IPoIB: Handle 4K IB MTU for UD (datagram) mode
[linux-2.6] / drivers / acpi / event.c
1 /*
2  * event.c - exporting ACPI events via procfs
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  */
8
9 #include <linux/spinlock.h>
10 #include <linux/proc_fs.h>
11 #include <linux/init.h>
12 #include <linux/poll.h>
13 #include <acpi/acpi_drivers.h>
14 #include <net/netlink.h>
15 #include <net/genetlink.h>
16
17 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
18 ACPI_MODULE_NAME("event");
19
20 #ifdef CONFIG_ACPI_PROC_EVENT
21 /* Global vars for handling event proc entry */
22 static DEFINE_SPINLOCK(acpi_system_event_lock);
23 int event_is_open = 0;
24 extern struct list_head acpi_bus_event_list;
25 extern wait_queue_head_t acpi_bus_event_queue;
26
27 static int acpi_system_open_event(struct inode *inode, struct file *file)
28 {
29         spin_lock_irq(&acpi_system_event_lock);
30
31         if (event_is_open)
32                 goto out_busy;
33
34         event_is_open = 1;
35
36         spin_unlock_irq(&acpi_system_event_lock);
37         return 0;
38
39       out_busy:
40         spin_unlock_irq(&acpi_system_event_lock);
41         return -EBUSY;
42 }
43
44 static ssize_t
45 acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
46                        loff_t * ppos)
47 {
48         int result = 0;
49         struct acpi_bus_event event;
50         static char str[ACPI_MAX_STRING];
51         static int chars_remaining = 0;
52         static char *ptr;
53
54         if (!chars_remaining) {
55                 memset(&event, 0, sizeof(struct acpi_bus_event));
56
57                 if ((file->f_flags & O_NONBLOCK)
58                     && (list_empty(&acpi_bus_event_list)))
59                         return -EAGAIN;
60
61                 result = acpi_bus_receive_event(&event);
62                 if (result)
63                         return result;
64
65                 chars_remaining = sprintf(str, "%s %s %08x %08x\n",
66                                           event.device_class ? event.
67                                           device_class : "<unknown>",
68                                           event.bus_id ? event.
69                                           bus_id : "<unknown>", event.type,
70                                           event.data);
71                 ptr = str;
72         }
73
74         if (chars_remaining < count) {
75                 count = chars_remaining;
76         }
77
78         if (copy_to_user(buffer, ptr, count))
79                 return -EFAULT;
80
81         *ppos += count;
82         chars_remaining -= count;
83         ptr += count;
84
85         return count;
86 }
87
88 static int acpi_system_close_event(struct inode *inode, struct file *file)
89 {
90         spin_lock_irq(&acpi_system_event_lock);
91         event_is_open = 0;
92         spin_unlock_irq(&acpi_system_event_lock);
93         return 0;
94 }
95
96 static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait)
97 {
98         poll_wait(file, &acpi_bus_event_queue, wait);
99         if (!list_empty(&acpi_bus_event_list))
100                 return POLLIN | POLLRDNORM;
101         return 0;
102 }
103
104 static const struct file_operations acpi_system_event_ops = {
105         .open = acpi_system_open_event,
106         .read = acpi_system_read_event,
107         .release = acpi_system_close_event,
108         .poll = acpi_system_poll_event,
109 };
110 #endif  /* CONFIG_ACPI_PROC_EVENT */
111
112 /* ACPI notifier chain */
113 static BLOCKING_NOTIFIER_HEAD(acpi_chain_head);
114
115 int acpi_notifier_call_chain(struct acpi_device *dev, u32 type, u32 data)
116 {
117         struct acpi_bus_event event;
118
119         strcpy(event.device_class, dev->pnp.device_class);
120         strcpy(event.bus_id, dev->pnp.bus_id);
121         event.type = type;
122         event.data = data;
123         return (blocking_notifier_call_chain(&acpi_chain_head, 0, (void *)&event)
124                         == NOTIFY_BAD) ? -EINVAL : 0;
125 }
126 EXPORT_SYMBOL(acpi_notifier_call_chain);
127
128 int register_acpi_notifier(struct notifier_block *nb)
129 {
130         return blocking_notifier_chain_register(&acpi_chain_head, nb);
131 }
132 EXPORT_SYMBOL(register_acpi_notifier);
133
134 int unregister_acpi_notifier(struct notifier_block *nb)
135 {
136         return blocking_notifier_chain_unregister(&acpi_chain_head, nb);
137 }
138 EXPORT_SYMBOL(unregister_acpi_notifier);
139
140 #ifdef CONFIG_NET
141 static unsigned int acpi_event_seqnum;
142 struct acpi_genl_event {
143         acpi_device_class device_class;
144         char bus_id[15];
145         u32 type;
146         u32 data;
147 };
148
149 /* attributes of acpi_genl_family */
150 enum {
151         ACPI_GENL_ATTR_UNSPEC,
152         ACPI_GENL_ATTR_EVENT,   /* ACPI event info needed by user space */
153         __ACPI_GENL_ATTR_MAX,
