OSST tape driver fix for 2.5.51

The patch to osst.c below is needed to fix an oops and at the same time
brings in some bug fixes discovered in the 2.4 version.

drivers/scsi/osst.c

@@ -24,7 +24,7 @@
 */
 
 static const char * cvsid = "$Id: osst.c,v 1.65 2001/11/11 20:38:56 riede Exp $";
-const char * osst_version = "0.99.0p3";
+const char * osst_version = "0.99.0p5";
 
 /* The "failure to reconnect" firmware bug */
 #define OSST_FW_NEED_POLL_MIN 10601 /*(107A)*/
@@ -60,7 +60,6 @@ const char * osst_version = "0.99.0p3";
    in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
 #define OSST_DEB_MSG  KERN_NOTICE
 
-
 #include "scsi.h"
 #include "hosts.h"
 #include <scsi/scsi_ioctl.h>
@@ -85,7 +84,7 @@ MODULE_PARM(max_dev, "i");
 MODULE_PARM_DESC(max_dev, "Maximum number of OnStream Tape Drives to attach (4)");
 
 MODULE_PARM(write_threshold_kbs, "i");
-MODULE_PARM_DESC(write_threshold_kbs, "Asynchronous write threshold (KB; 30)");
+MODULE_PARM_DESC(write_threshold_kbs, "Asynchronous write threshold (KB; 32)");
 
 MODULE_PARM(max_sg_segs, "i");
 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (9)");
@@ -170,8 +169,8 @@ struct Scsi_Device_Template osst_template =
 	.attach =       osst_attach,
 	.detach =       osst_detach,
 	.scsi_driverfs_driver = {
-		.name	= "osst",
-	},
+		.name =  "osst",
+	}
 };
 
 static int osst_int_ioctl(OS_Scsi_Tape *STp, Scsi_Request ** aSRpnt, unsigned int cmd_in,unsigned long arg);
@@ -221,7 +220,7 @@ static int osst_chk_result(OS_Scsi_Tape * STp, Scsi_Request * SRpnt)
 		if (scode) printk(OSST_DEB_MSG "%s:D: Sense: %02x, ASC: %02x, ASCQ: %02x\n",
 			       	name, scode, sense[12], sense[13]);
 		if (driver_byte(result) & DRIVER_SENSE)
-			print_req_sense("osst", SRpnt);
+			print_req_sense("osst ", SRpnt);
 	}
 //	else
 #endif
@@ -543,8 +542,6 @@ static int osst_verify_frame(OS_Scsi_Tape * STp, int frame_seq_number, int quiet
 				 STp->first_frame_position);
 		goto err_out;
 	}
-//	STp->frame_in_buffer = 1;
-
         if (frame_seq_number != -1 && ntohl(aux->frame_seq_num) != frame_seq_number) {
 		if (!quiet)
 #if DEBUG
@@ -749,7 +746,7 @@ static int osst_flush_drive_buffer(OS_Scsi_Tape * STp, Scsi_Request ** aSRpnt)
 	Scsi_Request  * SRpnt;
 
 	int             result = 0;
-	int		delay  = OSST_WAIT_LONG_WRITE_COMPLETE;
+	int		delay  = OSST_WAIT_WRITE_COMPLETE;
 #if DEBUG
 	char *name = tape_name(STp);
 
