1 files changed, 159 insertions, 0 deletions

diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
new file mode 100644
index 000000000000..85d08daa6600
--- /dev/null
+++ b/kernel/irq/proc.c
@@ -0,0 +1,159 @@
+/*
+ * 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>
+
+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];
+
+void __attribute__((weak))
+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);
+}
+
+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))
+                return -EINVAL;
+
+        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);
+}
+