1 files changed, 272 insertions, 183 deletions

diff --git a/block/partitions/ibm.c b/block/partitions/ibm.c
index 1104acac780b..47a61474e795 100644
--- a/block/partitions/ibm.c
+++ b/block/partitions/ibm.c
@@ -1,9 +1,8 @@
 /*
- * File...........: linux/fs/partitions/ibm.c
  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
  *                  Volker Sameske <sameske@de.ibm.com>
  * Bugreports.to..: <Linux390@de.ibm.com>
- * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
+ * Copyright IBM Corp. 1999, 2012
  */
 
 #include <linux/buffer_head.h>
@@ -17,17 +16,23 @@
 #include "check.h"
 #include "ibm.h"
 
+
+union label_t {
+	struct vtoc_volume_label_cdl vol;
+	struct vtoc_volume_label_ldl lnx;
+	struct vtoc_cms_label cms;
+};
+
 /*
  * compute the block number from a
  * cyl-cyl-head-head structure
  */
-static sector_t
-cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
-
+static sector_t cchh2blk(struct vtoc_cchh *ptr, struct hd_geometry *geo)
+{
 	sector_t cyl;
 	__u16 head;
 
-	/*decode cylinder and heads for large volumes */
+	/* decode cylinder and heads for large volumes */
 	cyl = ptr->hh & 0xFFF0;
 	cyl <<= 12;
 	cyl |= ptr->cc;
@@ -40,13 +45,12 @@ cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
  * compute the block number from a
  * cyl-cyl-head-head-block structure
  */
-static sector_t
-cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
-
+static sector_t cchhb2blk(struct vtoc_cchhb *ptr, struct hd_geometry *geo)
+{
 	sector_t cyl;
 	__u16 head;
 
-	/*decode cylinder and heads for large volumes */
+	/* decode cylinder and heads for large volumes */
 	cyl = ptr->hh & 0xFFF0;
 	cyl <<= 12;
 	cyl |= ptr->cc;
@@ -56,26 +60,243 @@ cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
 		ptr->b;
 }
 
