[PATCH] scsi stuff

The patch below cleans up some SCSI stuff.

The main purpose is to avoid trying to read the partition table
of a removable disk when the drive has told us that no media
are present. (Right now we try to read a 4K block and fail and
retry and fail, and give an I/O error on the first sector,
then try to read the second sector and fail and retry ...)

Unused fields  sector_bit_size  and  sector_bit_shift  in
struct scsi_disk were removed. The field  has_part_table
(that has nothing to do with partition tables) was
renamed to  has_been_registered . The field  ready  was
renamed to  media_present .
The overly long  sd_init_onedisk()  was split up.

When we notice that no media are present anymore, the
partitions are removed from /proc/partitions, but the
drive remains, with size 0.

A future patch will remove the field  capacity  - there are
all too many places where capacities are stored - but the
present patch is large enough already.

There is also a quite independent patch in scsi_error.c
(yesterday someone had an infinite loop retrying to read
bad media) - this patch honours the SCpnt->retries.
In case you applied this already, just ignore the scsi_error.c part.

Also some "Overrides for Emacs" were removed.

drivers/block/genhd.c

@@ -177,9 +177,10 @@ static int show_partition(struct seq_file *part, void *v)
 	if (sgp == gendisk_head)
 		seq_puts(part, "major minor  #blocks  name\n\n");
 
-	/* show all non-0 size partitions of this disk */
+	/* show the full disk and all non-0 size partitions of it */
 	for (n = 0; n < (sgp->nr_real << sgp->minor_shift); n++) {
-		if (sgp->part[n].nr_sects == 0)
+		int minormask = (1<<sgp->minor_shift) - 1;
+		if ((n & minormask) && sgp->part[n].nr_sects == 0)
 			continue;
 		seq_printf(part, "%4d  %4d %10d %s\n",
 			sgp->major, n, sgp->sizes[n],

drivers/scsi/NCR53C9x.c

@@ -2048,7 +2048,7 @@ static int esp_do_data_finale(struct NCR_ESP *esp,
 	 * and not only for the entire host adapter as it is now, the workaround
 	 * is way to expensive performance wise.
 	 * Instead, it turns out that when this happens the target has disconnected
-	 * allready but it doesn't show in the interrupt register. Compensate for
+	 * already but it doesn't show in the interrupt register. Compensate for
 	 * that here to try and avoid a SCSI bus reset.
 	 */
 	if(!esp->fas_premature_intr_workaround && (fifocnt == 1) &&

drivers/scsi/scsi_error.c

@@ -1095,6 +1095,8 @@ int scsi_decide_disposition(Scsi_Cmnd * SCpnt)
  */
 STATIC int scsi_eh_completed_normally(Scsi_Cmnd * SCpnt)
 {
+	int rtn;
+
 	/*
 	 * First check the host byte, to see if there is anything in there
 	 * that would indicate what we need to do.
@@ -1102,20 +1104,25 @@ STATIC int scsi_eh_completed_normally(Scsi_Cmnd * SCpnt)
 	if (host_byte(SCpnt->result) == DID_RESET) {
 		if (SCpnt->flags & IS_RESETTING) {
 			/*
-			 * OK, this is normal.  We don't know whether in fact the
-			 * command in question really needs to be rerun or not - 
-			 * if this was the original data command then the answer is yes,
-			 * otherwise we just flag it as success.
+			 * OK, this is normal.  We don't know whether in fact
+			 * the command in question really needs to be rerun
+			 * or not - if this was the original data command then
+			 * the answer is yes, otherwise we just flag it as
+			 * success.
 			 */
 			SCpnt->flags &= ~IS_RESETTING;
-			return NEEDS_RETRY;
+			goto maybe_retry;
 		}
 		/*
-		 * Rats.  We are already in the error handler, so we now get to try
-		 * and figure out what to do next.  If the sense is valid, we have
-		 * a pretty good idea of what to do.  If not, we mark it as failed.
+		 * Rats.  We are already in the error handler, so we now
+		 * get to try and figure out what to do next.  If the sense
+		 * is valid, we have a pretty good idea of what to do.
+		 * If not, we mark it as failed.
 		 */
-		return scsi_check_sense(SCpnt);
+		rtn = scsi_check_sense(SCpnt);
+		if (rtn == NEEDS_RETRY)
+			goto maybe_retry;
+		return rtn;
 	}
 	if (host_byte(SCpnt->result) != DID_OK) {
 		return FAILED;
@@ -1127,14 +1134,18 @@ STATIC int scsi_eh_completed_normally(Scsi_Cmnd * SCpnt)
 		return FAILED;
 	}
 	/*
-	 * Now, check the status byte to see if this indicates anything special.
+	 * Now, check the status byte to see if this indicates
+	 * anything special.
 	 */
 	switch (status_byte(SCpnt->result)) {
 	case GOOD:
 	case COMMAND_TERMINATED:
 		return SUCCESS;
 	case CHECK_CONDITION:
-		return scsi_check_sense(SCpnt);
+		rtn = scsi_check_sense(SCpnt);
+		if (rtn == NEEDS_RETRY)
+			goto maybe_retry;
+		return rtn;
 	case CONDITION_GOOD:
 	case INTERMEDIATE_GOOD:
 	case INTERMEDIATE_C_GOOD:
@@ -1149,6 +1160,14 @@ STATIC int scsi_eh_completed_normally(Scsi_Cmnd * SCpnt)
 		return FAILED;
 	}
 	return FAILED;
+
+ maybe_retry:
+	if ((++SCpnt->retries) < SCpnt->allowed) {
+		return NEEDS_RETRY;
+	} else {
+		/* No more retries - report this one back to upper level */
+		return SUCCESS;
+	}
 }
 
