pc-bios/s390-ccw/bootmap.c

   1 /*
   2  * QEMU S390 bootmap interpreter
   3  *
   4  * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2 or (at
   7  * your option) any later version. See the COPYING file in the top-level
   8  * directory.
   9  */
  10
  11 #include "libc.h"
  12 #include "s390-ccw.h"
  13 #include "s390-arch.h"
  14 #include "bootmap.h"
  15 #include "virtio.h"
  16 #include "bswap.h"
  17
  18 #ifdef DEBUG
  19 /* #define DEBUG_FALLBACK */
  20 #endif
  21
  22 #ifdef DEBUG_FALLBACK
  23 #define dputs(txt) \
  24     do { sclp_print("zipl: " txt); } while (0)
  25 #else
  26 #define dputs(fmt, ...) \
  27     do { } while (0)
  28 #endif
  29
  30 /* Scratch space */
  31 static uint8_t sec[MAX_SECTOR_SIZE*4] __attribute__((__aligned__(PAGE_SIZE)));
  32
  33 const uint8_t el_torito_magic[] = "EL TORITO SPECIFICATION"
  34                                   "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
  35
  36 /*
  37  * Match two CCWs located after PSW and eight filler bytes.
  38  * From libmagic and arch/s390/kernel/head.S.
  39  */
  40 const uint8_t linux_s390_magic[] = "\x02\x00\x00\x18\x60\x00\x00\x50\x02\x00"
  41                                    "\x00\x68\x60\x00\x00\x50\x40\x40\x40\x40"
  42                                    "\x40\x40\x40\x40";
  43
  44 static inline bool is_iso_vd_valid(IsoVolDesc *vd)
  45 {
  46     const uint8_t vol_desc_magic[] = "CD001";
  47
  48     return !memcmp(&vd->ident[0], vol_desc_magic, 5) &&
  49            vd->version == 0x1 &&
  50            vd->type <= VOL_DESC_TYPE_PARTITION;
  51 }
  52
  53 /***********************************************************************
  54  * IPL an ECKD DASD (CDL or LDL/CMS format)
  55  */
  56
  57 static unsigned char _bprs[8*1024]; /* guessed "max" ECKD sector size */
  58 static const int max_bprs_entries = sizeof(_bprs) / sizeof(ExtEckdBlockPtr);
  59 static uint8_t _s2[MAX_SECTOR_SIZE * 3] __attribute__((__aligned__(PAGE_SIZE)));
  60 static void *s2_prev_blk = _s2;
  61 static void *s2_cur_blk = _s2 + MAX_SECTOR_SIZE;
  62 static void *s2_next_blk = _s2 + MAX_SECTOR_SIZE * 2;
  63
  64 static inline void verify_boot_info(BootInfo *bip)
  65 {
  66     IPL_assert(magic_match(bip->magic, ZIPL_MAGIC), "No zIPL sig in BootInfo");
  67     IPL_assert(bip->version == BOOT_INFO_VERSION, "Wrong zIPL version");
  68     IPL_assert(bip->bp_type == BOOT_INFO_BP_TYPE_IPL, "DASD is not for IPL");
  69     IPL_assert(bip->dev_type == BOOT_INFO_DEV_TYPE_ECKD, "DASD is not ECKD");
  70     IPL_assert(bip->flags == BOOT_INFO_FLAGS_ARCH, "Not for this arch");
  71     IPL_assert(block_size_ok(bip->bp.ipl.bm_ptr.eckd.bptr.size),
  72                "Bad block size in zIPL section of the 1st record.");
  73 }
  74
  75 static block_number_t eckd_block_num(EckdCHS *chs)
  76 {
  77     const uint64_t sectors = virtio_get_sectors();
  78     const uint64_t heads = virtio_get_heads();
  79     const uint64_t cylinder = chs->cylinder
  80                             + ((chs->head & 0xfff0) << 12);
  81     const uint64_t head = chs->head & 0x000f;
  82     const block_number_t block = sectors * heads * cylinder
  83                                + sectors * head
  84                                + chs->sector
  85                                - 1; /* block nr starts with zero */
  86     return block;
  87 }
  88
  89 static bool eckd_valid_address(BootMapPointer *p)
  90 {
  91     const uint64_t head = p->eckd.chs.head & 0x000f;
  92
  93     if (head >= virtio_get_heads()
  94         ||  p->eckd.chs.sector > virtio_get_sectors()
  95         ||  p->eckd.chs.sector <= 0) {
  96         return false;
  97     }
  98
  99     if (!virtio_guessed_disk_nature() &&
 100         eckd_block_num(&p->eckd.chs) >= virtio_get_blocks()) {
