fs/jffs2/nodemgmt.c

   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: nodemgmt.c,v 1.127 2005/09/20 15:49:12 dedekind Exp $
  11  *
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/compiler.h>
  18 #include <linux/sched.h> /* For cond_resched() */
  19 #include "nodelist.h"
  20 #include "debug.h"
  21
  22 /**
  23  *      jffs2_reserve_space - request physical space to write nodes to flash
  24  *      @c: superblock info
  25  *      @minsize: Minimum acceptable size of allocation
  26  *      @len: Returned value of allocation length
  27  *      @prio: Allocation type - ALLOC_{NORMAL,DELETION}
  28  *
  29  *      Requests a block of physical space on the flash. Returns zero for success
  30  *      and puts 'len' into the appropriate place, or returns -ENOSPC or other
  31  *      error if appropriate. Doesn't return len since that's
  32  *
  33  *      If it returns zero, jffs2_reserve_space() also downs the per-filesystem
  34  *      allocation semaphore, to prevent more than one allocation from being
  35  *      active at any time. The semaphore is later released by jffs2_commit_allocation()
  36  *
  37  *      jffs2_reserve_space() may trigger garbage collection in order to make room
  38  *      for the requested allocation.
  39  */
  40
  41 static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize,
  42                                   uint32_t *len, uint32_t sumsize);
  43
  44 int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
  45                         uint32_t *len, int prio, uint32_t sumsize)
  46 {
  47         int ret = -EAGAIN;
  48         int blocksneeded = c->resv_blocks_write;
  49         /* align it */
  50         minsize = PAD(minsize);
  51
  52         D1(printk(KERN_DEBUG "jffs2_reserve_space(): Requested 0x%x bytes\n", minsize));
  53         down(&c->alloc_sem);
  54
  55         D1(printk(KERN_DEBUG "jffs2_reserve_space(): alloc sem got\n"));
  56
  57         spin_lock(&c->erase_completion_lock);
  58
  59         /* this needs a little more thought (true <tglx> :)) */
  60         while(ret == -EAGAIN) {
  61                 while(c->nr_free_blocks + c->nr_erasing_blocks < blocksneeded) {
  62                         int ret;
  63                         uint32_t dirty, avail;
  64
  65                         /* calculate real dirty size
  66                          * dirty_size contains blocks on erase_pending_list
  67                          * those blocks are counted in c->nr_erasing_blocks.
  68                          * If one block is actually erased, it is not longer counted as dirty_space
  69                          * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
  70                          * with c->nr_erasing_blocks * c->sector_size again.
  71                          * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
  72                          * This helps us to force gc and pick eventually a clean block to spread the load.
  73                          * We add unchecked_size here, as we hopefully will find some space to use.
  74                          * This will affect the sum only once, as gc first finishes checking
  75                          * of nodes.
  76                          */
  77                         dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size + c->unchecked_size;
  78                         if (dirty < c->nospc_dirty_size) {
  79                                 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
  80                                         D1(printk(KERN_NOTICE "jffs2_reserve_space(): Low on dirty space to GC, but it's a deletion. Allowing...\n"));
  81                                         break;
  82                                 }
  83                                 D1(printk(KERN_DEBUG "dirty size 0x%08x + unchecked_size 0x%08x < nospc_dirty_size 0x%08x, returning -ENOSPC\n",
  84                                           dirty, c->unchecked_size, c->sector_size));
  85
  86                                 spin_unlock(&c->erase_completion_lock);
  87                                 up(&c->alloc_sem);
  88                                 return -ENOSPC;
  89                         }
  90
  91                         /* Calc possibly available space. Possibly available means that we
  92                          * don't know, if unchecked size contains obsoleted nodes, which could give us some
  93                          * more usable space. This will affect the sum only once, as gc first finishes checking
  94                          * of nodes.
  95                          + Return -ENOSPC, if the maximum possibly available space is less or equal than
  96                          * blocksneeded * sector_size.
  97                          * This blocks endless gc looping on a filesystem, which is nearly full, even if
  98                          * the check above passes.