@@ -763,17 +760,14 @@ static int osst_flush_drive_buffer(OS_Scsi_Tape * STp, Scsi_Request ** aSRpnt)
 	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, SCSI_DATA_NONE, STp->timeout, MAX_WRITE_RETRIES, TRUE);
 	*aSRpnt = SRpnt;
 	if (!SRpnt) return (-EBUSY);
-//printk(OSST_DEB_MSG "%s:X: Write filemark returned %x:%02x:%02x:%02x\n",dev,STp->buffer->syscall_result,SRpnt->sr_sense_buffer[2] & 0x0f,SRpnt->sr_sense_buffer[12],SRpnt->sr_sense_buffer[13]);
 	if (STp->buffer->syscall_result) {
 		if ((SRpnt->sr_sense_buffer[2] & 0x0f) == 2 && SRpnt->sr_sense_buffer[12] == 4) {
 			if (SRpnt->sr_sense_buffer[13] == 8) {
-//printk(OSST_DEB_MSG "%s:X: Long initial delay\n", dev);
 				delay = OSST_WAIT_LONG_WRITE_COMPLETE;
 			}
 		} else
 			result = osst_write_error_recovery(STp, aSRpnt, 0);
 	}
-//printk(OSST_DEB_MSG "%s:X: Entering wait ready (%d)\n",dev,delay);
 	result |= osst_wait_ready(STp, aSRpnt, 5 * 60, delay);
 	STp->ps[STp->partition].rw = OS_WRITING_COMPLETE;
 
@@ -1708,12 +1702,7 @@ static int osst_space_over_filemarks_backward(OS_Scsi_Tape * STp, Scsi_Request *
 						 name, last_mark_ppos);
 				return (-EIO);
 			}
-			if (mt_op == MTBSFM) {
-				STp->frame_seq_number++;
-				STp->frame_in_buffer  = 0;
-				STp->logical_blk_num += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
-			}
-			return 0;
+			goto found;
 		}
 #if DEBUG
 		printk(OSST_DEB_MSG "%s:D: Reverting to scan filemark backwards\n", name);
@@ -1741,10 +1730,13 @@ static int osst_space_over_filemarks_backward(OS_Scsi_Tape * STp, Scsi_Request *
 			return (-EIO);
 		}
 	}
+found:
 	if (mt_op == MTBSFM) {
 		STp->frame_seq_number++;
-		STp->frame_in_buffer  = 0;
-		STp->logical_blk_num += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
+		STp->frame_in_buffer      = 0;
+		STp->buffer->buffer_bytes = 0;
+		STp->buffer->read_pointer = 0;
+		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
 	}
 	return 0;
 }
@@ -1797,8 +1789,10 @@ static int osst_space_over_filemarks_forward_slow(OS_Scsi_Tape * STp, Scsi_Reque
 	}
 	if (mt_op == MTFSF) {
 		STp->frame_seq_number++;
-		STp->frame_in_buffer  = 0;
-		STp->logical_blk_num += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
+		STp->frame_in_buffer      = 0;
+		STp->buffer->buffer_bytes = 0;
+		STp->buffer->read_pointer = 0;
+		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
 	}
 	return 0;
 }
@@ -1944,9 +1938,10 @@ static int osst_space_over_filemarks_forward_fast(OS_Scsi_Tape * STp, Scsi_Reque
 	}
 	if (mt_op == MTFSF) {
 		STp->frame_seq_number++;
-		STp->frame_in_buffer  = 0;
+		STp->frame_in_buffer      = 0;
+		STp->buffer->buffer_bytes = 0;
 		STp->buffer->read_pointer = 0;
-		STp->logical_blk_num += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
+		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
 	}
 	return 0;
 }
@@ -3215,8 +3210,8 @@ static ssize_t osst_write(struct file * filp, const char * buf, size_t count, lo
 
 	/* Write must be integral number of blocks */
 	if (STp->block_size != 0 && (count % STp->block_size) != 0) {
-		printk(KERN_ERR "%s:E: Write (%ld bytes) not multiple of tape block size (%d%c).\n",
-				       name, (unsigned long)count, STp->block_size<1024?
+		printk(KERN_ERR "%s:E: Write (%Zd bytes) not multiple of tape block size (%d%c).\n",
+				       name, count, STp->block_size<1024?
 				       STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
 		retval = (-EINVAL);
 		goto out;
@@ -4140,8 +4135,14 @@ static int osst_int_ioctl(OS_Scsi_Tape * STp, Scsi_Request ** aSRpnt, unsigned i
 