 101         return false;
 102     }
 103
 104     return true;
 105 }
 106
 107 static block_number_t load_eckd_segments(block_number_t blk, uint64_t *address)
 108 {
 109     block_number_t block_nr;
 110     int j, rc;
 111     BootMapPointer *bprs = (void *)_bprs;
 112     bool more_data;
 113
 114     memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
 115     read_block(blk, bprs, "BPRS read failed");
 116
 117     do {
 118         more_data = false;
 119         for (j = 0;; j++) {
 120             block_nr = eckd_block_num(&bprs[j].xeckd.bptr.chs);
 121             if (is_null_block_number(block_nr)) { /* end of chunk */
 122                 break;
 123             }
 124
 125             /* we need the updated blockno for the next indirect entry
 126              * in the chain, but don't want to advance address
 127              */
 128             if (j == (max_bprs_entries - 1)) {
 129                 break;
 130             }
 131
 132             IPL_assert(block_size_ok(bprs[j].xeckd.bptr.size),
 133                        "bad chunk block size");
 134             IPL_assert(eckd_valid_address(&bprs[j]), "bad chunk ECKD addr");
 135
 136             if ((bprs[j].xeckd.bptr.count == 0) && unused_space(&(bprs[j+1]),
 137                 sizeof(EckdBlockPtr))) {
 138                 /* This is a "continue" pointer.
 139                  * This ptr should be the last one in the current
 140                  * script section.
 141                  * I.e. the next ptr must point to the unused memory area
 142                  */
 143                 memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
 144                 read_block(block_nr, bprs, "BPRS continuation read failed");
 145                 more_data = true;
 146                 break;
 147             }
 148
 149             /* Load (count+1) blocks of code at (block_nr)
 150              * to memory (address).
 151              */
 152             rc = virtio_read_many(block_nr, (void *)(*address),
 153                                   bprs[j].xeckd.bptr.count+1);
 154             IPL_assert(rc == 0, "code chunk read failed");
 155
 156             *address += (bprs[j].xeckd.bptr.count+1) * virtio_get_block_size();
 157         }
 158     } while (more_data);
 159     return block_nr;
 160 }
 161
 162 static bool find_zipl_boot_menu_banner(int *offset)
 163 {
 164     int i;
 165
 166     /* Menu banner starts with "zIPL" */
 167     for (i = 0; i <= virtio_get_block_size() - 4; i++) {
 168         if (magic_match(s2_cur_blk + i, ZIPL_MAGIC_EBCDIC)) {
 169             *offset = i;
 170             return true;
 171         }
 172     }
 173
 174     return false;
 175 }
 176
 177 static int eckd_get_boot_menu_index(block_number_t s1b_block_nr)
 178 {
 179     block_number_t cur_block_nr;
 180     block_number_t prev_block_nr = 0;
 181     block_number_t next_block_nr = 0;
 182     EckdStage1b *s1b = (void *)sec;
 183     int banner_offset;
 184     int i;
 185
 186     /* Get Stage1b data */
 187     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 188     read_block(s1b_block_nr, s1b, "Cannot read stage1b boot loader");
 189
 190     memset(_s2, FREE_SPACE_FILLER, sizeof(_s2));
 191
 192     /* Get Stage2 data */
 193     for (i = 0; i < STAGE2_BLK_CNT_MAX; i++) {
 194         cur_block_nr = eckd_block_num(&s1b->seek[i].chs);
 195
 196         if (!cur_block_nr || is_null_block_number(cur_block_nr)) {
 197             break;
 198         }
 199
 200         read_block(cur_block_nr, s2_cur_blk, "Cannot read stage2 boot loader");
 201
 202         if (find_zipl_boot_menu_banner(&banner_offset)) {
 203             /*
 204              * Load the adjacent blocks to account for the
 205              * possibility of menu data spanning multiple blocks.
