Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Adrian Bunk | 97a41e2 | 2006-01-08 01:02:17 -0800 | [diff] [blame] | 13 | #include "internals.h" |
| 14 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Ashok Raj | 54d5d42 | 2005-09-06 15:16:15 -0700 | [diff] [blame] | 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) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | { |
| 36 | irq_affinity[irq] = mask_val; |
| 37 | irq_desc[irq].handler->set_affinity(irq, mask_val); |
| 38 | } |
Ashok Raj | 54d5d42 | 2005-09-06 15:16:15 -0700 | [diff] [blame] | 39 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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)) |
Ivan Kokshaysky | eee4526 | 2006-01-06 00:12:21 -0800 | [diff] [blame] | 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; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |