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/signal.h> 18 #include <linux/string_choices.h> 19 #include "nodelist.h" 20 #include "debug.h" 21 22 /* 23 * Check whether the user is allowed to write. 24 */ 25 static int jffs2_rp_can_write(struct jffs2_sb_info *c) 26 { 27 uint32_t avail; 28 struct jffs2_mount_opts *opts = &c->mount_opts; 29 30 avail = c->dirty_size + c->free_size + c->unchecked_size + 31 c->erasing_size - c->resv_blocks_write * c->sector_size 32 - c->nospc_dirty_size; 33 34 if (avail < 2 * opts->rp_size) 35 jffs2_dbg(1, "rpsize %u, dirty_size %u, free_size %u, " 36 "erasing_size %u, unchecked_size %u, " 37 "nr_erasing_blocks %u, avail %u, resrv %u\n", 38 opts->rp_size, c->dirty_size, c->free_size, 39 c->erasing_size, c->unchecked_size, 40 c->nr_erasing_blocks, avail, c->nospc_dirty_size); 41 42 if (avail > opts->rp_size) 43 return 1; 44 45 /* Always allow root */ 46 if (capable(CAP_SYS_RESOURCE)) 47 return 1; 48 49 jffs2_dbg(1, "forbid writing\n"); 50 return 0; 51 } 52 53 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 54 uint32_t *len, uint32_t sumsize); 55 56 /** 57 * jffs2_reserve_space - request physical space to write nodes to flash 58 * @c: superblock info 59 * @minsize: Minimum acceptable size of allocation 60 * @len: Returned value of allocation length 61 * @prio: Allocation type - ALLOC_{NORMAL,DELETION} 62 * @sumsize: summary size requested or JFFS2_SUMMARY_NOSUM_SIZE for no summary 63 * 64 * Requests a block of physical space on the flash. 65 * 66 * Returns: %0 for success and puts 'len' into the appropriate place, 67 * or returns -ENOSPC or other error if appropriate. 68 * Doesn't return len since that's already returned in @len. 69 * 70 * If it returns %0, jffs2_reserve_space() also downs the per-filesystem 71 * allocation semaphore, to prevent more than one allocation from being 72 * active at any time. The semaphore is later released by jffs2_commit_allocation(). 73 * 74 * jffs2_reserve_space() may trigger garbage collection in order to make room 75 * for the requested allocation. 76 */ 77 78 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 79 uint32_t *len, int prio, uint32_t sumsize) 80 { 81 int ret = -EAGAIN; 82 int blocksneeded = c->resv_blocks_write; 83 /* align it */ 84 minsize = PAD(minsize); 85 86 jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize); 87 mutex_lock(&c->alloc_sem); 88 89 jffs2_dbg(1, "%s(): alloc sem got\n", __func__); 90 91 spin_lock(&c->erase_completion_lock); 92 93 /* 94 * Check if the free space is greater then size of the reserved pool. 95 * If not, only allow root to proceed with writing. 96 */ 97 if (prio != ALLOC_DELETION && !jffs2_rp_can_write(c)) { 98 ret = -ENOSPC; 99 goto out; 100 } 101 102 /* this needs a little more thought (true <tglx> :)) */ 103 while(ret == -EAGAIN) { 104 while(c->nr_free_blocks + c->nr_erasing_blocks < blocksneeded) { 105 uint32_t dirty, avail; 106 107 /* calculate real dirty size 108 * dirty_size contains blocks on erase_pending_list 109 * those blocks are counted in c->nr_erasing_blocks. 110 * If one block is actually erased, it is not longer counted as dirty_space 111 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it 112 * with c->nr_erasing_blocks * c->sector_size again. 113 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks 114 * This helps us to force gc and pick eventually a clean block to spread the load. 115 * We add unchecked_size here, as we hopefully will find some space to use. 116 * This will affect the sum only once, as gc first finishes checking 117 * of nodes. 