xref: /dflybsd-src/sys/kern/subr_disklabel64.c (revision cd29885abfb8f68adb0c082e313b891156d66964)
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 part;
178 	int i;
179 
180 	olp = olpx.lab64;
181 	nlp = nlpx.lab64;
182 
183 	slicebsize = (uint64_t)sp->ds_size * ssp->dss_secsize;
184 
185 	if (nlp->d_magic != DISKMAGIC64)
186 		return (EINVAL);
187 	if (nlp->d_npartitions > MAXPARTITIONS64)
188 		return (EINVAL);
189 	savecrc = nlp->d_crc;
190 	nlp->d_crc = 0;
191 	nlpcrcsize = offsetof(struct disklabel64,
192 			      d_partitions[nlp->d_npartitions]) -
193 		     offsetof(struct disklabel64, d_magic);
194 	if (crc32(&nlp->d_magic, nlpcrcsize) != savecrc) {
195 		nlp->d_crc = savecrc;
196 		return (EINVAL);
197 	}
198 	nlp->d_crc = savecrc;
199 
200 	/*
201 	 * Check if open partitions have changed
202 	 */
203 	i = 0;
204 	while (i < 128) {
205 		if (openmask[i >> 5] == 0) {
206 			i += 32;
207 			continue;
208 		}
209 		if ((openmask[i >> 5] & (1 << (i & 31))) == 0) {
210 			++i;
211 			continue;
212 		}
213 		if (nlp->d_npartitions <= i)
214 			return (EBUSY);
215 		opp = &olp->d_partitions[i];
216 		npp = &nlp->d_partitions[i];
217 		if (npp->p_boffset != opp->p_boffset ||
218 		    npp->p_bsize < opp->p_bsize) {
219 			return (EBUSY);
220 		}
221 
222 		/*
223 		 * Do not allow p_type_uuid or p_stor_uuid to change if
224 		 * the partition is currently open.
225 		 */
226 		if (bcmp(&npp->p_type_uuid, &opp->p_type_uuid,
227 		     sizeof(npp->p_type_uuid)) != 0) {
228 			return (EBUSY);
229 		}
230 		if (bcmp(&npp->p_stor_uuid, &opp->p_stor_uuid,
231 		     sizeof(npp->p_stor_uuid)) != 0) {
232 			return (EBUSY);
233 		}
234 		++i;
235 	}
236 
237 	/*
238 	 * Make sure the label and partition offsets and sizes are sane.
239 	 */
240 	if (nlp->d_total_size > slicebsize)
241 		return (ENOSPC);
242 	if (nlp->d_total_size & (ssp->dss_secsize - 1))
243 		return (EINVAL);
244 	if (nlp->d_bbase & (ssp->dss_secsize - 1))
245 		return (EINVAL);
246 	if (nlp->d_pbase & (ssp->dss_secsize - 1))
247 		return (EINVAL);
248 	if (nlp->d_pstop & (ssp->dss_secsize - 1))
249 		return (EINVAL);
250 	if (nlp->d_abase & (ssp->dss_secsize - 1))
251 		return (EINVAL);
252 
253 	for (part = 0; part < nlp->d_npartitions; ++part) {
254 		npp = &nlp->d_partitions[i];
255 		if (npp->p_bsize == 0) {
256 			if (npp->p_boffset != 0)
257 				return (EINVAL);
258 			continue;
259 		}
260 		if (npp->p_boffset & (ssp->dss_secsize - 1))
261 			return (EINVAL);
262 		if (npp->p_bsize & (ssp->dss_secsize - 1))
263 			return (EINVAL);
264 		if (npp->p_boffset < nlp->d_pbase)
265 			return (ENOSPC);
266 		if (npp->p_boffset + npp->p_bsize > nlp->d_total_size)
267 			return (ENOSPC);
268 	}
269 
270 	/*
271 	 * Structurally we may add code to make modifications above in the
272 	 * future, so regenerate the crc anyway.
273 	 */
274 	nlp->d_crc = 0;
275 	nlp->d_crc = crc32(&nlp->d_magic, nlpcrcsize);
276 	*olp = *nlp;
277 
278 	return (0);
279 }
280 
281 /*
282  * Write disk label back to device after modification.
