1 /* 2 * JFFS2 -- Journalling Flash File System, Version 2. 3 * 4 * Copyright (C) 2001-2003 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 * $Id: nodelist.c,v 1.115 2005/11/07 11:14:40 gleixner Exp $ 11 * 12 */ 13 14 #include <linux/kernel.h> 15 #include <linux/sched.h> 16 #include <linux/fs.h> 17 #include <linux/mtd/mtd.h> 18 #include <linux/rbtree.h> 19 #include <linux/crc32.h> 20 #include <linux/slab.h> 21 #include <linux/pagemap.h> 22 #include "nodelist.h" 23 24 void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list) 25 { 26 struct jffs2_full_dirent **prev = list; 27 28 dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino); 29 30 while ((*prev) && (*prev)->nhash <= new->nhash) { 31 if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) { 32 /* Duplicate. Free one */ 33 if (new->version < (*prev)->version) { 34 dbg_dentlist("Eep! Marking new dirent node is obsolete, old is \"%s\", ino #%u\n", 35 (*prev)->name, (*prev)->ino); 36 jffs2_mark_node_obsolete(c, new->raw); 37 jffs2_free_full_dirent(new); 38 } else { 39 dbg_dentlist("marking old dirent \"%s\", ino #%u bsolete\n", 40 (*prev)->name, (*prev)->ino); 41 new->next = (*prev)->next; 42 jffs2_mark_node_obsolete(c, ((*prev)->raw)); 43 jffs2_free_full_dirent(*prev); 44 *prev = new; 45 } 46 return; 47 } 48 prev = &((*prev)->next); 49 } 50 new->next = *prev; 51 *prev = new; 52 } 53 54 void jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size) 55 { 56 struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size); 57 58 dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size); 59 60 /* We know frag->ofs <= size. That's what lookup does for us */ 61 if (frag && frag->ofs != size) { 62 if (frag->ofs+frag->size > size) { 63 frag->size = size - frag->ofs; 64 } 65 frag = frag_next(frag); 66 } 67 while (frag && frag->ofs >= size) { 68 struct jffs2_node_frag *next = frag_next(frag); 69 70 frag_erase(frag, list); 71 jffs2_obsolete_node_frag(c, frag); 72 frag = next; 73 } 74 75 if (size == 0) 76 return; 77 78 /* 79 * If the last fragment starts at the RAM page boundary, it is 80 * REF_PRISTINE irrespective of its size. 81 */ 82 frag = frag_last(list); 83 if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) { 84 dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n", 85 frag->ofs, frag->ofs + frag->size); 86 frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE; 87 } 88 } 89 90 void jffs2_obsolete_node_frag(struct jffs2_sb_info *c, struct jffs2_node_frag *this) 91 { 92 if (this->node) { 93 this->node->frags--; 94 if (!this->node->frags) { 95 /* The node has no valid frags left. It's totally obsoleted */ 96 dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n", 97 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size); 98 jffs2_mark_node_obsolete(c, this->node->raw); 99 jffs2_free_full_dnode(this->node); 100 } else { 101 dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n", 102 ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags); 103 mark_ref_normal(this->node->raw); 104 } 105 106 } 107 jffs2_free_node_frag(this); 108 } 109 110 static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base) 111 { 112 struct rb_node *parent = &base->rb; 113 struct rb_node **link = &parent; 114 115 dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size); 116 117 while (*link) { 118 parent = *link; 119 base = rb_entry(parent, struct jffs2_node_frag, rb); 120 121 if (newfrag->ofs > base->ofs) 122 link = &base->rb.rb_right; 123 else if (newfrag->ofs < base->ofs) 124 link = &base->rb.rb_left; 125 else { 126 JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base); 127 BUG(); 128 } 129 } 130 131 rb_link_node(&newfrag->rb, &base->rb, link); 132 } 133 134 /* 135 * Allocate and initializes a new fragment. 