1// SPDX-License-Identifier: GPL-2.0 2/* 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, 2012 7 */ 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 a 29 * cyl-cyl-head-head structure 30 */ 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 a 47 * cyl-cyl-head-head-block structure 48 */ 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 64static int find_label(struct parsed_partitions *state, 65 dasd_information2_t *info, 66 struct hd_geometry *geo, 67 int blocksize, 68 sector_t *labelsect, 69 char name[], 70 char type[], 71 union label_t *label) 72{ 73 Sector sect; 74 unsigned char *data; 75 sector_t testsect[3]; 76 unsigned char temp[5]; 77 int found = 0; 78 int i, testcount; 79 80 /* There a three places where we may find a valid label: 81 * - on an ECKD disk it's block 2 82 * - on an FBA disk it's block 1 83 * - on an CMS formatted FBA disk it is sector 1, even if the block size 84 * is larger than 512 bytes (possible if the DIAG discipline is used) 85 * If we have a valid info structure, then we know exactly which case we 86 * have, otherwise we just search through all possebilities. 87 */ 88 if (info) { 89 if ((info->cu_type == 0x6310 && info->dev_type == 0x9336) || 90 (info->cu_type == 0x3880 && info->dev_type == 0x3370)) 91 testsect[0] = info->label_block; 92 else 93 testsect[0] = info->label_block * (blocksize >> 9); 94 testcount = 1; 95 } else { 96 testsect[0] = 1; 97 testsect[1] = (blocksize >> 9); 98 testsect[2] = 2 * (blocksize >> 9); 99 testcount = 3; 100 } 101 for (i = 0; i < testcount; ++i) { 102 data = read_part_sector(state, testsect[i], §); 103 if (data == NULL) 104 continue; 105 memcpy(label, data, sizeof(*label)); 106 memcpy(temp, data, 4); 107 temp[4] = 0; 108 EBCASC(temp, 4); 109 put_dev_sector(sect); 110 if (!strcmp(temp, "VOL1") || 111 !strcmp(temp, "LNX1") || 112 !strcmp(temp, "CMS1")) { 113 if (!strcmp(temp, "VOL1")) { 114 strncpy(type, label->vol.vollbl, 4); 115 strncpy(name, label->vol.volid, 6); 116 } else { 117 strncpy(type, label->lnx.vollbl, 4); 118 strncpy(name, label->lnx.volid, 6); 119 } 120 EBCASC(type, 4); 121 EBCASC(name, 6); 122 *labelsect = testsect[i]; 123 found = 1; 124 break; 125 } 126 } 127 if (!found) 128 memset(label, 0, sizeof(*label)); 129 130 return found; 131} 132 133static int find_vol1_partitions(struct parsed_partitions *state, 134 struct hd_geometry *geo, 135 int blocksize, 136 char name[], 137 union label_t *label) 138{ 139 sector_t blk; 140 int counter; 141 char tmp[64]; 142 Sector sect; 143 unsigned char *data; 144 loff_t offset, size; 145 struct vtoc_format1_label f1; 146 int secperblk; 147 148 snprintf(tmp, sizeof(tmp), "VOL1/%8s:", name); 149 strlcat(state->pp_buf, tmp, PAGE_SIZE); 150 /* 151 * get start of VTOC from the disk label and then search for format1 152 * and format8 labels 153 */ 154 secperblk = blocksize >> 9; 155 blk = cchhb2blk(&label->vol.vtoc, geo) + 1; 156 counter = 0; 157 data = read_part_sector(state, blk * secperblk, §); 158 while (data != NULL) { 159 memcpy(&f1, data, sizeof(struct vtoc_format1_label)); 160 put_dev_sector(sect); 161 /* skip FMT4 / FMT5 / FMT7 labels */ 162 if (f1.DS1FMTID == _ascebc['4'] 163 || f1.DS1FMTID == _ascebc['5'] 164 || f1.DS1FMTID == _ascebc['7'] 165 || f1.DS1FMTID == _ascebc['9']) { 166 blk++; 167 data = read_part_sector(state, blk * secperblk, §); 168 continue; 169 } 170 /* only FMT1 and 8 labels valid at this point */ 171 if (f1.DS1FMTID != _ascebc['1'] && 172 f1.DS1FMTID != _ascebc['8']) 173 break; 174 /* OK, we got valid partition data */ 175 offset = cchh2blk(&f1.DS1EXT1.llimit, geo); 176 size = cchh2blk(&f1.DS1EXT1.ulimit, geo) - 177 offset + geo->sectors; 178 offset *= secperblk; 179 size *= secperblk; 180 if (counter >= state->limit) 181 break; 182 put_partition(state, counter + 1, offset, size); 183 counter++; 184 blk++; 185 data = read_part_sector(state, blk * secperblk, §); 186 } 187 strlcat(state->pp_buf, "\n", PAGE_SIZE); 188 189 if (!data) 190 return -1; 191 192 return 1; 193} 194 195static int find_lnx1_partitions(struct parsed_partitions *state, 196 struct hd_geometry *geo, 197 int blocksize, 198 char name[], 199 union label_t *label, 200 sector_t labelsect, 201 loff_t i_size, 202 dasd_information2_t *info) 203{ 204 loff_t offset, geo_size, size; 205 char tmp[64]; 206 int secperblk; 207 208 snprintf(tmp, sizeof(tmp), "LNX1/%8s:", name); 209 strlcat(state->pp_buf, tmp, PAGE_SIZE); 210 secperblk = blocksize >> 9; 211 if (label->lnx.ldl_version == 0xf2) { 212 size = label->lnx.formatted_blocks * secperblk; 213 } else { 214 /* 215 * Formated w/o large volume support. If the sanity check 216 * 'size based on geo == size based on i_size' is true, then 217 * we can safely assume that we know the formatted size of 218 * the disk, otherwise we need additional information 219 * that we can only get from a real DASD device. 