1 /* $NetBSD: disksubr.c,v 1.2 2002/02/19 17:09:42 wiz Exp $ */ 2 3 /* 4 * Copyright (c) 1998 Christopher G. Demetriou. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Christopher G. Demetriou 17 * for the NetBSD Project. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1982, 1986, 1988 Regents of the University of California. 35 * Copyright (c) 1995 Mark Brinicombe 36 * All rights reserved. 37 * 38 * Redistribution and use in source and binary forms, with or without 39 * modification, are permitted provided that the following conditions 40 * are met: 41 * 1. Redistributions of source code must retain the above copyright 42 * notice, this list of conditions and the following disclaimer. 43 * 2. Redistributions in binary form must reproduce the above copyright 44 * notice, this list of conditions and the following disclaimer in the 45 * documentation and/or other materials provided with the distribution. 46 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * from: @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91 67 */ 68 69 #include <sys/param.h> 70 #include <sys/systm.h> 71 #include <sys/buf.h> 72 #include <sys/dkbad.h> 73 #include <sys/disklabel.h> 74 #include <sys/syslog.h> 75 #include <sys/device.h> 76 #include <sys/disk.h> 77 78 /* 79 * Attempt to read a disk label from a device 80 * using the indicated strategy routine. 81 * The label must be partly set up before this: 82 * secpercyl, secsize and anything required for a block i/o read 83 * operation in the driver's strategy/start routines 84 * must be filled in before calling us. 85 * 86 * If dos partition table requested, attempt to load it and 87 * find disklabel inside a DOS partition. Also, if bad block 88 * table needed, attempt to extract it as well. Return buffer 89 * for use in signalling errors if requested. 90 * 91 * Returns null on success and an error string on failure. 92 */ 93 94 char * 95 readdisklabel(dev, strat, lp, osdep) 96 dev_t dev; 97 void (*strat) __P((struct buf *)); 98 struct disklabel *lp; 99 struct cpu_disklabel *osdep; 100 { 101 struct buf *bp; 102 struct disklabel *dlp; 103 char *msg = NULL; 104 int cyl, netbsdpartoff, i; 105 106 /* printf("Reading disclabel for %04x\n", dev);*/ 107 108 /* minimal requirements for archtypal disk label */ 109 110 if (lp->d_secsize == 0) 111 lp->d_secsize = DEV_BSIZE; 112 113 if (lp->d_secperunit == 0) 114 lp->d_secperunit = 0x1fffffff; 115 116 lp->d_npartitions = MAXPARTITIONS; 117 for (i = 0; i < MAXPARTITIONS; i++) { 118 if (i == RAW_PART) continue; 119 lp->d_partitions[i].p_offset = 0; 120 lp->d_partitions[i].p_fstype = FS_UNUSED; 121 lp->d_partitions[i].p_size = 0; 122 } 123 124 if (lp->d_partitions[RAW_PART].p_size == 0) { 125 lp->d_partitions[RAW_PART].p_fstype = FS_UNUSED; 126 lp->d_partitions[RAW_PART].p_offset = 0; 127 lp->d_partitions[RAW_PART].p_size = 0x1fffffff; 128 } 129 130 /* obtain buffer to probe drive with */ 131 132 bp = geteblk((int)lp->d_secsize); 133 134 /* request no partition relocation by driver on I/O operations */ 135 136 bp->b_dev = dev; 137 138 /* do netbsd partitions in the process of getting disklabel? */ 139 140 netbsdpartoff = 0; 141 cyl = LABELSECTOR / lp->d_secpercyl; 142 143 if (osdep) { 144 if (filecore_label_read(dev, strat,lp, osdep, &msg, &cyl, 145 &netbsdpartoff) || 146 mbr_label_read(dev, strat, lp, osdep, &msg, &cyl, 147 &netbsdpartoff)) { 148 if (msg != NULL) 149 goto done; 150 } else { 151 /* 152 * We didn't find anything we like; NetBSD native. 153 * netbsdpartoff and cyl should be unchanged. 