xref: /freebsd/stand/common/disk.c (revision daceb336172a6b0572de864b97e70b28451ca636)
1 /*-
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * Copyright (c) 2012 Andrey V. Elsukov <ae@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/disk.h>
32 #include <sys/queue.h>
33 #include <stand.h>
34 #include <stdarg.h>
35 #include <bootstrap.h>
36 #include <part.h>
37 
38 #include "disk.h"
39 
40 #ifdef DISK_DEBUG
41 # define DPRINTF(fmt, args...)	printf("%s: " fmt "\n" , __func__ , ## args)
42 #else
43 # define DPRINTF(fmt, args...)
44 #endif
45 
46 struct open_disk {
47 	struct ptable		*table;
48 	uint64_t		mediasize;
49 	uint64_t		entrysize;
50 	u_int			sectorsize;
51 };
52 
53 struct print_args {
54 	struct disk_devdesc	*dev;
55 	const char		*prefix;
56 	int			verbose;
57 };
58 
59 /* Convert size to a human-readable number. */
60 static char *
61 display_size(uint64_t size, u_int sectorsize)
62 {
63 	static char buf[80];
64 	char unit;
65 
66 	size = size * sectorsize / 1024;
67 	unit = 'K';
68 	if (size >= 10485760000LL) {
69 		size /= 1073741824;
70 		unit = 'T';
71 	} else if (size >= 10240000) {
72 		size /= 1048576;
73 		unit = 'G';
74 	} else if (size >= 10000) {
75 		size /= 1024;
76 		unit = 'M';
77 	}
78 	sprintf(buf, "%4ld%cB", (long)size, unit);
79 	return (buf);
80 }
81 
82 int
83 ptblread(void *d, void *buf, size_t blocks, uint64_t offset)
84 {
85 	struct disk_devdesc *dev;
86 	struct open_disk *od;
87 
88 	dev = (struct disk_devdesc *)d;
89 	od = (struct open_disk *)dev->dd.d_opendata;
90 
91 	/*
92 	 * The strategy function assumes the offset is in units of 512 byte
93 	 * sectors. For larger sector sizes, we need to adjust the offset to
94 	 * match the actual sector size.
95 	 */
96 	offset *= (od->sectorsize / 512);
97 	/*
98 	 * As the GPT backup partition is located at the end of the disk,
99 	 * to avoid reading past disk end, flag bcache not to use RA.
100 	 */
101 	return (dev->dd.d_dev->dv_strategy(dev, F_READ | F_NORA, offset,
102 	    blocks * od->sectorsize, (char *)buf, NULL));
103 }
104 
105 static int
106 ptable_print(void *arg, const char *pname, const struct ptable_entry *part)
107 {
108 	struct disk_devdesc dev;
109 	struct print_args *pa, bsd;
110 	struct open_disk *od;
111 	struct ptable *table;
112 	char line[80];
113 	int res;
114 	u_int sectsize;
115 	uint64_t partsize;
116 
117 	pa = (struct print_args *)arg;
118 	od = (struct open_disk *)pa->dev->dd.d_opendata;
119 	sectsize = od->sectorsize;
120 	partsize = part->end - part->start + 1;
121 	sprintf(line, "  %s%s: %s\t%s\n", pa->prefix, pname,
122 	    parttype2str(part->type),
123 	    pa->verbose ? display_size(partsize, sectsize) : "");
124 	if (pager_output(line))
125 		return 1;
126 	res = 0;
127 	if (part->type == PART_FREEBSD) {
128 		/* Open slice with BSD label */
129 		dev.dd.d_dev = pa->dev->dd.d_dev;
130 		dev.dd.d_unit = pa->dev->dd.d_unit;
131 		dev.d_slice = part->index;
132 		dev.d_partition = D_PARTNONE;
133 		if (disk_open(&dev, partsize, sectsize) == 0) {
134 			table = ptable_open(&dev, partsize, sectsize, ptblread);
135 			if (table != NULL) {
136 				sprintf(line, "  %s%s", pa->prefix, pname);
137 				bsd.dev = pa->dev;
138 				bsd.prefix = line;
139 				bsd.verbose = pa->verbose;
140 				res = ptable_iterate(table, &bsd, ptable_print);
141 				ptable_close(table);
142 			}
143 			disk_close(&dev);
144 		}
145 	}
146 
147 	return (res);
148 }
149 
150 int
151 disk_print(struct disk_devdesc *dev, char *prefix, int verbose)
152 {
153 	struct open_disk *od;
154 	struct print_args pa;
155 
156 	/* Disk should be opened */
157 	od = (struct open_disk *)dev->dd.d_opendata;
158 	pa.dev = dev;
159 	pa.prefix = prefix;
160 	pa.verbose = verbose;
161 	return (ptable_iterate(od->table, &pa, ptable_print));
162 }
163 
164 int
165 disk_read(struct disk_devdesc *dev, void *buf, uint64_t offset, u_int blocks)
166 {
167 	struct open_disk *od;
168 	int ret;
169 
