msi_lpmaint.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef	lint
static char *sccsid = "@(#)msi_lpmaint.c	4.1	(ULTRIX)	7/2/90";
#endif	lint

/************************************************************************
 *                                                                      *
 *                      Copyright (c) 1989                              *
 *              Digital Equipment Corporation, Maynard, MA              *
 *                      All rights reserved.                            *
 *                                                                      *
 *   This software is furnished under a license and may be used and     *
 *   copied  only  in accordance with the terms of such license and     *
 *   with the  inclusion  of  the  above  copyright  notice.   This     *
 *   software  or  any  other copies thereof may not be provided or     *
 *   otherwise made available to any other person.  No title to and     *
 *   ownership of the software is hereby transferred.                   *
 *                                                                      *
 *   The information in this software is subject to change  without     *
 *   notice  and should not be construed as a commitment by Digital     *
 *   Equipment Corporation.                                             *
 *                                                                      *
 *   Digital assumes no responsibility for the use  or  reliability     *
 *   of its software on equipment which is not supplied by Digital.     *
 *                                                                      *
 ************************************************************************
 *
 *
 *   Facility:	Systems Communication Architecture
 *		Mayfair Storage Interconnect Port Driver
 *
 *   Abstract:	This module contains Mayfair Storage Interconnect Port
 *		Driver( MSI ) local port maintenance service functions.
 *
 *   Creator:   Todd M. Katz    Creation Date:  December 17, 1988
 *
 *   Function/Routines:
 *
 *   msi_crash_lport		Crash Local MSI Port
 *   msi_remote_rst		Reset Remote Port and System
 *   msi_remote_strt		Start Remote Port and System
 *   msi_shutdown		Inform Known Systems of Local Shutdown
 *
 *   Modification History:
 *
 *   14-Jun-1989	Pete Keilty
 *	Add include file smp_lock.h
 */

/* Libraries and Include Files.
 */
#include		"../h/types.h"
#include		"../h/param.h"
#include		"../h/time.h"
#include		"../h/kmalloc.h"
#include		"../h/ksched.h"
#include		"../h/errlog.h"
#include		"../h/smp_lock.h"
#ifdef mips
#include		"../h/systm.h"
#include		"../h/vmmac.h"
#endif
#include		"../io/scs/sca.h"
#include		"../io/scs/scaparam.h"
#include		"../io/ci/cippdsysap.h"
#include		"../io/ci/cisysap.h"
#include		"../io/msi/msisysap.h"
#include		"../io/bi/bvpsysap.h"
#include		"../io/gvp/gvpsysap.h"
#include		"../io/uba/uqsysap.h"
#include		"../io/sysap/sysap.h"
#include		"../io/ci/cippdscs.h"
#include		"../io/ci/ciscs.h"
#include		"../io/msi/msiscs.h"
#include		"../io/bi/bvpscs.h"
#include		"../io/gvp/gvpscs.h"
#include		"../io/uba/uqscs.h"
#include		"../io/scs/scs.h"
#include		"../io/ci/cippd.h"
#include		"../io/msi/msiport.h"

/* External Variables and Routines.
 */
extern	PB		*cippd_get_pb();
extern	u_short		msi_lpc_panic;
extern	MSIB		*msi_alloc_pkt();
extern	void		msi_clean_port(),
			msi_dealloc_pkt(),
			msi_disable(),
			msi_log_devattn(),
			msi_log_packet(),
			msi_xfp();

