1/* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright �� 2001-2007 Red Hat, Inc. 5 * 6 * Created by David Woodhouse <dwmw2@infradead.org> 7 * 8 * For licensing information, see the file 'LICENCE' in this directory. 9 * 10 */ 11 12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13 14#include <linux/kernel.h> 15#include <linux/sched.h> 16#include <linux/slab.h> 17#include <linux/fs.h> 18#include <linux/crc32.h> 19#include <linux/pagemap.h> 20#include <linux/mtd/mtd.h> 21#include <linux/compiler.h> 22#include "nodelist.h" 23 24/* 25 * Check the data CRC of the node. 26 * 27 * Returns: 0 if the data CRC is correct; 28 * 1 - if incorrect; 29 * error code if an error occurred. 30 */ 31static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) 32{ 33 struct jffs2_raw_node_ref *ref = tn->fn->raw; 34 int err = 0, pointed = 0; 35 struct jffs2_eraseblock *jeb; 36 unsigned char *buffer; 37 uint32_t crc, ofs, len; 38 size_t retlen; 39 40 BUG_ON(tn->csize == 0); 41 42 /* Calculate how many bytes were already checked */ 43 ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode); 44 len = tn->csize; 45 46 if (jffs2_is_writebuffered(c)) { 47 int adj = ofs % c->wbuf_pagesize; 48 if (likely(adj)) 49 adj = c->wbuf_pagesize - adj; 50 51 if (adj >= tn->csize) { 52 dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n", 53 ref_offset(ref), tn->csize, ofs); 54 goto adj_acc; 55 } 56 57 ofs += adj; 58 len -= adj; 59 } 60 61 dbg_readinode("check node at %#08x, data length %u, partial CRC %#08x, correct CRC %#08x, data starts at %#08x, start checking from %#08x - %u bytes.\n", 62 ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len); 63 64#ifndef __ECOS 65 /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(), 66 * adding and jffs2_flash_read_end() interface. */ 67 err = mtd_point(c->mtd, ofs, len, &retlen, (void **)&buffer, NULL); 68 if (!err && retlen < len) { 69 JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize); 70 mtd_unpoint(c->mtd, ofs, retlen); 71 } else if (err) { 72 if (err != -EOPNOTSUPP) 73 JFFS2_WARNING("MTD point failed: error code %d.\n", err); 74 } else 75 pointed = 1; /* succefully pointed to device */ 76#endif 77 78 if (!pointed) { 79 buffer = kmalloc(len, GFP_KERNEL); 80 if (unlikely(!buffer)) 81 return -ENOMEM; 82 83 /* TODO: this is very frequent pattern, make it a separate 84 * routine */ 85 err = jffs2_flash_read(c, ofs, len, &retlen, buffer); 86 if (err) { 87 JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err); 88 goto free_out; 89 } 90 91 if (retlen != len) { 92 JFFS2_ERROR("short read at %#08x: %zd instead of %d.\n", ofs, retlen, len); 93 err = -EIO; 94 goto free_out; 95 } 96 } 97 98 /* Continue calculating CRC */ 99 crc = crc32(tn->partial_crc, buffer, len); 100 if(!pointed) 101 kfree(buffer); 102#ifndef __ECOS 103 else 104 mtd_unpoint(c->mtd, ofs, len); 105#endif 106 107 if (crc != tn->data_crc) { 108 JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", 109 ref_offset(ref), tn->data_crc, crc); 110 return 1; 111 } 112 113adj_acc: 114 jeb = &c->blocks[ref->flash_offset / c->sector_size]; 115 len = ref_totlen(c, jeb, ref); 116 /* If it should be REF_NORMAL, it'll get marked as such when 117 we build the fragtree, shortly. No need to worry about GC 118 moving it while it's marked REF_PRISTINE -- GC won't happen 119 till we've finished checking every inode anyway. */ 120 ref->flash_offset |= REF_PRISTINE; 121 /* 122 * Mark the node as having been checked and fix the 123 * accounting accordingly. 124 */ 125 spin_lock(&c->erase_completion_lock); 126 jeb->used_size += len; 127 jeb->unchecked_size -= len; 128 c->used_size += len; 129 c->unchecked_size -= len; 130 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 131 spin_unlock(&c->erase_completion_lock); 132 133 return 0; 134 135free_out: 136 if(!pointed) 137 kfree(buffer); 138#ifndef __ECOS 139 else 140 mtd_unpoint(c->mtd, ofs, len); 141#endif 142 return err; 143} 144 145/* 146 * Helper function for jffs2_add_older_frag_to_fragtree(). 147 * 148 * Checks the node if we are in the checking stage. 149 */ 150static int check_tn_node(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) 151{ 152 int ret; 153 154 BUG_ON(ref_obsolete(tn->fn->raw)); 155 156 /* We only check the data CRC of unchecked nodes */ 157 if (ref_flags(tn->fn->raw) != REF_UNCHECKED) 158 return 0; 159 160 dbg_readinode("check node %#04x-%#04x, phys offs %#08x\n", 161 tn->fn->ofs, tn->fn->ofs + tn->fn->size, ref_offset(tn->fn->raw)); 162 163 ret = check_node_data(c, tn); 164 if (unlikely(ret < 0)) { 165 JFFS2_ERROR("check_node_data() returned error: %d.\n", 166 ret); 167 } else if (unlikely(ret > 0)) { 168 dbg_readinode("CRC error, mark it obsolete.\n"); 169 jffs2_mark_node_obsolete(c, tn->fn->raw); 170 } 171 172 return ret; 173} 174 175static struct jffs2_tmp_dnode_info *jffs2_lookup_tn(struct rb_root *tn_root, uint32_t offset) 176{ 177 struct rb_node *next; 178 struct jffs2_tmp_dnode_info *tn = NULL; 179 180 dbg_readinode("root %p, offset %d\n", tn_root, offset); 181 182 next = tn_root->rb_node; 183 184 while (next) { 185 tn = rb_entry(next, struct jffs2_tmp_dnode_info, rb); 186 187 if (tn->fn->ofs < offset) 188 next = tn->rb.rb_right; 189 else if (tn->fn->ofs >= offset) 190 next = tn->rb.rb_left; 191 else 192 break; 193 } 194 195 return tn; 196} 197 198 199static void jffs2_kill_tn(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) 200{ 201 jffs2_mark_node_obsolete(c, tn->fn->raw); 202 jffs2_free_full_dnode(tn->fn); 203 jffs2_free_tmp_dnode_info(tn); 204} 205/* 206 * This function is used when we read an inode. Data nodes arrive in 207 * arbitrary order -- they may be older or newer than the nodes which 208 * are already in the tree. Where overlaps occur, the older node can 209 * be discarded as long as the newer passes the CRC check. We don't 210 * bother to keep track of holes in this rbtree, and neither do we deal 211 * with frags -- we can have multiple entries starting at the same 212 * offset, and the one with the smallest length will come first in the 213 * ordering. 