| File: | arch/amd64/amd64/dkcsum.c |
| Warning: | line 125, column 4 Value stored to 'error' is never read |
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| 1 | /* $OpenBSD: dkcsum.c,v 1.21 2014/09/14 14:17:23 jsg Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1997 Niklas Hallqvist. 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 ``AS IS'' AND ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | /* |
| 28 | * A checksumming pseudo device used to get unique labels of each disk |
| 29 | * that needs to be matched to BIOS disks. |
| 30 | */ |
| 31 | |
| 32 | #include <sys/param.h> |
| 33 | #include <sys/buf.h> |
| 34 | #include <sys/conf.h> |
| 35 | #include <sys/device.h> |
| 36 | #include <sys/disklabel.h> |
| 37 | #include <sys/fcntl.h> |
| 38 | #include <sys/reboot.h> |
| 39 | #include <sys/stat.h> |
| 40 | #include <sys/systm.h> |
| 41 | |
| 42 | #include <machine/biosvar.h> |
| 43 | |
| 44 | #include <lib/libz/zlib.h> |
| 45 | |
| 46 | dev_t dev_rawpart(struct device *); /* XXX */ |
| 47 | |
| 48 | extern u_int32_t bios_cksumlen; |
| 49 | extern bios_diskinfo_t *bios_diskinfo; |
| 50 | extern dev_t bootdev; |
| 51 | |
| 52 | void |
| 53 | dkcsumattach(void) |
| 54 | { |
| 55 | struct device *dv; |
| 56 | struct buf *bp; |
| 57 | struct bdevsw *bdsw; |
| 58 | dev_t dev, pribootdev, altbootdev; |
| 59 | int error, picked; |
| 60 | u_int32_t csum; |
| 61 | bios_diskinfo_t *bdi, *hit; |
| 62 | |
| 63 | /* do nothing if no diskinfo passed from /boot, or a bad length */ |
| 64 | if (bios_diskinfo == NULL((void *)0) || bios_cksumlen * DEV_BSIZE(1 << 9) > MAXBSIZE(64 * 1024)) |
| 65 | return; |
| 66 | |
| 67 | /* Do nothing if bootdev is a CD drive. */ |
| 68 | if (B_TYPE(bootdev)(((bootdev) >> 0) & 0xff) == 6) |
| 69 | return; |
| 70 | |
| 71 | #ifdef DEBUG |
| 72 | printf("dkcsum: bootdev=%#x\n", bootdev); |
| 73 | for (bdi = bios_diskinfo; bdi->bios_number != -1; bdi++) { |
| 74 | if (bdi->bios_number & 0x80) { |
| 75 | printf("dkcsum: BIOS drive %#x bsd_dev=%#x " |
| 76 | "checksum=%#x\n", bdi->bios_number, bdi->bsd_dev, |
| 77 | bdi->checksum); |
| 78 | } |
| 79 | } |
| 80 | #endif |
| 81 | pribootdev = altbootdev = 0; |
| 82 | |
| 83 | /* |
| 84 | * XXX What if DEV_BSIZE is changed to something else than the BIOS |
| 85 | * blocksize? Today, /boot doesn't cover that case so neither need |
| 86 | * I care here. |
| 87 | */ |
| 88 | bp = geteblk(bios_cksumlen * DEV_BSIZE(1 << 9)); /* XXX error check? */ |
| 89 | |
| 90 | TAILQ_FOREACH(dv, &alldevs, dv_list)for((dv) = ((&alldevs)->tqh_first); (dv) != ((void *)0 ); (dv) = ((dv)->dv_list.tqe_next)) { |
| 91 | if (dv->dv_class != DV_DISK) |
| 92 | continue; |
| 93 | bp->b_dev = dev = dev_rawpart(dv); |
| 94 | if (dev == NODEV(dev_t)(-1)) |
| 95 | continue; |
| 96 | bdsw = &bdevsw[major(dev)(((unsigned)(dev) >> 8) & 0xff)]; |
| 97 | |
| 98 | /* |
| 99 | * This open operation guarantees a proper initialization |
| 100 | * of the device, for future strategy calls. |
| 101 | */ |
