diff options
Diffstat (limited to 'src/pc-bios/s390-ccw/bootmap.c')
| -rw-r--r-- | src/pc-bios/s390-ccw/bootmap.c | 701 |
1 files changed, 701 insertions, 0 deletions
diff --git a/src/pc-bios/s390-ccw/bootmap.c b/src/pc-bios/s390-ccw/bootmap.c new file mode 100644 index 0000000..415508b --- /dev/null +++ b/src/pc-bios/s390-ccw/bootmap.c @@ -0,0 +1,701 @@ +/* + * QEMU S390 bootmap interpreter + * + * Copyright (c) 2009 Alexander Graf <agraf@suse.de> + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#include "s390-ccw.h" +#include "bootmap.h" +#include "virtio.h" + +#ifdef DEBUG +/* #define DEBUG_FALLBACK */ +#endif + +#ifdef DEBUG_FALLBACK +#define dputs(txt) \ + do { sclp_print("zipl: " txt); } while (0) +#else +#define dputs(fmt, ...) \ + do { } while (0) +#endif + +/* Scratch space */ +static uint8_t sec[MAX_SECTOR_SIZE*4] __attribute__((__aligned__(PAGE_SIZE))); + +typedef struct ResetInfo { + uint32_t ipl_mask; + uint32_t ipl_addr; + uint32_t ipl_continue; +} ResetInfo; + +static ResetInfo save; + +static void jump_to_IPL_2(void) +{ + ResetInfo *current = 0; + + void (*ipl)(void) = (void *) (uint64_t) current->ipl_continue; + *current = save; + ipl(); /* should not return */ +} + +static void jump_to_IPL_code(uint64_t address) +{ + /* store the subsystem information _after_ the bootmap was loaded */ + write_subsystem_identification(); + /* + * The IPL PSW is at address 0. We also must not overwrite the + * content of non-BIOS memory after we loaded the guest, so we + * save the original content and restore it in jump_to_IPL_2. + */ + ResetInfo *current = 0; + + save = *current; + current->ipl_addr = (uint32_t) (uint64_t) &jump_to_IPL_2; + current->ipl_continue = address & 0x7fffffff; + + debug_print_int("set IPL addr to", current->ipl_continue); + + /* Ensure the guest output starts fresh */ + sclp_print("\n"); + + /* + * HACK ALERT. + * We use the load normal reset to keep r15 unchanged. jump_to_IPL_2 + * can then use r15 as its stack pointer. + */ + asm volatile("lghi 1,1\n\t" + "diag 1,1,0x308\n\t" + : : : "1", "memory"); + virtio_panic("\n! IPL returns !\n"); +} + +/*********************************************************************** + * IPL an ECKD DASD (CDL or LDL/CMS format) + */ + +static unsigned char _bprs[8*1024]; /* guessed "max" ECKD sector size */ +static const int max_bprs_entries = sizeof(_bprs) / sizeof(ExtEckdBlockPtr); + +static inline void verify_boot_info(BootInfo *bip) +{ + IPL_assert(magic_match(bip->magic, ZIPL_MAGIC), "No zIPL magic"); + IPL_assert(bip->version == BOOT_INFO_VERSION, "Wrong zIPL version"); + IPL_assert(bip->bp_type == BOOT_INFO_BP_TYPE_IPL, "DASD is not for IPL"); + IPL_assert(bip->dev_type == BOOT_INFO_DEV_TYPE_ECKD, "DASD is not ECKD"); + IPL_assert(bip->flags == BOOT_INFO_FLAGS_ARCH, "Not for this arch"); + IPL_assert(block_size_ok(bip->bp.ipl.bm_ptr.eckd.bptr.size), + "Bad block size in zIPL section of the 1st record."); +} + +static block_number_t eckd_block_num(BootMapPointer *p) +{ + const uint64_t sectors = virtio_get_sectors(); + const uint64_t heads = virtio_get_heads(); + const uint64_t cylinder = p->eckd.cylinder + + ((p->eckd.head & 0xfff0) << 12); + const