callback_args child_context;

	struct callback_args *parent_context = context;



	pci_bus = parent_context->pci_bus;

	user_function = parent_context->user_function;



	status = acpi_get_handle(handle, "_ADR", &dummy_handle);

	if (ACPI_FAILURE(status))

		return AE_OK;



	status = acpi_evaluate_integer(handle, "_ADR", NULL, &adr);

	if (ACPI_FAILURE(status))

		return AE_OK;



	device = (adr >> 16) & 0xffff;

	function = adr & 0xffff;



	dev = pci_get_slot(pci_bus, PCI_DEVFN(device, function));

	if (!dev || !dev->subordinate)

		goto out;



	child_context.pci_bus = dev->subordinate;

	child_context.user_function = user_function;

	child_context.root_handle = parent_context->root_handle;



	dbg("p2p bridge walk, pci_bus = %x\n", dev->subordinate->number);

	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,

				     user_function, NULL, &child_context, NULL);

	if (ACPI_FAILURE(status))

		goto out;



	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,

				     walk_p2p_bridge, NULL, &child_context, NULL);

out:

	pci_dev_put(dev);

	return AE_OK;

}



/*

 * walk_root_bridge - generic root bridge walker

 * @root: poiner of an acpi_pci_root

 * @user_function: user callback for slot objects

 *

 * Call user_function for all objects underneath this root bridge.

 * Walk p2p bridges underneath us and call user_function on those too.

 */

static int

walk_root_bridge(struct acpi_pci_root *root, acpi_walk_callback user_function)

{

	acpi_status status;

	acpi_handle handle = root->device->handle;

	struct pci_bus *pci_bus = root->bus;

	struct callback_args context;



	context.pci_bus = pci_bus;

	context.user_function = user_function;

	context.root_handle = handle;



	dbg("root bridge walk, pci_bus = %x\n", pci_bus->number);

	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,

				     user_function, NULL, &context, NULL);

	if (ACPI_FAILURE(status))

		return status;



	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,

				     walk_p2p_bridge, NULL, &context, NULL);

	if (ACPI_FAILURE(status))

		err("%s: walk_p2p_bridge failure - %d\n", __func__, status);



	return status;

}



/*

 * acpi_pci_slot_add

 * @handle: points to an acpi_pci_root

 */

static int

acpi_pci_slot_add(struct acpi_pci_root *root)

{

	acpi_status status;



	status = walk_root_bridge(root, register_slot);

	if (ACPI_FAILURE(status))

		err("%s: register_slot failure - %d\n", __func__, status);



	return status;

	mutex_lock(&slot_list_lock);

	acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,

			    register_slot, NULL, bus, NULL);

	mutex_unlock(&slot_list_lock);

}



/*

 * acpi_pci_slot_remove

 * @handle: points to an acpi_pci_root

 */

static void

acpi_pci_slot_remove(struct acpi_pci_root *root)

void acpi_pci_slot_remove(struct pci_bus *bus)

{

	struct acpi_pci_slot *slot, *tmp;

	struct pci_bus *pbus;

	acpi_handle handle = root->device->handle;



	mutex_lock(&slot_list_lock);

	list_for_each_entry_safe(slot, tmp, &slot_list, list) {

		if (slot->root_handle == handle) {

		if (slot->pci_slot->bus == bus) {

			list_del(&slot->list);

			pbus = slot->pci_slot->bus;

			pci_destroy_slot(slot->pci_slot);

			put_device(&pbus->dev);

			put_device(&bus->dev);

			kfree(slot);

		}

	}
@@ -332,5 +211,4 @@ static struct dmi_system_id acpi_pci_slot_dmi_table[] __initdata = { 
void __init acpi_pci_slot_init(void)

{

	dmi_check_system(acpi_pci_slot_dmi_table);

	acpi_pci_register_driver(&acpi_pci_slot_driver);

}

drivers/acpi/scan.c

+0 −1
Original line number Diff line number Diff line
@@ -1790,7 +1790,6 @@ int __init acpi_scan_init(void) 
	acpi_platform_init();

	acpi_csrt_init();

	acpi_container_init();

	acpi_pci_slot_init();



	mutex_lock(&acpi_scan_lock);

	/*

drivers/pci/pci-acpi.c

+5 −2
Original line number Diff line number Diff line
@@ -296,7 +296,7 @@ void acpi_pci_add_bus(struct pci_bus *bus) 
	if (acpi_pci_disabled || handle == NULL)

		return;



	/* TODO: add PCI slots and acpiphp hotplug slots */

	acpi_pci_slot_enumerate(bus, handle);

}



void acpi_pci_remove_bus(struct pci_bus *bus)
@@ -308,7 +308,7 @@ void acpi_pci_remove_bus(struct pci_bus *bus) 
	if (acpi_pci_disabled)

		return;



	/* TODO: remove PCI slots and acpiphp hotplug slots */

	acpi_pci_slot_remove(bus);

}



/* ACPI bus type */
@@ -385,7 +385,10 @@ static int __init acpi_pci_init(void) 
	ret = register_acpi_bus_type(&acpi_pci_bus);

	if (ret)

		return 0;



	pci_set_platform_pm(&acpi_pci_platform_pm);

	acpi_pci_slot_init();



	return 0;

}

arch_initcall(acpi_pci_init);

include/linux/pci-acpi.h

+12 −0
Original line number Diff line number Diff line
@@ -44,6 +44,18 @@ static inline acpi_handle acpi_pci_get_bridge_handle(struct pci_bus *pbus) 


void acpi_pci_add_bus(struct pci_bus *bus);

void acpi_pci_remove_bus(struct pci_bus *bus);



#ifdef	CONFIG_ACPI_PCI_SLOT

void acpi_pci_slot_init(void);

void acpi_pci_slot_enumerate(struct pci_bus *bus, acpi_handle handle);

void acpi_pci_slot_remove(struct pci_bus *bus);

#else

static inline void acpi_pci_slot_init(void) { }

static inline void acpi_pci_slot_enumerate(struct pci_bus *bus,

					   acpi_handle handle) { }

static inline void acpi_pci_slot_remove(struct pci_bus *bus) { }

#endif



#else	/* CONFIG_ACPI */

static inline void acpi_pci_add_bus(struct pci_bus *bus) { }

static inline void acpi_pci_remove_bus(struct pci_bus *bus) { }