154 */ 155 KASSERT(netbsdpartoff == 0); 156 KASSERT(cyl == (LABELSECTOR / lp->d_secpercyl)); 157 } 158 } 159 160 /* next, dig out disk label */ 161 162 /* printf("Reading disklabel addr=%08x\n", netbsdpartoff * DEV_BSIZE);*/ 163 164 bp->b_blkno = netbsdpartoff + LABELSECTOR; 165 bp->b_cylinder = bp->b_blkno / lp->d_secpercyl; 166 bp->b_bcount = lp->d_secsize; 167 bp->b_flags |= B_READ; 168 (*strat)(bp); 169 170 /* if successful, locate disk label within block and validate */ 171 172 if (biowait(bp)) { 173 msg = "disk label I/O error"; 174 goto done; 175 } 176 for (dlp = (struct disklabel *)bp->b_data; 177 dlp <= (struct disklabel *)(bp->b_data + lp->d_secsize - sizeof(*dlp)); 178 dlp = (struct disklabel *)((char *)dlp + sizeof(long))) { 179 if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) { 180 if (msg == NULL) 181 msg = "no disk label"; 182 } else if (dlp->d_npartitions > MAXPARTITIONS || 183 dkcksum(dlp) != 0) 184 msg = "disk label corrupted"; 185 else { 186 *lp = *dlp; 187 msg = NULL; 188 break; 189 } 190 } 191 192 if (msg) 193 goto done; 194 195 /* obtain bad sector table if requested and present */ 196 if (osdep && (lp->d_flags & D_BADSECT)) { 197 struct dkbad *bdp = &osdep->bad; 198 struct dkbad *db; 199 200 i = 0; 201 do { 202 /* read a bad sector table */ 203 bp->b_flags &= ~(B_DONE); 204 bp->b_flags |= B_READ; 205 bp->b_blkno = lp->d_secperunit - lp->d_nsectors + i; 206 if (lp->d_secsize > DEV_BSIZE) 207 bp->b_blkno *= lp->d_secsize / DEV_BSIZE; 208 else 209 bp->b_blkno /= DEV_BSIZE / lp->d_secsize; 210 bp->b_bcount = lp->d_secsize; 211 bp->b_cylinder = lp->d_ncylinders - 1; 212 (*strat)(bp); 213 214 /* if successful, validate, otherwise try another */ 215 if (biowait(bp)) { 216 msg = "bad sector table I/O error"; 217 } else { 218 db = (struct dkbad *)(bp->b_data); 219 #define DKBAD_MAGIC 0x4321 220 if (db->bt_mbz == 0 221 && db->bt_flag == DKBAD_MAGIC) { 222 msg = NULL; 223 *bdp = *db; 224 break; 225 } else 226 msg = "bad sector table corrupted"; 227 } 228 } while ((bp->b_flags & B_ERROR) && (i += 2) < 10 && 229 i < lp->d_nsectors); 230 } 231 232 done: 233 brelse(bp); 234 return (msg); 235 } 236 237 238 /* 239 * Check new disk label for sensibility 240 * before setting it. 241 */ 242 243 int 244 setdisklabel(olp, nlp, openmask, osdep) 245 struct disklabel *olp; 246 struct disklabel *nlp; 247 u_long openmask; 248 struct cpu_disklabel *osdep; 249 { 250 int i; 251 struct partition *opp, *npp; 252 253 /* sanity clause */ 254 255 if (nlp->d_secpercyl == 0 || nlp->d_secsize == 0 256 || (nlp->d_secsize % DEV_BSIZE) != 0) 257 return(EINVAL); 258 259 /* special case to allow disklabel to be invalidated */ 260 261 if (nlp->d_magic == 0xffffffff) { 262 *olp = *nlp; 263 return (0); 264 } 265 266 if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC 267 || dkcksum(nlp) != 0) 268 return (EINVAL); 269 270 /* XXX missing check if other acorn/dos partitions will be overwritten */ 271 272 while (openmask != 0) { 273 i = ffs(openmask) - 1; 274 openmask &= ~(1 << i); 275 if (nlp->d_npartitions <= i) 276 return (EBUSY); 277 opp = &olp->d_partitions[i]; 278 npp = &nlp->d_partitions[i]; 279 if (npp->p_offset != opp->p_offset || npp->p_size < opp->p_size) 280 return (EBUSY); 281 /* 282 * Copy internally-set partition information 283 * if new label doesn't include it. XXX 284 */ 285 if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) { 286 npp->p_fstype = opp->p_fstype; 287 npp->p_fsize = opp->p_fsize; 288 npp->p_frag = opp->p_frag; 289 npp->p_cpg = opp->p_cpg; 290 } 291 } 292 293 nlp->d_checksum = 0; 294 nlp->d_checksum = dkcksum(nlp); 295 *olp = *nlp; 296 return (0); 297 } 298 299 300 /* 301 * Write disk label back to device after modification. 