[S390] dasd: add large volume support

The dasd device driver will now support ECKD devices with more then
65520 cylinders.
In the traditional ECKD adressing scheme each track is addressed
by a 16-bit cylinder and 16-bit head number. The new addressing
scheme makes use of the fact that the actual number of heads is
never larger then 15, so 12 bits of the head number can be redefined
to be part of the cylinder address.

Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/fs/partitions/ibm.c b/fs/partitions/ibm.c
index 1e064c4..4629768 100644
--- a/fs/partitions/ibm.c
+++ b/fs/partitions/ibm.c
@@ -21,20 +21,38 @@
  * compute the block number from a
  * cyl-cyl-head-head structure
  */
-static inline int
+static sector_t
 cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
-        return ptr->cc * geo->heads * geo->sectors +
-	       ptr->hh * geo->sectors;
+
+	sector_t cyl;
+	__u16 head;
+
+	/*decode cylinder and heads for large volumes */
+	cyl = ptr->hh & 0xFFF0;
+	cyl <<= 12;
+	cyl |= ptr->cc;
+	head = ptr->hh & 0x000F;
+	return cyl * geo->heads * geo->sectors +
+	       head * geo->sectors;
 }
 
 /*
  * compute the block number from a
  * cyl-cyl-head-head-block structure
  */
-static inline int
+static sector_t
 cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
-        return ptr->cc * geo->heads * geo->sectors +
-		ptr->hh * geo->sectors +
+
+	sector_t cyl;
+	__u16 head;
+
+	/*decode cylinder and heads for large volumes */
+	cyl = ptr->hh & 0xFFF0;
+	cyl <<= 12;
+	cyl |= ptr->cc;
+	head = ptr->hh & 0x000F;
+	return	cyl * geo->heads * geo->sectors +
+		head * geo->sectors +
 		ptr->b;
 }
 
@@ -43,14 +61,15 @@
 int
 ibm_partition(struct parsed_partitions *state, struct block_device *bdev)
 {
-	int blocksize, offset, size,res;
-	loff_t i_size;
+	int blocksize, res;
+	loff_t i_size, offset, size, fmt_size;
 	dasd_information2_t *info;
 	struct hd_geometry *geo;
 	char type[5] = {0,};
 	char name[7] = {0,};
 	union label_t {
-		struct vtoc_volume_label vol;
+		struct vtoc_volume_label_cdl vol;
+		struct vtoc_volume_label_ldl lnx;
 		struct vtoc_cms_label cms;
 	} *label;
 	unsigned char *data;
@@ -85,14 +104,16 @@
 	if (data == NULL)
 		goto out_readerr;
 
-	strncpy (type, data, 4);
-	if ((!info->FBA_layout) && (!strcmp(info->type, "ECKD")))
-		strncpy(name, data + 8, 6);
-	else
-		strncpy(name, data + 4, 6);
 	memcpy(label, data, sizeof(union label_t));
 	put_dev_sector(sect);
 
+	if ((!info->FBA_layout) && (!strcmp(info->type, "ECKD"))) {
+		strncpy(type, label->vol.vollbl, 4);
+		strncpy(name, label->vol.volid, 6);
+	} else {
+		strncpy(type, label->lnx.vollbl, 4);
+		strncpy(name, label->lnx.volid, 6);
+	}
 	EBCASC(type, 4);
 	EBCASC(name, 6);
 
@@ -110,36 +131,54 @@
 			/*
 			 * VM style CMS1 labeled disk
 			 */
+			blocksize = label->cms.block_size;
 			if (label->cms.disk_offset != 0) {
 				printk("CMS1/%8s(MDSK):", name);
 				/* disk is reserved minidisk */
-				blocksize = label->cms.block_size;
 				offset = label->cms.disk_offset;
 				size = (label->cms.block_count - 1)
 					* (blocksize >> 9);
 			} else {
 				printk("CMS1/%8s:", name);
 				offset = (info->label_block + 1);
-				size = i_size >> 9;
+				size = label->cms.block_count
+					* (blocksize >> 9);
 			}
-		} else {
-			/*
-			 * Old style LNX1 or unlabeled disk
-			 */
-			if (strncmp(type, "LNX1", 4) == 0)
-				printk ("LNX1/%8s:", name);
-			else
-				printk("(nonl)");
-			offset = (info->label_block + 1);
-			size = i_size >> 9;
-		}
-		put_partition(state, 1, offset*(blocksize >> 9),
+			put_partition(state, 1, offset*(blocksize >> 9),
 				      size-offset*(blocksize >> 9));
+		} else {
+			if (strncmp(type, "LNX1", 4) == 0) {
+				printk("LNX1/%8s:", name);
+				if (label->lnx.ldl_version == 0xf2) {
+					fmt_size = label->lnx.formatted_blocks
+						* (blocksize >> 9);
+				} else if (!strcmp(info->type, "ECKD")) {
+					/* formated w/o large volume support */
+					fmt_size = geo->cylinders * geo->heads
+					      * geo->sectors * (blocksize >> 9);
+				} else {
+					/* old label and no usable disk geometry
+					 * (e.g. DIAG) */
+					fmt_size = i_size >> 9;
+				}
+				size = i_size >> 9;
+				if (fmt_size < size)
+					size = fmt_size;
+				offset = (info->label_block + 1);
+			} else {
+				/* unlabeled disk */
+				printk("(nonl)");
+				size = i_size >> 9;
+				offset = (info->label_block + 1);
+			}
+			put_partition(state, 1, offset*(blocksize >> 9),
+				      size-offset*(blocksize >> 9));
+		}
 	} else if (info->format == DASD_FORMAT_CDL) {
 		/*
 		 * New style CDL formatted disk
 		 */
-		unsigned int blk;
+		sector_t blk;
 		int counter;
 
 		/*
@@ -166,7 +205,8 @@
 				/* skip FMT4 / FMT5 / FMT7 labels */
 				if (f1.DS1FMTID == _ascebc['4']
 				    || f1.DS1FMTID == _ascebc['5']
-				    || f1.DS1FMTID == _ascebc['7']) {
+				    || f1.DS1FMTID == _ascebc['7']
+				    || f1.DS1FMTID == _ascebc['9']) {
 					blk++;
 					data = read_dev_sector(bdev, blk *
 							       (blocksize/512),
@@ -174,8 +214,9 @@
 					continue;
 				}
 
-				/* only FMT1 valid at this point */
-				if (f1.DS1FMTID != _ascebc['1'])
+				/* only FMT1 and 8 labels valid at this point */
+				if (f1.DS1FMTID != _ascebc['1'] &&
+				    f1.DS1FMTID != _ascebc['8'])
 					break;
 
 				/* OK, we got valid partition data */