xref: /dragonfly/sys/kern/subr_disklabel64.c (revision 28c26f7e)
1 /*
2  * Copyright (c) 2007 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  * $DragonFly: src/sys/kern/subr_disklabel64.c,v 1.5 2007/07/20 17:21:51 dillon Exp $
35  */
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/conf.h>
41 #include <sys/disklabel.h>
42 #include <sys/disklabel64.h>
43 #include <sys/diskslice.h>
44 #include <sys/disk.h>
45 #include <sys/kern_syscall.h>
46 #include <sys/buf2.h>
47 
48 /*
49  * Retrieve the partition start and extent, in blocks.  Return 0 on success,
50  * EINVAL on error.
51  */
52 static int
53 l64_getpartbounds(struct diskslices *ssp, disklabel_t lp, u_int32_t part,
54 		  u_int64_t *start, u_int64_t *blocks)
55 {
56 	struct partition64 *pp;
57 
58 	if (part >= lp.lab64->d_npartitions)
59 		return (EINVAL);
60 
61 	pp = &lp.lab64->d_partitions[part];
62 
63 	if ((pp->p_boffset & (ssp->dss_secsize - 1)) ||
64 	    (pp->p_bsize & (ssp->dss_secsize - 1))) {
65 		return (EINVAL);
66 	}
67 	*start = pp->p_boffset / ssp->dss_secsize;
68 	*blocks = pp->p_bsize / ssp->dss_secsize;
69 	return(0);
70 }
71 
72 /*
73  * Get the filesystem type XXX - diskslices code needs to use uuids
74  */
75 static void
76 l64_loadpartinfo(disklabel_t lp, u_int32_t part, struct partinfo *dpart)
77 {
78 	struct partition64 *pp;
79 	const size_t uuid_size = sizeof(struct uuid);
80 
81 	if (part < lp.lab64->d_npartitions) {
82 		pp = &lp.lab64->d_partitions[part];
83 		dpart->fstype_uuid = pp->p_type_uuid;
84 		dpart->storage_uuid = pp->p_stor_uuid;
85 		dpart->fstype = pp->p_fstype;
86 	} else {
87 		bzero(&dpart->fstype_uuid, uuid_size);
88 		bzero(&dpart->storage_uuid, uuid_size);
89 		dpart->fstype = 0;
90 	}
91 }
92 
93 /*
94  * Get the number of partitions
95  */
96 static u_int32_t
97 l64_getnumparts(disklabel_t lp)
98 {
99 	return(lp.lab64->d_npartitions);
100 }
101 
102 /*
103  * Attempt to read a disk label from a device.  64 bit disklabels are
104  * sector-agnostic and begin at offset 0 on the device.  64 bit disklabels
105  * may only be used with GPT partitioning schemes.
106  *
107  * Returns NULL on sucess, and an error string on failure.
108  */
109 static const char *
110 l64_readdisklabel(cdev_t dev, struct diskslice *sp, disklabel_t *lpp,
111 		  struct disk_info *info)
112 {
113 	struct buf *bp;
114 	struct disklabel64 *dlp;
115 	const char *msg;
116 	uint32_t savecrc;
117 	size_t dlpcrcsize;
118 	size_t bpsize;
119 	int secsize;
120 
121 	/*
122 	 * XXX I/O size is subject to device DMA limitations
123 	 */
124 	secsize = info->d_media_blksize;
125 	bpsize = (sizeof(*dlp) + secsize - 1) & ~(secsize - 1);
126 
127 	bp = geteblk(bpsize);
128 	bp->b_bio1.bio_offset = 0;
129 	bp->b_bio1.bio_done = biodone_sync;
130 	bp->b_bio1.bio_flags |= BIO_SYNC;
131 	bp->b_bcount = bpsize;
132 	bp->b_flags &= ~B_INVAL;
133 	bp->b_cmd = BUF_CMD_READ;
134 	dev_dstrategy(dev, &bp->b_bio1);
135 
136 	if (biowait(&bp->b_bio1, "labrd")) {
137 		msg = "I/O error";
138 	} else {
139 		dlp = (struct disklabel64 *)bp->b_data;
140 		dlpcrcsize = offsetof(struct disklabel64,
141 				      d_partitions[dlp->d_npartitions]) -
142 			     offsetof(struct disklabel64, d_magic);
143 		savecrc = dlp->d_crc;
144 		dlp->d_crc = 0;
145 		if (dlp->d_magic != DISKMAGIC64) {
146 			msg = "no disk label";
147 		} else if (dlp->d_npartitions > MAXPARTITIONS64) {
148 			msg = "disklabel64 corrupted, too many partitions";
149 		} else if (savecrc != crc32(&dlp->d_magic, dlpcrcsize)) {
150 			msg = "disklabel64 corrupted, bad CRC";
151 		} else {
152 			dlp->d_crc = savecrc;
153 			(*lpp).lab64 = kmalloc(sizeof(*dlp),
154 					       M_DEVBUF, M_WAITOK|M_ZERO);
155 			*(*lpp).lab64 = *dlp;
156 			msg = NULL;
157 		}
158 	}
159 	bp->b_flags |= B_INVAL | B_AGE;
160 	brelse(bp);
161 	return (msg);
162 }
163 
164 /*
165  * If everything is good, copy olpx to nlpx.  Check to see if any
166  * open partitions would change.
