scsi.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

#ifndef lint
static  char    *sccsid = "@(#)scsi.c	4.11  (ULTRIX)        2/14/91";
#endif lint

/************************************************************************
 *									*
 *			Copyright (c) 1988 by				*
 *		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.	*
 *									*
 ************************************************************************/

/************************************************************************
 *
 * scsi.c	12/19/89
 *
 * CVAX/FIREFOXstar/PVAX/PMAX SCSI device driver (common code)
 *
 * Modification history:
 *
 *   29-Jan-91	Robin Miller
 *	o  Added support for CD-ROM audio commands.
 *	o  Moved pseudo SCSI commands to group 3 range (0x60-0x7f)
 *	   to avoid conflict with CD-ROM audio commands.
 *
 *   09-Jan-91	Robin Miller
 *	On fixed length block tapes (QIC), if the byte count isn't modulo
 *	the block size, return the error code EINVAL ("invalid argument")
 *	instead of ENXIO ("no such device or address") to avoid confusion.
 *	This error occurs frequently when using the 'dd' utility if the
 *	'sync=conv' option is omitted to pad output records.
 *
 *   27-Nov-90	Robin Miller
 *	Merged in Bill Dallas fix which resets the szflags field before
 *	retrying the command.  Previously if the device had disconnected
 *	with a check condition, the DMA disconnect flag (SZ_DMA_DISCON)
 *	was left set causing the wrong DMA count to be setup which later
 *	panic'ed the system.
 *
 *   26-Nov-90	Robin Miller
 *	o  Added function sz_cdb_length() to calculate and return the
 *	   Command Descriptor Block length.  The length is calculated
 *	   using the group code of the command.
 *	o  Removed '#ifdef FORMAT' conditionalization, since the special
 *	   interface is used to implement CD-ROM Audio commands.
 *	o  Added support for 10-byte read/write CDB's.  If the LBA is
 *	   too large for 6-byte CDB, setup and send a 10-byte CDB.
 *
 *   07-Nov-90	Robin Miller
 *	Changed logic associated with checking of End Of Media (EOM) and
 *	File Mark (FM) bits in the sense data for the TLZ04 (RDAT).  The
 *	RDAT sets both of these bits on reads past LEOT (early warning).
 *	Previously, we only checked and returned EOM status and ignored
 *	the FM bit.  This broke the restore utility since it expected an
 *	end of file indication (FM returns count of 0) to prompt for the
 *	next volume.
 *
 *   26-Oct-90	Robin Miller
 *	Modified scsi_logerr() function to pickup the proper controller
 *	base address out of the softc structure.  Previously, it was
 *	always using the base address of the first SCSI controller.
 *
 * 21-Sept-90	Bill Dallas
 *	Added fixes for correct handling of flags for tapes. This
 *	includes tpmark, dev_cse, and dev_shrtrec. All fixes are
 * 	in the state machine (state SZ_BEGIN). Please see the 
 *	comments in the code for a complete description.
 * 
 *   10-Sep-90  Charles Richmond IIS Corp
 *	Added declarations required for kzqsa board and driver.
 *
 *   24-Aug-90  Maria Vella
 *      - Set the sc_category_flags field with DEV_SHRTREC when ILI bit
 *        set in Request Sense data.  Used to be set in sc_flags which
 *        was interpreted as DEV_EOM in tape driver.
 *
 *   15-Aug-89	Robin Miller
 *	o  Added errlog cases for RRD42, RX26, and RZ25 devices.
 *
 *	o  Modified the szerror() routine so "Device Not Ready" errors
 *	   get sent to the error logger.  This error logging is only
 *	   done if the current command isn't a Test Unit Ready (SZ_TUR)
 *	   so checks in device open routines don't get logged as errors.
 *	   Previously ejecting a tape or a CD during an command didn't
 *	   get logged, only EIO was returned to the program.
 *
 *	o  Fixed problem logging errors for CD-ROM devices.  The
 *	   scsi_logerr() routine was not checking for CD-ROM devices
 *	   when setting up the class type field, so it was set to
 *	   undefined (EL_UNDEF).  The 'uerf' utility would then report
 *	   "OS EVENT TYPE 65535" and not display the error information.
 *	   The CD-ROM errors are now treated the same as disk errors.
 *
 *   10-Aug-90  Maria Vella
 *      - Cleared the SZ_NEED_SENSE bit in sc_szflags for: 
 *          - SP_START in the default case on return from sc->port_start()
 *          - SP_START_ERR after call to sz_restore_rqsns().
 *      - Added call to sz_restore_rqsns() in SZ_W_DMA in the
 *        default case on return from sc->port_start().
 *      
 *   30-Jul-90 	Bill Dallas   
 *	Added fixed block tape units tape mark handling.
 *	This included a new falg in sc_category_flags called
 *	TPMARK_PENDING
 *
 *   16-Jul-90  Janet Schank
 *	Added errlog cases for the RZ23L.
 *
 *   25-Jun-90	 Mitchell McConnell
 *	o  Fix for PMAX - port_start for RQSNS will return BUSBUSY if
 *	   unable to select due to reselection.  In this case, instead
 *	   of the event remaining the same, we need to set the event to
 *	   SZ_SELRETRY_SNS to work with state machine changes for 3max
 *	   (see explanation for 13-Jun-90).
 *
 *   13-Jun-90	 Mitchell McConnell
 *	o  Fix for RDAT "dropped packets" problem.  The port_start for 
 *	   RQSNS was returning SZ_IP, but we then lost arbitration (which
 *	   we didn't find out till interrupt time).  The problem is how to
 *	   recover state in a sufficiently general way without having
 *	   to create more sub-states, etc.  The proposed solution is to
 *	   use the pxstate field in the softc (this is how it is used by
 *	   the vax) which will be the state to return to if the select 
 *	   fails.  In the "normal" case, the oops state will be SZ_NEXT/BEGIN,
 *	   just as it has always been.  For the special RQSNS states,
 *	   the new state must revert "back" one state, i.e., SZ_RDMA_ERR
 *	   must go back to SZ_R_DMA.  The catch is that any flags that
 *	   may have been altered must be set back to their original values.
 *	   E.g., the routines save_rqsns and restore_rqsns must be called
 *	   so that on the next iteration through SZ_R_DMA, the NEED_SENSE
 *	   flag will be set, and the RQSNS may be retried.
 *
 *   07-Jun-90 	 Mitchell McConnell
 *	o  Reverted change of 20-Jan-90 back to original scheme to try
 *	   and isolate RDAT problem.
 *
 *   06-June-90	Bill Dallas
 *	Added support for the option table... new field in the devtab struct.
 *	This will allow easy additions of devices of a known type..tape/disk
 *
 *   17-May-90  John A. Gallant
 *	Added setting BERROR in the error leg of the SM.
 *
 *   16-May-90   Mitchell McConnell
 *	o  Removed ifdef'ed FORMAT stuff.
 *	o  Added new error states to handle SZ_IP return code from 
 *	   RQSNS.  All of the main states now have a box before their
 *	   case statement, to help in following the code.
 *	o  Because of asynchronous nature of RQSNS, must save relevant
 *	   softc fields on a per-target basis.  Created new structure
 *	   and routines to save/restore...
 *
 *   19-Mar-90  Janet Schank
 *      Added errlog cases for RZ24, RZ57, and TZ05.
 *
 *   26-FEB-90  Janet Schank
 *      Added errlog case for TLZ04 (RDAT).
 *
 * 23-Feb-90 -- sekhar
 *      Merged Joe Martin's fix for 3.1 cld. When copying user PTEs,
 *      check for page crossing and reevaluate vtopte.
