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/export.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>
ACPI: Clean up inclusions of ACPI header files Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h> inclusions and remove some inclusions of those files that aren't necessary. First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h> should not be included directly from any files that are built for CONFIG_ACPI unset, because that generally leads to build warnings about undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set, <linux/acpi.h> includes those files and for CONFIG_ACPI unset it provides stub ACPI symbols to be used in that case. Second, there are ordering dependencies between those files that always have to be met. Namely, it is required that <acpi/acpi_bus.h> be included prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the latter depends on are always there. And <acpi/acpi.h> which provides basic ACPICA type declarations should always be included prior to any other ACPI headers in CONFIG_ACPI builds. That also is taken care of including <linux/acpi.h> as appropriate. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Tony Luck <tony.luck@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff) Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-03 00:49:16 +00:00
#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 */
netlink: make nlmsg_end() and genlmsg_end() void Contrary to common expectations for an "int" return, these functions return only a positive value -- if used correctly they cannot even return 0 because the message header will necessarily be in the skb. This makes the very common pattern of if (genlmsg_end(...) < 0) { ... } be a whole bunch of dead code. Many places also simply do return nlmsg_end(...); and the caller is expected to deal with it. This also commonly (at least for me) causes errors, because it is very common to write if (my_function(...)) /* error condition */ and if my_function() does "return nlmsg_end()" this is of course wrong. Additionally, there's not a single place in the kernel that actually needs the message length returned, and if anyone needs it later then it'll be very easy to just use skb->len there. Remove this, and make the functions void. This removes a bunch of dead code as described above. The patch adds lines because I did - return nlmsg_end(...); + nlmsg_end(...); + return 0; I could have preserved all the function's return values by returning skb->len, but instead I've audited all the places calling the affected functions and found that none cared. A few places actually compared the return value with <= 0 in dump functionality, but that could just be changed to < 0 with no change in behaviour, so I opted for the more efficient version. One instance of the error I've made numerous times now is also present in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't check for <0 or <=0 and thus broke out of the loop every single time. I've preserved this since it will (I think) have caused the messages to userspace to be formatted differently with just a single message for every SKB returned to userspace. It's possible that this isn't needed for the tools that actually use this, but I don't even know what they are so couldn't test that changing this behaviour would be acceptable. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-16 21:09:00 +00:00
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);