118 */ 119 dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size + c->unchecked_size; 120 if (dirty < c->nospc_dirty_size) { 121 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) { 122 jffs2_dbg(1, "%s(): Low on dirty space to GC, but it's a deletion. Allowing...\n", 123 __func__); 124 break; 125 } 126 jffs2_dbg(1, "dirty size 0x%08x + unchecked_size 0x%08x < nospc_dirty_size 0x%08x, returning -ENOSPC\n", 127 dirty, c->unchecked_size, 128 c->sector_size); 129 130 spin_unlock(&c->erase_completion_lock); 131 mutex_unlock(&c->alloc_sem); 132 return -ENOSPC; 133 } 134 135 /* Calc possibly available space. Possibly available means that we 136 * don't know, if unchecked size contains obsoleted nodes, which could give us some 137 * more usable space. This will affect the sum only once, as gc first finishes checking 138 * of nodes. 139 + Return -ENOSPC, if the maximum possibly available space is less or equal than 140 * blocksneeded * sector_size. 141 * This blocks endless gc looping on a filesystem, which is nearly full, even if 142 * the check above passes. 143 */ 144 avail = c->free_size + c->dirty_size + c->erasing_size + c->unchecked_size; 145 if ( (avail / c->sector_size) <= blocksneeded) { 146 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) { 147 jffs2_dbg(1, "%s(): Low on possibly available space, but it's a deletion. Allowing...\n", 148 __func__); 149 break; 150 } 151 152 jffs2_dbg(1, "max. available size 0x%08x < blocksneeded * sector_size 0x%08x, returning -ENOSPC\n", 153 avail, blocksneeded * c->sector_size); 154 spin_unlock(&c->erase_completion_lock); 155 mutex_unlock(&c->alloc_sem); 156 return -ENOSPC; 157 } 158 159 mutex_unlock(&c->alloc_sem); 160 161 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", 162 c->nr_free_blocks, c->nr_erasing_blocks, 163 c->free_size, c->dirty_size, c->wasted_size, 164 c->used_size, c->erasing_size, c->bad_size, 165 c->free_size + c->dirty_size + 166 c->wasted_size + c->used_size + 167 c->erasing_size + c->bad_size, 168 c->flash_size); 169 spin_unlock(&c->erase_completion_lock); 170 171 ret = jffs2_garbage_collect_pass(c); 172 173 if (ret == -EAGAIN) { 174 spin_lock(&c->erase_completion_lock); 175 if (c->nr_erasing_blocks && 176 list_empty(&c->erase_pending_list) && 177 list_empty(&c->erase_complete_list)) { 178 DECLARE_WAITQUEUE(wait, current); 179 set_current_state(TASK_UNINTERRUPTIBLE); 180 add_wait_queue(&c->erase_wait, &wait); 181 jffs2_dbg(1, "%s waiting for erase to complete\n", 182 __func__); 183 spin_unlock(&c->erase_completion_lock); 184 185 schedule(); 186 remove_wait_queue(&c->erase_wait, &wait); 187 } else 188 spin_unlock(&c->erase_completion_lock); 189 } else if (ret) 190 return ret; 191 192 cond_resched(); 193 194 if (signal_pending(current)) 195 return -EINTR; 196 197 mutex_lock(&c->alloc_sem); 198 spin_lock(&c->erase_completion_lock); 199 } 200 201 ret = jffs2_do_reserve_space(c, minsize, len, sumsize); 202 if (ret) { 203 jffs2_dbg(1, "%s(): ret is %d\n", __func__, ret); 204 } 205 } 206 207 out: 208 spin_unlock(&c->erase_completion_lock); 209 if (!ret) 210 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1); 211 if (ret) 212 mutex_unlock(&c->alloc_sem); 213 return ret; 214 } 215 216 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize, 217 uint32_t *len, uint32_t sumsize) 218 { 219 int ret; 220 minsize = PAD(minsize); 221 222 jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize); 223 224 while (true) { 225 spin_lock(&c->erase_completion_lock); 226 ret = jffs2_do_reserve_space(c, minsize, len, sumsize); 227 if (ret) { 228 jffs2_dbg(1, "%s(): looping, ret is %d\n", 229 __func__, ret); 230 } 231 spin_unlock(&c->erase_completion_lock); 232 233 if (ret == -EAGAIN) 234 