214 * 215 * Returns 0 if the node was handled (including marking it obsolete) 216 * < 0 an if error occurred 217 */ 218static int jffs2_add_tn_to_tree(struct jffs2_sb_info *c, 219 struct jffs2_readinode_info *rii, 220 struct jffs2_tmp_dnode_info *tn) 221{ 222 uint32_t fn_end = tn->fn->ofs + tn->fn->size; 223 struct jffs2_tmp_dnode_info *this, *ptn; 224 225 dbg_readinode("insert fragment %#04x-%#04x, ver %u at %08x\n", tn->fn->ofs, fn_end, tn->version, ref_offset(tn->fn->raw)); 226 227 /* If a node has zero dsize, we only have to keep it if it might be the 228 node with highest version -- i.e. the one which will end up as f->metadata. 229 Note that such nodes won't be REF_UNCHECKED since there are no data to 230 check anyway. */ 231 if (!tn->fn->size) { 232 if (rii->mdata_tn) { 233 if (rii->mdata_tn->version < tn->version) { 234 /* We had a candidate mdata node already */ 235 dbg_readinode("kill old mdata with ver %d\n", rii->mdata_tn->version); 236 jffs2_kill_tn(c, rii->mdata_tn); 237 } else { 238 dbg_readinode("kill new mdata with ver %d (older than existing %d\n", 239 tn->version, rii->mdata_tn->version); 240 jffs2_kill_tn(c, tn); 241 return 0; 242 } 243 } 244 rii->mdata_tn = tn; 245 dbg_readinode("keep new mdata with ver %d\n", tn->version); 246 return 0; 247 } 248 249 /* Find the earliest node which _may_ be relevant to this one */ 250 this = jffs2_lookup_tn(&rii->tn_root, tn->fn->ofs); 251 if (this) { 252 /* If the node is coincident with another at a lower address, 253 back up until the other node is found. It may be relevant */ 254 while (this->overlapped) { 255 ptn = tn_prev(this); 256 if (!ptn) { 257 /* 258 * We killed a node which set the overlapped 259 * flags during the scan. Fix it up. 260 */ 261 this->overlapped = 0; 262 break; 263 } 264 this = ptn; 265 } 266 dbg_readinode("'this' found %#04x-%#04x (%s)\n", this->fn->ofs, this->fn->ofs + this->fn->size, this->fn ? "data" : "hole"); 267 } 268 269 while (this) { 270 if (this->fn->ofs > fn_end) 271 break; 272 dbg_readinode("Ponder this ver %d, 0x%x-0x%x\n", 273 this->version, this->fn->ofs, this->fn->size); 274 275 if (this->version == tn->version) { 276 /* Version number collision means REF_PRISTINE GC. Accept either of them 277 as long as the CRC is correct. Check the one we have already... */ 278 if (!check_tn_node(c, this)) { 279 /* The one we already had was OK. Keep it and throw away the new one */ 280 dbg_readinode("Like old node. Throw away new\n"); 281 jffs2_kill_tn(c, tn); 282 return 0; 283 } else { 284 /* Who cares if the new one is good; keep it for now anyway. */ 285 dbg_readinode("Like new node. Throw away old\n"); 286 rb_replace_node(&this->rb, &tn->rb, &rii->tn_root); 287 jffs2_kill_tn(c, this); 288 /* Same overlapping from in front and behind */ 289 return 0; 290 } 291 } 292 if (this->version < tn->version && 293 this->fn->ofs >= tn->fn->ofs && 294 this->fn->ofs + this->fn->size <= fn_end) { 295 /* New node entirely overlaps 'this' */ 296 if (check_tn_node(c, tn)) { 297 dbg_readinode("new node bad CRC\n"); 298 jffs2_kill_tn(c, tn); 299 return 0; 300 } 301 /* ... and is good. Kill 'this' and any subsequent nodes which are also overlapped */ 302 while (this && this->fn->ofs + this->fn->size <= fn_end) { 303 struct jffs2_tmp_dnode_info *next = tn_next(this); 304 if (this->version < tn->version) { 305 tn_erase(this, &rii->tn_root); 306 dbg_readinode("Kill overlapped ver %d, 0x%x-0x%x\n", 307 this->version, this->fn->ofs, 308 this->fn->ofs+this->fn->size); 309 jffs2_kill_tn(c, this); 310 } 311 this = next; 312 } 313 dbg_readinode("Done killing overlapped nodes\n"); 314 continue; 315 } 316 if (this->version > tn->version && 317 this->fn->ofs <= tn->fn->ofs && 318 this->fn->ofs+this->fn->size >= fn_end) { 319 /* New node entirely overlapped by 'this' */ 320 if (!check_tn_node(c, this)) { 321 dbg_readinode("Good CRC on old node. Kill new\n"); 322 jffs2_kill_tn(c, tn); 323 return 0; 324 } 325 /* ... but 'this' was bad. Replace it... */ 326 dbg_readinode("Bad CRC on old overlapping node. Kill it\n"); 327 tn_erase(this, &rii->tn_root); 328 jffs2_kill_tn(c, this); 329 break; 330 } 331 332 this = tn_next(this); 333 } 334 335 /* We neither completely obsoleted nor were completely 336 obsoleted by an earlier node. Insert into the tree */ 337 { 338 struct rb_node *parent; 339 struct rb_node **link = &rii->tn_root.rb_node; 340 struct jffs2_tmp_dnode_info *insert_point = NULL; 341 342 while (*link) { 343 parent = *link; 344 insert_point = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); 345 if (tn->fn->ofs > insert_point->fn->ofs) 346 link = &insert_point->rb.rb_right; 347 else if (tn->fn->ofs < insert_point->fn->ofs || 348 tn->fn->size < insert_point->fn->size) 349 link = &insert_point->rb.rb_left; 350 else 351 link = &insert_point->rb.rb_right; 352 } 353 rb_link_node(&tn->rb, &insert_point->rb, link); 354 rb_insert_color(&tn->rb, &rii->tn_root); 355 } 356 357 /* If there's anything behind that overlaps us, note it */ 358 this = tn_prev(tn); 359 if (this) { 360 while (1) { 361 if (this->fn->ofs + this->fn->size > tn->fn->ofs) { 362 dbg_readinode("Node is overlapped by %p (v %d, 0x%x-0x%x)\n", 363 this, this->version, this->fn->ofs, 364 this->fn->ofs+this->fn->size); 365 tn->overlapped = 1; 366 break; 367 } 368 if (!this->overlapped) 369 break; 370 371 ptn = tn_prev(this); 372 if (!ptn) { 373 /* 374 * We killed a node which set the overlapped 375 * flags during the scan. Fix it up. 376 */ 377 this->overlapped = 0; 378 break; 379 } 380 this = ptn; 381 } 382 } 383 384 /* If the new node overlaps anything ahead, note it */ 385 this = tn_next(tn); 386 while (this && this->fn->ofs < fn_end) { 387 this->overlapped = 1; 388 dbg_readinode("Node ver %d, 0x%x-0x%x is overlapped\n", 389 this->version, this->fn->ofs, 390 this->fn->ofs+this->fn->size); 391 this = tn_next(this); 392 } 393 return 0; 394} 395 396/* Trivial function to remove the last node in the tree. Which by definition 397 has no right-hand child ��� so can be removed just by making its left-hand 398 child (if any) take its place under its parent. Since this is only done 399 when we're consuming the whole tree, there's no need to use rb_erase() 400 and let it worry about adjusting colours and balancing the tree. That 401 would just be a waste of time. */ 402static void eat_last(struct rb_root *root, struct rb_node *node) 403{ 404 struct rb_node *parent = rb_parent(node); 405 struct rb_node **link; 406 407 /* LAST! */ 408 BUG_ON(node->rb_right); 409 410 if (!parent) 411 link = &root->rb_node; 412 else if (node == parent->rb_left) 413 link = &parent->rb_left; 414 else 415 link = &parent->rb_right; 416 417 *link = node->rb_left; 418 if (node->rb_left) 419 node->rb_left->__rb_parent_color = node->__rb_parent_color; 420} 421 422/* We put the version tree in reverse order, so we can use the same eat_last() 423 function that we use to consume the tmpnode tree (tn_root). */ 424static void ver_insert(struct rb_root *ver_root, struct jffs2_tmp_dnode_info *tn) 425{ 426 struct rb_node **link = &ver_root->rb_node; 427 struct rb_node *parent = NULL; 428 struct jffs2_tmp_dnode_info *this_tn; 429 430 while (*link) { 431 parent = *link; 432 this_tn = rb_entry(parent, struct jffs2_tmp_dnode_info, rb); 433 434 if (tn->version > this_tn->version) 435 link = &parent->rb_left; 436 else 437 link = &parent->rb_right; 438 } 439 dbg_readinode("Link new node at %p (root is %p)\n", link, ver_root); 440 rb_link_node(&tn->rb, parent, link); 441 rb_insert_color(&tn->rb, ver_root); 442} 443 444/* Build final, normal fragtree from tn tree. It doesn't matter which order 445 we add nodes to the real fragtree, as long as they don't overlap. And 446 having thrown away the majority of overlapped nodes as we went, there 447 really shouldn't be many sets of nodes which do overlap. If we start at 448 the end, we can use the overlap markers -- we can just eat nodes which 449 aren't overlapped, and when we encounter nodes which _do_ overlap we 450 sort them all into a temporary tree in version order before replaying them. */ 451static int jffs2_build_inode_fragtree(struct jffs2_sb_info *c, 452 struct jffs2_inode_info *f, 453 struct jffs2_readinode_info *rii) 454{ 455 struct jffs2_tmp_dnode_info *pen, *last, *this; 456 struct rb_root ver_root = RB_ROOT; 457 uint32_t high_ver = 0; 458 459 if (rii->mdata_tn) { 460 dbg_readinode("potential mdata is ver %d at %p\n", rii->mdata_tn->version, rii->mdata_tn); 461 high_ver = rii->mdata_tn->version; 462 rii->latest_ref = rii->mdata_tn->fn->raw; 463 } 464#ifdef JFFS2_DBG_READINODE_MESSAGES 465 this = tn_last(&rii->tn_root); 466 while (this) { 467 dbg_readinode("tn %p ver %d range 0x%x-0x%x ov %d\n", this, this->version, this->fn->ofs, 468 this->fn->ofs+this->fn->size, this->overlapped); 469 this = tn_prev(this); 470 } 471#endif 472 pen = tn_last(&rii->tn_root); 473 while ((last = pen)) { 474 pen = tn_prev(last); 475 476 eat_last(&rii->tn_root, &last->rb); 477 ver_insert(&ver_root, last); 478 479 if (unlikely(last->overlapped)) { 480 if (pen) 481 continue; 482 /* 483 * We killed a node which set the overlapped 484 * flags during the scan. Fix it up. 485 */ 486 last->overlapped = 0; 487 } 488 489 /* Now we have a bunch of nodes in reverse version 490 order, in the tree at ver_root. Most of the time, 491 there'll actually be only one node in the 'tree', 492 in fact. */ 493 this = tn_last(&ver_root); 494 495 while (this) { 496 struct jffs2_tmp_dnode_info *vers_next; 497 int ret; 498 vers_next = tn_prev(this); 499 eat_last(&ver_root, &this->rb); 500 if (check_tn_node(c, this)) { 501 dbg_readinode("node ver %d, 0x%x-0x%x failed CRC\n", 502 this->version, this->fn->ofs, 503 this->fn->ofs+this->fn->size); 504 jffs2_kill_tn(c, this); 505 } else { 506 if (this->version > high_ver) { 507 /* Note that this is different from the other 508 highest_version, because this one is only 509 counting _valid_ nodes which could give the 510 latest inode metadata */ 511 high_ver = this->version; 512 rii->latest_ref = this->fn->raw; 513 } 514 dbg_readinode("Add %p (v %d, 0x%x-0x%x, ov %d) to fragtree\n", 515 this, this->version, this->fn->ofs, 516 this->fn->ofs+this->fn->size, this->overlapped); 517 518 ret = jffs2_add_full_dnode_to_inode(c, f, this->fn); 519 if (ret) { 520 /* Free the nodes in vers_root; let the caller 521 deal with the rest */ 522 JFFS2_ERROR("Add node to tree failed %d\n", ret); 523 while (1) { 524 vers_next = tn_prev(this); 525 if (check_tn_node(c, this)) 526 jffs2_mark_node_obsolete(c, this->fn->raw); 527 jffs2_free_full_dnode(this->fn); 528 jffs2_free_tmp_dnode_info(this); 529 this = vers_next; 530 if (!this) 531 break; 532 eat_last(&ver_root, &vers_next->rb); 533 } 534 return ret; 535 } 536 jffs2_free_tmp_dnode_info(this); 537 } 538 this = vers_next; 539 } 540 } 541 return 0; 542} 543 544static void jffs2_free_tmp_dnode_info_list(struct rb_root *list) 545{ 546 struct jffs2_tmp_dnode_info *tn, *next; 547 548 rbtree_postorder_for_each_entry_safe(tn, next, list, rb) { 549 jffs2_free_full_dnode(tn->fn); 550 jffs2_free_tmp_dnode_info(tn); 551 } 552 553 *list = RB_ROOT; 554} 555 556static void jffs2_free_full_dirent_list(struct jffs2_full_dirent *fd) 557{ 558 struct jffs2_full_dirent *next; 559 560 while (fd) { 561 next = fd->next; 562 jffs2_free_full_dirent(fd); 563 fd = next; 564 } 565} 566 567/* Returns first valid node after 'ref'. May return 'ref' */ 568static struct jffs2_raw_node_ref *jffs2_first_valid_node(struct jffs2_raw_node_ref *ref) 569{ 570 while (ref && ref->next_in_ino) { 571 if (!ref_obsolete(ref)) 572 return ref; 573 dbg_noderef("node at 0x%08x is obsoleted. Ignoring.