302 */ 303 304 int 305 writedisklabel(dev, strat, lp, osdep) 306 dev_t dev; 307 void (*strat) __P((struct buf *)); 308 struct disklabel *lp; 309 struct cpu_disklabel *osdep; 310 { 311 struct buf *bp; 312 struct disklabel *dlp; 313 int cyl, netbsdpartoff; 314 int error = 0, rv; 315 316 /* get a buffer and initialize it */ 317 318 bp = geteblk((int)lp->d_secsize); 319 bp->b_dev = dev; 320 321 /* do netbsd partitions in the process of getting disklabel? */ 322 323 netbsdpartoff = 0; 324 cyl = LABELSECTOR / lp->d_secpercyl; 325 326 if (osdep) { 327 if ((rv = filecore_label_locate(dev, strat,lp, osdep, &cyl, 328 &netbsdpartoff)) != 0|| 329 (rv = mbr_label_locate(dev, strat, lp, osdep, &cyl, 330 &netbsdpartoff)) != 0) { 331 if (rv < 0) { 332 error = -rv; 333 goto done; 334 } 335 } else { 336 /* 337 * We didn't find anything we like; NetBSD native. 338 * netbsdpartoff and cyl should be unchanged. 339 */ 340 KASSERT(netbsdpartoff == 0); 341 KASSERT(cyl == (LABELSECTOR / lp->d_secpercyl)); 342 } 343 } 344 345 /* writelabel: */ 346 347 /* printf("writedisklabel: Reading disklabel addr=%08x\n", 348 netbsdpartoff * DEV_BSIZE);*/ 349 350 /* next, dig out disk label */ 351 352 bp->b_blkno = netbsdpartoff + LABELSECTOR; 353 bp->b_cylinder = cyl; 354 bp->b_bcount = lp->d_secsize; 355 bp->b_flags &= ~(B_DONE); 356 bp->b_flags |= B_READ; 357 (*strat)(bp); 358 359 /* if successful, locate disk label within block and validate */ 360 361 if ((error = biowait(bp))) 362 goto done; 363 for (dlp = (struct disklabel *)bp->b_data; 364 dlp <= (struct disklabel *)(bp->b_data + lp->d_secsize - sizeof(*dlp)); 365 dlp = (struct disklabel *)((char *)dlp + sizeof(long))) { 366 if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC && 367 dkcksum(dlp) == 0) { 368 *dlp = *lp; 369 bp->b_flags &= ~(B_READ|B_DONE); 370 bp->b_flags |= B_WRITE; 371 (*strat)(bp); 372 error = biowait(bp); 373 goto done; 374 } 375 } 376 377 error = ESRCH; 378 379 done: 380 brelse(bp); 381 return (error); 382 } 383 384 385 /* 386 * Determine the size of the transfer, and make sure it is 387 * within the boundaries of the partition. Adjust transfer 388 * if needed, and signal errors or early completion. 389 */ 390 int 391 bounds_check_with_label(bp, lp, wlabel) 392 struct buf *bp; 393 struct disklabel *lp; 394 int wlabel; 395 { 396 struct partition *p = lp->d_partitions + DISKPART(bp->b_dev); 397 int labelsector = lp->d_partitions[0].p_offset + LABELSECTOR; 398 int sz; 399 400 sz = howmany(bp->b_bcount, lp->d_secsize); 401 402 if (bp->b_blkno + sz > p->p_size) { 403 sz = p->p_size - bp->b_blkno; 404 if (sz == 0) { 405 /* If exactly at end of disk, return EOF. */ 406 bp->b_resid = bp->b_bcount; 407 goto done; 408 } 409 if (sz < 0) { 410 /* If past end of disk, return EINVAL. */ 411 bp->b_error = EINVAL; 412 goto bad; 413 } 414 /* Otherwise, truncate request. */ 415 bp->b_bcount = sz << DEV_BSHIFT; 416 } 417 418 /* Overwriting disk label? */ 419 if (bp->b_blkno + p->p_offset <= labelsector && 420 #if LABELSECTOR != 0 421 bp->b_blkno + p->p_offset + sz > labelsector && 422 #endif 423 (bp->b_flags & B_READ) == 0 && !wlabel) { 424 bp->b_error = EROFS; 425 goto bad; 426 } 427 428 /* calculate cylinder for disksort to order transfers with */ 429 bp->b_cylinder = (bp->b_blkno + p->p_offset) / 430 (lp->d_secsize / DEV_BSIZE) / lp->d_secpercyl; 431 return (1); 432 433 bad: 434 bp->b_flags |= B_ERROR; 435 done: 436 return (0); 437 } 438 439 /* End of disksubr.c */ 440