+static int find_label(struct parsed_partitions *state,
+		      dasd_information2_t *info,
+		      struct hd_geometry *geo,
+		      int blocksize,
+		      sector_t *labelsect,
+		      char name[],
+		      char type[],
+		      union label_t *label)
+{
+	Sector sect;
+	unsigned char *data;
+	sector_t testsect[3];
+	unsigned char temp[5];
+	int found = 0;
+	int i, testcount;
+
+	/* There a three places where we may find a valid label:
+	 * - on an ECKD disk it's block 2
+	 * - on an FBA disk it's block 1
+	 * - on an CMS formatted FBA disk it is sector 1, even if the block size
+	 *   is larger than 512 bytes (possible if the DIAG discipline is used)
+	 * If we have a valid info structure, then we know exactly which case we
+	 * have, otherwise we just search through all possebilities.
+	 */
+	if (info) {
+		if ((info->cu_type == 0x6310 && info->dev_type == 0x9336) ||
+		    (info->cu_type == 0x3880 && info->dev_type == 0x3370))
+			testsect[0] = info->label_block;
+		else
+			testsect[0] = info->label_block * (blocksize >> 9);
+		testcount = 1;
+	} else {
+		testsect[0] = 1;
+		testsect[1] = (blocksize >> 9);
+		testsect[2] = 2 * (blocksize >> 9);
+		testcount = 3;
+	}
+	for (i = 0; i < testcount; ++i) {
+		data = read_part_sector(state, testsect[i], &sect);
+		if (data == NULL)
+			continue;
+		memcpy(label, data, sizeof(*label));
+		memcpy(temp, data, 4);
+		temp[4] = 0;
+		EBCASC(temp, 4);
+		put_dev_sector(sect);
+		if (!strcmp(temp, "VOL1") ||
+		    !strcmp(temp, "LNX1") ||
+		    !strcmp(temp, "CMS1")) {
+			if (!strcmp(temp, "VOL1")) {
+				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);
+			*labelsect = testsect[i];
+			found = 1;
+			break;
+		}
+	}
+	if (!found)
+		memset(label, 0, sizeof(*label));
+
+	return found;
+}
+
+static int find_vol1_partitions(struct parsed_partitions *state,
+				struct hd_geometry *geo,
+				int blocksize,
+				char name[],
+				union label_t *label)
+{
+	sector_t blk;
+	int counter;
+	char tmp[64];
+	Sector sect;
+	unsigned char *data;
+	loff_t offset, size;
+	struct vtoc_format1_label f1;
+	int secperblk;
+
+	snprintf(tmp, sizeof(tmp), "VOL1/%8s:", name);
+	strlcat(state->pp_buf, tmp, PAGE_SIZE);
+	/*
+	 * get start of VTOC from the disk label and then search for format1
+	 * and format8 labels
+	 */
+	secperblk = blocksize >> 9;
+	blk = cchhb2blk(&label->vol.vtoc, geo) + 1;
+	counter = 0;
+	data = read_part_sector(state, blk * secperblk, &sect);
+	while (data != NULL) {
+		memcpy(&f1, data, sizeof(struct vtoc_format1_label));
+		put_dev_sector(sect);
+		/* skip FMT4 / FMT5 / FMT7 labels */
+		if (f1.DS1FMTID == _ascebc['4']
+		    || f1.DS1FMTID == _ascebc['5']
+		    || f1.DS1FMTID == _ascebc['7']
+		    || f1.DS1FMTID == _ascebc['9']) {
+			blk++;
+			data = read_part_sector(state, blk * secperblk, &sect);
+			continue;
+		}
+		/* 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 */
+		offset = cchh2blk(&f1.DS1EXT1.llimit, geo);
+		size  = cchh2blk(&f1.DS1EXT1.ulimit, geo) -
+			offset + geo->sectors;
+		offset *= secperblk;
+		size *= secperblk;
+		if (counter >= state->limit)
+			break;
+		put_partition(state, counter + 1, offset, size);
+		counter++;
+		blk++;
+		data = read_part_sector(state, blk * secperblk, &sect);
+	}
+	strlcat(state->pp_buf, "\n", PAGE_SIZE);
+
+	if (!data)
+		return -1;
+
+	return 1;
+}
+
+static int find_lnx1_partitions(struct parsed_partitions *state,
+				struct hd_geometry *geo,
+				int blocksize,
+				char name[],
+				union label_t *label,
+				sector_t labelsect,
+				loff_t i_size,
+				dasd_information2_t *info)
+{
+	loff_t offset, geo_size, size;
+	char tmp[64];
+	int secperblk;
+
+	snprintf(tmp, sizeof(tmp), "LNX1/%8s:", name);
+	strlcat(state->pp_buf, tmp, PAGE_SIZE);
+	secperblk = blocksize >> 9;
+	if (label->lnx.ldl_version == 0xf2) {
+		size = label->lnx.formatted_blocks * secperblk;
+	} else {
+		/*
+		 * Formated w/o large volume support. If the sanity check
+		 * 'size based on geo == size based on i_size' is true, then
+		 * we can safely assume that we know the formatted size of
+		 * the disk, otherwise we need additional information
+		 * that we can only get from a real DASD device.
+		 */
+		geo_size = geo->cylinders * geo->heads
+			* geo->sectors * secperblk;
+		size = i_size >> 9;
+		if (size != geo_size) {
+			if (!info) {
+				strlcat(state->pp_buf, "\n", PAGE_SIZE);
+				return 1;
+			}
+			if (!strcmp(info->type, "ECKD"))
+				if (geo_size < size)
+					size = geo_size;
+			/* else keep size based on i_size */
+		}
+	}
+	/* first and only partition starts in the first block after the label */
+	offset = labelsect + secperblk;
+	put_partition(state, 1, offset, size - offset);
+	strlcat(state->pp_buf, "\n", PAGE_SIZE);
+	return 1;
+}
+
+static int find_cms1_partitions(struct parsed_partitions *state,
+				struct hd_geometry *geo,
+				int blocksize,
+				char name[],
+				union label_t *label,
+				sector_t labelsect)
+{
+	loff_t offset, size;
+	char tmp[64];
+	int secperblk;
+
+	/*
+	 * VM style CMS1 labeled disk
+	 */
+	blocksize = label->cms.block_size;
+	secperblk = blocksize >> 9;
+	if (label->cms.disk_offset != 0) {
+		snprintf(tmp, sizeof(tmp), "CMS1/%8s(MDSK):", name);
+		strlcat(state->pp_buf, tmp, PAGE_SIZE);
+		/* disk is reserved minidisk */
+		offset = label->cms.disk_offset * secperblk;
+		size = (label->cms.block_count - 1) * secperblk;
+	} else {
+		snprintf(tmp, sizeof(tmp), "CMS1/%8s:", name);
+		strlcat(state->pp_buf, tmp, PAGE_SIZE);
+		/*
+		 * Special case for FBA devices:
+		 * If an FBA device is CMS formatted with blocksize > 512 byte
+		 * and the DIAG discipline is used, then the CMS label is found
+		 * in sector 1 instead of block 1. However, the partition is
+		 * still supposed to start in block 2.
+		 */
+		if (labelsect == 1)
+			offset = 2 * secperblk;
+		else
+			offset = labelsect + secperblk;
+		size = label->cms.block_count * secperblk;
+	}
+
+	put_partition(state, 1, offset, size-offset);
+	strlcat(state->pp_buf, "\n", PAGE_SIZE);
+	return 1;
+}
+
+
 /*
+ * This is the main function, called by check.c
  */
 int ibm_partition(struct parsed_partitions *state)
 {
 	struct block_device *bdev = state->bdev;
 	int blocksize, res;
-	loff_t i_size, offset, size, fmt_size;
+	loff_t i_size, offset, size;
 	dasd_information2_t *info;
 	struct hd_geometry *geo;
 	char type[5] = {0,};
 	char name[7] = {0,};
-	union label_t {
-		struct vtoc_volume_label_cdl vol;
-		struct vtoc_volume_label_ldl lnx;
-		struct vtoc_cms_label cms;
-	} *label;
-	unsigned char *data;
-	Sector sect;
 	sector_t labelsect;
-	char tmp[64];
+	union label_t *label;
 
