PCI: acpiphp: Do not use ACPI PCI subdriver mechanism

Previously the acpiphp driver registered itself as an ACPI PCI subdriver,
so its callbacks were invoked when creating/destroying PCI root
buses to manage ACPI-based PCI hotplug slots.  But it doesn't handle
P2P bridge hotplug events, so it will cause strange behaviour if there
are hotplug slots associated with a hot-removed P2P bridge.

This patch fixes this issue by:
1) Directly hooking into PCI core to update hotplug slot devices when
   creating/destroying PCI buses through:
	pci_{add|remove}_bus() -> acpi_pci_{add|remove}_bus()
2) Getting rid of unused ACPI PCI subdriver-related code

It also cleans up unused code in the acpiphp driver.

[bhelgaas: keep acpi_pci_add_bus() stub for CONFIG_ACPI=n]
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Yinghai Lu <yinghai@kernel.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Toshi Kani <toshi.kani@hp.com>
This commit is contained in:
Jiang Liu 2013-04-12 05:44:26 +00:00 committed by Bjorn Helgaas
parent 6037a803b0
commit 3b63aaa70e
5 changed files with 71 additions and 247 deletions

View file

@ -119,7 +119,6 @@ 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 notifier_block nb;
@ -176,8 +175,6 @@ 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);
typedef int (*acpiphp_callback)(struct acpiphp_slot *slot, void *data);
extern int acpiphp_enable_slot (struct acpiphp_slot *slot);

View file

@ -37,6 +37,7 @@
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/pci_hotplug.h>
#include <linux/slab.h>
#include <linux/smp.h>
@ -354,19 +355,9 @@ void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
}
static int __init acpiphp_init(void)
void __init acpiphp_init(void)
{
info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
acpiphp_disabled ? ", disabled by user; please report a bug"
: "");
if (acpi_pci_disabled || acpiphp_disabled)
return 0;
/* read all the ACPI info from the system */
/* initialize internal data structure etc. */
return acpiphp_glue_init();
}
module_init(acpiphp_init);

