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subr_disk.c revision 1.116.2.1
      1 /*	$NetBSD: subr_disk.c,v 1.116.2.1 2017/03/20 06:57:47 pgoyette Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996, 1997, 1999, 2000, 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9  * NASA Ames Research Center.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  *
     20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30  * POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 /*
     34  * Copyright (c) 1982, 1986, 1988, 1993
     35  *	The Regents of the University of California.  All rights reserved.
     36  * (c) UNIX System Laboratories, Inc.
     37  * All or some portions of this file are derived from material licensed
     38  * to the University of California by American Telephone and Telegraph
     39  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
     40  * the permission of UNIX System Laboratories, Inc.
     41  *
     42  * Redistribution and use in source and binary forms, with or without
     43  * modification, are permitted provided that the following conditions
     44  * are met:
     45  * 1. Redistributions of source code must retain the above copyright
     46  *    notice, this list of conditions and the following disclaimer.
     47  * 2. Redistributions in binary form must reproduce the above copyright
     48  *    notice, this list of conditions and the following disclaimer in the
     49  *    documentation and/or other materials provided with the distribution.
     50  * 3. 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  *	@(#)ufs_disksubr.c	8.5 (Berkeley) 1/21/94
     67  */
     68 
     69 #include <sys/cdefs.h>
     70 __KERNEL_RCSID(0, "$NetBSD: subr_disk.c,v 1.116.2.1 2017/03/20 06:57:47 pgoyette Exp $");
     71 
     72 #include <sys/param.h>
     73 #include <sys/kernel.h>
     74 #include <sys/kmem.h>
     75 #include <sys/buf.h>
     76 #include <sys/fcntl.h>
     77 #include <sys/syslog.h>
     78 #include <sys/disklabel.h>
     79 #include <sys/disk.h>
     80 #include <sys/sysctl.h>
     81 #include <lib/libkern/libkern.h>
     82 
     83 /*
     84  * Compute checksum for disk label.
     85  */
     86 u_int
     87 dkcksum(struct disklabel *lp)
     88 {
     89 
     90 	return dkcksum_sized(lp, lp->d_npartitions);
     91 }
     92 
     93 u_int
     94 dkcksum_sized(struct disklabel *lp, size_t npartitions)
     95 {
     96 	uint16_t *start, *end;
     97 	uint16_t sum = 0;
     98 
     99 	start = (uint16_t *)lp;
    100 	end = (uint16_t *)&lp->d_partitions[npartitions];
    101 	while (start < end)
    102 		sum ^= *start++;
    103 	return sum;
    104 }
    105 
    106 /*
    107  * Disk error is the preface to plaintive error messages
    108  * about failing disk transfers.  It prints messages of the form
    109 
    110 hp0g: hard error reading fsbn 12345 of 12344-12347 (hp0 bn %d cn %d tn %d sn %d)
    111 
    112  * if the offset of the error in the transfer and a disk label
    113  * are both available.  blkdone should be -1 if the position of the error
    114  * is unknown; the disklabel pointer may be null from drivers that have not
    115  * been converted to use them.  The message is printed with printf
    116  * if pri is LOG_PRINTF, otherwise it uses log at the specified priority.
    117  * The message should be completed (with at least a newline) with printf
    118  * or addlog, respectively.  There is no trailing space.
