// SPDX-License-Identifier: GPL-2.0/* * 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> * */ #define pr_fmt(fmt) "ACPI: " fmt #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" /* ACPI notifier chain */static BLOCKING_NOTIFIER_HEAD(acpi_chain_head); int acpi_notifier_call_chain(const char *device_class,			     const char *bus_id, u32 type, u32 data){	struct acpi_bus_event event; 	strscpy(event.device_class, device_class);	strscpy(event.bus_id, 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_NETstatic 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 __ro_after_init = {	.module = THIS_MODULE,	.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)); 	strscpy(event->device_class, device_class, sizeof(event->device_class));	strscpy(event->bus_id, bus_id, sizeof(event->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 __init acpi_event_genetlink_init(void){	return genl_register_family(&acpi_event_genl_family);} #elseint 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; 	if (acpi_disabled)		return 0; 	/* create genetlink for acpi event */	error = acpi_event_genetlink_init();	if (error)		pr_warn("Failed to create genetlink family for ACPI event\n"); 	return 0;} fs_initcall(acpi_event_init);