 	res = 0;
 	blocksize = bdev_logical_block_size(bdev);
@@ -84,7 +305,6 @@ int ibm_partition(struct parsed_partitions *state)
 	i_size = i_size_read(bdev->bd_inode);
 	if (i_size == 0)
 		goto out_exit;
-
 	info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL);
 	if (info == NULL)
 		goto out_exit;
@@ -94,176 +314,45 @@ int ibm_partition(struct parsed_partitions *state)
 	label = kmalloc(sizeof(union label_t), GFP_KERNEL);
 	if (label == NULL)
 		goto out_nolab;
-
-	if (ioctl_by_bdev(bdev, BIODASDINFO2, (unsigned long)info) != 0 ||
-	    ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0)
+	if (ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0)
 		goto out_freeall;
-
-	/*
-	 * Special case for FBA disks: label sector does not depend on
-	 * blocksize.
-	 */
-	if ((info->cu_type == 0x6310 && info->dev_type == 0x9336) ||
-	    (info->cu_type == 0x3880 && info->dev_type == 0x3370))
-		labelsect = info->label_block;
-	else
-		labelsect = info->label_block * (blocksize >> 9);
-
-	/*
-	 * Get volume label, extract name and type.
-	 */
-	data = read_part_sector(state, labelsect, &sect);
-	if (data == NULL)
-		goto out_readerr;
-
-	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);
+	if (ioctl_by_bdev(bdev, BIODASDINFO2, (unsigned long)info) != 0) {
+		kfree(info);
+		info = NULL;
 	}
-	EBCASC(type, 4);
-	EBCASC(name, 6);
-
-	res = 1;
 