136 */ 137 static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size) 138 { 139 struct jffs2_node_frag *newfrag; 140 141 newfrag = jffs2_alloc_node_frag(); 142 if (likely(newfrag)) { 143 newfrag->ofs = ofs; 144 newfrag->size = size; 145 newfrag->node = fn; 146 } else { 147 JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n"); 148 } 149 150 return newfrag; 151 } 152 153 /* 154 * Called when there is no overlapping fragment exist. Inserts a hole before the new 155 * fragment and inserts the new fragment to the fragtree. 156 */ 157 static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root, 158 struct jffs2_node_frag *newfrag, 159 struct jffs2_node_frag *this, uint32_t lastend) 160 { 161 if (lastend < newfrag->node->ofs) { 162 /* put a hole in before the new fragment */ 163 struct jffs2_node_frag *holefrag; 164 165 holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend); 166 if (unlikely(!holefrag)) { 167 jffs2_free_node_frag(newfrag); 168 return -ENOMEM; 169 } 170 171 if (this) { 172 /* By definition, the 'this' node has no right-hand child, 173 because there are no frags with offset greater than it. 174 So that's where we want to put the hole */ 175 dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n", 176 holefrag->ofs, holefrag->ofs + holefrag->size); 177 rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right); 178 } else { 179 dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n", 180 holefrag->ofs, holefrag->ofs + holefrag->size); 181 rb_link_node(&holefrag->rb, NULL, &root->rb_node); 182 } 183 rb_insert_color(&holefrag->rb, root); 184 this = holefrag; 185 } 186 187 if (this) { 188 /* By definition, the 'this' node has no right-hand child, 189 because there are no frags with offset greater than it. 190 So that's where we want to put new fragment */ 191 dbg_fragtree2("add the new node at the right\n"); 192 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right); 193 } else { 194 dbg_fragtree2("insert the new node at the root of the tree\n"); 195 rb_link_node(&newfrag->rb, NULL, &root->rb_node); 196 } 197 rb_insert_color(&newfrag->rb, root); 198 199 return 0; 200 } 201 202 /* Doesn't set inode->i_size */ 203 static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag) 204 { 205 struct jffs2_node_frag *this; 206 uint32_t lastend; 207 208 /* Skip all the nodes which are completed before this one starts */ 209 this = jffs2_lookup_node_frag(root, newfrag->node->ofs); 210 211 if (this) { 212 dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n", 213 this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this); 214 lastend = this->ofs + this->size; 215 } else { 216 dbg_fragtree2("lookup gave no frag\n"); 217 lastend = 0; 218 } 219 220 /* See if we ran off the end of the fragtree */ 221 if (lastend <= newfrag->ofs) { 222 /* We did */ 223 224 /* Check if 'this' node was on the same page as the new node. 225 If so, both 'this' and the new node get marked REF_NORMAL so 226 the GC can take a look. 227 */ 228 if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) { 229 if (this->node) 230 mark_ref_normal(this->node->raw); 231 mark_ref_normal(newfrag->node->raw); 232 } 233 234 return no_overlapping_node(c, root, newfrag, this, lastend); 235 } 236 237 if (this->node) 238 dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n", 239 this->ofs, this->ofs + this->size, 240 ref_offset(this->node->raw), ref_flags(this->node->raw)); 241 else 242 dbg_fragtree2("dealing with hole frag %u-%u.