 		if (cmd_in == MTEOM)
 			STps->eof = ST_EOD;
-		else if ((cmd_in == MTFSFM || cmd_in == MTBSF) && STps->eof == ST_FM_HIT)
-			ioctl_result = osst_seek_logical_blk(STp, &SRpnt, STp->logical_blk_num - 1);
+		else if ((cmd_in == MTFSFM || cmd_in == MTBSF) && STps->eof == ST_FM_HIT) {
+			ioctl_result = osst_seek_logical_blk(STp, &SRpnt, STp->logical_blk_num-1);
+			STps->drv_block++;
+			STp->logical_blk_num++;
+			STp->frame_seq_number++;
+			STp->frame_in_buffer = 0;
+			STp->buffer->read_pointer = 0;
+		}
 		else if (cmd_in == MTFSF)
 			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_FM;
 		else if (chg_eof)
@@ -4233,8 +4234,7 @@ static int os_scsi_tape_open(struct inode * inode, struct file * filp)
 #endif
 		return (-EBUSY);
 	}
-
-	if (!scsi_device_get(STp->device)) {
+	if (scsi_device_get(STp->device)) {
 		write_unlock(&os_scsi_tapes_lock);
 #if DEBUG
                 printk(OSST_DEB_MSG "%s:D: Failed scsi_device_get.\n", name);
@@ -4856,12 +4856,6 @@ static int osst_ioctl(struct inode * inode,struct file * file,
 		}
 
 		if (mtc.mt_op == MTSETPART) {
-/*     if (!STp->can_partitions ||
-	   mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS)
-	 return (-EINVAL);
-		 if (mtc.mt_count >= STp->nbr_partitions &&
-	   (STp->nbr_partitions = nbr_partitions(inode)) < 0)
-	 return (-EIO);*/
 			if (mtc.mt_count >= STp->nbr_partitions)
 				retval = -EINVAL;
 			else {
@@ -4909,10 +4903,6 @@ static int osst_ioctl(struct inode * inode,struct file * file,
 			goto out;
 		}
 			
-/*   if (STp->can_partitions && STp->ready == ST_READY &&
-	 (i = update_partition(inode)) < 0)
-		 {retval=i;goto out;}*/
-
 		if (mtc.mt_op == MTCOMPRESSION)
 			retval = -EINVAL /*osst_compression(STp, (mtc.mt_count & 1))*/;
 		else
@@ -4931,10 +4921,6 @@ static int osst_ioctl(struct inode * inode,struct file * file,
 		goto out;
 	}
 
-/* if (STp->can_partitions &&
-		 (i = update_partition(inode)) < 0)
-	 {retval=i;goto out;}*/
-
 	if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
 		struct mtget mt_status;
 
@@ -5110,9 +5096,7 @@ static int enlarge_buffer(OSST_buffer *STbuffer, int need_dma)
 	for (segs=STbuffer->sg_segs=1, got=b_size;
 	     segs < max_segs && got < OS_FRAME_SIZE; ) {
 		STbuffer->sg[segs].page =
-			(OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ?
-				kmalloc(OS_FRAME_SIZE - got, priority):
-				alloc_pages(priority, order);
+				alloc_pages(priority, (OS_FRAME_SIZE - got <= PAGE_SIZE) ? 0 : order);
 		STbuffer->sg[segs].offset = 0;
 		if (STbuffer->sg[segs].page == NULL) {
 			if (OS_FRAME_SIZE - got <= (max_segs - segs) * b_size / 2 && order) {
@@ -5320,10 +5304,8 @@ static void validate_options (void)
   if (max_sg_segs >= OSST_FIRST_SG)
 		osst_max_sg_segs = max_sg_segs;
 #if DEBUG
-  printk(OSST_DEB_MSG "osst :D: max tapes %d, write threshold %d, s/g segs %d.\n",
+  printk(OSST_DEB_MSG "osst :D: max tapes %d, write threshold %d, max s/g segs %d.\n",
 			   osst_max_dev, osst_write_threshold, osst_max_sg_segs);
-//printk(OSST_DEB_MSG "osst :D: sizeof(header) = %d (%s)\n",
-//		sizeof(os_header_t),sizeof(os_header_t)==OS_DATA_SIZE?"ok":"error");
 #endif
 }
 	