\n", ref_offset(ref)); 574 ref = ref->next_in_ino; 575 } 576 return NULL; 577} 578 579/* 580 * Helper function for jffs2_get_inode_nodes(). 581 * It is called every time an directory entry node is found. 582 * 583 * Returns: 0 on success; 584 * negative error code on failure. 585 */ 586static inline int read_direntry(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, 587 struct jffs2_raw_dirent *rd, size_t read, 588 struct jffs2_readinode_info *rii) 589{ 590 struct jffs2_full_dirent *fd; 591 uint32_t crc; 592 593 /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ 594 BUG_ON(ref_obsolete(ref)); 595 596 crc = crc32(0, rd, sizeof(*rd) - 8); 597 if (unlikely(crc != je32_to_cpu(rd->node_crc))) { 598 JFFS2_NOTICE("header CRC failed on dirent node at %#08x: read %#08x, calculated %#08x\n", 599 ref_offset(ref), je32_to_cpu(rd->node_crc), crc); 600 jffs2_mark_node_obsolete(c, ref); 601 return 0; 602 } 603 604 /* If we've never checked the CRCs on this node, check them now */ 605 if (ref_flags(ref) == REF_UNCHECKED) { 606 struct jffs2_eraseblock *jeb; 607 int len; 608 609 /* Sanity check */ 610 if (unlikely(PAD((rd->nsize + sizeof(*rd))) != PAD(je32_to_cpu(rd->totlen)))) { 611 JFFS2_ERROR("illegal nsize in node at %#08x: nsize %#02x, totlen %#04x\n", 612 ref_offset(ref), rd->nsize, je32_to_cpu(rd->totlen)); 613 jffs2_mark_node_obsolete(c, ref); 614 return 0; 615 } 616 617 jeb = &c->blocks[ref->flash_offset / c->sector_size]; 618 len = ref_totlen(c, jeb, ref); 619 620 spin_lock(&c->erase_completion_lock); 621 jeb->used_size += len; 622 jeb->unchecked_size -= len; 623 c->used_size += len; 624 c->unchecked_size -= len; 625 ref->flash_offset = ref_offset(ref) | dirent_node_state(rd); 626 spin_unlock(&c->erase_completion_lock); 627 } 628 629 fd = jffs2_alloc_full_dirent(rd->nsize + 1); 630 if (unlikely(!fd)) 631 return -ENOMEM; 632 633 fd->raw = ref; 634 fd->version = je32_to_cpu(rd->version); 635 fd->ino = je32_to_cpu(rd->ino); 636 fd->type = rd->type; 637 638 if (fd->version > rii->highest_version) 639 rii->highest_version = fd->version; 640 641 /* Pick out the mctime of the latest dirent */ 642 if(fd->version > rii->mctime_ver && je32_to_cpu(rd->mctime)) { 643 rii->mctime_ver = fd->version; 644 rii->latest_mctime = je32_to_cpu(rd->mctime); 645 } 646 647 /* 648 * Copy as much of the name as possible from the raw 649 * dirent we've already read from the flash. 650 */ 651 if (read > sizeof(*rd)) 652 memcpy(&fd->name[0], &rd->name[0], 653 min_t(uint32_t, rd->nsize, (read - sizeof(*rd)) )); 654 655 /* Do we need to copy any more of the name directly from the flash? */ 656 if (rd->nsize + sizeof(*rd) > read) { 657 /* FIXME: point() */ 658 int err; 659 int already = read - sizeof(*rd); 660 661 err = jffs2_flash_read(c, (ref_offset(ref)) + read, 662 rd->nsize - already, &read, &fd->name[already]); 663 if (unlikely(read != rd->nsize - already) && likely(!err)) { 664 jffs2_free_full_dirent(fd); 665 JFFS2_ERROR("short read: wanted %d bytes, got %zd\n", 666 rd->nsize - already, read); 667 return -EIO; 668 } 669 670 if (unlikely(err)) { 671 JFFS2_ERROR("read remainder of name: error %d\n", err); 672 jffs2_free_full_dirent(fd); 673 return -EIO; 674 } 675 } 676 677 fd->nhash = full_name_hash(fd->name, rd->nsize); 678 fd->next = NULL; 679 fd->name[rd->nsize] = '\0'; 680 681 /* 682 * Wheee. We now have a complete jffs2_full_dirent structure, with 683 * the name in it and everything. Link it into the list 684 */ 685 jffs2_add_fd_to_list(c, fd, &rii->fds); 686 687 return 0; 688} 689 690/* 691 * Helper function for jffs2_get_inode_nodes(). 692 * It is called every time an inode node is found. 693 * 694 * Returns: 0 on success (possibly after marking a bad node obsolete); 695 * negative error code on failure. 696 */ 697static inline int read_dnode(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, 698 struct jffs2_raw_inode *rd, int rdlen, 699 struct jffs2_readinode_info *rii) 700{ 701 struct jffs2_tmp_dnode_info *tn; 702 uint32_t len, csize; 703 int ret = 0; 704 uint32_t crc; 705 706 /* Obsoleted. This cannot happen, surely? dwmw2 20020308 */ 707 BUG_ON(ref_obsolete(ref)); 708 709 crc = crc32(0, rd, sizeof(*rd) - 8); 710 if (unlikely(crc != je32_to_cpu(rd->node_crc))) { 711 JFFS2_NOTICE("node CRC failed on dnode at %#08x: read %#08x, calculated %#08x\n", 712 ref_offset(ref), je32_to_cpu(rd->node_crc), crc); 713 jffs2_mark_node_obsolete(c, ref); 714 return 0; 715 } 716 717 tn = jffs2_alloc_tmp_dnode_info(); 718 if (!tn) { 719 JFFS2_ERROR("failed to allocate tn (%zu bytes).\n", sizeof(*tn)); 720 return -ENOMEM; 721 } 722 723 tn->partial_crc = 0; 724 csize = je32_to_cpu(rd->csize); 725 726 /* If we've never checked the CRCs on this node, check them now */ 727 if (ref_flags(ref) == REF_UNCHECKED) { 728 729 /* Sanity checks */ 730 if (unlikely(je32_to_cpu(rd->offset) > je32_to_cpu(rd->isize)) || 731 unlikely(PAD(je32_to_cpu(rd->csize) + sizeof(*rd)) != PAD(je32_to_cpu(rd->totlen)))) { 732 JFFS2_WARNING("inode node header CRC is corrupted at %#08x\n", ref_offset(ref)); 733 jffs2_dbg_dump_node(c, ref_offset(ref)); 734 jffs2_mark_node_obsolete(c, ref); 735 goto free_out; 736 } 737 738 if (jffs2_is_writebuffered(c) && csize != 0) { 739 /* At this point we are supposed to check the data CRC 740 * of our unchecked node. But thus far, we do not 741 * know whether the node is valid or obsolete. To 742 * figure this out, we need to walk all the nodes of 743 * the inode and build the inode fragtree. We don't 744 * want to spend time checking data of nodes which may 745 * later be found to be obsolete. So we put off the full 746 * data CRC checking until we have read all the inode 747 * nodes and have started building the fragtree. 