283  */
284 static int
285 l64_writedisklabel(cdev_t dev, struct diskslices *ssp,
286 		   struct diskslice *sp, disklabel_t lpx)
287 {
288 	struct disklabel64 *lp;
289 	struct disklabel64 *dlp;
290 	struct buf *bp;
291 	int error = 0;
292 	size_t bpsize;
293 	int secsize;
294 
295 	lp = lpx.lab64;
296 
297 	kprintf("this is l64_writedisklabel: part: %d, slice: %d\n", dkpart(dev), dkslice(dev));
298 	kprintf("Avoiding disaster and returning now\n");
299 	return 0;
300 
301 	/*
302 	 * XXX I/O size is subject to device DMA limitations
303 	 */
304 	secsize = ssp->dss_secsize;
305 	bpsize = (sizeof(*lp) + secsize - 1) & ~(secsize - 1);
306 
307 	bp = geteblk(bpsize);
308 	bp->b_bio1.bio_offset = 0;
309 	bp->b_bio1.bio_done = biodone_sync;
310 	bp->b_bio1.bio_flags |= BIO_SYNC;
311 	bp->b_bcount = bpsize;
312 
313 	/*
314 	 * Because our I/O is larger then the label, and because we do not
315 	 * write the d_reserved0[] area, do a read-modify-write.
316 	 */
317 	bp->b_flags &= ~B_INVAL;
318 	bp->b_cmd = BUF_CMD_READ;
319 	dev_dstrategy(dkmodpart(dev, WHOLE_SLICE_PART), &bp->b_bio1);
320 	error = biowait(&bp->b_bio1, "labrd");
321 	if (error)
322 		goto done;
323 
324 	dlp = (void *)bp->b_data;
325 	bcopy(&lp->d_magic, &dlp->d_magic,
326 	      sizeof(*lp) - offsetof(struct disklabel64, d_magic));
327 	bp->b_cmd = BUF_CMD_WRITE;
328 	bp->b_bio1.bio_done = biodone_sync;
329 	bp->b_bio1.bio_flags |= BIO_SYNC;
330 	dev_dstrategy(dkmodpart(dev, WHOLE_SLICE_PART), &bp->b_bio1);
331 	error = biowait(&bp->b_bio1, "labwr");
332 done:
333 	bp->b_flags |= B_INVAL | B_AGE;
334 	brelse(bp);
335 	return (error);
336 }
337 
338 /*
339  * Create a disklabel based on a disk_info structure for the purposes of
340  * DSO_COMPATLABEL - cases where no real label exists on the storage medium.
341  *
342  * If a diskslice is passed, the label is truncated to the slice.
343  *
344  * NOTE!  This is not a legal label because d_bbase and d_pbase are both
345  * set to 0.
346  */
347 static disklabel_t
348 l64_clone_label(struct disk_info *info, struct diskslice *sp)
349 {
350 	struct disklabel64 *lp;
351 	disklabel_t res;
352 	uint32_t blksize = info->d_media_blksize;
353 	size_t lpcrcsize;
354 
355 	lp = kmalloc(sizeof *lp, M_DEVBUF, M_WAITOK | M_ZERO);
356 
357 	if (sp)
358 		lp->d_total_size = (uint64_t)sp->ds_size * blksize;
359 	else
360 		lp->d_total_size = info->d_media_blocks * blksize;
361 
362 	lp->d_magic = DISKMAGIC64;
363 	lp->d_align = blksize;
364 	lp->d_npartitions = MAXPARTITIONS64;
365 	lp->d_pstop = lp->d_total_size;
366 
367 	/*
368 	 * Create a dummy 'c' part and a dummy 'a' part (if requested).
369 	 * Note that the 'c' part is really a hack.  64 bit disklabels
370 	 * do not use 'c' to mean the raw partition.
371 	 */
372 
373 	lp->d_partitions[2].p_boffset = 0;
374 	lp->d_partitions[2].p_bsize = lp->d_total_size;
375 	/* XXX SET FS TYPE */
376 
377 	if (info->d_dsflags & DSO_COMPATPARTA) {
378 		lp->d_partitions[0].p_boffset = 0;
379 		lp->d_partitions[0].p_bsize = lp->d_total_size;
380 		/* XXX SET FS TYPE */
381 	}
382 
383 	lpcrcsize = offsetof(struct disklabel64,
384 			     d_partitions[lp->d_npartitions]) -
385 		    offsetof(struct disklabel64, d_magic);
386 
387 	lp->d_crc = crc32(&lp->d_magic, lpcrcsize);
388 	res.lab64 = lp;
389 	return (res);
390 }
391 
392 /*
393  * Create a virgin disklabel64 suitable for writing to the media.