170 	od = (struct open_disk *)dev->dd.d_opendata;
171 	ret = dev->dd.d_dev->dv_strategy(dev, F_READ, dev->d_offset + offset,
172 	    blocks * od->sectorsize, buf, NULL);
173 
174 	return (ret);
175 }
176 
177 int
178 disk_write(struct disk_devdesc *dev, void *buf, uint64_t offset, u_int blocks)
179 {
180 	struct open_disk *od;
181 	int ret;
182 
183 	od = (struct open_disk *)dev->dd.d_opendata;
184 	ret = dev->dd.d_dev->dv_strategy(dev, F_WRITE, dev->d_offset + offset,
185 	    blocks * od->sectorsize, buf, NULL);
186 
187 	return (ret);
188 }
189 
190 int
191 disk_ioctl(struct disk_devdesc *dev, u_long cmd, void *data)
192 {
193 	struct open_disk *od = dev->dd.d_opendata;
194 
195 	if (od == NULL)
196 		return (ENOTTY);
197 
198 	switch (cmd) {
199 	case DIOCGSECTORSIZE:
200 		*(u_int *)data = od->sectorsize;
201 		break;
202 	case DIOCGMEDIASIZE:
203 		if (dev->d_offset == 0)
204 			*(uint64_t *)data = od->mediasize;
205 		else
206 			*(uint64_t *)data = od->entrysize * od->sectorsize;
207 		break;
208 	default:
209 		return (ENOTTY);
210 	}
211 
212 	return (0);
213 }
214 
215 int
216 disk_open(struct disk_devdesc *dev, uint64_t mediasize, u_int sectorsize)
217 {
218 	struct disk_devdesc partdev;
219 	struct open_disk *od;
220 	struct ptable *table;
221 	struct ptable_entry part;
222 	int rc, slice, partition;
223 
224 	if (sectorsize == 0) {
225 		DPRINTF("unknown sector size");
226 		return (ENXIO);
227 	}
228 	rc = 0;
229 	od = (struct open_disk *)malloc(sizeof(struct open_disk));
230 	if (od == NULL) {
231 		DPRINTF("no memory");
232 		return (ENOMEM);
233 	}
234 	dev->dd.d_opendata = od;
235 	od->entrysize = 0;
236 	od->mediasize = mediasize;
237 	od->sectorsize = sectorsize;
238 	/*
239 	 * While we are reading disk metadata, make sure we do it relative
240 	 * to the start of the disk
241 	 */
242 	memcpy(&partdev, dev, sizeof(partdev));
243 	partdev.d_offset = 0;
244 	partdev.d_slice = D_SLICENONE;
245 	partdev.d_partition = D_PARTNONE;
246 
247 	dev->d_offset = 0;
248 	table = NULL;
249 	slice = dev->d_slice;
250 	partition = dev->d_partition;
251 
252 	DPRINTF("%s unit %d, slice %d, partition %d => %p",
253 	    disk_fmtdev(dev), dev->dd.d_unit, dev->d_slice, dev->d_partition, od);
254 
255 	/* Determine disk layout. */
256 	od->table = ptable_open(&partdev, mediasize / sectorsize, sectorsize,
257 	    ptblread);
258 	if (od->table == NULL) {
259 		DPRINTF("Can't read partition table");
260 		rc = ENXIO;
261 		goto out;
262 	}
263 
264 	if (ptable_getsize(od->table, &mediasize) != 0) {
265 		rc = ENXIO;
266 		goto out;
267 	}
268 	od->mediasize = mediasize;
269 
270 	if (ptable_gettype(od->table) == PTABLE_BSD &&
271 	    partition >= 0) {
272 		/* It doesn't matter what value has d_slice */
273 		rc = ptable_getpart(od->table, &part, partition);
274 		if (rc == 0) {
275 			dev->d_offset = part.start;
276 			od->entrysize = part.end - part.start + 1;
277 		}
278 	} else if (ptable_gettype(od->table) == PTABLE_ISO9660) {
279 		dev->d_offset = 0;
280 		od->entrysize = mediasize;
281 	} else if (slice >= 0) {
282 		/* Try to get information about partition */
283 		if (slice == 0)
284 			rc = ptable_getbestpart(od->table, &part);
285 		else
286 			rc = ptable_getpart(od->table, &part, slice);
287 		if (rc != 0) /* Partition doesn't exist */
288 			goto out;
289 		dev->d_offset = part.start;
290 		od->entrysize = part.end - part.start + 1;
291 		slice = part.index;
292 		if (ptable_gettype(od->table) == PTABLE_GPT) {
293 			partition = D_PARTISGPT;
294 			goto out; /* Nothing more to do */
295 		} else if (partition == D_PARTISGPT) {
296 			/*
297 			 * When we try to open GPT partition, but partition
298 			 * table isn't GPT, reset d_partition value to -1
299 			 * and try to autodetect appropriate value.
300 			 */
301 			partition = -1;
302 		}
303 		/*
304 		 * If d_partition < 0 and we are looking at a BSD slice,
305 		 * then try to read BSD label, otherwise return the
306 		 * whole MBR slice.
