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> | |
f18e439d | 11 | #include <linux/seq_file.h> |
1da177e4 LT |
12 | #include <linux/interrupt.h> |
13 | ||
97a41e26 AB |
14 | #include "internals.h" |
15 | ||
4a733ee1 | 16 | static struct proc_dir_entry *root_irq_dir; |
1da177e4 LT |
17 | |
18 | #ifdef CONFIG_SMP | |
19 | ||
f18e439d | 20 | static int irq_affinity_proc_show(struct seq_file *m, void *v) |
1da177e4 | 21 | { |
08678b08 | 22 | struct irq_desc *desc = irq_to_desc((long)m->private); |
d036e67b | 23 | const struct cpumask *mask = &desc->affinity; |
42ee2b74 AK |
24 | |
25 | #ifdef CONFIG_GENERIC_PENDING_IRQ | |
26 | if (desc->status & IRQ_MOVE_PENDING) | |
27 | mask = &desc->pending_mask; | |
28 | #endif | |
f18e439d AD |
29 | seq_cpumask(m, mask); |
30 | seq_putc(m, '\n'); | |
31 | return 0; | |
1da177e4 LT |
32 | } |
33 | ||
25d61578 JK |
34 | #ifndef is_affinity_mask_valid |
35 | #define is_affinity_mask_valid(val) 1 | |
36 | #endif | |
37 | ||
1da177e4 | 38 | int no_irq_affinity; |
f18e439d AD |
39 | static ssize_t irq_affinity_proc_write(struct file *file, |
40 | const char __user *buffer, size_t count, loff_t *pos) | |
1da177e4 | 41 | { |
f18e439d | 42 | unsigned int irq = (int)(long)PDE(file->f_path.dentry->d_inode)->data; |
0de26520 | 43 | cpumask_var_t new_value; |
f18e439d | 44 | int err; |
1da177e4 | 45 | |
08678b08 | 46 | if (!irq_to_desc(irq)->chip->set_affinity || no_irq_affinity || |
950f4427 | 47 | irq_balancing_disabled(irq)) |
1da177e4 LT |
48 | return -EIO; |
49 | ||
0de26520 RR |
50 | if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) |
51 | return -ENOMEM; | |
52 | ||
53 | err = cpumask_parse_user(buffer, count, new_value); | |
1da177e4 | 54 | if (err) |
0de26520 | 55 | goto free_cpumask; |
1da177e4 | 56 | |
6bdf197b | 57 | if (!is_affinity_mask_valid(new_value)) { |
0de26520 RR |
58 | err = -EINVAL; |
59 | goto free_cpumask; | |
60 | } | |
25d61578 | 61 | |
1da177e4 LT |
62 | /* |
63 | * Do not allow disabling IRQs completely - it's a too easy | |
64 | * way to make the system unusable accidentally :-) At least | |
65 | * one online CPU still has to be targeted. | |
66 | */ | |
0de26520 | 67 | if (!cpumask_intersects(new_value, cpu_online_mask)) { |
eee45269 IK |
68 | /* Special case for empty set - allow the architecture |
69 | code to set default SMP affinity. */ | |
0de26520 RR |
70 | err = irq_select_affinity_usr(irq) ? -EINVAL : count; |
71 | } else { | |
72 | irq_set_affinity(irq, new_value); | |
73 | err = count; | |
74 | } | |
75 | ||
76 | free_cpumask: | |
77 | free_cpumask_var(new_value); | |
78 | return err; | |
1da177e4 LT |
79 | } |
80 | ||
f18e439d | 81 | static int irq_affinity_proc_open(struct inode *inode, struct file *file) |
18404756 | 82 | { |
f18e439d | 83 | return single_open(file, irq_affinity_proc_show, PDE(inode)->data); |
18404756 MK |
84 | } |
85 | ||
f18e439d AD |
86 | static const struct file_operations irq_affinity_proc_fops = { |
87 | .open = irq_affinity_proc_open, | |
88 | .read = seq_read, | |
89 | .llseek = seq_lseek, | |
90 | .release = single_release, | |
91 | .write = irq_affinity_proc_write, | |