220 */ 221 geo_size = geo->cylinders * geo->heads 222 * geo->sectors * secperblk; 223 size = i_size >> 9; 224 if (size != geo_size) { 225 if (!info) { 226 strlcat(state->pp_buf, "\n", PAGE_SIZE); 227 return 1; 228 } 229 if (!strcmp(info->type, "ECKD")) 230 if (geo_size < size) 231 size = geo_size; 232 /* else keep size based on i_size */ 233 } 234 } 235 /* first and only partition starts in the first block after the label */ 236 offset = labelsect + secperblk; 237 put_partition(state, 1, offset, size - offset); 238 strlcat(state->pp_buf, "\n", PAGE_SIZE); 239 return 1; 240} 241 242static int find_cms1_partitions(struct parsed_partitions *state, 243 struct hd_geometry *geo, 244 int blocksize, 245 char name[], 246 union label_t *label, 247 sector_t labelsect) 248{ 249 loff_t offset, size; 250 char tmp[64]; 251 int secperblk; 252 253 /* 254 * VM style CMS1 labeled disk 255 */ 256 blocksize = label->cms.block_size; 257 secperblk = blocksize >> 9; 258 if (label->cms.disk_offset != 0) { 259 snprintf(tmp, sizeof(tmp), "CMS1/%8s(MDSK):", name); 260 strlcat(state->pp_buf, tmp, PAGE_SIZE); 261 /* disk is reserved minidisk */ 262 offset = label->cms.disk_offset * secperblk; 263 size = (label->cms.block_count - 1) * secperblk; 264 } else { 265 snprintf(tmp, sizeof(tmp), "CMS1/%8s:", name); 266 strlcat(state->pp_buf, tmp, PAGE_SIZE); 267 /* 268 * Special case for FBA devices: 269 * If an FBA device is CMS formatted with blocksize > 512 byte 270 * and the DIAG discipline is used, then the CMS label is found 271 * in sector 1 instead of block 1. However, the partition is 272 * still supposed to start in block 2. 273 */ 274 if (labelsect == 1) 275 offset = 2 * secperblk; 276 else 277 offset = labelsect + secperblk; 278 size = label->cms.block_count * secperblk; 279 } 280 281 put_partition(state, 1, offset, size-offset); 282 strlcat(state->pp_buf, "\n", PAGE_SIZE); 283 return 1; 284} 285 286 287/* 288 * This is the main function, called by check.c 289 */ 290int ibm_partition(struct parsed_partitions *state) 291{ 292 int (*fn)(struct gendisk *disk, dasd_information2_t *info); 293 struct block_device *bdev = state->bdev; 294 struct gendisk *disk = bdev->bd_disk; 295 int blocksize, res; 296 loff_t i_size, offset, size; 297 dasd_information2_t *info; 298 struct hd_geometry *geo; 299 char type[5] = {0,}; 300 char name[7] = {0,}; 301 sector_t labelsect; 302 union label_t *label; 303 304 res = 0; 305 if (!disk->fops->getgeo) 306 goto out_exit; 307 fn = symbol_get(dasd_biodasdinfo); 308 blocksize = bdev_logical_block_size(bdev); 309 if (blocksize <= 0) 310 goto out_symbol; 311 i_size = i_size_read(bdev->bd_inode); 312 if (i_size == 0) 313 goto out_symbol; 314 info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL); 315 if (info == NULL) 316 goto out_symbol; 317 geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL); 318 if (geo == NULL) 319 goto out_nogeo; 320 label = kmalloc(sizeof(union label_t), GFP_KERNEL); 321 if (label == NULL) 322 goto out_nolab; 323 /* set start if not filled by getgeo function e.g. virtblk */ 324 geo->start = get_start_sect(bdev); 325 if (disk->fops->getgeo(bdev, geo)) 326 goto out_freeall; 327 if (!fn || fn(disk, info)) { 328 kfree(info); 329 info = NULL; 330 } 331 332 if (find_label(state, info, geo, blocksize, &labelsect, name, type, 333 label)) { 334 if (!strncmp(type, "VOL1", 4)) { 335 res = find_vol1_partitions(state, geo, blocksize, name, 336 label); 337 } else if (!strncmp(type, "LNX1", 4)) { 338 res = find_lnx1_partitions(state, geo, blocksize, name, 339 label, labelsect, i_size, 340 info); 341 } else if (!strncmp(type, "CMS1", 4)) { 342 res = find_cms1_partitions(state, geo, blocksize, name, 343 label, labelsect); 344 } 345 } else if (info) { 346 /* 347 * ugly but needed for backward compatibility: 348 * If the block device is a DASD (i.e. BIODASDINFO2 works), 349 * then we claim it in any case, even though it has no valid 350 * label. If it has the LDL format, then we simply define a 351 * partition as if it had an LNX1 label. 352 */ 353 res = 1; 354 if (info->format == DASD_FORMAT_LDL) { 355 strlcat(state->pp_buf, "(nonl)", PAGE_SIZE); 356 size = i_size >> 9; 357 offset = (info->label_block + 1) * (blocksize >> 9); 358 put_partition(state, 1, offset, size-offset); 359 strlcat(state->pp_buf, "\n", PAGE_SIZE); 360 } 361 } else 362 res = 0; 363 364out_freeall: 365 kfree(label); 366out_nolab: 367 kfree(geo); 368out_nogeo: 369 kfree(info); 370out_symbol: 371 if (fn) 372 symbol_put(dasd_biodasdinfo); 373out_exit: 374 return res; 375} 376