patch-2.4.19 linux-2.4.19/drivers/block/cciss_scsi.h

Next file: linux-2.4.19/drivers/block/cpqarray.c
Previous file: linux-2.4.19/drivers/block/cciss_scsi.c
Back to the patch index
Back to the overall index

diff -urN linux-2.4.18/drivers/block/cciss_scsi.h linux-2.4.19/drivers/block/cciss_scsi.h
@@ -0,0 +1,99 @@
+/*
+ *    Disk Array driver for Compaq SA53xx Controllers, SCSI Tape module
+ *    Copyright 2001 Compaq Computer Corporation
+ *
+ *    This program is free software; you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation; either version 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *    NON INFRINGEMENT.  See the GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program; if not, write to the Free Software
+ *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ *    Questions/Comments/Bugfixes to arrays@compaq.com
+ *
+ */
+#ifdef CONFIG_CISS_SCSI_TAPE
+#ifndef _CCISS_SCSI_H_
+#define _CCISS_SCSI_H_
+
+#include <scsi/scsicam.h> /* possibly irrelevant, since we don't show disks */
+
+		// the scsi id of the adapter...
+#define SELF_SCSI_ID -1 
+		// In case we ever want to present controller so sg will 
+		// bind to it.  The scsi bus that's presented by the
+		// driver to the OS is fabricated.  The "real" scsi-3
+		// bus the hardware presents is fabricated too.
+		// The actual, honest-to-goodness physical
+		// bus that the devices are attached to is not
+		// addressible natively, and may in fact turn
+		// out to be not scsi at all.
+
+#define SCSI_CCISS_CAN_QUEUE 2
+
+/* this notation works fine for static initializations (as is the usual
+   case for linux scsi drivers), but not so well for dynamic settings,
+   so, if you change this, you also have to change cciss_unregister_scsi()
+   in cciss_scsi.c  */
+#define CCISS_SCSI {    \
+	name:			"",				\
+	detect:			cciss_scsi_detect,		\
+	release:		cciss_scsi_release,		\
+	proc_info:		cciss_scsi_proc_info,		\
+	queuecommand:   	cciss_scsi_queue_command,	\
+	bios_param:     	scsicam_bios_param,		\
+	can_queue:      	SCSI_CCISS_CAN_QUEUE,		\
+	this_id:		SELF_SCSI_ID,			\
+	sg_tablesize:   	MAXSGENTRIES, 			\
+	cmd_per_lun:		1,				\
+	use_new_eh_code:	1,				\
+	use_clustering:		DISABLE_CLUSTERING,\
+}
+
+/*
+	info:			cciss_scsi_info,		\
+
+Note, cmd_per_lun could give us some trouble, so I'm setting it very low.
+Likewise, SCSI_CCISS_CAN_QUEUE is set very conservatively.
+
+If the upper scsi layer tries to track how many commands we have
+outstanding, it will be operating under the misapprehension that it is
+the only one sending us requests.  We also have the block interface,
+which is where most requests must surely come from, so the upper layer's
+notion of how many requests we have outstanding will be wrong most or
+all of the time.
+
+Note, the normal SCSI mid-layer error handling doesn't work well
+for this driver because 1) it takes the io_request_lock before
+calling error handlers and uses a local variable to store flags,
+so the io_request_lock cannot be released and interrupts enabled
+inside the error handlers, and, the error handlers cannot poll
+for command completion because they might get commands from the
+block half of the driver completing, and not know what to do
+with them.  That's what we get for making a hybrid scsi/block
+driver, I suppose.
+
+*/
+
+struct cciss_scsi_dev_t {
+	int devtype;
+	int bus, target, lun;		/* as presented to the OS */
+	unsigned char scsi3addr[8];	/* as presented to the HW */
+};
+
+struct cciss_scsi_hba_t {
+	char *name;
+	int ndevices;
+#define CCISS_MAX_SCSI_DEVS_PER_HBA 16
+	struct cciss_scsi_dev_t dev[CCISS_MAX_SCSI_DEVS_PER_HBA];
+};
+
+#endif /* _CCISS_SCSI_H_ */
+#endif /* CONFIG_CISS_SCSI_TAPE */

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)