1 /* 2 * GRUB -- GRand Unified Bootloader 3 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 */ 19 /* 20 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 21 * Use is subject to license terms. 22 */ 23 #pragma ident "%Z%%M% %I% %E% SMI" 24 25 /* 26 * The zfs plug-in routines for GRUB are: 27 * 28 * zfs_mount() - locates a valid uberblock of the root pool and reads 29 * in its MOS at the memory address MOS. 30 * 31 * zfs_open() - locates a plain file object by following the MOS 32 * and places its dnode at the memory address DNODE. 33 * 34 * zfs_read() - read in the data blocks pointed by the DNODE. 35 * 36 * ZFS_SCRATCH is used as a working area. 37 * 38 * (memory addr) MOS DNODE ZFS_SCRATCH 39 * | | | 40 * +-------V---------V----------V---------------+ 41 * memory | | dnode | dnode | scratch | 42 * | | 512B | 512B | area | 43 * +--------------------------------------------+ 44 */ 45 46 #ifdef FSYS_ZFS 47 48 #include "shared.h" 49 #include "filesys.h" 50 #include "fsys_zfs.h" 51 52 /* cache for a file block of the currently zfs_open()-ed file */ 53 static void *file_buf = NULL; 54 static uint64_t file_start = 0; 55 static uint64_t file_end = 0; 56 57 /* cache for a dnode block */ 58 static dnode_phys_t *dnode_buf = NULL; 59 static dnode_phys_t *dnode_mdn = NULL; 60 static uint64_t dnode_start = 0; 61 static uint64_t dnode_end = 0; 62 63 static uberblock_t current_uberblock; 64 65 static char *stackbase; 66 67 decomp_entry_t decomp_table[ZIO_COMPRESS_FUNCTIONS] = 68 { 69 {"inherit", 0}, /* ZIO_COMPRESS_INHERIT */ 70 {"on", lzjb_decompress}, /* ZIO_COMPRESS_ON */ 71 {"off", 0}, /* ZIO_COMPRESS_OFF */ 72 {"lzjb", lzjb_decompress}, /* ZIO_COMPRESS_LZJB */ 73 {"empty", 0} /* ZIO_COMPRESS_EMPTY */ 74 }; 75 76 /* 77 * Our own version of bcmp(). 78 */ 79 static int 80 zfs_bcmp(const void *s1, const void *s2, size_t n) 81 { 82 const uchar_t *ps1 = s1; 83 const uchar_t *ps2 = s2; 84 85 if (s1 != s2 && n != 0) { 86 do { 87 if (*ps1++ != *ps2++) 88 return (1); 89 } while (--n != 0); 90 } 91 92 return (0); 93 } 94 95 /* 96 * Our own version of log2(). Same thing as highbit()-1. 97 */ 98 static int 99 zfs_log2(uint64_t num) 100 { 101 int i = 0; 102 103 while (num > 1) { 104 i++; 105 num = num >> 1; 106 } 107 108 return (i); 109 } 110 111 /* Checksum Functions */ 112 static void 113 zio_checksum_off(const void *buf, uint64_t size, zio_cksum_t *zcp) 114 { 115 ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); 116 } 117 118 /* Checksum Table and Values */ 119 zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = { 120 NULL, NULL, 0, 0, "inherit", 121 NULL, NULL, 0, 0, "on", 122 zio_checksum_off, zio_checksum_off, 0, 0, "off", 123 zio_checksum_SHA256, zio_checksum_SHA256, 1, 1, "label", 124 zio_checksum_SHA256, zio_checksum_SHA256, 1, 1, "gang_header", 125 fletcher_2_native, fletcher_2_byteswap, 0, 1, "zilog", 126 fletcher_2_native, fletcher_2_byteswap, 0, 0, "fletcher2", 127 fletcher_4_native, fletcher_4_byteswap, 1, 0, "fletcher4", 128 zio_checksum_SHA256, zio_checksum_SHA256, 1, 0, "SHA256", 129 }; 130 131 /* 132 * zio_checksum_verify: Provides support for checksum verification. 133 * 134 * Fletcher2, Fletcher4, and SHA256 are supported. 135 * 136 * Return: 137 * -1 = Failure 138 * 0 = Success 139 */ 140 static int 141 zio_checksum_verify(blkptr_t *bp, char *data, int size) 142 { 143 zio_cksum_t zc = bp->blk_cksum; 144 uint32_t checksum = BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : 145 BP_GET_CHECKSUM(bp); 146 int byteswap = BP_SHOULD_BYTESWAP(bp); 147 zio_block_tail_t *zbt = (zio_block_tail_t *)(data + size) - 1; 148 zio_checksum_info_t *ci = &zio_checksum_table[checksum]; 149 zio_cksum_t actual_cksum, expected_cksum; 150 151 /* byteswap is not supported */ 152 if (byteswap) 153 return (-1); 154 155 if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL) 156 return (-1); 157 158 if (ci->ci_zbt) { 159 if (checksum == ZIO_CHECKSUM_GANG_HEADER) { 160 /* 161 * 'gang blocks' is not supported. 162 */ 163 return (-1); 164 } 165 166 if (zbt->zbt_magic == BSWAP_64(ZBT_MAGIC)) { 167 /* byte swapping is not supported */ 168 return (-1); 169 } else { 170 expected_cksum = zbt->zbt_cksum; 171 zbt->zbt_cksum = zc; 172 ci->ci_func[0](data, size, &actual_cksum); 173 zbt->zbt_cksum = expected_cksum; 174 } 175 zc = expected_cksum; 176 177 } else { 178 if (BP_IS_GANG(bp)) 179 return (-1); 180 ci->ci_func[byteswap](data, size, &actual_cksum); 181 } 182 183 if ((actual_cksum.zc_word[0] - zc.zc_word[0]) | 184 (actual_cksum.zc_word[1] - zc.zc_word[1]) | 185 (actual_cksum.zc_word[2] - zc.zc_word[2]) | 186 (actual_cksum.zc_word[3] - zc.zc_word[3])) 187 return (-1); 188 189 return (0); 190 } 191 192 /* 193 * vdev_label_offset takes "offset" (the offset within a vdev_label) and 194 * returns its physical disk offset (starting from the beginning of the vdev). 