748 * 749 * The fragtree is being built starting with nodes 750 * having the highest version number, so we'll be able 751 * to detect whether a node is valid (i.e., it is not 752 * overlapped by a node with higher version) or not. 753 * And we'll be able to check only those nodes, which 754 * are not obsolete. 755 * 756 * Of course, this optimization only makes sense in case 757 * of NAND flashes (or other flashes with 758 * !jffs2_can_mark_obsolete()), since on NOR flashes 759 * nodes are marked obsolete physically. 760 * 761 * Since NAND flashes (or other flashes with 762 * jffs2_is_writebuffered(c)) are anyway read by 763 * fractions of c->wbuf_pagesize, and we have just read 764 * the node header, it is likely that the starting part 765 * of the node data is also read when we read the 766 * header. So we don't mind to check the CRC of the 767 * starting part of the data of the node now, and check 768 * the second part later (in jffs2_check_node_data()). 769 * Of course, we will not need to re-read and re-check 770 * the NAND page which we have just read. This is why we 771 * read the whole NAND page at jffs2_get_inode_nodes(), 772 * while we needed only the node header. 773 */ 774 unsigned char *buf; 775 776 /* 'buf' will point to the start of data */ 777 buf = (unsigned char *)rd + sizeof(*rd); 778 /* len will be the read data length */ 779 len = min_t(uint32_t, rdlen - sizeof(*rd), csize); 780 tn->partial_crc = crc32(0, buf, len); 781 782 dbg_readinode("Calculates CRC (%#08x) for %d bytes, csize %d\n", tn->partial_crc, len, csize); 783 784 /* If we actually calculated the whole data CRC 785 * and it is wrong, drop the node. */ 786 if (len >= csize && unlikely(tn->partial_crc != je32_to_cpu(rd->data_crc))) { 787 JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", 788 ref_offset(ref), tn->partial_crc, je32_to_cpu(rd->data_crc)); 789 jffs2_mark_node_obsolete(c, ref); 790 goto free_out; 791 } 792 793 } else if (csize == 0) { 794 /* 795 * We checked the header CRC. If the node has no data, adjust 796 * the space accounting now. For other nodes this will be done 797 * later either when the node is marked obsolete or when its 798 * data is checked. 799 */ 800 struct jffs2_eraseblock *jeb; 801 802 dbg_readinode("the node has no data.\n"); 803 jeb = &c->blocks[ref->flash_offset / c->sector_size]; 804 len = ref_totlen(c, jeb, ref); 805 806 spin_lock(&c->erase_completion_lock); 807 jeb->used_size += len; 808 jeb->unchecked_size -= len; 809 c->used_size += len; 810 c->unchecked_size -= len; 811 ref->flash_offset = ref_offset(ref) | REF_NORMAL; 812 spin_unlock(&c->erase_completion_lock); 813 } 814 } 815 816 tn->fn = jffs2_alloc_full_dnode(); 817 if (!tn->fn) { 818 JFFS2_ERROR("alloc fn failed\n"); 819 ret = -ENOMEM; 820 goto free_out; 821 } 822 823 tn->version = je32_to_cpu(rd->version); 824 tn->fn->ofs = je32_to_cpu(rd->offset); 825 tn->data_crc = je32_to_cpu(rd->data_crc); 826 tn->csize = csize; 827 tn->fn->raw = ref; 828 tn->overlapped = 0; 829 830 if (tn->version > rii->highest_version) 831 rii->highest_version = tn->version; 832 833 /* There was a bug where we wrote hole nodes out with 834 csize/dsize swapped. Deal with it */ 835 if (rd->compr == JFFS2_COMPR_ZERO && !je32_to_cpu(rd->dsize) && csize) 836 tn->fn->size = csize; 837 else // normal case... 838 tn->fn->size = je32_to_cpu(rd->dsize); 839 840 dbg_readinode2("dnode @%08x: ver %u, offset %#04x, dsize %#04x, csize %#04x\n", 841 ref_offset(ref), je32_to_cpu(rd->version), 842 je32_to_cpu(rd->offset), je32_to_cpu(rd->dsize), csize); 843 844 ret = jffs2_add_tn_to_tree(c, rii, tn); 845 846 if (ret) { 847 jffs2_free_full_dnode(tn->fn); 848 free_out: 849 jffs2_free_tmp_dnode_info(tn); 850 return ret; 851 } 852#ifdef JFFS2_DBG_READINODE2_MESSAGES 853 dbg_readinode2("After adding ver %d:\n", je32_to_cpu(rd->version)); 854 tn = tn_first(&rii->tn_root); 855 while (tn) { 856 dbg_readinode2("%p: v %d r 0x%x-0x%x ov %d\n", 857 tn, tn->version, tn->fn->ofs, 858 tn->fn->ofs+tn->fn->size, tn->overlapped); 859 tn = tn_next(tn); 860 } 861#endif 862 return 0; 863} 864 865/* 866 * Helper function for jffs2_get_inode_nodes(). 867 * It is called every time an unknown node is found. 868 * 869 * Returns: 0 on success; 870 * negative error code on failure. 871 */ 872static inline int read_unknown(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, struct jffs2_unknown_node *un) 873{ 874 /* We don't mark unknown nodes as REF_UNCHECKED */ 875 if (ref_flags(ref) == REF_UNCHECKED) { 876 JFFS2_ERROR("REF_UNCHECKED but unknown node at %#08x\n", 877 ref_offset(ref)); 878 JFFS2_ERROR("Node is {%04x,%04x,%08x,%08x}. Please report this error.\n", 879 je16_to_cpu(un->magic), je16_to_cpu(un->nodetype), 880 je32_to_cpu(un->totlen), je32_to_cpu(un->hdr_crc)); 881 jffs2_mark_node_obsolete(c, ref); 882 return 0; 883 } 884 885 un->nodetype = cpu_to_je16(JFFS2_NODE_ACCURATE | je16_to_cpu(un->nodetype)); 886 887 switch(je16_to_cpu(un->nodetype) & JFFS2_COMPAT_MASK) { 888 889 case JFFS2_FEATURE_INCOMPAT: 890 JFFS2_ERROR("unknown INCOMPAT nodetype %#04X at %#08x\n", 891 je16_to_cpu(un->nodetype), ref_offset(ref)); 892 /* EEP */ 893 BUG(); 894 break; 895 896 case JFFS2_FEATURE_ROCOMPAT: 897 JFFS2_ERROR("unknown ROCOMPAT nodetype %#04X at %#08x\n", 898 je16_to_cpu(un->nodetype), ref_offset(ref)); 899 BUG_ON(!(c->flags & JFFS2_SB_FLAG_RO)); 900 break; 901 902 case JFFS2_FEATURE_RWCOMPAT_COPY: 903 JFFS2_NOTICE("unknown RWCOMPAT_COPY nodetype %#04X at %#08x\n", 904 je16_to_cpu(un->nodetype), ref_offset(ref)); 905 break; 906 907 case JFFS2_FEATURE_RWCOMPAT_DELETE: 908 JFFS2_NOTICE("unknown RWCOMPAT_DELETE nodetype %#04X at %#08x\n", 909 je16_to_cpu(un->nodetype), ref_offset(ref)); 910 jffs2_mark_node_obsolete(c, ref); 911 return 0; 912 } 913 914 return 0; 915} 916 917/* 918 * Helper function for jffs2_get_inode_nodes(). 