View file

@ -157,6 +157,7 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
int device, function, retval;
struct pci_bus *pbus = bridge->pci_bus;
struct pci_dev *pdev;
u32 val;
if (!acpi_pci_check_ejectable(pbus, handle) && !is_dock_device(handle))
return AE_OK;
@ -249,11 +250,9 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv)
newfunc->slot = slot;
list_add_tail(&newfunc->sibling, &slot->funcs);
pdev = pci_get_slot(pbus, PCI_DEVFN(device, function));
if (pdev) {
if (pci_bus_read_dev_vendor_id(pbus, PCI_DEVFN(device, function),
&val, 60*1000))
slot->flags |= (SLOT_ENABLED | SLOT_POWEREDON);
pci_dev_put(pdev);
}
if (is_dock_device(handle)) {
/* we don't want to call this device's _EJ0
@ -366,148 +365,6 @@ static struct acpiphp_func *acpiphp_bridge_handle_to_function(acpi_handle handle
}
static inline void config_p2p_bridge_flags(struct acpiphp_bridge *bridge)
{
acpi_handle dummy_handle;
struct acpiphp_func *func;
if (ACPI_SUCCESS(acpi_get_handle(bridge->handle,
"_EJ0", &dummy_handle))) {
bridge->flags |= BRIDGE_HAS_EJ0;
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(struct acpi_pci_root *root)
{
struct acpiphp_bridge *bridge;
acpi_handle handle = root->device->handle;
bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
if (bridge == NULL)
return;
bridge->handle = handle;
bridge->pci_bus = root->bus;
init_bridge_misc(bridge);
}
/* allocate and initialize PCI-to-PCI bridge data structure */
static void add_p2p_bridge(acpi_handle *handle)
{
struct acpiphp_bridge *bridge;
bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
if (bridge == NULL) {
err("out of memory\n");
return;
}
bridge->handle = handle;
config_p2p_bridge_flags(bridge);
bridge->pci_dev = acpi_get_pci_dev(handle);
bridge->pci_bus = bridge->pci_dev->subordinate;
if (!bridge->pci_bus) {
err("This is not a PCI-to-PCI bridge!\n");
goto err;
}
/*
* Grab a ref to the subordinate PCI bus in case the bus is
* removed via PCI core logical hotplug. The ref pins the bus
* (which we access during module unload).
*/
get_device(&bridge->pci_bus->dev);
init_bridge_misc(bridge);
return;
err:
pci_dev_put(bridge->pci_dev);
kfree(bridge);
return;
}
/* callback routine to find P2P bridges */
static acpi_status
find_p2p_bridge(acpi_handle handle, u32 lvl, void *context, void **rv)
{
acpi_status status;
struct pci_dev *dev;
dev = acpi_get_pci_dev(handle);
if (!dev || !dev->subordinate)
goto out;
/* check if this bridge has ejectable slots */
if ((detect_ejectable_slots(handle) > 0)) {
dbg("found PCI-to-PCI bridge at PCI %s\n", pci_name(dev));
add_p2p_bridge(handle);
}
/* search P2P bridges under this p2p bridge */
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
find_p2p_bridge, NULL, NULL, NULL);
if (ACPI_FAILURE(status))
warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
out:
pci_dev_put(dev);
return AE_OK;
}
/* find hot-pluggable slots, and then find P2P bridge */
static int add_bridge(struct acpi_pci_root *root)
{
acpi_status status;
unsigned long long tmp;
acpi_handle dummy_handle;
acpi_handle handle = root->device->handle;
/* if the bridge doesn't have _STA, we assume it is always there */
status = acpi_get_handle(handle, "_STA", &dummy_handle);
if (ACPI_SUCCESS(status)) {
status = acpi_evaluate_integer(handle, "_STA", NULL, &tmp);
if (ACPI_FAILURE(status)) {
dbg("%s: _STA evaluation failure\n", __func__);
return 0;
}
if ((tmp & ACPI_STA_DEVICE_FUNCTIONING) == 0)
/* don't register this object */
return 0;
}
/* check if this bridge has ejectable slots */
if (detect_ejectable_slots(handle) > 0) {
dbg("found PCI host-bus bridge with hot-pluggable slots\n");
add_host_bridge(root);
}
/* search P2P bridges under this host bridge */
status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, (u32)1,
find_p2p_bridge, NULL, NULL, NULL);
if (ACPI_FAILURE(status))
warn("find_p2p_bridge failed (error code = 0x%x)\n", status);
return 0;
}
static struct acpiphp_bridge *acpiphp_handle_to_bridge(acpi_handle handle)
{
struct acpiphp_bridge *bridge;
@ -567,56 +424,12 @@ static void cleanup_bridge(struct acpiphp_bridge *bridge)
slot = next;
}
/*
* Only P2P bridges have a pci_dev
*/
if (bridge->pci_dev)
put_device(&bridge->pci_bus->dev);
put_device(&bridge->pci_bus->dev);
pci_dev_put(bridge->pci_dev);
list_del(&bridge->list);
kfree(bridge);
}
static acpi_status
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, NULL);
bridge = acpiphp_handle_to_bridge(handle);
if (bridge)
cleanup_bridge(bridge);
return AE_OK;
}
static void remove_bridge(struct acpi_pci_root *root)
{
struct acpiphp_bridge *bridge;
acpi_handle handle = root->device->handle;
/* 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, NULL);
/*
* On root bridges with hotplug slots directly underneath (ie,
* no p2p bridge between), we call cleanup_bridge().
*
* The else clause cleans up root bridges that either had no
* hotplug slots at all, or had a p2p bridge underneath.
*/
bridge = acpiphp_handle_to_bridge(handle);
if (bridge)
cleanup_bridge(bridge);
}
static int power_on_slot(struct acpiphp_slot *slot)
{
acpi_status status;
@ -798,6 +611,7 @@ static void check_hotplug_bridge(struct acpiphp_slot *slot, struct pci_dev *dev)
}
}
}
/**
* enable_device - enable, configure a slot
* @slot: slot to be enabled
@ -812,7 +626,6 @@ static int __ref 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;
@ -867,18 +680,6 @@ static int __ref enable_device(struct acpiphp_slot *slot)
slot->flags &= (~SLOT_ENABLED);
continue;
}
if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE &&
dev->hdr_type != PCI_HEADER_TYPE_CARDBUS) {
pci_dev_put(dev);
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);
pci_dev_put(dev);
}
@ -912,16 +713,6 @@ static int disable_device(struct acpiphp_slot *slot)
{
struct acpiphp_func *func;
struct pci_dev *pdev;
struct pci_bus *bus = slot->bridge->pci_bus;
list_for_each_entry(func, &slot->funcs, sibling) {
if (func->bridge) {
/* cleanup p2p bridges under this P2P bridge */
cleanup_p2p_bridge(func->bridge->handle,
(u32)1, NULL, NULL);
func->bridge = NULL;
}
}
/*
* enable_device() enumerates all functions in this device via
@ -940,7 +731,6 @@ static int disable_device(struct acpiphp_slot *slot)
slot->flags &= (~SLOT_ENABLED);
err_exit:
return 0;
}
@ -1287,30 +1077,62 @@ static void handle_hotplug_event_func(acpi_handle handle, u32 type,
alloc_acpi_hp_work(handle, type, context, _handle_hotplug_event_func);
}
static struct acpi_pci_driver acpi_pci_hp_driver = {
.add = add_bridge,
.remove = remove_bridge,
};
/**
* acpiphp_glue_init - initializes all PCI hotplug - ACPI glue data structures
/*
* Create hotplug slots for the PCI bus.
* It should always return 0 to avoid skipping following notifiers.
*/
int __init acpiphp_glue_init(void)
void acpiphp_enumerate_slots(struct pci_bus *bus, acpi_handle handle)
{
acpi_pci_register_driver(&acpi_pci_hp_driver);
acpi_handle dummy_handle;
struct acpiphp_bridge *bridge;
return 0;
if (acpiphp_disabled)
return;
if (detect_ejectable_slots(handle) <= 0)
return;
bridge = kzalloc(sizeof(struct acpiphp_bridge), GFP_KERNEL);
if (bridge == NULL) {
err("out of memory\n");
return;
}
bridge->handle = handle;
bridge->pci_dev = pci_dev_get(bus->self);
bridge->pci_bus = bus;
/*
* Grab a ref to the subordinate PCI bus in case the bus is
* removed via PCI core logical hotplug. The ref pins the bus
* (which we access during module unload).
*/
get_device(&bus->dev);
if (!pci_is_root_bus(bridge->pci_bus) &&
ACPI_SUCCESS(acpi_get_handle(bridge->handle,
"_EJ0", &dummy_handle))) {
dbg("found ejectable p2p bridge\n");
bridge->flags |= BRIDGE_HAS_EJ0;
bridge->func = acpiphp_bridge_handle_to_function(handle);
}
init_bridge_misc(bridge);
}
/**
* acpiphp_glue_exit - terminates all PCI hotplug - ACPI glue data structures
*
* This function frees all data allocated in acpiphp_glue_init().
*/
void acpiphp_glue_exit(void)
/* Destroy hotplug slots associated with the PCI bus */
void acpiphp_remove_slots(struct pci_bus *bus)
{
acpi_pci_unregister_driver(&acpi_pci_hp_driver);
struct acpiphp_bridge *bridge, *tmp;
if (acpiphp_disabled)
return;
list_for_each_entry_safe(bridge, tmp, &bridge_list, list)
if (bridge->pci_bus == bus) {
cleanup_bridge(bridge);
break;
}
}
/**