195 * 196 * Input: 197 * psize : Physical size of this vdev 198 * l : Label Number (0-3) 199 * offset : The offset with a vdev_label in which we want the physical 200 * address 201 * Return: 202 * Success : physical disk offset 203 * Failure : errnum = ERR_BAD_ARGUMENT, return value is meaningless 204 */ 205 static uint64_t 206 vdev_label_offset(uint64_t psize, int l, uint64_t offset) 207 { 208 /* XXX Need to add back label support! */ 209 if (l >= VDEV_LABELS/2 || offset > sizeof (vdev_label_t)) { 210 errnum = ERR_BAD_ARGUMENT; 211 return (0); 212 } 213 214 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 215 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 216 217 } 218 219 /* 220 * vdev_uberblock_compare takes two uberblock structures and returns an integer 221 * indicating the more recent of the two. 222 * Return Value = 1 if ub2 is more recent 223 * Return Value = -1 if ub1 is more recent 224 * The most recent uberblock is determined using its transaction number and 225 * timestamp. The uberblock with the highest transaction number is 226 * considered "newer". If the transaction numbers of the two blocks match, the 227 * timestamps are compared to determine the "newer" of the two. 228 */ 229 static int 230 vdev_uberblock_compare(uberblock_t *ub1, uberblock_t *ub2) 231 { 232 if (ub1->ub_txg < ub2->ub_txg) 233 return (-1); 234 if (ub1->ub_txg > ub2->ub_txg) 235 return (1); 236 237 if (ub1->ub_timestamp < ub2->ub_timestamp) 238 return (-1); 239 if (ub1->ub_timestamp > ub2->ub_timestamp) 240 return (1); 241 242 return (0); 243 } 244 245 /* 246 * Three pieces of information are needed to verify an uberblock: the magic 247 * number, the version number, and the checksum. 248 * 249 * Currently Implemented: version number, magic number 250 * Need to Implement: checksum 251 * 252 * Return: 253 * 0 - Success 254 * -1 - Failure 255 */ 256 static int 257 uberblock_verify(uberblock_phys_t *ub, int offset) 258 { 259 260 uberblock_t *uber = &ub->ubp_uberblock; 261 blkptr_t bp; 262 263 BP_ZERO(&bp); 264 BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL); 265 BP_SET_BYTEORDER(&bp, ZFS_HOST_BYTEORDER); 266 ZIO_SET_CHECKSUM(&bp.blk_cksum, offset, 0, 0, 0); 267 268 if (zio_checksum_verify(&bp, (char *)ub, UBERBLOCK_SIZE) != 0) 269 return (-1); 270 271 if (uber->ub_magic == UBERBLOCK_MAGIC && 272 uber->ub_version > 0 && uber->ub_version <= SPA_VERSION) 273 return (0); 274 275 return (-1); 276 } 277 278 /* 279 * Find the best uberblock. 280 * Return: 281 * Success - Pointer to the best uberblock. 282 * Failure - NULL 283 */ 284 static uberblock_phys_t * 285 find_bestub(uberblock_phys_t *ub_array, int label) 286 { 287 uberblock_phys_t *ubbest = NULL; 288 int i, offset; 289 290 for (i = 0; i < (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT); i++) { 291 offset = vdev_label_offset(0, label, VDEV_UBERBLOCK_OFFSET(i)); 292 if (errnum == ERR_BAD_ARGUMENT) 293 return (NULL); 294 if (uberblock_verify(&ub_array[i], offset) == 0) { 295 if (ubbest == NULL) { 296 ubbest = &ub_array[i]; 297 } else if (vdev_uberblock_compare( 298 &(ub_array[i].ubp_uberblock), 299 &(ubbest->ubp_uberblock)) > 0) { 300 ubbest = &ub_array[i]; 301 } 302 } 303 } 304 305 return (ubbest); 306 } 307 308 /* 309 * Read in a block and put its uncompressed data in buf. 310 * 311 * Return: 312 * 0 - success 313 * errnum - failure 314 */ 315 static int 316 zio_read(blkptr_t *bp, void *buf, char *stack) 317 { 318 uint64_t offset, sector; 319 int psize, lsize; 320 int i, comp, cksum; 321 322 psize = BP_GET_PSIZE(bp); 323 lsize = BP_GET_LSIZE(bp); 324 comp = BP_GET_COMPRESS(bp); 325 cksum = BP_GET_CHECKSUM(bp); 326 327 if ((unsigned int)comp >= ZIO_COMPRESS_FUNCTIONS || 328 comp != ZIO_COMPRESS_OFF && decomp_table[comp].decomp_func == NULL) 329 return (ERR_FSYS_CORRUPT); 330 331 if ((char *)buf < stack && ((char *)buf) + lsize > stack) 332 return (ERR_FSYS_CORRUPT); 333 /* pick a good dva from the block pointer */ 334 for (i = 0; i < SPA_DVAS_PER_BP; i++) { 335 336 if (bp->blk_dva[i].dva_word[0] == 0 && 337 bp->blk_dva[i].dva_word[1] == 0) 338 continue; 339 340 /* read in a block */ 341 offset = DVA_GET_OFFSET(&bp->blk_dva[i]); 342 sector = DVA_OFFSET_TO_PHYS_SECTOR(offset); 343 344 if (comp != ZIO_COMPRESS_OFF) { 345 346 if (devread(sector, 0, psize, stack) == 0) 347 continue; 348 if (zio_checksum_verify(bp, stack, psize) != 0) 349 continue; 350 decomp_table[comp].decomp_func(stack, buf, psize, 351 lsize); 352 } else { 353 if (devread(sector, 0, psize, buf) == 0) 354 continue; 355 if (zio_checksum_verify(bp, buf, psize) != 0) 356 continue; 357 } 358 return (0); 359 } 360 361 return (ERR_FSYS_CORRUPT); 362 } 363 364 /* 365 * Get the block from a block id. 366 * push the block onto the stack. 