\n", 243 this->ofs, this->ofs + this->size); 244 245 /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes, 246 * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs 247 */ 248 if (newfrag->ofs > this->ofs) { 249 /* This node isn't completely obsoleted. The start of it remains valid */ 250 251 /* Mark the new node and the partially covered node REF_NORMAL -- let 252 the GC take a look at them */ 253 mark_ref_normal(newfrag->node->raw); 254 if (this->node) 255 mark_ref_normal(this->node->raw); 256 257 if (this->ofs + this->size > newfrag->ofs + newfrag->size) { 258 /* The new node splits 'this' frag into two */ 259 struct jffs2_node_frag *newfrag2; 260 261 if (this->node) 262 dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n", 263 this->ofs, this->ofs+this->size, ref_offset(this->node->raw)); 264 else 265 dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n", 266 this->ofs, this->ofs+this->size); 267 268 /* New second frag pointing to this's node */ 269 newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size, 270 this->ofs + this->size - newfrag->ofs - newfrag->size); 271 if (unlikely(!newfrag2)) 272 return -ENOMEM; 273 if (this->node) 274 this->node->frags++; 275 276 /* Adjust size of original 'this' */ 277 this->size = newfrag->ofs - this->ofs; 278 279 /* Now, we know there's no node with offset 280 greater than this->ofs but smaller than 281 newfrag2->ofs or newfrag->ofs, for obvious 282 reasons. So we can do a tree insert from 283 'this' to insert newfrag, and a tree insert 284 from newfrag to insert newfrag2. */ 285 jffs2_fragtree_insert(newfrag, this); 286 rb_insert_color(&newfrag->rb, root); 287 288 jffs2_fragtree_insert(newfrag2, newfrag); 289 rb_insert_color(&newfrag2->rb, root); 290 291 return 0; 292 } 293 /* New node just reduces 'this' frag in size, doesn't split it */ 294 this->size = newfrag->ofs - this->ofs; 295 296 /* Again, we know it lives down here in the tree */ 297 jffs2_fragtree_insert(newfrag, this); 298 rb_insert_color(&newfrag->rb, root); 299 } else { 300 /* New frag starts at the same point as 'this' used to. Replace 301 it in the tree without doing a delete and insertion */ 302 dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n", 303 newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size); 304 305 rb_replace_node(&this->rb, &newfrag->rb, root); 306 307 if (newfrag->ofs + newfrag->size >= this->ofs+this->size) { 308 dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size); 309 jffs2_obsolete_node_frag(c, this); 310 } else { 311 this->ofs += newfrag->size; 312 this->size -= newfrag->size; 313 314 jffs2_fragtree_insert(this, newfrag); 315 rb_insert_color(&this->rb, root); 316 return 0; 317 } 318 } 319 /* OK, now we have newfrag added in the correct place in the tree, but 320 frag_next(newfrag) may be a fragment which is overlapped by it 321 */ 322 while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) { 323 /* 'this' frag is obsoleted completely. */ 324 dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n", 325 this, this->ofs, this->ofs+this->size); 326 rb_erase(&this->rb, root); 327 jffs2_obsolete_node_frag(c, this); 328 } 329 /* Now we're pointing at the first frag which isn't totally obsoleted by 330 the new frag */ 331 332 if (!this || newfrag->ofs + newfrag->size == this->ofs) 333 return 0; 334 335 /* Still some overlap but we don't need to move it in the tree */ 336 this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size); 337 this->ofs = newfrag->ofs + newfrag->size; 338 339 /* And mark them REF_NORMAL so the GC takes a look at them */ 340 if (this->node) 341 mark_ref_normal(this->node->raw); 342 mark_ref_normal(newfrag->node->raw); 343 344 return 0; 345 } 346 347 /* 348 * Given an inode, probably with existing tree of fragments, add the new node 349 * to the fragment tree. 350 */ 351 int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn) 352 { 353 int ret; 354 struct jffs2_node_frag *newfrag; 355 356 if (unlikely(!fn->size)) 357 return 0; 358 359 newfrag = new_fragment(fn, fn->ofs, fn->size); 360 if (unlikely(!newfrag)) 361 return -ENOMEM; 362 newfrag->node->frags = 1; 363 364 dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n", 365 fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag); 366 367 ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag); 368 if (unlikely(ret)) 369 return ret; 370 371 /* If we now share a page with other nodes, mark either previous 372 or next node REF_NORMAL, as appropriate. */ 373 if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) { 374 struct jffs2_node_frag *prev = frag_prev(newfrag); 375 376 mark_ref_normal(fn->raw); 377 /* If we don't start at zero there's _always_ a previous */ 378 if (prev->node) 379 mark_ref_normal(prev->node->raw); 380 } 381 382 if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) { 383 struct jffs2_node_frag *next = frag_next(newfrag); 384 385 if (next) { 386 mark_ref_normal(fn->raw); 387 if (next->node) 388 mark_ref_normal(next->node->raw); 389 } 390 } 391 jffs2_dbg_fragtree_paranoia_check_nolock(f); 392 393 return 0; 394 } 395 396 /* 397 * Check the data CRC of the node. 398 * 399 * Returns: 0 if the data CRC is correct; 400 * 1 - if incorrect; 401 * error code if an error occured. 402 */ 403 static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn) 404 { 405 struct jffs2_raw_node_ref *ref = tn->fn->raw; 406 int err = 0, pointed = 0; 407 struct jffs2_eraseblock *jeb; 408 unsigned char *buffer; 409 uint32_t crc, ofs, len; 410 size_t retlen; 411 412 BUG_ON(tn->csize == 0); 413 414 if (!jffs2_is_writebuffered(c)) 415 goto adj_acc; 416 417 /* Calculate how many bytes were already checked */ 418 ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode); 419 len = ofs % c->wbuf_pagesize; 420 if (likely(len)) 421 len = c->wbuf_pagesize - len; 422 423 if (len >= tn->csize) { 424 dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n", 425 ref_offset(ref), tn->csize, ofs); 426 goto adj_acc; 427 } 428 429 ofs += len; 430 len = tn->csize - len; 431 432 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", 433 ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len); 434 435 #ifndef __ECOS 436 /* TODO: instead, incapsulate point() stuff to jffs2_flash_read(), 437 * adding and jffs2_flash_read_end() interface. */ 438 if (c->mtd->point) { 439 err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer); 440 if (!err && retlen < tn->csize) { 441 JFFS2_WARNING("MTD point returned len too short: %zu " 442 "instead of %u.\n", retlen, tn->csize); 443 c->mtd->unpoint(c->mtd, buffer, ofs, len); 444 } else if (err) 445 JFFS2_WARNING("MTD point failed: error code %d.\n", err); 446 else 447 pointed = 1; /* succefully pointed to device */ 448 } 449 #endif 450 451 if (!pointed) { 452 buffer = kmalloc(len, GFP_KERNEL); 453 if (unlikely(!buffer)) 454 return -ENOMEM; 455 456 /* TODO: this is very frequent pattern, make it a separate 457 * routine */ 458 err = jffs2_flash_read(c, ofs, len, &retlen, buffer); 459 if (err) { 460 JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err); 461 goto free_out; 462 } 463 464 if (retlen != len) { 465 JFFS2_ERROR("short read at %#08x: %zd instead of %d.\n", 466 ofs, retlen, len); 467 err = -EIO; 468 goto free_out; 469 } 470 } 471 472 /* Continue calculating CRC */ 473 crc = crc32(tn->partial_crc, buffer, len); 474 if(!pointed) 475 kfree(buffer); 476 #ifndef __ECOS 477 else 478 c->mtd->unpoint(c->mtd, buffer, ofs, len); 479 #endif 480 481 if (crc != tn->data_crc) { 482 JFFS2_NOTICE("wrong data CRC in data node at 0x%08x: read %#08x, calculated %#08x.\n", 483 ofs, tn->data_crc, crc); 484 return 1; 485 } 486 487 adj_acc: 488 jeb = &c->blocks[ref->flash_offset / c->sector_size]; 489 len = ref_totlen(c, jeb, ref); 490 491 /* 492 * Mark the node as having been checked and fix the 493 * accounting accordingly. 494 */ 495 spin_lock(&c->erase_completion_lock); 496 jeb->used_size += len; 497 jeb->unchecked_size -= len; 498 c->used_size += len; 499 c->unchecked_size -= len; 500 spin_unlock(&c->erase_completion_lock); 501 502 return 0; 503 504 free_out: 505 if(!pointed) 506 kfree(buffer); 507 #ifndef __ECOS 508 else 509 c->mtd->unpoint(c->mtd, buffer, ofs, len); 510 #endif 511 return err; 512 } 513 514 /* 515 * Helper function for jffs2_add_older_frag_to_fragtree(). 516 * 517 * Checks the node if we are in the checking stage. 518 */ 519 static int check_node(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_tmp_dnode_info *tn) 520 { 521 int ret; 522 523 BUG_ON(ref_obsolete(tn->fn->raw)); 524 525 /* We only check the data CRC of unchecked nodes */ 526 if (ref_flags(tn->fn->raw) != REF_UNCHECKED) 527 return 0; 528 529 dbg_fragtree2("check node %#04x-%#04x, phys offs %#08x.\n", 530 tn->fn->ofs, tn->fn->ofs + tn->fn->size, ref_offset(tn->fn->raw)); 531 532 ret = check_node_data(c, tn); 533 if (unlikely(ret < 0)) { 534 JFFS2_ERROR("check_node_data() returned error: %d.\n", 535 ret); 536 } else if (unlikely(ret > 0)) { 537 dbg_fragtree2("CRC error, mark it obsolete.\n"); 538 jffs2_mark_node_obsolete(c, tn->fn->raw); 539 } 540 541 return ret; 542 } 543 544 /* 545 * Helper function for jffs2_add_older_frag_to_fragtree(). 546 * 547 * Called when the new fragment that is being inserted 548 * splits a hole fragment. 549 */ 550 static int split_hole(struct jffs2_sb_info *c, struct rb_root *root, 551 struct jffs2_node_frag *newfrag, struct jffs2_node_frag *hole) 552 { 553 dbg_fragtree2("fragment %#04x-%#04x splits the hole %#04x-%#04x\n", 554 newfrag->ofs, newfrag->ofs + newfrag->size, hole->ofs, hole->ofs + hole->size); 555 556 if (hole->ofs == newfrag->ofs) { 557 /* 558 * Well, the new fragment actually starts at the same offset as 559 * the hole. 560 */ 561 if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) { 562 /* 563 * We replace the overlapped left part of the hole by 564 * the new node. 565 */ 566 567 dbg_fragtree2("insert fragment %#04x-%#04x and cut the left part of the hole\n", 568 newfrag->ofs, newfrag->ofs + newfrag->size); 569 rb_replace_node(&hole->rb, &newfrag->rb, root); 570 571 hole->ofs += newfrag->size; 572 hole->size -= newfrag->size; 573 574 /* 575 * We know that 'hole' should be the right hand 576 * fragment. 577 */ 578 jffs2_fragtree_insert(hole, newfrag); 579 rb_insert_color(&hole->rb, root); 580 } else { 581 /* 582 * Ah, the new fragment is of the same size as the hole. 583 * Relace the hole by it. 584 */ 585 dbg_fragtree2("insert fragment %#04x-%#04x and overwrite hole\n", 586 newfrag->ofs, newfrag->ofs + newfrag->size); 587 rb_replace_node(&hole->rb, &newfrag->rb, root); 588 jffs2_free_node_frag(hole); 589 } 590 } else { 591 /* The new fragment lefts some hole space at the left */ 592 593 struct jffs2_node_frag * newfrag2 = NULL; 594 595 if (hole->ofs + hole->size > newfrag->ofs + newfrag->size) { 596 /* The new frag also lefts some space at the right */ 597 newfrag2 = new_fragment(NULL, newfrag->ofs + 598 newfrag->size, hole->ofs + hole->size 599 - newfrag->ofs - newfrag->size); 600 if (unlikely(!newfrag2)) { 601 jffs2_free_node_frag(newfrag); 602 return -ENOMEM; 603 } 604 } 605 606 hole->size = newfrag->ofs - hole->ofs; 607 dbg_fragtree2("left the hole %#04x-%#04x at the left and inserd fragment %#04x-%#04x\n", 608 hole->ofs, hole->ofs + hole->size, newfrag->ofs, newfrag->ofs + newfrag->size); 609 610 jffs2_fragtree_insert(newfrag, hole); 611 rb_insert_color(&newfrag->rb, root); 612 613 if (newfrag2) { 614 dbg_fragtree2("left the hole %#04x-%#04x at the right\n", 615 newfrag2->ofs, newfrag2->ofs + newfrag2->size); 616 jffs2_fragtree_insert(newfrag2, newfrag); 617 rb_insert_color(&newfrag2->rb, root); 618 } 619 } 620 621 return 0; 622 } 623 624 /* 625 * This function is used when we build inode. It expects the nodes are passed 626 * in the decreasing version order. The whole point of this is to improve the 627 * inodes checking on NAND: we check the nodes' data CRC only when they are not 628 * obsoleted. Previously, add_frag_to_fragtree() function was used and 629 * nodes were passed to it in the increasing version ordes and CRCs of all 630 * nodes were checked. 