1 /* $NetBSD: disksubr.c,v 1.33 2008/01/02 11:48:32 ad Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1988 Regents of the University of California. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: disksubr.c,v 1.33 2008/01/02 11:48:32 ad Exp $"); 36 37 #include "opt_compat_netbsd.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/buf.h> 42 #include <sys/disklabel.h> 43 #include <sys/syslog.h> 44 #include <sys/disk.h> 45 46 /* get rid of DEV_BSIZE dependency */ 47 #define DEF_BSIZE DEV_BSIZE /* default sector size = 512 */ 48 49 static void parttbl_consistency_check(struct disklabel *, 50 struct dos_partition *); 51 52 53 /* 54 * Attempt to read a disk label from a device 55 * using the indicated strategy routine. 56 * The label must be partly set up before this: 57 * secpercyl, secsize and anything required for a block i/o read 58 * operation in the driver's strategy/start routines 59 * must be filled in before calling us. 60 * 61 * Returns null on success and an error string on failure. 62 */ 63 const char * 64 readdisklabel(dev_t dev, void (*strat)(struct buf *), 65 struct disklabel *lp, struct cpu_disklabel *osdep) 66 { 67 struct dos_partition *dp = 0; 68 struct dkbad *bdp = &osdep->bad; 69 struct buf *bp; 70 struct disklabel *dlp; 71 const char *msg = NULL; 72 int i, labelsz; 73 74 if (osdep) 75 dp = osdep->dosparts; 76 /* minimal requirements for archtypal disk label */ 77 if (lp->d_secsize == 0) 78 lp->d_secsize = DEF_BSIZE; 79 if (lp->d_secperunit == 0) 80 lp->d_secperunit = 0x1fffffff; 81 if (lp->d_secpercyl == 0) 82 lp->d_secpercyl = 0x1fffffff; 83 lp->d_npartitions = RAW_PART + 1; 84 for (i = 0; i < RAW_PART; i++) { 85 lp->d_partitions[i].p_size = 0; 86 lp->d_partitions[i].p_offset = 0; 87 } 88 if (lp->d_partitions[0].p_size == 0) 89 lp->d_partitions[0].p_size = 0x1fffffff; 90 lp->d_partitions[0].p_offset = 0; 91 92 /* get a buffer and initialize it */ 93 bp = geteblk((int)lp->d_secsize); 94 bp->b_dev = dev; 95 96 /* read BSD disklabel first */ 97 bp->b_blkno = LABELSECTOR; 98 bp->b_cylinder = LABELSECTOR/lp->d_secpercyl; 99 labelsz = howmany(LABELOFFSET+sizeof(struct disklabel), lp->d_secsize) 100 * lp->d_secsize; 101 bp->b_bcount = labelsz; /* to support < 512B/sector disks */ 102 bp->b_flags |= B_READ; 103 (*strat)(bp); 104 105 /* if successful, locate disk label within block and validate */ 106 if (biowait(bp)) { 107 msg = "disk label I/O error"; 108 goto dodospart; 109 } 110 for (dlp = (struct disklabel *)bp->b_data; 111 dlp <= (struct disklabel *) 112 ((char *)bp->b_data + labelsz - sizeof(*dlp)); 113 dlp = (struct disklabel *)((uint8_t *)dlp + sizeof(long))) { 114 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) { 115 if (msg == NULL) 116 msg = "no disk label"; 117 } else if (dlp->d_npartitions > MAXPARTITIONS || 118 dkcksum(dlp) != 0) 119 msg = "disk label corrupted"; 120 else { 121 *lp = *dlp; 122 msg = NULL; 123 break; 124 } 125 } 126 127 dodospart: 128 /* next do the Human68k-style partition table */ 129 /* Human68k does not support > 2048B/sector devices (?) */ 130 if (lp->d_secsize >= 2048) { 131 if (msg) 132 goto done; 133 goto dobadsect; 134 } 135 bp->b_blkno = DOSPARTOFF * DEF_BSIZE / lp->d_secsize; 136 /* DOSPARTOFF in DEV_BSIZE unit */ 137 bp->b_cylinder = DOSBBSECTOR / lp->d_secpercyl; 138 labelsz = howmany(sizeof(struct cpu_disklabel), 139 lp->d_secsize) * lp->d_secsize; 140 bp->b_bcount = labelsz; /* to support < 512B/sector disks */ 141 bp->b_oflags &= ~(BO_DONE); 142 (*strat)(bp); 143 144 /* if successful, wander through Human68k partition table */ 145 if (biowait(bp)) 146 goto done; 147 if (strncmp(bp->b_data, "X68K", 4) != 0) { 148 /* Human68k-style partition table does not exist */ 149 if (msg) 150 goto done; 151 goto dobadsect; 152 } 153 154 /* XXX how do we check veracity/bounds of this? */ 155 if (dp) 156 memcpy(dp, (char *)bp->b_data + sizeof(*dp) /*DOSPARTOFF*/, 157 NDOSPART * sizeof(*dp)); 158 else 159 dp = (void *)((char *)bp->b_data + sizeof(*dp) /*DOSPARTOFF*/); 160 161 /* if BSD disklabel does not exist, fall back to Human68k partition */ 162 if (msg != NULL) { 163 msg = NULL; 164 lp->d_bbsize = 8192; 165 lp->d_sbsize = 2048; 166 for (i = 0; i < NDOSPART; i++, dp++) 167 /* is this ours? */ 168 if (dp->dp_size) { 169 u_char fstype; 170 int part = i + (i < RAW_PART ? 0 : 1); 171 int start = dp->dp_start * 2; 172 int size = dp->dp_size * 2; 173 174 /* update disklabel with details */ 175 lp->d_partitions[part].p_size = size; 176 lp->d_partitions[part].p_offset = start; 177 /* get partition type */ 178 #ifndef COMPAT_10 179 if (dp->dp_flag == 1) 180 fstype = FS_UNUSED; 181 else 182 #endif 183 if (!memcmp(dp->dp_typname, "Human68k", 8)) 184 fstype = FS_MSDOS; 185 else if (!memcmp(dp->dp_typname, 186 "BSD ffs ", 8)) 187 fstype = FS_BSDFFS; 188 else if (!memcmp(dp->dp_typname, 189 "BSD lfs ", 8)) 190 fstype = FS_BSDLFS; 191 else if (!memcmp(dp->dp_typname, 192 "BSD swap", 8)) 193 fstype = FS_SWAP; 194 #ifndef COMPAT_14 195 else if (part == 1) 196 fstype = FS_SWAP; 197 #endif 198 else 199 fstype = FS_BSDFFS; /* XXX */ 200 lp->d_partitions[part].p_fstype = fstype; /* XXX */ 201 if (lp->d_npartitions <= part) 202 lp->d_npartitions = part + 1; 203 } 204 } else { 205 parttbl_consistency_check(lp, dp); 206 } 207 208 dobadsect: 209 /* obtain bad sector table if requested and present */ 210 if (bdp && (lp->d_flags & D_BADSECT)) { 211 struct dkbad *db; 212 213 i = 0; 214 do { 215 /* read a bad sector table */ 216 bp->b_oflags &= ~(BO_DONE); 217 bp->b_flags |= B_READ; 218 bp->b_blkno = lp->d_secperunit - lp->d_nsectors + i; 219 if (lp->d_secsize > DEF_BSIZE) 220 bp->b_blkno *= lp->d_secsize / DEF_BSIZE; 221 else 222 bp->b_blkno /= DEF_BSIZE / lp->d_secsize; 223 bp->b_bcount = lp->d_secsize; 224 bp->b_cylinder = lp->d_ncylinders - 1; 225 (*strat)(bp); 226 227 /* if successful, validate, otherwise try another */ 228 if (biowait(bp)) { 229 msg = "bad sector table I/O error"; 230 } else { 231 db = (struct dkbad *)(bp->b_data); 232 #define DKBAD_MAGIC 0x4321 233 if (db->bt_mbz == 0 234 && db->bt_flag == DKBAD_MAGIC) { 235 msg = NULL; 236 *bdp = *db; 237 break; 238 } else 239 msg = "bad sector table corrupted"; 240 } 241 } while (bp->b_error != 0 && (i += 2) < 10 && 242 i < lp->d_nsectors); 243 } 244 245 done: 246 brelse(bp, 0); 247 return (msg); 248 } 249 250 /* 251 * Check new disk label for sensibility 252 * before setting it. 253 */ 254 int 255 setdisklabel(struct disklabel *olp, struct disklabel *nlp, u_long openmask, 256 struct cpu_disklabel *osdep) 257 { 258 int i; 259 struct partition *opp, *npp; 260 261 /* sanity clause */ 262 if (nlp->d_secpercyl == 0 || nlp->d_secsize == 0 263 /*|| (nlp->d_secsize % DEV_BSIZE) != 0*/) 264 return(EINVAL); 265 266 /* special case to allow disklabel to be invalidated */ 267 if (nlp->d_magic == 0xffffffff) { 268 *olp = *nlp; 269 