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1// SPDX-License-Identifier: GPL-2.02/*3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>4 *                  Volker Sameske <sameske@de.ibm.com>5 * Bugreports.to..: <Linux390@de.ibm.com>6 * Copyright IBM Corp. 1999, 20127 */8 9#include <linux/buffer_head.h>10#include <linux/hdreg.h>11#include <linux/slab.h>12#include <asm/dasd.h>13#include <asm/ebcdic.h>14#include <linux/uaccess.h>15#include <asm/vtoc.h>16#include <linux/module.h>17#include <linux/dasd_mod.h>18 19#include "check.h"20 21union label_t {22	struct vtoc_volume_label_cdl vol;23	struct vtoc_volume_label_ldl lnx;24	struct vtoc_cms_label cms;25};26 27/*28 * compute the block number from a29 * cyl-cyl-head-head structure30 */31static sector_t cchh2blk(struct vtoc_cchh *ptr, struct hd_geometry *geo)32{33	sector_t cyl;34	__u16 head;35 36	/* decode cylinder and heads for large volumes */37	cyl = ptr->hh & 0xFFF0;38	cyl <<= 12;39	cyl |= ptr->cc;40	head = ptr->hh & 0x000F;41	return cyl * geo->heads * geo->sectors +42	       head * geo->sectors;43}44 45/*46 * compute the block number from a47 * cyl-cyl-head-head-block structure48 */49static sector_t cchhb2blk(struct vtoc_cchhb *ptr, struct hd_geometry *geo)50{51	sector_t cyl;52	__u16 head;53 54	/* decode cylinder and heads for large volumes */55	cyl = ptr->hh & 0xFFF0;56	cyl <<= 12;57	cyl |= ptr->cc;58	head = ptr->hh & 0x000F;59	return	cyl * geo->heads * geo->sectors +60		head * geo->sectors +61		ptr->b;62}63 64/* Volume Label Type/ID Length */65#define DASD_VOL_TYPE_LEN	466#define DASD_VOL_ID_LEN		667 68/* Volume Label Types */69#define DASD_VOLLBL_TYPE_VOL1 070#define DASD_VOLLBL_TYPE_LNX1 171#define DASD_VOLLBL_TYPE_CMS1 272 73struct dasd_vollabel {74	char *type;75	int idx;76};77 78static struct dasd_vollabel dasd_vollabels[] = {79	[DASD_VOLLBL_TYPE_VOL1] = {80		.type = "VOL1",81		.idx = DASD_VOLLBL_TYPE_VOL1,82	},83	[DASD_VOLLBL_TYPE_LNX1] = {84		.type = "LNX1",85		.idx = DASD_VOLLBL_TYPE_LNX1,86	},87	[DASD_VOLLBL_TYPE_CMS1] = {88		.type = "CMS1",89		.idx = DASD_VOLLBL_TYPE_CMS1,90	},91};92 93static int get_label_by_type(const char *type)94{95	int i;96 97	for (i = 0; i < ARRAY_SIZE(dasd_vollabels); i++) {98		if (!memcmp(type, dasd_vollabels[i].type, DASD_VOL_TYPE_LEN))99			return dasd_vollabels[i].idx;100	}101 102	return -1;103}104 105static int find_label(struct parsed_partitions *state,106		      dasd_information2_t *info,107		      struct hd_geometry *geo,108		      int blocksize,109		      sector_t *labelsect,110		      char name[],111		      char type[],112		      union label_t *label)113{114	sector_t testsect[3];115	int i, testcount;116	Sector sect;117	void *data;118 119	/* There a three places where we may find a valid label:120	 * - on an ECKD disk it's block 2121	 * - on an FBA disk it's block 1122	 * - on an CMS formatted FBA disk it is sector 1, even if the block size123	 *   is larger than 512 bytes (possible if the DIAG discipline is used)124	 * If we have a valid info structure, then we know exactly which case we125	 * have, otherwise we just search through all possebilities.126	 */127	if (info) {128		if ((info->cu_type == 0x6310 && info->dev_type == 0x9336) ||129		    (info->cu_type == 0x3880 && info->dev_type == 0x3370))130			testsect[0] = info->label_block;131		else132			testsect[0] = info->label_block * (blocksize >> 9);133		testcount = 1;134	} else {135		testsect[0] = 1;136		testsect[1] = (blocksize >> 9);137		testsect[2] = 2 * (blocksize >> 9);138		testcount = 3;139	}140	for (i = 0; i < testcount; ++i) {141		data = read_part_sector(state, testsect[i], &sect);142		if (data == NULL)143			continue;144		memcpy(label, data, sizeof(*label));145		memcpy(type, data, DASD_VOL_TYPE_LEN);146		EBCASC(type, DASD_VOL_TYPE_LEN);147		put_dev_sector(sect);148		switch (get_label_by_type(type)) {149		