631 * 632 * Note: tn->fn->size shouldn't be zero. 633 * 634 * Returns 0 if the node was inserted 635 * 1 if it wasn't inserted (since it is obsolete) 636 * < 0 an if error occured 637 */ 638 int jffs2_add_older_frag_to_fragtree(struct jffs2_sb_info *c, struct jffs2_inode_info *f, 639 struct jffs2_tmp_dnode_info *tn) 640 { 641 struct jffs2_node_frag *this, *newfrag; 642 uint32_t lastend; 643 struct jffs2_full_dnode *fn = tn->fn; 644 struct rb_root *root = &f->fragtree; 645 uint32_t fn_size = fn->size, fn_ofs = fn->ofs; 646 int err, checked = 0; 647 int ref_flag; 648 649 dbg_fragtree("insert fragment %#04x-%#04x, ver %u\n", fn_ofs, fn_ofs + fn_size, tn->version); 650 651 /* Skip all the nodes which are completed before this one starts */ 652 this = jffs2_lookup_node_frag(root, fn_ofs); 653 if (this) 654 dbg_fragtree2("'this' found %#04x-%#04x (%s)\n", this->ofs, this->ofs + this->size, this->node ? "data" : "hole"); 655 656 if (this) 657 lastend = this->ofs + this->size; 658 else 659 lastend = 0; 660 661 /* Detect the preliminary type of node */ 662 if (fn->size >= PAGE_CACHE_SIZE) 663 ref_flag = REF_PRISTINE; 664 else 665 ref_flag = REF_NORMAL; 666 667 /* See if we ran off the end of the root */ 668 if (lastend <= fn_ofs) { 669 /* We did */ 670 671 /* 672 * We are going to insert the new node into the 673 * fragment tree, so check it. 674 */ 675 err = check_node(c, f, tn); 676 if (err != 0) 677 return err; 678 679 fn->frags = 1; 680 681 newfrag = new_fragment(fn, fn_ofs, fn_size); 682 if (unlikely(!newfrag)) 683 return -ENOMEM; 684 685 err = no_overlapping_node(c, root, newfrag, this, lastend); 686 if (unlikely(err != 0)) { 687 jffs2_free_node_frag(newfrag); 688 return err; 689 } 690 691 goto out_ok; 692 } 693 694 fn->frags = 0; 695 696 while (1) { 697 /* 698 * Here we have: 699 * fn_ofs < this->ofs + this->size && fn_ofs >= this->ofs. 700 * 701 * Remember, 'this' has higher version, any non-hole node 702 * which is already in the fragtree is newer then the newly 703 * inserted. 704 */ 705 if (!this->node) { 706 /* 707 * 'this' is the hole fragment, so at least the 708 * beginning of the new fragment is valid. 709 */ 710 711 /* 712 * We are going to insert the new node into the 713 * fragment tree, so check it. 714 */ 715 if (!checked) { 716 err = check_node(c, f, tn); 717 if (unlikely(err != 0)) 718 return err; 719 checked = 1; 720 } 721 722 if (this->ofs + this->size >= fn_ofs + fn_size) { 723 /* We split the hole on two parts */ 724 725 fn->frags += 1; 726 newfrag = new_fragment(fn, fn_ofs, fn_size); 727 if (unlikely(!newfrag)) 728 return -ENOMEM; 729 730 err = split_hole(c, root, newfrag, this); 731 if (unlikely(err)) 732 return err; 733 goto out_ok; 734 } 735 736 /* 737 * The beginning of the new fragment is valid since it 738 * overlaps the hole node. 739 */ 740 741 ref_flag = REF_NORMAL; 742 743 fn->frags += 1; 744 newfrag = new_fragment(fn, fn_ofs, 745 this->ofs + this->size - fn_ofs); 746 if (unlikely(!newfrag)) 747 return -ENOMEM; 748 749 if (fn_ofs == this->ofs) { 750 /* 751 * The new node starts at the same offset as 752 * the hole and supersieds the hole. 753 */ 754 dbg_fragtree2("add the new fragment instead of hole %#04x-%#04x, refcnt %d\n", 755 fn_ofs, fn_ofs + this->ofs + this->size - fn_ofs, fn->frags); 756 757 rb_replace_node(&this->rb, &newfrag->rb, root); 758 jffs2_free_node_frag(this); 759 } else { 760 /* 761 * The hole becomes shorter as its right part 762 * is supersieded by the new fragment. 