return (0); 270 } 271 272 if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC || 273 dkcksum(nlp) != 0) 274 return (EINVAL); 275 276 if (osdep) 277 parttbl_consistency_check(nlp, osdep->dosparts); 278 /* XXX missing check if other dos partitions will be overwritten */ 279 280 while (openmask != 0) { 281 i = ffs(openmask) - 1; 282 openmask &= ~(1 << i); 283 if (nlp->d_npartitions <= i) 284 return (EBUSY); 285 opp = &olp->d_partitions[i]; 286 npp = &nlp->d_partitions[i]; 287 if (npp->p_offset != opp->p_offset || npp->p_size < opp->p_size) 288 return (EBUSY); 289 /* 290 * Copy internally-set partition information 291 * if new label doesn't include it. XXX 292 */ 293 if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) { 294 npp->p_fstype = opp->p_fstype; 295 npp->p_fsize = opp->p_fsize; 296 npp->p_frag = opp->p_frag; 297 npp->p_cpg = opp->p_cpg; 298 } 299 } 300 nlp->d_checksum = 0; 301 nlp->d_checksum = dkcksum(nlp); 302 *olp = *nlp; 303 return (0); 304 } 305 306 /* 307 * Write disk label back to device after modification. 308 */ 309 int 310 writedisklabel(dev_t dev, void (*strat)(struct buf *), 311 struct disklabel *lp, struct cpu_disklabel *osdep) 312 { 313 struct dos_partition *dp = 0; 314 struct buf *bp; 315 struct disklabel *dlp; 316 int error, labelsz, i; 317 const char *np; 318 319 if (osdep) 320 dp = osdep->dosparts; 321 /* sanity clause */ 322 if (lp->d_secpercyl == 0 || lp->d_secsize == 0 323 /*|| (lp->d_secsize % DEF_BSIZE) != 0*/) 324 return(EINVAL); 325 if (dp) 326 parttbl_consistency_check(lp, dp); 327 328 /* get a buffer and initialize it */ 329 bp = geteblk((int)lp->d_secsize); 330 bp->b_dev = dev; 331 332 /* attempt to write BSD disklabel first */ 333 bp->b_blkno = LABELSECTOR; 334 bp->b_cylinder = LABELSECTOR / lp->d_secpercyl; 335 labelsz = howmany(LABELOFFSET+sizeof(struct disklabel), lp->d_secsize) 336 * lp->d_secsize; 337 bp->b_bcount = labelsz; /* to support < 512B/sector disks */ 338 bp->b_flags |= B_READ; 339 (*strat)(bp); 340 341 /* if successful, locate disk label within block and validate */ 342 if (biowait(bp)) 343 goto dodospart; 344 error = ESRCH; 345 for (dlp = (struct disklabel *)bp->b_data; 346 dlp <= (struct disklabel *) 347 ((char *)bp->b_data + labelsz - sizeof(*dlp)); 348 dlp = (struct disklabel *)((char *)dlp + sizeof(long))) { 349 if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC && 350 dkcksum(dlp) == 0) { 351 *dlp = *lp; 352 bp->b_oflags &= ~(BO_DONE); 353 bp->b_flags &= ~(B_READ); 354 bp->b_flags |= B_WRITE; 355 (*strat)(bp); 356 error = biowait(bp); 357 break; 358 } 359 } 360 361 /* do dos partitions in the process of getting disklabel? */ 362 if (error) { 363 dodospart: 364 if (lp->d_secsize >= 2048) { 365 error = ESRCH; 366 goto done; 367 } 368 #if 0 /* there is no mark on floppies */ 369 /* read the x68k disk magic */ 370 bp->b_blkno = DOSBBSECTOR; 371 bp->b_bcount = lp->d_secsize; 372 bp->b_oflags &= ~(BO_DONE); 373 bp->b_flags |= B_READ; 374 bp->b_cylinder = DOSBBSECTOR / lp->d_secpercyl; 375 (*strat)(bp); 376 if ((error = biowait(bp)) || memcmp(bp->b_data, "X68SCSI1", 8)) 377 printf("warning: disk not marked for x68k"); 378 #endif 379 380 /* read the partition table */ 381 bp->b_blkno = DOSPARTOFF; 382 labelsz = howmany(sizeof(struct cpu_disklabel), 383 lp->d_secsize) * lp->d_secsize; 384 bp->b_bcount = labelsz; 385 bp->b_oflags &= ~(BO_DONE); 386 bp->b_flags |= B_READ; 387 bp->b_cylinder = DOSPARTOFF / lp->d_secpercyl; 388 (*strat)(bp); 389 390 if ((error = biowait(bp)) == 0) { 391 /* XXX how do we check veracity/bounds of this? */ 392 dp = (struct dos_partition *)bp->b_data + 1; 393 for (i = 0; i < NDOSPART; i++, dp++) { 394 int part = i + (i < RAW_PART ? 