    119  */
    120 #ifndef PRIdaddr
    121 #define PRIdaddr PRId64
    122 #endif
    123 void
    124 diskerr(const struct buf *bp, const char *dname, const char *what, int pri,
    125     int blkdone, const struct disklabel *lp)
    126 {
    127 	int unit = DISKUNIT(bp->b_dev), part = DISKPART(bp->b_dev);
    128 	void (*pr)(const char *, ...) __printflike(1, 2);
    129 	char partname = 'a' + part;
    130 	daddr_t sn;
    131 
    132 	if (/*CONSTCOND*/0)
    133 		/* Compiler will error this is the format is wrong... */
    134 		printf("%" PRIdaddr, bp->b_blkno);
    135 
    136 	if (pri != LOG_PRINTF) {
    137 		static const char fmt[] = "";
    138 		log(pri, fmt);
    139 		pr = addlog;
    140 	} else
    141 		pr = printf;
    142 	(*pr)("%s%d%c: %s %sing fsbn ", dname, unit, partname, what,
    143 	    bp->b_flags & B_READ ? "read" : "writ");
    144 	sn = bp->b_blkno;
    145 	if (bp->b_bcount <= DEV_BSIZE)
    146 		(*pr)("%" PRIdaddr, sn);
    147 	else {
    148 		if (blkdone >= 0) {
    149 			sn += blkdone;
    150 			(*pr)("%" PRIdaddr " of ", sn);
    151 		}
    152 		(*pr)("%" PRIdaddr "-%" PRIdaddr "", bp->b_blkno,
    153 		    bp->b_blkno + (bp->b_bcount - 1) / DEV_BSIZE);
    154 	}
    155 	if (lp && (blkdone >= 0 || bp->b_bcount <= lp->d_secsize)) {
    156 		sn += lp->d_partitions[part].p_offset;
    157 		(*pr)(" (%s%d bn %" PRIdaddr "; cn %" PRIdaddr "",
    158 		    dname, unit, sn, sn / lp->d_secpercyl);
    159 		sn %= lp->d_secpercyl;
    160 		(*pr)(" tn %" PRIdaddr " sn %" PRIdaddr ")",
    161 		    sn / lp->d_nsectors, sn % lp->d_nsectors);
    162 	}
    163 }
    164 
    165 /*
    166  * Searches the iostatlist for the disk corresponding to the
    167  * name provided.
    168  */
    169 struct disk *
    170 disk_find(const char *name)
    171 {
    172 	struct io_stats *stat;
    173 
    174 	stat = iostat_find(name);
    175 
    176 	if ((stat != NULL) && (stat->io_type == IOSTAT_DISK))
    177 		return stat->io_parent;
    178 
    179 	return (NULL);
    180 }
    181 
    182 void
    183 disk_init(struct disk *diskp, const char *name, const struct dkdriver *driver)
    184 {
    185 	u_int blocksize = DEV_BSIZE;
    186 
    187 	/*
    188 	 * Initialize the wedge-related locks and other fields.
    189 	 */
    190 	mutex_init(&diskp->dk_rawlock, MUTEX_DEFAULT, IPL_NONE);
    191 	mutex_init(&diskp->dk_openlock, MUTEX_DEFAULT, IPL_NONE);
    192 	LIST_INIT(&diskp->dk_wedges);
    193 	diskp->dk_nwedges = 0;
    194 	diskp->dk_labelsector = LABELSECTOR;
    195 	diskp->dk_blkshift = DK_BSIZE2BLKSHIFT(blocksize);
    196 	diskp->dk_byteshift = DK_BSIZE2BYTESHIFT(blocksize);
    197 	diskp->dk_name = name;
    198 	diskp->dk_driver = driver;
    199 }
    200 
    201 /*
    202  * Attach a disk.
    203  */
    204 void
    205 disk_attach(struct disk *diskp)
    206 {
    207 
    208 	/*
    209 	 * Allocate and initialize the disklabel structures.
    210 	 */
    211 	diskp->dk_label = kmem_zalloc(sizeof(struct disklabel), KM_SLEEP);
    212 	diskp->dk_cpulabel = kmem_zalloc(sizeof(struct cpu_disklabel),
    213 	    KM_SLEEP);
    214 	if ((diskp->dk_label == NULL) || (diskp->dk_cpulabel == NULL))
    215 		panic("disk_attach: can't allocate storage for disklabel");
    216 
    217 	/*
    218 	 * Set up the stats collection.
    219 	 */
    220 	diskp->dk_stats = iostat_alloc(IOSTAT_DISK, diskp, diskp->dk_name);
    221 }
    222 
    223 int
    224 disk_begindetach(struct disk *dk, int (*lastclose)(device_t),
    225     device_t self, int flags)
    226 {
    227 	int rc;
    228 
    229 	rc = 0;
    230 	mutex_enter(&dk->dk_openlock);
    231 	if (dk->dk_openmask == 0)
    232 		;	/* nothing to do */
    233 	else if ((flags & DETACH_FORCE) == 0)
    234 		rc = EBUSY;
    235 	else if (lastclose != NULL)
    236 		rc = (*lastclose)(self);
    237 	mutex_exit(&dk->dk_openlock);
    238 
    239 	return rc;
    240 }
    241 
    242 /*
    243  * Detach a disk.
