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 | ||
97a41e26 AB |
13 | #include "internals.h" |
14 | ||
1da177e4 LT |
15 | static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS]; |
16 | ||
17 | #ifdef CONFIG_SMP | |
18 | ||
19 | /* | |
20 | * The /proc/irq/<irq>/smp_affinity values: | |
21 | */ | |
22 | static struct proc_dir_entry *smp_affinity_entry[NR_IRQS]; | |
23 | ||
54d5d424 AR |
24 | #ifdef CONFIG_GENERIC_PENDING_IRQ |
25 | void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) | |
26 | { | |
27 | /* | |
28 | * Save these away for later use. Re-progam when the | |
29 | * interrupt is pending | |
30 | */ | |
31 | set_pending_irq(irq, mask_val); | |
32 | } | |
33 | #else | |
34 | void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) | |
1da177e4 LT |
35 | { |
36 | irq_affinity[irq] = mask_val; | |
37 | irq_desc[irq].handler->set_affinity(irq, mask_val); | |
38 | } | |
54d5d424 | 39 | #endif |
1da177e4 LT |
40 | |
41 | static int irq_affinity_read_proc(char *page, char **start, off_t off, | |
42 | int count, int *eof, void *data) | |
43 | { | |
44 | int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]); | |
45 | ||
46 | if (count - len < 2) | |
47 | return -EINVAL; | |
48 | len += sprintf(page + len, "\n"); | |
49 | return len; | |
50 | } | |
51 | ||
52 | int no_irq_affinity; | |
53 | static int irq_affinity_write_proc(struct file *file, const char __user *buffer, | |
54 | unsigned long count, void *data) | |
55 | { | |
56 | unsigned int irq = (int)(long)data, full_count = count, err; | |
57 | cpumask_t new_value, tmp; | |
58 | ||
59 | if (!irq_desc[irq].handler->set_affinity || no_irq_affinity) | |
60 | return -EIO; | |
61 | ||
62 | err = cpumask_parse(buffer, count, new_value); | |
63 | if (err) | |
64 | return err; | |
65 | ||
66 | /* | |
67 | * Do not allow disabling IRQs completely - it's a too easy | |
68 | * way to make the system unusable accidentally :-) At least | |
69 | * one online CPU still has to be targeted. | |
70 | */ | |
71 | cpus_and(tmp, new_value, cpu_online_map); | |
72 | if (cpus_empty(tmp)) | |
eee45269 IK |
73 | /* Special case for empty set - allow the architecture |
74 | code to set default SMP affinity. */ | |
75 | return select_smp_affinity(irq) ? -EINVAL : full_count; | |
1da177e4 LT |
76 | |
77 | proc_set_irq_affinity(irq, new_value); | |
78 | ||
79 | return full_count; | |
80 | } | |
81 | ||
82 | #endif | |
83 | ||
84 | #define MAX_NAMELEN 128 | |
85 | ||
86 | static int name_unique(unsigned int irq, struct irqaction *new_action) | |
87 | { | |
88 | struct irq_desc *desc = irq_desc + irq; | |
89 | struct irqaction *action; | |
90 | ||
91 | for (action = desc->action ; action; action = action->next) | |
92 | if ((action != new_action) && action->name && | |
93 | !strcmp(new_action->name, action->name)) | |
94 | return 0; | |
95 | return 1; | |
96 | } | |
97 | ||
98 | void register_handler_proc(unsigned int irq, struct irqaction *action) | |
99 | { | |
100 | char name [MAX_NAMELEN]; | |
101 | ||
102 | if (!irq_dir[irq] || action->dir || !action->name || | |
103 | !name_unique(irq, action)) | |
104 | return; | |
105 | ||
106 | memset(name, 0, MAX_NAMELEN); | |
107 | snprintf(name, MAX_NAMELEN, "%s", action->name); | |
108 | ||
109 | /* create /proc/irq/1234/handler/ */ | |
110 | action->dir = proc_mkdir(name, irq_dir[irq]); | |
111 | } | |
112 | ||
113 | #undef MAX_NAMELEN | |
114 | ||
115 | #define MAX_NAMELEN 10 | |
116 | ||
117 | void register_irq_proc(unsigned int irq) | |
118 | { | |
119 | char name [MAX_NAMELEN]; | |
120 | ||
121 | if (!root_irq_dir || | |
122 | (irq_desc[irq].handler == &no_irq_type) || | |
123 | irq_dir[irq]) | |
124 | return; | |
125 | ||
126 | memset(name, 0, MAX_NAMELEN); | |
127 | sprintf(name, "%d", irq); | |
128 | ||
129 | /* create /proc/irq/1234 */ | |
130 | irq_dir[irq] = proc_mkdir(name, root_irq_dir); | |
131 | ||
132 | #ifdef CONFIG_SMP | |
133 | { | |
134 | struct proc_dir_entry *entry; | |
135 | ||
136 | /* create /proc/irq/<irq>/smp_affinity */ | |
137 | entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); | |
138 | ||
139 | if (entry) { | |
140 | entry->nlink = 1; | |
141 | entry->data = (void *)(long)irq; | |
142 | entry->read_proc = irq_affinity_read_proc; | |
143 | entry->write_proc = irq_affinity_write_proc; | |
144 | } | |
145 | smp_affinity_entry[irq] = entry; | |
146 | } | |
147 | #endif | |
148 | } | |
149 | ||
150 | #undef MAX_NAMELEN | |
151 | ||
152 | void unregister_handler_proc(unsigned int irq, struct irqaction *action) | |
153 | { | |
154 | if (action->dir) | |
155 | remove_proc_entry(action->dir->name, irq_dir[irq]); | |
156 | } | |
157 | ||
158 | void init_irq_proc(void) | |
159 | { | |
160 | int i; | |
161 | ||
162 | /* create /proc/irq */ | |
163 | root_irq_dir = proc_mkdir("irq", NULL); | |
164 | if (!root_irq_dir) | |
165 | return; | |
166 | ||
167 | /* | |
168 | * Create entries for all existing IRQs. | |
169 | */ | |
170 | for (i = 0; i < NR_IRQS; i++) | |
171 | register_irq_proc(i); | |
172 | } | |
173 |