xref: /netbsd-src/sys/kern/subr_disk.c (revision da9817918ec7e88db2912a2882967c7570a83f47)
1 /*	$NetBSD: subr_disk.c,v 1.97 2009/05/20 03:26:21 dyoung 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 1.97 2009/05/20 03:26:21 dyoung 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/syslog.h>
77 #include <sys/disklabel.h>
78 #include <sys/disk.h>
79 #include <sys/sysctl.h>
80 #include <lib/libkern/libkern.h>
81 
82 /*
83  * Compute checksum for disk label.
84  */
85 u_int
86 dkcksum(struct disklabel *lp)
87 {
88 	return dkcksum_sized(lp, lp->d_npartitions);
89 }
90 
91 u_int
92 dkcksum_sized(struct disklabel *lp, size_t npartitions)
93 {
94 	u_short *start, *end;
95 	u_short sum = 0;
96 
97 	start = (u_short *)lp;
98 	end = (u_short *)&lp->d_partitions[npartitions];
99 	while (start < end)
100 		sum ^= *start++;
101 	return (sum);
102 }
103 
104 /*
105  * Disk error is the preface to plaintive error messages
106  * about failing disk transfers.  It prints messages of the form
107 
108 hp0g: hard error reading fsbn 12345 of 12344-12347 (hp0 bn %d cn %d tn %d sn %d)
109 
110  * if the offset of the error in the transfer and a disk label
111  * are both available.  blkdone should be -1 if the position of the error
112  * is unknown; the disklabel pointer may be null from drivers that have not
113  * been converted to use them.  The message is printed with printf
114  * if pri is LOG_PRINTF, otherwise it uses log at the specified priority.
115  * The message should be completed (with at least a newline) with printf
116  * or addlog, respectively.  There is no trailing space.
117  */
118 #ifndef PRIdaddr
119 #define PRIdaddr PRId64
120 #endif
121 void
122 diskerr(const struct buf *bp, const char *dname, const char *what, int pri,
123     int blkdone, const struct disklabel *lp)
124 {
125 	int unit = DISKUNIT(bp->b_dev), part = DISKPART(bp->b_dev);
126 	void (*pr)(const char *, ...);
127 	char partname = 'a' + part;
128 	daddr_t sn;
129 
130 	if (/*CONSTCOND*/0)
131 		/* Compiler will error this is the format is wrong... */
132 		printf("%" PRIdaddr, bp->b_blkno);
133 
134 	if (pri != LOG_PRINTF) {
135 		static const char fmt[] = "";
136 		log(pri, fmt);
137 		pr = addlog;
138 	} else
139 		pr = printf;
140 	(*pr)("%s%d%c: %s %sing fsbn ", dname, unit, partname, what,
141 	    bp->b_flags & B_READ ? "read" : "writ");
142 	sn = bp->b_blkno;
143 	if (bp->b_bcount <= DEV_BSIZE)
144 		(*pr)("%" PRIdaddr, sn);
145 	else {
146 		if (blkdone >= 0) {
147 			sn += blkdone;
148 			(*pr)("%" PRIdaddr " of ", sn);
149 		}
150 		(*pr)("%" PRIdaddr "-%" PRIdaddr "", bp->b_blkno,
151 		    bp->b_blkno + (bp->b_bcount - 1) / DEV_BSIZE);
152 	}
153 	if (lp && (blkdone >= 0 || bp->b_bcount <= lp->d_secsize)) {
154 		sn += lp->d_partitions[part].p_offset;
155 		(*pr)(" (%s%d bn %" PRIdaddr "; cn %" PRIdaddr "",
156 		    dname, unit, sn, sn / lp->d_secpercyl);
157 		sn %= lp->d_secpercyl;
158 		(*pr)(" tn %" PRIdaddr " sn %" PRIdaddr ")",
159 		    sn / lp->d_nsectors, sn % lp->d_nsectors);
160 	}
161 }
162 
163 /*
164  * Searches the iostatlist for the disk corresponding to the
165  * name provided.
166  */
167 struct disk *
168 disk_find(const char *name)
169 {
170 	struct io_stats *stat;
171 
172 	stat = iostat_find(name);
173 
174 	if ((stat != NULL) && (stat->io_type == IOSTAT_DISK))
175 		return stat->io_parent;
176 
177 	return (NULL);
178 }
179 
180 void
181 disk_init(struct disk *diskp, const char *name, const struct dkdriver *driver)
182 {
183 
184 	/*
185 	 * Initialize the wedge-related locks and other fields.
186 	 */
187 	mutex_init(&diskp->dk_rawlock, MUTEX_DEFAULT, IPL_NONE);
188 	mutex_init(&diskp->dk_openlock, MUTEX_DEFAULT, IPL_NONE);
189 	LIST_INIT(&diskp->dk_wedges);
190 	diskp->dk_nwedges = 0;
191 	diskp->dk_labelsector = LABELSECTOR;
192 	disk_blocksize(diskp, DEV_BSIZE);
193 	diskp->dk_name = name;
194 	diskp->dk_driver = driver;
195 }
196 
197 /*
198  * Attach a disk.
199  */
200 void
201 disk_attach(struct disk *diskp)
202 {
203 
204 	/*
205 	 * Allocate and initialize the disklabel structures.
206 	 */
207 	diskp->dk_label = kmem_zalloc(sizeof(struct disklabel), KM_SLEEP);
208 	diskp->dk_cpulabel = kmem_zalloc(sizeof(struct cpu_disklabel),
209 	    KM_SLEEP);
210 	if ((diskp->dk_label == NULL) || (diskp->dk_cpulabel == NULL))
211 		panic("disk_attach: can't allocate storage for disklabel");
212 
213 	/*
214 	 * Set up the stats collection.
215 	 */
216 	diskp->dk_stats = iostat_alloc(IOSTAT_DISK, diskp, diskp->dk_name);
217 }
218 
219 int
220 disk_begindetach(struct disk *dk, int (*lastclose)(device_t),
221     device_t self, int flags)
222 {
223 	int rc;
224 
225 	rc = 0;
226 	mutex_enter(&dk->dk_openlock);
227 	if (dk->dk_openmask == 0)
228 		;	/* nothing to do */
229 	else if ((flags & DETACH_FORCE) == 0)
230 		rc = EBUSY;
231 	else if (lastclose != NULL)
232 		rc = (*lastclose)(self);
233 	mutex_exit(&dk->dk_openlock);
234 
235 	return rc;
236 }
237 
238 /*
239  * Detach a disk.
240  */
241 void
242 disk_detach(struct disk *diskp)
243 {
244 
245 	/*
246 	 * Remove from the drivelist.
247 	 */
248 	iostat_free(diskp->dk_stats);
249 
250 	/*
251 	 * Release the disk-info dictionary.
252 	 */
253 	if (diskp->dk_info) {
254 		prop_object_release(diskp->dk_info);
255 		diskp->dk_info = NULL;
256 	}
257 
258 	/*
259 	 * Free the space used by the disklabel structures.
260 	 */
261 	kmem_free(diskp->dk_label, sizeof(*diskp->dk_label));
262 	kmem_free(diskp->dk_cpulabel, sizeof(*diskp->dk_cpulabel));
263 }
264 
265 void
266 disk_destroy(struct disk *diskp)
267 {
268 
269 	mutex_destroy(&diskp->dk_openlock);
270 	mutex_destroy(&diskp->dk_rawlock);
271 }
272 
273 /*
274  * Mark the disk as busy for metrics collection.
275  */
276 void
277 disk_busy(struct disk *diskp)
278 {
279 
280 	iostat_busy(diskp->dk_stats);
281 }
282 
283 /*
284  * Finished disk operations, gather metrics.
285  */
286 void
287 disk_unbusy(struct disk *diskp, long bcount, int read)
288 {
289 
290 	iostat_unbusy(diskp->dk_stats, bcount, read);
291 }
292 
293 /*
294  * Return true if disk has an I/O operation in flight.