    244  */
    245 void
    246 disk_detach(struct disk *diskp)
    247 {
    248 
    249 	/*
    250 	 * Remove from the drivelist.
    251 	 */
    252 	iostat_free(diskp->dk_stats);
    253 
    254 	/*
    255 	 * Release the disk-info dictionary.
    256 	 */
    257 	if (diskp->dk_info) {
    258 		prop_object_release(diskp->dk_info);
    259 		diskp->dk_info = NULL;
    260 	}
    261 
    262 	/*
    263 	 * Free the space used by the disklabel structures.
    264 	 */
    265 	kmem_free(diskp->dk_label, sizeof(*diskp->dk_label));
    266 	kmem_free(diskp->dk_cpulabel, sizeof(*diskp->dk_cpulabel));
    267 }
    268 
    269 void
    270 disk_destroy(struct disk *diskp)
    271 {
    272 
    273 	mutex_destroy(&diskp->dk_openlock);
    274 	mutex_destroy(&diskp->dk_rawlock);
    275 }
    276 
    277 /*
    278  * Mark the disk as having work queued for metrics collection.
    279  */
    280 void
    281 disk_wait(struct disk *diskp)
    282 {
    283 
    284 	iostat_wait(diskp->dk_stats);
    285 }
    286 
    287 /*
    288  * Mark the disk as busy for metrics collection.
    289  */
    290 void
    291 disk_busy(struct disk *diskp)
    292 {
    293 
    294 	iostat_busy(diskp->dk_stats);
    295 }
    296 
    297 /*
    298  * Finished disk operations, gather metrics.
    299  */
    300 void
    301 disk_unbusy(struct disk *diskp, long bcount, int read)
    302 {
    303 
    304 	iostat_unbusy(diskp->dk_stats, bcount, read);
    305 }
    306 
    307 /*
    308  * Return true if disk has an I/O operation in flight.
    309  */
    310 bool
    311 disk_isbusy(struct disk *diskp)
    312 {
    313 
    314 	return iostat_isbusy(diskp->dk_stats);
    315 }
    316 
    317 /*
    318  * Bounds checking against the media size, used for the raw partition.
    319  * secsize, mediasize and b_blkno must all be the same units.
    320  * Possibly this has to be DEV_BSIZE (512).
    321  */
    322 int
    323 bounds_check_with_mediasize(struct buf *bp, int secsize, uint64_t mediasize)
    324 {
    325 	int64_t sz;
    326 
    327 	if (bp->b_blkno < 0) {
    328 		/* Reject negative offsets immediately. */
    329 		bp->b_error = EINVAL;
    330 		return 0;
    331 	}
    332 
    333 	sz = howmany((int64_t)bp->b_bcount, secsize);
    334 
    335 	/*
    336 	 * bp->b_bcount is a 32-bit value, and we rejected a negative
    337 	 * bp->b_blkno already, so "bp->b_blkno + sz" cannot overflow.
    338 	 */
    339 
    340 	if (bp->b_blkno + sz > mediasize) {
    341 		sz = mediasize - bp->b_blkno;
    342 		if (sz == 0) {
    343 			/* If exactly at end of disk, return EOF. */
    344 			bp->b_resid = bp->b_bcount;
    345 			return 0;
    346 		}
    347 		if (sz < 0) {
    348 			/* If past end of disk, return EINVAL. */
    349 			bp->b_error = EINVAL;
    350 			return 0;
    351 		}
    352 		/* Otherwise, truncate request. */
    353 		bp->b_bcount = sz * secsize;
    354 	}
    355 
    356 	return 1;
    357 }
    358 
    359 /*
    360  * Determine the size of the transfer, and make sure it is
    361  * within the boundaries of the partition. Adjust transfer
    362  * if needed, and signal errors or early completion.