 206              */
 207             if (prev_block_nr) {
 208                 read_block(prev_block_nr, s2_prev_blk,
 209                            "Cannot read stage2 boot loader");
 210             }
 211
 212             if (i + 1 < STAGE2_BLK_CNT_MAX) {
 213                 next_block_nr = eckd_block_num(&s1b->seek[i + 1].chs);
 214             }
 215
 216             if (next_block_nr && !is_null_block_number(next_block_nr)) {
 217                 read_block(next_block_nr, s2_next_blk,
 218                            "Cannot read stage2 boot loader");
 219             }
 220
 221             return menu_get_zipl_boot_index(s2_cur_blk + banner_offset);
 222         }
 223
 224         prev_block_nr = cur_block_nr;
 225     }
 226
 227     sclp_print("No zipl boot menu data found. Booting default entry.");
 228     return 0;
 229 }
 230
 231 static void run_eckd_boot_script(block_number_t bmt_block_nr,
 232                                  block_number_t s1b_block_nr)
 233 {
 234     int i;
 235     unsigned int loadparm = get_loadparm_index();
 236     block_number_t block_nr;
 237     uint64_t address;
 238     BootMapTable *bmt = (void *)sec;
 239     BootMapScript *bms = (void *)sec;
 240
 241     if (menu_is_enabled_zipl()) {
 242         loadparm = eckd_get_boot_menu_index(s1b_block_nr);
 243     }
 244
 245     debug_print_int("loadparm", loadparm);
 246     IPL_assert(loadparm < MAX_BOOT_ENTRIES, "loadparm value greater than"
 247                " maximum number of boot entries allowed");
 248
 249     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 250     read_block(bmt_block_nr, sec, "Cannot read Boot Map Table");
 251
 252     block_nr = eckd_block_num(&bmt->entry[loadparm].xeckd.bptr.chs);
 253     IPL_assert(block_nr != -1, "Cannot find Boot Map Table Entry");
 254
 255     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 256     read_block(block_nr, sec, "Cannot read Boot Map Script");
 257
 258     for (i = 0; bms->entry[i].type == BOOT_SCRIPT_LOAD ||
 259                 bms->entry[i].type == BOOT_SCRIPT_SIGNATURE; i++) {
 260
 261         /* We don't support secure boot yet, so we skip signature entries */
 262         if (bms->entry[i].type == BOOT_SCRIPT_SIGNATURE) {
 263             continue;
 264         }
 265
 266         address = bms->entry[i].address.load_address;
 267         block_nr = eckd_block_num(&bms->entry[i].blkptr.xeckd.bptr.chs);
 268
 269         do {
 270             block_nr = load_eckd_segments(block_nr, &address);
 271         } while (block_nr != -1);
 272     }
 273
 274     IPL_assert(bms->entry[i].type == BOOT_SCRIPT_EXEC,
 275                "Unknown script entry type");
 276     write_reset_psw(bms->entry[i].address.load_address); /* no return */
 277     jump_to_IPL_code(0); /* no return */
 278 }
 279
 280 static void ipl_eckd_cdl(void)
 281 {
 282     XEckdMbr *mbr;
 283     EckdCdlIpl2 *ipl2 = (void *)sec;
 284     IplVolumeLabel *vlbl = (void *)sec;
 285     block_number_t bmt_block_nr, s1b_block_nr;
 286
 287     /* we have just read the block #0 and recognized it as "IPL1" */
 288     sclp_print("CDL\n");
 289
 290     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 291     read_block(1, ipl2, "Cannot read IPL2 record at block 1");
 292
 293     mbr = &ipl2->mbr;
 294     if (!magic_match(mbr, ZIPL_MAGIC)) {
 295         sclp_print("No zIPL section in IPL2 record.\n");
 296         return;
 297     }
 298     if (!block_size_ok(mbr->blockptr.xeckd.bptr.size)) {
 299         sclp_print("Bad block size in zIPL section of IPL2 record.\n");
 300         return;
 301     }
 302     if (mbr->dev_type != DEV_TYPE_ECKD) {
 303         sclp_print("Non-ECKD device type in zIPL section of IPL2 record.\n");
 304         return;
 305     }
 306
 307     /* save pointer to Boot Map Table */
 308     bmt_block_nr = eckd_block_num(&mbr->blockptr.xeckd.bptr.chs);
 309
 310     /* save pointer to Stage1b Data */
