/* * Attempt to find the device from which we were booted. If we can do so, * and not instructed not to do so, change rootdev to correspond to the * load device. */ static void findroot(void) { struct btinfo_bootdisk *bid; struct device *dv; if (booted_device) return; if ((bid = lookup_bootinfo(BTINFO_BOOTDISK)) != NULL) { /* * Scan all disk devices for ones that match the passed data. * Don't break if one is found, to get possible multiple * matches - for problem tracking. Use the first match anyway * because lower device numbers are more likely to be the * boot device. */ for (dv = TAILQ_FIRST(&alldevs); dv != NULL; dv = TAILQ_NEXT(dv, dv_list)) { if (dv->dv_class != DV_DISK) continue; if (is_valid_disk(dv)) { if (match_bootdisk(dv, bid) == 0) continue; goto bootdisk_found; } continue; bootdisk_found: if (booted_device) { printf("WARNING: double match for boot " "device (%s, %s)\n", booted_device->dv_xname, dv->dv_xname); continue; } booted_device = dv; booted_partition = bid->partition; } if (booted_device) return; } }
/* * Attempt to find the device from which we were booted. If we can do so, * and not instructed not to do so, change rootdev to correspond to the * load device. */ static void findroot(void) { struct btinfo_rootdevice *biv; struct btinfo_bootdisk *bid; struct btinfo_bootwedge *biw; struct btinfo_biosgeom *big; device_t dv; deviter_t di; if (booted_device) return; if (lookup_bootinfo(BTINFO_NETIF) != NULL) { /* * We got netboot interface information, but device_register() * failed to match it to a configured device. Boot disk * information cannot be present at the same time, so give * up. */ printf("%s: netboot interface not found.\n", __func__); return; } if ((biv = lookup_bootinfo(BTINFO_ROOTDEVICE)) != NULL) { for (dv = deviter_first(&di, DEVITER_F_ROOT_FIRST); dv != NULL; dv = deviter_next(&di)) { cfdata_t cd; size_t len; if (device_class(dv) != DV_DISK) continue; cd = device_cfdata(dv); len = strlen(cd->cf_name); if (strncmp(cd->cf_name, biv->devname, len) == 0 && biv->devname[len] - '0' == device_unit(dv)) { booted_device = dv; booted_partition = biv->devname[len + 1] - 'a'; booted_nblks = 0; break; } } DPRINTF(("%s: BTINFO_ROOTDEVICE %s\n", __func__, booted_device ? device_xname(booted_device) : "not found")); deviter_release(&di); if (dv != NULL) return; } bid = lookup_bootinfo(BTINFO_BOOTDISK); biw = lookup_bootinfo(BTINFO_BOOTWEDGE); if (biw != NULL) { /* * Scan all disk devices for ones that match the passed data. * Don't break if one is found, to get possible multiple * matches - for problem tracking. Use the first match anyway * because lower devices numbers are more likely to be the * boot device. */ for (dv = deviter_first(&di, DEVITER_F_ROOT_FIRST); dv != NULL; dv = deviter_next(&di)) { if (is_valid_disk(dv)) { /* * Don't trust BIOS device numbers, try * to match the information passed by the * boot loader instead. */ if ((biw->biosdev & 0x80) == 0 || match_bootwedge(dv, biw) == 0) continue; goto bootwedge_found; } continue; bootwedge_found: if (booted_device) { dmatch(__func__, dv); continue; } booted_device = dv; booted_partition = bid != NULL ? bid->partition : 0; booted_nblks = biw->nblks; booted_startblk = biw->startblk; } deviter_release(&di); DPRINTF(("%s: BTINFO_BOOTWEDGE %s\n", __func__, booted_device ? device_xname(booted_device) : "not found")); if (booted_nblks) return; } if (bid != NULL) { /* * Scan all disk devices for ones that match the passed data. * Don't break if one is found, to get possible multiple * matches - for problem tracking. Use the first match anyway * because lower device numbers are more likely to be the * boot device. */ for (dv = deviter_first(&di, DEVITER_F_ROOT_FIRST); dv != NULL; dv = deviter_next(&di)) { if (device_is_a(dv, "fd") && device_class(dv) == DV_DISK) { /* * Assume the configured unit number matches * the BIOS device number. (This is the old * behavior.) Needs some ideas how to handle * the BIOS's "swap floppy drive" options. */ /* XXX device_unit() abuse */ if ((bid->biosdev & 0x80) != 0 || device_unit(dv) != bid->biosdev) continue; goto bootdisk_found; } if (is_valid_disk(dv)) { /* * Don't trust BIOS device numbers, try * to match the information passed by the * boot loader instead. */ if ((bid->biosdev & 0x80) == 0 || match_bootdisk(dv, bid) == 0) continue; goto bootdisk_found; } continue; bootdisk_found: if (booted_device) { dmatch(__func__, dv); continue; } booted_device = dv; booted_partition = bid->partition; booted_nblks = 0; } deviter_release(&di); DPRINTF(("%s: BTINFO_BOOTDISK %s\n", __func__, booted_device ? device_xname(booted_device) : "not found")); if (booted_device) return; /* * No booted device found; check CD-ROM boot at last. * * Our bootloader assumes CD-ROM boot if biosdev is larger * or equal than the number of hard drives recognized by the * BIOS. The number of drives can be found in BTINFO_BIOSGEOM * here. For example, if we have wd0, wd1, and cd0: * * big->num = 2 (for wd0 and wd1) * bid->biosdev = 0x80 (wd0) * bid->biosdev = 0x81 (wd1) * bid->biosdev = 0x82 (cd0) * * See src/sys/arch/i386/stand/boot/devopen.c and * src/sys/arch/i386/stand/lib/bootinfo_biosgeom.c . */ if ((big = lookup_bootinfo(BTINFO_BIOSGEOM)) != NULL && bid->biosdev >= 0x80 + big->num) { /* * XXX * There is no proper way to detect which unit is * recognized as a bootable CD-ROM drive by the BIOS. * Assume the first unit is the one. */ for (dv = deviter_first(&di, DEVITER_F_ROOT_FIRST); dv != NULL; dv = deviter_next(&di)) { if (device_class(dv) == DV_DISK && device_is_a(dv, "cd")) { booted_device = dv; booted_partition = 0; booted_nblks = 0; break; } } deviter_release(&di); DPRINTF(("%s: BTINFO_BIOSGEOM %s\n", __func__, booted_device ? device_xname(booted_device) : "not found")); } } }