919 * The function detects whether more data should be read and reads it if yes. 920 * 921 * Returns: 0 on success; 922 * negative error code on failure. 923 */ 924static int read_more(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref, 925 int needed_len, int *rdlen, unsigned char *buf) 926{ 927 int err, to_read = needed_len - *rdlen; 928 size_t retlen; 929 uint32_t offs; 930 931 if (jffs2_is_writebuffered(c)) { 932 int rem = to_read % c->wbuf_pagesize; 933 934 if (rem) 935 to_read += c->wbuf_pagesize - rem; 936 } 937 938 /* We need to read more data */ 939 offs = ref_offset(ref) + *rdlen; 940 941 dbg_readinode("read more %d bytes\n", to_read); 942 943 err = jffs2_flash_read(c, offs, to_read, &retlen, buf + *rdlen); 944 if (err) { 945 JFFS2_ERROR("can not read %d bytes from 0x%08x, " 946 "error code: %d.\n", to_read, offs, err); 947 return err; 948 } 949 950 if (retlen < to_read) { 951 JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n", 952 offs, retlen, to_read); 953 return -EIO; 954 } 955 956 *rdlen += to_read; 957 return 0; 958} 959 960/* Get tmp_dnode_info and full_dirent for all non-obsolete nodes associated 961 with this ino. Perform a preliminary ordering on data nodes, throwing away 962 those which are completely obsoleted by newer ones. The na��ve approach we 963 use to take of just returning them _all_ in version order will cause us to 964 run out of memory in certain degenerate cases. */ 965static int jffs2_get_inode_nodes(struct jffs2_sb_info *c, struct jffs2_inode_info *f, 966 struct jffs2_readinode_info *rii) 967{ 968 struct jffs2_raw_node_ref *ref, *valid_ref; 969 unsigned char *buf = NULL; 970 union jffs2_node_union *node; 971 size_t retlen; 972 int len, err; 973 974 rii->mctime_ver = 0; 975 976 dbg_readinode("ino #%u\n", f->inocache->ino); 977 978 /* FIXME: in case of NOR and available ->point() this 979 * needs to be fixed. */ 980 len = sizeof(union jffs2_node_union) + c->wbuf_pagesize; 981 buf = kmalloc(len, GFP_KERNEL); 982 if (!buf) 983 return -ENOMEM; 984 985 spin_lock(&c->erase_completion_lock); 986 valid_ref = jffs2_first_valid_node(f->inocache->nodes); 987 if (!valid_ref && f->inocache->ino != 1) 988 JFFS2_WARNING("Eep. No valid nodes for ino #%u.\n", f->inocache->ino); 989 while (valid_ref) { 990 /* We can hold a pointer to a non-obsolete node without the spinlock, 991 but _obsolete_ nodes may disappear at any time, if the block 992 they're in gets erased. So if we mark 'ref' obsolete while we're 993 not holding the lock, it can go away immediately. For that reason, 994 we find the next valid node first, before processing 'ref'. 995 */ 996 ref = valid_ref; 997 valid_ref = jffs2_first_valid_node(ref->next_in_ino); 998 spin_unlock(&c->erase_completion_lock); 999 1000 cond_resched(); 1001 1002 /* 1003 * At this point we don't know the type of the node we're going 1004 * to read, so we do not know the size of its header. In order 1005 * to minimize the amount of flash IO we assume the header is 1006 * of size = JFFS2_MIN_NODE_HEADER. 1007 */ 1008 len = JFFS2_MIN_NODE_HEADER; 1009 if (jffs2_is_writebuffered(c)) { 1010 int end, rem; 1011 1012 /* 1013 * We are about to read JFFS2_MIN_NODE_HEADER bytes, 1014 * but this flash has some minimal I/O unit. It is 1015 * possible that we'll need to read more soon, so read 1016 * up to the next min. I/O unit, in order not to 1017 * re-read the same min. I/O unit twice. 1018 */ 1019 end = ref_offset(ref) + len; 1020 rem = end % c->wbuf_pagesize; 1021 if (rem) 1022 end += c->wbuf_pagesize - rem; 1023 len = end - ref_offset(ref); 1024 } 1025 1026 dbg_readinode("read %d bytes at %#08x(%d).\n", len, ref_offset(ref), ref_flags(ref)); 1027 1028 /* FIXME: point() */ 1029 err = jffs2_flash_read(c, ref_offset(ref), len, &retlen, buf); 1030 if (err) { 1031 JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ref_offset(ref), err); 1032 goto free_out; 1033 } 1034 1035 if (retlen < len) { 1036 JFFS2_ERROR("short read at %#08x: %zu instead of %d.\n", ref_offset(ref), retlen, len); 1037 err = -EIO; 1038 goto free_out; 1039 } 1040 1041 node = (union jffs2_node_union *)buf; 1042 1043 /* No need to mask in the valid bit; it shouldn't be invalid */ 1044 if (je32_to_cpu(node->u.hdr_crc) != crc32(0, node, sizeof(node->u)-4)) { 1045 JFFS2_NOTICE("Node header CRC failed at %#08x. {%04x,%04x,%08x,%08x}\n", 1046 ref_offset(ref), je16_to_cpu(node->u.magic), 1047 je16_to_cpu(node->u.nodetype), 1048 je32_to_cpu(node->u.totlen), 1049 je32_to_cpu(node->u.hdr_crc)); 1050 jffs2_dbg_dump_node(c, ref_offset(ref)); 1051 jffs2_mark_node_obsolete(c, ref); 1052 goto cont; 1053 } 1054 if (je16_to_cpu(node->u.magic) != JFFS2_MAGIC_BITMASK) { 1055 /* Not a JFFS2 node, whinge and move on */ 1056 JFFS2_NOTICE("Wrong magic bitmask 0x%04x in node header at %#08x.