0 : 1); 395 int start, size; 396 397 start = lp->d_partitions[part].p_offset >> 1; 398 size = lp->d_partitions[part].p_size >> 1; 399 400 switch (lp->d_partitions[part].p_fstype) { 401 case FS_MSDOS: 402 np = "Human68k"; 403 dp->dp_flag = 0; /* autoboot */ 404 break; 405 406 case FS_SWAP: 407 np = "BSD swap"; 408 dp->dp_flag = 2; /* in use */ 409 break; 410 411 case FS_BSDFFS: 412 np = "BSD ffs "; 413 if (part == 0) 414 dp->dp_flag = 0; /* autoboot */ 415 else 416 dp->dp_flag = 2; /* in use */ 417 break; 418 419 case FS_BSDLFS: 420 np = "BSD lfs "; 421 if (part == 0) 422 dp->dp_flag = 0; /* autoboot */ 423 else 424 dp->dp_flag = 2; /* in use */ 425 break; 426 427 case FS_UNUSED: 428 np = "\0\0\0\0\0\0\0\0"; 429 start = size = 0; 430 if (part < lp->d_npartitions) { 431 dp->dp_flag = 1; 432 } else { 433 dp->dp_flag = 0; 434 } 435 break; 436 437 default: 438 /* XXX OS-9, MINIX etc. */ 439 continue; 440 } 441 memcpy(dp->dp_typname, np, 8); 442 dp->dp_start = start; 443 dp->dp_size = size; 444 } 445 bp->b_oflags &= ~(BO_DONE); 446 bp->b_flags &= ~(B_READ); 447 bp->b_flags |= B_WRITE; 448 (*strat)(bp); 449 error = biowait(bp); 450 } 451 } 452 453 #ifdef maybe 454 /* disklabel in appropriate location? */ 455 if (lp->d_partitions[0].p_offset != 0 456 && lp->d_partitions[0].p_offset != dospartoff) { 457 error = EXDEV; 458 goto done; 459 } 460 #endif 461 462 done: 463 brelse(bp, 0); 464 return (error); 465 } 466 467 static void 468 parttbl_consistency_check(struct disklabel *lp, struct dos_partition *dp) 469 { 470 int i, j; 471 int f = (lp->d_secsize >= 1024) ? lp->d_secsize/1024 : 1; 472 int g = (lp->d_secsize >= 1024) ? 1 : 1024/lp->d_secsize; 473 474 /* 1. overlapping check on partition table */ 475 for (i = 0; i < NDOSPART; i++) { 476 if (dp[i].dp_size == 0) 477 continue; 478 for (j = i+1; j < NDOSPART; j++) { 479 if (dp[j].dp_size == 0) 480 continue; 481 if (((dp[i].dp_start <= dp[j].dp_start) && 482 (dp[i].dp_start + dp[i].dp_size > dp[j].dp_start))|| 483 ((dp[j].dp_start <= dp[i].dp_start) && 484 (dp[j].dp_start + dp[j].dp_size > dp[i].dp_start))) { 485 printf("warning: Human68k partition %d and %d" 486 " are overlapping\n", i+1, j+1); 487 return; 488 } 489 } 490 } 491 492 /* 2. scan disklabel partitions */ 493 #define bp lp->d_partitions 494 for (i = 0; i < lp->d_npartitions; i++) { 495 int c = 0; 496 497 if (lp->d_partitions[i].p_fstype == FS_UNUSED || 498 lp->d_partitions[i].p_size == 0) 499 continue; 500 for (j = 0; j < NDOSPART; j++) { 501 if (dp[j].dp_size == 0) 502 continue; 503 if ((bp[i].p_offset * f < (dp[j].dp_start + dp[j].dp_size) * g) && 504 ((bp[i].p_offset + bp[i].p_size) * f >= (dp[j].dp_start + dp[j].dp_size) * g)) 505 c++; 506 if ((bp[i].p_offset * f > dp[j].dp_start * g) && 507 ((bp[i].p_offset + bp[i].p_size) * f < (dp[j].dp_start + dp[j].dp_size) * g)) 508 c++; 509 if ((bp[i].p_offset * f >= dp[j].dp_start * g) && 510 ((bp[i].p_offset + bp[i].p_size) * f < dp[j].dp_start * g)) 511 c++; 512 } 513 if (c > 1) 514 printf ("warning: partition %c spans for 2 or more" 515 " partitions in Human68k partition table.\n", 516 i+'a'); 517 } 518 #undef bp 519 520 /* more checks? */ 521 } 522