763 */ 764 dbg_fragtree2("reduce size of hole %#04x-%#04x to %#04x-%#04x\n", 765 this->ofs, this->ofs + this->size, this->ofs, this->ofs + this->size - newfrag->size); 766 767 dbg_fragtree2("add new fragment %#04x-%#04x, refcnt %d\n", fn_ofs, 768 fn_ofs + this->ofs + this->size - fn_ofs, fn->frags); 769 770 this->size -= newfrag->size; 771 jffs2_fragtree_insert(newfrag, this); 772 rb_insert_color(&newfrag->rb, root); 773 } 774 775 fn_ofs += newfrag->size; 776 fn_size -= newfrag->size; 777 this = rb_entry(rb_next(&newfrag->rb), 778 struct jffs2_node_frag, rb); 779 780 dbg_fragtree2("switch to the next 'this' fragment: %#04x-%#04x %s\n", 781 this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)"); 782 } 783 784 /* 785 * 'This' node is not the hole so it obsoletes the new fragment 786 * either fully or partially. 787 */ 788 if (this->ofs + this->size >= fn_ofs + fn_size) { 789 /* The new node is obsolete, drop it */ 790 if (fn->frags == 0) { 791 dbg_fragtree2("%#04x-%#04x is obsolete, mark it obsolete\n", fn_ofs, fn_ofs + fn_size); 792 ref_flag = REF_OBSOLETE; 793 } 794 goto out_ok; 795 } else { 796 struct jffs2_node_frag *new_this; 797 798 /* 'This' node obsoletes the beginning of the new node */ 799 dbg_fragtree2("the beginning %#04x-%#04x is obsolete\n", fn_ofs, this->ofs + this->size); 800 801 ref_flag = REF_NORMAL; 802 803 fn_size -= this->ofs + this->size - fn_ofs; 804 fn_ofs = this->ofs + this->size; 805 dbg_fragtree2("now considering %#04x-%#04x\n", fn_ofs, fn_ofs + fn_size); 806 807 new_this = rb_entry(rb_next(&this->rb), struct jffs2_node_frag, rb); 808 if (!new_this) { 809 /* 810 * There is no next fragment. Add the rest of 811 * the new node as the right-hand child. 812 */ 813 if (!checked) { 814 err = check_node(c, f, tn); 815 if (unlikely(err != 0)) 816 return err; 817 checked = 1; 818 } 819 820 fn->frags += 1; 821 newfrag = new_fragment(fn, fn_ofs, fn_size); 822 if (unlikely(!newfrag)) 823 return -ENOMEM; 824 825 dbg_fragtree2("there are no more fragments, insert %#04x-%#04x\n", 826 newfrag->ofs, newfrag->ofs + newfrag->size); 827 rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right); 828 rb_insert_color(&newfrag->rb, root); 829 goto out_ok; 830 } else { 831 this = new_this; 832 dbg_fragtree2("switch to the next 'this' fragment: %#04x-%#04x %s\n", 833 this->ofs, this->ofs + this->size, this->node ? "(data)" : "(hole)"); 834 } 835 } 836 } 837 838 out_ok: 839 BUG_ON(fn->size < PAGE_CACHE_SIZE && ref_flag == REF_PRISTINE); 840 841 if (ref_flag == REF_OBSOLETE) { 842 dbg_fragtree2("the node is obsolete now\n"); 843 /* jffs2_mark_node_obsolete() will adjust space accounting */ 844 jffs2_mark_node_obsolete(c, fn->raw); 845 return 1; 846 } 847 848 dbg_fragtree2("the node is \"%s\" now\n", ref_flag == REF_NORMAL ? "REF_NORMAL" : "REF_PRISTINE"); 849 850 /* Space accounting was adjusted at check_node_data() */ 851 spin_lock(&c->erase_completion_lock); 852 fn->raw->flash_offset = ref_offset(fn->raw) | ref_flag; 853 spin_unlock(&c->erase_completion_lock); 854 855 return 0; 856 } 857 858 void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state) 859 { 860 spin_lock(&c->inocache_lock); 861 ic->state = state; 862 wake_up(&c->inocache_wq); 863 spin_unlock(&c->inocache_lock); 864 } 865 866 /* During mount, this needs no locking. During normal operation, its 867 callers want to do other stuff while still holding the inocache_lock. 868 Rather than introducing special case get_ino_cache functions or 869 callbacks, we just let the caller do the locking itself. */ 870 871 struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino) 872 { 873 struct jffs2_inode_cache *ret; 874 875 ret = c->inocache_list[ino % INOCACHE_HASHSIZE]; 876 while (ret && ret->ino < ino) { 877 ret = ret->next; 878 } 879 880 if (ret && ret->ino != ino) 881 ret = NULL; 882 883 return ret; 884 } 885 886 void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new) 887 { 888 struct jffs2_inode_cache **prev; 889 890 spin_lock(&c->inocache_lock); 891 if (!new->ino) 892 new->ino = ++c->highest_ino; 893 894 dbg_inocache("add %p (ino #%u)\n", new, new->ino); 895 896 prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE]; 897 898 while ((*prev) && (*prev)->ino < new->ino) { 899 prev = &(*prev)->next; 900 } 901 