 *
 *   20-Jan-90  Mitchell McConnell
 *	DEV_TPMARK and DEV_SHRTREC were previously set in category_flags
 *	to indicate filemark and over-read, respectively.  DEV_TPMARK was
 *	doing double duty, however, since it remained set until cleared by
 *	another tzopen or clear serious exception.  What is needed are 2
 *	flags which apply only to the current i/o to know how to handle
 *	residual bytes (in ST_R_DMA).  Since sc_flags is elsewhere used
 *	in this way, we now set TPMARK (when it occurs) in both sc_flags 
 *	and sc_category flags, with sc_flags being cleared as soon as 
 *	sc_resid is set.  Similarly, we now use sc_flags for SHRTREC 
 *	instead of category flags.
 *
 *   19-Dec-89	John A. Gallant
 *	Restored the error retry code in the szerror() routine, and in the SM
 *	now compare the retries aginst the SP/RW_RTCNT defines in scsireg.h
 *
 *   11-Dec-89  Mitchell McConnell
 *	Set sc_attached flag in szattach() to catch problem where devices
 *	which were physically present and alive but not configured were
 *	causing the system to hang.
 *
 *   11-Nov-89  Mitchell McConnell
 *      Added ASC support to scsi_logerr.  Added ASC logerr string 
 *      to sz_BusErr array entry #5. Made entry for 4C non-SII 
 *      specific, since I need to share it and the context
 *	should be clear from the controller id.
 *
 *   17-Oct-89  Janet L. Schank / JAG
 *      The RDAT drive was setting both the filemark and ili bits 
 *      in the request sense data when a filemark is read.  Changed
 *      the checks for these bits in szerror to only set one error
 *      flag depending on these bits.  Added the function get_scsiid.
 *
 *   17-Oct-89  Janet L. Schank / Art Zemon
 *      Added TZ05 support
 *
 *   04-Oct-89	Fred Canter
 *	Bug fix. Added newline to resetting SCSI bus message.
 *	Added sector number to error log packet for disk errors.
 *	Use sz_sbtol() to extract infobytes from sense data.
 *
 * 10/12/89     Janet L. Schank
 *      Moved the clearing of the rambuff from scsi.c to sii_scsistart
 *
 * 09/22/89     Janet L. Schank
 *      Changed some defines and ifdefs to include and use sii.h.
 *      Removed many "ifdef vax"'s.  Added default scsi_devtab
 *      entries:  szp_rz_udt, szp_tz_udt, szp_cz_udt.  Added sz_devname
 *      and sz_revlevel arrays.  Replaced the szattach and szslave
 *      functions with "auto-config" versions from the vax-side code.
 *
 *   14-Aug-89	Fred Canter
 *	Enabled binary error logging (sz_log_errors = 1).
 *	Bug fix: not setting registers valid flag for SII.
 *
 *   25-Jul-89	Fred Canter
 *	Separate SCSI device name defines from MSCP/TMSCP names.
 *
 *   23-Jul-89	Fred Canter
 *	Convert DBBR printfs to error log calls.
 *	RX33 support.
 *
 *   22-Jul-89	Fred Canter
 *	Always log "resetting bus" to console.
 *
 *   16-Jul-89	Fred Canter
 *	Do mode sense to get disk geometry.
 *
 *   15-Jul-89	Fred Canter
 *	Merged Dynamic BBR and error log changes.
 *	Add flag to control logging of DATAPROTECT errors (sz_log_we_errors).
 *
 *
 *   13-Jul-89	Fred Canter
 *	Special mode select/sense handling for the EXABYTE tape.
 *
 *   12-Jul-89	Fred Canter
 *	Added scsi_logerr() routine for SCSI binary error logging.
 *	Save current CDB and status byte for error log.
 *
 *	Buf gix (same as stc.c). Back/forward space thru a file mark
 *	should fail but wasn't.
 *
 *   27-Jun-89	John A. Gallant
 *	Moved the completion handling of a bp, from the statemachine to the
 *	completion handler for the drivers.  Included support for the read/
 *	write long commands.
 *
 *   14-Jun-89	Fred Canter
 *	Initialize sc_c_status in sz_start(), caused rzspecial commands
 *	to fail because of left over bad status.