/*   Name:	msi_crash_lport	- Crash MSI Local Port
 *
 *   Abstract:	This routine crashes a specific local MSI port and initiates
 *		the process by which it is disabled, cleaned up, and
 *		re-initialized.  It may be sequentially invoked any number of
 *		times to crash a specific port; however, only its first
 *		invocation actually results in crashing of the port.  All
 *		subsequent invocations only log crash requests.  This situation
 *		persists until after the next incarnation of the port begins
 *		following completion of port clean up and re-initialization.
 *
 *		NOTE: This routine may NEVER be invoked with the address of the
 *		      SCS header in an optional MSIB buffer.  The CI PPD
 *		      currently never makes use of this routine parameter and
 *		      the MSI port driver caches the address, size, and remote
 *		      port station address of any optional MSI packet it wishes
 *		      logged.
 *
 *		NOTE: All error recovery is bypassed in favor of immediately
 *		      panicing the system whenever the MSI configuration
 *		      variable flag msi_lpc_panic is set.  Normally, this flag
 *		      is 0 and error recovery is the default action taken.  It
 *		      is set only when special debugging activity is required.
 *
 *		NOTE: The MSI port driver NEVER requires sanity checks to be
 *		      made on its local ports.  It always initializes the PCCB
 *		      specific finite state machine status bit "nosanity_chk"
 *		      so that the CI PPD skips such checks.  Therefore, the CI
 *		      PPD must NEVER to invoke this routine to crash a local
 *		      MSI port because of a failed sanity check( reason ==
 *		      SE_PPDSANITY ).
 *
 *   Inputs:
 *
 *   IPL_SCS			- Interrupt processor level
 *   msi_lpc_panic		- MSI local port crash panic flag
 *   pccb			- Port Command and Control Block pointer
 *	pd.msi			-  MSI specific PCCB fields
 *	    lpcinfo		-   Optional local port crash information
 *		pkth		-    Address of MSI packet
 *		pktsize		-    Size of msi packet
 *		pport_addr	-    Packet remote port station address
 *	    lpstatus.optlpcinfo -   Optional local port crash information flag
 *	    save_dssr		-   Cached DSSI status register contents
 *	    save_dstat		-   Cached data transfer status reg contents
 *   reason			- Reason for crashing local MSI port
 *   scsbp			- NULL !!!!
 *
 *   Outputs:
 *
 *   IPL_SCS			- Interrupt processor level
 *   pccb			- Port Command and Control Block pointer
 *	forkb			-  PCCB fork block
 *	lpinfo.reason		-  Reason for port failure
 *	pd.msi			-  MSI specific PCCB fields
 *	    errlogopt.portnum	-   Remote port station address
 *	ppd.cippd		-  CI PPD specific PCCB fields
 *	    fsmstatus.cleanup	-   1
 *	    fsmstatus.fkip	-   1
 *	    fsmstatus.online	-   0
 *
 *   SMP:	The PCCB is locked INTERNALLY whenever it was not locked
 *		EXTERNALLY prior to routine invocation.  Locking the PCCB
 *		allows exclusive access to PCCB contents, prevents PB deletion,
 *		and is required by both msi_log_packet() and msi_log_devattn(),
 *		the routines responsible for logging local port crash requests.
 *		PCCB addresses are always valid because these data structures
 *		are never deleted once their corresponding ports have been
 *		initialized.
 *
 *   		The PCCB specific XFP and RFP are locked INTERNALLY whenever
 *		they were not locked EXTERNALLY prior to routine invocation.
 *		Their locking is required by msi_disable(), the routine
 *		responsible for disabling the local MSI port.
 *
 *		The PCCB specific XFP and RFP are not only locked but the
 *		respective fork processes are synchronized to as well.  This
 *		synchronization is necessary because occassions exist when
 *		active fork processes must protect against crashing of the
 *		local port while temporarily releasing their locks.
 *		Synchronization to the fork processes by means of their
 *		in-progress SIIBUF pointers is the mechanism chosen to provide
 *		this protection.
 */
void
msi_crash_lport( pccb, reason, scsbp )
    register PCCB	*pccb;
    register u_long	reason;
    SCSH		*scsbp;
{
    register PB		*pb;
    u_long		unlock_pccb,
			unlock_rfp,
			unlock_xfp;

    /* Crashing a local MSI port consists of a number of distinct steps:
     *
     * 1. The crash request is pre-processed.
     * 2. The local port is disabled.
     * 3. The local port is cleaned up.
     * 4. The local port is re-initialized.
     *
     * The first step is executed each time this routine is invoked.  It is the
     * latter three steps which constitute crashing the port and are executed
     * only once per port incarnation.  The major benefits of this single 
     * threading of port crashing are the assumptions made during port clean up
     * and re-initialization which follow directly from it.  These assumptions
     * greatly reduce code complexity and allow extension of the MSI port
     * driver to an SMP environment with a minimum of pain.  They are pointed
     * out as they occur.
     *
     * Pre-processing of crash requests includes:
     *
     * 1. Locking the PCCB whenever it was not locked EXTERNALLY.
     * 2. Retrieving the appropriate PB whenever an optional MSI packet was
     *	  cached within the PCCB.
     * 3. Applying the local port crash severity modifier( ESM_LPC ) to the
     *    local port crash reason code.
     * 4. Logging the crash request according to the provided crash reason.
     * 5. Optionally panicing the system.
     *
     * The presence of an optional MSI packet is indicated by the status of the
     * "optlpcinfo" local port status flag.  This flag is set when optional
     * local port crash information is cached within the PCCB, cleared
     * otherwise.
     *
     * The local port crash severity modifier is applied( Step 3 ) ONLY if the
     * local port is not already in the process of being crashed.  
     *
     * Panicing of the system( Step 5 ) immediately terminates all further
     * processing of the crash request.  Such panicing is OPTIONAL.  It is
     * requested only when the MSI configuration variable flag msi_lpc_panic is
     * set.  This flag is set only when special debugging activity is required.
     *
     * Following pre-processing this routine ascertains whether or not the port
     * has already been crashed but not yet re-initialized.  If this is indeed
     * the case, as indicated by a PCCB clean up in progress status flag, then
     * the current request is dismissed after the PCCB is unlocked( provided it
     * was unlocked within this routine ).  Otherwise, actual crashing of the
     * port commences with disablement of the local port including:
     *
     * 1. Setting the port clean up in progress flag to prohibit additional
     *    crashings of the port until it has been re-initialized.
     * 2. Taking the port offline.
     * 3. Locking the PCCB specific RFP and XFP.
     * 4. Synchronizing to any active Transmit and Receive Fork Processes.
     * 5. Flushing the SIIBUF transmit-in-progress circular queue by
     *	  deallocating all associated MSIB packets.
     * 6. Resetting the SII chip.
     * 7. Marking the local MSI port inactive.
     * 8. Unlocking the PCCB specific RFP and XFP.
     *
     * The first five steps of local port disablement( Steps 1-5 ) and Step 8
     * are executed by this routine.  The remaining two steps( Steps 6-7 ) are
     * accomplished through invocation of msi_disable(), the routine
     * responsible for disabling local MSI ports.