VIOBLK(4D) 4D VIOBLK(4D)

NAME


vioblk - virtio block device

SYNOPSIS


/dev/dsk/cXt0d0 /dev/rdsk/cXt0d0

DESCRIPTION


The vioblk driver is a blkdev(4D) based device that supports the virtio
para-virtualization block device specification which is commonly used by
many hypervisors and emulators. The device supports what the specification
calls the more commonly found `legacy' interface for devices.

The driver supports the following features, if offered by the device:

- Volatile write-cache

- Discarding unused sectors (ala TRIM, UNMAP)

- Read-only device support

- Physical block sizes that are distinct from logical 512-byte blocks

- Synthesized disk geometry

APPLICATION PROGRAMMING INTERFACE


For each device instance, a blkdev(4D) instance is created and treated as
an independent controller with a single device, meaning that the cX part of
cXt0d0 will vary for each device. Because the driver leverages the
blkdev(4D) framework, most standard disk manipulation utilities will
function such as diskinfo(8) for discovering devices, format(8) for
manipulating partition tables, iostat(8) for seeing device I/O statistics,
and a subset of the dkio(4I) ioctl requests to retrieve information about
the device.

ARCHITECTURE


The vioblk driver is only supported on x86.

FILES


/dev/dsk/cXt0d0 Block device minor node.

/dev/rdsk/cXt0d0 Character device minor node.

/kernel/drv/amd64/vioblk x86 device driver.

SEE ALSO


blkdev(4D), virtio(4D), dkio(4I), diskinfo(8)

Virtual I/O Device (VIRTIO) Version 1.1,
https://docs.oasis-open.org/virtio/virtio/v1.1/virtio-v1.1.html, April,
2019.

OmniOS August 28, 2021 OmniOS