uint64_t head = p->eckd.head & 0x000f; + const block_number_t block = sectors * heads * cylinder + + sectors * head + + p->eckd.sector + - 1; /* block nr starts with zero */ + return block; +} + +static bool eckd_valid_address(BootMapPointer *p) +{ + const uint64_t head = p->eckd.head & 0x000f; + + if (head >= virtio_get_heads() + || p->eckd.sector > virtio_get_sectors() + || p->eckd.sector <= 0) { + return false; + } + + if (!virtio_guessed_disk_nature() && + eckd_block_num(p) >= virtio_get_blocks()) { + return false; + } + + return true; +} + +static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address) +{ + block_number_t block_nr; + int j, rc; + BootMapPointer *bprs = (void *)_bprs; + bool more_data; + + memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs)); + read_block(blk, bprs, "BPRS read failed"); + + do { + more_data = false; + for (j = 0;; j++) { + block_nr = eckd_block_num((void *)&(bprs[j].xeckd)); + if (is_null_block_number(block_nr)) { /* end of chunk */ + break; + } + + /* we need the updated blockno for the next indirect entry + * in the chain, but don't want to advance address + */ + if (j == (max_bprs_entries - 1)) { + break; + } + + IPL_assert(block_size_ok(bprs[j].xeckd.bptr.size), + "bad chunk block size"); + IPL_assert(eckd_valid_address(&bprs[j]), "bad chunk ECKD addr"); + + if ((bprs[j].xeckd.bptr.count == 0) && unused_space(&(bprs[j+1]), + sizeof(EckdBlockPtr))) { + /* This is a "continue" pointer. + * This ptr should be the last one in the current + * script section. + * I.e. the next ptr must point to the unused memory area + */ + memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs)); + read_block(block_nr, bprs, "BPRS continuation read failed"); + more_data = true; + break; + } + + /* Load (count+1) blocks of code at (block_nr) + * to memory (address). + */ + rc = virtio_read_many(block_nr, (void *)(*address), + bprs[j].xeckd.bptr.count+1); + IPL_assert(rc == 0, "code chunk read failed"); + + *address += (bprs[j].xeckd.bptr.count+1) * virtio_get_block_size(); + } + } while (more_data); + return block_nr; +} + +static void run_eckd_boot_script(block_number_t mbr_block_nr) +{ + int i; + block_number_t block_nr; + uint64_t address; + ScsiMbr *scsi_mbr = (void *)sec; + BootMapScript *bms = (void *)sec; + + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(mbr_block_nr, sec, "Cannot read MBR"); + + block_nr = eckd_block_num((void *)&(scsi_mbr->blockptr)); + + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(block_nr, sec, "Cannot read Boot Map Script"); + + for (i = 0; bms->entry[i].type == BOOT_SCRIPT_LOAD; i++) { + address = bms->entry[i].address.load_address; + block_nr = eckd_block_num(&(bms->entry[i].blkptr)); + + do { + block_nr = load_eckd_segments(block_nr, &address); + } while (block_nr != -1); + } + + IPL_assert(bms->entry[i].type == BOOT_SCRIPT_EXEC, + "Unknown script entry type"); + jump_to_IPL_code(bms->entry[i].address.load_address); /* no return */ +} + +static void ipl_eckd_cdl(void) +{ + XEckdMbr *mbr; + Ipl2 *ipl2 = (void *)sec; + IplVolumeLabel *vlbl = (void *)sec; + block_number_t block_nr; + + /* we have just read the block #0 and recognized it