    363  */
    364 int
    365 bounds_check_with_label(struct disk *dk, struct buf *bp, int wlabel)
    366 {
    367 	struct disklabel *lp = dk->dk_label;
    368 	struct partition *p = lp->d_partitions + DISKPART(bp->b_dev);
    369 	uint64_t p_size, p_offset, labelsector;
    370 	int64_t sz;
    371 
    372 	if (bp->b_blkno < 0) {
    373 		/* Reject negative offsets immediately. */
    374 		bp->b_error = EINVAL;
    375 		return -1;
    376 	}
    377 
    378 	/* Protect against division by zero. XXX: Should never happen?!?! */
    379 	if (lp->d_secpercyl == 0) {
    380 		bp->b_error = EINVAL;
    381 		return -1;
    382 	}
    383 
    384 	p_size = (uint64_t)p->p_size << dk->dk_blkshift;
    385 	p_offset = (uint64_t)p->p_offset << dk->dk_blkshift;
    386 #if RAW_PART == 3
    387 	labelsector = lp->d_partitions[2].p_offset;
    388 #else
    389 	labelsector = lp->d_partitions[RAW_PART].p_offset;
    390 #endif
    391 	labelsector = (labelsector + dk->dk_labelsector) << dk->dk_blkshift;
    392 
    393 	sz = howmany((int64_t)bp->b_bcount, DEV_BSIZE);
    394 
    395 	/*
    396 	 * bp->b_bcount is a 32-bit value, and we rejected a negative
    397 	 * bp->b_blkno already, so "bp->b_blkno + sz" cannot overflow.
    398 	 */
    399 
    400 	if (bp->b_blkno + sz > p_size) {
    401 		sz = p_size - bp->b_blkno;
    402 		if (sz == 0) {
    403 			/* If exactly at end of disk, return EOF. */
    404 			bp->b_resid = bp->b_bcount;
    405 			return 0;
    406 		}
    407 		if (sz < 0) {
    408 			/* If past end of disk, return EINVAL. */
    409 			bp->b_error = EINVAL;
    410 			return -1;
    411 		}
    412 		/* Otherwise, truncate request. */
    413 		bp->b_bcount = sz << DEV_BSHIFT;
    414 	}
    415 
    416 	/* Overwriting disk label? */
    417 	if (bp->b_blkno + p_offset <= labelsector &&
    418 	    bp->b_blkno + p_offset + sz > labelsector &&
    419 	    (bp->b_flags & B_READ) == 0 && !wlabel) {
    420 		bp->b_error = EROFS;
    421 		return -1;
    422 	}
    423 
    424 	/* calculate cylinder for disksort to order transfers with */
    425 	bp->b_cylinder = (bp->b_blkno + p->p_offset) /
    426 	    (lp->d_secsize / DEV_BSIZE) / lp->d_secpercyl;
    427 	return 1;
    428 }
    429 
    430 int
    431 disk_read_sectors(void (*strat)(struct buf *), const struct disklabel *lp,
    432     struct buf *bp, unsigned int sector, int count)
    433 {
    434 	bp->b_blkno = btodb((off_t)sector * lp->d_secsize);
    435 	bp->b_bcount = count * lp->d_secsize;
    436 	bp->b_flags = (bp->b_flags & ~B_WRITE) | B_READ;
    437 	bp->b_oflags &= ~BO_DONE;
    438 	bp->b_cylinder = sector / lp->d_secpercyl;
    439 	(*strat)(bp);
    440 	return biowait(bp);
    441 }
    442 
    443 const char *
    444 convertdisklabel(struct disklabel *lp, void (*strat)(struct buf *),
    445     struct buf *bp, uint32_t secperunit)
    446 {
    447 	struct partition rp, *altp, *p;
    448 	int geom_ok;
    449 	const char *str;
    450 
    451 	memset(&rp, 0, sizeof(rp));
    452 	rp.p_size = secperunit;
    453 	rp.p_fstype = FS_UNUSED;
    454 
    455 	/* If we can seek to d_secperunit - 1, believe the disk geometry. */
    456 	if (secperunit != 0 &&
    457 	    disk_read_sectors(strat, lp, bp, secperunit - 1, 1) == 0)
    458 		geom_ok = 1;
    459 	else
    460 		geom_ok = 0;
    461 
    462 #if 0
    463 	printf("%s: secperunit (%" PRIu32 ") %s\n", __func__,
    464 	    secperunit, geom_ok ? "ok" : "not ok");
    465 #endif
    466 
    467 	p = &lp->d_partitions[RAW_PART];
    468 	if (RAW_PART == 'c' - 'a')
    469 		altp = &lp->d_partitions['d' - 'a'];
    470 	else
    471 		altp = &lp->d_partitions['c' - 'a'];
    472 
    473 	if (lp->d_npartitions > RAW_PART && p->p_offset == 0 && p->p_size != 0)
    474 		return NULL;	/* already a raw partition */
    475 	else if (lp->d_npartitions > MAX('c', 'd') - 'a' &&
    476 		 altp->p_offset == 0 && altp->p_size != 0) {
    477 		/* alternate partition ('c' or 'd') is suitable for raw slot,
    478 		 * swap with 'd' or 'c'.
