mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Lukas Wunner](/assets/img/avatar_default.png)
When a hotplug driver calls pci_hp_register(), all steps necessary for registration are carried out in one go, including creation of a kobject and addition to sysfs. That's a problem for pciehp once it's converted to enable/disable the slot exclusively from the IRQ thread: The thread needs to be spawned after creation of the kobject (because it uses the kobject's name), but before addition to sysfs (because it will handle enable/disable requests submitted via sysfs). pci_hp_deregister() does offer a ->release callback that's invoked after deletion from sysfs and before destruction of the kobject. But because pci_hp_register() doesn't offer a counterpart, hotplug drivers' ->probe and ->remove code becomes asymmetric, which is error prone as recently discovered use-after-free bugs in pciehp's ->remove hook have shown. In a sense, this appears to be a case of the midlayer antipattern: "The core thesis of the "midlayer mistake" is that midlayers are bad and should not exist. That common functionality which it is so tempting to put in a midlayer should instead be provided as library routines which can [be] used, augmented, or ignored by each bottom level driver independently. Thus every subsystem that supports multiple implementations (or drivers) should provide a very thin top layer which calls directly into the bottom layer drivers, and a rich library of support code that eases the implementation of those drivers. This library is available to, but not forced upon, those drivers." -- Neil Brown (2009), https://lwn.net/Articles/336262/ The presence of midlayer traits in the PCI hotplug core might be ascribed to its age: When it was introduced in February 2002, the blessings of a library approach might not have been well known: https://git.kernel.org/tglx/history/c/a8a2069f432c For comparison, the driver core does offer split functions for creating a kobject (device_initialize()) and addition to sysfs (device_add()) as an alternative to carrying out everything at once (device_register()). This was introduced in October 2002: https://git.kernel.org/tglx/history/c/8b290eb19962 The odd ->release callback in the PCI hotplug core was added in 2003: https://git.kernel.org/tglx/history/c/69f8d663b595 Clearly, a library approach would not force every hotplug driver to implement a ->release callback, but rather allow the driver to remove the sysfs files, release its data structures and finally destroy the kobject. Alternatively, a driver may choose to remove everything with pci_hp_deregister(), then release its data structures. To this end, offer drivers pci_hp_initialize() and pci_hp_add() as a split-up version of pci_hp_register(). Likewise, offer pci_hp_del() and pci_hp_destroy() as a split-up version of pci_hp_deregister(). Eliminate the ->release callback and move its code into each driver's teardown routine. Declare pci_hp_deregister() void, in keeping with the usual kernel pattern that enablement can fail, but disablement cannot. It only returned an error if the caller passed in a NULL pointer or a slot which has never or is no longer registered or is sharing its name with another slot. Those would be bugs, so WARN about them. Few hotplug drivers actually checked the return value and those that did only printed a useless error message to dmesg. Remove that. For most drivers the conversion was straightforward since it doesn't matter whether the code in the ->release callback is executed before or after destruction of the kobject. But in the case of ibmphp, it was unclear to me whether setting slot_cur->ctrl and slot_cur->bus_on to NULL needs to happen before the kobject is destroyed, so I erred on the side of caution and ensured that the order stays the same. Another nontrivial case is pnv_php, I've found the list and kref logic difficult to understand, however my impression was that it is safe to delete the list element and drop the references until after the kobject is destroyed. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86 Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Scott Murray <scott@spiteful.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Gavin Shan <gwshan@linux.vnet.ibm.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Corentin Chary <corentin.chary@gmail.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Andy Shevchenko <andy@infradead.org>
603 lines
15 KiB
C
603 lines
15 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* PCI HotPlug Controller Core
|
|
*
|
|
* Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com)
|
|
* Copyright (C) 2001-2002 IBM Corp.