case DASD_VOLLBL_TYPE_VOL1:150			memcpy(name, label->vol.volid, DASD_VOL_ID_LEN);151			EBCASC(name, DASD_VOL_ID_LEN);152			*labelsect = testsect[i];153			return 1;154		case DASD_VOLLBL_TYPE_LNX1:155		case DASD_VOLLBL_TYPE_CMS1:156			memcpy(name, label->lnx.volid, DASD_VOL_ID_LEN);157			EBCASC(name, DASD_VOL_ID_LEN);158			*labelsect = testsect[i];159			return 1;160		default:161			break;162		}163	}164 165	return 0;166}167 168static int find_vol1_partitions(struct parsed_partitions *state,169				struct hd_geometry *geo,170				int blocksize,171				char name[],172				union label_t *label)173{174	sector_t blk;175	int counter;176	char tmp[64];177	Sector sect;178	unsigned char *data;179	loff_t offset, size;180	struct vtoc_format1_label f1;181	int secperblk;182 183	snprintf(tmp, sizeof(tmp), "VOL1/%8s:", name);184	strlcat(state->pp_buf, tmp, PAGE_SIZE);185	/*186	 * get start of VTOC from the disk label and then search for format1187	 * and format8 labels188	 */189	secperblk = blocksize >> 9;190	blk = cchhb2blk(&label->vol.vtoc, geo) + 1;191	counter = 0;192	data = read_part_sector(state, blk * secperblk, &sect);193	while (data != NULL) {194		memcpy(&f1, data, sizeof(struct vtoc_format1_label));195		put_dev_sector(sect);196		/* skip FMT4 / FMT5 / FMT7 labels */197		if (f1.DS1FMTID == _ascebc['4']198		    || f1.DS1FMTID == _ascebc['5']199		    || f1.DS1FMTID == _ascebc['7']200		    || f1.DS1FMTID == _ascebc['9']) {201			blk++;202			data = read_part_sector(state, blk * secperblk, &sect);203			continue;204		}205		/* only FMT1 and 8 labels valid at this point */206		if (f1.DS1FMTID != _ascebc['1'] &&207		    f1.DS1FMTID != _ascebc['8'])208			break;209		/* OK, we got valid partition data */210		offset = cchh2blk(&f1.DS1EXT1.llimit, geo);211		size  = cchh2blk(&f1.DS1EXT1.ulimit, geo) -212			offset + geo->sectors;213		offset *= secperblk;214		size *= secperblk;215		if (counter >= state->limit)216			break;217		put_partition(state, counter + 1, offset, size);218		counter++;219		blk++;220		data = read_part_sector(state, blk * secperblk, &sect);221	}222	strlcat(state->pp_buf, "\n", PAGE_SIZE);223 224	if (!data)225		return -1;226 227	return 1;228}229 230static int find_lnx1_partitions(struct parsed_partitions *state,231				struct hd_geometry *geo,232				int blocksize,233				char name[],234				union label_t *label,235				sector_t labelsect,236				sector_t nr_sectors,237				dasd_information2_t *info)238{239	loff_t offset, geo_size, size;240	char tmp[64];241	int secperblk;242 243	snprintf(tmp, sizeof(tmp), "LNX1/%8s:", name);244	strlcat(state->pp_buf, tmp, PAGE_SIZE);245	secperblk = blocksize >> 9;246	if (label->lnx.ldl_version == 0xf2) {247		size = label->lnx.formatted_blocks * secperblk;248	} else {249		/*250		 * Formated w/o large volume support. If the sanity check251		 * 'size based on geo == size based on nr_sectors' is true, then252		 * we can safely assume that we know the formatted size of253		 * the disk, otherwise we need additional information254		 * that we can only get from a real DASD device.255		 */256		geo_size = geo->cylinders * geo->heads257			* geo->sectors * secperblk;258		size = nr_sectors;259		if (size != geo_size) {260			if (!info) {261				strlcat(state->pp_buf, "\n", PAGE_SIZE);262				return 1;263			}264			if (!strcmp(info->type, "ECKD"))265				if (geo_size < size)266					size = geo_size;267			/* else keep size based on nr_sectors */268		}269	}270	/* first and only partition starts in the first block after the label */271	offset = labelsect + secperblk;272	put_partition(state, 1, offset, size - offset);273	strlcat(state->pp_buf, "\n", PAGE_SIZE);274	return 1;275}276 277static int find_cms1_partitions(struct parsed_partitions *state,278				struct hd_geometry *geo,279				int blocksize,280				char name[],281				union label_t *label,282				sector_t labelsect)283{284	loff_t