xref: /freebsd-12.1/stand/common/disk.c (revision fffbc2b2)
1 /*-
2  * Copyright (c) 1998 Michael Smith <[email protected]>
3  * Copyright (c) 2012 Andrey V. Elsukov <[email protected]>
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 *
display_size(uint64_t size,u_int sectorsize)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
ptblread(void * d,void * buf,size_t blocks,uint64_t offset)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
ptable_print(void * arg,const char * pname,const struct ptable_entry * part)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
disk_print(struct disk_devdesc * dev,char * prefix,int verbose)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
disk_read(struct disk_devdesc * dev,void * buf,uint64_t offset,u_int blocks)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
disk_write(struct disk_devdesc * dev,void * buf,uint64_t offset,u_int blocks)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
disk_ioctl(struct disk_devdesc * dev,u_long cmd,void * data)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
disk_open(struct disk_devdesc * dev,uint64_t mediasize,u_int sectorsize)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 	if (sectorsize == 0) {
232 		DEBUG("unknown sector size");
233 		return (ENXIO);
234 	}
235 	rc = 0;
236 	od = (struct open_disk *)malloc(sizeof(struct open_disk));
237 	if (od == NULL) {
238 		DEBUG("no memory");
239 		return (ENOMEM);
240 	}
241 	dev->dd.d_opendata = od;
242 	od->entrysize = 0;
243 	od->mediasize = mediasize;
244 	od->sectorsize = sectorsize;
245 	/*
246 	 * While we are reading disk metadata, make sure we do it relative
247 	 * to the start of the disk
248 	 */
249 	memcpy(&partdev, dev, sizeof(partdev));
250 	partdev.d_offset = 0;
251 	partdev.d_slice = -1;
252 	partdev.d_partition = -1;
253 
254 	dev->d_offset = 0;
255 	table = NULL;
256 	slice = dev->d_slice;
257 	partition = dev->d_partition;
258 
259 	DEBUG("%s unit %d, slice %d, partition %d => %p",
260 	    disk_fmtdev(dev), dev->dd.d_unit, dev->d_slice, dev->d_partition, od);
261 
262 	/* Determine disk layout. */
263 	od->table = ptable_open(&partdev, mediasize / sectorsize, sectorsize,
264 	    ptblread);
265 	if (od->table == NULL) {
266 		DEBUG("Can't read partition table");
267 		rc = ENXIO;
268 		goto out;
269 	}
270 
271 	if (ptable_getsize(od->table, &mediasize) != 0) {
272 		rc = ENXIO;
273 		goto out;
274 	}
275 	od->mediasize = mediasize;
276 
277 	if (ptable_gettype(od->table) == PTABLE_BSD &&
278 	    partition >= 0) {
279 		/* It doesn't matter what value has d_slice */
280 		rc = ptable_getpart(od->table, &part, partition);
281 		if (rc == 0) {
282 			dev->d_offset = part.start;
283 			od->entrysize = part.end - part.start + 1;
284 		}
285 	} else if (ptable_gettype(od->table) == PTABLE_ISO9660) {
286 		dev->d_offset = 0;
287 		od->entrysize = mediasize;
288 	} else if (slice >= 0) {
289 		/* Try to get information about partition */
290 		if (slice == 0)
291 			rc = ptable_getbestpart(od->table, &part);
292 		else
293 			rc = ptable_getpart(od->table, &part, slice);
294 		if (rc != 0) /* Partition doesn't exist */
295 			goto out;
296 		dev->d_offset = part.start;
297 		od->entrysize = part.end - part.start + 1;
298 		slice = part.index;
299 		if (ptable_gettype(od->table) == PTABLE_GPT) {
300 			partition = 255;
301 			goto out; /* Nothing more to do */
302 		} else if (partition == 255) {
303 			/*
304 			 * When we try to open GPT partition, but partition
305 			 * table isn't GPT, reset d_partition value to -1
306 			 * and try to autodetect appropriate value.
307 			 */
308 			partition = -1;
309 		}
310 		/*
311 		 * If d_partition < 0 and we are looking at a BSD slice,
312 		 * then try to read BSD label, otherwise return the
313 		 * whole MBR slice.
