ia64/linux-2.6.18-xen.hg

view kernel/irq/proc.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
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 */
9 #include <linux/irq.h>
10 #include <linux/proc_fs.h>
11 #include <linux/interrupt.h>
13 #include "internals.h"
15 static struct proc_dir_entry *root_irq_dir;
17 #ifdef CONFIG_SMP
19 #ifdef CONFIG_GENERIC_PENDING_IRQ
20 void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
21 {
22 set_balance_irq_affinity(irq, mask_val);
24 /*
25 * Save these away for later use. Re-progam when the
26 * interrupt is pending
27 */
28 set_pending_irq(irq, mask_val);
29 }
30 #else
31 void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
32 {
33 set_balance_irq_affinity(irq, mask_val);
34 irq_desc[irq].affinity = mask_val;
35 irq_desc[irq].chip->set_affinity(irq, mask_val);
36 }
37 #endif
39 static int irq_affinity_read_proc(char *page, char **start, off_t off,
40 int count, int *eof, void *data)
41 {
42 int len = cpumask_scnprintf(page, count, irq_desc[(long)data].affinity);
44 if (count - len < 2)
45 return -EINVAL;
46 len += sprintf(page + len, "\n");
47 return len;
48 }
50 int no_irq_affinity;
51 static int irq_affinity_write_proc(struct file *file, const char __user *buffer,
52 unsigned long count, void *data)
53 {
54 unsigned int irq = (int)(long)data, full_count = count, err;
55 cpumask_t new_value, tmp;
57 if (!irq_desc[irq].chip->set_affinity || no_irq_affinity)
58 return -EIO;
60 err = cpumask_parse(buffer, count, new_value);
61 if (err)
62 return err;
64 /*
65 * Do not allow disabling IRQs completely - it's a too easy
66 * way to make the system unusable accidentally :-) At least
67 * one online CPU still has to be targeted.
68 */
69 cpus_and(tmp, new_value, cpu_online_map);
70 if (cpus_empty(tmp))
71 /* Special case for empty set - allow the architecture
72 code to set default SMP affinity. */
73 return select_smp_affinity(irq) ? -EINVAL : full_count;
75 proc_set_irq_affinity(irq, new_value);
77 return full_count;
78 }
80 #endif
82 #define MAX_NAMELEN 128
84 static int name_unique(unsigned int irq, struct irqaction *new_action)
85 {
86 struct irq_desc *desc = irq_desc + irq;
87 struct irqaction *action;
89 for (action = desc->action ; action; action = action->next)
90 if ((action != new_action) && action->name &&
91 !strcmp(new_action->name, action->name))
92 return 0;
93 return 1;
94 }
96 void register_handler_proc(unsigned int irq, struct irqaction *action)
97 {
98 char name [MAX_NAMELEN];
100 if (!irq_desc[irq].dir || action->dir || !action->name ||
101 !name_unique(irq, action))
102 return;
104 memset(name, 0, MAX_NAMELEN);
105 snprintf(name, MAX_NAMELEN, "%s", action->name);
107 /* create /proc/irq/1234/handler/ */
108 action->dir = proc_mkdir(name, irq_desc[irq].dir);
109 }
111 #undef MAX_NAMELEN
113 #define MAX_NAMELEN 10
115 void register_irq_proc(unsigned int irq)
116 {
117 char name [MAX_NAMELEN];
119 if (!root_irq_dir ||
120 (irq_desc[irq].chip == &no_irq_chip) ||
121 irq_desc[irq].dir)
122 return;
124 memset(name, 0, MAX_NAMELEN);
125 sprintf(name, "%d", irq);
127 /* create /proc/irq/1234 */
128 irq_desc[irq].dir = proc_mkdir(name, root_irq_dir);
130 #ifdef CONFIG_SMP
131 {
132 struct proc_dir_entry *entry;
134 /* create /proc/irq/<irq>/smp_affinity */
135 entry = create_proc_entry("smp_affinity", 0600, irq_desc[irq].dir);
137 if (entry) {
138 entry->nlink = 1;
139 entry->data = (void *)(long)irq;
140 entry->read_proc = irq_affinity_read_proc;
141 entry->write_proc = irq_affinity_write_proc;
142 }
143 }
144 #endif
145 }
147 #undef MAX_NAMELEN
149 void unregister_handler_proc(unsigned int irq, struct irqaction *action)
150 {
151 if (action->dir)
152 remove_proc_entry(action->dir->name, irq_desc[irq].dir);
153 }
155 void init_irq_proc(void)
156 {
157 int i;
159 /* create /proc/irq */
160 root_irq_dir = proc_mkdir("irq", NULL);
161 if (!root_irq_dir)
162 return;
164 /*
165 * Create entries for all existing IRQs.
166 */
167 for (i = 0; i < NR_IRQS; i++)
168 register_irq_proc(i);
169 }