  99                          */
 100                         avail = c->free_size + c->dirty_size + c->erasing_size + c->unchecked_size;
 101                         if ( (avail / c->sector_size) <= blocksneeded) {
 102                                 if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
 103                                         D1(printk(KERN_NOTICE "jffs2_reserve_space(): Low on possibly available space, but it's a deletion. Allowing...\n"));
 104                                         break;
 105                                 }
 106
 107                                 D1(printk(KERN_DEBUG "max. available size 0x%08x  < blocksneeded * sector_size 0x%08x, returning -ENOSPC\n",
 108                                           avail, blocksneeded * c->sector_size));
 109                                 spin_unlock(&c->erase_completion_lock);
 110                                 up(&c->alloc_sem);
 111                                 return -ENOSPC;
 112                         }
 113
 114                         up(&c->alloc_sem);
 115
 116                         D1(printk(KERN_DEBUG "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",
 117                                   c->nr_free_blocks, c->nr_erasing_blocks, c->free_size, c->dirty_size, c->wasted_size, c->used_size, c->erasing_size, c->bad_size,
 118                                   c->free_size + c->dirty_size + c->wasted_size + c->used_size + c->erasing_size + c->bad_size, c->flash_size));
 119                         spin_unlock(&c->erase_completion_lock);
 120
 121                         ret = jffs2_garbage_collect_pass(c);
 122                         if (ret)
 123                                 return ret;
 124
 125                         cond_resched();
 126
 127                         if (signal_pending(current))
 128                                 return -EINTR;
 129
 130                         down(&c->alloc_sem);
 131                         spin_lock(&c->erase_completion_lock);
 132                 }
 133
 134                 ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
 135                 if (ret) {
 136                         D1(printk(KERN_DEBUG "jffs2_reserve_space: ret is %d\n", ret));
 137                 }
 138         }
 139         spin_unlock(&c->erase_completion_lock);
 140         if (!ret)
 141                 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
 142         if (ret)
 143                 up(&c->alloc_sem);
 144         return ret;
 145 }
 146
 147 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
 148                            uint32_t *len, uint32_t sumsize)
 149 {
 150         int ret = -EAGAIN;
 151         minsize = PAD(minsize);
 152
 153         D1(printk(KERN_DEBUG "jffs2_reserve_space_gc(): Requested 0x%x bytes\n", minsize));
 154
 155         spin_lock(&c->erase_completion_lock);
 156         while(ret == -EAGAIN) {
 157                 ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
 158                 if (ret) {
 159                         D1(printk(KERN_DEBUG "jffs2_reserve_space_gc: looping, ret is %d\n", ret));
 160                 }
 161         }
 162         spin_unlock(&c->erase_completion_lock);
 163         if (!ret)
 164                 ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
 165
 166         return ret;
 167 }
 168
 169
 170 /* Classify nextblock (clean, dirty of verydirty) and force to select an other one */
 171
 172 static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
 173 {
 174
 175         /* Check, if we have a dirty block now, or if it was dirty already */
 176         if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
 177                 c->dirty_size += jeb->wasted_size;
 178                 c->wasted_size -= jeb->wasted_size;
 179                 jeb->dirty_size += jeb->wasted_size;
 180                 jeb->wasted_size = 0;
 181                 if (VERYDIRTY(c, jeb->dirty_size)) {
 182                         D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
 183                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 184                         list_add_tail(&jeb->list, &c->very_dirty_list);
 185                 } else {
 186                         D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
 187                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 188                         list_add_tail(&jeb->list, &c->dirty_list);
 189                 }
 190         } else {
 191                 D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
 192                   jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 193                 list_add_tail(&jeb->list, &c->clean_list);
 194         }
 195         c->nextblock = NULL;
 196
 197 }
 198
 199 /* Select a new jeb for nextblock */
 200
 201 static int jffs2_find_nextblock(struct jffs2_sb_info *c)
 202 {
 203         struct list_head *next;
 204
 205         /* Take the next block off the 'free' list */
 206
 207         if (list_empty(&c->free_list)) {
 208
 209                 if (!c->nr_erasing_blocks &&
 210                         !list_empty(&c->erasable_list)) {
 211                         struct jffs2_eraseblock *ejeb;
 212
 213                         ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
 214                         list_del(&ejeb->list);
 215                         list_add_tail(&ejeb->list, &c->erase_pending_list);
 216                         c->nr_erasing_blocks++;
 217                         jffs2_erase_pending_trigger(c);
 218                         D1(printk(KERN_DEBUG "jffs2_find_nextblock: Triggering erase of erasable block at 0x%08x\n",
 219                                   ejeb->offset));
 220                 }
 221
 222                 if (!c->nr_erasing_blocks &&
 223                         !list_empty(&c->erasable_pending_wbuf_list)) {
 224                         D1(printk(KERN_DEBUG "jffs2_find_nextblock: Flushing write buffer\n"));
 225                         /* c->nextblock is NULL, no update to c->nextblock allowed */
 226                         spin_unlock(&c->erase_completion_lock);
 227                         jffs2_flush_wbuf_pad(c);
 228                         spin_lock(&c->erase_completion_lock);
 229                         /* Have another go. It'll be on the erasable_list now */
 230                         return -EAGAIN;
 231                 }
 232
 233                 if (!c->nr_erasing_blocks) {
 234                         /* Ouch. We're in GC, or we wouldn't have got here.
