xref: /dragonfly/sys/kern/subr_diskgpt.c (revision 67640b13)
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 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/conf.h>
38 #include <sys/endian.h>
39 #include <sys/diskslice.h>
40 #include <sys/diskmbr.h>
41 #include <sys/disk.h>
42 #include <sys/buf.h>
43 #include <sys/malloc.h>
44 #include <sys/syslog.h>
45 #include <sys/bus.h>
46 #include <sys/device.h>
47 #include <sys/gpt.h>
48 
49 static void gpt_setslice(const char *sname, struct disk_info *info,
50 			 struct diskslice *sp, struct gpt_ent *sent);
51 
52 /*
53  * Handle GPT on raw disk.  Note that GPTs are not recursive.  The MBR is
54  * ignored once a GPT has been detected.
55  *
56  * GPTs always start at block #1, regardless of how the MBR has been set up.
57  * In fact, the MBR's starting block might be pointing to the boot partition
58  * in the GPT rather then to the start of the GPT.
59  *
60  * This routine is called from mbrinit() when a GPT has been detected.
61  */
62 int
63 gptinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp)
64 {
65 	struct buf *bp1 = NULL;
66 	struct buf *bp2 = NULL;
67 	struct gpt_hdr *gpt;
68 	struct gpt_ent *ent;
69 	struct diskslice *sp;
70 	struct diskslices *ssp;
71 	cdev_t wdev;
72 	int error;
73 	uint32_t len;
74 	uint32_t entries;
75 	uint32_t entsz;
76 	uint32_t crc;
77 	uint32_t table_lba;
78 	uint32_t table_blocks;
79 	int i = 0, j;
80 	const char *dname;
81 
82 	/*
83 	 * The GPT starts in sector 1.
84 	 */
85 	wdev = dev;
86 	dname = dev_dname(wdev);
87 	bp1 = geteblk((int)info->d_media_blksize);
88 	bp1->b_bio1.bio_offset = info->d_media_blksize;
89 	bp1->b_bio1.bio_done = biodone_sync;
90 	bp1->b_bio1.bio_flags |= BIO_SYNC;
91 	bp1->b_bcount = info->d_media_blksize;
92 	bp1->b_cmd = BUF_CMD_READ;
93 	bp1->b_flags |= B_FAILONDIS;
94 	dev_dstrategy(wdev, &bp1->b_bio1);
95 	if (biowait(&bp1->b_bio1, "gptrd") != 0) {
96 		kprintf("%s: reading GPT @ block 1: error %d\n",
97 			dname, bp1->b_error);
98 		error = EIO;
99 		goto done;
100 	}
101 
102 	/*
103 	 * Header sanity check
104 	 */
105 	gpt = (void *)bp1->b_data;
106 	len = le32toh(gpt->hdr_size);
107 	if (len < GPT_MIN_HDR_SIZE || len > info->d_media_blksize) {
108 		kprintf("%s: Illegal GPT header size %d\n", dname, len);
109 		error = EINVAL;
110 		goto done;
111 	}
112 
113 	crc = le32toh(gpt->hdr_crc_self);
114 	gpt->hdr_crc_self = 0;
115 	if (crc32(gpt, len) != crc) {
116 		kprintf("%s: GPT CRC32 did not match\n", dname);
117 		error = EINVAL;
118 		goto done;
119 	}
120 
121 	/*
122 	 * Validate the partition table and its location, then read it
123 	 * into a buffer.