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* Send feedback to <kristen.c.accardi@intel.com>
|
|
*
|
|
* Authors:
|
|
* Greg Kroah-Hartman <greg@kroah.com>
|
|
* Scott Murray <scottm@somanetworks.com>
|
|
*/
|
|
|
|
#include <linux/module.h> /* try_module_get & module_put */
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/types.h>
|
|
#include <linux/list.h>
|
|
#include <linux/kobject.h>
|
|
#include <linux/sysfs.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/init.h>
|
|
#include <linux/mount.h>
|
|
#include <linux/namei.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/pci_hotplug.h>
|
|
#include <linux/uaccess.h>
|
|
#include "../pci.h"
|
|
#include "cpci_hotplug.h"
|
|
|
|
#define MY_NAME "pci_hotplug"
|
|
|
|
#define dbg(fmt, arg...) do { if (debug) printk(KERN_DEBUG "%s: %s: " fmt, MY_NAME, __func__, ## arg); } while (0)
|
|
#define err(format, arg...) printk(KERN_ERR "%s: " format, MY_NAME, ## arg)
|
|
#define info(format, arg...) printk(KERN_INFO "%s: " format, MY_NAME, ## arg)
|
|
#define warn(format, arg...) printk(KERN_WARNING "%s: " format, MY_NAME, ## arg)
|
|
|
|
/* local variables */
|
|
static bool debug;
|
|
|
|
static LIST_HEAD(pci_hotplug_slot_list);
|
|
static DEFINE_MUTEX(pci_hp_mutex);
|
|
|
|
/* Weee, fun with macros... */
|
|
#define GET_STATUS(name, type) \
|
|
static int get_##name(struct hotplug_slot *slot, type *value) \
|
|
{ \
|
|
struct hotplug_slot_ops *ops = slot->ops; \
|
|
int retval = 0; \
|
|
if (!try_module_get(ops->owner)) \
|
|
return -ENODEV; \
|
|
if (ops->get_##name) \
|
|
retval = ops->get_##name(slot, value); \
|
|
else \
|
|
*value = slot->info->name; \
|
|
module_put(ops->owner); \
|
|
return retval; \
|
|
}
|
|
|
|
GET_STATUS(power_status, u8)
|
|
GET_STATUS(attention_status, u8)
|
|
GET_STATUS(latch_status, u8)
|
|
GET_STATUS(adapter_status, u8)
|
|
|
|
static ssize_t power_read_file(struct pci_slot *pci_slot, char *buf)
|
|
{
|
|
int retval;
|
|
u8 value;
|
|
|
|
retval = get_power_status(pci_slot->hotplug, &value);
|
|
if (retval)
|
|
return retval;
|
|
|
|
return sprintf(buf, "%d\n", value);
|
|
}
|
|
|
|
static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf,
|
|
size_t count)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
unsigned long lpower;
|
|
u8 power;
|
|
int retval = 0;
|
|
|
|
lpower = simple_strtoul(buf, NULL, 10);
|
|
power = (u8)(lpower & 0xff);
|
|
dbg("power = %d\n", power);
|
|
|
|
if (!try_module_get(slot->ops->owner)) {
|
|
retval = -ENODEV;
|
|
goto exit;
|
|
}
|
|
switch (power) {
|
|
case 0:
|
|
if (slot->ops->disable_slot)
|
|
retval = slot->ops->disable_slot(slot);
|
|
break;
|
|
|
|
case 1:
|
|
if (slot->ops->enable_slot)
|
|
retval = slot->ops->enable_slot(slot);
|
|
break;
|
|
|
|
default:
|
|
err("Illegal value specified for power\n");
|
|
retval = -EINVAL;
|
|
}
|
|
module_put(slot->ops->owner);
|
|
|
|
exit:
|
|
if (retval)
|
|
return retval;
|
|
return count;
|
|
}
|
|
|
|
static struct pci_slot_attribute hotplug_slot_attr_power = {
|
|
.attr = {.name = "power", .mode = S_IFREG | S_IRUGO | S_IWUSR},
|
|
.show = power_read_file,
|
|
.store = power_write_file
|
|
};
|
|
|
|
static ssize_t attention_read_file(struct pci_slot *pci_slot, char *buf)
|
|
{
|
|
int retval;
|
|
u8 value;
|
|
|
|
retval = get_attention_status(pci_slot->hotplug, &value);
|
|
if (retval)
|
|
return retval;
|
|
|
|
return sprintf(buf, "%d\n", value);
|
|
}
|
|
|
|
static ssize_t attention_write_file(struct pci_slot *pci_slot, const char *buf,