| 102 | error = (*bdsw->d_open)(dev, FREAD0x0001, S_IFCHR0020000, curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc); |
| 103 | if (error) { |
| 104 | /* XXX What to do here? */ |
| 105 | #ifdef DEBUG |
| 106 | printf("dkcsum: %s open failed (%d)\n", |
| 107 | dv->dv_xname, error); |
| 108 | #endif |
| 109 | continue; |
| 110 | } |
| 111 | |
| 112 | /* Read blocks to cksum. XXX maybe a d_read should be used. */ |
| 113 | bp->b_blkno = 0; |
| 114 | bp->b_bcount = bios_cksumlen * DEV_BSIZE(1 << 9); |
| 115 | bp->b_error = 0; /* B_ERROR and b_error may have stale data. */ |
| 116 | CLR(bp->b_flags, B_READ | B_WRITE | B_DONE | B_ERROR)((bp->b_flags) &= ~(0x00008000 | 0x00000000 | 0x00000100 | 0x00000400)); |
| 117 | SET(bp->b_flags, B_BUSY | B_READ | B_RAW)((bp->b_flags) |= (0x00000010 | 0x00008000 | 0x00004000)); |
| 118 | (*bdsw->d_strategy)(bp); |
| 119 | if ((error = biowait(bp))) { |
| 120 | /* XXX What to do here? */ |
| 121 | #ifdef DEBUG |
| 122 | printf("dkcsum: %s read failed (%d)\n", |
| 123 | dv->dv_xname, error); |
| 124 | #endif |
| 125 | error = (*bdsw->d_close)(dev, 0, S_IFCHR0020000, curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc); |
Value stored to 'error' is never read | |
| 126 | #ifdef DEBUG |
| 127 | if (error) |
| 128 | printf("dkcsum: %s close failed (%d)\n", |
| 129 | dv->dv_xname, error); |
| 130 | #endif |
| 131 | continue; |
| 132 | } |
| 133 | error = (*bdsw->d_close)(dev, FREAD0x0001, S_IFCHR0020000, curproc({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof(struct cpu_info, ci_self))); __ci;})->ci_curproc); |
| 134 | if (error) { |
| 135 | /* XXX What to do here? */ |
| 136 | #ifdef DEBUG |
| 137 | printf("dkcsum: %s closed failed (%d)\n", |
| 138 | dv->dv_xname, error); |
| 139 | #endif |
| 140 | continue; |
| 141 | } |
| 142 | |
| 143 | csum = adler32(0, bp->b_data, bios_cksumlen * DEV_BSIZE(1 << 9)); |
| 144 | #ifdef DEBUG |
| 145 | printf("dkcsum: %s checksum is %#x\n", dv->dv_xname, csum); |
| 146 | #endif |
| 147 | |
| 148 | /* Find the BIOS device */ |
| 149 | hit = 0; |
| 150 | for (bdi = bios_diskinfo; bdi->bios_number != -1; bdi++) { |
| 151 | /* Skip non-harddrives */ |
| 152 | if (!(bdi->bios_number & 0x80)) |
| 153 | continue; |
| 154 | if (bdi->checksum != csum) |
| 155 | continue; |
| 156 | picked = hit || (bdi->flags & BDI_PICKED0x80000000); |
| 157 | if (!picked) |
| 158 | hit = bdi; |
| 159 | #ifdef DEBUG |
| 160 | printf("dkcsum: %s matches BIOS drive %#x%s\n", |
| 161 | dv->dv_xname, bdi->bios_number, |
| 162 | (picked ? " IGNORED" : "")); |
| 163 | #endif |
| 164 | } |
| 165 | |
| 166 | /* |
| 167 | * If we have no hit, that's OK, we can see a lot more devices |
| 168 | * than the BIOS can, so this case is pretty normal. |
| 169 | */ |
| 170 | if (!hit) { |
| 171 | #ifdef DEBUG |
| 172 | printf("dkcsum: %s has no matching BIOS drive\n", |
| 173 | dv->dv_xname); |
| 174 | #endif |
| 175 | continue; |
| 176 | } |
| 177 | |
| 178 | /* |
| 179 | * Fixup bootdev if units match. This means that all of |
| 180 | * hd*, sd*, wd*, will be interpreted the same. Not 100% |