-	/*
-	 * Three different formats: LDL, CDL and unformated disk
-	 *
-	 * identified by info->format
-	 *
-	 * unformated disks we do not have to care about
-	 */
-	if (info->format == DASD_FORMAT_LDL) {
-		if (strncmp(type, "CMS1", 4) == 0) {
-			/*
-			 * VM style CMS1 labeled disk
-			 */
-			blocksize = label->cms.block_size;
-			if (label->cms.disk_offset != 0) {
-				snprintf(tmp, sizeof(tmp), "CMS1/%8s(MDSK):", name);
-				strlcat(state->pp_buf, tmp, PAGE_SIZE);
-				/* disk is reserved minidisk */
-				offset = label->cms.disk_offset;
-				size = (label->cms.block_count - 1)
-					* (blocksize >> 9);
-			} else {
-				snprintf(tmp, sizeof(tmp), "CMS1/%8s:", name);
-				strlcat(state->pp_buf, tmp, PAGE_SIZE);
-				offset = (info->label_block + 1);
-				size = label->cms.block_count
-					* (blocksize >> 9);
-			}
-			put_partition(state, 1, offset*(blocksize >> 9),
-				      size-offset*(blocksize >> 9));
-		} else {
-			if (strncmp(type, "LNX1", 4) == 0) {
-				snprintf(tmp, sizeof(tmp), "LNX1/%8s:", name);
-				strlcat(state->pp_buf, tmp, PAGE_SIZE);
-				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 */
-				strlcat(state->pp_buf, "(nonl)", PAGE_SIZE);
-				size = i_size >> 9;
-				offset = (info->label_block + 1);
-			}
-			put_partition(state, 1, offset*(blocksize >> 9),
-				      size-offset*(blocksize >> 9));
+	if (find_label(state, info, geo, blocksize, &labelsect, name, type,
+		       label)) {
+		if (!strncmp(type, "VOL1", 4)) {
+			res = find_vol1_partitions(state, geo, blocksize, name,
+						   label);
+		} else if (!strncmp(type, "LNX1", 4)) {
+			res = find_lnx1_partitions(state, geo, blocksize, name,
+						   label, labelsect, i_size,
+						   info);
+		} else if (!strncmp(type, "CMS1", 4)) {
+			res = find_cms1_partitions(state, geo, blocksize, name,
+						   label, labelsect);
 		}
-	} else if (info->format == DASD_FORMAT_CDL) {
-		/*
-		 * New style CDL formatted disk
-		 */
-		sector_t blk;
-		int counter;
-
+	} else if (info) {
 		/*
-		 * check if VOL1 label is available
-		 * if not, something is wrong, skipping partition detection
+		 * ugly but needed for backward compatibility:
+		 * If the block device is a DASD (i.e. BIODASDINFO2 works),
+		 * then we claim it in any case, even though it has no valid
+		 * label. If it has the LDL format, then we simply define a
+		 * partition as if it had an LNX1 label.
 		 */
-		if (strncmp(type, "VOL1",  4) == 0) {
-			snprintf(tmp, sizeof(tmp), "VOL1/%8s:", name);
-			strlcat(state->pp_buf, tmp, PAGE_SIZE);
-			/*
-			 * get block number and read then go through format1
-			 * labels
-			 */
-			blk = cchhb2blk(&label->vol.vtoc, geo) + 1;
-			counter = 0;
-			data = read_part_sector(state, blk * (blocksize/512),
-						&sect);
-			while (data != NULL) {
-				struct vtoc_format1_label f1;
-
-				memcpy(&f1, data,
-				       sizeof(struct vtoc_format1_label));
-				put_dev_sector(sect);
-
-				/* skip FMT4 / FMT5 / FMT7 labels */
-				if (f1.DS1FMTID == _ascebc['4']
-				    || f1.DS1FMTID == _ascebc['5']
-				    || f1.DS1FMTID == _ascebc['7']
-				    || f1.DS1FMTID == _ascebc['9']) {
-					blk++;
-					data = read_part_sector(state,
-						blk * (blocksize/512), &sect);
-					continue;
-				}
-
-				/* 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 */
-				offset = cchh2blk(&f1.DS1EXT1.llimit, geo);
-				size  = cchh2blk(&f1.DS1EXT1.ulimit, geo) -
-					offset + geo->sectors;
-				if (counter >= state->limit)
-					break;
-				put_partition(state, counter + 1,
-					      offset * (blocksize >> 9),
-					      size * (blocksize >> 9));
-				counter++;
-				blk++;
-				data = read_part_sector(state,
-						blk * (blocksize/512), &sect);
-			}
-
-			if (!data)
-				/* Are we not supposed to report this ? */
-				goto out_readerr;
-		} else
-			printk(KERN_INFO "Expected Label VOL1 not "
-			       "found, treating as CDL formated Disk");
-
-	}
-
-	strlcat(state->pp_buf, "\n", PAGE_SIZE);
-	goto out_freeall;
-
+		res = 1;
+		if (info->format == DASD_FORMAT_LDL) {
+			strlcat(state->pp_buf, "(nonl)", PAGE_SIZE);
+			size = i_size >> 9;
+			offset = (info->label_block + 1) * (blocksize >> 9);
+			put_partition(state, 1, offset, size-offset);
+			strlcat(state->pp_buf, "\n", PAGE_SIZE);
+		}
+	} else
+		res = 0;
 
-out_readerr:
-	res = -1;
 out_freeall:
 	kfree(label);
 out_nolab: