lock_callback(D2hpci)
lock_callback --
lock hot plug callback structure
Synopsis
#include <sys/types.h>
#include <sys/hpci.h>
#include <sys/ddi.h>
pl_t lock_callback(hpci_hpcd_t *hpcd_info);
void unlock_callback(hpci_hpcd_t *hpcd_info, pl_t old_ipl);
Description
lock_callback( )
locks the HPCD instance while the HPCD data structures
are examined or modified by HPCI.
unlock_callback( )
then releases the lock.
Arguments
hpcd_info-
pointer to an
hpci_hpcd_t(D4hpci)
structure.
old_ipl-
pl value returned by the corresponding call to
lock_callback( ).
Return values
lock_callback( )
returns the
pl(D5)
priority level at which the routine was called.
This value is used later by the
unlock_callback( )
function.
unlock_callback( )
has no return value.
Usage
These routines are required in HPCD drivers.
Code that examines or modifies the
hpci_hpcd_t(D4hpci)
structure is considered critical code that must execute atomically
to preserve the integrity of the shared data structures.
lock_callback( )
sets the lock, and
unlock_callback( )
releases the lock.
The relevent data structures are populated with these callback routines
as part of hpci_attach() in CFG_ADD.
See
``Critical code section'' in HDK Technical Reference.
Context and synchronization
Interrupt
context
Hardware applicability
All
Version applicability
hpci:
1
References
hpci_attach(D3hpci),
hpci_hpcd_t(D4hpci)
``Hotplug devices'' in HDK Technical Reference
19 June 2005
© 2005 The SCO Group, Inc. All rights reserved.
OpenServer 6 and UnixWare (SVR5) HDK - June 2005