| 181 | * backwards compatible, but sd* and wd* should be phased- |
| 182 | * out in the bootblocks. |
| 183 | */ |
| 184 | |
| 185 | /* B_TYPE dependent hd unit counting bootblocks */ |
| 186 | if ((B_ADAPTOR(bootdev)(((bootdev) >> 24) & 0x0f) == B_ADAPTOR(hit->bsd_dev)(((hit->bsd_dev) >> 24) & 0x0f)) && |
| 187 | (B_CONTROLLER(bootdev)(((bootdev)>>20) & 0xf) == B_CONTROLLER(hit->bsd_dev)(((hit->bsd_dev)>>20) & 0xf)) && |
| 188 | (B_TYPE(bootdev)(((bootdev) >> 0) & 0xff) == B_TYPE(hit->bsd_dev)(((hit->bsd_dev) >> 0) & 0xff)) && |
| 189 | (B_UNIT(bootdev)(((bootdev) >> 16) & 0xf) == B_UNIT(hit->bsd_dev)(((hit->bsd_dev) >> 16) & 0xf))) { |
| 190 | int type, ctrl, adap, part, unit; |
| 191 | |
| 192 | type = major(bp->b_dev)(((unsigned)(bp->b_dev) >> 8) & 0xff); |
| 193 | adap = B_ADAPTOR(bootdev)(((bootdev) >> 24) & 0x0f); |
| 194 | ctrl = B_CONTROLLER(bootdev)(((bootdev)>>20) & 0xf); |
| 195 | unit = DISKUNIT(bp->b_dev)(((unsigned)((bp->b_dev) & 0xff) | (((bp->b_dev) & 0xffff0000) >> 8)) / 16); |
| 196 | part = B_PARTITION(bootdev)(((bootdev) >> 8) & 0xff); |
| 197 | |
| 198 | pribootdev = MAKEBOOTDEV(type, ctrl, adap, unit, part)(((type) << 0) | ((ctrl) << 24) | ((adap) << 20) | ((unit) << 16) | ((part) << 8) | 0xa0000000 ); |
| 199 | #ifdef DEBUG |
| 200 | printf("dkcsum: %s is primary boot disk\n", |
| 201 | dv->dv_xname); |
| 202 | #endif |
| 203 | } |
| 204 | /* B_TYPE independent hd unit counting bootblocks */ |
| 205 | if (B_UNIT(bootdev)(((bootdev) >> 16) & 0xf) == (hit->bios_number & 0x7F)) { |
| 206 | int type, ctrl, adap, part, unit; |
| 207 | |
| 208 | type = major(bp->b_dev)(((unsigned)(bp->b_dev) >> 8) & 0xff); |
| 209 | adap = B_ADAPTOR(bootdev)(((bootdev) >> 24) & 0x0f); |
| 210 | ctrl = B_CONTROLLER(bootdev)(((bootdev)>>20) & 0xf); |
| 211 | unit = DISKUNIT(bp->b_dev)(((unsigned)((bp->b_dev) & 0xff) | (((bp->b_dev) & 0xffff0000) >> 8)) / 16); |
| 212 | part = B_PARTITION(bootdev)(((bootdev) >> 8) & 0xff); |
| 213 | |
| 214 | altbootdev = MAKEBOOTDEV(type, ctrl, adap, unit, part)(((type) << 0) | ((ctrl) << 24) | ((adap) << 20) | ((unit) << 16) | ((part) << 8) | 0xa0000000 ); |
| 215 | #ifdef DEBUG |
| 216 | printf("dkcsum: %s is alternate boot disk\n", |
| 217 | dv->dv_xname); |
| 218 | #endif |
| 219 | } |
| 220 | |
| 221 | /* This will overwrite /boot's guess, just so you remember */ |
| 222 | hit->bsd_dev = MAKEBOOTDEV(major(bp->b_dev), 0, 0,((((((unsigned)(bp->b_dev) >> 8) & 0xff)) << 0) | ((0) << 24) | ((0) << 20) | (((((unsigned)( (bp->b_dev) & 0xff) | (((bp->b_dev) & 0xffff0000 ) >> 8)) / 16)) << 16) | ((2) << 8) | 0xa0000000 ) |
| 223 | DISKUNIT(bp->b_dev), RAW_PART)((((((unsigned)(bp->b_dev) >> 8) & 0xff)) << 0) | ((0) << 24) | ((0) << 20) | (((((unsigned)( (bp->b_dev) & 0xff) | (((bp->b_dev) & 0xffff0000 ) >> 8)) / 16)) << 16) | ((2) << 8) | 0xa0000000 ); |
| 224 | hit->flags |= BDI_PICKED0x80000000; |
| 225 | } |
| 226 | bootdev = pribootdev ? pribootdev : altbootdev ? altbootdev : bootdev; |
| 227 | |
| 228 | bp->b_flags |= B_INVAL0x00000800; |
| 229 | brelse(bp); |
| 230 | } |