    479 		 */
    480 		rp = *p;
    481 		*p = *altp;
    482 		*altp = rp;
    483 		return NULL;
    484 	} else if (lp->d_npartitions <= RAW_PART &&
    485 	           lp->d_npartitions > 'c' - 'a') {
    486 		/* No raw partition is present, but the alternate is present.
    487 		 * Copy alternate to raw partition.
    488 		 */
    489 		lp->d_npartitions = RAW_PART + 1;
    490 		*p = *altp;
    491 		return NULL;
    492 	} else if (!geom_ok)
    493 		str = "no raw partition and disk reports bad geometry";
    494 	else if (lp->d_npartitions <= RAW_PART) {
    495 		memset(&lp->d_partitions[lp->d_npartitions], 0,
    496 		    sizeof(struct partition) * (RAW_PART - lp->d_npartitions));
    497 		*p = rp;
    498 		lp->d_npartitions = RAW_PART + 1;
    499 		return NULL;
    500 	} else if (lp->d_npartitions < MAXPARTITIONS) {
    501 		memmove(p + 1, p,
    502 		    sizeof(struct partition) * (lp->d_npartitions - RAW_PART));
    503 		*p = rp;
    504 		lp->d_npartitions++;
    505 		return NULL;
    506 	} else
    507 		str = "no raw partition and partition table is full";
    508 #ifdef DIAGNOSTIC
    509 	printf("Bad partition: %s\n", str);
    510 	printf("type = %u, subtype = %u, typename = %s\n",
    511 	    lp->d_type, lp->d_subtype, lp->d_typename);
    512 	printf("secsize = %u, nsectors = %u, ntracks = %u\n",
    513 	    lp->d_secsize, lp->d_nsectors, lp->d_ntracks);
    514 	printf("ncylinders = %u, secpercyl = %u, secperunit = %u\n",
    515 	    lp->d_ncylinders, lp->d_secpercyl, lp->d_secperunit);
    516 	printf("npartitions = %u\n", lp->d_npartitions);
    517 
    518 	for (size_t i = 0; i < MIN(lp->d_npartitions, MAXPARTITIONS); i++) {
    519 		p = &lp->d_partitions[i];
    520 		printf("\t%c: offset = %u size = %u fstype = %u\n",
    521 		    (char)(i + 'a'), p->p_offset, p->p_size, p->p_fstype);
    522 	}
    523 #endif
    524 	return str;
    525 }
    526 
    527 /*
    528  * disk_ioctl --
    529  *	Generic disk ioctl handling.
