GenWQE device nodes

6.18 LPAR mode z/VM guest

GenWQE user space components use device nodes to exchange data with the GenWQE device driver.

Loading the GenWQE device driver module creates a device node of the form /dev/genwqe<n>_card for each available virtual acceleration card. <n> is an index number that identifies an individual virtual card.

Node /dev/genwqe0_card is assigned to the first card that is detected, /dev/genwqe1_card to the second card, and so on. Do not directly use these device nodes.

The nodes must grant read and write permissions to all users, for example:

# ls -l /dev/genwqe*
crwrwrw 1 root root 249, 0 Jun 30 10:01 /dev/genwqe0_card
crwrwrw 1 root root 248, 0 Jun 30 10:01 /dev/genwqe1_card

If the permissions are not crwrwrw, create a file /etc/udev/rules.d/52-genwqedevices.rules with this rule as its content:

KERNEL=="genwqe*", MODE="0666"

The new rule takes effect next time the GenWQE device driver is loaded.

Tip: Use the chmod command to temporarily set the permissions.