NAME

vmd —

Intel Volume Management Device driver

SYNOPSIS

To compile this driver into the kernel, place the following lines in your kernel configuration file:

device vmd

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

vmd_load="YES"

DESCRIPTION

This driver attaches to Intel VMD devices, representing them as PCI-to-PCI bridges and providing access to children PCI devices via new PCI domains. Intel VMD is used by Intel's VROC (Virtual RAID on chip) to manage NVMe drives.

LOADER TUNABLES

The following tunables are settable via loader(8) or sysctl(8):

hw.vmd.max_msi: Limits number of Message Signaled Interrupt (MSI) vectors allowed to each child device. VMD can't distinguish MSI vectors of the same device, so there are no benefits to have more than one, unless it is required by specific device driver. Defaults to 1.
hw.vmd.max_msix: Limits number of Extended Message Signaled Interrupt (MSI-X) vectors allowed to each child device. VMD has limited number of interrupt vectors to map children interrupts into, so to avoid/reduce sharing children devices/drivers need to be constrained. Defaults to 3.

HISTORY

The vmd driver first appeared in FreeBSD 13.0.

NAME

SYNOPSIS

DESCRIPTION

LOADER TUNABLES

SEE ALSO

HISTORY