\n", 1057 je16_to_cpu(node->u.magic), ref_offset(ref)); 1058 jffs2_mark_node_obsolete(c, ref); 1059 goto cont; 1060 } 1061 1062 switch (je16_to_cpu(node->u.nodetype)) { 1063 1064 case JFFS2_NODETYPE_DIRENT: 1065 1066 if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_dirent) && 1067 len < sizeof(struct jffs2_raw_dirent)) { 1068 err = read_more(c, ref, sizeof(struct jffs2_raw_dirent), &len, buf); 1069 if (unlikely(err)) 1070 goto free_out; 1071 } 1072 1073 err = read_direntry(c, ref, &node->d, retlen, rii); 1074 if (unlikely(err)) 1075 goto free_out; 1076 1077 break; 1078 1079 case JFFS2_NODETYPE_INODE: 1080 1081 if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_raw_inode) && 1082 len < sizeof(struct jffs2_raw_inode)) { 1083 err = read_more(c, ref, sizeof(struct jffs2_raw_inode), &len, buf); 1084 if (unlikely(err)) 1085 goto free_out; 1086 } 1087 1088 err = read_dnode(c, ref, &node->i, len, rii); 1089 if (unlikely(err)) 1090 goto free_out; 1091 1092 break; 1093 1094 default: 1095 if (JFFS2_MIN_NODE_HEADER < sizeof(struct jffs2_unknown_node) && 1096 len < sizeof(struct jffs2_unknown_node)) { 1097 err = read_more(c, ref, sizeof(struct jffs2_unknown_node), &len, buf); 1098 if (unlikely(err)) 1099 goto free_out; 1100 } 1101 1102 err = read_unknown(c, ref, &node->u); 1103 if (unlikely(err)) 1104 goto free_out; 1105 1106 } 1107 cont: 1108 spin_lock(&c->erase_completion_lock); 1109 } 1110 1111 spin_unlock(&c->erase_completion_lock); 1112 kfree(buf); 1113 1114 f->highest_version = rii->highest_version; 1115 1116 dbg_readinode("nodes of inode #%u were read, the highest version is %u, latest_mctime %u, mctime_ver %u.\n", 1117 f->inocache->ino, rii->highest_version, rii->latest_mctime, 1118 rii->mctime_ver); 1119 return 0; 1120 1121 free_out: 1122 jffs2_free_tmp_dnode_info_list(&rii->tn_root); 1123 jffs2_free_full_dirent_list(rii->fds); 1124 rii->fds = NULL; 1125 kfree(buf); 1126 return err; 1127} 1128 1129static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c, 1130 struct jffs2_inode_info *f, 1131 struct jffs2_raw_inode *latest_node) 1132{ 1133 struct jffs2_readinode_info rii; 1134 uint32_t crc, new_size; 1135 size_t retlen; 1136 int ret; 1137 1138 dbg_readinode("ino #%u pino/nlink is %d\n", f->inocache->ino, 1139 f->inocache->pino_nlink); 1140 1141 memset(&rii, 0, sizeof(rii)); 1142 1143 /* Grab all nodes relevant to this ino */ 1144 ret = jffs2_get_inode_nodes(c, f, &rii); 1145 1146 if (ret) { 1147 JFFS2_ERROR("cannot read nodes for ino %u, returned error is %d\n", f->inocache->ino, ret); 1148 if (f->inocache->state == INO_STATE_READING) 1149 jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); 1150 return ret; 1151 } 1152 1153 ret = jffs2_build_inode_fragtree(c, f, &rii); 1154 if (ret) { 1155 JFFS2_ERROR("Failed to build final fragtree for inode #%u: error %d\n", 1156 f->inocache->ino, ret); 1157 if (f->inocache->state == INO_STATE_READING) 1158 jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); 1159 jffs2_free_tmp_dnode_info_list(&rii.tn_root); 1160 /* FIXME: We could at least crc-check them all */ 1161 if (rii.mdata_tn) { 1162 jffs2_free_full_dnode(rii.mdata_tn->fn); 1163 jffs2_free_tmp_dnode_info(rii.mdata_tn); 1164 rii.mdata_tn = NULL; 1165 } 1166 return ret; 1167 } 1168 1169 if (rii.mdata_tn) { 1170 if (rii.mdata_tn->fn->raw == rii.latest_ref) { 1171 f->metadata = rii.mdata_tn->fn; 1172 jffs2_free_tmp_dnode_info(rii.mdata_tn); 1173 } else { 1174 jffs2_kill_tn(c, rii.mdata_tn); 1175 } 1176 rii.mdata_tn = NULL; 1177 } 1178 1179 f->dents = rii.fds; 1180 1181 jffs2_dbg_fragtree_paranoia_check_nolock(f); 1182 1183 if (unlikely(!rii.latest_ref)) { 1184 /* No data nodes for this inode. */ 1185 if (f->inocache->ino != 1) { 1186 JFFS2_WARNING("no data nodes found for ino #%u\n", f->inocache->ino); 1187 if (!rii.fds) { 1188 if (f->inocache->state == INO_STATE_READING) 1189 jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); 1190 return -EIO; 1191 } 1192 JFFS2_NOTICE("but it has children so we fake some modes for it\n"); 1193 } 1194 latest_node->mode = cpu_to_jemode(S_IFDIR|S_IRUGO|S_IWUSR|S_IXUGO); 1195 latest_node->version = cpu_to_je32(0); 1196 latest_node->atime = latest_node->ctime = latest_node->mtime = cpu_to_je32(0); 1197 latest_node->isize = cpu_to_je32(0); 1198 latest_node->gid = cpu_to_je16(0); 1199 latest_node->uid = cpu_to_je16(0); 1200 if (f->inocache->state == INO_STATE_READING) 1201 jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); 1202 return 0; 1203 } 1204 1205 ret = jffs2_flash_read(c, ref_offset(rii.latest_ref), sizeof(*latest_node), &retlen, (void *)latest_node); 1206 if (ret || retlen != sizeof(*latest_node)) { 1207 JFFS2_ERROR("failed to read from flash: error %d, %zd of %zd bytes read\n", 1208 ret, retlen, sizeof(*latest_node)); 1209 /* FIXME: If this fails, there seems to be a memory leak. Find it. */ 1210 return ret ? ret : -EIO; 1211 } 1212 1213 crc = crc32(0, latest_node, sizeof(*latest_node)-8); 1214 if (crc != je32_to_cpu(latest_node->node_crc)) { 1215 JFFS2_ERROR("CRC failed for read_inode of inode %u at physical location 0x%x\n", 1216 f->inocache->ino, ref_offset(rii.latest_ref)); 1217 return -EIO; 1218 } 1219 1220 switch(jemode_to_cpu(latest_node->mode) & S_IFMT) { 1221 case S_IFDIR: 1222 if (rii.mctime_ver > je32_to_cpu(latest_node->version)) { 1223 /* The times in the latest_node are actually older than 1224 mctime in the latest dirent. Cheat. */ 1225 latest_node->ctime = latest_node->mtime = cpu_to_je32(rii.latest_mctime); 1226 } 1227 break; 1228 1229 1230 case S_IFREG: 1231 /* If it was a regular file, truncate it to the latest node's isize */ 1232 new_size = jffs2_truncate_fragtree(c, &f->fragtree, je32_to_cpu(latest_node->isize)); 1233 if (new_size != je32_to_cpu(latest_node->isize)) { 1234 JFFS2_WARNING("Truncating ino #%u to %d bytes failed because it only had %d bytes to start with!