 235                            And there's no space left. At all. */
 236                         printk(KERN_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",
 237                                    c->nr_erasing_blocks, c->nr_free_blocks, list_empty(&c->erasable_list)?"yes":"no",
 238                                    list_empty(&c->erasing_list)?"yes":"no", list_empty(&c->erase_pending_list)?"yes":"no");
 239                         return -ENOSPC;
 240                 }
 241
 242                 spin_unlock(&c->erase_completion_lock);
 243                 /* Don't wait for it; just erase one right now */
 244                 jffs2_erase_pending_blocks(c, 1);
 245                 spin_lock(&c->erase_completion_lock);
 246
 247                 /* An erase may have failed, decreasing the
 248                    amount of free space available. So we must
 249                    restart from the beginning */
 250                 return -EAGAIN;
 251         }
 252
 253         next = c->free_list.next;
 254         list_del(next);
 255         c->nextblock = list_entry(next, struct jffs2_eraseblock, list);
 256         c->nr_free_blocks--;
 257
 258         jffs2_sum_reset_collected(c->summary); /* reset collected summary */
 259
 260         D1(printk(KERN_DEBUG "jffs2_find_nextblock(): new nextblock = 0x%08x\n", c->nextblock->offset));
 261
 262         return 0;
 263 }
 264
 265 /* Called with alloc sem _and_ erase_completion_lock */
 266 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 267                                   uint32_t *len, uint32_t sumsize)
 268 {
 269         struct jffs2_eraseblock *jeb = c->nextblock;
 270         uint32_t reserved_size;                         /* for summary information at the end of the jeb */
 271         int ret;
 272
 273  restart:
 274         reserved_size = 0;
 275
 276         if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) {
 277                                                         /* NOSUM_SIZE means not to generate summary */
 278
 279                 if (jeb) {
 280                         reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
 281                         dbg_summary("minsize=%d , jeb->free=%d ,"
 282                                                 "summary->size=%d , sumsize=%d\n",
 283                                                 minsize, jeb->free_size,
 284                                                 c->summary->sum_size, sumsize);
 285                 }
 286
 287                 /* Is there enough space for writing out the current node, or we have to
 288                    write out summary information now, close this jeb and select new nextblock? */
 289                 if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize +
 290                                         JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) {
 291
 292                         /* Has summary been disabled for this jeb? */
 293                         if (jffs2_sum_is_disabled(c->summary)) {
 294                                 sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
 295                                 goto restart;
 296                         }
 297
 298                         /* Writing out the collected summary information */
 299                         dbg_summary("generating summary for 0x%08x.\n", jeb->offset);
 300                         ret = jffs2_sum_write_sumnode(c);
 301
 302                         if (ret)
 303                                 return ret;
 304
 305                         if (jffs2_sum_is_disabled(c->summary)) {
 306                                 /* jffs2_write_sumnode() couldn't write out the summary information
 307                                    diabling summary for this jeb and free the collected information
