linux/drivers/acpi/event.c

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/*
* 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/proc_fs.h>
#include <linux/init.h>
#include <linux/poll.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/gfp.h>
#include <acpi/acpi_drivers.h>
#include <net/netlink.h>
#include <net/genetlink.h>
#include "internal.h"
#define _COMPONENT ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME("event");
#ifdef CONFIG_ACPI_PROC_EVENT
/* Global vars for handling event proc entry */
static DEFINE_SPINLOCK(acpi_system_event_lock);
int event_is_open = 0;
extern struct list_head acpi_bus_event_list;
extern wait_queue_head_t acpi_bus_event_queue;
static int acpi_system_open_event(struct inode *inode, struct file *file)
{
spin_lock_irq(&acpi_system_event_lock);
if (event_is_open)
goto out_busy;
event_is_open = 1;
spin_unlock_irq(&acpi_system_event_lock);
return 0;
out_busy:
spin_unlock_irq(&acpi_system_event_lock);
return -EBUSY;
}
static ssize_t
acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
loff_t * ppos)
{
int result = 0;
struct acpi_bus_event event;
static char str[ACPI_MAX_STRING];
static int chars_remaining = 0;
static char *ptr;
if (!chars_remaining) {
memset(&event, 0, sizeof(struct acpi_bus_event));
if ((file->f_flags & O_NONBLOCK)
&& (list_empty(&acpi_bus_event_list)))
return -EAGAIN;
result = acpi_bus_receive_event(&event);
if (result)
return result;
chars_remaining = sprintf(str, "%s %s %08x %08x\n",
event.device_class ? event.
device_class : "<unknown>",
event.bus_id ? event.
bus_id : "<unknown>", event.type,
event.data);
ptr = str;
}
if (chars_remaining < count) {
count = chars_remaining;
}
if (copy_to_user(buffer, ptr, count))
return -EFAULT;
*ppos += count;
chars_remaining -= count;
ptr += count;
return count;
}
static int acpi_system_close_event(struct inode *inode, struct file *file)
{
spin_lock_irq(&acpi_system_event_lock);
event_is_open = 0;
spin_unlock_irq(&acpi_system_event_lock);
return 0;
}
static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait)
{
poll_wait(file, &acpi_bus_event_queue, wait);
if (!list_empty(&acpi_bus_event_list))
return POLLIN | POLLRDNORM;
return 0;
}
static const struct file_operations acpi_system_event_ops = {
.owner = THIS_MODULE,
.open = acpi_system_open_event,
.read = acpi_system_read_event,
.release = acpi_system_close_event,
.poll = acpi_system_poll_event,
};
#endif /* CONFIG_ACPI_PROC_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 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,
};
static struct genl_multicast_group acpi_event_mcgrp = {
.name = ACPI_GENL_MCAST_GROUP_NAME,
};
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;
int result;
/* 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);
if (!event) {
nlmsg_free(skb);
return -EINVAL;
}
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 */
result = genlmsg_end(skb, msg_header);
if (result < 0) {
nlmsg_free(skb);
return result;
}
netlink: change return-value logic of netlink_broadcast() Currently, netlink_broadcast() reports errors to the caller if no messages at all were delivered: 1) If, at least, one message has been delivered correctly, returns 0. 2) Otherwise, if no messages at all were delivered due to skb_clone() failure, return -ENOBUFS. 3) Otherwise, if there are no listeners, return -ESRCH. With this patch, the caller knows if the delivery of any of the messages to the listeners have failed: 1) If it fails to deliver any message (for whatever reason), return -ENOBUFS. 2) Otherwise, if all messages were delivered OK, returns 0. 3) Otherwise, if no listeners, return -ESRCH. In the current ctnetlink code and in Netfilter in general, we can add reliable logging and connection tracking event delivery by dropping the packets whose events were not successfully delivered over Netlink. Of course, this option would be settable via /proc as this approach reduces performance (in terms of filtered connections per seconds by a stateful firewall) but providing reliable logging and event delivery (for conntrackd) in return. This patch also changes some clients of netlink_broadcast() that may report ENOBUFS errors via printk. This error handling is not of any help. Instead, the userspace daemons that are listening to those netlink messages should resync themselves with the kernel-side if they hit ENOBUFS. BTW, netlink_broadcast() clients include those that call cn_netlink_send(), nlmsg_multicast() and genlmsg_multicast() since they internally call netlink_broadcast() and return its error value. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-06 07:56:36 +00:00
genlmsg_multicast(skb, 0, acpi_event_mcgrp.id, GFP_ATOMIC);
return 0;
}
EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
static int acpi_event_genetlink_init(void)
{
int result;
result = genl_register_family(&acpi_event_genl_family);
if (result)
return result;
result = genl_register_mc_group(&acpi_event_genl_family,
&acpi_event_mcgrp);
if (result)
genl_unregister_family(&acpi_event_genl_family);
return result;
}
#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)
{
#ifdef CONFIG_ACPI_PROC_EVENT
struct proc_dir_entry *entry;
#endif
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");
#ifdef CONFIG_ACPI_PROC_EVENT
/* 'event' [R] */
entry = proc_create("event", S_IRUSR, acpi_root_dir,
&acpi_system_event_ops);
if (!entry)
return -ENODEV;
#endif
return 0;
}
fs_initcall(acpi_event_init);