cond_resched(); 235 else 236 break; 237 } 238 if (!ret) 239 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1); 240 241 return ret; 242 } 243 244 245 /* Classify nextblock (clean, dirty of verydirty) and force to select an other one */ 246 247 static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) 248 { 249 250 if (c->nextblock == NULL) { 251 jffs2_dbg(1, "%s(): Erase block at 0x%08x has already been placed in a list\n", 252 __func__, jeb->offset); 253 return; 254 } 255 /* Check, if we have a dirty block now, or if it was dirty already */ 256 if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) { 257 c->dirty_size += jeb->wasted_size; 258 c->wasted_size -= jeb->wasted_size; 259 jeb->dirty_size += jeb->wasted_size; 260 jeb->wasted_size = 0; 261 if (VERYDIRTY(c, jeb->dirty_size)) { 262 jffs2_dbg(1, "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 263 jeb->offset, jeb->free_size, jeb->dirty_size, 264 jeb->used_size); 265 list_add_tail(&jeb->list, &c->very_dirty_list); 266 } else { 267 jffs2_dbg(1, "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 268 jeb->offset, jeb->free_size, jeb->dirty_size, 269 jeb->used_size); 270 list_add_tail(&jeb->list, &c->dirty_list); 271 } 272 } else { 273 jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 274 jeb->offset, jeb->free_size, jeb->dirty_size, 275 jeb->used_size); 276 list_add_tail(&jeb->list, &c->clean_list); 277 } 278 c->nextblock = NULL; 279 280 } 281 282 /* Select a new jeb for nextblock */ 283 284 static int jffs2_find_nextblock(struct jffs2_sb_info *c) 285 { 286 struct list_head *next; 287 288 /* Take the next block off the 'free' list */ 289 290 if (list_empty(&c->free_list)) { 291 292 if (!c->nr_erasing_blocks && 293 !list_empty(&c->erasable_list)) { 294 struct jffs2_eraseblock *ejeb; 295 296 ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list); 297 list_move_tail(&ejeb->list, &c->erase_pending_list); 298 c->nr_erasing_blocks++; 299 jffs2_garbage_collect_trigger(c); 300 jffs2_dbg(1, "%s(): Triggering erase of erasable block at 0x%08x\n", 301 __func__, ejeb->offset); 302 } 303 304 if (!c->nr_erasing_blocks && 305 !list_empty(&c->erasable_pending_wbuf_list)) { 306 jffs2_dbg(1, "%s(): Flushing write buffer\n", 307 __func__); 308 /* c->nextblock is NULL, no update to c->nextblock allowed */ 309 spin_unlock(&c->erase_completion_lock); 310 jffs2_flush_wbuf_pad(c); 311 spin_lock(&c->erase_completion_lock); 312 /* Have another go. It'll be on the erasable_list now */ 313 return -EAGAIN; 314 } 315 316 if (!c->nr_erasing_blocks) { 317 /* Ouch. We're in GC, or we wouldn't have got here. 318 And there's no space left. At all. */ 319 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", 320 c->nr_erasing_blocks, c->nr_free_blocks, 321 str_yes_no(list_empty(&c->erasable_list)), 322 str_yes_no(list_empty(&c->erasing_list)), 323 str_yes_no(list_empty(&c->erase_pending_list))); 324 return -ENOSPC; 325 } 326 327 spin_unlock(&c->erase_completion_lock); 328 /* Don't wait for it; just erase one right now */ 329 jffs2_erase_pending_blocks(c, 1); 330 spin_lock(&c->erase_completion_lock); 331 332 /* An erase may have failed, decreasing the 333 amount of free space available. So we must 334 restart from the beginning */ 335 return -EAGAIN; 336 } 337 338 next = c->free_list.next; 339 list_del(next); 340 c->nextblock = list_entry(next, struct jffs2_eraseblock, list); 341 c->nr_free_blocks--; 342 343 jffs2_sum_reset_collected(c->summary); /* reset collected summary */ 344 345 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER 346 /* adjust write buffer offset, else we get a non contiguous write bug */ 347 if (!