167  */
168 static int
169 l64_setdisklabel(disklabel_t olpx, disklabel_t nlpx, struct diskslices *ssp,
170 		 struct diskslice *sp, u_int32_t *openmask)
171 {
172 	struct disklabel64 *olp, *nlp;
173 	struct partition64 *opp, *npp;
174 	uint32_t savecrc;
175 	uint64_t slicebsize;
176 	size_t nlpcrcsize;
177 	int i;
178 
179 	olp = olpx.lab64;
180 	nlp = nlpx.lab64;
181 
182 	slicebsize = (uint64_t)sp->ds_size * ssp->dss_secsize;
183 
184 	if (nlp->d_magic != DISKMAGIC64)
185 		return (EINVAL);
186 	if (nlp->d_npartitions > MAXPARTITIONS64)
187 		return (EINVAL);
188 	savecrc = nlp->d_crc;
189 	nlp->d_crc = 0;
190 	nlpcrcsize = offsetof(struct disklabel64,
191 			      d_partitions[nlp->d_npartitions]) -
192 		     offsetof(struct disklabel64, d_magic);
193 	if (crc32(&nlp->d_magic, nlpcrcsize) != savecrc) {
194 		nlp->d_crc = savecrc;
195 		return (EINVAL);
196 	}
197 	nlp->d_crc = savecrc;
198 
199 	/*
200 	 * Check if open partitions have changed
201 	 */
202 	i = 0;
203 	while (i < MAXPARTITIONS64) {
204 		if (openmask[i >> 5] == 0) {
205 			i += 32;
206 			continue;
207 		}
208 		if ((openmask[i >> 5] & (1 << (i & 31))) == 0) {
209 			++i;
210 			continue;
211 		}
212 		if (nlp->d_npartitions <= i)
213 			return (EBUSY);
214 		opp = &olp->d_partitions[i];
215 		npp = &nlp->d_partitions[i];
216 		if (npp->p_boffset != opp->p_boffset ||
217 		    npp->p_bsize < opp->p_bsize) {
218 			return (EBUSY);
219 		}
220 
221 		/*
222 		 * Do not allow p_type_uuid or p_stor_uuid to change if
223 		 * the partition is currently open.
224 		 */
225 		if (bcmp(&npp->p_type_uuid, &opp->p_type_uuid,
226 		     sizeof(npp->p_type_uuid)) != 0) {
227 			return (EBUSY);
228 		}
229 		if (bcmp(&npp->p_stor_uuid, &opp->p_stor_uuid,
230 		     sizeof(npp->p_stor_uuid)) != 0) {
231 			return (EBUSY);
232 		}
233 		++i;
234 	}
235 
236 	/*
237 	 * Make sure the label and partition offsets and sizes are sane.
238 	 */
239 	if (nlp->d_total_size > slicebsize)
240 		return (ENOSPC);
241 	if (nlp->d_total_size & (ssp->dss_secsize - 1))
242 		return (EINVAL);
243 	if (nlp->d_bbase & (ssp->dss_secsize - 1))
244 		return (EINVAL);
245 	if (nlp->d_pbase & (ssp->dss_secsize - 1))
246 		return (EINVAL);
247 	if (nlp->d_pstop & (ssp->dss_secsize - 1))
248 		return (EINVAL);
249 	if (nlp->d_abase & (ssp->dss_secsize - 1))
250 		return (EINVAL);
251 
252 	for (i = 0; i < nlp->d_npartitions; ++i) {
253 		npp = &nlp->d_partitions[i];
254 		if (npp->p_bsize == 0) {
255 			if (npp->p_boffset != 0)
256 				return (EINVAL);
257 			continue;
258 		}
259 		if (npp->p_boffset & (ssp->dss_secsize - 1))
260 			return (EINVAL);
261 		if (npp->p_bsize & (ssp->dss_secsize - 1))
262 			return (EINVAL);
263 		if (npp->p_boffset < nlp->d_pbase)
264 			return (ENOSPC);
265 		if (npp->p_boffset + npp->p_bsize > nlp->d_total_size)
266 			return (ENOSPC);
267 	}
268 
269 	/*
270 	 * Structurally we may add code to make modifications above in the
271 	 * future, so regenerate the crc anyway.