@@ -5446,7 +5428,7 @@ static int osst_attach(Scsi_Device * SDp)
 	drive = alloc_disk(1);
 	if (!drive) {
 		printk(KERN_ERR "osst :E: Out of memory. Device not attached.\n");
-		return 1;
+		goto out_slave_detach;
 	}
 
 	/* if this is the first attach, build the infrastructure */
@@ -5458,7 +5440,7 @@ static int osst_attach(Scsi_Device * SDp)
 		if (os_scsi_tapes == NULL) {
 			write_unlock(&os_scsi_tapes_lock);
 			printk(KERN_ERR "osst :E: Unable to allocate array for OnStream SCSI tapes.\n");
-			return 1;
+			goto out_put_disk;
 		}
 		for (i=0; i < osst_max_dev; ++i) os_scsi_tapes[i] = NULL;
 	}
@@ -5466,8 +5448,7 @@ static int osst_attach(Scsi_Device * SDp)
 	if (osst_nr_dev >= osst_max_dev) {
 		write_unlock(&os_scsi_tapes_lock);
 		printk(KERN_ERR "osst :E: Too many tape devices (max. %d).\n", osst_max_dev);
-		put_disk(drive);
-		return 1;
+		goto out_put_disk;
 	}
 
 	/* find a free minor number */
@@ -5480,9 +5461,7 @@ static int osst_attach(Scsi_Device * SDp)
 	if (tpnt == NULL) {
 		write_unlock(&os_scsi_tapes_lock);
 		printk(KERN_ERR "osst :E: Can't allocate device descriptor, device not attached.\n");
-		put_disk(drive);
-		scsi_slave_detach(SDp);
-		return 1;
+		goto out_put_disk;
 	}
 	memset(tpnt, 0, sizeof(OS_Scsi_Tape));
 
@@ -5495,9 +5474,7 @@ static int osst_attach(Scsi_Device * SDp)
 		write_unlock(&os_scsi_tapes_lock);
 		printk(KERN_ERR "osst :E: Unable to allocate a tape buffer, device not attached.\n");
 		kfree(tpnt);
-		put_disk(drive);
-		scsi_slave_detach(SDp);
-		return 1;
+		goto out_put_disk;
 	}
 	os_scsi_tapes[dev_num] = tpnt;
 	tpnt->buffer = buffer;
@@ -5623,6 +5600,12 @@ static int osst_attach(Scsi_Device * SDp)
 		SDp->model, SDp->host->host_no, SDp->channel, SDp->id, SDp->lun, tape_name(tpnt));
 
 	return 0;
+
+out_put_disk:
+        put_disk(drive);
+out_slave_detach:
+        scsi_slave_detach(SDp);
+        return 1;
 };
 
 static void osst_detach(Scsi_Device * SDp)
@@ -5630,48 +5613,46 @@ static void osst_detach(Scsi_Device * SDp)
   OS_Scsi_Tape * tpnt;
   int i, mode;
 
