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 21 union 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 */ 31 static 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 */ 49 static 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 4 66 #define DASD_VOL_ID_LEN 6 67 68 /* Volume Label Types */ 69 #define DASD_VOLLBL_TYPE_VOL1 0 70 #define DASD_VOLLBL_TYPE_LNX1 1 71 #define DASD_VOLLBL_TYPE_CMS1 2 72 73 struct dasd_vollabel { 74 char *type; 75 int idx; 76 }; 77 78 static 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 93 static 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 } 104 105 static 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 2 121 * - on an FBA disk it's block 1 122 * - on an CMS formatted FBA disk it is sector 1, even if the block size 123 * 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 we 125 * 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 else 132 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], §); 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 } 167 168 static 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 Sector sect; 177 unsigned char *data; 178 loff_t offset, size; 179 struct vtoc_format1_label f1; 180 int secperblk; 181 182 seq_buf_printf(&state->pp_buf, "VOL1/%8s:", name); 183 /* 184 * get start of VTOC from the disk label and then search for format1 185 * and format8 labels 186 */ 187 secperblk = blocksize >> 9; 188 blk = cchhb2blk(&label->vol.vtoc, geo) + 1; 189 counter = 0; 190 data = read_part_sector(state, blk * secperblk, §); 191 while (data != NULL) { 192 memcpy(&f1, data, sizeof(struct vtoc_format1_label)); 193 put_dev_sector(sect); 194 /* skip FMT4 / FMT5 / FMT7 labels */ 195 if (f1.DS1FMTID == _ascebc['4'] 196 || f1.DS1FMTID == _ascebc['5'] 197 || f1.DS1FMTID == _ascebc['7'] 198 || f1.DS1FMTID == _ascebc['9']) { 199 blk++; 200 data = read_part_sector(state, blk * secperblk, §); 201 continue; 202 } 203 /* only FMT1 and 8 labels valid at this point */ 204 if (f1.DS1FMTID != _ascebc['1'] && 205 f1.DS1FMTID != _ascebc['8']) 206 break; 207 /* OK, we got valid partition data */ 208 offset = cchh2blk(&f1.DS1EXT1.llimit, geo); 209 size = cchh2blk(&f1.DS1EXT1.ulimit, geo) - 210 offset + geo->sectors; 211 offset *= secperblk; 212 size *= secperblk; 213 if (counter >= state->limit) 214 break; 215 put_partition(state, counter + 1, offset, size); 216 counter++; 217 blk++; 218 data = read_part_sector(state, blk * secperblk, §); 219 } 220 seq_buf_puts(&state->pp_buf, "\n"); 221 222 if (!data) 223 return -1; 224 225 return 1; 226 } 227 228 static int find_lnx1_partitions(struct parsed_partitions *state, 229 struct hd_geometry *geo, 230 int blocksize, 231 char name[], 232 union label_t *label, 233 sector_t labelsect, 234 sector_t nr_sectors, 235 dasd_information2_t *info) 236 { 237 loff_t offset, geo_size, size; 238 int secperblk; 239 240 seq_buf_printf(&state->pp_buf, "LNX1/%8s:", name); 241 secperblk = blocksize >> 9; 242 if (label->lnx.ldl_version == 0xf2) { 243 size = label->lnx.formatted_blocks * secperblk; 244 } else { 245 /* 246 * Formated w/o large volume support. If the sanity check 247 * 'size based on geo == size based on nr_sectors' is true, then 248 * we can safely assume that we know the formatted size of 249 * the disk, otherwise we need additional information 250 * that we can only get from a real DASD device. 