Kernel Functions for Drivers ldi_ioctl(9F)
NAME
ldi_ioctl - send an ioctl to a device
SYNOPSIS
#include
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 operation 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 dev-
ice entry point for the device specified by the layered han-
dle. 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.SunOS 5.11 Last change: 3 June 2003 1
Kernel Functions for Drivers ldi_ioctl(9F)
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 contains the FMODELS bits that enable the target driver to determine the data model of the process which originated the ioctl and performany necessary conversions. See ddi_model_convert_from(9F)
for more information. STREAM IOCTLS For a general description of streams ioctls seestreamio(7I). ldi_ioctl() supports a number of streams
ioctls, using layered handles in the place of file descrip-
tors. When issuing streams ioctls the FKIOCTL parametershould be specified. The possible return values for sup-
ported ioctl commands are also documented in streamio(7I). The following streams ioctls are supported:I_PLINK Behaves as documented in streamio(7I). The lay-
ered handle lh should point to the streams mul-
tiplexer. The arg parameter should point to a layered handle for another streams driver.I_UNPLINK Behaves as documented in streamio(7I)). The
layered handle lh should point to the streamsmultiplexer. The arg parameter is the multi-
plexor 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 dev-
ice, 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 ALSO
streamio(7I), ddi_model_convert_from(9F)
SunOS 5.11 Last change: 3 June 2003 2