    530  */
    531 int
    532 disk_ioctl(struct disk *dk, dev_t dev, u_long cmd, void *data, int flag,
    533     struct lwp *l)
    534 {
    535 	struct dkwedge_info *dkw;
    536 	struct partinfo *pi;
    537 	struct partition *dp;
    538 #ifdef __HAVE_OLD_DISKLABEL
    539 	struct disklabel newlabel;
    540 #endif
    541 
    542 	switch (cmd) {
    543 	case DIOCGDISKINFO:
    544 		if (dk->dk_info == NULL)
    545 			return ENOTSUP;
    546 		return prop_dictionary_copyout_ioctl(data, cmd, dk->dk_info);
    547 
    548 	case DIOCGSECTORSIZE:
    549 		*(u_int *)data = dk->dk_geom.dg_secsize;
    550 		return 0;
    551 
    552 	case DIOCGMEDIASIZE:
    553 		*(off_t *)data = (off_t)dk->dk_geom.dg_secsize *
    554 		    dk->dk_geom.dg_secperunit;
    555 		return 0;
    556 	default:
    557 		break;
    558 	}
    559 
    560 	if (dev == NODEV)
    561 		return EPASSTHROUGH;
    562 
    563 	/* The following should be moved to dk_ioctl */
    564 	switch (cmd) {
    565 	case DIOCGDINFO:
    566 		if (dk->dk_label == NULL)
    567 			return EBUSY;
    568 		memcpy(data, dk->dk_label, sizeof (*dk->dk_label));
    569 		return 0;
    570 
    571 #ifdef __HAVE_OLD_DISKLABEL
    572 	case ODIOCGDINFO:
    573 		if (dk->dk_label == NULL)
    574 			return EBUSY;
    575 		memcpy(&newlabel, dk->dk_label, sizeof(newlabel));
    576 		if (newlabel.d_npartitions > OLDMAXPARTITIONS)
    577 			return ENOTTY;
    578 		memcpy(data, &newlabel, sizeof(struct olddisklabel));
    579 		return 0;
    580 #endif
    581 
    582 	case DIOCGPARTINFO:
    583 		pi = data;
    584 		memset(pi, 0, sizeof(*pi));
    585 		pi->pi_secsize = dk->dk_geom.dg_secsize;
    586 		pi->pi_bsize = MAX(BLKDEV_IOSIZE, pi->pi_secsize);
    587 
    588 		if (DISKPART(dev) == RAW_PART) {
    589 			pi->pi_size = dk->dk_geom.dg_secperunit;
    590 			return 0;
    591 		}
    592 
    593 		if (dk->dk_label == NULL)
    594 			return EBUSY;
    595 
    596 		dp = &dk->dk_label->d_partitions[DISKPART(dev)];
    597 		pi->pi_offset = dp->p_offset;
    598 		pi->pi_size = dp->p_size;
    599 
    600 		pi->pi_fstype = dp->p_fstype;
    601 		pi->pi_frag = dp->p_frag;
    602 		pi->pi_fsize = dp->p_fsize;
    603 		pi->pi_cpg = dp->p_cpg;
    604 
    605 		/*
    606 		 * dholland 20130616: XXX this logic should not be
    607 		 * here. It is here because the old buffer cache
    608 		 * demands that all accesses to the same blocks need
    609 		 * to be the same size; but it only works for FFS and
    610 		 * nowadays I think it'll fail silently if the size
    611 		 * info in the disklabel is wrong. (Or missing.) The
    612 		 * buffer cache needs to be smarter; or failing that
    613 		 * we need a reliable way here to get the right block
    614 		 * size; or a reliable way to guarantee that (a) the
    615 		 * fs is not mounted when we get here and (b) any
    616 		 * buffers generated here will get purged when the fs
    617 		 * does get mounted.