|
|
size_t count)
|
|
{
|
|
struct hotplug_slot_ops *ops = pci_slot->hotplug->ops;
|
|
unsigned long lattention;
|
|
u8 attention;
|
|
int retval = 0;
|
|
|
|
lattention = simple_strtoul(buf, NULL, 10);
|
|
attention = (u8)(lattention & 0xff);
|
|
dbg(" - attention = %d\n", attention);
|
|
|
|
if (!try_module_get(ops->owner)) {
|
|
retval = -ENODEV;
|
|
goto exit;
|
|
}
|
|
if (ops->set_attention_status)
|
|
retval = ops->set_attention_status(pci_slot->hotplug, attention);
|
|
module_put(ops->owner);
|
|
|
|
exit:
|
|
if (retval)
|
|
return retval;
|
|
return count;
|
|
}
|
|
|
|
static struct pci_slot_attribute hotplug_slot_attr_attention = {
|
|
.attr = {.name = "attention", .mode = S_IFREG | S_IRUGO | S_IWUSR},
|
|
.show = attention_read_file,
|
|
.store = attention_write_file
|
|
};
|
|
|
|
static ssize_t latch_read_file(struct pci_slot *pci_slot, char *buf)
|
|
{
|
|
int retval;
|
|
u8 value;
|
|
|
|
retval = get_latch_status(pci_slot->hotplug, &value);
|
|
if (retval)
|
|
return retval;
|
|
|
|
return sprintf(buf, "%d\n", value);
|
|
}
|
|
|
|
static struct pci_slot_attribute hotplug_slot_attr_latch = {
|
|
.attr = {.name = "latch", .mode = S_IFREG | S_IRUGO},
|
|
.show = latch_read_file,
|
|
};
|
|
|
|
static ssize_t presence_read_file(struct pci_slot *pci_slot, char *buf)
|
|
{
|
|
int retval;
|
|
u8 value;
|
|
|
|
retval = get_adapter_status(pci_slot->hotplug, &value);
|
|
if (retval)
|
|
return retval;
|
|
|
|
return sprintf(buf, "%d\n", value);
|
|
}
|
|
|
|
static struct pci_slot_attribute hotplug_slot_attr_presence = {
|
|
.attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO},
|
|
.show = presence_read_file,
|
|
};
|
|
|
|
static ssize_t test_write_file(struct pci_slot *pci_slot, const char *buf,
|
|
size_t count)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
unsigned long ltest;
|
|
u32 test;
|
|
int retval = 0;
|
|
|
|
ltest = simple_strtoul(buf, NULL, 10);
|
|
test = (u32)(ltest & 0xffffffff);
|
|
dbg("test = %d\n", test);
|
|
|
|
if (!try_module_get(slot->ops->owner)) {
|
|
retval = -ENODEV;
|
|
goto exit;
|
|
}
|
|
if (slot->ops->hardware_test)
|
|
retval = slot->ops->hardware_test(slot, test);
|
|
module_put(slot->ops->owner);
|
|
|
|
exit:
|
|
if (retval)
|
|
return retval;
|
|
return count;
|
|
}
|
|
|
|
static struct pci_slot_attribute hotplug_slot_attr_test = {
|
|
.attr = {.name = "test", .mode = S_IFREG | S_IRUGO | S_IWUSR},
|
|
.store = test_write_file
|
|
};
|
|
|
|
static bool has_power_file(struct pci_slot *pci_slot)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
|
|
if ((!slot) || (!slot->ops))
|
|
return false;
|
|
if ((slot->ops->enable_slot) ||
|
|
(slot->ops->disable_slot) ||
|
|
(slot->ops->get_power_status))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static bool has_attention_file(struct pci_slot *pci_slot)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
|
|
if ((!slot) || (!slot->ops))
|
|
return false;
|
|
if ((slot->ops->set_attention_status) ||
|
|
(slot->ops->get_attention_status))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static bool has_latch_file(struct pci_slot *pci_slot)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
|
|
if ((!slot) || (!slot->ops))
|
|
return false;
|
|
if (slot->ops->get_latch_status)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static bool has_adapter_file(struct pci_slot *pci_slot)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
|
|
