xref: /freebsd/stand/common/disk.c (revision 0957b409)
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 DEBUG(fmt, args...)	printf("%s: " fmt "\n" , __func__ , ## args)
42 #else
43 # define DEBUG(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 = -1;
133 		if (disk_open(&dev, partsize, sectsize) == 0) {
134 			/*
135 			 * disk_open() for partition -1 on a bsd slice assumes
136 			 * you want the first bsd partition.  Reset things so
137 			 * that we're looking at the start of the raw slice.
138 			 */
139 			dev.d_partition = -1;
140 			dev.d_offset = part->start;
141 			table = ptable_open(&dev, partsize, sectsize, ptblread);
142 			if (table != NULL) {
143 				sprintf(line, "  %s%s", pa->prefix, pname);
144 				bsd.dev = pa->dev;
145 				bsd.prefix = line;
146 				bsd.verbose = pa->verbose;
147 				res = ptable_iterate(table, &bsd, ptable_print);
148 				ptable_close(table);
149 			}
150 			disk_close(&dev);
151 		}
152 	}
153 
154 	return (res);
155 }
156 
157 int
158 disk_print(struct disk_devdesc *dev, char *prefix, int verbose)
159 {
160 	struct open_disk *od;
161 	struct print_args pa;
162 
163 	/* Disk should be opened */
164 	od = (struct open_disk *)dev->dd.d_opendata;
165 	pa.dev = dev;
166 	pa.prefix = prefix;
167 	pa.verbose = verbose;
168 	return (ptable_iterate(od->table, &pa, ptable_print));
169 }
170 
171 int
172 disk_read(struct disk_devdesc *dev, void *buf, uint64_t offset, u_int blocks)
173 {
174 	struct open_disk *od;
175 	int ret;
176 
177 	od = (struct open_disk *)dev->dd.d_opendata;
178 	ret = dev->dd.d_dev->dv_strategy(dev, F_READ, dev->d_offset + offset,
179 	    blocks * od->sectorsize, buf, NULL);
180 
181 	return (ret);
182 }
183 
184 int
185 disk_write(struct disk_devdesc *dev, void *buf, uint64_t offset, u_int blocks)
186 {
187 	struct open_disk *od;
188 	int ret;
189 
190 	od = (struct open_disk *)dev->dd.d_opendata;
191 	ret = dev->dd.d_dev->dv_strategy(dev, F_WRITE, dev->d_offset + offset,
192 	    blocks * od->sectorsize, buf, NULL);
193 
194 	return (ret);
195 }
196 
197 int
198 disk_ioctl(struct disk_devdesc *dev, u_long cmd, void *data)
199 {
200 	struct open_disk *od = dev->dd.d_opendata;
201 
202 	if (od == NULL)
203 		return (ENOTTY);
204 
205 	switch (cmd) {
206 	case DIOCGSECTORSIZE:
207 		*(u_int *)data = od->sectorsize;
208 		break;
209 	case DIOCGMEDIASIZE:
210 		if (dev->d_offset == 0)
211 			*(uint64_t *)data = od->mediasize;
212 		else
213 			*(uint64_t *)data = od->entrysize * od->sectorsize;
214 		break;
215 	default:
216 		return (ENOTTY);
217 	}
218 
219 	return (0);
220 }
221 
222 int
223 disk_open(struct disk_devdesc *dev, uint64_t mediasize, u_int sectorsize)
224 {
225 	struct disk_devdesc partdev;
226 	struct open_disk *od;
227 	struct ptable *table;
228 	struct ptable_entry part;
229 	int rc, slice, partition;
230 
231 	rc = 0;
232 	od = (struct open_disk *)malloc(sizeof(struct open_disk));
233 	if (od == NULL) {
234 		DEBUG("no memory");
235 		return (ENOMEM);
236 	}
237 	dev->dd.d_opendata = od;
238 	od->entrysize = 0;
239 	od->mediasize = mediasize;
240 	od->sectorsize = sectorsize;
241 	/*
242 	 * While we are reading disk metadata, make sure we do it relative
243 	 * to the start of the disk
244 	 */
245 	memcpy(&partdev, dev, sizeof(partdev));
246 	partdev.d_offset = 0;
247 	partdev.d_slice = -1;
248 	partdev.d_partition = -1;
249 
250 	dev->d_offset = 0;
251 	table = NULL;
252 	slice = dev->d_slice;
253 	partition = dev->d_partition;
254 
255 	DEBUG("%s unit %d, slice %d, partition %d => %p",
256 	    disk_fmtdev(dev), dev->dd.d_unit, dev->d_slice, dev->d_partition, od);
257 
258 	/* Determine disk layout. */
259 	od->table = ptable_open(&partdev, mediasize / sectorsize, sectorsize,
260 	    ptblread);
261 	if (od->table == NULL) {
262 		DEBUG("Can't read partition table");
263 		rc = ENXIO;
264 		goto out;
265 	}
266 
267 	if (ptable_getsize(od->table, &mediasize) != 0) {
268 		rc = ENXIO;
269 		goto out;
270 	}
271 	od->mediasize = mediasize;
272 
273 	if (ptable_gettype(od->table) == PTABLE_BSD &&
274 	    partition >= 0) {
275 		/* It doesn't matter what value has d_slice */
276 		rc = ptable_getpart(od->table, &part, partition);
277 		if (rc == 0) {
278 			dev->d_offset = part.start;
279 			od->entrysize = part.end - part.start + 1;
280 		}
281 	} else if (ptable_gettype(od->table) == PTABLE_ISO9660) {
282 		dev->d_offset = 0;
283 		od->entrysize = mediasize;
284 	} else if (slice >= 0) {
285 		/* Try to get information about partition */
286 		if (slice == 0)
287 			rc = ptable_getbestpart(od->table, &part);
288 		else
289 			rc = ptable_getpart(od->table, &part, slice);
290 		if (rc != 0) /* Partition doesn't exist */
291 			goto out;
292 		dev->d_offset = part.start;
293 		od->entrysize = part.end - part.start + 1;
294 		slice = part.index;
295 		if (ptable_gettype(od->table) == PTABLE_GPT) {
296 			partition = 255;
297 			goto out; /* Nothing more to do */
298 		} else if (partition == 255) {
299 			/*
300 			 * When we try to open GPT partition, but partition
301 			 * table isn't GPT, reset d_partition value to -1
302 			 * and try to autodetect appropriate value.