 /*

drivers/scsi/scsi_ioctl.c

@@ -127,7 +127,7 @@ static int ioctl_internal_command(Scsi_Device * dev, char *cmd,
 				/* gag this error, VFS will log it anyway /axboe */
 				/* printk(KERN_INFO "Disc change detected.\n"); */
 				break;
-			};
+			}
 		default:	/* Fall through for non-removable media */
 			printk("SCSI error: host %d id %d lun %d return code = %x\n",
 			       dev->host->host_no,
@@ -139,7 +139,7 @@ static int ioctl_internal_command(Scsi_Device * dev, char *cmd,
 			       sense_error(SRpnt->sr_sense_buffer[0]),
 			       SRpnt->sr_sense_buffer[2] & 0xf);
 
-		};
+		}
 
 	result = SRpnt->sr_result;
 
@@ -152,7 +152,7 @@ static int ioctl_internal_command(Scsi_Device * dev, char *cmd,
 }
 
 /*
- * This interface is depreciated - users should use the scsi generic (sg)
+ * This interface is deprecated - users should use the scsi generic (sg)
  * interface instead, as this is a more flexible approach to performing
  * generic SCSI commands on a device.
  *
@@ -516,22 +516,3 @@ int kernel_scsi_ioctl(Scsi_Device * dev, int cmd, void *arg)
 	set_fs(oldfs);
 	return tmp;
 }
-
-/*
- * Overrides for Emacs so that we almost follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: nil
- * tab-width: 8
- * End:
- */

drivers/scsi/sd.h

@@ -11,9 +11,6 @@
  */
 #ifndef _SD_H
 #define _SD_H
-/*
-   $Header: /usr/src/linux/kernel/blk_drv/scsi/RCS/sd.h,v 1.1 1992/07/24 06:27:38 root Exp root $
- */
 
 #ifndef _SCSI_H
 #include "scsi.h"
@@ -26,13 +23,11 @@
 extern struct hd_struct *sd;
 
 typedef struct scsi_disk {
-	unsigned capacity;	/* size in blocks */
+	unsigned capacity;		/* size in 512-byte sectors */
 	Scsi_Device *device;
-	unsigned char ready;	/* flag ready for FLOPTICAL */
-	unsigned char write_prot;	/* flag write_protect for rmvable dev */
-	unsigned char sector_bit_size;	/* sector_size = 2 to the  bit size power */
-	unsigned char sector_bit_shift;		/* power of 2 sectors per FS block */
-	unsigned has_part_table:1;	/* has partition table */
+	unsigned char media_present;
+	unsigned char write_prot;
+	unsigned has_been_registered:1;
 } Scsi_Disk;
 
 extern int revalidate_scsidisk(kdev_t dev, int maxusage);
@@ -48,22 +43,3 @@ extern kdev_t sd_find_target(void *host, int tgt);
 #define SD_PARTITION(i)		(((major(i) & SD_MAJOR_MASK) << 8) | (minor(i) & 255))
 
 #endif
-
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: nil
- * tab-width: 8
- * End:
- */

drivers/scsi/sr.h

@@ -24,8 +24,6 @@ typedef struct {
 	Scsi_Device *device;
 	unsigned int vendor;	/* vendor code, see sr_vendor.c         */
 	unsigned long ms_offset;	/* for reading multisession-CD's        */
-	unsigned char sector_bit_size;	/* sector size = 2^sector_bit_size      */
-	unsigned char sector_bit_shift;		/* sectors/FS block = 2^sector_bit_shift */
 	unsigned needs_sector_size:1;	/* needs to get sector size */
 	unsigned use:1;		/* is this device still supportable     */
 	unsigned xa_flag:1;	/* CD has XA sectors ? */

fs/partitions/check.c

@@ -412,8 +412,8 @@ void grok_partitions(kdev_t dev, long size)
 
 	g->part[first_minor].nr_sects = size;
 
-	/* No such device or no minors to use for partitions */
-	if (!size || minors == 1)
+	/* No minors to use for partitions */
+	if (minors == 1)
 		return;
 
 	if (g->sizes) {
@@ -422,6 +422,11 @@ void grok_partitions(kdev_t dev, long size)
 			g->sizes[i] = 0;
 	}
 	blk_size[g->major] = g->sizes;
+
+	/* No such device (e.g., media were just removed) */
+	if (!size)
+		return;
+
 	check_partition(g, mk_kdev(g->major, first_minor), 1 + first_minor);
 
  	/*

include/scsi/scsi.h

@@ -223,23 +223,4 @@ typedef struct scsi_lun {
 /* Used to get the PCI location of a device */
 #define SCSI_IOCTL_GET_PCI 0x5387
 
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-indent-level: 4 
- * c-brace-imaginary-offset: 0
- * c-brace-offset: -4
- * c-argdecl-indent: 4
- * c-label-offset: -4
- * c-continued-statement-offset: 4
- * c-continued-brace-offset: 0
- * indent-tabs-mode: nil
- * tab-width: 8
- * End:
- */
-
 #endif