394  *
395  * disklabel64 always reserves 32KB for a boot area and leaves room
396  * for up to RESPARTITIONS64 partitions.
397  */
398 static void
399 l64_makevirginlabel(disklabel_t lpx, struct diskslices *ssp,
400 		    struct diskslice *sp, struct disk_info *info)
401 {
402 	struct disklabel64 *lp = lpx.lab64;
403 	struct partition64 *pp;
404 	uint32_t blksize;
405 	uint32_t ressize;
406 	uint64_t blkmask;	/* 64 bits so we can ~ */
407 	size_t lpcrcsize;
408 
409 	/*
410 	 * Setup the initial label.  Use of a block size of at least 4KB
411 	 * for calculating the initial reserved areas to allow some degree
412 	 * of portability between media with different sector sizes.
413 	 *
414 	 * Note that the modified blksize is stored in d_align as a hint
415 	 * to the disklabeling program.
416 	 */
417 	bzero(lp, sizeof(*lp));
418 	if ((blksize = info->d_media_blksize) < 4096)
419 		blksize = 4096;
420 	blkmask = blksize - 1;
421 
422 	if (sp)
423 		lp->d_total_size = (uint64_t)sp->ds_size * ssp->dss_secsize;
424 	else
425 		lp->d_total_size = info->d_media_blocks * info->d_media_blksize;
426 
427 	lp->d_magic = DISKMAGIC64;
428 	lp->d_align = blksize;
429 	lp->d_npartitions = MAXPARTITIONS64;
430 	kern_uuidgen(&lp->d_stor_uuid, 1);
431 
432 	ressize = offsetof(struct disklabel64, d_partitions[RESPARTITIONS64]);
433 	ressize = (ressize + (uint32_t)blkmask) & ~blkmask;
434 
435 	lp->d_bbase = ressize;
436 	lp->d_pbase = lp->d_bbase + ((32768 + blkmask) & ~blkmask);
437 	lp->d_pstop = (lp->d_total_size - lp->d_bbase) & ~blkmask;
438 	lp->d_abase = lp->d_pstop;
439 
440 	/*
441 	 * All partitions are left empty unless DSO_COMPATPARTA is set
442 	 */
443 
444 	if (info->d_dsflags & DSO_COMPATPARTA) {
445 		pp = &lp->d_partitions[0];
446 		pp->p_boffset = lp->d_pbase;
447 		pp->p_bsize = lp->d_pstop - lp->d_pbase;
448 		/* XXX SET FS TYPE */
449 	}
450 
451 	lpcrcsize = offsetof(struct disklabel64,
452 			     d_partitions[lp->d_npartitions]) -
453 		    offsetof(struct disklabel64, d_magic);
454 	lp->d_crc = crc32(&lp->d_magic, lpcrcsize);
455 }
456 
457 /*
458  * Set the number of blocks at the beginning of the slice which have
459  * been reserved for label operations.  This area will be write-protected
460  * when accessed via the slice.
461  *
462  * For now just protect the label area proper.  Do not protect the
463  * boot area.  Note partitions in 64 bit disklabels do not overlap
464  * the disklabel or boot area.
465  */
466 static void
467 l64_adjust_label_reserved(struct diskslices *ssp, int slice,
468 			  struct diskslice *sp)
469 {
470 	struct disklabel64 *lp = sp->ds_label.lab64;
471 
472 	sp->ds_reserved = lp->d_bbase / ssp->dss_secsize;
473 }
474 
475 struct disklabel_ops disklabel64_ops = {
476 	.labelsize = sizeof(struct disklabel64),
477 	.op_readdisklabel = l64_readdisklabel,
478 	.op_setdisklabel = l64_setdisklabel,
479 	.op_writedisklabel = l64_writedisklabel,
480 	.op_clone_label = l64_clone_label,
481 	.op_adjust_label_reserved = l64_adjust_label_reserved,
482 	.op_getpartbounds = l64_getpartbounds,
483 	.op_loadpartinfo = l64_loadpartinfo,
484 	.op_getnumparts = l64_getnumparts,
485 	.op_makevirginlabel = l64_makevirginlabel
486 };
487 
488