as "IPL1" */ + sclp_print("CDL\n"); + + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(1, ipl2, "Cannot read IPL2 record at block 1"); + + mbr = &ipl2->u.x.mbr; + IPL_assert(magic_match(mbr, ZIPL_MAGIC), "No zIPL section in IPL2 record."); + IPL_assert(block_size_ok(mbr->blockptr.xeckd.bptr.size), + "Bad block size in zIPL section of IPL2 record."); + IPL_assert(mbr->dev_type == DEV_TYPE_ECKD, + "Non-ECKD device type in zIPL section of IPL2 record."); + + /* save pointer to Boot Script */ + block_nr = eckd_block_num((void *)&(mbr->blockptr)); + + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(2, vlbl, "Cannot read Volume Label at block 2"); + IPL_assert(magic_match(vlbl->key, VOL1_MAGIC), + "Invalid magic of volume label block"); + IPL_assert(magic_match(vlbl->f.key, VOL1_MAGIC), + "Invalid magic of volser block"); + print_volser(vlbl->f.volser); + + run_eckd_boot_script(block_nr); + /* no return */ +} + +static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode) +{ + LDL_VTOC *vlbl = (void *)sec; /* already read, 3rd block */ + char msg[4] = { '?', '.', '\n', '\0' }; + + sclp_print((mode == ECKD_CMS) ? "CMS" : "LDL"); + sclp_print(" version "); + switch (vlbl->LDL_version) { + case LDL1_VERSION: + msg[0] = '1'; + break; + case LDL2_VERSION: + msg[0] = '2'; + break; + default: + msg[0] = vlbl->LDL_version; + msg[0] &= 0x0f; /* convert EBCDIC */ + msg[0] |= 0x30; /* to ASCII (digit) */ + msg[1] = '?'; + break; + } + sclp_print(msg); + print_volser(vlbl->volser); +} + +static void ipl_eckd_ldl(ECKD_IPL_mode_t mode) +{ + block_number_t block_nr; + BootInfo *bip = (void *)(sec + 0x70); /* BootInfo is MBR for LDL */ + + if (mode != ECKD_LDL_UNLABELED) { + print_eckd_ldl_msg(mode); + } + + /* DO NOT read BootMap pointer (only one, xECKD) at block #2 */ + + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(0, sec, "Cannot read block 0 to grab boot info."); + if (mode == ECKD_LDL_UNLABELED) { + if (!magic_match(bip->magic, ZIPL_MAGIC)) { + return; /* not applicable layout */ + } + sclp_print("unlabeled LDL.\n"); + } + verify_boot_info(bip); + + block_nr = eckd_block_num((void *)&(bip->bp.ipl.bm_ptr.eckd.bptr)); + run_eckd_boot_script(block_nr); + /* no return */ +} + +static void print_eckd_msg(void) +{ + char msg[] = "Using ECKD scheme (block size *****), "; + char *p = &msg[34], *q = &msg[30]; + int n = virtio_get_block_size(); + + /* Fill in the block size and show up the message */ + if (n > 0 && n <= 99999) { + while (n) { + *p-- = '0' + (n % 10); + n /= 10; + } + while (p >= q) { + *p-- = ' '; + } + } + sclp_print(msg); +} + +/*********************************************************************** + * IPL a SCSI disk + */ + +static void zipl_load_segment(ComponentEntry *entry) +{ + const int max_entries = (MAX_SECTOR_SIZE / sizeof(ScsiBlockPtr)); + ScsiBlockPtr *bprs = (void *)sec; + const int bprs_size = sizeof(sec); + block_number_t blockno; + uint64_t address; + int i; + char err_msg[] = "zIPL failed to read BPRS at 0xZZZZZZZZZZZZZZZZ"; + char *blk_no = &err_msg[30]; /* where to print blockno in (those ZZs) */ + + blockno = entry->data.blockno; + address = entry->load_address; + + debug_print_int("loading