 311     s1b_block_nr = eckd_block_num(&ipl2->stage1.seek[0].chs);
 312
 313     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 314     read_block(2, vlbl, "Cannot read Volume Label at block 2");
 315     if (!magic_match(vlbl->key, VOL1_MAGIC)) {
 316         sclp_print("Invalid magic of volume label block.\n");
 317         return;
 318     }
 319     if (!magic_match(vlbl->f.key, VOL1_MAGIC)) {
 320         sclp_print("Invalid magic of volser block.\n");
 321         return;
 322     }
 323     print_volser(vlbl->f.volser);
 324
 325     run_eckd_boot_script(bmt_block_nr, s1b_block_nr);
 326     /* no return */
 327 }
 328
 329 static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
 330 {
 331     LDL_VTOC *vlbl = (void *)sec; /* already read, 3rd block */
 332     char msg[4] = { '?', '.', '\n', '\0' };
 333
 334     sclp_print((mode == ECKD_CMS) ? "CMS" : "LDL");
 335     sclp_print(" version ");
 336     switch (vlbl->LDL_version) {
 337     case LDL1_VERSION:
 338         msg[0] = '1';
 339         break;
 340     case LDL2_VERSION:
 341         msg[0] = '2';
 342         break;
 343     default:
 344         msg[0] = ebc2asc[vlbl->LDL_version];
 345         msg[1] = '?';
 346         break;
 347     }
 348     sclp_print(msg);
 349     print_volser(vlbl->volser);
 350 }
 351
 352 static void ipl_eckd_ldl(ECKD_IPL_mode_t mode)
 353 {
 354     block_number_t bmt_block_nr, s1b_block_nr;
 355     EckdLdlIpl1 *ipl1 = (void *)sec;
 356
 357     if (mode != ECKD_LDL_UNLABELED) {
 358         print_eckd_ldl_msg(mode);
 359     }
 360
 361     /* DO NOT read BootMap pointer (only one, xECKD) at block #2 */
 362
 363     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 364     read_block(0, sec, "Cannot read block 0 to grab boot info.");
 365     if (mode == ECKD_LDL_UNLABELED) {
 366         if (!magic_match(ipl1->bip.magic, ZIPL_MAGIC)) {
 367             return; /* not applicable layout */
 368         }
 369         sclp_print("unlabeled LDL.\n");
 370     }
 371     verify_boot_info(&ipl1->bip);
 372
 373     /* save pointer to Boot Map Table */
 374     bmt_block_nr = eckd_block_num(&ipl1->bip.bp.ipl.bm_ptr.eckd.bptr.chs);
 375
 376     /* save pointer to Stage1b Data */
 377     s1b_block_nr = eckd_block_num(&ipl1->stage1.seek[0].chs);
 378
 379     run_eckd_boot_script(bmt_block_nr, s1b_block_nr);
 380     /* no return */
 381 }
 382
 383 static void print_eckd_msg(void)
 384 {
 385     char msg[] = "Using ECKD scheme (block size *****), ";
 386     char *p = &msg[34], *q = &msg[30];
 387     int n = virtio_get_block_size();
 388
 389     /* Fill in the block size and show up the message */
 390     if (n > 0 && n <= 99999) {
 391         while (n) {
 392             *p-- = '0' + (n % 10);
 393             n /= 10;
 394         }
 395         while (p >= q) {
 396             *p-- = ' ';
 397         }
 398     }
 399     sclp_print(msg);
 400 }
 401
 402 static void ipl_eckd(void)
 403 {
 404     XEckdMbr *mbr = (void *)sec;
 405     LDL_VTOC *vlbl = (void *)sec;
 406
 407     print_eckd_msg();
 408
 409     /* Grab the MBR again */
 410     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 411     read_block(0, mbr, "Cannot read block 0 on DASD");
 412
 413     if (magic_match(mbr->magic, IPL1_MAGIC)) {
 414         ipl_eckd_cdl();         /* only returns in case of error */
 415         return;
 416     }
 417
 418     /* LDL/CMS? */
 419     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 420     read_block(2, vlbl, "Cannot read block 2");
 421
 422     if (magic_match(vlbl->magic, CMS1_MAGIC)) {
 423         ipl_eckd_ldl(ECKD_CMS); /* no return */
 424     }
 425     if (magic_match(vlbl->magic, LNX1_MAGIC)) {
 426         ipl_eckd_ldl(ECKD_LDL); /* no return */
 427     }
 428
 429     ipl_eckd_ldl(ECKD_LDL_UNLABELED); /* it still may return */
 430     /*
 431      * Ok, it is not a LDL by any means.