272 	 */
273 	nlp->d_crc = 0;
274 	nlp->d_crc = crc32(&nlp->d_magic, nlpcrcsize);
275 	*olp = *nlp;
276 
277 	return (0);
278 }
279 
280 /*
281  * Write disk label back to device after modification.
282  */
283 static int
284 l64_writedisklabel(cdev_t dev, struct diskslices *ssp,
285 		   struct diskslice *sp, disklabel_t lpx)
286 {
287 	struct disklabel64 *lp;
288 	struct disklabel64 *dlp;
289 	struct buf *bp;
290 	int error = 0;
291 	size_t bpsize;
292 	int secsize;
293 
294 	lp = lpx.lab64;
295 
296 	/*
297 	 * XXX I/O size is subject to device DMA limitations
298 	 */
299 	secsize = ssp->dss_secsize;
300 	bpsize = (sizeof(*lp) + secsize - 1) & ~(secsize - 1);
301 
302 	bp = geteblk(bpsize);
303 	bp->b_bio1.bio_offset = 0;
304 	bp->b_bio1.bio_done = biodone_sync;
305 	bp->b_bio1.bio_flags |= BIO_SYNC;
306 	bp->b_bcount = bpsize;
307 
308 	/*
309 	 * Because our I/O is larger then the label, and because we do not
310 	 * write the d_reserved0[] area, do a read-modify-write.
311 	 */
312 	bp->b_flags &= ~B_INVAL;
313 	bp->b_cmd = BUF_CMD_READ;
314 	KKASSERT(dkpart(dev) == WHOLE_SLICE_PART);
315 	dev_dstrategy(dev, &bp->b_bio1);
316 	error = biowait(&bp->b_bio1, "labrd");
317 	if (error)
318 		goto done;
319 
320 	dlp = (void *)bp->b_data;
321 	bcopy(&lp->d_magic, &dlp->d_magic,
322 	      sizeof(*lp) - offsetof(struct disklabel64, d_magic));
323 	bp->b_cmd = BUF_CMD_WRITE;
324 	bp->b_bio1.bio_done = biodone_sync;
325 	bp->b_bio1.bio_flags |= BIO_SYNC;
326 	KKASSERT(dkpart(dev) == WHOLE_SLICE_PART);
327 	dev_dstrategy(dev, &bp->b_bio1);
328 	error = biowait(&bp->b_bio1, "labwr");
329 done:
330 	bp->b_flags |= B_INVAL | B_AGE;
331 	brelse(bp);
332 	return (error);
333 }
334 
335 /*
336  * Create a disklabel based on a disk_info structure for the purposes of
337  * DSO_COMPATLABEL - cases where no real label exists on the storage medium.
338  *
339  * If a diskslice is passed, the label is truncated to the slice.
340  *
341  * NOTE!  This is not a legal label because d_bbase and d_pbase are both
342  * set to 0.
343  */
344 static disklabel_t
345 l64_clone_label(struct disk_info *info, struct diskslice *sp)
346 {
347 	struct disklabel64 *lp;
348 	disklabel_t res;
349 	uint32_t blksize = info->d_media_blksize;
350 	size_t lpcrcsize;
351 
352 	lp = kmalloc(sizeof *lp, M_DEVBUF, M_WAITOK | M_ZERO);
353 
354 	if (sp)
355 		lp->d_total_size = (uint64_t)sp->ds_size * blksize;
356 	else
357 		lp->d_total_size = info->d_media_blocks * blksize;
358 
359 	lp->d_magic = DISKMAGIC64;
360 	lp->d_align = blksize;
361 	lp->d_npartitions = MAXPARTITIONS64;
362 	lp->d_pstop = lp->d_total_size;
363 
364 	/*
365 	 * Create a dummy 'c' part and a dummy 'a' part (if requested).
366 	 * Note that the 'c' part is really a hack.  64 bit disklabels
367 	 * do not use 'c' to mean the raw partition.
368 	 */
369 
370 	lp->d_partitions[2].p_boffset = 0;
371 	lp->d_partitions[2].p_bsize = lp->d_total_size;
372 	/* XXX SET FS TYPE */
373 
374 	if (info->d_dsflags & DSO_COMPATPARTA) {
375 		lp->d_partitions[0].p_boffset = 0;
376 		lp->d_partitions[0].p_bsize = lp->d_total_size;
377 		/* XXX SET FS TYPE */
378 	}
379 
380 	lpcrcsize = offsetof(struct disklabel64,
381 			     d_partitions[lp->d_npartitions]) -
382 		    offsetof(struct disklabel64, d_magic);
383 
384 	lp->d_crc = crc32(&lp->d_magic, lpcrcsize);
385 	res.lab64 = lp;
386 	return (res);
387 }
388 
389 /*
390  * Create a virgin disklabel64 suitable for writing to the media.
391  *
392  * disklabel64 always reserves 32KB for a boot area and leaves room
393  * for up to RESPARTITIONS64 partitions.
394  */
395 static void
396 l64_makevirginlabel(disklabel_t lpx, struct diskslices *ssp,
397 		    struct diskslice *sp, struct disk_info *info)
398 {
399 	struct disklabel64 *lp = lpx.lab64;
400 	struct partition64 *pp;
401 	uint32_t blksize;
402 	uint32_t ressize;
403 	uint64_t blkmask;	/* 64 bits so we can ~ */
404 	size_t lpcrcsize;
405 
406 	/*
407 	 * Setup the initial label.  Use of a block size of at least 4KB
408 	 * for calculating the initial reserved areas to allow some degree
409 	 * of portability between media with different sector sizes.
410 	 *
411 	 * Note that the modified blksize is stored in d_align as a hint
412 	 * to the disklabeling program.
413 	 */
414 	bzero(lp, sizeof(*lp));
415 	if ((blksize = info->d_media_blksize) < 4096)
416 		blksize = 4096;
417 	blkmask = blksize - 1;
418 
419 	if (sp)
420 		lp->d_total_size = (uint64_t)sp->ds_size * ssp->dss_secsize;
421 	else
422 		lp->d_total_size = info->d_media_blocks * info->d_media_blksize;
423 
424 	lp->d_magic = DISKMAGIC64;
425 	lp->d_align = blksize;
426 	lp->d_npartitions = MAXPARTITIONS64;
427 	kern_uuidgen(&lp->d_stor_uuid, 1);
428 
429 	ressize = offsetof(struct disklabel64, d_partitions[RESPARTITIONS64]);
430 	ressize = (ressize + (uint32_t)blkmask) & ~blkmask;
431 
432 	lp->d_bbase = ressize;
433 	lp->d_pbase = lp->d_bbase + ((32768 + blkmask) & ~blkmask);
434 	lp->d_pstop = (lp->d_total_size - lp->d_bbase) & ~blkmask;
435 	lp->d_abase = lp->d_pstop;
436 
437 	/*
438 	 * All partitions are left empty unless DSO_COMPATPARTA is set
439 	 */
440 
441 	if (info->d_dsflags & DSO_COMPATPARTA) {
442 		pp = &lp->d_partitions[0];
443 		pp->p_boffset = lp->d_pbase;
444 		pp->p_bsize = lp->d_pstop - lp->d_pbase;
445 		/* XXX SET FS TYPE */
446 	}
447 
448 	lpcrcsize = offsetof(struct disklabel64,
449 			     d_partitions[lp->d_npartitions]) -
450 		    offsetof(struct disklabel64, d_magic);
451 	lp->d_crc = crc32(&lp->d_magic, lpcrcsize);
452 }
453 
454 /*
455  * Set the number of blocks at the beginning of the slice which have
456  * been reserved for label operations.  This area will be write-protected
457  * when accessed via the slice.
458  *
459  * For now just protect the label area proper.  Do not protect the
460  * boot area.  Note partitions in 64 bit disklabels do not overlap
461  * the disklabel or boot area.
462  */
463 static void
464 l64_adjust_label_reserved(struct diskslices *ssp, int slice,
465 			  struct diskslice *sp)
466 {
467 	struct disklabel64 *lp = sp->ds_label.lab64;
468 
469 	sp->ds_reserved = lp->d_bbase / ssp->dss_secsize;
470 }
471 
472 struct disklabel_ops disklabel64_ops = {
473 	.labelsize = sizeof(struct disklabel64),
474 	.op_readdisklabel = l64_readdisklabel,
475 	.op_setdisklabel = l64_setdisklabel,
476 	.op_writedisklabel = l64_writedisklabel,
477 	.op_clone_label = l64_clone_label,
478 	.op_adjust_label_reserved = l64_adjust_label_reserved,
479 	.op_getpartbounds = l64_getpartbounds,
480 	.op_loadpartinfo = l64_loadpartinfo,
481 	.op_getnumparts = l64_getnumparts,
482 	.op_makevirginlabel = l64_makevirginlabel
483 };
484 
485