1 /* $NetBSD: chfs_scan.c,v 1.10 2021/07/16 21:18:41 andvar Exp $ */ 2 3 /*- 4 * Copyright (c) 2010 Department of Software Engineering, 5 * University of Szeged, Hungary 6 * Copyright (c) 2010 David Tengeri <dtengeri (at) inf.u-szeged.hu> 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by the Department of Software Engineering, University of Szeged, Hungary 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "chfs.h" 35 36 /* 37 * chfs_scan_make_vnode_cache - makes a new vnode cache during scan 38 * This function returns a vnode cache belonging to @vno. 39 */ 40 struct chfs_vnode_cache * 41 chfs_scan_make_vnode_cache(struct chfs_mount *chmp, ino_t vno) 42 { 43 struct chfs_vnode_cache *vc; 44 45 KASSERT(mutex_owned(&chmp->chm_lock_vnocache)); 46 47 /* vnode cache already exists */ 48 vc = chfs_vnode_cache_get(chmp, vno); 49 if (vc) { 50 return vc; 51 } 52 53 /* update max vnode number if needed */ 54 if (vno > chmp->chm_max_vno) { 55 chmp->chm_max_vno = vno; 56 } 57 58 /* create new vnode cache */ 59 vc = chfs_vnode_cache_alloc(vno); 60 61 chfs_vnode_cache_add(chmp, vc); 62 63 if (vno == CHFS_ROOTINO) { 64 vc->nlink = 2; 65 vc->pvno = CHFS_ROOTINO; 66 vc->state = VNO_STATE_CHECKEDABSENT; 67 } 68 69 return vc; 70 } 71 72 /* 73 * chfs_scan_check_node_hdr - checks node magic and crc 74 * Returns 0 if everything is OK, error code otherwise. 75 */ 76 int 77 chfs_scan_check_node_hdr(struct chfs_flash_node_hdr *nhdr) 78 { 79 uint16_t magic; 80 uint32_t crc, hdr_crc; 81 82 magic = le16toh(nhdr->magic); 83 84 if (magic != CHFS_FS_MAGIC_BITMASK) { 85 dbg("bad magic\n"); 86 return CHFS_NODE_BADMAGIC; 87 } 88 89 hdr_crc = le32toh(nhdr->hdr_crc); 90 crc = crc32(0, (uint8_t *)nhdr, CHFS_NODE_HDR_SIZE - 4); 91 92 if (crc != hdr_crc) { 93 dbg("bad crc\n"); 94 return CHFS_NODE_BADCRC; 95 } 96 97 return CHFS_NODE_OK; 98 } 99 100 /* chfs_scan_check_vnode - check vnode crc and add it to vnode cache */ 101 int 102 chfs_scan_check_vnode(struct chfs_mount *chmp, 103 struct chfs_eraseblock *cheb, void *buf, off_t ofs) 104 { 105 KASSERT(mutex_owned(&chmp->chm_lock_mountfields)); 106 struct chfs_vnode_cache *vc; 107 struct chfs_flash_vnode *vnode = buf; 108 struct chfs_node_ref *nref; 109 int err; 110 uint32_t crc; 111 ino_t vno; 112 113 crc = crc32(0, (uint8_t *)vnode, 114 sizeof(struct chfs_flash_vnode) - 4); 115 116 /* check node crc */ 117 if (crc != le32toh(vnode->node_crc)) { 118 err = chfs_update_eb_dirty(chmp, 119 cheb, le32toh(vnode->length)); 120 if (err) { 121 return err; 122 } 123 124 return CHFS_NODE_BADCRC; 125 } 126 127 vno = le64toh(vnode->vno); 128 129 /* find the corresponding vnode cache */ 130 mutex_enter(&chmp->chm_lock_vnocache); 131 vc = chfs_vnode_cache_get(chmp, vno); 132 if (!vc) { 133 vc = chfs_scan_make_vnode_cache(chmp, vno); 