 308                                  */
 309                                 sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
 310                                 goto restart;
 311                         }
 312
 313                         jffs2_close_nextblock(c, jeb);
 314                         jeb = NULL;
 315                         /* keep always valid value in reserved_size */
 316                         reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
 317                 }
 318         } else {
 319                 if (jeb && minsize > jeb->free_size) {
 320                         /* Skip the end of this block and file it as having some dirty space */
 321                         /* If there's a pending write to it, flush now */
 322
 323                         if (jffs2_wbuf_dirty(c)) {
 324                                 spin_unlock(&c->erase_completion_lock);
 325                                 D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));
 326                                 jffs2_flush_wbuf_pad(c);
 327                                 spin_lock(&c->erase_completion_lock);
 328                                 jeb = c->nextblock;
 329                                 goto restart;
 330                         }
 331
 332                         c->wasted_size += jeb->free_size;
 333                         c->free_size -= jeb->free_size;
 334                         jeb->wasted_size += jeb->free_size;
 335                         jeb->free_size = 0;
 336
 337                         jffs2_close_nextblock(c, jeb);
 338                         jeb = NULL;
 339                 }
 340         }
 341
 342         if (!jeb) {
 343
 344                 ret = jffs2_find_nextblock(c);
 345                 if (ret)
 346                         return ret;
 347
 348                 jeb = c->nextblock;
 349
 350                 if (jeb->free_size != c->sector_size - c->cleanmarker_size) {
 351                         printk(KERN_WARNING "Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", jeb->offset, jeb->free_size);
 352                         goto restart;
 353                 }
 354         }
 355         /* OK, jeb (==c->nextblock) is now pointing at a block which definitely has
 356            enough space */
 357         *len = jeb->free_size - reserved_size;
 358
 359         if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size &&
 360             !jeb->first_node->next_in_ino) {
 361                 /* Only node in it beforehand was a CLEANMARKER node (we think).
 362                    So mark it obsolete now that there's going to be another node
 363                    in the block. This will reduce used_size to zero but We've
 364                    already set c->nextblock so that jffs2_mark_node_obsolete()
 365                    won't try to refile it to the dirty_list.
 366                 */
 367                 spin_unlock(&c->erase_completion_lock);
 368                 jffs2_mark_node_obsolete(c, jeb->first_node);
 369                 spin_lock(&c->erase_completion_lock);
 370         }
 371
 372         D1(printk(KERN_DEBUG "jffs2_do_reserve_space(): Giving 0x%x bytes at 0x%x\n",
 373                   *len, jeb->offset + (c->sector_size - jeb->free_size)));
 374         return 0;
 375 }
 376
 377 /**
 378  *      jffs2_add_physical_node_ref - add a physical node reference to the list
 379  *      @c: superblock info
 380  *      @new: new node reference to add
 381  *      @len: length of this physical node
 382  *
 383  *      Should only be used to report nodes for which space has been allocated
 384  *      by jffs2_reserve_space.
 385  *
 386  *      Must be called with the alloc_sem held.
