How to get a list of major number -> driver associations

Question

The Linux Programming Interface states:

Each device driver registers its association with a specific major device ID, and this association provides the connection between the device special file and the device driver.

Is it possible to obtain the list of those associations?

Solution

Documentation/admin-guide/devices.txt in the kernel source code documents the allocation process and lists all the allocated device numbers. sd gets a whole bunch of major device numbers because of the large number of devices it can handle: major 8 covers /dev/sda to /dev/sdp, major 65 covers /dev/sdq to /dev/sdaf, 66 /dev/sdag to /dev/sdav and so on all the way to 135 for /dev/sdig to /dev/sdiv (for a total of 256 disk devices).