134 if (!vc) { 135 mutex_exit(&chmp->chm_lock_vnocache); 136 return ENOMEM; 137 } 138 } 139 140 nref = chfs_alloc_node_ref(cheb); 141 142 nref->nref_offset = ofs; 143 144 KASSERT(nref->nref_lnr == cheb->lnr); 145 146 /* check version of vnode */ 147 if ((struct chfs_vnode_cache *)vc->v != vc) { 148 if (le64toh(vnode->version) > *vc->vno_version) { 149 *vc->vno_version = le64toh(vnode->version); 150 chfs_add_vnode_ref_to_vc(chmp, vc, nref); 151 } else { 152 err = chfs_update_eb_dirty(chmp, cheb, 153 sizeof(struct chfs_flash_vnode)); 154 mutex_exit(&chmp->chm_lock_vnocache); 155 return CHFS_NODE_OK; 156 } 157 } else { 158 vc->vno_version = kmem_alloc(sizeof(uint64_t), KM_SLEEP); 159 *vc->vno_version = le64toh(vnode->version); 160 chfs_add_vnode_ref_to_vc(chmp, vc, nref); 161 } 162 mutex_exit(&chmp->chm_lock_vnocache); 163 164 /* update sizes */ 165 mutex_enter(&chmp->chm_lock_sizes); 166 chfs_change_size_free(chmp, cheb, -le32toh(vnode->length)); 167 chfs_change_size_used(chmp, cheb, le32toh(vnode->length)); 168 mutex_exit(&chmp->chm_lock_sizes); 169 170 KASSERT(cheb->used_size <= chmp->chm_ebh->eb_size); 171 172 KASSERT(cheb->used_size + cheb->free_size + cheb->dirty_size + cheb->unchecked_size + cheb->wasted_size == chmp->chm_ebh->eb_size); 173 174 return CHFS_NODE_OK; 175 } 176 177 /* chfs_scan_mark_dirent_obsolete - marks a directory entry "obsolete" */ 178 int 179 chfs_scan_mark_dirent_obsolete(struct chfs_mount *chmp, 180 struct chfs_vnode_cache *vc, struct chfs_dirent *fd) 181 { 182 struct chfs_eraseblock *cheb __diagused; 183 struct chfs_node_ref *prev, *nref; 184 185 nref = fd->nref; 186 cheb = &chmp->chm_blocks[fd->nref->nref_lnr]; 187 188 /* remove dirent's node ref from vnode cache */ 189 prev = vc->dirents; 190 if (prev && prev == nref) { 191 vc->dirents = prev->nref_next; 192 } else if (prev && prev != (void *)vc) { 193 while (prev->nref_next && prev->nref_next != (void *)vc) { 194 if (prev->nref_next == nref) { 195 prev->nref_next = nref->nref_next; 196 break; 197 } 198 prev = prev->nref_next; 199 } 200 } 201 202 KASSERT(cheb->used_size + cheb->free_size + cheb->dirty_size + 203 cheb->unchecked_size + cheb->wasted_size == chmp->chm_ebh->eb_size); 204 205 return 0; 206 } 207 208 /* chfs_add_fd_to_list - adds a directory entry to its parent's vnode cache */ 209 void 210 chfs_add_fd_to_list(struct chfs_mount *chmp, 211 struct chfs_dirent *new, struct chfs_vnode_cache *pvc) 212 { 213 KASSERT(mutex_owned(&chmp->chm_lock_mountfields)); 214 int size; 215 struct chfs_eraseblock *cheb, *oldcheb; 216 struct chfs_dirent *fd, *tmpfd; 217 218 dbg("adding fd to list: %s\n", new->name); 219 220 /* update highest version if needed */ 221 if ((new->version > pvc->highest_version)) 222 pvc->highest_version = new->version; 223 224 size = CHFS_PAD(sizeof(struct chfs_flash_dirent_node) + 225 new->nsize); 226 cheb = &chmp->chm_blocks[new->nref->nref_lnr]; 227 228 mutex_enter(&chmp->chm_lock_sizes); 229 TAILQ_FOREACH_SAFE(fd, &pvc->scan_dirents, fds, tmpfd) { 230 if (fd->nhash > new->nhash) { 231 /* insert new before fd */ 232 TAILQ_INSERT_BEFORE(fd, new, fds); 233 goto out; 234 } else if (fd->nhash == new->nhash && 235 !strcmp(fd->name, new->name)) { 236 if (new->version > fd->version) { 237 /* replace fd with new */ 238 TAILQ_INSERT_BEFORE(fd, new, fds); 239 chfs_change_size_free(chmp, cheb, -size); 240 chfs_change_size_used(chmp, cheb, size); 241 242 TAILQ_REMOVE(&pvc->scan_dirents, fd, fds); 243 if (fd->nref) { 244 size = CHFS_PAD(sizeof(struct chfs_flash_dirent_node) + fd->nsize); 245 chfs_scan_mark_dirent_obsolete(chmp, pvc, fd); 246 oldcheb = &chmp->chm_blocks[fd->nref->nref_lnr]; 247 chfs_change_size_used(chmp, oldcheb, -size); 248 chfs_change_size_dirty(chmp, oldcheb, size); 249 } 250 chfs_free_dirent(fd); 251 } else { 252 /* new dirent is older */ 253 chfs_scan_mark_dirent_obsolete(chmp, pvc, new); 254 chfs_change_size_free(chmp, cheb, -size); 255 chfs_change_size_dirty(chmp, cheb, size); 256 chfs_free_dirent(new); 257 } 258 mutex_exit(&chmp->chm_lock_sizes); 259 return; 260 } 261 } 262 /* if we couldnt fit it elsewhere, lets add to the end */ 263 TAILQ_INSERT_TAIL(&pvc->scan_dirents, new, fds); 264 265 out: 266 /* update sizes */ 267 chfs_change_size_free(chmp, cheb, -size); 268 chfs_change_size_used(chmp, cheb, size); 269 mutex_exit(&chmp->chm_lock_sizes); 270 271 KASSERT(cheb->used_size <= chmp->chm_ebh->eb_size); 272 273 KASSERT(cheb->used_size + cheb->free_size + cheb->dirty_size + cheb->unchecked_size + cheb->wasted_size == chmp->chm_ebh->eb_size); 274 } 275 276 /* chfs_scan_check_dirent_node - check vnode crc and add to vnode cache */ 277 int 278 chfs_scan_check_dirent_node(struct chfs_mount *chmp, 279 struct chfs_eraseblock *cheb, void *buf, off_t ofs) 280 { 281 int err, namelen; 282 uint32_t crc; 283 struct chfs_dirent *fd; 284 struct chfs_vnode_cache *parentvc; 285 struct chfs_flash_dirent_node *dirent = buf; 286 287 /* check crc */ 288 crc = crc32(0, (uint8_t *)dirent, sizeof(*dirent) - 4); 289 if (crc != le32toh(dirent->node_crc)) { 290 err = chfs_update_eb_dirty(chmp, cheb, le32toh(dirent->length)); 291 if (err) 292 return err; 293 return CHFS_NODE_BADCRC; 294 } 295 296 /* allocate space for name */ 297 namelen = dirent->nsize; 298 299 fd = chfs_alloc_dirent(namelen + 1); 300 if (!fd) 301 return ENOMEM; 302 303 /* allocate an nref */ 304 fd->nref = chfs_alloc_node_ref(cheb); 305 if (!fd->nref) 306 return ENOMEM; 307 308 KASSERT(fd->nref->nref_lnr == cheb->lnr); 309 310 memcpy(&fd->name, dirent->name, namelen); 311 fd->nsize = namelen; 312 