\n", 1235 f->inocache->ino, je32_to_cpu(latest_node->isize), new_size); 1236 latest_node->isize = cpu_to_je32(new_size); 1237 } 1238 break; 1239 1240 case S_IFLNK: 1241 /* Hack to work around broken isize in old symlink code. 1242 Remove this when dwmw2 comes to his senses and stops 1243 symlinks from being an entirely gratuitous special 1244 case. */ 1245 if (!je32_to_cpu(latest_node->isize)) 1246 latest_node->isize = latest_node->dsize; 1247 1248 if (f->inocache->state != INO_STATE_CHECKING) { 1249 /* Symlink's inode data is the target path. Read it and 1250 * keep in RAM to facilitate quick follow symlink 1251 * operation. */ 1252 uint32_t csize = je32_to_cpu(latest_node->csize); 1253 if (csize > JFFS2_MAX_NAME_LEN) 1254 return -ENAMETOOLONG; 1255 f->target = kmalloc(csize + 1, GFP_KERNEL); 1256 if (!f->target) { 1257 JFFS2_ERROR("can't allocate %u bytes of memory for the symlink target path cache\n", csize); 1258 return -ENOMEM; 1259 } 1260 1261 ret = jffs2_flash_read(c, ref_offset(rii.latest_ref) + sizeof(*latest_node), 1262 csize, &retlen, (char *)f->target); 1263 1264 if (ret || retlen != csize) { 1265 if (retlen != csize) 1266 ret = -EIO; 1267 kfree(f->target); 1268 f->target = NULL; 1269 return ret; 1270 } 1271 1272 f->target[csize] = '\0'; 1273 dbg_readinode("symlink's target '%s' cached\n", f->target); 1274 } 1275 1276 /* fall through... */ 1277 1278 case S_IFBLK: 1279 case S_IFCHR: 1280 /* Certain inode types should have only one data node, and it's 1281 kept as the metadata node */ 1282 if (f->metadata) { 1283 JFFS2_ERROR("Argh. Special inode #%u with mode 0%o had metadata node\n", 1284 f->inocache->ino, jemode_to_cpu(latest_node->mode)); 1285 return -EIO; 1286 } 1287 if (!frag_first(&f->fragtree)) { 1288 JFFS2_ERROR("Argh. Special inode #%u with mode 0%o has no fragments\n", 1289 f->inocache->ino, jemode_to_cpu(latest_node->mode)); 1290 return -EIO; 1291 } 1292 /* ASSERT: f->fraglist != NULL */ 1293 if (frag_next(frag_first(&f->fragtree))) { 1294 JFFS2_ERROR("Argh. Special inode #%u with mode 0x%x had more than one node\n", 1295 f->inocache->ino, jemode_to_cpu(latest_node->mode)); 1296 /* FIXME: Deal with it - check crc32, check for duplicate node, check times and discard the older one */ 1297 return -EIO; 1298 } 1299 /* OK. We're happy */ 1300 f->metadata = frag_first(&f->fragtree)->node; 1301 jffs2_free_node_frag(frag_first(&f->fragtree)); 1302 f->fragtree = RB_ROOT; 1303 break; 1304 } 1305 if (f->inocache->state == INO_STATE_READING) 1306 jffs2_set_inocache_state(c, f->inocache, INO_STATE_PRESENT); 1307 1308 return 0; 1309} 1310 1311/* Scan the list of all nodes present for this ino, build map of versions, etc. */ 1312int jffs2_do_read_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, 1313 uint32_t ino, struct jffs2_raw_inode *latest_node) 1314{ 1315 dbg_readinode("read inode #%u\n", ino); 1316 1317 retry_inocache: 1318 spin_lock(&c->inocache_lock); 1319 f->inocache = jffs2_get_ino_cache(c, ino); 1320 1321 if (f->inocache) { 1322 /* Check its state. We may need to wait before we can use it */ 1323 switch(f->inocache->state) { 1324 case INO_STATE_UNCHECKED: 1325 case INO_STATE_CHECKEDABSENT: 1326 f->inocache->state = INO_STATE_READING; 1327 break; 1328 1329 case INO_STATE_CHECKING: 1330 case INO_STATE_GC: 1331 /* If it's in either of these states, we need 1332 to wait for whoever's got it to finish and 1333 put it back. */ 1334 dbg_readinode("waiting for ino #%u in state %d\n", ino, f->inocache->state); 1335 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock); 1336 goto retry_inocache; 1337 1338 case INO_STATE_READING: 1339 case INO_STATE_PRESENT: 1340 /* Eep. This should never happen. It can 1341 happen if Linux calls read_inode() again 1342 before clear_inode() has finished though. */ 1343 JFFS2_ERROR("Eep. Trying to read_inode #%u when it's already in state %d!\n", ino, f->inocache->state); 1344 /* Fail. That's probably better than allowing it to succeed */ 1345 f->inocache = NULL; 1346 break; 1347 1348 default: 1349 BUG(); 1350 } 1351 } 1352 spin_unlock(&c->inocache_lock); 1353 1354 if (!f->inocache && ino == 1) { 1355 /* Special case - no root inode on medium */ 1356 f->inocache = jffs2_alloc_inode_cache(); 1357 if (!f->inocache) { 1358 JFFS2_ERROR("cannot allocate inocache for root inode\n"); 1359 return -ENOMEM; 1360 } 1361 dbg_readinode("creating inocache for root inode\n"); 1362 memset(f->inocache, 0, sizeof(struct jffs2_inode_cache)); 1363 f->inocache->ino = f->inocache->pino_nlink = 1; 1364 f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache; 1365 f->inocache->state = INO_STATE_READING; 1366 jffs2_add_ino_cache(c, f->inocache); 1367 } 1368 if (!f->inocache) { 1369 JFFS2_ERROR("requestied to read an nonexistent ino %u\n", ino); 1370 return -ENOENT; 1371 } 1372 1373 return jffs2_do_read_inode_internal(c, f, latest_node); 1374} 1375 1376int jffs2_do_crccheck_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic) 1377{ 1378 struct jffs2_raw_inode n; 1379 struct jffs2_inode_info *f = kzalloc(sizeof(*f), GFP_KERNEL); 1380 int ret; 1381 1382 if (!f) 1383 return -ENOMEM; 1384 1385 mutex_init(&f->sem); 1386 mutex_lock(&f->sem); 1387 f->inocache = ic; 1388 1389 ret = jffs2_do_read_inode_internal(c, f, &n); 1390 mutex_unlock(&f->sem); 1391 jffs2_do_clear_inode(c, f); 1392 jffs2_xattr_do_crccheck_inode(c, ic); 1393 kfree (f); 1394 return ret; 1395} 1396 1397void jffs2_do_clear_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f) 1398{ 1399 struct jffs2_full_dirent *fd, *fds; 1400 int deleted; 1401 1402 jffs2_xattr_delete_inode(c, f->inocache); 1403 mutex_lock(&f->sem); 1404 deleted = f->inocache && !f->inocache->pino_nlink; 1405 1406 if (f->inocache && f->inocache->state != INO_STATE_CHECKING) 1407 jffs2_set_inocache_state(c, f->inocache, INO_STATE_CLEARING); 1408 1409 if (f->metadata) { 1410 if (deleted) 1411 jffs2_mark_node_obsolete(c, f->metadata->raw); 1412 jffs2_free_full_dnode(f->metadata); 1413 } 1414 1415 jffs2_kill_fragtree(&f->fragtree, deleted?c:NULL); 1416 1417 if (f->target) { 1418 kfree(f->target); 1419 f->target = NULL; 1420 } 1421 1422 fds = f->dents; 1423 while(fds) { 1424 fd = fds; 1425 fds = fd->next; 1426 jffs2_free_full_dirent(fd); 1427 } 1428 1429 if (f->inocache && f->inocache->state != INO_STATE_CHECKING) { 1430 jffs2_set_inocache_state(c, f->inocache, INO_STATE_CHECKEDABSENT); 1431 if (f->inocache->nodes == (void *)f->inocache) 1432 jffs2_del_ino_cache(c, f->inocache); 1433 } 1434 1435 mutex_unlock(&f->sem); 1436} 1437