sys/kern/subr_diskgpt.c

   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_diskgpt.c,v 1.4 2007/07/20 17:21:51 dillon Exp $
  35  */
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/conf.h>
  40 #include <sys/endian.h>
  41 #include <sys/diskslice.h>
  42 #include <sys/diskmbr.h>
  43 #include <sys/disk.h>
  44 #include <sys/buf.h>
  45 #include <sys/malloc.h>
  46 #include <sys/syslog.h>
  47 #include <sys/bus.h>
  48 #include <sys/device.h>
  49 #include <sys/gpt.h>
  50
  51 #define arysize(ary)    (sizeof(ary)/sizeof((ary)[0]))
  52
  53 static void gpt_setslice(const char *sname, struct disk_info *info,
  54                          struct diskslice *sp, struct gpt_ent *sent);
  55
  56 /*
  57  * Handle GPT on raw disk.  Note that GPTs are not recursive.  The MBR is
  58  * ignored once a GPT has been detected.
  59  *
  60  * GPTs always start at block #1, regardless of how the MBR has been set up.
  61  * In fact, the MBR's starting block might be pointing to the boot partition
  62  * in the GPT rather then to the start of the GPT.
  63  *
  64  * This routine is called from mbrinit() when a GPT has been detected.
  65  */
  66 int
  67 gptinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp)
  68 {
  69         struct buf *bp1 = NULL;
  70         struct buf *bp2 = NULL;
  71         struct gpt_hdr *gpt;
  72         struct gpt_ent *ent;
  73         struct diskslice *sp;
  74         struct diskslices *ssp;
  75         cdev_t wdev;
  76         int error;
  77         uint32_t len;
  78         uint32_t entries;
  79         uint32_t entsz;
  80         uint32_t crc;
  81         uint32_t table_lba;
  82         uint32_t table_blocks;
  83         int i = 0, j;
  84         const char *dname;
  85
  86         /*
  87          * The GPT starts in sector 1.
  88          */
  89         wdev = dkmodpart(dkmodslice(dev, WHOLE_DISK_SLICE), WHOLE_SLICE_PART);
  90         dname = dev_dname(wdev);
  91         bp1 = geteblk((int)info->d_media_blksize);
  92         bp1->b_bio1.bio_offset = info->d_media_blksize;
  93         bp1->b_bcount = info->d_media_blksize;
  94         bp1->b_cmd = BUF_CMD_READ;
  95         dev_dstrategy(wdev, &bp1->b_bio1);
  96         if (biowait(bp1) != 0) {
  97                 kprintf("%s: reading GPT @ block 1: error %d\n",
  98                         dname, bp1->b_error);
  99                 error = EIO;
 100                 goto done;
 101         }
 102
 103         /*
 104          * Header sanity check
 105          */
 106         gpt = (void *)bp1->b_data;
 107         len = le32toh(gpt->hdr_size);
 108         if (len < GPT_MIN_HDR_SIZE || len > info->d_media_blksize) {
 109                 kprintf("%s: Illegal GPT header size %d\n", dname, len);
 110                 error = EINVAL;
 111                 goto done;
 112         }
 113
 114         crc = le32toh(gpt->hdr_crc_self);
 115         gpt->hdr_crc_self = 0;
 116         if (crc32(gpt, len) != crc) {
 117                 kprintf("%s: GPT CRC32 did not match\n", dname);
 118                 error = EINVAL;
 119                 goto done;
 120         }
 121
 122         /*
 123          * Validate the partition table and its location, then read it
 124          * into a buffer.
