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/mtd/mtd.h> 16 #include <linux/compiler.h> 17 #include <linux/sched.h> /* For cond_resched() */ 18 #include "nodelist.h" 19 #include "debug.h" 20 21 /* 22 * Check whether the user is allowed to write. 23 */ 24 static int jffs2_rp_can_write(struct jffs2_sb_info *c) 25 { 26 uint32_t avail; 27 struct jffs2_mount_opts *opts = &c->mount_opts; 28 29 avail = c->dirty_size + c->free_size + c->unchecked_size + 30 c->erasing_size - c->resv_blocks_write * c->sector_size 31 - c->nospc_dirty_size; 32 33 if (avail < 2 * opts->rp_size) 34 jffs2_dbg(1, "rpsize %u, dirty_size %u, free_size %u, " 35 "erasing_size %u, unchecked_size %u, " 36 "nr_erasing_blocks %u, avail %u, resrv %u\n", 37 opts->rp_size, c->dirty_size, c->free_size, 38 c->erasing_size, c->unchecked_size, 39 c->nr_erasing_blocks, avail, c->nospc_dirty_size); 40 41 if (avail > opts->rp_size) 42 return 1; 43 44 /* Always allow root */ 45 if (capable(CAP_SYS_RESOURCE)) 46 return 1; 47 48 jffs2_dbg(1, "forbid writing\n"); 49 return 0; 50 } 51 52 /** 53 * jffs2_reserve_space - request physical space to write nodes to flash 54 * @c: superblock info 55 * @minsize: Minimum acceptable size of allocation 56 * @len: Returned value of allocation length 57 * @prio: Allocation type - ALLOC_{NORMAL,DELETION} 58 * 59 * Requests a block of physical space on the flash. Returns zero for success 60 * and puts 'len' into the appropriate place, or returns -ENOSPC or other 61 * error if appropriate. Doesn't return len since that's 62 * 63 * If it returns zero, jffs2_reserve_space() also downs the per-filesystem 64 * allocation semaphore, to prevent more than one allocation from being 65 * active at any time. The semaphore is later released by jffs2_commit_allocation() 66 * 67 * jffs2_reserve_space() may trigger garbage collection in order to make room 68 * for the requested allocation. 69 */ 70 71 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 72 uint32_t *len, uint32_t sumsize); 73 74 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 75 uint32_t *len, int prio, uint32_t sumsize) 76 { 77 int ret = -EAGAIN; 78 int blocksneeded = c->resv_blocks_write; 79 /* align it */ 80 minsize = PAD(minsize); 81 82 jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize); 83 mutex_lock(&c->alloc_sem); 84 85 jffs2_dbg(1, "%s(): alloc sem got\n", __func__); 86 87 spin_lock(&c->erase_completion_lock); 88 89 /* 90 * Check if the free space is greater then size of the reserved pool. 91 * If not, only allow root to proceed with writing. 92 */ 93 if (prio != ALLOC_DELETION && !jffs2_rp_can_write(c)) { 94 ret = -ENOSPC; 95 goto out; 96 } 97 98 /* this needs a little more thought (true <tglx> :)) */ 99 while(ret == -EAGAIN) { 100 while(c->nr_free_blocks + c->nr_erasing_blocks < blocksneeded) { 101 uint32_t dirty, avail; 102 103 /* calculate real dirty size 104 * dirty_size contains blocks on erase_pending_list 105 * those blocks are counted in c->nr_erasing_blocks. 106 * If one block is actually erased, it is not longer counted as dirty_space 107 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it 108 * with c->nr_erasing_blocks * c->sector_size again. 109 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks 110 * This helps us to force gc and pick eventually a clean block to spread the load. 111 * We add unchecked_size here, as we hopefully will find some space to use. 112 * This will affect the sum only once, as gc first finishes checking 113 * of nodes. 114 */ 115 dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size + c->unchecked_size; 116 if (dirty < c->nospc_dirty_size) { 117 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) { 118 jffs2_dbg(1, "%s(): Low on dirty space to GC, but it's a deletion. Allowing...