92 | }; | |
93 | ||
94 | static int default_affinity_show(struct seq_file *m, void *v) | |
95 | { | |
d036e67b | 96 | seq_cpumask(m, irq_default_affinity); |
f18e439d AD |
97 | seq_putc(m, '\n'); |
98 | return 0; | |
99 | } | |
100 | ||
101 | static ssize_t default_affinity_write(struct file *file, | |
102 | const char __user *buffer, size_t count, loff_t *ppos) | |
18404756 | 103 | { |
d036e67b | 104 | cpumask_var_t new_value; |
f18e439d | 105 | int err; |
18404756 | 106 | |
d036e67b RR |
107 | if (!alloc_cpumask_var(&new_value, GFP_KERNEL)) |
108 | return -ENOMEM; | |
109 | ||
110 | err = cpumask_parse_user(buffer, count, new_value); | |
18404756 | 111 | if (err) |
d036e67b | 112 | goto out; |
18404756 | 113 | |
d036e67b RR |
114 | if (!is_affinity_mask_valid(new_value)) { |
115 | err = -EINVAL; | |
116 | goto out; | |
117 | } | |
18404756 MK |
118 | |
119 | /* | |
120 | * Do not allow disabling IRQs completely - it's a too easy | |
121 | * way to make the system unusable accidentally :-) At least | |
122 | * one online CPU still has to be targeted. | |
123 | */ | |
d036e67b RR |
124 | if (!cpumask_intersects(new_value, cpu_online_mask)) { |
125 | err = -EINVAL; | |
126 | goto out; | |
127 | } | |
18404756 | 128 | |
d036e67b RR |
129 | cpumask_copy(irq_default_affinity, new_value); |
130 | err = count; | |
18404756 | 131 | |
d036e67b RR |
132 | out: |
133 | free_cpumask_var(new_value); | |
134 | return err; | |
18404756 | 135 | } |
f18e439d AD |
136 | |
137 | static int default_affinity_open(struct inode *inode, struct file *file) | |
138 | { | |
139 | return single_open(file, default_affinity_show, NULL); | |
140 | } | |
141 | ||
142 | static const struct file_operations default_affinity_proc_fops = { | |
143 | .open = default_affinity_open, | |
144 | .read = seq_read, | |
145 | .llseek = seq_lseek, | |
146 | .release = single_release, | |
147 | .write = default_affinity_write, | |
148 | }; | |
1da177e4 LT |
149 | #endif |
150 | ||
96d97cf0 AK |
151 | static int irq_spurious_read(char *page, char **start, off_t off, |
152 | int count, int *eof, void *data) | |
153 | { | |
08678b08 | 154 | struct irq_desc *desc = irq_to_desc((long) data); |
96d97cf0 AK |
155 | return sprintf(page, "count %u\n" |
156 | "unhandled %u\n" | |
157 | "last_unhandled %u ms\n", | |
08678b08 YL |
158 | desc->irq_count, |
159 | desc->irqs_unhandled, | |
160 | jiffies_to_msecs(desc->last_unhandled)); | |
96d97cf0 AK |
161 | } |
162 | ||
1da177e4 LT |
163 | #define MAX_NAMELEN 128 |
164 | ||
165 | static int name_unique(unsigned int irq, struct irqaction *new_action) | |
166 | { | |
08678b08 | 167 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 | 168 | struct irqaction *action; |
d2d9433a DA |
169 | unsigned long flags; |
170 | int ret = 1; | |
1da177e4 | 171 | |
d2d9433a DA |
172 | spin_lock_irqsave(&desc->lock, flags); |
173 | for (action = desc->action ; action; action = action->next) { | |
1da177e4 | 174 | if ((action != new_action) && action->name && |
d2d9433a DA |
175 | !strcmp(new_action->name, action->name)) { |
176 | ret = 0; | |
177 | break; | |
178 | } | |
179 | } | |