367 * 368 * Return: 369 * 0 - success 370 * errnum - failure 371 */ 372 static int 373 dmu_read(dnode_phys_t *dn, uint64_t blkid, void *buf, char *stack) 374 { 375 int idx, level; 376 blkptr_t *bp_array = dn->dn_blkptr; 377 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 378 blkptr_t *bp, *tmpbuf; 379 380 bp = (blkptr_t *)stack; 381 stack += sizeof (blkptr_t); 382 383 tmpbuf = (blkptr_t *)stack; 384 stack += 1<<dn->dn_indblkshift; 385 386 for (level = dn->dn_nlevels - 1; level >= 0; level--) { 387 idx = (blkid >> (epbs * level)) & ((1<<epbs)-1); 388 *bp = bp_array[idx]; 389 if (level == 0) 390 tmpbuf = buf; 391 if (BP_IS_HOLE(bp)) { 392 grub_memset(buf, 0, 393 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 394 break; 395 } else if (errnum = zio_read(bp, tmpbuf, stack)) { 396 return (errnum); 397 } 398 399 bp_array = tmpbuf; 400 } 401 402 return (0); 403 } 404 405 /* 406 * mzap_lookup: Looks up property described by "name" and returns the value 407 * in "value". 408 * 409 * Return: 410 * 0 - success 411 * errnum - failure 412 */ 413 static int 414 mzap_lookup(mzap_phys_t *zapobj, int objsize, char *name, 415 uint64_t *value) 416 { 417 int i, chunks; 418 mzap_ent_phys_t *mzap_ent = zapobj->mz_chunk; 419 420 chunks = objsize/MZAP_ENT_LEN - 1; 421 for (i = 0; i < chunks; i++) { 422 if (grub_strcmp(mzap_ent[i].mze_name, name) == 0) { 423 *value = mzap_ent[i].mze_value; 424 return (0); 425 } 426 } 427 428 return (ERR_FSYS_CORRUPT); 429 } 430 431 static uint64_t 432 zap_hash(uint64_t salt, const char *name) 433 { 434 static uint64_t table[256]; 435 const uint8_t *cp; 436 uint8_t c; 437 uint64_t crc = salt; 438 439 if (table[128] == 0) { 440 uint64_t *ct; 441 int i, j; 442 for (i = 0; i < 256; i++) { 443 for (ct = table + i, *ct = i, j = 8; j > 0; j--) 444 *ct = (*ct >> 1) ^ (-(*ct & 1) & 445 ZFS_CRC64_POLY); 446 } 447 } 448 449 if (crc == 0 || table[128] != ZFS_CRC64_POLY) { 450 errnum = ERR_FSYS_CORRUPT; 451 return (0); 452 } 453 454 for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++) 455 crc = (crc >> 8) ^ table[(crc ^ c) & 0xFF]; 456 457 /* 458 * Only use 28 bits, since we need 4 bits in the cookie for the 459 * collision differentiator. We MUST use the high bits, since 460 * those are the onces that we first pay attention to when 461 * chosing the bucket. 462 */ 463 crc &= ~((1ULL << (64 - ZAP_HASHBITS)) - 1); 464 465 return (crc); 466 } 467 468 /* 469 * Only to be used on 8-bit arrays. 470 * array_len is actual len in bytes (not encoded le_value_length). 471 * buf is null-terminated. 472 */ 473 static int 474 zap_leaf_array_equal(zap_leaf_phys_t *l, int blksft, int chunk, 475 int array_len, const char *buf) 476 { 477 int bseen = 0; 478 479 while (bseen < array_len) { 480 struct zap_leaf_array *la = 481 &ZAP_LEAF_CHUNK(l, blksft, chunk).l_array; 482 int toread = MIN(array_len - bseen, ZAP_LEAF_ARRAY_BYTES); 483 484 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 485 return (0); 486 487 if (zfs_bcmp(la->la_array, buf + bseen, toread) != 0) 488 break; 489 chunk = la->la_next; 490 bseen += toread; 491 } 492 return (bseen == array_len); 493 } 494 495 /* 496 * Given a zap_leaf_phys_t, walk thru the zap leaf chunks to get the 497 * value for the property "name". 498 * 499 * Return: 500 * 0 - success 501 * errnum - failure 502 */ 503 static int 504 zap_leaf_lookup(zap_leaf_phys_t *l, int blksft, uint64_t h, 505 const char *name, uint64_t *value) 506 { 507 uint16_t chunk; 508 struct zap_leaf_entry *le; 509 510 /* Verify if this is a valid leaf block */ 511 if (l->l_hdr.lh_block_type != ZBT_LEAF) 512 return (ERR_FSYS_CORRUPT); 513 if (l->l_hdr.lh_magic != ZAP_LEAF_MAGIC) 514 return (ERR_FSYS_CORRUPT); 515 516 for (chunk = l->l_hash[LEAF_HASH(blksft, h)]; 517 chunk != CHAIN_END; chunk = le->le_next) { 518 519 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 520 return (ERR_FSYS_CORRUPT); 521 522 le = ZAP_LEAF_ENTRY(l, blksft, chunk); 523 524 /* Verify the chunk entry */ 525 if (le->le_type != ZAP_CHUNK_ENTRY) 526 return (ERR_FSYS_CORRUPT); 527 528 if (le->le_hash != h) 529 continue; 530 531 if (zap_leaf_array_equal(l, blksft, le->le_name_chunk, 532 le->le_name_length, name)) { 533 534 struct zap_leaf_array *la; 535 uint8_t *ip; 536 537 if (le->le_int_size != 8 || le->le_value_length != 1) 538 return (ERR_FSYS_CORRUPT); 539 540 /* get the uint64_t property value */ 541 la = &ZAP_LEAF_CHUNK(l, blksft, 542 le->le_value_chunk).l_array; 543 ip = la->la_array; 544 545 *value = (uint64_t)ip[0] << 56 | (uint64_t)ip[1] << 48 | 546 (uint64_t)ip[2] << 40 | (uint64_t)ip[3] << 32 | 547 (uint64_t)ip[4] << 24 | (uint64_t)ip[5] << 16 | 548 (uint64_t)ip[6] << 8 | (uint64_t)ip[7]; 549 550 return (0); 551 } 552 } 553 554 return (ERR_FSYS_CORRUPT); 555 } 556 557 /* 558 * Fat ZAP lookup 559 * 560 * Return: 561 * 0 - success 562 * errnum - failure 563 */ 564 static int 565 fzap_lookup(dnode_phys_t *zap_dnode, zap_phys_t *zap, 566 char *name, uint64_t *value, char *stack) 567 { 568 zap_leaf_phys_t *l; 569 uint64_t hash, idx, blkid; 570 int blksft = zfs_log2(zap_dnode->dn_datablkszsec << DNODE_SHIFT); 571 572 /* Verify if this is a fat zap header block */ 573 if (zap->zap_magic != (uint64_t)ZAP_MAGIC) 574 return (ERR_FSYS_CORRUPT); 575 576 hash = zap_hash(zap->zap_salt, name); 577 if (errnum) 578 return (errnum); 579 580 /* get block id from index */ 581 if (zap->zap_ptrtbl.zt_numblks != 0) { 582 /* external pointer tables not supported */ 583 return (ERR_FSYS_CORRUPT); 584 } 585 idx = ZAP_HASH_IDX(hash, zap->zap_ptrtbl.zt_shift); 586 blkid = ((uint64_t *)zap)[idx + (1<<(blksft-3-1))]; 587 588 /* Get the leaf block */ 589 l = (zap_leaf_phys_t *)stack; 590 stack += 1<<blksft; 591 if ((1<<blksft) < sizeof (zap_leaf_phys_t)) 592 return (ERR_FSYS_CORRUPT); 593 if (errnum = dmu_read(zap_dnode, blkid, l, stack)) 594 return (errnum); 595 596 return (zap_leaf_lookup(l, blksft, hash, name, value)); 597 } 598 599 /* 600 * Read in the data of a zap object and find the value for a matching 601 * property name. 602 * 603 * Return: 604 * 0 - success 605 * errnum - failure 606 */ 607 static int 608 zap_lookup(dnode_phys_t *zap_dnode, char *name, uint64_t *val, char *stack) 609 { 610 uint64_t block_type; 611 int size; 612 void *zapbuf; 613 614 /* Read in the first block of the zap object data. */ 615 zapbuf = stack; 616 size = zap_dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT; 617 stack += size; 618 if (errnum = dmu_read(zap_dnode, 0, zapbuf, stack)) 619 return (errnum); 620 621 block_type = *((uint64_t *)zapbuf); 622 623 if (block_type == ZBT_MICRO) { 624 return (mzap_lookup(zapbuf, size, name, val)); 625 } else if (block_type == ZBT_HEADER) { 626 /* this is a fat zap */ 627 return (fzap_lookup(zap_dnode, zapbuf, name, 628 val, stack)); 629 } 630 631 return (ERR_FSYS_CORRUPT); 632 } 633 634 /* 635 * Get the dnode of an object number from the metadnode of an object set. 636 * 637 * Input 638 * mdn - metadnode to get the object dnode 639 * objnum - object number for the object dnode 640 * buf - data buffer that holds the returning dnode 641 * stack - scratch area 642 * 643 * Return: 644 * 0 - success 645 * errnum - failure 646 */ 647 static int 648 dnode_get(dnode_phys_t *mdn, uint64_t objnum, uint8_t type, dnode_phys_t *buf, 649 char *stack) 650 { 651 uint64_t blkid, blksz; /* the block id this object dnode is in */ 652 int epbs; /* shift of number of dnodes in a block */ 653 int idx; /* index within a block */ 654 dnode_phys_t *dnbuf; 655 656 blksz = mdn->dn_datablkszsec << SPA_MINBLOCKSHIFT; 657 epbs = zfs_log2(blksz) - DNODE_SHIFT; 658 blkid = objnum >> epbs; 659 idx = objnum & ((1<<epbs)-1); 660 661 if (dnode_buf != NULL && dnode_mdn == mdn && 662 objnum >= dnode_start && objnum < dnode_end) { 663 grub_memmove(buf, &dnode_buf[idx], DNODE_SIZE); 664 VERIFY_DN_TYPE(buf, type); 665 return (0); 666 } 667 668 if (dnode_buf && blksz == 1<<DNODE_BLOCK_SHIFT) { 669 dnbuf = dnode_buf; 670 dnode_mdn = mdn; 671 dnode_start = blkid << epbs; 672 dnode_end = (blkid + 1) << epbs; 673 } else { 674 dnbuf = (dnode_phys_t *)stack; 675 stack += blksz; 676 } 677 678 if (errnum = dmu_read(mdn, blkid, (char *)dnbuf, stack)) 679 return (errnum); 680 681 grub_memmove(buf, &dnbuf[idx], DNODE_SIZE); 682 VERIFY_DN_TYPE(buf, type); 683 684 return (0); 685 } 686 687 /* 688 * Check if this is a special file that resides at the top 689 * dataset of the pool. Currently this is the GRUB menu, 690 * boot signature and boot signature backup. 691 * str starts with '/'. 692 */ 693 static int 694 is_top_dataset_file(char *str) 695 { 696 char *tptr; 697 698 if ((tptr = grub_strstr(str, "menu.lst")) && 699 (tptr[8] == '\0' || tptr[8] == ' ') && 700 *(tptr-1) == '/') 701 return (1); 702 703 if (grub_strncmp(str, BOOTSIGN_DIR"/", 704 grub_strlen(BOOTSIGN_DIR) + 1) == 0) 705 return (1); 706 707 if (grub_strcmp(str, BOOTSIGN_BACKUP) == 0) 708 return (1); 709 710 return (0); 711 } 712 713 /* 714 * Get the file dnode for a given file name where mdn is the meta dnode 715 * for this ZFS object set. When found, place the file dnode in dn. 716 * The 'path' argument will be mangled. 