(c->wbuf_ofs % c->sector_size) && !c->wbuf_len) 348 c->wbuf_ofs = 0xffffffff; 349 #endif 350 351 jffs2_dbg(1, "%s(): new nextblock = 0x%08x\n", 352 __func__, c->nextblock->offset); 353 354 return 0; 355 } 356 357 /* Called with alloc sem _and_ erase_completion_lock */ 358 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize, 359 uint32_t *len, uint32_t sumsize) 360 { 361 struct jffs2_eraseblock *jeb = c->nextblock; 362 uint32_t reserved_size; /* for summary information at the end of the jeb */ 363 int ret; 364 365 restart: 366 reserved_size = 0; 367 368 if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) { 369 /* NOSUM_SIZE means not to generate summary */ 370 371 if (jeb) { 372 reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE); 373 dbg_summary("minsize=%d , jeb->free=%d ," 374 "summary->size=%d , sumsize=%d\n", 375 minsize, jeb->free_size, 376 c->summary->sum_size, sumsize); 377 } 378 379 /* Is there enough space for writing out the current node, or we have to 380 write out summary information now, close this jeb and select new nextblock? */ 381 if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize + 382 JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) { 383 384 /* Has summary been disabled for this jeb? */ 385 if (jffs2_sum_is_disabled(c->summary)) { 386 sumsize = JFFS2_SUMMARY_NOSUM_SIZE; 387 goto restart; 388 } 389 390 /* Writing out the collected summary information */ 391 dbg_summary("generating summary for 0x%08x.\n", jeb->offset); 392 ret = jffs2_sum_write_sumnode(c); 393 394 if (ret) 395 return ret; 396 397 if (jffs2_sum_is_disabled(c->summary)) { 398 /* jffs2_write_sumnode() couldn't write out the summary information 399 diabling summary for this jeb and free the collected information 400 */ 401 sumsize = JFFS2_SUMMARY_NOSUM_SIZE; 402 goto restart; 403 } 404 405 jffs2_close_nextblock(c, jeb); 406 jeb = NULL; 407 /* keep always valid value in reserved_size */ 408 reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE); 409 } 410 } else { 411 if (jeb && minsize > jeb->free_size) { 412 uint32_t waste; 413 414 /* Skip the end of this block and file it as having some dirty space */ 415 /* If there's a pending write to it, flush now */ 416 417 if (jffs2_wbuf_dirty(c)) { 418 spin_unlock(&c->erase_completion_lock); 419 jffs2_dbg(1, "%s(): Flushing write buffer\n", 420 __func__); 421 jffs2_flush_wbuf_pad(c); 422 spin_lock(&c->erase_completion_lock); 423 jeb = c->nextblock; 424 goto restart; 425 } 426 427 spin_unlock(&c->erase_completion_lock); 428 429 ret = jffs2_prealloc_raw_node_refs(c, jeb, 1); 430 431 /* Just lock it again and continue. Nothing much can change because 432 we hold c->alloc_sem anyway. In fact, it's not entirely clear why 433 we hold c->erase_completion_lock in the majority of this function... 434 but that's a question for another (more caffeine-rich) day. */ 435 spin_lock(&c->erase_completion_lock); 436 437 if (ret) 438 return ret; 439 440 waste = jeb->free_size; 441 jffs2_link_node_ref(c, jeb, 442 (jeb->offset + c->sector_size - waste) | REF_OBSOLETE, 443 waste, NULL); 444 /* FIXME: that made it count as dirty. Convert to wasted */ 445 jeb->dirty_size -= waste; 446 c->dirty_size -= waste; 447 jeb->wasted_size += waste; 448 c->wasted_size += waste; 449 450 jffs2_close_nextblock(c, jeb); 451 jeb = NULL; 452 } 453 } 454 455 if (!jeb) { 456 457 ret = jffs2_find_nextblock(c); 458 if (ret) 459 return ret; 460 461 jeb = c->nextblock; 462 463 if (jeb->free_size != c->sector_size - c->cleanmarker_size) { 464 pr_warn("Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", 465 jeb->offset, jeb->free_size); 466 goto restart; 467 } 468 } 469 /* OK, jeb (==c->nextblock) is now pointing at a block which definitely has 470 enough space */ 471 *len = jeb->free_size - reserved_size; 472 473 if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size && 474 !jeb->first_node->next_in_ino) { 475 /* Only node in it beforehand was a CLEANMARKER node (we think). 