if ((!slot) || (!slot->ops))
|
|
return false;
|
|
if (slot->ops->get_adapter_status)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static bool has_test_file(struct pci_slot *pci_slot)
|
|
{
|
|
struct hotplug_slot *slot = pci_slot->hotplug;
|
|
|
|
if ((!slot) || (!slot->ops))
|
|
return false;
|
|
if (slot->ops->hardware_test)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static int fs_add_slot(struct pci_slot *pci_slot)
|
|
{
|
|
int retval = 0;
|
|
|
|
/* Create symbolic link to the hotplug driver module */
|
|
pci_hp_create_module_link(pci_slot);
|
|
|
|
if (has_power_file(pci_slot)) {
|
|
retval = sysfs_create_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_power.attr);
|
|
if (retval)
|
|
goto exit_power;
|
|
}
|
|
|
|
if (has_attention_file(pci_slot)) {
|
|
retval = sysfs_create_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_attention.attr);
|
|
if (retval)
|
|
goto exit_attention;
|
|
}
|
|
|
|
if (has_latch_file(pci_slot)) {
|
|
retval = sysfs_create_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_latch.attr);
|
|
if (retval)
|
|
goto exit_latch;
|
|
}
|
|
|
|
if (has_adapter_file(pci_slot)) {
|
|
retval = sysfs_create_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_presence.attr);
|
|
if (retval)
|
|
goto exit_adapter;
|
|
}
|
|
|
|
if (has_test_file(pci_slot)) {
|
|
retval = sysfs_create_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_test.attr);
|
|
if (retval)
|
|
goto exit_test;
|
|
}
|
|
|
|
goto exit;
|
|
|
|
exit_test:
|
|
if (has_adapter_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_presence.attr);
|
|
exit_adapter:
|
|
if (has_latch_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_latch.attr);
|
|
exit_latch:
|
|
if (has_attention_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_attention.attr);
|
|
exit_attention:
|
|
if (has_power_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_power.attr);
|
|
exit_power:
|
|
pci_hp_remove_module_link(pci_slot);
|
|
exit:
|
|
return retval;
|
|
}
|
|
|
|
static void fs_remove_slot(struct pci_slot *pci_slot)
|
|
{
|
|
if (has_power_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_power.attr);
|
|
|
|
if (has_attention_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_attention.attr);
|
|
|
|
if (has_latch_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_latch.attr);
|
|
|
|
if (has_adapter_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj,
|
|
&hotplug_slot_attr_presence.attr);
|
|
|
|
if (has_test_file(pci_slot))
|
|
sysfs_remove_file(&pci_slot->kobj, &hotplug_slot_attr_test.attr);
|
|
|
|
pci_hp_remove_module_link(pci_slot);
|
|
}
|
|
|
|
static struct hotplug_slot *get_slot_from_name(const char *name)
|
|
{
|
|
struct hotplug_slot *slot;
|
|
|
|
list_for_each_entry(slot, &pci_hotplug_slot_list, slot_list) {
|
|
if (strcmp(hotplug_slot_name(slot), name) == 0)
|
|
return slot;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* __pci_hp_register - register a hotplug_slot with the PCI hotplug subsystem
|
|
* @bus: bus this slot is on
|
|
* @slot: pointer to the &struct hotplug_slot to register
|
|
* @devnr: device number
|
|
* @name: name registered with kobject core
|
|
* @owner: caller module owner
|
|
* @mod_name: caller module name
|
|
*
|
|
* Prepares a hotplug slot for in-kernel use and immediately publishes it to
|
|
* user space in one go. Drivers may alternatively carry out the two steps
|
|
* separately by invoking pci_hp_initialize() and pci_hp_add().
