1 /* 2 * Copyright (c) 2003,2004 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 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 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * ---------------------------------------------------------------------------- 35 * "THE BEER-WARE LICENSE" (Revision 42): 36 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you 37 * can do whatever you want with this stuff. If we meet some day, and you think 38 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 39 * ---------------------------------------------------------------------------- 40 * 41 * Copyright (c) 1982, 1986, 1988, 1993 42 * The Regents of the University of California. All rights reserved. 43 * (c) UNIX System Laboratories, Inc. 44 * All or some portions of this file are derived from material licensed 45 * to the University of California by American Telephone and Telegraph 46 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 47 * the permission of UNIX System Laboratories, Inc. 48 * 49 * Redistribution and use in source and binary forms, with or without 50 * modification, are permitted provided that the following conditions 51 * are met: 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 2. Redistributions in binary form must reproduce the above copyright 55 * notice, this list of conditions and the following disclaimer in the 56 * documentation and/or other materials provided with the distribution. 57 * 3. All advertising materials mentioning features or use of this software 58 * must display the following acknowledgement: 59 * This product includes software developed by the University of 60 * California, Berkeley and its contributors. 61 * 4. Neither the name of the University nor the names of its contributors 62 * may be used to endorse or promote products derived from this software 63 * without specific prior written permission. 64 * 65 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 66 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 67 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 68 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 69 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 70 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 71 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 72 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 73 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 74 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 75 * SUCH DAMAGE. 76 * 77 * @(#)ufs_disksubr.c 8.5 (Berkeley) 1/21/94 78 * $FreeBSD: src/sys/kern/subr_disk.c,v 1.20.2.6 2001/10/05 07:14:57 peter Exp $ 79 * $FreeBSD: src/sys/ufs/ufs/ufs_disksubr.c,v 1.44.2.3 2001/03/05 05:42:19 obrien Exp $ 80 * $DragonFly: src/sys/kern/subr_disk.c,v 1.40 2008/06/05 18:06:32 swildner Exp $ 81 */ 82 83 #include <sys/param.h> 84 #include <sys/systm.h> 85 #include <sys/kernel.h> 86 #include <sys/proc.h> 87 #include <sys/sysctl.h> 88 #include <sys/buf.h> 89 #include <sys/conf.h> 90 #include <sys/diskslice.h> 91 #include <sys/disk.h> 92 #include <sys/malloc.h> 93 #include <sys/sysctl.h> 94 #include <machine/md_var.h> 95 #include <sys/ctype.h> 96 #include <sys/syslog.h> 97 #include <sys/device.h> 98 #include <sys/msgport.h> 99 #include <sys/msgport2.h> 100 #include <sys/buf2.h> 101 102 static MALLOC_DEFINE(M_DISK, "disk", "disk data"); 103 104 static d_open_t diskopen; 105 static d_close_t diskclose; 106 static d_ioctl_t diskioctl; 107 static d_strategy_t diskstrategy; 108 static d_psize_t diskpsize; 109 static d_clone_t diskclone; 110 static d_dump_t diskdump; 111 112 static LIST_HEAD(, disk) disklist = LIST_HEAD_INITIALIZER(&disklist); 113 114 static struct dev_ops disk_ops = { 115 { "disk", 0, D_DISK }, 116 .d_open = diskopen, 117 .d_close = diskclose, 118 .d_read = physread, 119 .d_write = physwrite, 120 .d_ioctl = diskioctl, 121 .d_strategy = diskstrategy, 122 .d_dump = diskdump, 123 .d_psize = diskpsize, 124 .d_clone = diskclone 125 }; 126 127 /* 128 * Create a raw device for the dev_ops template (which is returned). Also 129 * create a slice and unit managed disk and overload the user visible 130 * device space with it. 131 * 132 * NOTE: The returned raw device is NOT a slice and unit managed device. 133 * It is an actual raw device representing the raw disk as specified by 134 * the passed dev_ops. The disk layer not only returns such a raw device, 135 * it also uses it internally when passing (modified) commands through. 136 */ 137 cdev_t 138 disk_create(int unit, struct disk *dp, struct dev_ops *raw_ops) 139 { 140 cdev_t rawdev; 141 struct dev_ops *dev_ops; 142 143 /* 144 * Create the raw backing device 145 */ 146 compile_dev_ops(raw_ops); 147 rawdev = make_dev(raw_ops, dkmakewholedisk(unit), 148 UID_ROOT, GID_OPERATOR, 0640, 149 "%s%d", raw_ops->head.name, unit); 150 151 bzero(dp, sizeof(*dp)); 152 153 /* 154 * We install a custom cdevsw rather then the passed cdevsw, 155 * and save our disk structure in d_data so we can get at it easily 156 * without any complex cloning code. 157 */ 158 dev_ops = dev_ops_add_override(rawdev, &disk_ops, 159 dkunitmask(), dkmakeunit(unit)); 160 dev_ops->head.data = dp; 161 162 dp->d_rawdev = rawdev; 163 dp->d_raw_ops = raw_ops; 164 dp->d_dev_ops = dev_ops; 165 dp->d_cdev = make_dev(dev_ops, 166 dkmakewholedisk(unit), 167 UID_ROOT, GID_OPERATOR, 0640, 168 "%s%d", dev_ops->head.name, unit); 169 170 LIST_INSERT_HEAD(&disklist, dp, d_list); 171 return (dp->d_rawdev); 172 } 173 174 /* 175 * Disk drivers must call this routine when media parameters are available 176 * or have changed. 177 */ 178 void 179 disk_setdiskinfo(struct disk *disk, struct disk_info *info) 180 { 181 bcopy(info, &disk->d_info, sizeof(disk->d_info)); 182 info = &disk->d_info; 183 184 KKASSERT(info->d_media_size == 0 || info->d_media_blksize == 0); 185 if (info->d_media_size == 0 && info->d_media_blocks) { 186 info->d_media_size = (u_int64_t)info->d_media_blocks * 187 info->d_media_blksize; 188 } else if (info->d_media_size && info->d_media_blocks == 0 && 189 info->d_media_blksize) { 190 info->d_media_blocks = info->d_media_size / 191 info->d_media_blksize; 192 } 193 194 /* 195 * The si_* fields for rawdev are not set until after the 196 * disk_create() call, so someone using the cooked version 197 * of the raw device (i.e. da0s0) will not get the right 198 * si_iosize_max unless we fix it up here. 199 */ 200 if (disk->d_cdev && disk->d_rawdev && 201 disk->d_cdev->si_iosize_max == 0) { 202 disk->d_cdev->si_iosize_max = disk->d_rawdev->si_iosize_max; 203 disk->d_cdev->si_bsize_phys = disk->d_rawdev->si_bsize_phys; 204 disk->d_cdev->si_bsize_best = disk->d_rawdev->si_bsize_best; 205 } 206 } 207 208 /* 209 * This routine is called when an adapter detaches. The higher level 210 * managed disk device is destroyed while the lower level raw device is 211 * released. 