ACPI: Export events via generic netlink

Upon ACPI events, send an "acpi_event" via Generic Netlink.
This is in addition to /proc/acpi/event, which remains intact for now.

Thanks to Jamal for his great help.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index e5084ececb6ff7f004326a3fcdf24828c45e2f0a..6b2658c9624245c7de284623058b4312bb96ff0e 100644 (file)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -292,6 +292,10 @@ int acpi_bus_generate_event(struct acpi_device *device, u8 type, int data)
        if (!device)
                return -EINVAL;
 
+       if (acpi_bus_generate_genetlink_event(device, type, data))
+               printk(KERN_WARNING PREFIX
+                       "Failed to generate an ACPI event via genetlink!\n");
+
        /* drop event on the floor if no one's listening */
        if (!event_is_open)
                return 0;

diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c
index 3b23562e6f92d195ea24dad4b1eb24131b6f519a..98627b02f5475c1556d30dfd0b8ab4cf94f95d73 100644 (file)
--- a/drivers/acpi/event.c
+++ b/drivers/acpi/event.c
@@ -11,6 +11,8 @@
 #include <linux/init.h>
 #include <linux/poll.h>
 #include <acpi/acpi_drivers.h>
+#include <net/netlink.h>
+#include <net/genetlink.h>
 
 #define _COMPONENT             ACPI_SYSTEM_COMPONENT
 ACPI_MODULE_NAME("event");
@@ -48,7 +50,6 @@ acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
        static int chars_remaining = 0;
        static char *ptr;
 
-
        if (!chars_remaining) {
                memset(&event, 0, sizeof(struct acpi_bus_event));
 
@@ -106,23 +107,174 @@ static const struct file_operations acpi_system_event_ops = {
        .poll = acpi_system_poll_event,
 };
 
+#ifdef CONFIG_NET
+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_NAME         "acpi_event"
+#define ACPI_GENL_VERSION      0x01
+
+static struct genl_family acpi_event_genl_family = {
+       .id = GENL_ID_GENERATE,
+       .name = ACPI_GENL_NAME,
+       .version = ACPI_GENL_VERSION,
+       .maxattr = ACPI_GENL_ATTR_MAX,
+};
+
+/* .doit: standard command callback */
+static int acpi_genl_cmd_event(struct sk_buff *skb, struct genl_info *info)
+{
+       struct acpi_genl_event *event = info->userhdr;
+
+       if (!event)
+               ACPI_DEBUG_PRINT((ACPI_DB_WARN, "ACPI event: NULL\n"));
+
+       return 0;
+}
+
+static struct genl_ops acpi_event_genl_ops = {
+       .cmd = ACPI_GENL_CMD_EVENT,
+       .doit = acpi_genl_cmd_event,
+};
+
+int acpi_bus_generate_genetlink_event(struct acpi_device *device,
+                                     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->pnp.device_class);
+       strcpy(event->bus_id, device->dev.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;
+       }
+
+       result =
+           genlmsg_multicast(skb, 0, acpi_event_genl_family.id, GFP_ATOMIC);
+       if (result)
+               ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+                                 "Failed to send a Genetlink message!\n"));
+       return 0;
+}
+EXPORT_SYMBOL(acpi_bus_generate_genetlink_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_ops(&acpi_event_genl_family, &acpi_event_genl_ops);
+       if (result)
+               genl_unregister_family(&acpi_event_genl_family);
+
+       return result;
+}
+
+#else
+int acpi_bus_generate_genetlink_event(struct acpi_device *device, u8 type,
+                                     int data)
+{
+       return 0;
+}
+EXPORT_SYMBOL(acpi_bus_generate_genetlink_event);
+
+static int acpi_event_genetlink_init(void)
+{
+       return -ENODEV;
+}
+#endif
+
 static int __init acpi_event_init(void)
 {
        struct proc_dir_entry *entry;
        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");
+
        /* 'event' [R] */
        entry = create_proc_entry("event", S_IRUSR, acpi_root_dir);
        if (entry)
                entry->proc_fops = &acpi_system_event_ops;
-       else {
-               error = -ENODEV;
-       }
-       return error;
+       else
+               return -ENODEV;
+
+       return 0;
 }
 
-subsys_initcall(acpi_event_init);
+fs_initcall(acpi_event_init);

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index c6fa5e023bc78289b92cb4d5b5da5d94f3df0266..5e3dcf3299bf90c68ae537de9c07d9fbbb9d69f6 100644 (file)
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -321,7 +321,8 @@ struct acpi_bus_event {
 };
 
 extern struct kset acpi_subsys;
-
+extern int acpi_bus_generate_genetlink_event(struct acpi_device *device,
+                                               u8 type, int data);
 /*
  * External Functions
  */