|
|
*
|
|
* Returns 0 if successful, anything else for an error.
|
|
*/
|
|
int __pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus,
|
|
int devnr, const char *name,
|
|
struct module *owner, const char *mod_name)
|
|
{
|
|
int result;
|
|
|
|
result = __pci_hp_initialize(slot, bus, devnr, name, owner, mod_name);
|
|
if (result)
|
|
return result;
|
|
|
|
result = pci_hp_add(slot);
|
|
if (result)
|
|
pci_hp_destroy(slot);
|
|
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__pci_hp_register);
|
|
|
|
/**
|
|
* __pci_hp_initialize - prepare hotplug slot for in-kernel use
|
|
* @slot: pointer to the &struct hotplug_slot to initialize
|
|
* @bus: bus this slot is on
|
|
* @devnr: slot number
|
|
* @name: name registered with kobject core
|
|
* @owner: caller module owner
|
|
* @mod_name: caller module name
|
|
*
|
|
* Allocate and fill in a PCI slot for use by a hotplug driver. Once this has
|
|
* been called, the driver may invoke hotplug_slot_name() to get the slot's
|
|
* unique name. The driver must be prepared to handle a ->reset_slot callback
|
|
* from this point on.
|
|
*
|
|
* Returns 0 on success or a negative int on error.
|
|
*/
|
|
int __pci_hp_initialize(struct hotplug_slot *slot, struct pci_bus *bus,
|
|
int devnr, const char *name, struct module *owner,
|
|
const char *mod_name)
|
|
{
|
|
struct pci_slot *pci_slot;
|
|
|
|
if (slot == NULL)
|
|
return -ENODEV;
|
|
if ((slot->info == NULL) || (slot->ops == NULL))
|
|
return -EINVAL;
|
|
|
|
slot->ops->owner = owner;
|
|
slot->ops->mod_name = mod_name;
|
|
|
|
/*
|
|
* No problems if we call this interface from both ACPI_PCI_SLOT
|
|
* driver and call it here again. If we've already created the
|
|
* pci_slot, the interface will simply bump the refcount.
|
|
*/
|
|
pci_slot = pci_create_slot(bus, devnr, name, slot);
|
|
if (IS_ERR(pci_slot))
|
|
return PTR_ERR(pci_slot);
|
|
|
|
slot->pci_slot = pci_slot;
|
|
pci_slot->hotplug = slot;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__pci_hp_initialize);
|
|
|
|
/**
|
|
* pci_hp_add - publish hotplug slot to user space
|
|
* @slot: pointer to the &struct hotplug_slot to publish
|
|
*
|
|
* Make a hotplug slot's sysfs interface available and inform user space of its
|
|
* addition by sending a uevent. The hotplug driver must be prepared to handle
|
|
* all &struct hotplug_slot_ops callbacks from this point on.
|
|
*
|
|
* Returns 0 on success or a negative int on error.
|
|
*/
|
|
int pci_hp_add(struct hotplug_slot *slot)
|
|
{
|
|
struct pci_slot *pci_slot = slot->pci_slot;
|
|
int result;
|
|
|
|
result = fs_add_slot(pci_slot);
|
|
if (result)
|
|
return result;
|
|
|
|
kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
|
|
mutex_lock(&pci_hp_mutex);
|
|
list_add(&slot->slot_list, &pci_hotplug_slot_list);
|
|
mutex_unlock(&pci_hp_mutex);
|
|
dbg("Added slot %s to the list\n", hotplug_slot_name(slot));
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_hp_add);
|
|
|
|
/**
|
|
* pci_hp_deregister - deregister a hotplug_slot with the PCI hotplug subsystem
|
|
* @slot: pointer to the &struct hotplug_slot to deregister
|
|
*
|
|
* The @slot must have been registered with the pci hotplug subsystem
|
|
* previously with a call to pci_hp_register().