212 */ 213 void 214 disk_destroy(struct disk *disk) 215 { 216 u_int match; 217 218 if (disk->d_dev_ops) { 219 match = dkmakeunit(dkunit(disk->d_cdev)); 220 dev_ops_remove_override(disk->d_dev_ops, dkunitmask(), match); 221 LIST_REMOVE(disk, d_list); 222 } 223 if (disk->d_raw_ops) { 224 match = dkmakeunit(dkunit(disk->d_rawdev)); 225 destroy_all_devs(disk->d_raw_ops, dkunitmask(), match); 226 } 227 bzero(disk, sizeof(*disk)); 228 } 229 230 int 231 disk_dumpcheck(cdev_t dev, u_int64_t *count, u_int64_t *blkno, u_int *secsize) 232 { 233 struct partinfo pinfo; 234 int error; 235 236 bzero(&pinfo, sizeof(pinfo)); 237 error = dev_dioctl(dev, DIOCGPART, (void *)&pinfo, 0, proc0.p_ucred); 238 if (error) 239 return (error); 240 if (pinfo.media_blksize == 0) 241 return (ENXIO); 242 *count = (u_int64_t)Maxmem * PAGE_SIZE / pinfo.media_blksize; 243 if (dumplo64 < pinfo.reserved_blocks || 244 dumplo64 + *count > pinfo.media_blocks) { 245 return (ENOSPC); 246 } 247 *blkno = dumplo64 + pinfo.media_offset / pinfo.media_blksize; 248 *secsize = pinfo.media_blksize; 249 return (0); 250 } 251 252 void 253 disk_invalidate (struct disk *disk) 254 { 255 if (disk->d_slice) 256 dsgone(&disk->d_slice); 257 } 258 259 struct disk * 260 disk_enumerate(struct disk *disk) 261 { 262 if (!disk) 263 return (LIST_FIRST(&disklist)); 264 else 265 return (LIST_NEXT(disk, d_list)); 266 } 267 268 static 269 int 270 sysctl_disks(SYSCTL_HANDLER_ARGS) 271 { 272 struct disk *disk; 273 int error, first; 274 275 disk = NULL; 276 first = 1; 277 278 while ((disk = disk_enumerate(disk))) { 279 if (!first) { 280 error = SYSCTL_OUT(req, " ", 1); 281 if (error) 282 return error; 283 } else { 284 first = 0; 285 } 286 error = SYSCTL_OUT(req, disk->d_rawdev->si_name, 287 strlen(disk->d_rawdev->si_name)); 288 if (error) 289 return error; 290 } 291 error = SYSCTL_OUT(req, "", 1); 292 return error; 293 } 294 295 SYSCTL_PROC(_kern, OID_AUTO, disks, CTLTYPE_STRING | CTLFLAG_RD, NULL, 0, 296 sysctl_disks, "A", "names of available disks"); 297 298 /* 299 * Open a disk device or partition. 300 */ 301 static 302 int 303 diskopen(struct dev_open_args *ap) 304 { 305 cdev_t dev = ap->a_head.a_dev; 306 struct disk *dp; 307 int error; 308 309 /* 310 * dp can't be NULL here XXX. 311 */ 312 dp = dev->si_disk; 313 if (dp == NULL) 314 return (ENXIO); 315 error = 0; 316 317 /* 318 * Deal with open races 319 */ 320 while (dp->d_flags & DISKFLAG_LOCK) { 321 dp->d_flags |= DISKFLAG_WANTED; 322 error = tsleep(dp, PCATCH, "diskopen", hz); 323 if (error) 324 return (error); 325 } 326 dp->d_flags |= DISKFLAG_LOCK; 327 328 /* 329 * Open the underlying raw device. 