offset, size;285	char tmp[64];286	int secperblk;287 288	/*289	 * VM style CMS1 labeled disk290	 */291	blocksize = label->cms.block_size;292	secperblk = blocksize >> 9;293	if (label->cms.disk_offset != 0) {294		snprintf(tmp, sizeof(tmp), "CMS1/%8s(MDSK):", name);295		strlcat(state->pp_buf, tmp, PAGE_SIZE);296		/* disk is reserved minidisk */297		offset = label->cms.disk_offset * secperblk;298		size = (label->cms.block_count - 1) * secperblk;299	} else {300		snprintf(tmp, sizeof(tmp), "CMS1/%8s:", name);301		strlcat(state->pp_buf, tmp, PAGE_SIZE);302		/*303		 * Special case for FBA devices:304		 * If an FBA device is CMS formatted with blocksize > 512 byte305		 * and the DIAG discipline is used, then the CMS label is found306		 * in sector 1 instead of block 1. However, the partition is307		 * still supposed to start in block 2.308		 */309		if (labelsect == 1)310			offset = 2 * secperblk;311		else312			offset = labelsect + secperblk;313		size = label->cms.block_count * secperblk;314	}315 316	put_partition(state, 1, offset, size-offset);317	strlcat(state->pp_buf, "\n", PAGE_SIZE);318	return 1;319}320 321 322/*323 * This is the main function, called by check.c324 */325int ibm_partition(struct parsed_partitions *state)326{327	int (*fn)(struct gendisk *disk, dasd_information2_t *info);328	struct gendisk *disk = state->disk;329	struct block_device *bdev = disk->part0;330	int blocksize, res;331	loff_t offset, size;332	sector_t nr_sectors;333	dasd_information2_t *info;334	struct hd_geometry *geo;335	char type[DASD_VOL_TYPE_LEN + 1] = "";336	char name[DASD_VOL_ID_LEN + 1] = "";337	sector_t labelsect;338	union label_t *label;339 340	res = 0;341	if (!disk->fops->getgeo)342		goto out_exit;343	fn = symbol_get(dasd_biodasdinfo);344	blocksize = bdev_logical_block_size(bdev);345	if (blocksize <= 0)346		goto out_symbol;347	nr_sectors = bdev_nr_sectors(bdev);348	if (nr_sectors == 0)349		goto out_symbol;350	info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL);351	if (info == NULL)352		goto out_symbol;353	geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL);354	if (geo == NULL)355		goto out_nogeo;356	label = kmalloc(sizeof(union label_t), GFP_KERNEL);357	if (label == NULL)358		goto out_nolab;359	/* set start if not filled by getgeo function e.g. virtblk */360	geo->start = get_start_sect(bdev);361	if (disk->fops->getgeo(bdev, geo))362		goto out_freeall;363	if (!fn || fn(disk, info)) {364		kfree(info);365		info = NULL;366	}367 368	if (find_label(state, info, geo, blocksize, &labelsect, name, type, label)) {369		switch (get_label_by_type(type)) {370		case DASD_VOLLBL_TYPE_VOL1:371			res = find_vol1_partitions(state, geo, blocksize, name,372						   label);373			break;374		case DASD_VOLLBL_TYPE_LNX1:375			res = find_lnx1_partitions(state, geo, blocksize, name,376						   label, labelsect, nr_sectors,377						   info);378			break;379		case DASD_VOLLBL_TYPE_CMS1:380			res = find_cms1_partitions(state, geo, blocksize, name,381						   label, labelsect);382			break;383		}384	} else if (info) {385		/*386		 * ugly but needed for backward compatibility:387		 * If the block device is a DASD (i.e. BIODASDINFO2 works),388		 * then we claim it in any case, even though it has no valid389		 * label. If it has the LDL format, then we simply define a390		 * partition as if it had an LNX1 label.391		 */392		res = 1;393		if (info->format == DASD_FORMAT_LDL) {394			strlcat(state->pp_buf, "(nonl)", PAGE_SIZE);395			size = nr_sectors;396			offset = (info->label_block + 1) * (blocksize >> 9);397			put_partition(state, 1, offset, size-offset);398			strlcat(state->pp_buf, "\n", PAGE_SIZE);399		}400	} else401		res = 0;402 403out_freeall:404	kfree(label);405out_nolab:406	kfree(geo);407out_nogeo:408	kfree(info);409out_symbol:410	if (fn)411		symbol_put(dasd_biodasdinfo);412out_exit:413	return res;414}415