segment at block", blockno); + debug_print_int("addr", address); + + do { + memset(bprs, FREE_SPACE_FILLER, bprs_size); + fill_hex_val(blk_no, &blockno, sizeof(blockno)); + read_block(blockno, bprs, err_msg); + + for (i = 0;; i++) { + uint64_t *cur_desc = (void *)&bprs[i]; + + blockno = bprs[i].blockno; + if (!blockno) { + break; + } + + /* we need the updated blockno for the next indirect entry in the + chain, but don't want to advance address */ + if (i == (max_entries - 1)) { + break; + } + + if (bprs[i].blockct == 0 && unused_space(&bprs[i + 1], + sizeof(ScsiBlockPtr))) { + /* This is a "continue" pointer. + * This ptr is the last one in the current script section. + * I.e. the next ptr must point to the unused memory area. + * The blockno is not zero, so the upper loop must continue + * reading next section of BPRS. + */ + break; + } + address = virtio_load_direct(cur_desc[0], cur_desc[1], 0, + (void *)address); + IPL_assert(address != -1, "zIPL load segment failed"); + } + } while (blockno); +} + +/* Run a zipl program */ +static void zipl_run(ScsiBlockPtr *pte) +{ + ComponentHeader *header; + ComponentEntry *entry; + uint8_t tmp_sec[MAX_SECTOR_SIZE]; + + read_block(pte->blockno, tmp_sec, "Cannot read header"); + header = (ComponentHeader *)tmp_sec; + + IPL_assert(magic_match(tmp_sec, ZIPL_MAGIC), "No zIPL magic"); + IPL_assert(header->type == ZIPL_COMP_HEADER_IPL, "Bad header type"); + + dputs("start loading images\n"); + + /* Load image(s) into RAM */ + entry = (ComponentEntry *)(&header[1]); + while (entry->component_type == ZIPL_COMP_ENTRY_LOAD) { + zipl_load_segment(entry); + + entry++; + + IPL_assert((uint8_t *)(&entry[1]) <= (tmp_sec + MAX_SECTOR_SIZE), + "Wrong entry value"); + } + + IPL_assert(entry->component_type == ZIPL_COMP_ENTRY_EXEC, "No EXEC entry"); + + /* should not return */ + jump_to_IPL_code(entry->load_address); +} + +static void ipl_scsi(void) +{ + ScsiMbr *mbr = (void *)sec; + uint8_t *ns, *ns_end; + int program_table_entries = 0; + const int pte_len = sizeof(ScsiBlockPtr); + ScsiBlockPtr *prog_table_entry; + + /* The 0-th block (MBR) was already read into sec[] */ + + sclp_print("Using SCSI scheme.\n"); + debug_print_int("program table", mbr->blockptr.blockno); + + /* Parse the program table */ + read_block(mbr->blockptr.blockno, sec, + "Error reading Program Table"); + + IPL_assert(magic_match(sec, ZIPL_MAGIC), "No zIPL magic"); + + ns_end = sec + virtio_get_block_size(); + for (ns = (sec + pte_len); (ns + pte_len) < ns_end; ns++) { + prog_table_entry = (ScsiBlockPtr *)ns; + if (!prog_table_entry->blockno) { + break; + } + + program_table_entries++; + } + + debug_print_int("program table entries", program_table_entries); + + IPL_assert(program_table_entries != 0, "Empty Program Table"); + + /* Run the default entry */ + + prog_table_entry = (ScsiBlockPtr *)(sec + pte_len); + + zipl_run(prog_table_entry); /* no return */ +} + +/*********************************************************************** + * IPL El Torito ISO9660 image or DVD + */ + +static bool is_iso_bc_entry_compatible(IsoBcSection *s) +{ + uint8_t *magic_sec = (uint8_t *)(sec + ISO_SECTOR_SIZE); + + if (s->unused || !s->sector_count) { + return false; + } + read_iso_sector(bswap32(s->load_rba), magic_sec, + "Failed to read image sector 0"); + + /* Checking bytes 8 - 32 for S390 Linux magic */ + return !