ldi_ioctl(9F) Kernel Functions for Drivers ldi_ioctl(9F)NAMEldi_ioctl - send an ioctl to a device
SYNOPSIS
#include <sys/sunldi.h>
int ldi_ioctl(ldi_handle_t lh, int cmd, intptr_t arg, int mode,
cred_t *cr, int *rvalp);
PARAMETERS
lh Layered handle.
cr Pointer to a credential structure used to open a device.
rvalp Caller return value. (May be set by driver and is valid only
if the ioctl() succeeds).
cmd Command argument. Interpreted by driver ioctl() as the opera‐
tion to be performed.
arg Driver parameter. Argument interpretation is driver dependent
and usually depends on the command type.
mode Bit field that contains:
FKIOCTL Inform the target device that the ioctl originated
from within the kernel.
DESCRIPTION
The ldi_ioctl() function passes an ioctl request to the device entry
point for the device specified by the layered handle. This operation is
supported for block, character, and streams devices.
If arg is interpreted as a pointer (that is, as not an immediate
value) and the data pointed to by arg is in the kernels address space,
the FKIOCTL flag should be set. This indicates to the target driver
that no data model conversion is necessary.
If the caller of ldi_ioctl() is not the originator of the ioctl data
pointed to by arg, (for example, when passing on an ioctl request from
a user process), the caller must pass on the mode parameter from the
original ioctl. This is because the mode parameter contains the con‐
tains the FMODELS bits that enable the target driver to determine the
data model of the process which originated the ioctl and perform any
necessary conversions. See ddi_model_convert_from(9F) for more informa‐
tion.
STREAM IOCTLS
For a general description of streams ioctls see streamio(7I).
ldi_ioctl() supports a number of streams ioctls, using layered handles
in the place of file descriptors. When issuing streams ioctls the
FKIOCTL parameter should be specified. The possible return values for
supported ioctl commands are also documented in streamio(7I).
The following streams ioctls are supported:
I_PLINK Behaves as documented in streamio(7I). The layered handle
lh should point to the streams multiplexer. The arg param‐
eter should point to a layered handle for another streams
driver.
I_UNPLINK Behaves as documented in streamio(7I)). The layered han‐
dle lh should point to the streams multiplexer. The arg
parameter is the multiplexor ID number returned by I_PLINK
when the streams were linked.
RETURN VALUES
The ldi_ioctl() function returns 0 upon success. If a failure occurs
before the request is passed on to the device, possible return values
are shown below. Otherwise any other error number may be returned by
the device.
EINVAL Invalid input parameters.
ENOTSUP Operation is not supported for this device.
CONTEXT
These functions can be called from user or kernel context.
SEE ALSOstreamio(7I), ddi_model_convert_from(9F)SunOS 5.11 3 June 2003 ldi_ioctl(9F)