476 So mark it obsolete now that there's going to be another node 477 in the block. This will reduce used_size to zero but We've 478 already set c->nextblock so that jffs2_mark_node_obsolete() 479 won't try to refile it to the dirty_list. 480 */ 481 spin_unlock(&c->erase_completion_lock); 482 jffs2_mark_node_obsolete(c, jeb->first_node); 483 spin_lock(&c->erase_completion_lock); 484 } 485 486 jffs2_dbg(1, "%s(): Giving 0x%x bytes at 0x%x\n", 487 __func__, 488 *len, jeb->offset + (c->sector_size - jeb->free_size)); 489 return 0; 490 } 491 492 /** 493 * jffs2_add_physical_node_ref - add a physical node reference to the list 494 * @c: superblock info 495 * @ofs: offset in the block 496 * @len: length of this physical node 497 * @ic: inode cache pointer 498 * 499 * Should only be used to report nodes for which space has been allocated 500 * by jffs2_reserve_space. 501 * 502 * Must be called with the alloc_sem held. 503 * 504 * Returns: pointer to new node on success or -errno code on error 505 */ 506 507 struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c, 508 uint32_t ofs, uint32_t len, 509 struct jffs2_inode_cache *ic) 510 { 511 struct jffs2_eraseblock *jeb; 512 struct jffs2_raw_node_ref *new; 513 514 jeb = &c->blocks[ofs / c->sector_size]; 515 516 jffs2_dbg(1, "%s(): Node at 0x%x(%d), size 0x%x\n", 517 __func__, ofs & ~3, ofs & 3, len); 518 #if 1 519 /* Allow non-obsolete nodes only to be added at the end of c->nextblock, 520 if c->nextblock is set. Note that wbuf.c will file obsolete nodes 521 even after refiling c->nextblock */ 522 if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE)) 523 && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) { 524 pr_warn("argh. node added in wrong place at 0x%08x(%d)\n", 525 ofs & ~3, ofs & 3); 526 if (c->nextblock) 527 pr_warn("nextblock 0x%08x", c->nextblock->offset); 528 else 529 pr_warn("No nextblock"); 530 pr_cont(", expected at %08x\n", 531 jeb->offset + (c->sector_size - jeb->free_size)); 532 return ERR_PTR(-EINVAL); 533 } 534 #endif 535 spin_lock(&c->erase_completion_lock); 536 537 new = jffs2_link_node_ref(c, jeb, ofs, len, ic); 538 539 if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) { 540 /* If it lives on the dirty_list, jffs2_reserve_space will put it there */ 541 jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n", 542 jeb->offset, jeb->free_size, jeb->dirty_size, 543 jeb->used_size); 544 if (jffs2_wbuf_dirty(c)) { 545 /* Flush the last write in the block if it's outstanding */ 546 spin_unlock(&c->erase_completion_lock); 547 jffs2_flush_wbuf_pad(c); 548 spin_lock(&c->erase_completion_lock); 549 } 550 551 list_add_tail(&jeb->list, &c->clean_list); 552 c->nextblock = NULL; 553 } 554 jffs2_dbg_acct_sanity_check_nolock(c,jeb); 555 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 556 557 spin_unlock(&c->erase_completion_lock); 558 559 return new; 560 } 561 562 563 void jffs2_complete_reservation(struct jffs2_sb_info *c) 564 { 565 jffs2_dbg(1, "jffs2_complete_reservation()\n"); 566 spin_lock(&c->erase_completion_lock); 567 jffs2_garbage_collect_trigger(c); 568 spin_unlock(&c->erase_completion_lock); 569 mutex_unlock(&c->alloc_sem); 570 } 571 572 static inline int on_list(struct list_head *obj, struct list_head *head) 573 { 574 struct list_head *this; 575 576 list_for_each(this, head) { 577 if (this == obj) { 578 jffs2_dbg(1, "%p is on list at %p\n", obj, head); 579 return 1; 580 581 } 582 } 583 return 0; 584 } 585 586 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref) 587 { 588 struct jffs2_eraseblock *jeb; 589 int blocknr; 590 struct jffs2_unknown_node n; 591 int ret, addedsize; 592 size_t retlen; 593 uint32_t freed_len; 594 595 if(unlikely(!ref)) { 596 pr_notice("EEEEEK. jffs2_mark_node_obsolete called with NULL node\n"); 597 return; 598 } 599 if (ref_obsolete(ref)) { 600 jffs2_dbg(1, "%s(): called with already obsolete node at 0x%08x\n", 601 __func__, ref_offset(ref)); 602 return; 603 } 604 blocknr = ref->flash_offset / c->sector_size; 605 if (blocknr >= c->nr_blocks) { 606 pr_notice("raw node at 0x%08x is off the end of device!\n", 607 ref->flash_offset); 608 BUG(); 609 } 610 jeb = &c->blocks[blocknr]; 611 612 if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) && 613 !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) { 614 /* Hm. This may confuse static lock analysis. If any of the above 615 three conditions is false, we're going to return from this 616 function without actually obliterating any nodes or freeing 617 any jffs2_raw_node_refs. So we don't need to stop erases from 618 happening, or protect against people holding an obsolete 619 jffs2_raw_node_ref without the erase_completion_lock. */ 620 mutex_lock(&c->erase_free_sem); 621 } 622 623 spin_lock(&c->erase_completion_lock); 624 625 freed_len = ref_totlen(c, jeb, ref); 626 627 if (ref_flags(ref) == REF_UNCHECKED) { 628 D1(if (unlikely(jeb->unchecked_size < freed_len)) { 629 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", 630 freed_len, blocknr, 631 ref->flash_offset, jeb->used_size); 632 BUG(); 633 }) 634 jffs2_dbg(1, "Obsoleting previously unchecked node at 0x%08x of len %x\n", 635 ref_offset(ref), freed_len); 636 jeb->unchecked_size -= freed_len; 637 c->unchecked_size -= freed_len; 638 } else { 639 D1(if (unlikely(jeb->used_size < freed_len)) { 640 pr_notice("raw node of size 0x%08x freed from erase block %d at 0x%08x, but used_size was already 0x%08x\n", 641 freed_len, blocknr, 642 ref->flash_offset, jeb->used_size); 643 BUG(); 644 }) 645 jffs2_dbg(1, "Obsoleting node at 0x%08x of len %#x: ", 646 ref_offset(ref), freed_len); 647 jeb->used_size -= freed_len; 648 c->used_size -= freed_len; 649 } 650 651 // Take care, that wasted size is taken into concern 652 if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) { 653 jffs2_dbg(1, "Dirtying\n"); 654 addedsize = freed_len; 655 jeb->dirty_size += freed_len; 656 c->dirty_size += freed_len; 657 658 /* Convert wasted space to dirty, if not a bad block */ 659 if (jeb->wasted_size) { 660 if (on_list(&jeb->list, &c->bad_used_list)) { 661 jffs2_dbg(1, "Leaving block at %08x on the bad_used_list\n", 662 jeb->offset); 663 addedsize = 0; /* To fool the refiling code later */ 664 } else { 665 jffs2_dbg(1, "Converting %d bytes of wasted space to dirty in block at %08x\n", 666 jeb->wasted_size, jeb->offset); 667 addedsize += jeb->wasted_size; 668 jeb->dirty_size += jeb->wasted_size; 669 c->dirty_size += jeb->wasted_size; 670 c->wasted_size -= jeb->wasted_size; 671 jeb->wasted_size = 0; 672 } 673 } 674 } else { 675 jffs2_dbg(1, "Wasting\n"); 676 addedsize = 0; 677 jeb->wasted_size += freed_len; 678 c->wasted_size += freed_len; 679 } 680 ref->flash_offset = ref_offset(ref) | REF_OBSOLETE; 681 682 jffs2_dbg_acct_sanity_check_nolock(c, jeb); 683 jffs2_dbg_acct_paranoia_check_nolock(c, jeb); 684 685 if (c->flags & JFFS2_SB_FLAG_SCANNING) { 686 /* Flash scanning is in progress. Don't muck about with the block 687 lists because they're not ready