303 			 */
304 			partition = -1;
305 		}
306 		/*
307 		 * If d_partition < 0 and we are looking at a BSD slice,
308 		 * then try to read BSD label, otherwise return the
309 		 * whole MBR slice.
310 		 */
311 		if (partition == -1 &&
312 		    part.type != PART_FREEBSD)
313 			goto out;
314 		/* Try to read BSD label */
315 		table = ptable_open(dev, part.end - part.start + 1,
316 		    od->sectorsize, ptblread);
317 		if (table == NULL) {
318 			DEBUG("Can't read BSD label");
319 			rc = ENXIO;
320 			goto out;
321 		}
322 		/*
323 		 * If slice contains BSD label and d_partition < 0, then
324 		 * assume the 'a' partition. Otherwise just return the
325 		 * whole MBR slice, because it can contain ZFS.
326 		 */
327 		if (partition < 0) {
328 			if (ptable_gettype(table) != PTABLE_BSD)
329 				goto out;
330 			partition = 0;
331 		}
332 		rc = ptable_getpart(table, &part, partition);
333 		if (rc != 0)
334 			goto out;
335 		dev->d_offset += part.start;
336 		od->entrysize = part.end - part.start + 1;
337 	}
338 out:
339 	if (table != NULL)
340 		ptable_close(table);
341 
342 	if (rc != 0) {
343 		if (od->table != NULL)
344 			ptable_close(od->table);
345 		free(od);
346 		DEBUG("%s could not open", disk_fmtdev(dev));
347 	} else {
348 		/* Save the slice and partition number to the dev */
349 		dev->d_slice = slice;
350 		dev->d_partition = partition;
351 		DEBUG("%s offset %lld => %p", disk_fmtdev(dev),
352 		    (long long)dev->d_offset, od);
353 	}
354 	return (rc);
355 }
356 
357 int
358 disk_close(struct disk_devdesc *dev)
359 {
360 	struct open_disk *od;
361 
362 	od = (struct open_disk *)dev->dd.d_opendata;
363 	DEBUG("%s closed => %p", disk_fmtdev(dev), od);
364 	ptable_close(od->table);
365 	free(od);
366 	return (0);
367 }
368 
369 char*
370 disk_fmtdev(struct disk_devdesc *dev)
371 {
372 	static char buf[128];
373 	char *cp;
374 
375 	cp = buf + sprintf(buf, "%s%d", dev->dd.d_dev->dv_name, dev->dd.d_unit);
376 	if (dev->d_slice >= 0) {
377 #ifdef LOADER_GPT_SUPPORT
378 		if (dev->d_partition == 255) {
379 			sprintf(cp, "p%d:", dev->d_slice);
380 			return (buf);
381 		} else
382 #endif
383 #ifdef LOADER_MBR_SUPPORT
384 			cp += sprintf(cp, "s%d", dev->d_slice);
385 #endif
386 	}
387 	if (dev->d_partition >= 0)
388 		cp += sprintf(cp, "%c", dev->d_partition + 'a');
389 	strcat(cp, ":");
390 	return (buf);
391 }
392 
393 int
394 disk_parsedev(struct disk_devdesc *dev, const char *devspec, const char **path)
395 {
396 	int unit, slice, partition;
397 	const char *np;
398 	char *cp;
399 
400 	np = devspec;
401 	unit = slice = partition = -1;
402 	if (*np != '\0' && *np != ':') {
403 		unit = strtol(np, &cp, 10);
404 		if (cp == np)
405 			return (EUNIT);
406 #ifdef LOADER_GPT_SUPPORT
407 		if (*cp == 'p') {
408 			np = cp + 1;
409 			slice = strtol(np, &cp, 10);
410 			if (np == cp)
411 				return (ESLICE);
412 			/* we don't support nested partitions on GPT */
413 			if (*cp != '\0' && *cp != ':')
414 				return (EINVAL);
415 			partition = 255;
416 		} else
417 #endif
418 #ifdef LOADER_MBR_SUPPORT
419 		if (*cp == 's') {
420 			np = cp + 1;
421 			slice = strtol(np, &cp, 10);
422 			if (np == cp)
423 				return (ESLICE);
424 		}
425 #endif
426 		if (*cp != '\0' && *cp != ':') {
427 			partition = *cp - 'a';
428 			if (partition < 0)
429 				return (EPART);
430 			cp++;
431 		}
432 	} else
433 		return (EINVAL);
434 
435 	if (*cp != '\0' && *cp != ':')
436 		return (EINVAL);
437 	dev->dd.d_unit = unit;
438 	dev->d_slice = slice;
439 	dev->d_partition = partition;
440 	if (path != NULL)
441 		*path = (*cp == '\0') ? cp: cp + 1;
442 	return (0);
443 }
444