\n", 119 __func__); 120 break; 121 } 122 jffs2_dbg(1, "dirty size 0x%08x + unchecked_size 0x%08x < nospc_dirty_size 0x%08x, returning -ENOSPC\n", 123 dirty, c->unchecked_size, 124 c->sector_size); 125 126 spin_unlock(&c->erase_completion_lock); 127 mutex_unlock(&c->alloc_sem); 128 return -ENOSPC; 129 } 130 131 /* Calc possibly available space. Possibly available means that we 132 * don't know, if unchecked size contains obsoleted nodes, which could give us some 133 * more usable space. This will affect the sum only once, as gc first finishes checking 134 * of nodes. 135 + Return -ENOSPC, if the maximum possibly available space is less or equal than 136 * blocksneeded * sector_size. 137 * This blocks endless gc looping on a filesystem, which is nearly full, even if 138 * the check above passes. 139 */ 140 avail = c->free_size + c->dirty_size + c->erasing_size + c->unchecked_size; 141 if ( (avail / c->sector_size) <= blocksneeded) { 142 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) { 143 jffs2_dbg(1, "%s(): Low on possibly available space, but it's a deletion. Allowing...\n", 144 __func__); 145 break; 146 } 147 148 jffs2_dbg(1, "max. available size 0x%08x < blocksneeded * sector_size 0x%08x, returning -ENOSPC\n", 149 avail, blocksneeded * c->sector_size); 150 spin_unlock(&c->erase_completion_lock); 151 mutex_unlock(&c->alloc_sem); 152 return -ENOSPC; 153 } 154 155 mutex_unlock(&c->alloc_sem); 156 157 jffs2_dbg(1, "Triggering GC pass. nr_free_blocks %d, nr_erasing_blocks %d, free_size 0x%08x, dirty_size 0x%08x, wasted_size 0x%08x, used_size 0x%08x, erasing_size 0x%08x, bad_size 0x%08x (total 0x%08x of 0x%08x)\n", 158 c->nr_free_blocks, c->nr_erasing_blocks, 159 c->free_size, c->dirty_size, c->wasted_size, 160 c->used_size, c->erasing_size, c->bad_size, 161 c->free_size + c->dirty_size + 162 c->wasted_size + c->used_size + 163 c->erasing_size + c->bad_size, 164 c->flash_size); 165 spin_unlock(&c->erase_completion_lock); 166 167 ret = jffs2_garbage_collect_pass(c); 168 169 if (ret == -EAGAIN) { 170 spin_lock(&c->erase_completion_lock); 171 if (c->nr_erasing_blocks && 172 list_empty(&c->erase_pending_list) && 173 list_empty(&c->erase_complete_list)) { 174 DECLARE_WAITQUEUE(wait, current); 175 set_current_state(TASK_UNINTERRUPTIBLE); 176 add_wait_queue(&c->erase_wait, &wait); 177 jffs2_dbg(1, "%s waiting for erase to complete\n", 178 __func__); 179 spin_unlock(&c->erase_completion_lock); 180 181 schedule(); 182 remove_wait_queue(&c->erase_wait, &wait); 183 } else 184 spin_unlock(&c->erase_completion_lock); 185 } else if (ret) 186 return ret; 187 188 cond_resched(); 189 190 if (signal_pending(current)) 191 return -EINTR; 192 193 mutex_lock(&c->alloc_sem); 194 spin_lock(&c->erase_completion_lock); 195 } 196 197 ret = jffs2_do_reserve_space(c, minsize, len, sumsize); 198 if (ret) { 199 jffs2_dbg(1, "%s(): ret is %d\n", __func__, ret); 200 } 201 } 202 203 out: 204 spin_unlock(&c->erase_completion_lock); 205 if (!ret) 206 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1); 207 if (ret) 208 mutex_unlock(&c->alloc_sem); 209 return ret; 210 } 211 212 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, 213 uint32_t *len, uint32_t sumsize) 214 { 215 int ret = -EAGAIN; 216 minsize = PAD(minsize); 217 218 jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize); 219 220 spin_lock(&c->erase_completion_lock); 221 while(ret == -EAGAIN) { 222 ret = jffs2_do_reserve_space(c, minsize, len, sumsize); 223 if (ret) { 224 jffs2_dbg(1, "%s(): looping, ret is %d\n", 225 __func__, ret); 226 } 227 } 228 spin_unlock(&c->erase_completion_lock); 229 if (!ret) 230 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1); 231 232 return ret; 233 } 234 235 236 /* Classify nextblock (clean, dirty of verydirty) and force to select an other one */ 237 238 static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) 239 { 240 241 if (c->nextblock == NULL) { 242 jffs2_dbg(1, "%s(): Erase block at 0x%08x has already been placed in a list\n", 243 __func__, jeb->offset); 244 return; 245 } 246 /* Check, if we have a dirty block now, or if it was dirty already */ 247 if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) { 248 c->dirty_size += jeb->wasted_size; 249 c->wasted_size -= jeb->wasted_size; 250 jeb->dirty_size += jeb->wasted_size; 251 jeb->wasted_size = 0; 252 if (VERYDIRTY(c, jeb->dirty_size)) { 253 jffs2_dbg(1, "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 254 jeb->offset, jeb->free_size, jeb->dirty_size, 255 jeb->used_size); 256 list_add_tail(&jeb->list, &c->very_dirty_list); 257 } else { 258 jffs2_dbg(1, "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 259 jeb->offset, jeb->free_size, jeb->dirty_size, 260 jeb->used_size); 261 list_add_tail(&jeb->list, &c->dirty_list); 262 } 263 } else { 264 jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 265 jeb->offset, jeb->free_size, jeb->dirty_size, 266 jeb->used_size); 267 list_add_tail(&jeb->list, &c->clean_list); 268 } 269 c->nextblock = NULL; 270 271 } 272 273 /* Select a new jeb for nextblock */ 274 275 static int jffs2_find_nextblock(struct jffs2_sb_info *c) 276 { 277 struct list_head *next; 278 279 /* Take the next block off the 'free' list */ 280 281 if (list_empty(&c->free_list)) { 282 283 if (!c->nr_erasing_blocks && 284 !list_empty(&c->erasable_list)) { 285 struct jffs2_eraseblock *ejeb; 286 287 ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list); 288 list_move_tail(&ejeb->list, &c->erase_pending_list); 289 c->nr_erasing_blocks++; 290 jffs2_garbage_collect_trigger(c); 291 jffs2_dbg(1, "%s(): Triggering erase of erasable block at 0x%08x\n", 292 __func__, ejeb->offset); 293 } 294 295 if (!c->nr_erasing_blocks && 296 !list_empty(&c->erasable_pending_wbuf_list)) { 297 jffs2_dbg(1, "%s(): Flushing write buffer\n", 298 __func__); 299 /* c->nextblock is NULL, no update to c->nextblock allowed */ 300 spin_unlock(&c->erase_completion_lock); 301 jffs2_flush_wbuf_pad(c); 302 spin_lock(&c->erase_completion_lock); 303 /* Have another go. It'll be on the erasable_list now */ 304 return -EAGAIN; 305 } 306 307 if (!c->nr_erasing_blocks) { 308 /* Ouch. We're in GC, or we wouldn't have got here. 309 And there's no space left. At all. */ 310 pr_crit("Argh. No free space left for GC. nr_erasing_blocks is %d. nr_free_blocks is %d. (erasableempty: %s, erasingempty: %s, erasependingempty: %s)\n", 311 c->nr_erasing_blocks, c->nr_free_blocks, 312 list_empty(&c->erasable_list) ? "yes" : "no", 313 list_empty(&c->erasing_list) ? "yes" : "no", 314 list_empty(&c->erase_pending_list) ? "yes" : "no"); 315 return -ENOSPC; 316 } 317 318 spin_unlock(&c->erase_completion_lock); 319 /* Don't wait for it; just erase one right now */ 320 jffs2_erase_pending_blocks(c, 1); 321 spin_lock(&c->erase_completion_lock); 322 323 /* An erase may have failed, decreasing the 324 amount of free space available. So we must 325 restart from the beginning */ 326 return -EAGAIN; 327 } 328 329 next = c->free_list.next; 330 list_del(next); 331 c->nextblock = list_entry(next, struct jffs2_eraseblock, list); 332 c->nr_free_blocks--; 333 334 jffs2_sum_reset_collected(c->summary); /* reset collected summary */ 335 336 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 337 /* adjust write buffer offset, else we get a non contiguous write bug */ 338 if (!