Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/kernel/irq/proc.c | |
3 | * | |
4 | * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar | |
5 | * | |
6 | * This file contains the /proc/irq/ handling code. | |
7 | */ | |
8 | ||
9 | #include <linux/irq.h> | |
10 | #include <linux/proc_fs.h> | |
11 | #include <linux/interrupt.h> | |
12 | ||
97a41e26 AB |
13 | #include "internals.h" |
14 | ||
4a733ee1 | 15 | static struct proc_dir_entry *root_irq_dir; |
1da177e4 LT |
16 | |
17 | #ifdef CONFIG_SMP | |
18 | ||
1da177e4 LT |
19 | static int irq_affinity_read_proc(char *page, char **start, off_t off, |
20 | int count, int *eof, void *data) | |
21 | { | |
42ee2b74 AK |
22 | struct irq_desc *desc = irq_desc + (long)data; |
23 | cpumask_t *mask = &desc->affinity; | |
24 | int len; | |
25 | ||
26 | #ifdef CONFIG_GENERIC_PENDING_IRQ | |
27 | if (desc->status & IRQ_MOVE_PENDING) | |
28 | mask = &desc->pending_mask; | |
29 | #endif | |
30 | len = cpumask_scnprintf(page, count, *mask); | |
1da177e4 LT |
31 | |
32 | if (count - len < 2) | |
33 | return -EINVAL; | |
34 | len += sprintf(page + len, "\n"); | |
35 | return len; | |
36 | } | |
37 | ||
25d61578 JK |
38 | #ifndef is_affinity_mask_valid |
39 | #define is_affinity_mask_valid(val) 1 | |
40 | #endif | |
41 | ||
1da177e4 LT |
42 | int no_irq_affinity; |
43 | static int irq_affinity_write_proc(struct file *file, const char __user *buffer, | |
44 | unsigned long count, void *data) | |
45 | { | |
46 | unsigned int irq = (int)(long)data, full_count = count, err; | |
18404756 | 47 | cpumask_t new_value; |
1da177e4 | 48 | |
6e2ac664 | 49 | if (!irq_desc[irq].chip->set_affinity || no_irq_affinity || |
950f4427 | 50 | irq_balancing_disabled(irq)) |
1da177e4 LT |
51 | return -EIO; |
52 | ||
01a3ee2b | 53 | err = cpumask_parse_user(buffer, count, new_value); |
1da177e4 LT |
54 | if (err) |
55 | return err; | |
56 | ||
25d61578 JK |
57 | if (!is_affinity_mask_valid(new_value)) |
58 | return -EINVAL; | |
59 | ||
1da177e4 LT |
60 | /* |
61 | * Do not allow disabling IRQs completely - it's a too easy | |
62 | * way to make the system unusable accidentally :-) At least | |
63 | * one online CPU still has to be targeted. | |
64 | */ | |
18404756 | 65 | if (!cpus_intersects(new_value, cpu_online_map)) |
eee45269 IK |
66 | /* Special case for empty set - allow the architecture |
67 | code to set default SMP affinity. */ | |
18404756 | 68 | return irq_select_affinity(irq) ? -EINVAL : full_count; |
1da177e4 | 69 | |
771ee3b0 | 70 | irq_set_affinity(irq, new_value); |
1da177e4 LT |
71 | |
72 | return full_count; | |
73 | } | |
74 | ||
18404756 MK |
75 | static int default_affinity_read(char *page, char **start, off_t off, |
76 | int count, int *eof, void *data) | |
77 | { | |
78 | int len = cpumask_scnprintf(page, count, irq_default_affinity); | |
79 | if (count - len < 2) | |
80 | return -EINVAL; | |
81 | len += sprintf(page + len, "\n"); | |
82 | return len; | |
83 | } | |
84 | ||
85 | static int default_affinity_write(struct file *file, const char __user *buffer, | |
86 | unsigned long count, void *data) | |
87 | { | |
88 | unsigned int full_count = count, err; | |
89 | cpumask_t new_value; | |
90 | ||
91 | err = cpumask_parse_user(buffer, count, new_value); | |
92 | if (err) | |
93 | return err; | |
94 | ||
95 | if (!is_affinity_mask_valid(new_value)) | |
96 | return -EINVAL; | |
97 | ||
98 | /* | |
99 | * Do not allow disabling IRQs completely - it's a too easy | |
100 | * way to make the system unusable accidentally :-) At least | |
101 | * one online CPU still has to be targeted. | |
102 | */ | |
103 | if (!cpus_intersects(new_value, cpu_online_map)) | |
104 | return -EINVAL; | |
105 | ||
106 | irq_default_affinity = new_value; | |
107 | ||
108 | return full_count; | |
109 | } | |
1da177e4 LT |
110 | #endif |
111 | ||
96d97cf0 AK |
112 | static int irq_spurious_read(char *page, char **start, off_t off, |
113 | int count, int *eof, void *data) | |
114 | { | |
115 | struct irq_desc *d = &irq_desc[(long) data]; | |
116 | return sprintf(page, "count %u\n" | |
117 | "unhandled %u\n" | |
118 | "last_unhandled %u ms\n", | |
119 | d->irq_count, | |
120 | d->irqs_unhandled, | |
121 | jiffies_to_msecs(d->last_unhandled)); | |
122 | } | |
123 | ||
1da177e4 LT |
124 | #define MAX_NAMELEN 128 |
125 | ||
126 | static int name_unique(unsigned int irq, struct irqaction *new_action) | |
127 | { | |
128 | struct irq_desc *desc = irq_desc + irq; | |
129 | struct irqaction *action; | |
d2d9433a DA |
130 | unsigned long flags; |
131 | int ret = 1; | |
1da177e4 | 132 | |
d2d9433a DA |
133 | spin_lock_irqsave(&desc->lock, flags); |
134 | for (action = desc->action ; action; action = action->next) { | |
1da177e4 | 135 | if ((action != new_action) && action->name && |
d2d9433a DA |
136 | !strcmp(new_action->name, action->name)) { |
137 | ret = 0; | |
138 | break; | |
139 | } | |
140 | } | |
141 | spin_unlock_irqrestore(&desc->lock, flags); | |
142 | return ret; | |
1da177e4 LT |
143 | } |
144 | ||
145 | void register_handler_proc(unsigned int irq, struct irqaction *action) | |
146 | { | |
147 | char name [MAX_NAMELEN]; | |
148 | ||
4a733ee1 | 149 | if (!irq_desc[irq].dir || action->dir || !action->name || |
1da177e4 LT |
150 | !name_unique(irq, action)) |
151 | return; | |
152 | ||
153 | memset(name, 0, MAX_NAMELEN); | |
154 | snprintf(name, MAX_NAMELEN, "%s", action->name); | |
155 | ||
156 | /* create /proc/irq/1234/handler/ */ | |
4a733ee1 | 157 | action->dir = proc_mkdir(name, irq_desc[irq].dir); |
1da177e4 LT |
158 | } |
159 | ||
160 | #undef MAX_NAMELEN | |
161 | ||
162 | #define MAX_NAMELEN 10 | |
163 | ||
164 | void register_irq_proc(unsigned int irq) | |
165 | { | |
166 | char name [MAX_NAMELEN]; | |
96d97cf0 | 167 | struct proc_dir_entry *entry; |
1da177e4 LT |
168 | |
169 | if (!root_irq_dir || | |
f1c2662c | 170 | (irq_desc[irq].chip == &no_irq_chip) || |
4a733ee1 | 171 | irq_desc[irq].dir) |
1da177e4 LT |
172 | return; |
173 | ||
174 | memset(name, 0, MAX_NAMELEN); | |
175 | sprintf(name, "%d", irq); | |
176 | ||
177 | /* create /proc/irq/1234 */ | |
4a733ee1 | 178 | irq_desc[irq].dir = proc_mkdir(name, root_irq_dir); |
1da177e4 LT |
179 | |
180 | #ifdef CONFIG_SMP | |
181 | { | |
1da177e4 | 182 | /* create /proc/irq/<irq>/smp_affinity */ |
4a733ee1 | 183 | entry = create_proc_entry("smp_affinity", 0600, irq_desc[irq].dir); |
1da177e4 LT |
184 | |
185 | if (entry) { | |
1da177e4 LT |
186 | entry->data = (void *)(long)irq; |
187 | entry->read_proc = irq_affinity_read_proc; | |
188 | entry->write_proc = irq_affinity_write_proc; | |
189 | } | |
1da177e4 LT |
190 | } |
191 | #endif | |
96d97cf0 AK |
192 | |
193 | entry = create_proc_entry("spurious", 0444, irq_desc[irq].dir); | |
194 | if (entry) { | |
195 | entry->data = (void *)(long)irq; | |
196 | entry->read_proc = irq_spurious_read; | |
197 | } | |
1da177e4 LT |
198 | } |
199 | ||
200 | #undef MAX_NAMELEN | |
201 | ||
202 | void unregister_handler_proc(unsigned int irq, struct irqaction *action) | |
203 | { | |
204 | if (action->dir) | |
4a733ee1 | 205 | remove_proc_entry(action->dir->name, irq_desc[irq].dir); |
1da177e4 LT |
206 | } |
207 | ||
18404756 MK |
208 | void register_default_affinity_proc(void) |
209 | { | |
210 | #ifdef CONFIG_SMP | |
211 | struct proc_dir_entry *entry; | |
212 | ||
213 | /* create /proc/irq/default_smp_affinity */ | |
214 | entry = create_proc_entry("default_smp_affinity", 0600, root_irq_dir); | |
215 | if (entry) { | |
216 | entry->data = NULL; | |
217 | entry->read_proc = default_affinity_read; | |
218 | entry->write_proc = default_affinity_write; | |
219 | } | |
220 | #endif | |
221 | } | |
222 | ||
1da177e4 LT |
223 | void init_irq_proc(void) |
224 | { | |
225 | int i; | |
226 | ||
227 | /* create /proc/irq */ | |
228 | root_irq_dir = proc_mkdir("irq", NULL); | |
229 | if (!root_irq_dir) | |
230 | return; | |
231 | ||
18404756 MK |
232 | register_default_affinity_proc(); |
233 | ||
1da177e4 LT |
234 | /* |
235 | * Create entries for all existing IRQs. | |
236 | */ | |
237 | for (i = 0; i < NR_IRQS; i++) | |
238 | register_irq_proc(i); | |
239 | } | |
240 |