]>
Commit | Line | Data |
---|---|---|
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 | ||
13 | static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS]; | |
14 | ||
15 | #ifdef CONFIG_SMP | |
16 | ||
17 | /* | |
18 | * The /proc/irq/<irq>/smp_affinity values: | |
19 | */ | |
20 | static struct proc_dir_entry *smp_affinity_entry[NR_IRQS]; | |
21 | ||
22 | void __attribute__((weak)) | |
23 | proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) | |
24 | { | |
25 | irq_affinity[irq] = mask_val; | |
26 | irq_desc[irq].handler->set_affinity(irq, mask_val); | |
27 | } | |
28 | ||
29 | static int irq_affinity_read_proc(char *page, char **start, off_t off, | |
30 | int count, int *eof, void *data) | |
31 | { | |
32 | int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]); | |
33 | ||
34 | if (count - len < 2) | |
35 | return -EINVAL; | |
36 | len += sprintf(page + len, "\n"); | |
37 | return len; | |
38 | } | |
39 | ||
40 | int no_irq_affinity; | |
41 | static int irq_affinity_write_proc(struct file *file, const char __user *buffer, | |
42 | unsigned long count, void *data) | |
43 | { | |
44 | unsigned int irq = (int)(long)data, full_count = count, err; | |
45 | cpumask_t new_value, tmp; | |
46 | ||
47 | if (!irq_desc[irq].handler->set_affinity || no_irq_affinity) | |
48 | return -EIO; | |
49 | ||
50 | err = cpumask_parse(buffer, count, new_value); | |
51 | if (err) | |
52 | return err; | |
53 | ||
54 | /* | |
55 | * Do not allow disabling IRQs completely - it's a too easy | |
56 | * way to make the system unusable accidentally :-) At least | |
57 | * one online CPU still has to be targeted. | |
58 | */ | |
59 | cpus_and(tmp, new_value, cpu_online_map); | |
60 | if (cpus_empty(tmp)) | |
61 | return -EINVAL; | |
62 | ||
63 | proc_set_irq_affinity(irq, new_value); | |
64 | ||
65 | return full_count; | |
66 | } | |
67 | ||
68 | #endif | |
69 | ||
70 | #define MAX_NAMELEN 128 | |
71 | ||
72 | static int name_unique(unsigned int irq, struct irqaction *new_action) | |
73 | { | |
74 | struct irq_desc *desc = irq_desc + irq; | |
75 | struct irqaction *action; | |
76 | ||
77 | for (action = desc->action ; action; action = action->next) | |
78 | if ((action != new_action) && action->name && | |
79 | !strcmp(new_action->name, action->name)) | |
80 | return 0; | |
81 | return 1; | |
82 | } | |
83 | ||
84 | void register_handler_proc(unsigned int irq, struct irqaction *action) | |
85 | { | |
86 | char name [MAX_NAMELEN]; | |
87 | ||
88 | if (!irq_dir[irq] || action->dir || !action->name || | |
89 | !name_unique(irq, action)) | |
90 | return; | |
91 | ||
92 | memset(name, 0, MAX_NAMELEN); | |
93 | snprintf(name, MAX_NAMELEN, "%s", action->name); | |
94 | ||
95 | /* create /proc/irq/1234/handler/ */ | |
96 | action->dir = proc_mkdir(name, irq_dir[irq]); | |
97 | } | |
98 | ||
99 | #undef MAX_NAMELEN | |
100 | ||
101 | #define MAX_NAMELEN 10 | |
102 | ||
103 | void register_irq_proc(unsigned int irq) | |
104 | { | |
105 | char name [MAX_NAMELEN]; | |
106 | ||
107 | if (!root_irq_dir || | |
108 | (irq_desc[irq].handler == &no_irq_type) || | |
109 | irq_dir[irq]) | |
110 | return; | |
111 | ||
112 | memset(name, 0, MAX_NAMELEN); | |
113 | sprintf(name, "%d", irq); | |
114 | ||
115 | /* create /proc/irq/1234 */ | |
116 | irq_dir[irq] = proc_mkdir(name, root_irq_dir); | |
117 | ||
118 | #ifdef CONFIG_SMP | |
119 | { | |
120 | struct proc_dir_entry *entry; | |
121 | ||
122 | /* create /proc/irq/<irq>/smp_affinity */ | |
123 | entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); | |
124 | ||
125 | if (entry) { | |
126 | entry->nlink = 1; | |
127 | entry->data = (void *)(long)irq; | |
128 | entry->read_proc = irq_affinity_read_proc; | |
129 | entry->write_proc = irq_affinity_write_proc; | |
130 | } | |
131 | smp_affinity_entry[irq] = entry; | |
132 | } | |
133 | #endif | |
134 | } | |
135 | ||
136 | #undef MAX_NAMELEN | |
137 | ||
138 | void unregister_handler_proc(unsigned int irq, struct irqaction *action) | |
139 | { | |
140 | if (action->dir) | |
141 | remove_proc_entry(action->dir->name, irq_dir[irq]); | |
142 | } | |
143 | ||
144 | void init_irq_proc(void) | |
145 | { | |
146 | int i; | |
147 | ||
148 | /* create /proc/irq */ | |
149 | root_irq_dir = proc_mkdir("irq", NULL); | |
150 | if (!root_irq_dir) | |
151 | return; | |
152 | ||
153 | /* | |
154 | * Create entries for all existing IRQs. | |
155 | */ | |
156 | for (i = 0; i < NR_IRQS; i++) | |
157 | register_irq_proc(i); | |
158 | } | |
159 |