fd->name[namelen] = 0; 313 crc = crc32(0, fd->name, dirent->nsize); 314 if (crc != le32toh(dirent->name_crc)) { 315 chfs_err("Directory entry's name has bad crc: read: 0x%x, " 316 "calculated: 0x%x\n", le32toh(dirent->name_crc), crc); 317 chfs_free_dirent(fd); 318 err = chfs_update_eb_dirty(chmp, cheb, le32toh(dirent->length)); 319 if (err) 320 return err; 321 return CHFS_NODE_BADNAMECRC; 322 } 323 324 /* check vnode_cache of parent node */ 325 mutex_enter(&chmp->chm_lock_vnocache); 326 parentvc = chfs_scan_make_vnode_cache(chmp, le64toh(dirent->pvno)); 327 if (!parentvc) { 328 chfs_free_dirent(fd); 329 mutex_exit(&chmp->chm_lock_vnocache); 330 return ENOMEM; 331 } 332 333 fd->nref->nref_offset = ofs; 334 335 dbg("add dirent to #%llu\n", (unsigned long long)parentvc->vno); 336 chfs_add_node_to_list(chmp, parentvc, fd->nref, &parentvc->dirents); 337 mutex_exit(&chmp->chm_lock_vnocache); 338 339 fd->vno = le64toh(dirent->vno); 340 fd->version = le64toh(dirent->version); 341 fd->nhash = hash32_buf(fd->name, namelen, HASH32_BUF_INIT); 342 fd->type = dirent->dtype; 343 344 chfs_add_fd_to_list(chmp, fd, parentvc); 345 346 return CHFS_NODE_OK; 347 } 348 349 /* chfs_scan_check_data_node - check vnode crc and add to vnode cache */ 350 int 351 chfs_scan_check_data_node(struct chfs_mount *chmp, 352 struct chfs_eraseblock *cheb, void *buf, off_t ofs) 353 { 354 KASSERT(mutex_owned(&chmp->chm_lock_mountfields)); 355 int err; 356 uint32_t crc, vno; 357 struct chfs_node_ref *nref; 358 struct chfs_vnode_cache *vc; 359 struct chfs_flash_data_node *dnode = buf; 360 361 /* check crc */ 362 crc = crc32(0, (uint8_t *)dnode, sizeof(struct chfs_flash_data_node) - 4); 363 if (crc != le32toh(dnode->node_crc)) { 364 err = chfs_update_eb_dirty(chmp, cheb, le32toh(dnode->length)); 365 if (err) 366 return err; 367 return CHFS_NODE_BADCRC; 368 } 369 /* 370 * Don't check data nodes crc and version here, it will be done in 371 * the background GC thread. 372 */ 373 nref = chfs_alloc_node_ref(cheb); 374 if (!nref) 375 return ENOMEM; 376 377 nref->nref_offset = CHFS_GET_OFS(ofs) | CHFS_UNCHECKED_NODE_MASK; 378 379 KASSERT(nref->nref_lnr == cheb->lnr); 380 381 vno = le64toh(dnode->vno); 382 mutex_enter(&chmp->chm_lock_vnocache); 383 vc = chfs_vnode_cache_get(chmp, vno); 384 if (!vc) { 385 vc = chfs_scan_make_vnode_cache(chmp, vno); 386 if (!vc) { 387 mutex_exit(&chmp->chm_lock_vnocache); 388 return ENOMEM; 389 } 390 } 391 chfs_add_node_to_list(chmp, vc, nref, &vc->dnode); 392 mutex_exit(&chmp->chm_lock_vnocache); 393 394 dbg("chmpfree: %u, chebfree: %u, dnode: %u\n", chmp->chm_free_size, cheb->free_size, dnode->length); 395 396 /* update sizes */ 397 mutex_enter(&chmp->chm_lock_sizes); 398 chfs_change_size_free(chmp, cheb, -dnode->length); 399 