251 */ 252 geo_size = geo->cylinders * geo->heads 253 * geo->sectors * secperblk; 254 size = nr_sectors; 255 if (size != geo_size) { 256 if (!info) { 257 seq_buf_puts(&state->pp_buf, "\n"); 258 return 1; 259 } 260 if (!strcmp(info->type, "ECKD")) 261 if (geo_size < size) 262 size = geo_size; 263 /* else keep size based on nr_sectors */ 264 } 265 } 266 /* first and only partition starts in the first block after the label */ 267 offset = labelsect + secperblk; 268 put_partition(state, 1, offset, size - offset); 269 seq_buf_puts(&state->pp_buf, "\n"); 270 return 1; 271 } 272 273 static int find_cms1_partitions(struct parsed_partitions *state, 274 struct hd_geometry *geo, 275 int blocksize, 276 char name[], 277 union label_t *label, 278 sector_t labelsect) 279 { 280 loff_t offset, size; 281 int secperblk; 282 283 /* 284 * VM style CMS1 labeled disk 285 */ 286 blocksize = label->cms.block_size; 287 secperblk = blocksize >> 9; 288 if (label->cms.disk_offset != 0) { 289 seq_buf_printf(&state->pp_buf, "CMS1/%8s(MDSK):", name); 290 /* disk is reserved minidisk */ 291 offset = label->cms.disk_offset * secperblk; 292 size = (label->cms.block_count - 1) * secperblk; 293 } else { 294 seq_buf_printf(&state->pp_buf, "CMS1/%8s:", name); 295 /* 296 * Special case for FBA devices: 297 * If an FBA device is CMS formatted with blocksize > 512 byte 298 * and the DIAG discipline is used, then the CMS label is found 299 * in sector 1 instead of block 1. However, the partition is 300 * still supposed to start in block 2. 301 */ 302 if (labelsect == 1) 303 offset = 2 * secperblk; 304 else 305 offset = labelsect + secperblk; 306 size = label->cms.block_count * secperblk; 307 } 308 309 put_partition(state, 1, offset, size-offset); 310 seq_buf_puts(&state->pp_buf, "\n"); 311 return 1; 312 } 313 314 315 /* 316 * This is the main function, called by check.c 317 */ 318 int ibm_partition(struct parsed_partitions *state) 319 { 320 int (*fn)(struct gendisk *disk, dasd_information2_t *info); 321 struct gendisk *disk = state->disk; 322 struct block_device *bdev = disk->part0; 323 int blocksize, res; 324 loff_t offset, size; 325 sector_t nr_sectors; 326 dasd_information2_t *info; 327 struct hd_geometry *geo; 328 char type[DASD_VOL_TYPE_LEN + 1] = ""; 329 char name[DASD_VOL_ID_LEN + 1] = ""; 330 sector_t labelsect; 331 union label_t *label; 332 333 res = 0; 334 if (!disk->fops->getgeo) 335 goto out_exit; 336 fn = symbol_get(dasd_biodasdinfo); 337 blocksize = bdev_logical_block_size(bdev); 338 if (blocksize <= 0) 339 goto out_symbol; 340 nr_sectors = bdev_nr_sectors(bdev); 341 if (nr_sectors == 0) 342 goto out_symbol; 343 info = kmalloc_obj(dasd_information2_t); 344 if (info == NULL) 345 goto out_symbol; 346 geo = kmalloc_obj(struct hd_geometry); 347 if (geo == NULL) 348 goto out_nogeo; 349 label = kmalloc_obj(union label_t); 350 if (label == NULL) 351 goto out_nolab; 352 /* set start if not filled by getgeo function e.g. virtblk */ 353 geo->start = get_start_sect(bdev); 354 if (disk->fops->getgeo(disk, geo)) 355 goto out_freeall; 356 if (!fn || fn(disk, info)) { 357 kfree(info); 358 info = NULL; 359 } 360 361 if (find_label(state, info, geo, blocksize, &labelsect, name, type, label)) { 362 switch (get_label_by_type(type)) { 363 case DASD_VOLLBL_TYPE_VOL1: 364 res = find_vol1_partitions(state, geo, blocksize, name, 365 label); 366 break; 367 case DASD_VOLLBL_TYPE_LNX1: 368 res = find_lnx1_partitions(state, geo, blocksize, name, 369 label, labelsect, nr_sectors, 370 info); 371 break; 372 case DASD_VOLLBL_TYPE_CMS1: 373 res = find_cms1_partitions(state, geo, blocksize, name, 374 label, labelsect); 375 break; 376 } 377 } else if (info) { 378 /* 379 * ugly but needed for backward compatibility: 380 * If the block device is a DASD (i.e. BIODASDINFO2 works), 381 * then we claim it in any case, even though it has no valid 382 * label. If it has the LDL format, then we simply define a 383 * partition as if it had an LNX1 label. 384 */ 385 res = 1; 386 if (info->format == DASD_FORMAT_LDL) { 387 seq_buf_puts(&state->pp_buf, "(nonl)"); 388 size = nr_sectors; 389 offset = (info->label_block + 1) * (blocksize >> 9); 390 put_partition(state, 1, offset, size-offset); 391 seq_buf_puts(&state->pp_buf, "\n"); 392 } 393 } else 394 res = 0; 395 396 out_freeall: 397 kfree(label); 398 out_nolab: 399 kfree(geo); 400 out_nogeo: 401 kfree(info); 402 out_symbol: 403 if (fn) 404 symbol_put(dasd_biodasdinfo); 405 out_exit: 406 return res; 407 } 408