proc: move /proc/interrupts boilerplate code to fs/proc/interrupts.c

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
diff --git a/fs/proc/interrupts.c b/fs/proc/interrupts.c
new file mode 100644
index 0000000..05029c0
--- /dev/null
+++ b/fs/proc/interrupts.c
@@ -0,0 +1,53 @@
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irqnr.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+/*
+ * /proc/interrupts
+ */
+static void *int_seq_start(struct seq_file *f, loff_t *pos)
+{
+	return (*pos <= nr_irqs) ? pos : NULL;
+}
+
+static void *int_seq_next(struct seq_file *f, void *v, loff_t *pos)
+{
+	(*pos)++;
+	if (*pos > nr_irqs)
+		return NULL;
+	return pos;
+}
+
+static void int_seq_stop(struct seq_file *f, void *v)
+{
+	/* Nothing to do */
+}
+
+static const struct seq_operations int_seq_ops = {
+	.start = int_seq_start,
+	.next  = int_seq_next,
+	.stop  = int_seq_stop,
+	.show  = show_interrupts
+};
+
+static int interrupts_open(struct inode *inode, struct file *filp)
+{
+	return seq_open(filp, &int_seq_ops);
+}
+
+static const struct file_operations proc_interrupts_operations = {
+	.open		= interrupts_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+static int __init proc_interrupts_init(void)
+{
+	proc_create("interrupts", 0, NULL, &proc_interrupts_operations);
+	return 0;
+}
+module_init(proc_interrupts_init);