 432      * It still might be a CDL with zero record keys for IPL1 and IPL2
 433      */
 434     ipl_eckd_cdl();
 435 }
 436
 437 /***********************************************************************
 438  * IPL a SCSI disk
 439  */
 440
 441 static void zipl_load_segment(ComponentEntry *entry)
 442 {
 443     const int max_entries = (MAX_SECTOR_SIZE / sizeof(ScsiBlockPtr));
 444     ScsiBlockPtr *bprs = (void *)sec;
 445     const int bprs_size = sizeof(sec);
 446     block_number_t blockno;
 447     uint64_t address;
 448     int i;
 449     char err_msg[] = "zIPL failed to read BPRS at 0xZZZZZZZZZZZZZZZZ";
 450     char *blk_no = &err_msg[30]; /* where to print blockno in (those ZZs) */
 451
 452     blockno = entry->data.blockno;
 453     address = entry->compdat.load_addr;
 454
 455     debug_print_int("loading segment at block", blockno);
 456     debug_print_int("addr", address);
 457
 458     do {
 459         memset(bprs, FREE_SPACE_FILLER, bprs_size);
 460         fill_hex_val(blk_no, &blockno, sizeof(blockno));
 461         read_block(blockno, bprs, err_msg);
 462
 463         for (i = 0;; i++) {
 464             uint64_t *cur_desc = (void *)&bprs[i];
 465
 466             blockno = bprs[i].blockno;
 467             if (!blockno) {
 468                 break;
 469             }
 470
 471             /* we need the updated blockno for the next indirect entry in the
 472                chain, but don't want to advance address */
 473             if (i == (max_entries - 1)) {
 474                 break;
 475             }
 476
 477             if (bprs[i].blockct == 0 && unused_space(&bprs[i + 1],
 478                 sizeof(ScsiBlockPtr))) {
 479                 /* This is a "continue" pointer.
 480                  * This ptr is the last one in the current script section.
 481                  * I.e. the next ptr must point to the unused memory area.
 482                  * The blockno is not zero, so the upper loop must continue
 483                  * reading next section of BPRS.
 484                  */
 485                 break;
 486             }
 487             address = virtio_load_direct(cur_desc[0], cur_desc[1], 0,
 488                                          (void *)address);
 489             IPL_assert(address != -1, "zIPL load segment failed");
 490         }
 491     } while (blockno);
 492 }
 493
 494 /* Run a zipl program */
 495 static void zipl_run(ScsiBlockPtr *pte)
 496 {
 497     ComponentHeader *header;
 498     ComponentEntry *entry;
 499     uint8_t tmp_sec[MAX_SECTOR_SIZE];
 500
 501     read_block(pte->blockno, tmp_sec, "Cannot read header");
 502     header = (ComponentHeader *)tmp_sec;
 503
 504     IPL_assert(magic_match(tmp_sec, ZIPL_MAGIC), "No zIPL magic in header");
 505     IPL_assert(header->type == ZIPL_COMP_HEADER_IPL, "Bad header type");
 506
 507     dputs("start loading images\n");
 508
 509     /* Load image(s) into RAM */
 510     entry = (ComponentEntry *)(&header[1]);
 511     while (entry->component_type == ZIPL_COMP_ENTRY_LOAD ||
 512            entry->component_type == ZIPL_COMP_ENTRY_SIGNATURE) {
 513
 514         /* We don't support secure boot yet, so we skip signature entries */
 515         if (entry->component_type == ZIPL_COMP_ENTRY_SIGNATURE) {
 516             entry++;
 517             continue;
 518         }
 519
 520         zipl_load_segment(entry);
 521
 522         entry++;
 523
 524         IPL_assert((uint8_t *)(&entry[1]) <= (tmp_sec + MAX_SECTOR_SIZE),
 525                    "Wrong entry value");
 526     }
 527