330 */ 331 if (!dsisopen(dp->d_slice)) { 332 #if 0 333 if (!pdev->si_iosize_max) 334 pdev->si_iosize_max = dev->si_iosize_max; 335 #endif 336 error = dev_dopen(dp->d_rawdev, ap->a_oflags, 337 ap->a_devtype, ap->a_cred); 338 } 339 340 /* 341 * Inherit properties from the underlying device now that it is 342 * open. 343 */ 344 dev_dclone(dev); 345 346 if (error) 347 goto out; 348 349 error = dsopen(dev, ap->a_devtype, dp->d_info.d_dsflags, 350 &dp->d_slice, &dp->d_info); 351 352 if (!dsisopen(dp->d_slice)) 353 dev_dclose(dp->d_rawdev, ap->a_oflags, ap->a_devtype); 354 out: 355 dp->d_flags &= ~DISKFLAG_LOCK; 356 if (dp->d_flags & DISKFLAG_WANTED) { 357 dp->d_flags &= ~DISKFLAG_WANTED; 358 wakeup(dp); 359 } 360 361 return(error); 362 } 363 364 /* 365 * Close a disk device or partition 366 */ 367 static 368 int 369 diskclose(struct dev_close_args *ap) 370 { 371 cdev_t dev = ap->a_head.a_dev; 372 struct disk *dp; 373 int error; 374 375 error = 0; 376 dp = dev->si_disk; 377 378 dsclose(dev, ap->a_devtype, dp->d_slice); 379 if (!dsisopen(dp->d_slice)) 380 error = dev_dclose(dp->d_rawdev, ap->a_fflag, ap->a_devtype); 381 return (error); 382 } 383 384 /* 385 * First execute the ioctl on the disk device, and if it isn't supported 386 * try running it on the backing device. 387 */ 388 static 389 int 390 diskioctl(struct dev_ioctl_args *ap) 391 { 392 cdev_t dev = ap->a_head.a_dev; 393 struct disk *dp; 394 int error; 395 396 dp = dev->si_disk; 397 if (dp == NULL) 398 return (ENXIO); 399 error = dsioctl(dev, ap->a_cmd, ap->a_data, ap->a_fflag, 400 &dp->d_slice, &dp->d_info); 401 if (error == ENOIOCTL) { 402 error = dev_dioctl(dp->d_rawdev, ap->a_cmd, ap->a_data, 403 ap->a_fflag, ap->a_cred); 404 } 405 return (error); 406 } 407 408 /* 409 * Execute strategy routine 410 */ 411 static 412 int 413 diskstrategy(struct dev_strategy_args *ap) 414 { 415 cdev_t dev = ap->a_head.a_dev; 416 struct bio *bio = ap->a_bio; 417 struct bio *nbio; 418 struct disk *dp; 419 420 dp = dev->si_disk; 421 422 if (dp == NULL) { 423 bio->bio_buf->b_error = ENXIO; 424 bio->bio_buf->b_flags |= B_ERROR; 425 biodone(bio); 426 return(0); 427 } 428 KKASSERT(dev->si_disk == dp); 429 430 /* 431 * The dscheck() function will also transform the slice relative 432 * block number i.e. bio->bio_offset into a block number that can be 433 * passed directly to the underlying raw device. If dscheck() 434 * returns NULL it will have handled the bio for us (e.g. EOF 435 * or error due to being beyond the device size). 436 */ 437 if ((nbio = dscheck(dev, bio, dp->d_slice)) != NULL) 438 dev_dstrategy(dp->d_rawdev, nbio); 439 else 440 biodone(bio); 441 return(0); 442 } 443 444 /* 445 * Return the partition size in ?blocks? 446 */ 447 static 448 int 449 diskpsize(struct dev_psize_args *ap) 450 { 451 cdev_t dev = ap->a_head.a_dev; 452 struct disk *dp; 453 454 dp = dev->si_disk; 455 if (dp == NULL) 456 return(ENODEV); 457 ap->a_result = dssize(dev, &dp->d_slice); 458 return(0); 459 } 460 461 /* 462 * When new device entries are instantiated, make sure they inherit our 463 * si_disk structure and block and iosize limits from the raw device. 464 * 465 * This routine is always called synchronously in the context of the 466 * client. 467 * 468 * XXX The various io and block size constraints are not always initialized 469 * properly by devices. 