 125          */
 126         entries = le32toh(gpt->hdr_entries);
 127         entsz = le32toh(gpt->hdr_entsz);
 128         table_lba = le32toh(gpt->hdr_lba_table);
 129         table_blocks = (entries * entsz + info->d_media_blksize - 1) /
 130                        info->d_media_blksize;
 131         if (entries < 1 || entries > 128 ||
 132             entsz < 128 || (entsz & 7) || entsz > MAXBSIZE / entries ||
 133             table_lba < 2 || table_lba + table_blocks > info->d_media_blocks) {
 134                 kprintf("%s: GPT partition table is out of bounds\n", dname);
 135                 error = EINVAL;
 136                 goto done;
 137         }
 138
 139         /*
 140          * XXX subject to device dma size limitations
 141          */
 142         bp2 = geteblk((int)(table_blocks * info->d_media_blksize));
 143         bp2->b_bio1.bio_offset = (off_t)table_lba * info->d_media_blksize;
 144         bp2->b_bcount = table_blocks * info->d_media_blksize;
 145         bp2->b_cmd = BUF_CMD_READ;
 146         dev_dstrategy(wdev, &bp2->b_bio1);
 147         if (biowait(bp2) != 0) {
 148                 kprintf("%s: reading GPT partition table @ %lld: error %d\n",
 149                         dname, bp2->b_bio1.bio_offset, bp2->b_error);
 150                 error = EIO;
 151                 goto done;
 152         }
 153
 154         /*
 155          * We are passed a pointer to a minimal slices struct.  Replace
 156          * it with a maximal one (128 slices + special slices).  Well,
 157          * really there is only one special slice (the WHOLE_DISK_SLICE)
 158          * since we use the compatibility slice for s0, but don't quibble.
 159          *
 160          */
 161         kfree(*sspp, M_DEVBUF);
 162         ssp = *sspp = dsmakeslicestruct(BASE_SLICE+128, info);
 163
 164         /*
 165          * Create a slice for each partition.
 166          */
 167         for (i = 0; i < (int)entries && i < 128; ++i) {
 168                 struct gpt_ent sent;
 169                 char partname[2];
 170                 char *sname;
 171
 172                 ent = (void *)((char *)bp2->b_data + i * entsz);
 173                 le_uuid_dec(&ent->ent_type, &sent.ent_type);
 174                 le_uuid_dec(&ent->ent_uuid, &sent.ent_uuid);
 175                 sent.ent_lba_start = le64toh(ent->ent_lba_start);
 176                 sent.ent_lba_end = le64toh(ent->ent_lba_end);
 177                 sent.ent_attr = le64toh(ent->ent_attr);
 178
 179                 for (j = 0; j < arysize(ent->ent_name); ++j)
 180                         sent.ent_name[j] = le16toh(ent->ent_name[j]);
 181
 182                 /*
 183                  * The COMPATIBILITY_SLICE is actually slice 0 (s0).  This
 184                  * is a bit weird becaue the whole-disk slice is #1, so
 185                  * slice 1 (s1) starts at BASE_SLICE.
 186                  */
 187                 if (i == 0)
 188                         sp = &ssp->dss_slices[COMPATIBILITY_SLICE];
 189                 else
 190                         sp = &ssp->dss_slices[BASE_SLICE+i-1];
 191                 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE,
 192                                WHOLE_SLICE_PART, partname);
 193
 194                 if (kuuid_is_nil(&sent.ent_type))
 195                         continue;
 196
 197                 if (sent.ent_lba_start < table_lba + table_blocks ||
 198                     sent.ent_lba_end >= info->d_media_blocks ||
 199                     sent.ent_lba_start >= sent.ent_lba_end) {
 200                         kprintf("%s part %d: unavailable, bad start or "
 201                                 "ending lba\n",
 202                                 sname, i);
 203                 } else {
 204                         gpt_setslice(sname, info, sp, &sent);
 205                 }
 206         }
 207         ssp->dss_nslices = BASE_SLICE + i;
 208
 209         error = 0;
 210 done:
 211         if (bp1) {
 212                 bp1->b_flags |= B_INVAL | B_AGE;
 213                 brelse(bp1);
 214         }
 215         if (bp2) {
 216                 bp2->b_flags |= B_INVAL | B_AGE;
 217                 brelse(bp2);
 218         }
 219         if (error == EINVAL)
 220                 error = 0;
 221         return (error);
 222 }
 223
 224 static
 225 void
 226 gpt_setslice(const char *sname, struct disk_info *info, struct diskslice *sp,
 227              struct gpt_ent *sent)
 228 {
 229         sp->ds_offset = sent->ent_lba_start;
 230         sp->ds_size   = sent->ent_lba_end + 1 - sent->ent_lba_start;
 231         sp->ds_type   = 1;      /* XXX */
 232         sp->ds_type_uuid = sent->ent_type;
 233         sp->ds_stor_uuid = sent->ent_uuid;
 234         sp->ds_reserved = 0;    /* no reserved sectors */
 235 }
 236