124 	 */
125 	entries = le32toh(gpt->hdr_entries);
126 	entsz = le32toh(gpt->hdr_entsz);
127 	table_lba = le32toh(gpt->hdr_lba_table);
128 	table_blocks = (entries * entsz + info->d_media_blksize - 1) /
129 		       info->d_media_blksize;
130 	if (entries < 1 || entries > 128 ||
131 	    entsz < 128 || (entsz & 7) || entsz > MAXBSIZE / entries ||
132 	    table_lba < 2 || table_lba + table_blocks > info->d_media_blocks) {
133 		kprintf("%s: GPT partition table is out of bounds\n", dname);
134 		error = EINVAL;
135 		goto done;
136 	}
137 
138 	/*
139 	 * XXX subject to device dma size limitations
140 	 */
141 	bp2 = geteblk((int)(table_blocks * info->d_media_blksize));
142 	bp2->b_bio1.bio_offset = (off_t)table_lba * info->d_media_blksize;
143 	bp2->b_bio1.bio_done = biodone_sync;
144 	bp2->b_bio1.bio_flags |= BIO_SYNC;
145 	bp2->b_bcount = table_blocks * info->d_media_blksize;
146 	bp2->b_cmd = BUF_CMD_READ;
147 	bp2->b_flags |= B_FAILONDIS;
148 	dev_dstrategy(wdev, &bp2->b_bio1);
149 	if (biowait(&bp2->b_bio1, "gptrd") != 0) {
150 		kprintf("%s: reading GPT partition table @ %lld: error %d\n",
151 			dname,
152 			(long long)bp2->b_bio1.bio_offset,
153 			bp2->b_error);
154 		error = EIO;
155 		goto done;
156 	}
157 
158 	/*
159 	 * We are passed a pointer to a minimal slices struct.  Replace
160 	 * it with a maximal one (128 slices + special slices).  Well,
161 	 * really there is only one special slice (the WHOLE_DISK_SLICE)
162 	 * since we use the compatibility slice for s0, but don't quibble.
163 	 *
164 	 */
165 	kfree(*sspp, M_DEVBUF);
166 	ssp = *sspp = dsmakeslicestruct(BASE_SLICE+128, info);
167 
168 	/*
169 	 * Create a slice for each partition.
170 	 */
171 	for (i = 0; i < (int)entries && i < 128; ++i) {
172 		struct gpt_ent sent;
173 		char partname[2];
174 		char *sname;
175 
176 		ent = (void *)((char *)bp2->b_data + i * entsz);
177 		le_uuid_dec(&ent->ent_type, &sent.ent_type);
178 		le_uuid_dec(&ent->ent_uuid, &sent.ent_uuid);
179 		sent.ent_lba_start = le64toh(ent->ent_lba_start);
180 		sent.ent_lba_end = le64toh(ent->ent_lba_end);
181 		sent.ent_attr = le64toh(ent->ent_attr);
182 
183 		for (j = 0; j < NELEM(ent->ent_name); ++j)
184 			sent.ent_name[j] = le16toh(ent->ent_name[j]);
185 
186 		/*
187 		 * The COMPATIBILITY_SLICE is actually slice 0 (s0).  This
188 		 * is a bit weird becaue the whole-disk slice is #1, so
189 		 * slice 1 (s1) starts at BASE_SLICE.
190 		 */
191 		if (i == 0)
192 			sp = &ssp->dss_slices[COMPATIBILITY_SLICE];
193 		else
194 			sp = &ssp->dss_slices[BASE_SLICE+i-1];
195 		sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE,
196 			       WHOLE_SLICE_PART, partname);
197 
198 		if (kuuid_is_nil(&sent.ent_type))
199 			continue;
200 
201 		if (sent.ent_lba_start < table_lba + table_blocks ||
202 		    sent.ent_lba_end >= info->d_media_blocks ||
203 		    sent.ent_lba_start >= sent.ent_lba_end) {
204 			kprintf("%s part %d: unavailable, bad start or "
205 				"ending lba\n",
206 				sname, i);
207 		} else {
208 			gpt_setslice(sname, info, sp, &sent);
209 		}
210 	}
211 	ssp->dss_nslices = BASE_SLICE + i;
212 
213 	error = 0;
214 done:
215 	if (bp1) {
216 		bp1->b_flags |= B_INVAL | B_AGE;
217 		brelse(bp1);
218 	}
219 	if (bp2) {
220 		bp2->b_flags |= B_INVAL | B_AGE;
221 		brelse(bp2);
222 	}
223 	if (error == EINVAL)
224 		error = 0;
225 	return (error);
226 }
227 
228 static
229 void
230 gpt_setslice(const char *sname, struct disk_info *info, struct diskslice *sp,
231 	     struct gpt_ent *sent)
232 {
233 	sp->ds_offset = sent->ent_lba_start;
234 	sp->ds_size   = sent->ent_lba_end + 1 - sent->ent_lba_start;
235 	sp->ds_type   = 1;	/* XXX */
236 	sp->ds_type_uuid = sent->ent_type;
237 	sp->ds_stor_uuid = sent->ent_uuid;
238 	sp->ds_reserved = 0;	/* no reserved sectors */
239 }
240 
241