470 */ 471 static 472 int 473 diskclone(struct dev_clone_args *ap) 474 { 475 cdev_t dev = ap->a_head.a_dev; 476 struct disk *dp; 477 478 dp = dev->si_ops->head.data; 479 KKASSERT(dp != NULL); 480 dev->si_disk = dp; 481 dev->si_iosize_max = dp->d_rawdev->si_iosize_max; 482 dev->si_bsize_phys = dp->d_rawdev->si_bsize_phys; 483 dev->si_bsize_best = dp->d_rawdev->si_bsize_best; 484 return(0); 485 } 486 487 int 488 diskdump(struct dev_dump_args *ap) 489 { 490 cdev_t dev = ap->a_head.a_dev; 491 struct disk *dp = dev->si_ops->head.data; 492 int error; 493 494 error = disk_dumpcheck(dev, &ap->a_count, &ap->a_blkno, &ap->a_secsize); 495 if (error == 0) { 496 ap->a_head.a_dev = dp->d_rawdev; 497 error = dev_doperate(&ap->a_head); 498 } 499 500 return(error); 501 } 502 503 504 SYSCTL_INT(_debug_sizeof, OID_AUTO, diskslices, CTLFLAG_RD, 505 0, sizeof(struct diskslices), "sizeof(struct diskslices)"); 506 507 SYSCTL_INT(_debug_sizeof, OID_AUTO, disk, CTLFLAG_RD, 508 0, sizeof(struct disk), "sizeof(struct disk)"); 509 510 511 /* 512 * Seek sort for disks. 513 * 514 * The bio_queue keep two queues, sorted in ascending block order. The first 515 * queue holds those requests which are positioned after the current block 516 * (in the first request); the second, which starts at queue->switch_point, 517 * holds requests which came in after their block number was passed. Thus 518 * we implement a one way scan, retracting after reaching the end of the drive 519 * to the first request on the second queue, at which time it becomes the 520 * first queue. 521 * 522 * A one-way scan is natural because of the way UNIX read-ahead blocks are 523 * allocated. 524 */ 525 void 526 bioqdisksort(struct bio_queue_head *bioq, struct bio *bio) 527 { 528 struct bio *bq; 529 struct bio *bn; 530 struct bio *be; 531 532 be = TAILQ_LAST(&bioq->queue, bio_queue); 533 /* 534 * If the queue is empty or we are an 535 * ordered transaction, then it's easy. 536 */ 537 if ((bq = bioq_first(bioq)) == NULL || 538 (bio->bio_buf->b_flags & B_ORDERED) != 0) { 539 bioq_insert_tail(bioq, bio); 540 return; 541 } else if (bioq->insert_point != NULL) { 542 543 /* 544 * A certain portion of the list is 545 * "locked" to preserve ordering, so 546 * we can only insert after the insert 547 * point. 548 */ 549 bq = bioq->insert_point; 550 } else { 551 552 /* 553 * If we lie before the last removed (currently active) 554 * request, and are not inserting ourselves into the 555 * "locked" portion of the list, then we must add ourselves 556 * to the second request list. 557 */ 558 if (bio->bio_offset < bioq->last_offset) { 559 bq = bioq->switch_point; 560 /* 561 * If we are starting a new secondary list, 562 * then it's easy. 563 */ 564 if (bq == NULL) { 565 bioq->switch_point = bio; 566 bioq_insert_tail(bioq, bio); 567 return; 568 } 569 /* 570 * If we lie ahead of the current switch point, 571 * insert us before the switch point and move 572 * the switch point. 573 */ 574 if (bio->bio_offset < bq->bio_offset) { 575 bioq->switch_point = bio; 576 TAILQ_INSERT_BEFORE(bq, bio, bio_act); 577 return; 578 } 579 } else { 580 if (bioq->switch_point != NULL) 581 be = TAILQ_PREV(bioq->switch_point, 582 bio_queue, bio_act); 583 /* 584 * If we lie between last_offset and bq, 585 * insert before bq. 586 */ 587 if (bio->bio_offset < bq->bio_offset) { 588 TAILQ_INSERT_BEFORE(bq, bio, bio_act); 589 return; 590 } 591 } 592 } 593 594 /* 595 * Request is at/after our current position in the list. 596 * Optimize for sequential I/O by seeing if we go at the tail. 597 */ 598 if (bio->bio_offset > be->bio_offset) { 599 TAILQ_INSERT_AFTER(&bioq->queue, be, bio, bio_act); 600 return; 601 } 602 603 /* Otherwise, insertion sort */ 604 while ((bn = TAILQ_NEXT(bq, bio_act)) != NULL) { 605 606 /* 607 * We want to go after the current request if it is the end 608 * of the first request list, or if the next request is a 609 * larger cylinder than our request. 