295  */
296 bool
297 disk_isbusy(struct disk *diskp)
298 {
299 
300 	return iostat_isbusy(diskp->dk_stats);
301 }
302 
303 /*
304  * Set the physical blocksize of a disk, in bytes.
305  * Only necessary if blocksize != DEV_BSIZE.
306  */
307 void
308 disk_blocksize(struct disk *diskp, int blocksize)
309 {
310 
311 	diskp->dk_blkshift = DK_BSIZE2BLKSHIFT(blocksize);
312 	diskp->dk_byteshift = DK_BSIZE2BYTESHIFT(blocksize);
313 }
314 
315 /*
316  * Bounds checking against the media size, used for the raw partition.
317  * The sector size passed in should currently always be DEV_BSIZE,
318  * and the media size the size of the device in DEV_BSIZE sectors.
319  */
320 int
321 bounds_check_with_mediasize(struct buf *bp, int secsize, uint64_t mediasize)
322 {
323 	int64_t sz;
324 
325 	sz = howmany(bp->b_bcount, secsize);
326 
327 	if (bp->b_blkno + sz > mediasize) {
328 		sz = mediasize - bp->b_blkno;
329 		if (sz == 0) {
330 			/* If exactly at end of disk, return EOF. */
331 			bp->b_resid = bp->b_bcount;
332 			return 0;
333 		}
334 		if (sz < 0) {
335 			/* If past end of disk, return EINVAL. */
336 			bp->b_error = EINVAL;
337 			return 0;
338 		}
339 		/* Otherwise, truncate request. */
340 		bp->b_bcount = sz << DEV_BSHIFT;
341 	}
342 
343 	return 1;
344 }
345 
346 /*
347  * Determine the size of the transfer, and make sure it is
348  * within the boundaries of the partition. Adjust transfer
349  * if needed, and signal errors or early completion.
350  */
351 int
352 bounds_check_with_label(struct disk *dk, struct buf *bp, int wlabel)
353 {
354 	struct disklabel *lp = dk->dk_label;
355 	struct partition *p = lp->d_partitions + DISKPART(bp->b_dev);
356 	uint64_t p_size, p_offset, labelsector;
357 	int64_t sz;
358 
359 	/* Protect against division by zero. XXX: Should never happen?!?! */
360 	if (lp->d_secpercyl == 0) {
361 		bp->b_error = EINVAL;
362 		return -1;
363 	}
364 
365 	p_size = p->p_size << dk->dk_blkshift;
366 	p_offset = p->p_offset << dk->dk_blkshift;
367 #if RAW_PART == 3
368 	labelsector = lp->d_partitions[2].p_offset;
369 #else
370 	labelsector = lp->d_partitions[RAW_PART].p_offset;
371 #endif
372 	labelsector = (labelsector + dk->dk_labelsector) << dk->dk_blkshift;
373 
374 	sz = howmany(bp->b_bcount, DEV_BSIZE);
375 	if ((bp->b_blkno + sz) > p_size) {
376 		sz = p_size - bp->b_blkno;
377 		if (sz == 0) {
378 			/* If exactly at end of disk, return EOF. */
379 			bp->b_resid = bp->b_bcount;
380 			return 0;
381 		}
382 		if (sz < 0) {
383 			/* If past end of disk, return EINVAL. */
384 			bp->b_error = EINVAL;
385 			return -1;
386 		}
387 		/* Otherwise, truncate request. */
388 		bp->b_bcount = sz << DEV_BSHIFT;
389 	}
390 
391 	/* Overwriting disk label? */
392 	if (bp->b_blkno + p_offset <= labelsector &&
393 	    bp->b_blkno + p_offset + sz > labelsector &&
394 	    (bp->b_flags & B_READ) == 0 && !wlabel) {
395 		bp->b_error = EROFS;
396 		return -1;
397 	}
398 
399 	/* calculate cylinder for disksort to order transfers with */
400 	bp->b_cylinder = (bp->b_blkno + p->p_offset) /
401 	    (lp->d_secsize / DEV_BSIZE) / lp->d_secpercyl;
