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-rw-r--r--drivers/block/cciss_scsi.h79
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diff --git a/drivers/block/cciss_scsi.h b/drivers/block/cciss_scsi.h
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+/*
+ * 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 iss_storagedev@hp.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 15
+ // 15 is somewhat arbitrary, since the scsi-2 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
+
+/*
+
+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 */