717 * 718 * Return: 719 * 0 - success 720 * errnum - failure 721 */ 722 static int 723 dnode_get_path(dnode_phys_t *mdn, char *path, dnode_phys_t *dn, 724 char *stack) 725 { 726 uint64_t objnum, version; 727 char *cname, ch; 728 729 if (errnum = dnode_get(mdn, MASTER_NODE_OBJ, DMU_OT_MASTER_NODE, 730 dn, stack)) 731 return (errnum); 732 733 if (errnum = zap_lookup(dn, ZPL_VERSION_STR, &version, stack)) 734 return (errnum); 735 if (version > ZPL_VERSION) 736 return (-1); 737 738 if (errnum = zap_lookup(dn, ZFS_ROOT_OBJ, &objnum, stack)) 739 return (errnum); 740 741 if (errnum = dnode_get(mdn, objnum, DMU_OT_DIRECTORY_CONTENTS, 742 dn, stack)) 743 return (errnum); 744 745 /* skip leading slashes */ 746 while (*path == '/') 747 path++; 748 749 while (*path && !isspace(*path)) { 750 751 /* get the next component name */ 752 cname = path; 753 while (*path && !isspace(*path) && *path != '/') 754 path++; 755 ch = *path; 756 *path = 0; /* ensure null termination */ 757 758 if (errnum = zap_lookup(dn, cname, &objnum, stack)) 759 return (errnum); 760 761 objnum = ZFS_DIRENT_OBJ(objnum); 762 if (errnum = dnode_get(mdn, objnum, 0, dn, stack)) 763 return (errnum); 764 765 *path = ch; 766 while (*path == '/') 767 path++; 768 } 769 770 /* We found the dnode for this file. Verify if it is a plain file. */ 771 VERIFY_DN_TYPE(dn, DMU_OT_PLAIN_FILE_CONTENTS); 772 773 return (0); 774 } 775 776 /* 777 * Get the default 'bootfs' property value from the rootpool. 778 * 779 * Return: 780 * 0 - success 781 * errnum -failure 782 */ 783 static int 784 get_default_bootfsobj(dnode_phys_t *mosmdn, uint64_t *obj, char *stack) 785 { 786 uint64_t objnum = 0; 787 dnode_phys_t *dn = (dnode_phys_t *)stack; 788 stack += DNODE_SIZE; 789 790 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 791 DMU_OT_OBJECT_DIRECTORY, dn, stack)) 792 return (errnum); 793 794 /* 795 * find the object number for 'pool_props', and get the dnode 796 * of the 'pool_props'. 797 */ 798 if (zap_lookup(dn, DMU_POOL_PROPS, &objnum, stack)) 799 return (ERR_FILESYSTEM_NOT_FOUND); 800 801 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_POOL_PROPS, dn, stack)) 802 return (errnum); 803 804 if (zap_lookup(dn, ZPOOL_PROP_BOOTFS, &objnum, stack)) 805 return (ERR_FILESYSTEM_NOT_FOUND); 806 807 if (!objnum) 808 return (ERR_FILESYSTEM_NOT_FOUND); 809 810 *obj = objnum; 811 return (0); 812 } 813 814 /* 815 * Given a MOS metadnode, get the metadnode of a given filesystem name (fsname), 816 * e.g. pool/rootfs, or a given object number (obj), e.g. the object number 817 * of pool/rootfs. 818 * 819 * If no fsname and no obj are given, return the DSL_DIR metadnode. 820 * If fsname is given, return its metadnode and its matching object number. 821 * If only obj is given, return the metadnode for this object number. 822 * 823 * Return: 824 * 0 - success 825 * errnum - failure 826 */ 827 static int 828 get_objset_mdn(dnode_phys_t *mosmdn, char *fsname, uint64_t *obj, 829 dnode_phys_t *mdn, char *stack) 830 { 831 uint64_t objnum, headobj; 832 char *cname, ch; 833 blkptr_t *bp; 834 objset_phys_t *osp; 835 836 if (fsname == NULL && obj) { 837 headobj = *obj; 838 goto skip; 839 } 840 841 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 842 DMU_OT_OBJECT_DIRECTORY, mdn, stack)) 843 return (errnum); 844 845 if (errnum = zap_lookup(mdn, DMU_POOL_ROOT_DATASET, &objnum, 846 stack)) 847 return (errnum); 848 849 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_DSL_DIR, mdn, stack)) 850 return (errnum); 851 852 if (fsname == NULL) { 853 headobj = 854 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 855 goto skip; 856 } 857 858 /* take out the pool name */ 859 while (*fsname && !isspace(*fsname) && *fsname != '/') 860 fsname++; 861 862 while (*fsname && !isspace(*fsname)) { 863 uint64_t childobj; 864 865 while (*fsname == '/') 866 fsname++; 867 868 cname = fsname; 869 while (*fsname && !isspace(*fsname) && *fsname != '/') 870 fsname++; 871 ch = *fsname; 872 *fsname = 0; 873 874 childobj = 875 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_child_dir_zapobj; 876 if (errnum = dnode_get(mosmdn, childobj, 877 DMU_OT_DSL_DIR_CHILD_MAP, mdn, stack)) 878 return (errnum); 879 880 if (zap_lookup(mdn, cname, &objnum, stack)) 881 return (ERR_FILESYSTEM_NOT_FOUND); 882 883 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_DSL_DIR, 