new->next = *prev; 902 *prev = new; 903 904 spin_unlock(&c->inocache_lock); 905 } 906 907 void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old) 908 { 909 struct jffs2_inode_cache **prev; 910 911 dbg_inocache("del %p (ino #%u)\n", old, old->ino); 912 spin_lock(&c->inocache_lock); 913 914 prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE]; 915 916 while ((*prev) && (*prev)->ino < old->ino) { 917 prev = &(*prev)->next; 918 } 919 if ((*prev) == old) { 920 *prev = old->next; 921 } 922 923 /* Free it now unless it's in READING or CLEARING state, which 924 are the transitions upon read_inode() and clear_inode(). The 925 rest of the time we know nobody else is looking at it, and 926 if it's held by read_inode() or clear_inode() they'll free it 927 for themselves. */ 928 if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING) 929 jffs2_free_inode_cache(old); 930 931 spin_unlock(&c->inocache_lock); 932 } 933 934 void jffs2_free_ino_caches(struct jffs2_sb_info *c) 935 { 936 int i; 937 struct jffs2_inode_cache *this, *next; 938 939 for (i=0; i<INOCACHE_HASHSIZE; i++) { 940 this = c->inocache_list[i]; 941 while (this) { 942 next = this->next; 943 jffs2_free_inode_cache(this); 944 this = next; 945 } 946 c->inocache_list[i] = NULL; 947 } 948 } 949 950 void jffs2_free_raw_node_refs(struct jffs2_sb_info *c) 951 { 952 int i; 953 struct jffs2_raw_node_ref *this, *next; 954 955 for (i=0; i<c->nr_blocks; i++) { 956 this = c->blocks[i].first_node; 957 while(this) { 958 next = this->next_phys; 959 jffs2_free_raw_node_ref(this); 960 this = next; 961 } 962 c->blocks[i].first_node = c->blocks[i].last_node = NULL; 963 } 964 } 965 966 struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset) 967 { 968 /* The common case in lookup is that there will be a node 969 which precisely matches. So we go looking for that first */ 970 struct rb_node *next; 971 struct jffs2_node_frag *prev = NULL; 972 struct jffs2_node_frag *frag = NULL; 973 974 dbg_fragtree2("root %p, offset %d\n", fragtree, offset); 975 976 next = fragtree->rb_node; 977 978 while(next) { 979 frag = rb_entry(next, struct jffs2_node_frag, rb); 980 981 if (frag->ofs + frag->size <= offset) { 982 /* Remember the closest smaller match on the way down */ 983 if (!prev || frag->ofs > prev->ofs) 984 prev = frag; 985 next = frag->rb.rb_right; 986 } else if (frag->ofs > offset) { 987 next = frag->rb.rb_left; 988 } else { 989 return frag; 990 } 991 } 992 993 /* Exact match not found. Go back up looking at each parent, 994 and return the closest smaller one */ 995 996 if (prev) 997 dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n", 998 prev->ofs, prev->ofs+prev->size); 999 else 1000 dbg_fragtree2("returning NULL, empty fragtree\n"); 1001 1002 return prev; 1003 } 1004 1005 /* Pass 'c' argument to indicate that nodes should be marked obsolete as 1006 they're killed. */ 1007 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c) 1008 { 1009 struct jffs2_node_frag *frag; 1010 struct jffs2_node_frag *parent; 1011 1012 if (!root->rb_node) 1013 return; 1014 1015 dbg_fragtree("killing\n"); 1016 1017 frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb)); 1018 while(frag) { 1019 if (frag->rb.rb_left) { 1020 frag = frag_left(frag); 1021 continue; 1022 } 1023 if (frag->rb.rb_right) { 1024 frag = frag_right(frag); 1025 continue; 1026 } 1027 1028 if (frag->node && !(--frag->node->frags)) { 1029 /* Not a hole, and it's the final remaining frag 1030 of this node. Free the node */ 1031 if (c) 1032 jffs2_mark_node_obsolete(c, frag->node->raw); 1033 1034 jffs2_free_full_dnode(frag->node); 1035 } 1036 parent = frag_parent(frag); 1037 if (parent) { 1038 if (frag_left(parent) == frag) 1039 parent->rb.rb_left = NULL; 1040 else 1041 parent->rb.rb_right = NULL; 1042 } 1043 1044 jffs2_free_node_frag(frag); 1045 frag = parent; 1046 1047 cond_resched(); 1048 } 1049 } 1050