 528     IPL_assert(entry->component_type == ZIPL_COMP_ENTRY_EXEC, "No EXEC entry");
 529
 530     /* should not return */
 531     write_reset_psw(entry->compdat.load_psw);
 532     jump_to_IPL_code(0);
 533 }
 534
 535 static void ipl_scsi(void)
 536 {
 537     ScsiMbr *mbr = (void *)sec;
 538     int program_table_entries = 0;
 539     BootMapTable *prog_table = (void *)sec;
 540     unsigned int loadparm = get_loadparm_index();
 541     bool valid_entries[MAX_BOOT_ENTRIES] = {false};
 542     size_t i;
 543
 544     /* Grab the MBR */
 545     memset(sec, FREE_SPACE_FILLER, sizeof(sec));
 546     read_block(0, mbr, "Cannot read block 0");
 547
 548     if (!magic_match(mbr->magic, ZIPL_MAGIC)) {
 549         return;
 550     }
 551
 552     sclp_print("Using SCSI scheme.\n");
 553     debug_print_int("MBR Version", mbr->version_id);
 554     IPL_check(mbr->version_id == 1,
 555               "Unknown MBR layout version, assuming version 1");
 556     debug_print_int("program table", mbr->pt.blockno);
 557     IPL_assert(mbr->pt.blockno, "No Program Table");
 558
 559     /* Parse the program table */
 560     read_block(mbr->pt.blockno, sec, "Error reading Program Table");
 561     IPL_assert(magic_match(sec, ZIPL_MAGIC), "No zIPL magic in PT");
 562
 563     for (i = 0; i < MAX_BOOT_ENTRIES; i++) {
 564         if (prog_table->entry[i].scsi.blockno) {
 565             valid_entries[i] = true;
 566             program_table_entries++;
 567         }
 568     }
 569
 570     debug_print_int("program table entries", program_table_entries);
 571     IPL_assert(program_table_entries != 0, "Empty Program Table");
 572
 573     if (menu_is_enabled_enum()) {
 574         loadparm = menu_get_enum_boot_index(valid_entries);
 575     }
 576
 577     debug_print_int("loadparm", loadparm);
 578     IPL_assert(loadparm < MAX_BOOT_ENTRIES, "loadparm value greater than"
 579                " maximum number of boot entries allowed");
 580
 581     zipl_run(&prog_table->entry[loadparm].scsi); /* no return */
 582 }
 583
 584 /***********************************************************************
 585  * IPL El Torito ISO9660 image or DVD
 586  */
 587
 588 static bool is_iso_bc_entry_compatible(IsoBcSection *s)
 589 {
 590     uint8_t *magic_sec = (uint8_t *)(sec + ISO_SECTOR_SIZE);
 591
 592     if (s->unused || !s->sector_count) {
 593         return false;
 594     }
 595     read_iso_sector(bswap32(s->load_rba), magic_sec,
 596                     "Failed to read image sector 0");
 597
 598     /* Checking bytes 8 - 32 for S390 Linux magic */
 599     return !memcmp(magic_sec + 8, linux_s390_magic, 24);
 600 }
 601
 602 /* Location of the current sector of the directory */
 603 static uint32_t sec_loc[ISO9660_MAX_DIR_DEPTH];
 604 /* Offset in the current sector of the directory */
 605 static uint32_t sec_offset[ISO9660_MAX_DIR_DEPTH];
 606 /* Remained directory space in bytes */
 607 static uint32_t dir_rem[ISO9660_MAX_DIR_DEPTH];
 608
 609 static inline uint32_t iso_get_file_size(uint32_t load_rba)
 610 {
 611     IsoVolDesc *vd = (IsoVolDesc *)sec;
 612     IsoDirHdr *cur_record = &vd->vd.primary.rootdir;
 613     uint8_t *temp = sec + ISO_SECTOR_SIZE;
 614     int level = 0;
 615
 616     read_iso_sector(ISO_PRIMARY_VD_SECTOR, sec,
 617                     "Failed to read ISO primary descriptor");
 618     sec_loc[0] = iso_733_to_u32(cur_record->ext_loc);
 619     dir_rem[0] = 0;
 620     sec_offset[0] = 0;
 621
 622     while (level >= 0) {
 623         IPL_assert(sec_offset[level] <= ISO_SECTOR_SIZE,
 624                    "Directory tree structure violation");
 625