(c->wbuf_ofs % c->sector_size) && !c->wbuf_len) 339 c->wbuf_ofs = 0xffffffff; 340 #endif 341 342 jffs2_dbg(1, "%s(): new nextblock = 0x%08x\n", 343 __func__, c->nextblock->offset); 344 345 return 0; 346 } 347 348 /* Called with alloc sem _and_ erase_completion_lock */ 349 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 350 uint32_t *len, uint32_t sumsize) 351 { 352 struct jffs2_eraseblock *jeb = c->nextblock; 353 uint32_t reserved_size; /* for summary information at the end of the jeb */ 354 int ret; 355 356 restart: 357 reserved_size = 0; 358 359 if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) { 360 /* NOSUM_SIZE means not to generate summary */ 361 362 if (jeb) { 363 reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE); 364 dbg_summary("minsize=%d , jeb->free=%d ," 365 "summary->size=%d , sumsize=%d\n", 366 minsize, jeb->free_size, 367 c->summary->sum_size, sumsize); 368 } 369 370 /* Is there enough space for writing out the current node, or we have to 371 write out summary information now, close this jeb and select new nextblock? */ 372 if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize + 373 JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) { 374 375 /* Has summary been disabled for this jeb? */ 376 if (jffs2_sum_is_disabled(c->summary)) { 377 sumsize = JFFS2_SUMMARY_NOSUM_SIZE; 378 goto restart; 379 } 380 381 /* Writing out the collected summary information */ 382 dbg_summary("generating summary for 0x%08x.\n", jeb->offset); 383 ret = jffs2_sum_write_sumnode(c); 384 385 if (ret) 386 return ret; 387 388 if (jffs2_sum_is_disabled(c->summary)) { 389 /* jffs2_write_sumnode() couldn't write out the summary information 390 diabling summary for this jeb and free the collected information 391 */ 392 sumsize = JFFS2_SUMMARY_NOSUM_SIZE; 393 goto restart; 394 } 395 396 jffs2_close_nextblock(c, jeb); 397 jeb = NULL; 398 /* keep always valid value in reserved_size */ 399 reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE); 400 } 401 } else { 402 if (jeb && minsize > jeb->free_size) { 403 uint32_t waste; 404 405 /* Skip the end of this block and file it as having some dirty space */ 406 /* If there's a pending write to it, flush now */ 407 408 if (jffs2_wbuf_dirty(c)) { 409 spin_unlock(&c->erase_completion_lock); 410 jffs2_dbg(1, "%s(): Flushing write buffer\n", 411 __func__); 412 jffs2_flush_wbuf_pad(c); 413 spin_lock(&c->erase_completion_lock); 414 jeb = c->nextblock; 415 goto restart; 416 } 417 418 spin_unlock(&c->erase_completion_lock); 419 420 ret = jffs2_prealloc_raw_node_refs(c, jeb, 1); 421 422 /* Just lock it again and continue. Nothing much can change because 423 we hold c->alloc_sem anyway. In fact, it's not entirely clear why 424 we hold c->erase_completion_lock in the majority of this function... 425 but that's a question for another (more caffeine-rich) day. */ 426 spin_lock(&c->erase_completion_lock); 427 428 if (ret) 429 return ret; 430 431 waste = jeb->free_size; 432 jffs2_link_node_ref(c, jeb, 433 (jeb->offset + c->sector_size - waste) | REF_OBSOLETE, 434 waste, NULL); 435 /* FIXME: that made it count as dirty. Convert to wasted */ 436 jeb->dirty_size -= waste; 437 c->dirty_size -= waste; 438 jeb->wasted_size += waste; 439 c->wasted_size += waste; 440 441 jffs2_close_nextblock(c, jeb); 442 jeb = NULL; 443 } 444 } 445 446 if (!jeb) { 447 448 ret = jffs2_find_nextblock(c); 449 if (ret) 450 return ret; 451 452 jeb = c->nextblock; 453 454 if (jeb->free_size != c->sector_size - c->cleanmarker_size) { 455 pr_warn("Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", 456 jeb->offset, jeb->free_size); 457 goto restart; 458 } 459 } 460 /* OK, jeb (==c->nextblock) is now pointing at a block which definitely has 461 enough space */ 462 *len = jeb->free_size - reserved_size; 463 464 if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size && 465 !jeb->first_node->next_in_ino) { 466 /* Only node in it beforehand was a CLEANMARKER node (we think). 467 So mark it obsolete now that there's going to be another node 468 in the block. This will reduce used_size to zero but We've 469 already set c->nextblock so that jffs2_mark_node_obsolete() 470 won't try to refile it to the dirty_list. 471 */ 472 spin_unlock(&c->erase_completion_lock); 473 jffs2_mark_node_obsolete(c, jeb->first_node); 474 spin_lock(&c->erase_completion_lock); 475 } 476 477 jffs2_dbg(1, "%s(): Giving 0x%x bytes at 0x%x\n", 478 __func__, 479 *len, jeb->offset + (c->sector_size - jeb->free_size)); 480 return 0; 481 } 482 483 /** 484 * jffs2_add_physical_node_ref - add a physical node reference to the list 485 * @c: superblock info 486 * @new: new node reference to add 487 * @len: length of this physical node 488 * 489 * Should only be used to report nodes for which space has been allocated 490 * by jffs2_reserve_space. 491 * 492 * Must be called with the alloc_sem held. 493 */ 494 495 struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c, 496 uint32_t ofs, uint32_t len, 497 struct jffs2_inode_cache *ic) 498 { 499 struct jffs2_eraseblock *jeb; 500 struct jffs2_raw_node_ref *new; 501 502 jeb = &c->blocks[ofs / c->sector_size]; 503 504 jffs2_dbg(1, "%s(): Node at 0x%x(%d), size 0x%x\n", 505 __func__, ofs & ~3, ofs & 3, len); 506 #if 1 507 /* Allow non-obsolete nodes only to be added at the end of c->nextblock, 508 if c->nextblock is set. Note that wbuf.c will file obsolete nodes 509 even after refiling c->nextblock */ 510 if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE)) 511 && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) { 512 pr_warn("argh. node added in wrong place at 0x%08x(%d)\n", 513 ofs & ~3, ofs & 3); 514 if (c->nextblock) 515 pr_warn("nextblock 0x%08x", c->nextblock->offset); 516 else 517 pr_warn("No nextblock"); 518 pr_cont(", expected at %08x\n", 519 jeb->offset + (c->sector_size - jeb->free_size)); 520 return ERR_PTR(-EINVAL); 521 } 522 #endif 523 spin_lock(&c->erase_completion_lock); 524 525 new = jffs2_link_node_ref(c, jeb, ofs, len, ic); 526 527 if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) { 528 /* If it lives on the dirty_list, jffs2_reserve_space will put it there */ 529 jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 530 jeb->offset, jeb->free_size, jeb->dirty_size, 531 jeb->used_size); 532 if (jffs2_wbuf_dirty(c)) { 533 /* Flush the last write in the block if it's outstanding */ 534 spin_unlock(&c->erase_completion_lock); 535 jffs2_flush_wbuf_pad(c); 536 spin_lock(&c->erase_completion_lock); 537 } 538 539 list_add_tail(&jeb->list, &c->clean_list); 540 c->nextblock = NULL; 541 } 542 jffs2_dbg_acct_sanity_check_nolock(c,jeb); 543 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 544 545 spin_unlock(&c->erase_completion_lock); 546 547 return new; 548 } 549 550 551 void jffs2_complete_reservation(struct jffs2_sb_info *c) 552 { 553 jffs2_dbg(1, "jffs2_complete_reservation()\n"); 554 spin_lock(&c->erase_completion_lock); 555 jffs2_garbage_collect_trigger(c); 556 spin_unlock(&c->erase_completion_lock); 557 mutex_unlock(&c->alloc_sem); 558 } 559 560 static inline int on_list(struct list_head *obj, struct list_head *head) 561 { 562 struct list_head *this; 563 564 list_for_each(this, head) { 565 if (this == obj) { 566 jffs2_dbg(1, "%p is on