https://github.com/torvalds/linux
Tip revision: fa8410b355251fd30341662a40ac6b22d3e38468 authored by Linus Torvalds on 21 August 2016, 23:14:10 UTC
Linux 4.8-rc3
Linux 4.8-rc3
Tip revision: fa8410b
event.c
/*
* event.c - exporting ACPI events via procfs
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
*
*/
#include <linux/spinlock.h>
#include <linux/export.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/gfp.h>
#include <linux/acpi.h>
#include <net/netlink.h>
#include <net/genetlink.h>
#include "internal.h"
#define _COMPONENT ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME("event");
/* ACPI notifier chain */
static BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
int acpi_notifier_call_chain(struct acpi_device *dev, u32 type, u32 data)
{
struct acpi_bus_event event;
strcpy(event.device_class, dev->pnp.device_class);
strcpy(event.bus_id, dev->pnp.bus_id);
event.type = type;
event.data = data;
return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event)
== NOTIFY_BAD) ? -EINVAL : 0;
}
EXPORT_SYMBOL(acpi_notifier_call_chain);
int register_acpi_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_register(&acpi_chain_head, nb);
}
EXPORT_SYMBOL(register_acpi_notifier);
int unregister_acpi_notifier(struct notifier_block *nb)
{
return blocking_notifier_chain_unregister(&acpi_chain_head, nb);
}
EXPORT_SYMBOL(unregister_acpi_notifier);
#ifdef CONFIG_NET
static unsigned int acpi_event_seqnum;
struct acpi_genl_event {
acpi_device_class device_class;
char bus_id[15];
u32 type;
u32 data;
};
/* attributes of acpi_genl_family */
enum {
ACPI_GENL_ATTR_UNSPEC,
ACPI_GENL_ATTR_EVENT, /* ACPI event info needed by user space */
__ACPI_GENL_ATTR_MAX,
};
#define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1)
/* commands supported by the acpi_genl_family */
enum {
ACPI_GENL_CMD_UNSPEC,
ACPI_GENL_CMD_EVENT, /* kernel->user notifications for ACPI events */
__ACPI_GENL_CMD_MAX,
};
#define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1)
#define ACPI_GENL_FAMILY_NAME "acpi_event"
#define ACPI_GENL_VERSION 0x01
#define ACPI_GENL_MCAST_GROUP_NAME "acpi_mc_group"
static const struct genl_multicast_group acpi_event_mcgrps[] = {
{ .name = ACPI_GENL_MCAST_GROUP_NAME, },
};
static struct genl_family acpi_event_genl_family = {
.id = GENL_ID_GENERATE,
.name = ACPI_GENL_FAMILY_NAME,
.version = ACPI_GENL_VERSION,
.maxattr = ACPI_GENL_ATTR_MAX,
.mcgrps = acpi_event_mcgrps,
.n_mcgrps = ARRAY_SIZE(acpi_event_mcgrps),
};
int acpi_bus_generate_netlink_event(const char *device_class,
const char *bus_id,
u8 type, int data)
{
struct sk_buff *skb;
struct nlattr *attr;
struct acpi_genl_event *event;
void *msg_header;
int size;
/* allocate memory */
size = nla_total_size(sizeof(struct acpi_genl_event)) +
nla_total_size(0);
skb = genlmsg_new(size, GFP_ATOMIC);
if (!skb)
return -ENOMEM;
/* add the genetlink message header */
msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++,
&acpi_event_genl_family, 0,
ACPI_GENL_CMD_EVENT);
if (!msg_header) {
nlmsg_free(skb);
return -ENOMEM;
}
/* fill the data */
attr =
nla_reserve(skb, ACPI_GENL_ATTR_EVENT,
sizeof(struct acpi_genl_event));
if (!attr) {
nlmsg_free(skb);
return -EINVAL;
}
event = nla_data(attr);
memset(event, 0, sizeof(struct acpi_genl_event));
strcpy(event->device_class, device_class);
strcpy(event->bus_id, bus_id);
event->type = type;
event->data = data;
/* send multicast genetlink message */
genlmsg_end(skb, msg_header);
genlmsg_multicast(&acpi_event_genl_family, skb, 0, 0, GFP_ATOMIC);
return 0;
}
EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
static int acpi_event_genetlink_init(void)
{
return genl_register_family(&acpi_event_genl_family);
}
#else
int acpi_bus_generate_netlink_event(const char *device_class,
const char *bus_id,
u8 type, int data)
{
return 0;
}
EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
static int acpi_event_genetlink_init(void)
{
return -ENODEV;
}
#endif
static int __init acpi_event_init(void)
{
int error = 0;
if (acpi_disabled)
return 0;
/* create genetlink for acpi event */
error = acpi_event_genetlink_init();
if (error)
printk(KERN_WARNING PREFIX
"Failed to create genetlink family for ACPI event\n");
return 0;
}
fs_initcall(acpi_event_init);