_memcmp(magic_sec + 8, linux_s390_magic, 24); +} + +/* Location of the current sector of the directory */ +static uint32_t sec_loc[ISO9660_MAX_DIR_DEPTH]; +/* Offset in the current sector of the directory */ +static uint32_t sec_offset[ISO9660_MAX_DIR_DEPTH]; +/* Remained directory space in bytes */ +static uint32_t dir_rem[ISO9660_MAX_DIR_DEPTH]; + +static inline uint32_t iso_get_file_size(uint32_t load_rba) +{ + IsoVolDesc *vd = (IsoVolDesc *)sec; + IsoDirHdr *cur_record = &vd->vd.primary.rootdir; + uint8_t *temp = sec + ISO_SECTOR_SIZE; + int level = 0; + + read_iso_sector(ISO_PRIMARY_VD_SECTOR, sec, + "Failed to read ISO primary descriptor"); + sec_loc[0] = iso_733_to_u32(cur_record->ext_loc); + dir_rem[0] = 0; + sec_offset[0] = 0; + + while (level >= 0) { + IPL_assert(sec_offset[level] <= ISO_SECTOR_SIZE, + "Directory tree structure violation"); + + cur_record = (IsoDirHdr *)(temp + sec_offset[level]); + + if (sec_offset[level] == 0) { + read_iso_sector(sec_loc[level], temp, + "Failed to read ISO directory"); + if (dir_rem[level] == 0) { + /* Skip self and parent records */ + dir_rem[level] = iso_733_to_u32(cur_record->data_len) - + cur_record->dr_len; + sec_offset[level] += cur_record->dr_len; + + cur_record = (IsoDirHdr *)(temp + sec_offset[level]); + dir_rem[level] -= cur_record->dr_len; + sec_offset[level] += cur_record->dr_len; + continue; + } + } + + if (!cur_record->dr_len || sec_offset[level] == ISO_SECTOR_SIZE) { + /* Zero-padding and/or the end of current sector */ + dir_rem[level] -= ISO_SECTOR_SIZE - sec_offset[level]; + sec_offset[level] = 0; + sec_loc[level]++; + } else { + /* The directory record is valid */ + if (load_rba == iso_733_to_u32(cur_record->ext_loc)) { + return iso_733_to_u32(cur_record->data_len); + } + + dir_rem[level] -= cur_record->dr_len; + sec_offset[level] += cur_record->dr_len; + + if (cur_record->file_flags & 0x2) { + /* Subdirectory */ + if (level == ISO9660_MAX_DIR_DEPTH - 1) { + sclp_print("ISO-9660 directory depth limit exceeded\n"); + } else { + level++; + sec_loc[level] = iso_733_to_u32(cur_record->ext_loc); + sec_offset[level] = 0; + dir_rem[level] = 0; + continue; + } + } + } + + if (dir_rem[level] == 0) { + /* Nothing remaining */ + level--; + read_iso_sector(sec_loc[level], temp, + "Failed to read ISO directory"); + } + } + + return 0; +} + +static void load_iso_bc_entry(IsoBcSection *load) +{ + IsoBcSection s = *load; + /* + * According to spec, extent for each file + * is padded and ISO_SECTOR_SIZE bytes aligned + */ + uint32_t blks_to_load = bswap16(s.sector_count) >> ET_SECTOR_SHIFT; + uint32_t real_size = iso_get_file_size(bswap32(s.load_rba)); + + if (real_size) { + /* Round up blocks to load */ + blks_to_load = (real_size + ISO_SECTOR_SIZE - 1) / ISO_SECTOR_SIZE; + sclp_print("ISO boot image size verified\n"); + } else { + sclp_print("ISO boot image size could not be verified\n"); + } + + read_iso_boot_image(bswap32(s.load_rba), + (void *)((uint64_t)bswap16(s.load_segment)), + blks_to_load); + + /* Trying