/* * linux/kernel/irq/proc.c * * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar * * This file contains the /proc/irq/ handling code. */ #include <linux/irq.h> #include <linux/proc_fs.h> #include <linux/interrupt.h> #include "internals.h" static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS]; #ifdef CONFIG_SMP /* * The /proc/irq/<irq>/smp_affinity values: */ static struct proc_dir_entry *smp_affinity_entry[NR_IRQS]; #ifdef CONFIG_GENERIC_PENDING_IRQ void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) { /* * Save these away for later use. Re-progam when the * interrupt is pending */ set_pending_irq(irq, mask_val); } #else void proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val) { irq_affinity[irq] = mask_val; irq_desc[irq].handler->set_affinity(irq, mask_val); } #endif static int irq_affinity_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data) { int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]); if (count - len < 2) return -EINVAL; len += sprintf(page + len, "\n"); return len; } int no_irq_affinity; static int irq_affinity_write_proc(struct file *file, const char __user *buffer, unsigned long count, void *data) { unsigned int irq = (int)(long)data, full_count = count, err; cpumask_t new_value, tmp; if (!irq_desc[irq].handler->set_affinity || no_irq_affinity) return -EIO; err = cpumask_parse(buffer, count, new_value); if (err) return err; /* * Do not allow disabling IRQs completely - it's a too easy * way to make the system unusable accidentally :-) At least * one online CPU still has to be targeted. */ cpus_and(tmp, new_value, cpu_online_map); if (cpus_empty(tmp)) /* Special case for empty set - allow the architecture code to set default SMP affinity. */ return select_smp_affinity(irq) ? -EINVAL : full_count; proc_set_irq_affinity(irq, new_value); return full_count; } #endif #define MAX_NAMELEN 128 static int name_unique(unsigned int irq, struct irqaction *new_action) { struct irq_desc *desc = irq_desc + irq; struct irqaction *action; for (action = desc->action ; action; action = action->next) if ((action != new_action) && action->name && !strcmp(new_action->name, action->name)) return 0; return 1; } void register_handler_proc(unsigned int irq, struct irqaction *action) { char name [MAX_NAMELEN]; if (!irq_dir[irq] || action->dir || !action->name || !name_unique(irq, action)) return; memset(name, 0, MAX_NAMELEN); snprintf(name, MAX_NAMELEN, "%s", action->name); /* create /proc/irq/1234/handler/ */ action->dir = proc_mkdir(name, irq_dir[irq]); } #undef MAX_NAMELEN #define MAX_NAMELEN 10 void register_irq_proc(unsigned int irq) { char name [MAX_NAMELEN]; if (!root_irq_dir || (irq_desc[irq].handler == &no_irq_type) || irq_dir[irq]) return; memset(name, 0, MAX_NAMELEN); sprintf(name, "%d", irq); /* create /proc/irq/1234 */ irq_dir[irq] = proc_mkdir(name, root_irq_dir); #ifdef CONFIG_SMP { struct proc_dir_entry *entry; /* create /proc/irq/<irq>/smp_affinity */ entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]); if (entry) { entry->nlink = 1; entry->data = (void *)(long)irq; entry->read_proc = irq_affinity_read_proc; entry->write_proc = irq_affinity_write_proc; } smp_affinity_entry[irq] = entry; } #endif } #undef MAX_NAMELEN void unregister_handler_proc(unsigned int irq, struct irqaction *action) { if (action->dir) remove_proc_entry(action->dir->name, irq_dir[irq]); } void init_irq_proc(void) { int i; /* create /proc/irq */ root_irq_dir = proc_mkdir("irq", NULL); if (!root_irq_dir) return; /* * Create entries for all existing IRQs. */ for (i = 0; i < NR_IRQS; i++) register_irq_proc(i); }