307 		 */
308 		if (partition == -1 &&
309 		    part.type != PART_FREEBSD)
310 			goto out;
311 		/* Try to read BSD label */
312 		table = ptable_open(dev, part.end - part.start + 1,
313 		    od->sectorsize, ptblread);
314 		if (table == NULL) {
315 			DPRINTF("Can't read BSD label");
316 			rc = ENXIO;
317 			goto out;
318 		}
319 		/*
320 		 * If slice contains BSD label and d_partition < 0, then
321 		 * assume the 'a' partition. Otherwise just return the
322 		 * whole MBR slice, because it can contain ZFS.
323 		 */
324 		if (partition < 0) {
325 			if (ptable_gettype(table) != PTABLE_BSD)
326 				goto out;
327 			partition = 0;
328 		}
329 		rc = ptable_getpart(table, &part, partition);
330 		if (rc != 0)
331 			goto out;
332 		dev->d_offset += part.start;
333 		od->entrysize = part.end - part.start + 1;
334 	}
335 out:
336 	if (table != NULL)
337 		ptable_close(table);
338 
339 	if (rc != 0) {
340 		if (od->table != NULL)
341 			ptable_close(od->table);
342 		free(od);
343 		DPRINTF("%s could not open", disk_fmtdev(dev));
344 	} else {
345 		/* Save the slice and partition number to the dev */
346 		dev->d_slice = slice;
347 		dev->d_partition = partition;
348 		DPRINTF("%s offset %lld => %p", disk_fmtdev(dev),
349 		    (long long)dev->d_offset, od);
350 	}
351 	return (rc);
352 }
353 
354 int
355 disk_close(struct disk_devdesc *dev)
356 {
357 	struct open_disk *od;
358 
359 	od = (struct open_disk *)dev->dd.d_opendata;
360 	DPRINTF("%s closed => %p", disk_fmtdev(dev), od);
361 	ptable_close(od->table);
362 	free(od);
363 	return (0);
364 }
365 
366 char*
367 disk_fmtdev(struct disk_devdesc *dev)
368 {
369 	static char buf[128];
370 	char *cp;
371 
372 	cp = buf + sprintf(buf, "%s%d", dev->dd.d_dev->dv_name, dev->dd.d_unit);
373 	if (dev->d_slice > D_SLICENONE) {
374 #ifdef LOADER_GPT_SUPPORT
375 		if (dev->d_partition == D_PARTISGPT) {
376 			sprintf(cp, "p%d:", dev->d_slice);
377 			return (buf);
378 		} else
379 #endif
380 #ifdef LOADER_MBR_SUPPORT
381 			cp += sprintf(cp, "s%d", dev->d_slice);
382 #endif
383 	}
384 	if (dev->d_partition > D_PARTNONE)
385 		cp += sprintf(cp, "%c", dev->d_partition + 'a');
386 	strcat(cp, ":");
387 	return (buf);
388 }
389 
390 int
391 disk_parsedev(struct disk_devdesc *dev, const char *devspec, const char **path)
392 {
393 	int unit, slice, partition;
394 	const char *np;
395 	char *cp;
396 
397 	np = devspec;
398 	unit = -1;
399 	/*
400 	 * If there is path/file info after the device info, then any missing
401 	 * slice or partition info should be considered a request to search for
402 	 * an appropriate partition.  Otherwise we want to open the raw device
403 	 * itself and not try to fill in missing info by searching.
404 	 */
405 	if ((cp = strchr(np, ':')) != NULL && cp[1] != '\0') {
406 		slice = D_SLICEWILD;
407 		partition = D_PARTWILD;
408 	} else {
409 		slice = D_SLICENONE;
410 		partition = D_PARTNONE;
411 	}
412 
413 	if (*np != '\0' && *np != ':') {
414 		unit = strtol(np, &cp, 10);
415 		if (cp == np)
416 			return (EUNIT);
417 #ifdef LOADER_GPT_SUPPORT
418 		if (*cp == 'p') {
419 			np = cp + 1;
420 			slice = strtol(np, &cp, 10);
421 			if (np == cp)
422 				return (ESLICE);
423 			/* we don't support nested partitions on GPT */
424 			if (*cp != '\0' && *cp != ':')
425 				return (EINVAL);
426 			partition = D_PARTISGPT;
427 		} else
428 #endif
429 #ifdef LOADER_MBR_SUPPORT
430 		if (*cp == 's') {
431 			np = cp + 1;
432 			slice = strtol(np, &cp, 10);
433 			if (np == cp)
434 				return (ESLICE);
435 		}
436 #endif
437 		if (*cp != '\0' && *cp != ':') {
438 			partition = *cp - 'a';
439 			if (partition < 0)
440 				return (EPART);
441 			cp++;
442 		}
443 	} else
444 		return (EINVAL);
445 
446 	if (*cp != '\0' && *cp != ':')
447 		return (EINVAL);
448 	dev->dd.d_unit = unit;
449 	dev->d_slice = slice;
450 	dev->d_partition = partition;
451 	if (path != NULL)
452 		*path = (*cp == '\0') ? cp: cp + 1;
453 	return (0);
454 }
455