Understanding the Diagnostic Subsystem for AIX

pdiag_close

Purpose

Frees up PDIAGEX Kernel Extension resources.

Syntax

#include <sys/pdiagex_dds.h>
#include <sy/pdiag_def.h>
 
int pdiag_close( handle )
pdiag_info_handle_t  handle;

Description

The pdiag_close() function frees the DMA and interrupt channels, if they were initialized. This function also masks the DMA channel; that is, you are not required to do a pdiag_dd_dma_complete(). Any memory that was allocated, pinned, or cross-memory attached is detached, unpinned, and freed appropriately.

If this is the last use of the user's interrupt-handler routine, it is unloaded from kernel memory.

Both this routine and pdiag_open() share a common lock while executing to prevent simultaneous resource allocation and deallocation. If a call is made to this routine or pdiag_open() while the lock is being held by a previous call, the calling process will sleep until the routine is available.

Note

All pdiag_dd_dma_setup() ) calls should be matched with a pdiag_dd_dma_complete() call prior to calling this routine. Any outstanding DMA operations results in the failure of this routine.

Execution Environment

The pdiag_close() function can be called from the process environment only.

Parameters

Parameter	Description
handle	Pointer to pdiag_info_handle_t structure which is returned from pdiag_open().

Return Value

The pdiag_close function returns one of the following values:

Return Value	Description
DGX_OK	The operation was successful. The errno is not set.
DGX_INVALID_HANDLE	Specified handle has been closed or was not generated by the (pdiag_open) call. The errno is not set.
DGX_OUTSTANDINGDMA_FAIL	An outstanding DMA operation is preventing closure. The errno is not set.

Related Information

pdiag_open subroutine.