884 mdn, stack)) 885 return (errnum); 886 887 *fsname = ch; 888 } 889 headobj = ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 890 if (obj) 891 *obj = headobj; 892 893 skip: 894 if (errnum = dnode_get(mosmdn, headobj, DMU_OT_DSL_DATASET, mdn, stack)) 895 return (errnum); 896 897 /* TODO: Add snapshot support here - for fsname=snapshot-name */ 898 899 bp = &((dsl_dataset_phys_t *)DN_BONUS(mdn))->ds_bp; 900 osp = (objset_phys_t *)stack; 901 stack += sizeof (objset_phys_t); 902 if (errnum = zio_read(bp, osp, stack)) 903 return (errnum); 904 905 grub_memmove((char *)mdn, (char *)&osp->os_meta_dnode, DNODE_SIZE); 906 907 return (0); 908 } 909 910 /* 911 * For a given XDR packed nvlist, verify the first 4 bytes and move on. 912 * 913 * An XDR packed nvlist is encoded as (comments from nvs_xdr_create) : 914 * 915 * encoding method/host endian (4 bytes) 916 * nvl_version (4 bytes) 917 * nvl_nvflag (4 bytes) 918 * encoded nvpairs: 919 * encoded size of the nvpair (4 bytes) 920 * decoded size of the nvpair (4 bytes) 921 * name string size (4 bytes) 922 * name string data (sizeof(NV_ALIGN4(string)) 923 * data type (4 bytes) 924 * # of elements in the nvpair (4 bytes) 925 * data 926 * 2 zero's for the last nvpair 927 * (end of the entire list) (8 bytes) 928 * 929 * Return: 930 * 0 - success 931 * 1 - failure 932 */ 933 static int 934 nvlist_unpack(char *nvlist, char **out) 935 { 936 /* Verify if the 1st and 2nd byte in the nvlist are valid. */ 937 if (nvlist[0] != NV_ENCODE_XDR || nvlist[1] != HOST_ENDIAN) 938 return (1); 939 940 nvlist += 4; 941 *out = nvlist; 942 return (0); 943 } 944 945 static char * 946 nvlist_array(char *nvlist, int index) 947 { 948 int i, encode_size; 949 950 for (i = 0; i < index; i++) { 951 /* skip the header, nvl_version, and nvl_nvflag */ 952 nvlist = nvlist + 4 * 2; 953 954 while (encode_size = BSWAP_32(*(uint32_t *)nvlist)) 955 nvlist += encode_size; /* goto the next nvpair */ 956 957 nvlist = nvlist + 4 * 2; /* skip the ending 2 zeros - 8 bytes */ 958 } 959 960 return (nvlist); 961 } 962 963 static int 964 nvlist_lookup_value(char *nvlist, char *name, void *val, int valtype, 965 int *nelmp) 966 { 967 int name_len, type, slen, encode_size; 968 char *nvpair, *nvp_name, *strval = val; 969 uint64_t *intval = val; 970 971 /* skip the header, nvl_version, and nvl_nvflag */ 972 nvlist = nvlist + 4 * 2; 973 974 /* 975 * Loop thru the nvpair list 976 * The XDR representation of an integer is in big-endian byte order. 977 */ 978 while (encode_size = BSWAP_32(*(uint32_t *)nvlist)) { 979 980 nvpair = nvlist + 4 * 2; /* skip the encode/decode size */ 981 982 name_len = BSWAP_32(*(uint32_t *)nvpair); 983 nvpair += 4; 984 985 nvp_name = nvpair; 986 nvpair = nvpair + ((name_len + 3) & ~3); /* align */ 987 988 type = BSWAP_32(*(uint32_t *)nvpair); 989 nvpair += 4; 990 991 if ((grub_strncmp(nvp_name, name, name_len) == 0) && 992 type == valtype) { 993 int nelm; 994 995 if ((nelm = BSWAP_32(*(uint32_t *)nvpair)) < 1) 996 return (1); 997 nvpair += 4; 998 999 switch (valtype) { 1000 case DATA_TYPE_STRING: 1001 slen = BSWAP_32(*(uint32_t *)nvpair); 1002 nvpair += 4; 1003 grub_memmove(strval, nvpair, slen); 1004 strval[slen] = '\0'; 1005 return (0); 1006 1007 case DATA_TYPE_UINT64: 1008 *intval = BSWAP_64(*(uint64_t *)nvpair); 1009 return (0); 1010 1011 case DATA_TYPE_NVLIST: 1012 *(void **)val = (void *)nvpair; 1013 return (0); 1014 1015 case DATA_TYPE_NVLIST_ARRAY: 1016 *(void **)val = (void *)nvpair; 1017 if (nelmp) 1018 *nelmp = nelm; 1019 return (0); 1020 } 1021 } 1022 1023 nvlist += encode_size; /* goto the next nvpair */ 1024 } 1025 1026 return (1); 1027 } 1028 1029 /* 1030 * Check if this vdev is online and is in a good state. 1031 */ 1032 static int 1033 vdev_validate(char *nv) 1034 { 1035 uint64_t ival; 1036 1037 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_OFFLINE, &ival, 1038 DATA_TYPE_UINT64, NULL) == 0 || 1039 nvlist_lookup_value(nv, ZPOOL_CONFIG_FAULTED, &ival, 1040 DATA_TYPE_UINT64, NULL) == 0 || 1041 nvlist_lookup_value(nv, ZPOOL_CONFIG_REMOVED, &ival, 1042 DATA_TYPE_UINT64, NULL) == 0) 1043 return (ERR_DEV_VALUES); 1044 1045 return (0); 1046 } 1047 1048 /* 1049 * Get a list of valid vdev pathname from the boot device. 1050 * The caller should already allocate MAXNAMELEN memory for bootpath. 