1 files changed, 70 insertions, 0 deletions
diff --git a/fs/proc/devices.c b/fs/proc/devices.c
new file mode 100644
index 000000000000..59ee7da959c9
--- /dev/null
+++ b/fs/proc/devices.c
@@ -0,0 +1,70 @@
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static int devinfo_show(struct seq_file *f, void *v)
+{
+	int i = *(loff_t *) v;
+
+	if (i < CHRDEV_MAJOR_HASH_SIZE) {
+		if (i == 0)
+			seq_printf(f, "Character devices:\n");
+		chrdev_show(f, i);
+	}
+#ifdef CONFIG_BLOCK
+	else {
+		i -= CHRDEV_MAJOR_HASH_SIZE;
+		if (i == 0)
+			seq_printf(f, "\nBlock devices:\n");
+		blkdev_show(f, i);
+	}
+#endif
+	return 0;
+}
+
+static void *devinfo_start(struct seq_file *f, loff_t *pos)
+{
+	if (*pos < (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE))
+		return pos;
+	return NULL;
+}
+
+static void *devinfo_next(struct seq_file *f, void *v, loff_t *pos)
+{
+	(*pos)++;
+	if (*pos >= (BLKDEV_MAJOR_HASH_SIZE + CHRDEV_MAJOR_HASH_SIZE))
+		return NULL;
+	return pos;
+}
+
+static void devinfo_stop(struct seq_file *f, void *v)
+{
+	/* Nothing to do */
+}
+
+static const struct seq_operations devinfo_ops = {
+	.start = devinfo_start,
+	.next  = devinfo_next,
+	.stop  = devinfo_stop,
+	.show  = devinfo_show
+};
+
+static int devinfo_open(struct inode *inode, struct file *filp)
+{
+	return seq_open(filp, &devinfo_ops);
+}
+
+static const struct file_operations proc_devinfo_operations = {
+	.open		= devinfo_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+static int __init proc_devices_init(void)
+{
+	proc_create("devices", 0, NULL, &proc_devinfo_operations);
+	return 0;
+}
+module_init(proc_devices_init);