chfs_change_size_unchecked(chmp, cheb, dnode->length); 400 mutex_exit(&chmp->chm_lock_sizes); 401 return CHFS_NODE_OK; 402 } 403 404 /* chfs_scan_classify_cheb - determine eraseblock's state */ 405 int 406 chfs_scan_classify_cheb(struct chfs_mount *chmp, 407 struct chfs_eraseblock *cheb) 408 { 409 if (cheb->free_size == chmp->chm_ebh->eb_size) 410 return CHFS_BLK_STATE_FREE; 411 else if (cheb->dirty_size < MAX_DIRTY_TO_CLEAN) 412 return CHFS_BLK_STATE_CLEAN; 413 else if (cheb->used_size || cheb->unchecked_size) 414 return CHFS_BLK_STATE_PARTDIRTY; 415 else 416 return CHFS_BLK_STATE_ALLDIRTY; 417 } 418 419 420 /* 421 * chfs_scan_eraseblock - scans an eraseblock and looking for nodes 422 * 423 * This function scans a whole eraseblock, checks the nodes on it and add them 424 * to the vnode cache. 425 * Returns eraseblock state on success, error code if fails. 426 */ 427 int 428 chfs_scan_eraseblock(struct chfs_mount *chmp, 429 struct chfs_eraseblock *cheb) 430 { 431 int err; 432 size_t len, retlen; 433 off_t ofs = 0; 434 int lnr = cheb->lnr; 435 u_char *buf; 436 struct chfs_flash_node_hdr *nhdr; 437 int read_free = 0; 438 struct chfs_node_ref *nref; 439 440 dbg("scanning eraseblock content: %d free_size: %d\n", cheb->lnr, cheb->free_size); 441 dbg("scanned physical block: %d\n", chmp->chm_ebh->lmap[lnr]); 442 buf = kmem_alloc(CHFS_MAX_NODE_SIZE, KM_SLEEP); 443 444 while((ofs + CHFS_NODE_HDR_SIZE) < chmp->chm_ebh->eb_size) { 445 memset(buf, 0 , CHFS_MAX_NODE_SIZE); 446 err = chfs_read_leb(chmp, 447 lnr, buf, ofs, CHFS_NODE_HDR_SIZE, &retlen); 448 if (err) 449 goto err_return; 450 451 if (retlen != CHFS_NODE_HDR_SIZE) { 452 chfs_err("Error reading node header: " 453 "read: %zu instead of: %zu\n", 454 CHFS_NODE_HDR_SIZE, retlen); 455 err = EIO; 456 goto err_return; 457 } 458 459 /* first we check if the buffer we read is full with 0xff, if yes maybe 460 * the blocks remaining area is free. We increase read_free and if it 461 * reaches MAX_READ_FREE we stop reading the block */ 462 if (check_pattern(buf, 0xff, 0, CHFS_NODE_HDR_SIZE)) { 463 read_free += CHFS_NODE_HDR_SIZE; 464 if (read_free >= MAX_READ_FREE(chmp)) { 465 dbg("rest of the block is free. Size: %d\n", cheb->free_size); 466 kmem_free(buf, CHFS_MAX_NODE_SIZE); 467 return chfs_scan_classify_cheb(chmp, cheb); 468 } 469 ofs += CHFS_NODE_HDR_SIZE; 470 continue; 471 } else { 472 chfs_update_eb_dirty(chmp, cheb, read_free); 473 read_free = 0; 474 } 475 476 nhdr = (struct chfs_flash_node_hdr *)buf; 477 478 err = chfs_scan_check_node_hdr(nhdr); 479 if (err) { 480 dbg("node hdr error\n"); 481 err = chfs_update_eb_dirty(chmp, cheb, 4); 482 if (err) 483 goto err_return; 484 485 ofs += 4; 486 continue; 487 } 488 ofs += CHFS_NODE_HDR_SIZE; 489 if (ofs > chmp->chm_ebh->eb_size) { 490 chfs_err("Second part of node is on the next eraseblock.