list at %p\n", obj, head); 567 return 1; 568 569 } 570 } 571 return 0; 572 } 573 574 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref) 575 { 576 struct jffs2_eraseblock *jeb; 577 int blocknr; 578 struct jffs2_unknown_node n; 579 int ret, addedsize; 580 size_t retlen; 581 uint32_t freed_len; 582 583 if(unlikely(!ref)) { 584 pr_notice("EEEEEK. jffs2_mark_node_obsolete called with NULL node\n"); 585 return; 586 } 587 if (ref_obsolete(ref)) { 588 jffs2_dbg(1, "%s(): called with already obsolete node at 0x%08x\n", 589 __func__, ref_offset(ref)); 590 return; 591 } 592 blocknr = ref->flash_offset / c->sector_size; 593 if (blocknr >= c->nr_blocks) { 594 pr_notice("raw node at 0x%08x is off the end of device!\n", 595 ref->flash_offset); 596 BUG(); 597 } 598 jeb = &c->blocks[blocknr]; 599 600 if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) && 601 !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) { 602 /* Hm. This may confuse static lock analysis. If any of the above 603 three conditions is false, we're going to return from this 604 function without actually obliterating any nodes or freeing 605 any jffs2_raw_node_refs. So we don't need to stop erases from 606 happening, or protect against people holding an obsolete 607 jffs2_raw_node_ref without the erase_completion_lock. */ 608 mutex_lock(&c->erase_free_sem); 609 } 610 611 spin_lock(&c->erase_completion_lock); 612 613 freed_len = ref_totlen(c, jeb, ref); 614 615 if (ref_flags(ref) == REF_UNCHECKED) { 616 D1(if (unlikely(jeb->unchecked_size < freed_len)) { 617 pr_notice("raw unchecked node of size 0x%08x freed from erase block %d at 0x%08x, but unchecked_size was already 0x%08x\n", 618 freed_len, blocknr, 619 ref->flash_offset, jeb->used_size); 620 BUG(); 621 }) 622 jffs2_dbg(1, "Obsoleting previously unchecked node at 0x%08x of len %x\n", 623 ref_offset(ref), freed_len); 624 jeb->unchecked_size -= freed_len; 625 c->unchecked_size -= freed_len; 626 } else { 627 D1(if (unlikely(jeb->used_size < freed_len)) { 628 pr_notice("raw node of size 0x%08x freed from erase block %d at 0x%08x, but used_size was already 0x%08x\n", 629 freed_len, blocknr, 630 ref->flash_offset, jeb->used_size); 631 BUG(); 632 }) 633 jffs2_dbg(1, "Obsoleting node at 0x%08x of len %#x: ", 634 ref_offset(ref), freed_len); 635 jeb->used_size -= freed_len; 636 c->used_size -= freed_len; 637 } 638 639 // Take care, that wasted size is taken into concern 640 if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) { 641 jffs2_dbg(1, "Dirtying\n"); 642 addedsize = freed_len; 643 jeb->dirty_size += freed_len; 644 c->dirty_size += freed_len; 645 646 /* Convert wasted space to dirty, if not a bad block */ 647 if (jeb->wasted_size) { 648 if (on_list(&jeb->list, &c->bad_used_list)) { 649 jffs2_dbg(1, "Leaving block at %08x on the bad_used_list\n", 650 jeb->offset); 651 addedsize = 0; /* To fool the refiling code later */ 652 } else { 653 jffs2_dbg(1, "Converting %d bytes of wasted space to dirty in block at %08x\n", 654 jeb->wasted_size, jeb->offset); 655 addedsize += jeb->wasted_size; 656 jeb->dirty_size += jeb->wasted_size; 657 c->dirty_size += jeb->wasted_size; 658 c->wasted_size -= jeb->wasted_size; 659 jeb->wasted_size = 0; 660 } 661 } 662 } else { 663 jffs2_dbg(1, "Wasting\n"); 664 addedsize = 0; 665 jeb->wasted_size += freed_len; 666 c->wasted_size += freed_len; 667 } 668 ref->flash_offset = ref_offset(ref) | REF_OBSOLETE; 669 670 jffs2_dbg_acct_sanity_check_nolock(c, jeb); 671 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 672 673 if (c->flags & JFFS2_SB_FLAG_SCANNING) { 674 /* Flash scanning is in progress. Don't muck about with the block 675 lists because