Storage-class memory device nodes
Applications access storage-class memory devices by device nodes. Normally, Ubuntu Server 22.04 LTS creates a device node for each storage increment. Alternatively, use the mknod command to create one.
The device driver uses a device name of the form
/dev/scm<x> for an entire block device. In the name,
<x> is one or two lowercase letters.
You can partition a block device into up to seven partitions. If you use partitions, the device driver numbers them from 1 - 7. The partitions then have device nodes of the form /dev/scm<x><n>, where <n> is a number in the range 1 - 7, for example /dev/scma1.
The following example shows two block devices,
scma and scmb, where scma has one
partition,
scma1.
# lsblk
NAME MAJ:MIN RM SIZE RO MOUNTPOINT
scma 252:0 0 16G 0
`-scma1 252:1 0 16G 0
scmb 252:8 0 16G 0 You must load the module before you check for the device node.
To check whether there already is a node, use for example, lsblk to list all block devices and look for "scm" entries.
To create storage-class memory
device nodes issue commands of the
form:
# mknod /dev/scma1 b <major> 1
# mknod /dev/scma2 b <major> 2
# mknod /dev/scma3 b <major> 3
...