View file

@ -297,6 +297,7 @@ void acpi_pci_add_bus(struct pci_bus *bus)
return;
acpi_pci_slot_enumerate(bus, handle);
acpiphp_enumerate_slots(bus, handle);
}
void acpi_pci_remove_bus(struct pci_bus *bus)
@ -308,6 +309,7 @@ void acpi_pci_remove_bus(struct pci_bus *bus)
if (acpi_pci_disabled)
return;
acpiphp_remove_slots(bus);
acpi_pci_slot_remove(bus);
}
@ -388,6 +390,7 @@ static int __init acpi_pci_init(void)
pci_set_platform_pm(&acpi_pci_platform_pm);
acpi_pci_slot_init();
acpiphp_init();
return 0;
}

View file

@ -56,6 +56,17 @@ static inline void acpi_pci_slot_enumerate(struct pci_bus *bus,
static inline void acpi_pci_slot_remove(struct pci_bus *bus) { }
#endif
#ifdef CONFIG_HOTPLUG_PCI_ACPI
void acpiphp_init(void);
void acpiphp_enumerate_slots(struct pci_bus *bus, acpi_handle handle);
void acpiphp_remove_slots(struct pci_bus *bus);
#else
static inline void acpiphp_init(void) { }
static inline void acpiphp_enumerate_slots(struct pci_bus *bus,
acpi_handle handle) { }
static inline void acpiphp_remove_slots(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) { }