they're not ready yet, and don't actually 676 obliterate nodes that look obsolete. If they weren't 677 marked obsolete on the flash at the time they _became_ 678 obsolete, there was probably a reason for that. */ 679 spin_unlock(&c->erase_completion_lock); 680 /* We didn't lock the erase_free_sem */ 681 return; 682 } 683 684 if (jeb == c->nextblock) { 685 jffs2_dbg(2, "Not moving nextblock 0x%08x to dirty/erase_pending list\n", 686 jeb->offset); 687 } else if (!jeb->used_size && !jeb->unchecked_size) { 688 if (jeb == c->gcblock) { 689 jffs2_dbg(1, "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n", 690 jeb->offset); 691 c->gcblock = NULL; 692 } else { 693 jffs2_dbg(1, "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n", 694 jeb->offset); 695 list_del(&jeb->list); 696 } 697 if (jffs2_wbuf_dirty(c)) { 698 jffs2_dbg(1, "...and adding to erasable_pending_wbuf_list\n"); 699 list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list); 700 } else { 701 if (jiffies & 127) { 702 /* Most of the time, we just erase it immediately. Otherwise we 703 spend ages scanning it on mount, etc. */ 704 jffs2_dbg(1, "...and adding to erase_pending_list\n"); 705 list_add_tail(&jeb->list, &c->erase_pending_list); 706 c->nr_erasing_blocks++; 707 jffs2_garbage_collect_trigger(c); 708 } else { 709 /* Sometimes, however, we leave it elsewhere so it doesn't get 710 immediately reused, and we spread the load a bit. */ 711 jffs2_dbg(1, "...and adding to erasable_list\n"); 712 list_add_tail(&jeb->list, &c->erasable_list); 713 } 714 } 715 jffs2_dbg(1, "Done OK\n"); 716 } else if (jeb == c->gcblock) { 717 jffs2_dbg(2, "Not moving gcblock 0x%08x to dirty_list\n", 718 jeb->offset); 719 } else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) { 720 jffs2_dbg(1, "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n", 721 jeb->offset); 722 list_del(&jeb->list); 723 jffs2_dbg(1, "...and adding to dirty_list\n"); 724 list_add_tail(&jeb->list, &c->dirty_list); 725 } else if (VERYDIRTY(c, jeb->dirty_size) && 726 !VERYDIRTY(c, jeb->dirty_size - addedsize)) { 727 jffs2_dbg(1, "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n", 728 jeb->offset); 729 list_del(&jeb->list); 730 jffs2_dbg(1, "...and adding to very_dirty_list\n"); 731 list_add_tail(&jeb->list, &c->very_dirty_list); 732 } else { 733 jffs2_dbg(1, "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n", 734 jeb->offset, jeb->free_size, jeb->dirty_size, 735 jeb->used_size); 736 } 737 738 spin_unlock(&c->erase_completion_lock); 739 740 if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) || 741 (c->flags & JFFS2_SB_FLAG_BUILDING)) { 742 /* We didn't lock the erase_free_sem */ 743 return; 744 } 745 746 /* The erase_free_sem is locked, and has been since before we marked the node obsolete 747 and potentially put its eraseblock onto the erase_pending_list. Thus, we know that 748 the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet 749 by jffs2_free_jeb_node_refs() in erase.c. Which is nice. */ 750 751 jffs2_dbg(1, "obliterating obsoleted node at 0x%08x\n", 752 ref_offset(ref)); 753 ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n); 754 if (ret) { 755 pr_warn("Read error reading from obsoleted node at 0x%08x: %d\n", 756 ref_offset(ref), ret); 757 goto out_erase_sem; 758 } 759 if (retlen != sizeof(n)) { 760 pr_warn("Short read from obsoleted node at 0x%08x: %zd\n", 761 ref_offset(ref), retlen); 762 goto out_erase_sem; 763 } 764 if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) { 765 pr_warn("Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n", 766 je32_to_cpu(n.totlen), freed_len); 767 goto out_erase_sem; 768 } 769 