 626         cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
 627
 628         if (sec_offset[level] == 0) {
 629             read_iso_sector(sec_loc[level], temp,
 630                             "Failed to read ISO directory");
 631             if (dir_rem[level] == 0) {
 632                 /* Skip self and parent records */
 633                 dir_rem[level] = iso_733_to_u32(cur_record->data_len) -
 634                                  cur_record->dr_len;
 635                 sec_offset[level] += cur_record->dr_len;
 636
 637                 cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
 638                 dir_rem[level] -= cur_record->dr_len;
 639                 sec_offset[level] += cur_record->dr_len;
 640                 continue;
 641             }
 642         }
 643
 644         if (!cur_record->dr_len || sec_offset[level] == ISO_SECTOR_SIZE) {
 645             /* Zero-padding and/or the end of current sector */
 646             dir_rem[level] -= ISO_SECTOR_SIZE - sec_offset[level];
 647             sec_offset[level] = 0;
 648             sec_loc[level]++;
 649         } else {
 650             /* The directory record is valid */
 651             if (load_rba == iso_733_to_u32(cur_record->ext_loc)) {
 652                 return iso_733_to_u32(cur_record->data_len);
 653             }
 654
 655             dir_rem[level] -= cur_record->dr_len;
 656             sec_offset[level] += cur_record->dr_len;
 657
 658             if (cur_record->file_flags & 0x2) {
 659                 /* Subdirectory */
 660                 if (level == ISO9660_MAX_DIR_DEPTH - 1) {
 661                     sclp_print("ISO-9660 directory depth limit exceeded\n");
 662                 } else {
 663                     level++;
 664                     sec_loc[level] = iso_733_to_u32(cur_record->ext_loc);
 665                     sec_offset[level] = 0;
 666                     dir_rem[level] = 0;
 667                     continue;
 668                 }
 669             }
 670         }
 671
 672         if (dir_rem[level] == 0) {
 673             /* Nothing remaining */
 674             level--;
 675             read_iso_sector(sec_loc[level], temp,
 676                             "Failed to read ISO directory");
 677         }
 678     }
 679
 680     return 0;
 681 }
 682
 683 static void load_iso_bc_entry(IsoBcSection *load)
 684 {
 685     IsoBcSection s = *load;
 686     /*
 687      * According to spec, extent for each file
 688      * is padded and ISO_SECTOR_SIZE bytes aligned
 689      */
 690     uint32_t blks_to_load = bswap16(s.sector_count) >> ET_SECTOR_SHIFT;
 691     uint32_t real_size = iso_get_file_size(bswap32(s.load_rba));
 692
 693     if (real_size) {
 694         /* Round up blocks to load */
 695         blks_to_load = (real_size + ISO_SECTOR_SIZE - 1) / ISO_SECTOR_SIZE;
 696         sclp_print("ISO boot image size verified\n");
 697     } else {
 698         sclp_print("ISO boot image size could not be verified\n");
 699     }
 700
 701     read_iso_boot_image(bswap32(s.load_rba),
 702                         (void *)((uint64_t)bswap16(s.load_segment)),
 703                         blks_to_load);
 704
 705     jump_to_low_kernel();
 706 }
 707
 708 static uint32_t find_iso_bc(void)
 709 {
 710     IsoVolDesc *vd = (IsoVolDesc *)sec;
 711     uint32_t block_num = ISO_PRIMARY_VD_SECTOR;
 712
 713     if (virtio_read_many(block_num++, sec, 1)) {
 714         /* If primary vd cannot be read, there is no boot catalog */
 715         return 0;
 716     }
 717
 718     while (is_iso_vd_valid(vd) && vd->type != VOL_DESC_TERMINATOR) {
