samaio - Pseudo Device Driver for AIO
The pseudo driver, samaio, allows you to attach a QFS file
to a character device, which can then be accessed through
that device. setfa -q attaches a QFS file to samaio. When
you open a file with the -q attribute set, you use the char-
acter device. Samaio translates access to the character
device into I/O on the underlying QFS file. This is useful
for aio because raw device I/O is faster than file system
Samaio is controlled through /dev/samaioctl - this is the
only device exported during attach, and is minor number 0.
QFS communicates with samaio through ioctls on this device.
When a file is attached to samaio, character devices are
exported in /dev/rsamaio. These devices are identified by
their minor number. Minor devices are tracked with state
structures handled with ddi_soft_state(9F).
The command ls displays a character device for files with
the -q attribute set, The command sls displays a regular
file with its current length for files with the -q attribute
EACCES Permission denied.
EBUSY The device was opened exclusively by another
EFAULT The argument was a bad address.
EINVAL Invalid argument.
EIO An I/O error occurred.
ENOTTY This indicates that the device does not sup-
port the requested ioctl function.
ENXIO During opening, the device did not exist.
/dev/samaioctl Master control device
/dev/rsamaio/n Character device for file n
/kernel/drv/samaio 32-bit driver
Driver configuration file. (Should not
driver.conf(4), devfsadm(1M), setfa(1), sam_setfa(3)