1051 */ 1052 int 1053 vdev_get_bootpath(char *nv, uint64_t inguid, char *devid, char *bootpath) 1054 { 1055 char type[16]; 1056 1057 bootpath[0] = '\0'; 1058 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_TYPE, &type, DATA_TYPE_STRING, 1059 NULL)) 1060 return (ERR_FSYS_CORRUPT); 1061 1062 if (strcmp(type, VDEV_TYPE_DISK) == 0) { 1063 if (vdev_validate(nv) != 0 || 1064 (nvlist_lookup_value(nv, ZPOOL_CONFIG_PHYS_PATH, 1065 bootpath, DATA_TYPE_STRING, NULL) != 0) || 1066 (nvlist_lookup_value(nv, ZPOOL_CONFIG_DEVID, 1067 devid, DATA_TYPE_STRING, NULL) != 0)) 1068 return (ERR_NO_BOOTPATH); 1069 1070 } else if (strcmp(type, VDEV_TYPE_MIRROR) == 0) { 1071 int nelm, i; 1072 char *child; 1073 1074 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_CHILDREN, &child, 1075 DATA_TYPE_NVLIST_ARRAY, &nelm)) 1076 return (ERR_FSYS_CORRUPT); 1077 1078 for (i = 0; i < nelm; i++) { 1079 char tmp_path[MAXNAMELEN]; 1080 char tmp_devid[MAXNAMELEN]; 1081 char *child_i; 1082 uint64_t guid; 1083 1084 child_i = nvlist_array(child, i); 1085 if (vdev_validate(child_i) != 0) 1086 continue; 1087 1088 if (nvlist_lookup_value(child_i, ZPOOL_CONFIG_PHYS_PATH, 1089 tmp_path, DATA_TYPE_STRING, NULL) != 0) 1090 return (ERR_NO_BOOTPATH); 1091 1092 if ((strlen(bootpath) + strlen(tmp_path)) > MAXNAMELEN) 1093 return (ERR_WONT_FIT); 1094 1095 if (nvlist_lookup_value(child_i, ZPOOL_CONFIG_GUID, 1096 &guid, DATA_TYPE_UINT64, NULL) != 0) 1097 return (ERR_NO_BOOTPATH); 1098 if (nvlist_lookup_value(child_i, ZPOOL_CONFIG_DEVID, 1099 tmp_devid, DATA_TYPE_STRING, NULL) != 0) 1100 return (ERR_NO_BOOTPATH); 1101 if (guid == inguid) { 1102 sprintf(devid, "%s", tmp_devid); 1103 sprintf(bootpath, "%s", tmp_path); 1104 break; 1105 } 1106 } 1107 } 1108 1109 return (strlen(bootpath) > 0 ? 0 : ERR_NO_BOOTPATH); 1110 } 1111 1112 /* 1113 * Check the disk label information and retrieve needed vdev name-value pairs. 1114 * 1115 * Return: 1116 * 0 - success 1117 * ERR_* - failure 1118 */ 1119 int 1120 check_pool_label(int label, char *stack, char *outdevid, char *outpath) 1121 { 1122 vdev_phys_t *vdev; 1123 uint64_t sector, pool_state, txg = 0; 1124 char *nvlist, *nv; 1125 uint64_t diskguid; 1126 1127 sector = (label * sizeof (vdev_label_t) + VDEV_SKIP_SIZE + 1128 VDEV_BOOT_HEADER_SIZE) >> SPA_MINBLOCKSHIFT; 1129 1130 /* Read in the vdev name-value pair list (112K). */ 1131 if (devread(sector, 0, VDEV_PHYS_SIZE, stack) == 0) 1132 return (ERR_READ); 1133 1134 vdev = (vdev_phys_t *)stack; 1135 stack += sizeof (vdev_phys_t); 1136 1137 if (nvlist_unpack(vdev->vp_nvlist, &nvlist)) 1138 return (ERR_FSYS_CORRUPT); 1139 1140 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_STATE, &pool_state, 1141 DATA_TYPE_UINT64, NULL)) 1142 return (ERR_FSYS_CORRUPT); 1143 1144 if (pool_state == POOL_STATE_DESTROYED) 1145 return (ERR_FILESYSTEM_NOT_FOUND); 1146 1147 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_NAME, 1148 current_rootpool, DATA_TYPE_STRING, NULL)) 1149 return (ERR_FSYS_CORRUPT); 1150 1151 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_TXG, &txg, 1152 DATA_TYPE_UINT64, NULL)) 1153 return (ERR_FSYS_CORRUPT); 1154 1155 /* not an active device */ 1156 if (txg == 0) 1157 return (ERR_NO_BOOTPATH); 1158 1159 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_VDEV_TREE, &nv, 1160 DATA_TYPE_NVLIST, NULL)) 1161 return (ERR_FSYS_CORRUPT); 1162 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_GUID, &diskguid, 1163 DATA_TYPE_UINT64, NULL)) 1164 return (ERR_FSYS_CORRUPT); 1165 if (vdev_get_bootpath(nv, diskguid, outdevid, outpath)) 1166 return (ERR_NO_BOOTPATH); 1167 return (0); 1168 } 1169 1170 /* 1171 * zfs_mount() locates a valid uberblock of the root pool and read in its MOS 1172 * to the memory address MOS. 1173 * 1174 * Return: 1175 * 1 - success 1176 * 0 - failure 1177 */ 1178 int 1179 zfs_mount(void) 1180 { 1181 char *stack; 1182 int label = 0; 1183 uberblock_phys_t *ub_array, *ubbest = NULL; 1184 vdev_boot_header_t *bh; 1185 objset_phys_t *osp; 1186 char tmp_bootpath[MAXNAMELEN]; 1187 char tmp_devid[MAXNAMELEN]; 1188 1189 /* if it's our first time here, zero the best uberblock out */ 1190 if (best_drive == 0 && best_part == 0 && find_best_root) 1191 grub_memset(¤t_uberblock, 0, sizeof (uberblock_t)); 1192 1193 stackbase = ZFS_SCRATCH; 1194 stack = stackbase; 1195 ub_array = (uberblock_phys_t *)stack; 1196 stack += VDEV_UBERBLOCK_RING; 1197 1198 bh = (vdev_boot_header_t *)stack; 1199 stack += VDEV_BOOT_HEADER_SIZE; 1200 1201 osp = (objset_phys_t *)stack; 1202 stack += sizeof (objset_phys_t); 1203 1204 /* XXX add back labels support? */ 1205 for (label = 0; ubbest == NULL && label < (VDEV_LABELS/2); label++) { 1206 uint64_t sector = (label * sizeof (vdev_label_t) + 1207 VDEV_SKIP_SIZE) >> SPA_MINBLOCKSHIFT; 1208 if (devread(sector, 0, VDEV_BOOT_HEADER_SIZE, 1209 (char *)bh) == 0) 1210 continue; 1211 if ((bh->vb_magic != VDEV_BOOT_MAGIC) || 1212 (bh->vb_version != VDEV_BOOT_VERSION)) { 1213 continue; 1214 } 1215 sector += (VDEV_BOOT_HEADER_SIZE + 1216 VDEV_PHYS_SIZE) >> SPA_MINBLOCKSHIFT; 1217 1218 /* Read in the uberblock ring (128K). */ 1219 if (devread(sector, 0, VDEV_UBERBLOCK_RING, 1220 (char *)ub_array) == 0) 1221 continue; 1222 1223 if ((ubbest = find_bestub(ub_array, label)) != NULL && 1224 zio_read(&ubbest->ubp_uberblock.ub_rootbp, osp, stack) 1225 == 0) { 1226 1227 VERIFY_OS_TYPE(osp, DMU_OST_META); 1228 1229 if (check_pool_label(label, stack, tmp_devid, 1230 tmp_bootpath)) 1231 return (0); 1232 1233 if (find_best_root && 1234 vdev_uberblock_compare(&ubbest->ubp_uberblock, 1235 &(current_uberblock)) <= 0) 1236 continue; 1237 /* Got the MOS. Save it at the memory addr MOS. */ 1238 grub_memmove(MOS, &osp->os_meta_dnode, DNODE_SIZE); 1239 grub_memmove(¤t_uberblock, 1240 &ubbest->ubp_uberblock, 1241 sizeof (uberblock_t)); 1242 grub_memmove(current_bootpath, tmp_bootpath, 1243 MAXNAMELEN); 1244 grub_memmove(current_devid, tmp_devid, 1245 grub_strlen(tmp_devid)); 1246 is_zfs_mount = 1; 1247 return (1); 1248 } 1249 } 1250 1251 return (0); 1252 } 1253 1254 /* 1255 * zfs_open() locates a file in the rootpool by following the 1256 * MOS and places the dnode of the file in the memory address DNODE. 1257 * 1258 * Return: 1259 * 1 - success 1260 * 0 - failure 1261 */ 1262 int 1263 zfs_open(char *filename) 1264 { 1265 char *stack; 1266 dnode_phys_t *mdn; 1267 1268 file_buf = NULL; 1269 stackbase = ZFS_SCRATCH; 1270 stack = stackbase; 1271 1272 mdn = (dnode_phys_t *)stack; 1273 stack += sizeof (dnode_phys_t); 1274 1275 dnode_mdn = NULL; 1276 dnode_buf = (dnode_phys_t *)stack; 1277 stack += 1<<DNODE_BLOCK_SHIFT; 1278 1279 /* 1280 * menu.lst is placed at the root pool filesystem level, 1281 * do not goto 'current_bootfs'. 1282 */ 1283 if (is_top_dataset_file(filename)) { 1284 if (errnum = get_objset_mdn(MOS, NULL, NULL, mdn, stack)) 1285 return (0); 1286 1287 current_bootfs_obj = 0; 1288 } else { 1289 if (current_bootfs[0] == '\0') { 1290 /* Get the default root filesystem object number */ 1291 if (errnum = get_default_bootfsobj(MOS, 1292 ¤t_bootfs_obj, stack)) 1293 return (0); 1294 1295 if (errnum = get_objset_mdn(MOS, NULL, 1296 ¤t_bootfs_obj, mdn, stack)) 1297 return (0); 1298 } else { 1299 if (errnum = get_objset_mdn(MOS, current_bootfs, 1300 ¤t_bootfs_obj, mdn, stack)) { 1301 grub_memset(current_bootfs, 0, MAXNAMELEN); 1302 return (0); 1303 } 1304 } 1305 } 1306 1307 if (dnode_get_path(mdn, filename, DNODE, stack)) { 1308 errnum = ERR_FILE_NOT_FOUND; 1309 return (0); 1310 } 1311 1312 /* get the file size and set the file position to 0 */ 1313 filemax = ((znode_phys_t *)DN_BONUS(DNODE))->zp_size; 1314 filepos = 0; 1315 1316 dnode_buf = NULL; 1317 return (1); 1318 } 1319 1320 /* 1321 * zfs_read reads in the data blocks pointed by the DNODE. 1322 * 1323 * Return: 1324 * len - the length successfully read in to the buffer 1325 * 0 - failure 1326 */ 1327 int 1328 zfs_read(char *buf, int len) 1329 { 1330 char *stack; 1331 char *tmpbuf; 1332 int blksz, length, movesize; 1333 1334 if (file_buf == NULL) { 1335 file_buf = stackbase; 1336 stackbase += SPA_MAXBLOCKSIZE; 1337 file_start = file_end = 0; 1338 } 1339 stack = stackbase; 1340 1341 /* 1342 * If offset is in memory, move it into the buffer provided and return. 1343 */ 1344 if (filepos >= file_start && filepos+len <= file_end) { 1345 grub_memmove(buf, file_buf + filepos - file_start, len); 1346 filepos += len; 1347 return (len); 1348 } 1349 1350 blksz = DNODE->dn_datablkszsec << SPA_MINBLOCKSHIFT; 1351 1352 /* 1353 * Entire Dnode is too big to fit into the space available. We 1354 * will need to read it in chunks. This could be optimized to 1355 * read in as large a chunk as there is space available, but for 1356 * now, this only reads in one data block at a time. 1357 */ 1358 length = len; 1359 while (length) { 1360 /* 1361 * Find requested blkid and the offset within that block. 1362 */ 1363 uint64_t blkid = filepos / blksz; 1364 1365 if (errnum = dmu_read(DNODE, blkid, file_buf, stack)) 1366 return (0); 1367 1368 file_start = blkid * blksz; 1369 file_end = file_start + blksz; 1370 1371 movesize = MIN(length, file_end - filepos); 1372 1373 grub_memmove(buf, file_buf + filepos - file_start, 1374 movesize); 1375 buf += movesize; 1376 length -= movesize; 1377 filepos += movesize; 1378 } 1379 1380 return (len); 1381 } 1382 1383 /* 1384 * No-Op 1385 */ 1386 int 1387 zfs_embed(int *start_sector, int needed_sectors) 1388 { 1389 return (1); 1390 } 1391 1392 #endif /* FSYS_ZFS */ 1393