yet, and don't actually 688 obliterate nodes that look obsolete. If they weren't 689 marked obsolete on the flash at the time they _became_ 690 obsolete, there was probably a reason for that. */ 691 spin_unlock(&c->erase_completion_lock); 692 /* We didn't lock the erase_free_sem */ 693 return; 694 } 695 696 if (jeb == c->nextblock) { 697 jffs2_dbg(2, "Not moving nextblock 0x%08x to dirty/erase_pending list\n", 698 jeb->offset); 699 } else if (!jeb->used_size && !jeb->unchecked_size) { 700 if (jeb == c->gcblock) { 701 jffs2_dbg(1, "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n", 702 jeb->offset); 703 c->gcblock = NULL; 704 } else { 705 jffs2_dbg(1, "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n", 706 jeb->offset); 707 list_del(&jeb->list); 708 } 709 if (jffs2_wbuf_dirty(c)) { 710 jffs2_dbg(1, "...and adding to erasable_pending_wbuf_list\n"); 711 list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list); 712 } else { 713 if (jiffies & 127) { 714 /* Most of the time, we just erase it immediately. Otherwise we 715 spend ages scanning it on mount, etc. */ 716 jffs2_dbg(1, "...and adding to erase_pending_list\n"); 717 list_add_tail(&jeb->list, &c->erase_pending_list); 718 c->nr_erasing_blocks++; 719 jffs2_garbage_collect_trigger(c); 720 } else { 721 /* Sometimes, however, we leave it elsewhere so it doesn't get 722 immediately reused, and we spread the load a bit. */ 723 jffs2_dbg(1, "...and adding to erasable_list\n"); 724 list_add_tail(&jeb->list, &c->erasable_list); 725 } 726 } 727 jffs2_dbg(1, "Done OK\n"); 728 } else if (jeb == c->gcblock) { 729 jffs2_dbg(2, "Not moving gcblock 0x%08x to dirty_list\n", 730 jeb->offset); 731 } else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) { 732 jffs2_dbg(1, "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n", 733 jeb->offset); 734 list_del(&jeb->list); 735 jffs2_dbg(1, "...and adding to dirty_list\n"); 736 list_add_tail(&jeb->list, &c->dirty_list); 737 } else if (VERYDIRTY(c, jeb->dirty_size) && 738 !VERYDIRTY(c, jeb->dirty_size - addedsize)) { 739 jffs2_dbg(1, "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n", 740 jeb->offset); 741 list_del(&jeb->list); 742 jffs2_dbg(1, "...and adding to very_dirty_list\n"); 743 list_add_tail(&jeb->list, &c->very_dirty_list); 744 } else { 745 jffs2_dbg(1, "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n", 746 jeb->offset, jeb->free_size, jeb->dirty_size, 747 jeb->used_size); 748 } 749 750 spin_unlock(&c->erase_completion_lock); 751 752 if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) || 753 (c->flags & JFFS2_SB_FLAG_BUILDING)) { 754 /* We didn't lock the erase_free_sem */ 755 return; 756 } 757 758 /* The erase_free_sem is locked, and has been since before we marked the node obsolete 759 and potentially put its eraseblock onto the erase_pending_list. Thus, we know that 760 the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet 761 by jffs2_free_jeb_node_refs() in erase.c. Which is nice. */ 762 763 jffs2_dbg(1, "obliterating obsoleted node at 0x%08x\n", 764 ref_offset(ref)); 765 ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n); 766 if (ret) { 767 pr_warn("Read error reading from obsoleted node at 0x%08x: %d\n", 768 ref_offset(ref), ret); 769 goto out_erase_sem; 770 } 771 if (retlen != sizeof(n)) { 772 pr_warn("Short read from obsoleted node at 0x%08x: %zd\n", 773 ref_offset(ref), retlen); 774 goto out_erase_sem; 775 } 776 if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) { 777 pr_warn("Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n", 778 je32_to_cpu(n.totlen), freed_len); 779 goto out_erase_sem; 780 } 781 