180 | spin_unlock_irqrestore(&desc->lock, flags); | |
181 | return ret; | |
1da177e4 LT |
182 | } |
183 | ||
184 | void register_handler_proc(unsigned int irq, struct irqaction *action) | |
185 | { | |
186 | char name [MAX_NAMELEN]; | |
08678b08 | 187 | struct irq_desc *desc = irq_to_desc(irq); |
1da177e4 | 188 | |
08678b08 | 189 | if (!desc->dir || action->dir || !action->name || |
1da177e4 LT |
190 | !name_unique(irq, action)) |
191 | return; | |
192 | ||
193 | memset(name, 0, MAX_NAMELEN); | |
194 | snprintf(name, MAX_NAMELEN, "%s", action->name); | |
195 | ||
196 | /* create /proc/irq/1234/handler/ */ | |
08678b08 | 197 | action->dir = proc_mkdir(name, desc->dir); |
1da177e4 LT |
198 | } |
199 | ||
200 | #undef MAX_NAMELEN | |
201 | ||
202 | #define MAX_NAMELEN 10 | |
203 | ||
2c6927a3 | 204 | void register_irq_proc(unsigned int irq, struct irq_desc *desc) |
1da177e4 LT |
205 | { |
206 | char name [MAX_NAMELEN]; | |
96d97cf0 | 207 | struct proc_dir_entry *entry; |
1da177e4 | 208 | |
08678b08 | 209 | if (!root_irq_dir || (desc->chip == &no_irq_chip) || desc->dir) |
1da177e4 LT |
210 | return; |
211 | ||
212 | memset(name, 0, MAX_NAMELEN); | |
213 | sprintf(name, "%d", irq); | |
214 | ||
215 | /* create /proc/irq/1234 */ | |
08678b08 | 216 | desc->dir = proc_mkdir(name, root_irq_dir); |
1da177e4 LT |
217 | |
218 | #ifdef CONFIG_SMP | |
f18e439d | 219 | /* create /proc/irq/<irq>/smp_affinity */ |
08678b08 | 220 | proc_create_data("smp_affinity", 0600, desc->dir, |
f18e439d | 221 | &irq_affinity_proc_fops, (void *)(long)irq); |
1da177e4 | 222 | #endif |
96d97cf0 | 223 | |
08678b08 | 224 | entry = create_proc_entry("spurious", 0444, desc->dir); |
96d97cf0 AK |
225 | if (entry) { |
226 | entry->data = (void *)(long)irq; | |
227 | entry->read_proc = irq_spurious_read; | |
228 | } | |
1da177e4 LT |
229 | } |
230 | ||
231 | #undef MAX_NAMELEN | |
232 | ||
233 | void unregister_handler_proc(unsigned int irq, struct irqaction *action) | |
234 | { | |
08678b08 YL |
235 | if (action->dir) { |
236 | struct irq_desc *desc = irq_to_desc(irq); | |
d3c60047 | 237 | |
08678b08 YL |
238 | remove_proc_entry(action->dir->name, desc->dir); |
239 | } | |
1da177e4 LT |
240 | } |
241 | ||
3786fc71 | 242 | static void register_default_affinity_proc(void) |
18404756 MK |
243 | { |
244 | #ifdef CONFIG_SMP | |
f18e439d AD |
245 | proc_create("irq/default_smp_affinity", 0600, NULL, |
246 | &default_affinity_proc_fops); | |
18404756 MK |
247 | #endif |
248 | } | |
249 | ||
1da177e4 LT |
250 | void init_irq_proc(void) |
251 | { | |
2c6927a3 YL |
252 | unsigned int irq; |
253 | struct irq_desc *desc; | |
1da177e4 LT |
254 | |
255 | /* create /proc/irq */ | |
256 | root_irq_dir = proc_mkdir("irq", NULL); | |
257 | if (!root_irq_dir) | |
258 | return; | |
259 | ||
18404756 MK |
260 | register_default_affinity_proc(); |
261 | ||
1da177e4 LT |
262 | /* |
263 | * Create entries for all existing IRQs. | |
264 | */ | |
0b8f1efa YL |
265 | for_each_irq_desc(irq, desc) { |
266 | if (!desc) | |
267 | continue; | |
268 | ||
2c6927a3 | 269 | register_irq_proc(irq, desc); |
0b8f1efa | 270 | } |
1da177e4 LT |
271 | } |
272 |