154 };
155 #define ACPI_GENL_ATTR_MAX (__ACPI_GENL_ATTR_MAX - 1)
156
157 /* commands supported by the acpi_genl_family */
158 enum {
159         ACPI_GENL_CMD_UNSPEC,
160         ACPI_GENL_CMD_EVENT,    /* kernel->user notifications for ACPI events */
161         __ACPI_GENL_CMD_MAX,
162 };
163 #define ACPI_GENL_CMD_MAX (__ACPI_GENL_CMD_MAX - 1)
164
165 #define ACPI_GENL_FAMILY_NAME           "acpi_event"
166 #define ACPI_GENL_VERSION               0x01
167 #define ACPI_GENL_MCAST_GROUP_NAME      "acpi_mc_group"
168
169 static struct genl_family acpi_event_genl_family = {
170         .id = GENL_ID_GENERATE,
171         .name = ACPI_GENL_FAMILY_NAME,
172         .version = ACPI_GENL_VERSION,
173         .maxattr = ACPI_GENL_ATTR_MAX,
174 };
175
176 static struct genl_multicast_group acpi_event_mcgrp = {
177         .name = ACPI_GENL_MCAST_GROUP_NAME,
178 };
179
180 int acpi_bus_generate_netlink_event(const char *device_class,
181                                       const char *bus_id,
182                                       u8 type, int data)
183 {
184         struct sk_buff *skb;
185         struct nlattr *attr;
186         struct acpi_genl_event *event;
187         void *msg_header;
188         int size;
189         int result;
190
191         /* allocate memory */
192         size = nla_total_size(sizeof(struct acpi_genl_event)) +
193             nla_total_size(0);
194
195         skb = genlmsg_new(size, GFP_ATOMIC);
196         if (!skb)
197                 return -ENOMEM;
198
199         /* add the genetlink message header */
200         msg_header = genlmsg_put(skb, 0, acpi_event_seqnum++,
201                                  &acpi_event_genl_family, 0,
202                                  ACPI_GENL_CMD_EVENT);
203         if (!msg_header) {
204                 nlmsg_free(skb);
205                 return -ENOMEM;
206         }
207
208         /* fill the data */
209         attr =
210             nla_reserve(skb, ACPI_GENL_ATTR_EVENT,
211                         sizeof(struct acpi_genl_event));
212         if (!attr) {
213                 nlmsg_free(skb);
214                 return -EINVAL;
215         }
216
217         event = nla_data(attr);
218         if (!event) {
219                 nlmsg_free(skb);
220                 return -EINVAL;
221         }
222
223         memset(event, 0, sizeof(struct acpi_genl_event));
224
225         strcpy(event->device_class, device_class);
226         strcpy(event->bus_id, bus_id);
227         event->type = type;
228         event->data = data;
229
230         /* send multicast genetlink message */
231         result = genlmsg_end(skb, msg_header);
232         if (result < 0) {
233                 nlmsg_free(skb);
234                 return result;
235         }
236
237         result =
238             genlmsg_multicast(skb, 0, acpi_event_mcgrp.id, GFP_ATOMIC);
239         if (result)
240                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
241                                   "Failed to send a Genetlink message!\n"));
242         return 0;
243 }
244
245 EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
246
247 static int acpi_event_genetlink_init(void)
248 {
249         int result;
250
251         result = genl_register_family(&acpi_event_genl_family);
252         if (result)
253                 return result;
254
255         result = genl_register_mc_group(&acpi_event_genl_family,
256                                         &acpi_event_mcgrp);
257         if (result)
258                 genl_unregister_family(&acpi_event_genl_family);
259
260         return result;
261 }
262
263 #else
264 int acpi_bus_generate_netlink_event(const char *device_class,
265                                       const char *bus_id,
266                                       u8 type, int data)
267 {
268         return 0;
269 }
270
271 EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
272
273 static int acpi_event_genetlink_init(void)
274 {
275         return -ENODEV;
276 }
277 #endif
278
279 static int __init acpi_event_init(void)
280 {
281 #ifdef CONFIG_ACPI_PROC_EVENT
282         struct proc_dir_entry *entry;
283 #endif
284         int error = 0;
285
286         if (acpi_disabled)
287                 return 0;
288
289         /* create genetlink for acpi event */
290         error = acpi_event_genetlink_init();
291         if (error)
292                 printk(KERN_WARNING PREFIX
293                        "Failed to create genetlink family for ACPI event\n");
294
295 #ifdef CONFIG_ACPI_PROC_EVENT
296         /* 'event' [R] */
297         entry = create_proc_entry("event", S_IRUSR, acpi_root_dir);
298         if (entry)
299                 entry->proc_fops = &acpi_system_event_ops;
300         else
301                 return -ENODEV;
302 #endif
303
304         return 0;
305 }
306
307 fs_initcall(acpi_event_init);