 *
 *   11-Jun-89	Fred Canter
 *	Save additional sense code in sz_softc so we can tell when the
 *	floppy media has been changed. Hooks for softpc.
 *
 *   24-May-89	Fred Canter
 *	Changes to match the new, more general rzdisk utility.
 *	Changed the mode select data structures so an address and
 *	length are passed with the ioctl. This allows pages to be
 *	added to rzdisk without requiring a kernel rebuild.
 *
 *   22-May-89	Fred Canter
 *	Fixed a bug in the code which copies the data back to the user
 *	on a unrecoverable data error. The code was completely wrong and
 *	would cause a panic on a medium error (such as reading a unformatted
 *	SCSI floppy).
 *
 * 03/30/89	John A. Gallant
 *	Pulled more fixed from the VAX side for rxdisk:
 *	Fixed an "rzdisk" related bug. If an "rzdisk" command gets
 *	a check condition an the sense key is SZ_NOSENSE then return
 *	good status.
 *	Modified the state machine to copy data back to the user
 *	on UNRECOVERABLE data errors. The data copied back to the
 *	user consists of the data starting from the beginning of
 *	the disk transfer upto and including the bad block. This
 *	is needed mainly for "rzdisk" when REASSIGNING bad blocks.
 *
 * 03/22/89	John A. Gallant
 *	In sz_bldpkt() for mode select, if the tape is a TZxx don't send
 *	any of the vender unique bits.  Set the pll field to 12.
 *
 * 03/01/89	John A. Gallant
 *	Added the pseudo command codes for to allow the tape to unload.  I
 *	followed the same conventions as the firefox/pvax code.
 *
 * 01/16/89	John A. Gallant
 *	More modifications from the firefox/pvax code:
 *	Call szerror() for certain tzcommands so the reason they
 *	failed gets entered into the error log.
 *	If BBWAIT is set, the b_command/b_resid field is not copied to curcmd.
 *	I also found the "black hole".
 *
 * 12/14/88	John A. Gallant
 *	More additions from the firefox code:
 *	Set the "pf" bit when you issue a MODE SELECT to the CDROM.
 *	Needed so "rzdisk" will work.
 *	Added the printing of the sector number and partition to the
 *	error logger for RECOVERABLE and UNRECOVERABLE data errors.
 *	
 * 12/01/88	John A. Gallant
 *	Fixed the tape ILI, bug, an "over-read" is now flaged in category_flags
 *	for the state machine to check for.
 *
 * 11/23/88	John A. Gallant
 *	Revamped the debug printfs, to allow tracking of single targets.
 *
 * 11/09/88	John A. Gallant
 *	Started the merge with the V3.0 source level.  Due to time constraints
 *	only the changes for the new IOCTL support will be merged.  Others
 *	changes will hopefully occur as time permits.  Copied over the timeout
 *	table, however, it is not implemented.
 *   COMMENTS from V3.0:
 *   03-Nov-88	Alan Frechette
 *	Added in support for disk maintainence. Added the commands
 *	FORMAT UNIT, REASSIGN BLOCK, READ DEFECT DATA and VERIFY DATA.
 *	Made changes to MODE SENSE and MODE SELECT. Figured out a better
 *	way to determine length of a SCSI command in "sz_bldpkt()".
 *
 * 11/07/88	John A. Gallant
 *	All changes are removal of target 5 debug statements.  Added a debug
 *	statement for each interation of the statemachine.
 *
 *   10-Oct-88	 Ricky Palmer (rsp)
 *	One last pass through here for FT1.
 *
 *   16-Sep-88	 Ricky Palmer (rsp)
 *	Fixed rz23 support.
 *
 *   14-Sep-88	 Ricky Palmer (rsp)
 *	Added IS_KUSEG macro test to mapping code.
 *	Also put in panic for bad addr if mapping is to user space.
 *
 *    7-Sep-88	 Ricky Palmer (rsp)
 *	Added new code and support for PMAX. There are changes 
 *	in the probe and setup code as well as the start routine
 *	in order to support the scsi_sii.c routines. The changes
 *	are surrounded by ifdef's where necessary.
