IBM Advanced SerialRAID Adapters SA33-3285-02, User Manual

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SSA_GET_ENTRY_POINT SSA Adapter Device Driver ioctl Operation
Purpose
To allow another kernel extension, typically a SSA head device driver, to determine the
direct call entry point for the SSA adapter device driver. This operation is the entry point
through which the head device driver communicates with the adapter device driver. The
address that is supplied is valid only while the calling kernel extension holds an open
file descriptor for the SSA adapter device driver. This operation is not valid for a user
process.
Description
The arg parameter specifies the address of a SSA_GetEntryPointParms_t structure in
kernel address space. The SSA_GetEntryPointParms_t structure is defined in the
/usr/include/sys/ssa.h file.
On completion of the operation, the fields in the SSA_GetEntryPointParms_t structure
are modified as follows:
EntryPoint
Address of the direct call entry point for the SSA adapter device driver, which
is used to submit operations from a head device driver.
InterruptPriority
The off level interrupt priority at which the calling kernel extension is called
back for completion of commands that are started by calling the direct call
entry point.
Return Values
When completed successfully, this operation returns a value of 0. Otherwise, a value of
-1 is returned and the errno global variable is set to the following value:
EINVAL
Indicates that the caller was not in kernel mode.
Files
/dev/ssa0, /dev/ssa1,..., /dev/ssan
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