314 		 */
315 		if (partition == -1 &&
316 		    part.type != PART_FREEBSD)
317 			goto out;
318 		/* Try to read BSD label */
319 		table = ptable_open(dev, part.end - part.start + 1,
320 		    od->sectorsize, ptblread);
321 		if (table == NULL) {
322 			DEBUG("Can't read BSD label");
323 			rc = ENXIO;
324 			goto out;
325 		}
326 		/*
327 		 * If slice contains BSD label and d_partition < 0, then
328 		 * assume the 'a' partition. Otherwise just return the
329 		 * whole MBR slice, because it can contain ZFS.
330 		 */
331 		if (partition < 0) {
332 			if (ptable_gettype(table) != PTABLE_BSD)
333 				goto out;
334 			partition = 0;
335 		}
336 		rc = ptable_getpart(table, &part, partition);
337 		if (rc != 0)
338 			goto out;
339 		dev->d_offset += part.start;
340 		od->entrysize = part.end - part.start + 1;
341 	}
342 out:
343 	if (table != NULL)
344 		ptable_close(table);
345 
346 	if (rc != 0) {
347 		if (od->table != NULL)
348 			ptable_close(od->table);
349 		free(od);
350 		DEBUG("%s could not open", disk_fmtdev(dev));
351 	} else {
352 		/* Save the slice and partition number to the dev */
353 		dev->d_slice = slice;
354 		dev->d_partition = partition;
355 		DEBUG("%s offset %lld => %p", disk_fmtdev(dev),
356 		    (long long)dev->d_offset, od);
357 	}
358 	return (rc);
359 }
360 
361 int
disk_close(struct disk_devdesc * dev)362 disk_close(struct disk_devdesc *dev)
363 {
364 	struct open_disk *od;
365 
366 	od = (struct open_disk *)dev->dd.d_opendata;
367 	DEBUG("%s closed => %p", disk_fmtdev(dev), od);
368 	ptable_close(od->table);
369 	free(od);
370 	return (0);
371 }
372 
373 char*
disk_fmtdev(struct disk_devdesc * dev)374 disk_fmtdev(struct disk_devdesc *dev)
375 {
376 	static char buf[128];
377 	char *cp;
378 
379 	cp = buf + sprintf(buf, "%s%d", dev->dd.d_dev->dv_name, dev->dd.d_unit);
380 	if (dev->d_slice >= 0) {
381 #ifdef LOADER_GPT_SUPPORT
382 		if (dev->d_partition == 255) {
383 			sprintf(cp, "p%d:", dev->d_slice);
384 			return (buf);
385 		} else
386 #endif
387 #ifdef LOADER_MBR_SUPPORT
388 			cp += sprintf(cp, "s%d", dev->d_slice);
389 #endif
390 	}
391 	if (dev->d_partition >= 0)
392 		cp += sprintf(cp, "%c", dev->d_partition + 'a');
393 	strcat(cp, ":");
394 	return (buf);
395 }
396 
397 int
disk_parsedev(struct disk_devdesc * dev,const char * devspec,const char ** path)398 disk_parsedev(struct disk_devdesc *dev, const char *devspec, const char **path)
399 {
400 	int unit, slice, partition;
401 	const char *np;
402 	char *cp;
403 
404 	np = devspec;
405 	unit = slice = partition = -1;
406 	if (*np != '\0' && *np != ':') {
407 		unit = strtol(np, &cp, 10);
408 		if (cp == np)
409 			return (EUNIT);
410 #ifdef LOADER_GPT_SUPPORT
411 		if (*cp == 'p') {
412 			np = cp + 1;
413 			slice = strtol(np, &cp, 10);
414 			if (np == cp)
415 				return (ESLICE);
416 			/* we don't support nested partitions on GPT */
417 			if (*cp != '\0' && *cp != ':')
418 				return (EINVAL);
419 			partition = 255;
420 		} else
421 #endif
422 #ifdef LOADER_MBR_SUPPORT
423 		if (*cp == 's') {
424 			np = cp + 1;
425 			slice = strtol(np, &cp, 10);
426 			if (np == cp)
427 				return (ESLICE);
428 		}
429 #endif
430 		if (*cp != '\0' && *cp != ':') {
431 			partition = *cp - 'a';
432 			if (partition < 0)
433 				return (EPART);
434 			cp++;
435 		}
436 	} else
437 		return (EINVAL);
438 
439 	if (*cp != '\0' && *cp != ':')
440 		return (EINVAL);
441 	dev->dd.d_unit = unit;
442 	dev->d_slice = slice;
443 	dev->d_partition = partition;
444 	if (path != NULL)
445 		*path = (*cp == '\0') ? cp: cp + 1;
446 	return (0);
447 }
448