\n"); 491 err = EIO; 492 goto err_return; 493 } 494 switch (le16toh(nhdr->type)) { 495 case CHFS_NODETYPE_VNODE: 496 /* vnode information */ 497 /* read up the node */ 498 len = le32toh(nhdr->length) - CHFS_NODE_HDR_SIZE; 499 err = chfs_read_leb(chmp, 500 lnr, buf + CHFS_NODE_HDR_SIZE, 501 ofs, len, &retlen); 502 if (err) 503 goto err_return; 504 505 if (retlen != len) { 506 chfs_err("Error reading vnode: read: %zu instead of: %zu\n", 507 len, retlen); 508 err = EIO; 509 goto err_return; 510 } 511 KASSERT(lnr == cheb->lnr); 512 err = chfs_scan_check_vnode(chmp, 513 cheb, buf, ofs - CHFS_NODE_HDR_SIZE); 514 if (err) 515 goto err_return; 516 517 break; 518 case CHFS_NODETYPE_DIRENT: 519 /* directory entry */ 520 /* read up the node */ 521 len = le32toh(nhdr->length) - CHFS_NODE_HDR_SIZE; 522 523 err = chfs_read_leb(chmp, 524 lnr, buf + CHFS_NODE_HDR_SIZE, 525 ofs, len, &retlen); 526 if (err) 527 goto err_return; 528 529 if (retlen != len) { 530 chfs_err("Error reading dirent node: read: %zu " 531 "instead of: %zu\n", len, retlen); 532 err = EIO; 533 goto err_return; 534 } 535 536 KASSERT(lnr == cheb->lnr); 537 538 err = chfs_scan_check_dirent_node(chmp, 539 cheb, buf, ofs - CHFS_NODE_HDR_SIZE); 540 if (err) 541 goto err_return; 542 543 break; 544 case CHFS_NODETYPE_DATA: 545 /* data node */ 546 len = sizeof(struct chfs_flash_data_node) - 547 CHFS_NODE_HDR_SIZE; 548 err = chfs_read_leb(chmp, 549 lnr, buf + CHFS_NODE_HDR_SIZE, 550 ofs, len, &retlen); 551 if (err) 552 goto err_return; 553 554 if (retlen != len) { 555 chfs_err("Error reading data node: read: %zu " 556 "instead of: %zu\n", len, retlen); 557 err = EIO; 558 goto err_return; 559 } 560 KASSERT(lnr == cheb->lnr); 561 err = chfs_scan_check_data_node(chmp, 562 cheb, buf, ofs - CHFS_NODE_HDR_SIZE); 563 if (err) 564 goto err_return; 565 566 break; 567 case CHFS_NODETYPE_PADDING: 568 /* padding node, set size and update dirty */ 569 nref = chfs_alloc_node_ref(cheb); 570 nref->nref_offset = ofs - CHFS_NODE_HDR_SIZE; 571 nref->nref_offset = CHFS_GET_OFS(nref->nref_offset) | 572 CHFS_OBSOLETE_NODE_MASK; 573 574 err = chfs_update_eb_dirty(chmp, cheb, 575 le32toh(nhdr->length)); 576 if (err) 577 goto err_return; 578 579 break; 580 default: 581 /* unknown node type, update dirty and skip */ 582 err = chfs_update_eb_dirty(chmp, cheb, 583 le32toh(nhdr->length)); 584 if (err) 585 goto err_return; 586 587 break; 588 } 589 ofs += le32toh(nhdr->length) - CHFS_NODE_HDR_SIZE; 590 } 591 592 KASSERT(cheb->used_size + cheb->free_size + cheb->dirty_size + 593 cheb->unchecked_size + cheb->wasted_size == chmp->chm_ebh->eb_size); 594 595 err = chfs_scan_classify_cheb(chmp, cheb); 596 /* FALLTHROUGH */ 597 err_return: 598 kmem_free(buf, CHFS_MAX_NODE_SIZE); 599 return err; 600 } 601