if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) { 770 jffs2_dbg(1, "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n", 771 ref_offset(ref), je16_to_cpu(n.nodetype)); 772 goto out_erase_sem; 773 } 774 /* XXX FIXME: This is ugly now */ 775 n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE); 776 ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n); 777 if (ret) { 778 pr_warn("Write error in obliterating obsoleted node at 0x%08x: %d\n", 779 ref_offset(ref), ret); 780 goto out_erase_sem; 781 } 782 if (retlen != sizeof(n)) { 783 pr_warn("Short write in obliterating obsoleted node at 0x%08x: %zd\n", 784 ref_offset(ref), retlen); 785 goto out_erase_sem; 786 } 787 788 /* Nodes which have been marked obsolete no longer need to be 789 associated with any inode. Remove them from the per-inode list. 790 791 Note we can't do this for NAND at the moment because we need 792 obsolete dirent nodes to stay on the lists, because of the 793 horridness in jffs2_garbage_collect_deletion_dirent(). Also 794 because we delete the inocache, and on NAND we need that to 795 stay around until all the nodes are actually erased, in order 796 to stop us from giving the same inode number to another newly 797 created inode. */ 798 if (ref->next_in_ino) { 799 struct jffs2_inode_cache *ic; 800 struct jffs2_raw_node_ref **p; 801 802 spin_lock(&c->erase_completion_lock); 803 804 ic = jffs2_raw_ref_to_ic(ref); 805 for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino)) 806 ; 807 808 *p = ref->next_in_ino; 809 ref->next_in_ino = NULL; 810 811 switch (ic->class) { 812 #ifdef CONFIG_JFFS2_FS_XATTR 813 case RAWNODE_CLASS_XATTR_DATUM: 814 jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic); 815 break; 816 case RAWNODE_CLASS_XATTR_REF: 817 jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic); 818 break; 819 #endif 820 default: 821 if (ic->nodes == (void *)ic && ic->pino_nlink == 0) 822 jffs2_del_ino_cache(c, ic); 823 break; 824 } 825 spin_unlock(&c->erase_completion_lock); 826 } 827 828 out_erase_sem: 829 mutex_unlock(&c->erase_free_sem); 830 } 831 832 int jffs2_thread_should_wake(struct jffs2_sb_info *c) 833 { 834 int ret = 0; 835 uint32_t dirty; 836 int nr_very_dirty = 0; 837 struct jffs2_eraseblock *jeb; 838 839 if (!list_empty(&c->erase_complete_list) || 840 !list_empty(&c->erase_pending_list)) 841 return 1; 842 843 if (c->unchecked_size) { 844 jffs2_dbg(1, "jffs2_thread_should_wake(): unchecked_size %d, checked_ino #%d\n", 845 c->unchecked_size, c->checked_ino); 846 return 1; 847 } 848 849 /* dirty_size contains blocks on erase_pending_list 850 * those blocks are counted in c->nr_erasing_blocks. 851 * If one block is actually erased, it is not longer counted as dirty_space 852 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it 853 * with c->nr_erasing_blocks * c->sector_size again. 854 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks 855 * This helps us to force gc and pick eventually a clean block to spread the load. 856 */ 857 dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size; 858 859 if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger && 860 (dirty > c->nospc_dirty_size)) 861 ret = 1; 862 863 list_for_each_entry(jeb, &c->very_dirty_list, list) { 864 nr_very_dirty++; 865 if (nr_very_dirty == c->vdirty_blocks_gctrigger) { 866 ret = 1; 867 /* In debug mode, actually go through and count them all */ 868 D1(continue); 869 break; 870 } 871 } 872 873 jffs2_dbg(1, "%s(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x, vdirty_blocks %d: %s\n", 874 __func__, c->nr_free_blocks, c->nr_erasing_blocks, 875 c->dirty_size, nr_very_dirty, ret ? "yes" : "no"); 876 877 return ret; 878 } 879