402 	return 1;
403 }
404 
405 int
406 disk_read_sectors(void (*strat)(struct buf *), const struct disklabel *lp,
407     struct buf *bp, unsigned int sector, int count)
408 {
409 	bp->b_blkno = sector;
410 	bp->b_bcount = count * lp->d_secsize;
411 	bp->b_flags = (bp->b_flags & ~B_WRITE) | B_READ;
412 	bp->b_oflags &= ~BO_DONE;
413 	bp->b_cylinder = sector / lp->d_secpercyl;
414 	(*strat)(bp);
415 	return biowait(bp);
416 }
417 
418 const char *
419 convertdisklabel(struct disklabel *lp, void (*strat)(struct buf *),
420     struct buf *bp, uint32_t secperunit)
421 {
422 	struct partition rp, *altp, *p;
423 	int geom_ok;
424 
425 	memset(&rp, 0, sizeof(rp));
426 	rp.p_size = secperunit;
427 	rp.p_fstype = FS_UNUSED;
428 
429 	/* If we can seek to d_secperunit - 1, believe the disk geometry. */
430 	if (secperunit != 0 &&
431 	    disk_read_sectors(strat, lp, bp, secperunit - 1, 1) == 0)
432 		geom_ok = 1;
433 	else
434 		geom_ok = 0;
435 
436 #if 0
437 	printf("%s: secperunit (%" PRIu32 ") %s\n", __func__,
438 	    secperunit, geom_ok ? "ok" : "not ok");
439 #endif
440 
441 	p = &lp->d_partitions[RAW_PART];
442 	if (RAW_PART == 'c' - 'a')
443 		altp = &lp->d_partitions['d' - 'a'];
444 	else
445 		altp = &lp->d_partitions['c' - 'a'];
446 
447 	if (lp->d_npartitions > RAW_PART && p->p_offset == 0 && p->p_size != 0)
448 		;	/* already a raw partition */
449 	else if (lp->d_npartitions > MAX('c', 'd') - 'a' &&
450 		 altp->p_offset == 0 && altp->p_size != 0) {
451 		/* alternate partition ('c' or 'd') is suitable for raw slot,
452 		 * swap with 'd' or 'c'.
453 		 */
454 		rp = *p;
455 		*p = *altp;
456 		*altp = rp;
457 	} else if (lp->d_npartitions <= RAW_PART &&
458 	           lp->d_npartitions > 'c' - 'a') {
459 		/* No raw partition is present, but the alternate is present.
460 		 * Copy alternate to raw partition.
461 		 */
462 		lp->d_npartitions = RAW_PART + 1;
463 		*p = *altp;
464 	} else if (!geom_ok)
465 		return "no raw partition and disk reports bad geometry";
466 	else if (lp->d_npartitions <= RAW_PART) {
467 		memset(&lp->d_partitions[lp->d_npartitions], 0,
468 		    sizeof(struct partition) * (RAW_PART - lp->d_npartitions));
469 		*p = rp;
470 		lp->d_npartitions = RAW_PART + 1;
471 	} else if (lp->d_npartitions < MAXPARTITIONS) {
472 		memmove(p + 1, p,
473 		    sizeof(struct partition) * (lp->d_npartitions - RAW_PART));
474 		*p = rp;
475 		lp->d_npartitions++;
476 	} else
477 		return "no raw partition and partition table is full";
478 	return NULL;
479 }
480 
481 /*
482  * disk_ioctl --
483  *	Generic disk ioctl handling.
484  */
485 int
486 disk_ioctl(struct disk *diskp, u_long cmd, void *data, int flag,
487 	   struct lwp *l)
488 {
489 	int error;
490 
491 	switch (cmd) {
492 	case DIOCGDISKINFO:
493 	    {
494 		struct plistref *pref = (struct plistref *) data;
495 
496 		if (diskp->dk_info == NULL)
497 			error = ENOTSUP;
498 		else
499 			error = prop_dictionary_copyout_ioctl(pref, cmd,
500 							diskp->dk_info);
501 		break;
502 	    }
503 
504 	default:
505 		error = EPASSTHROUGH;
506 	}
507 
508 	return (error);
509 }
510