 719         if (vd->type == VOL_DESC_TYPE_BOOT) {
 720             IsoVdElTorito *et = &vd->vd.boot;
 721
 722             if (!memcmp(&et->el_torito[0], el_torito_magic, 32)) {
 723                 return bswap32(et->bc_offset);
 724             }
 725         }
 726         read_iso_sector(block_num++, sec,
 727                         "Failed to read ISO volume descriptor");
 728     }
 729
 730     return 0;
 731 }
 732
 733 static IsoBcSection *find_iso_bc_entry(void)
 734 {
 735     IsoBcEntry *e = (IsoBcEntry *)sec;
 736     uint32_t offset = find_iso_bc();
 737     int i;
 738     unsigned int loadparm = get_loadparm_index();
 739
 740     if (!offset) {
 741         return NULL;
 742     }
 743
 744     read_iso_sector(offset, sec, "Failed to read El Torito boot catalog");
 745
 746     if (!is_iso_bc_valid(e)) {
 747         /* The validation entry is mandatory */
 748         panic("No valid boot catalog found!\n");
 749         return NULL;
 750     }
 751
 752     /*
 753      * Each entry has 32 bytes size, so one sector cannot contain > 64 entries.
 754      * We consider only boot catalogs with no more than 64 entries.
 755      */
 756     for (i = 1; i < ISO_BC_ENTRY_PER_SECTOR; i++) {
 757         if (e[i].id == ISO_BC_BOOTABLE_SECTION) {
 758             if (is_iso_bc_entry_compatible(&e[i].body.sect)) {
 759                 if (loadparm <= 1) {
 760                     /* found, default, or unspecified */
 761                     return &e[i].body.sect;
 762                 }
 763                 loadparm--;
 764             }
 765         }
 766     }
 767
 768     panic("No suitable boot entry found on ISO-9660 media!\n");
 769
 770     return NULL;
 771 }
 772
 773 static void ipl_iso_el_torito(void)
 774 {
 775     IsoBcSection *s = find_iso_bc_entry();
 776
 777     if (s) {
 778         load_iso_bc_entry(s);
 779         /* no return */
 780     }
 781 }
 782
 783 /***********************************************************************
 784  * Bus specific IPL sequences
 785  */
 786
 787 static void zipl_load_vblk(void)
 788 {
 789     if (virtio_guessed_disk_nature()) {
 790         virtio_assume_iso9660();
 791     }
 792     ipl_iso_el_torito();
 793
 794     if (virtio_guessed_disk_nature()) {
 795         sclp_print("Using guessed DASD geometry.\n");
 796         virtio_assume_eckd();
 797     }
 798     ipl_eckd();
 799 }
 800
 801 static void zipl_load_vscsi(void)
 802 {
 803     if (virtio_get_block_size() == VIRTIO_ISO_BLOCK_SIZE) {
 804         /* Is it an ISO image in non-CD drive? */
 805         ipl_iso_el_torito();
 806     }
 807
 808     sclp_print("Using guessed DASD geometry.\n");
 809     virtio_assume_eckd();
 810     ipl_eckd();
 811 }
 812
 813 /***********************************************************************
 814  * IPL starts here
 815  */
 816
 817 void zipl_load(void)
 818 {
 819     VDev *vdev = virtio_get_device();
 820
 821     if (vdev->is_cdrom) {
 822         ipl_iso_el_torito();
 823         panic("\n! Cannot IPL this ISO image !\n");
 824     }
 825
 826     if (virtio_get_device_type() == VIRTIO_ID_NET) {
 827         jump_to_IPL_code(vdev->netboot_start_addr);
 828     }
 829
 830     ipl_scsi();
 831
 832     switch (virtio_get_device_type()) {
 833     case VIRTIO_ID_BLOCK:
 834         zipl_load_vblk();
 835         break;
 836     case VIRTIO_ID_SCSI:
 837         zipl_load_vscsi();
 838         break;
 839     default:
 840         panic("\n! Unknown IPL device type !\n");
 841     }
 842
 843     sclp_print("zIPL load failed.\n");
 844 }