610 */ 611 if (bn == bioq->switch_point 612 || bio->bio_offset < bn->bio_offset) 613 break; 614 bq = bn; 615 } 616 TAILQ_INSERT_AFTER(&bioq->queue, bq, bio, bio_act); 617 } 618 619 /* 620 * Disk error is the preface to plaintive error messages 621 * about failing disk transfers. It prints messages of the form 622 623 hp0g: hard error reading fsbn 12345 of 12344-12347 (hp0 bn %d cn %d tn %d sn %d) 624 625 * if the offset of the error in the transfer and a disk label 626 * are both available. blkdone should be -1 if the position of the error 627 * is unknown; the disklabel pointer may be null from drivers that have not 628 * been converted to use them. The message is printed with kprintf 629 * if pri is LOG_PRINTF, otherwise it uses log at the specified priority. 630 * The message should be completed (with at least a newline) with kprintf 631 * or log(-1, ...), respectively. There is no trailing space. 632 */ 633 void 634 diskerr(struct bio *bio, cdev_t dev, const char *what, int pri, int donecnt) 635 { 636 struct buf *bp = bio->bio_buf; 637 int unit = dkunit(dev); 638 int slice = dkslice(dev); 639 int part = dkpart(dev); 640 char partname[2]; 641 char *sname; 642 const char *term; 643 644 switch(bp->b_cmd) { 645 case BUF_CMD_READ: 646 term = "read"; 647 break; 648 case BUF_CMD_WRITE: 649 term = "write"; 650 break; 651 default: 652 term = "access"; 653 break; 654 } 655 sname = dsname(dev, unit, slice, part, partname); 656 kprintf("%s%s: %s %sing ", sname, partname, what, term); 657 kprintf("offset %012llx for %d", 658 (long long)bio->bio_offset, 659 bp->b_bcount); 660 if (donecnt) 661 kprintf(" (%d bytes completed)", donecnt); 662 } 663 664 /* 665 * Locate a disk device 666 */ 667 cdev_t 668 disk_locate(const char *devname) 669 { 670 struct disk *dp; 671 cdev_t dev; 672 char *ptr; 673 int i; 674 int prefix; 675 int slice; 676 int part; 677 678 /* 679 * Device and unit 680 */ 681 for (i = 0; devname[i]; ++i) { 682 if (devname[i] >= '0' && devname[i] <= '9') 683 break; 684 } 685 while (devname[i] >= '0' && devname[i] <= '9') 686 ++i; 687 prefix = i; 688 689 /* 690 * Slice and partition. s1 starts at slice #2. s0 is slice #0. 691 * slice #1 is the WHOLE_DISK_SLICE. 692 */ 693 if (devname[i] == 's') { 694 slice = strtol(devname + i + 1, &ptr, 10); 695 i = (const char *)ptr - devname; 696 if (slice > 0) 697 ++slice; 698 } else { 699 slice = WHOLE_DISK_SLICE; 700 } 701 if (devname[i] >= 'a' && devname[i] <= 'z') { 702 part = devname[i] - 'a'; 703 } else { 704 part = WHOLE_SLICE_PART; 705 } 706 707 /* 708 * Find the device 709 */ 710 LIST_FOREACH(dp, &disklist, d_list) { 711 dev = dp->d_cdev; 712 if (strlen(dev->si_name) == prefix && 713 strncmp(devname, dev->si_name, prefix) == 0 714 ) { 715 return(dkmodpart(dkmodslice(dev, slice), part)); 716 } 717 } 718 return(NULL); 719 } 720 721