 *
 *   25-Aug-88   Ricky Palmer
 *      Ifdef'ed again for vax and mips. This time it is based on
 *      my August 1, 1988 ifdef's of the original scsi.c "glob" driver.
 *
 *   18-Aug-88 -- Fred Canter
 *	Pass -1 not 0 to sz_start() to start next I/O (fix target ID 0).
 *	Add sz_em_print to control extended message debug printout.
 *	Fix driver not always seeing MICROPOLIS B drive by asserting
 *	ATTN before droping ACK on last byte of extended message.
 *	Add SHMEM code to bcopy (pte mapping) to fix BAR 435.
 *	Changed select enable back to the original way.
 *	Try interrupt instead of spin on phase change (doesn't work yet).
 *	Fix driver bug which made it think targets were skipping
 *	the status command (sometimes), data in was eating status byte.
 *
 *	Merge PVAX and FIREFOX drivers.
 *
 *   08-Aug-88 -- Alan Frechette
 *	Merged in all of the SII portion of this driver. Modified
 *	the driver to execute the correct code paths whether using
 *	the SII chip or the NCR 5380 chip. Fixed a few bugs in the
 *	SII code, made changes to the SII code based on Fred's new
 *	driver and tried to improve performance.
 *
 *   08-Aug-88 -- Fred Canter
 *	Removed stray interrupt code (can recover from last delta).
 *	In szprobe, reset bus if BSY/SEL wedged after inquiry.
 *	Clean out old debug and hltcod code.
 *	Fix for parity errors caused by PARCK enabled during arbitration.
 *
 *   28-Jul-88 -- Fred Canter
 *	Removed old code which supported RRD40 as device 'cz' (now 'rz).
 *	Fixed background timer to work with 2nd SCSI controller.
 *	Program around TZ30 holding BSY true after command complete.
 *	Added extended message support so driver will work with
 *	yet another version of the RZ55.
 *	Removed ond sz_timer code.
 *	Clean up sz_flags for much improved reselect timeout handling.
 *	Removed old disconnect timeout code from background timer.
 *
 *   18-Jul-88 -- Fred Canter
 *	Removed all #ifdef CZ code (can recover it from last delta).
 *	Fix background timer for 2nd SCSI controller.
 *	Added work around for TZ30 holding bus after command complete.
 *	Fixed MICROPOLIS B RZ55 support (handle extended message).
 *
 *   16-Jul-88 -- Fred Canter
 *	Handle unit attn condition (media change).
 *	Convert sz_active from 0-7 to ID bit position.
 *	Improve reselect timeout handling (CDROM hacks).
 *	Enable parity checking at all times.
 *	Fixed a bug in rzioctl which prevented the driver from
 *	ever setting the default partitions once the disk had
 *	a partition table on it.
 *	Changed the RRD40 name from cz to rz (CDROM is a disk).
 *	Lots of code cleanup.
 *
 *   28-Jun-88 -- Fred Canter
 *	Several driver improvements and code cleanup:
 *		Restructure for better ??command() handling.
 *		Deal with unit attn (TZ cartridge change).
 *		Read system's (initiator) bus ID from NVR.
 *		Fix DEV_WRITTEN flag handling.
 *		Background timer to catch lost interrupts
 *		and reselect timeouts.
 *
 *   18-Jun-88 -- Fred Canter
 *	Added RZ55 support and fixed a bug in partition table code.
 *	Fixed a bug in request sense status which caused intalls to fail.
 *	Improved (but not fixed) lost interrupt and reselect timeout
 *	handling (massive code changes).
 *
 *   07-Jun-88 -- Fred Canter
 *	Bug fixes for finder opening every possible device in the world.
 *
 *   06-Jun-88 -- Fred Canter
 *	First submit to V2.4 pool (sccs create). Much cleanup done.
 *	Much more needed. Driver functioning well enough to support
 *	building a kit for testing.