to get PSW at zero address */ + if (*((uint64_t *)0) & IPL_PSW_MASK) { + jump_to_IPL_code((*((uint64_t *)0)) & 0x7fffffff); + } + + /* Try default linux start address */ + jump_to_IPL_code(KERN_IMAGE_START); +} + +static uint32_t find_iso_bc(void) +{ + IsoVolDesc *vd = (IsoVolDesc *)sec; + uint32_t block_num = ISO_PRIMARY_VD_SECTOR; + + if (virtio_read_many(block_num++, sec, 1)) { + /* If primary vd cannot be read, there is no boot catalog */ + return 0; + } + + while (is_iso_vd_valid(vd) && vd->type != VOL_DESC_TERMINATOR) { + if (vd->type == VOL_DESC_TYPE_BOOT) { + IsoVdElTorito *et = &vd->vd.boot; + + if (!_memcmp(&et->el_torito[0], el_torito_magic, 32)) { + return bswap32(et->bc_offset); + } + } + read_iso_sector(block_num++, sec, + "Failed to read ISO volume descriptor"); + } + + return 0; +} + +static IsoBcSection *find_iso_bc_entry(void) +{ + IsoBcEntry *e = (IsoBcEntry *)sec; + uint32_t offset = find_iso_bc(); + int i; + + if (!offset) { + return NULL; + } + + read_iso_sector(offset, sec, "Failed to read El Torito boot catalog"); + + if (!is_iso_bc_valid(e)) { + /* The validation entry is mandatory */ + virtio_panic("No valid boot catalog found!\n"); + return NULL; + } + + /* + * Each entry has 32 bytes size, so one sector cannot contain > 64 entries. + * We consider only boot catalogs with no more than 64 entries. + */ + for (i = 1; i < ISO_BC_ENTRY_PER_SECTOR; i++) { + if (e[i].id == ISO_BC_BOOTABLE_SECTION) { + if (is_iso_bc_entry_compatible(&e[i].body.sect)) { + return &e[i].body.sect; + } + } + } + + virtio_panic("No suitable boot entry found on ISO-9660 media!\n"); + + return NULL; +} + +static void ipl_iso_el_torito(void) +{ + IsoBcSection *s = find_iso_bc_entry(); + + if (s) { + load_iso_bc_entry(s); + /* no return */ + } +} + +/*********************************************************************** + * IPL starts here + */ + +void zipl_load(void) +{ + ScsiMbr *mbr = (void *)sec; + LDL_VTOC *vlbl = (void *)sec; + + /* Grab the MBR */ + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(0, mbr, "Cannot read block 0"); + + dputs("checking magic\n"); + + if (magic_match(mbr->magic, ZIPL_MAGIC)) { + ipl_scsi(); /* no return */ + } + + /* Check if we can boot as ISO media */ + if (virtio_guessed_disk_nature()) { + virtio_assume_iso9660(); + } + ipl_iso_el_torito(); + + /* We have failed to follow the SCSI scheme, so */ + if (virtio_guessed_disk_nature()) { + sclp_print("Using guessed DASD geometry.\n"); + virtio_assume_eckd(); + } + print_eckd_msg(); + if (magic_match(mbr->magic, IPL1_MAGIC)) { + ipl_eckd_cdl(); /* no return */ + } + + /* LDL/CMS? */ + memset(sec, FREE_SPACE_FILLER, sizeof(sec)); + read_block(2, vlbl, "Cannot read block 2"); + + if (magic_match(vlbl->magic, CMS1_MAGIC)) { + ipl_eckd_ldl(ECKD_CMS); /* no return */ + } + if (magic_match(vlbl->magic, LNX1_MAGIC)) { + ipl_eckd_ldl(ECKD_LDL); /* no return */ + } + + ipl_eckd_ldl(ECKD_LDL_UNLABELED); /* it still may return */ + /* + * Ok, it is not a LDL by any means. + * It still might be a CDL with zero record keys for IPL1 and IPL2 + */ + ipl_eckd_cdl(); + + virtio_panic("\n* this can never happen *\n"); +} |