|
|
*
|
|
* Returns 0 if successful, anything else for an error.
|
|
*/
|
|
void pci_hp_deregister(struct hotplug_slot *slot)
|
|
{
|
|
pci_hp_del(slot);
|
|
pci_hp_destroy(slot);
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_hp_deregister);
|
|
|
|
/**
|
|
* pci_hp_del - unpublish hotplug slot from user space
|
|
* @slot: pointer to the &struct hotplug_slot to unpublish
|
|
*
|
|
* Remove a hotplug slot's sysfs interface.
|
|
*
|
|
* Returns 0 on success or a negative int on error.
|
|
*/
|
|
void pci_hp_del(struct hotplug_slot *slot)
|
|
{
|
|
struct hotplug_slot *temp;
|
|
|
|
if (WARN_ON(!slot))
|
|
return;
|
|
|
|
mutex_lock(&pci_hp_mutex);
|
|
temp = get_slot_from_name(hotplug_slot_name(slot));
|
|
if (WARN_ON(temp != slot)) {
|
|
mutex_unlock(&pci_hp_mutex);
|
|
return;
|
|
}
|
|
|
|
list_del(&slot->slot_list);
|
|
mutex_unlock(&pci_hp_mutex);
|
|
dbg("Removed slot %s from the list\n", hotplug_slot_name(slot));
|
|
fs_remove_slot(slot->pci_slot);
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_hp_del);
|
|
|
|
/**
|
|
* pci_hp_destroy - remove hotplug slot from in-kernel use
|
|
* @slot: pointer to the &struct hotplug_slot to destroy
|
|
*
|
|
* Destroy a PCI slot used by a hotplug driver. Once this has been called,
|
|
* the driver may no longer invoke hotplug_slot_name() to get the slot's
|
|
* unique name. The driver no longer needs to handle a ->reset_slot callback
|
|
* from this point on.
|
|
*
|
|
* Returns 0 on success or a negative int on error.
|
|
*/
|
|
void pci_hp_destroy(struct hotplug_slot *slot)
|
|
{
|
|
struct pci_slot *pci_slot = slot->pci_slot;
|
|
|
|
slot->pci_slot = NULL;
|
|
pci_slot->hotplug = NULL;
|
|
pci_destroy_slot(pci_slot);
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_hp_destroy);
|
|
|
|
/**
|
|
* pci_hp_change_slot_info - changes the slot's information structure in the core
|
|
* @slot: pointer to the slot whose info has changed
|
|
* @info: pointer to the info copy into the slot's info structure
|
|
*
|
|
* @slot must have been registered with the pci
|
|
* hotplug subsystem previously with a call to pci_hp_register().
|
|
*
|
|
* Returns 0 if successful, anything else for an error.
|
|
*/
|
|
int pci_hp_change_slot_info(struct hotplug_slot *slot,
|
|
struct hotplug_slot_info *info)
|
|
{
|
|
if (!slot || !info)
|
|
return -ENODEV;
|
|
|
|
memcpy(slot->info, info, sizeof(struct hotplug_slot_info));
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(pci_hp_change_slot_info);
|
|
|
|
static int __init pci_hotplug_init(void)
|
|
{
|
|
int result;
|
|
|
|
result = cpci_hotplug_init(debug);
|
|
if (result) {
|
|
err("cpci_hotplug_init with error %d\n", result);
|
|
return result;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
device_initcall(pci_hotplug_init);
|
|
|
|
/*
|
|
* not really modular, but the easiest way to keep compat with existing
|
|
* bootargs behaviour is to continue using module_param here.
|
|
*/
|
|
module_param(debug, bool, 0644);
|
|
MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
|