+  if ((SDp->type != TYPE_TAPE) || (osst_nr_dev <= 0))
+	  return;
+
   write_lock(&os_scsi_tapes_lock);
-  if (os_scsi_tapes != NULL) {
-	  for(i=0; i<osst_max_dev; i++) {
-		tpnt = os_scsi_tapes[i];
-		if(tpnt != NULL && tpnt->device == SDp) {
-			tpnt->device = NULL;
-			for (mode = 0; mode < ST_NBR_MODES; ++mode) {
-				devfs_unregister (tpnt->de_r[mode]);
-				tpnt->de_r[mode] = NULL;
-				devfs_unregister (tpnt->de_n[mode]);
-				tpnt->de_n[mode] = NULL;
-			}
-			devfs_unregister_tape(tpnt->drive->number);
-			put_disk(tpnt->drive);
-			os_scsi_tapes[i] = NULL;
-			scsi_slave_detach(SDp);
-			osst_nr_dev--;
-			write_unlock(&os_scsi_tapes_lock);
-			for (mode = 0; mode < ST_NBR_MODES; ++mode) {
-				device_remove_file(&tpnt->driverfs_dev_r[mode],
-						&dev_attr_type);
-				device_remove_file(&tpnt->driverfs_dev_r[mode],
-						&dev_attr_kdev);
-				device_unregister(&tpnt->driverfs_dev_r[mode]);
-				device_remove_file(&tpnt->driverfs_dev_n[mode],
-						&dev_attr_type);
-				device_remove_file(&tpnt->driverfs_dev_n[mode],
-						&dev_attr_kdev);
-				device_unregister(&tpnt->driverfs_dev_n[mode]);
-			}
-			if (tpnt->header_cache != NULL)
-				vfree(tpnt->header_cache);
-			if (tpnt->buffer) {
-				normalize_buffer(tpnt->buffer);
-				kfree(tpnt->buffer);
+  for(i=0; i < osst_max_dev; i++) {
+	if((tpnt = os_scsi_tapes[i]) && (tpnt->device == SDp)) {
+		tpnt->device = NULL;
+		for (mode = 0; mode < ST_NBR_MODES; ++mode) {
+			devfs_unregister (tpnt->de_r[mode]);
+			tpnt->de_r[mode] = NULL;
+			devfs_unregister (tpnt->de_n[mode]);
+			tpnt->de_n[mode] = NULL;
+		}
+		devfs_unregister_tape(tpnt->drive->number);
+		put_disk(tpnt->drive);
+		os_scsi_tapes[i] = NULL;
+		scsi_slave_detach(SDp);
+		osst_nr_dev--;
+		write_unlock(&os_scsi_tapes_lock);
+		for (mode = 0; mode < ST_NBR_MODES; ++mode) {
+			device_remove_file(&tpnt->driverfs_dev_r[mode],
+					&dev_attr_type);
+			device_remove_file(&tpnt->driverfs_dev_r[mode],
+					&dev_attr_kdev);
+			device_unregister(&tpnt->driverfs_dev_r[mode]);
+			device_remove_file(&tpnt->driverfs_dev_n[mode],
+					&dev_attr_type);
+			device_remove_file(&tpnt->driverfs_dev_n[mode],
+					&dev_attr_kdev);
+			device_unregister(&tpnt->driverfs_dev_n[mode]);
 			}
-			kfree(tpnt);
-			break;
+		if (tpnt->header_cache != NULL) vfree(tpnt->header_cache);
+		if (tpnt->buffer) {
+			normalize_buffer(tpnt->buffer);
+			kfree(tpnt->buffer);
 		}
-	  }
+		kfree(tpnt);
+		return;
+	}
   }
-
   write_unlock(&os_scsi_tapes_lock);
   return;
 }
@@ -5681,12 +5662,8 @@ static int __init init_osst(void)
 	printk(KERN_INFO "osst :I: Tape driver with OnStream support version %s\nosst :I: %s\n", osst_version, cvsid);
 
 	validate_options();
-#if DEBUG
-	 printk(OSST_DEB_MSG "osst :D: %d s/g segments, write threshold %d bytes.\n",
-			 max_sg_segs, osst_write_threshold);
-#endif
-	if ((register_chrdev(OSST_MAJOR, "osst", &osst_fops) < 0) ||
-			scsi_register_device(&osst_template)) {
+	
+	if ((register_chrdev(OSST_MAJOR,"osst", &osst_fops) < 0) || scsi_register_device(&osst_template)) {
 		printk(KERN_ERR "osst :E: Unable to register major %d for OnStream tapes\n", OSST_MAJOR);
 		return 1;
 	}