    618 		 */
    619 		if (dp->p_fstype == FS_BSDFFS &&
    620 		    dp->p_frag != 0 && dp->p_fsize != 0)
    621 			pi->pi_bsize = dp->p_frag * dp->p_fsize;
    622 		return 0;
    623 
    624 	case DIOCAWEDGE:
    625 		if ((flag & FWRITE) == 0)
    626 			return EBADF;
    627 
    628 		dkw = data;
    629 		strlcpy(dkw->dkw_parent, dk->dk_name, sizeof(dkw->dkw_parent));
    630 		return dkwedge_add(dkw);
    631 
    632 	case DIOCDWEDGE:
    633 		if ((flag & FWRITE) == 0)
    634 			return EBADF;
    635 
    636 		dkw = data;
    637 		strlcpy(dkw->dkw_parent, dk->dk_name, sizeof(dkw->dkw_parent));
    638 		return dkwedge_del(dkw);
    639 
    640 	case DIOCLWEDGES:
    641 		return dkwedge_list(dk, data, l);
    642 
    643 	case DIOCMWEDGES:
    644 		if ((flag & FWRITE) == 0)
    645 			return EBADF;
    646 
    647 		dkwedge_discover(dk);
    648 		return 0;
    649 
    650 	default:
    651 		return EPASSTHROUGH;
    652 	}
    653 }
    654 
    655 void
    656 disk_set_info(device_t dev, struct disk *dk, const char *type)
    657 {
    658 	struct disk_geom *dg = &dk->dk_geom;
    659 
    660 	if (dg->dg_secsize == 0) {
    661 #ifdef DIAGNOSTIC
    662 		printf("%s: fixing 0 sector size\n", dk->dk_name);
    663 #endif
    664 		dg->dg_secsize = DEV_BSIZE;
    665 	}
    666 
    667 	dk->dk_blkshift = DK_BSIZE2BLKSHIFT(dg->dg_secsize);
    668 	dk->dk_byteshift = DK_BSIZE2BYTESHIFT(dg->dg_secsize);
    669 
    670 	if (dg->dg_secperunit == 0 && dg->dg_ncylinders == 0) {
    671 #ifdef DIAGNOSTIC
    672 		printf("%s: secperunit and ncylinders are zero\n", dk->dk_name);
    673 #endif
    674 		return;
    675 	}
    676 
    677 	if (dg->dg_secperunit == 0) {
    678 		if (dg->dg_nsectors == 0 || dg->dg_ntracks == 0) {
    679 #ifdef DIAGNOSTIC
    680 			printf("%s: secperunit and (sectors or tracks) "
    681 			    "are zero\n", dk->dk_name);
    682 #endif
    683 			return;
    684 		}
    685 		dg->dg_secperunit = (int64_t) dg->dg_nsectors *
    686 		    dg->dg_ntracks * dg->dg_ncylinders;
    687 	}
    688 
    689 	if (dg->dg_ncylinders == 0) {
    690 		if (dg->dg_ntracks && dg->dg_nsectors)
    691 			dg->dg_ncylinders = dg->dg_secperunit /
    692 			    (dg->dg_ntracks * dg->dg_nsectors);
    693 	}
    694 
    695 	prop_dictionary_t disk_info, odisk_info, geom;
    696 
    697 	disk_info = prop_dictionary_create();
    698 	geom = prop_dictionary_create();
    699 
    700 	prop_dictionary_set_uint64(geom, "sectors-per-unit",
    701 	    dg->dg_secperunit);
    702 
    703 	prop_dictionary_set_uint32(geom, "sector-size", dg->dg_secsize);
    704 
    705 	if (dg->dg_nsectors)
    706 		prop_dictionary_set_uint16(geom, "sectors-per-track",
    707 		    dg->dg_nsectors);
    708 
    709 	if (dg->dg_ntracks)
    710 		prop_dictionary_set_uint16(geom, "tracks-per-cylinder",
    711 		    dg->dg_ntracks);
    712 
    713 	if (dg->dg_ncylinders)
    714 		prop_dictionary_set_uint64(geom, "cylinders-per-unit",
    715 		    dg->dg_ncylinders);
    716 
    717 	prop_dictionary_set(disk_info, "geometry", geom);
    718 
    719 	if (type)
    720 		prop_dictionary_set_cstring_nocopy(disk_info, "type", type);
    721 
    722 	prop_object_release(geom);
    723 
    724 	odisk_info = dk->dk_info;
    725 	dk->dk_info = disk_info;
    726 
    727 	if (dev)
    728 		prop_dictionary_set(device_properties(dev), "disk-info",
    729 		    disk_info);
    730 
    731 	/*
    732 	 * Don't release disk_info here; we keep a reference to it.
    733 	 * disk_detach() will release it when we go away.
    734 	 */
    735 	if (odisk_info)
    736 		prop_object_release(odisk_info);
    737 }
    738