fs: Add function to get cdev by mountpath

This is useful to know for the bootloader spec implementation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

fs/fs.c

@@ -283,6 +283,19 @@ static struct fs_device_d *get_fsdevice_by_path(const char *path)
 	return fs_dev_root;
 }
 
+/*
+ * get_cdev_by_mountpath - return the cdev the given path
+ *                         is mounted on
+ */
+struct cdev *get_cdev_by_mountpath(const char *path)
+{
+	struct fs_device_d *fsdev;
+
+	fsdev = get_fsdevice_by_path(path);
+
+	return fsdev->cdev;
+}
+
 char *get_mounted_path(const char *path)
 {
 	struct fs_device_d *fdev;

include/fs.h

@@ -184,6 +184,8 @@ char *normalise_link(const char *pathname, const char* symlink);
 
 char *get_mounted_path(const char *path);
 
+struct cdev *get_cdev_by_mountpath(const char *path);
+
 /* Register a new filesystem driver */
 int register_fs_driver(struct fs_driver_d *fsdrv);