if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) { 782 jffs2_dbg(1, "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n", 783 ref_offset(ref), je16_to_cpu(n.nodetype)); 784 goto out_erase_sem; 785 } 786 /* XXX FIXME: This is ugly now */ 787 n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE); 788 ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n); 789 if (ret) { 790 pr_warn("Write error in obliterating obsoleted node at 0x%08x: %d\n", 791 ref_offset(ref), ret); 792 goto out_erase_sem; 793 } 794 if (retlen != sizeof(n)) { 795 pr_warn("Short write in obliterating obsoleted node at 0x%08x: %zd\n", 796 ref_offset(ref), retlen); 797 goto out_erase_sem; 798 } 799 800 /* Nodes which have been marked obsolete no longer need to be 801 associated with any inode. Remove them from the per-inode list. 802 803 Note we can't do this for NAND at the moment because we need 804 obsolete dirent nodes to stay on the lists, because of the 805 horridness in jffs2_garbage_collect_deletion_dirent(). Also 806 because we delete the inocache, and on NAND we need that to 807 stay around until all the nodes are actually erased, in order 808 to stop us from giving the same inode number to another newly 809 created inode. */ 810 if (ref->next_in_ino) { 811 struct jffs2_inode_cache *ic; 812 struct jffs2_raw_node_ref **p; 813 814 spin_lock(&c->erase_completion_lock); 815 816 ic = jffs2_raw_ref_to_ic(ref); 817 for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino)) 818 ; 819 820 *p = ref->next_in_ino; 821 ref->next_in_ino = NULL; 822 823 switch (ic->class) { 824 #ifdef CONFIG_JFFS2_FS_XATTR 825 case RAWNODE_CLASS_XATTR_DATUM: 826 jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic); 827 break; 828 case RAWNODE_CLASS_XATTR_REF: 829 jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic); 830 break; 831 #endif 832 default: 833 if (ic->nodes == (void *)ic && ic->pino_nlink == 0) 834 jffs2_del_ino_cache(c, ic); 835 break; 836 } 837 spin_unlock(&c->erase_completion_lock); 838 } 839 840 out_erase_sem: 841 mutex_unlock(&c->erase_free_sem); 842 } 843 844 int jffs2_thread_should_wake(struct jffs2_sb_info *c) 845 { 846 int ret = 0; 847 uint32_t dirty; 848 int nr_very_dirty = 0; 849 struct jffs2_eraseblock *jeb; 850 851 if (!list_empty(&c->erase_complete_list) || 852 !list_empty(&c->erase_pending_list)) 853 return 1; 854 855 if (c->unchecked_size) { 856 jffs2_dbg(1, "jffs2_thread_should_wake(): unchecked_size %d, check_ino #%d\n", 857 c->unchecked_size, c->check_ino); 858 return 1; 859 } 860 861 /* dirty_size contains blocks on erase_pending_list 862 * those blocks are counted in c->nr_erasing_blocks. 863 * If one block is actually erased, it is not longer counted as dirty_space 864 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it 865 * with c->nr_erasing_blocks * c->sector_size again. 866 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks 867 * This helps us to force gc and pick eventually a clean block to spread the load. 868 */ 869 dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size; 870 871 if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger && 872 (dirty > c->nospc_dirty_size)) 873 ret = 1; 874 875 list_for_each_entry(jeb, &c->very_dirty_list, list) { 876 nr_very_dirty++; 877 if (nr_very_dirty == c->vdirty_blocks_gctrigger) { 878 ret = 1; 879 /* In debug mode, actually go through and count them all */ 880 D1(continue); 881 break; 882 } 883 } 884 885 jffs2_dbg(1, "%s(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x, vdirty_blocks %d: %s\n", 886 __func__, c->nr_free_blocks, c->nr_erasing_blocks, 887 c->dirty_size, nr_very_dirty, str_yes_no(ret)); 888 889 return ret; 890 } 891