 387  */
 388
 389 struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
 390                                                        uint32_t ofs, uint32_t len,
 391                                                        struct jffs2_inode_cache *ic)
 392 {
 393         struct jffs2_eraseblock *jeb;
 394         struct jffs2_raw_node_ref *new;
 395
 396         jeb = &c->blocks[ofs / c->sector_size];
 397
 398         D1(printk(KERN_DEBUG "jffs2_add_physical_node_ref(): Node at 0x%x(%d), size 0x%x\n",
 399                   ofs & ~3, ofs & 3, len));
 400 #if 1
 401         /* Allow non-obsolete nodes only to be added at the end of c->nextblock,
 402            if c->nextblock is set. Note that wbuf.c will file obsolete nodes
 403            even after refiling c->nextblock */
 404         if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE))
 405             && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) {
 406                 printk(KERN_WARNING "argh. node added in wrong place\n");
 407                 return ERR_PTR(-EINVAL);
 408         }
 409 #endif
 410         spin_lock(&c->erase_completion_lock);
 411
 412         new = jffs2_link_node_ref(c, jeb, ofs, len, ic);
 413
 414         if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) {
 415                 /* If it lives on the dirty_list, jffs2_reserve_space will put it there */
 416                 D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
 417                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 418                 if (jffs2_wbuf_dirty(c)) {
 419                         /* Flush the last write in the block if it's outstanding */
 420                         spin_unlock(&c->erase_completion_lock);
 421                         jffs2_flush_wbuf_pad(c);
 422                         spin_lock(&c->erase_completion_lock);
 423                 }
 424
 425                 list_add_tail(&jeb->list, &c->clean_list);
 426                 c->nextblock = NULL;
 427         }
 428         jffs2_dbg_acct_sanity_check_nolock(c,jeb);
 429         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
 430
 431         spin_unlock(&c->erase_completion_lock);
 432
 433         return new;
 434 }
 435
 436
 437 void jffs2_complete_reservation(struct jffs2_sb_info *c)
 438 {
 439         D1(printk(KERN_DEBUG "jffs2_complete_reservation()\n"));
 440         jffs2_garbage_collect_trigger(c);
 441         up(&c->alloc_sem);
 442 }
 443
 444 static inline int on_list(struct list_head *obj, struct list_head *head)
 445 {
 446         struct list_head *this;
 447
 448         list_for_each(this, head) {
 449                 if (this == obj) {
 450                         D1(printk("%p is on list at %p\n", obj, head));
 451                         return 1;
 452
 453                 }
 454         }
 455         return 0;
 456 }
 457
 458 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref)
 459 {
 460         struct jffs2_eraseblock *jeb;
 461         struct jffs2_raw_node_ref *next_ref;
 462         int blocknr;
 463         struct jffs2_unknown_node n;
 464         int ret, addedsize;
 465         size_t retlen;
 466         uint32_t freed_len;
 467
 468         if(!ref) {
 469                 printk(KERN_NOTICE "EEEEEK. jffs2_mark_node_obsolete called with NULL node\n");
 470                 return;
 471         }
 472         if (ref_obsolete(ref)) {
 473                 D1(printk(KERN_DEBUG "jffs2_mark_node_obsolete called with already obsolete node at 0x%08x\n", ref_offset(ref)));
 474                 return;
 475         }
 476         blocknr = ref->flash_offset / c->sector_size;
 477         if (blocknr >= c->nr_blocks) {
 478                 printk(KERN_NOTICE "raw node at 0x%08x is off the end of device!\n", ref->flash_offset);
 479                 BUG();
 480         }
 481         jeb = &c->blocks[blocknr];
 482
 483         if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) &&
 484             !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) {
 485                 /* Hm. This may confuse static lock analysis. If any of the above
 486                    three conditions is false, we're going to return from this
 487                    function without actually obliterating any nodes or freeing
 488                    any jffs2_raw_node_refs. So we don't need to stop erases from
 489                    happening, or protect against people holding an obsolete
 490                    jffs2_raw_node_ref without the erase_completion_lock. */
 491                 down(&c->erase_free_sem);
 492         }
 493
 494         spin_lock(&c->erase_completion_lock);
 495
 496         freed_len = ref_totlen(c, jeb, ref);
 497
 498         if (ref_flags(ref) == REF_UNCHECKED) {
 499                 D1(if (unlikely(jeb->unchecked_size < freed_len)) {
 500                         printk(KERN_NOTICE "raw unchecked node of size 0x%08x freed from erase block %d at 0x%08x, but unchecked_size was already 0x%08x\n",
 501                                freed_len, blocknr, ref->flash_offset, jeb->used_size);
 502                         BUG();
 503                 })
 504                 D1(printk(KERN_DEBUG "Obsoleting previously unchecked node at 0x%08x of len %x: ", ref_offset(ref), freed_len));
 505                 jeb->unchecked_size -= freed_len;
 506                 c->unchecked_size -= freed_len;
 507         } else {
 508                 D1(if (unlikely(jeb->used_size < freed_len)) {
 509                         printk(KERN_NOTICE "raw node of size 0x%08x freed from erase block %d at 0x%08x, but used_size was already 0x%08x\n",
 510                                freed_len, blocknr, ref->flash_offset, jeb->used_size);
 511                         BUG();
 512                 })
 513                 D1(printk(KERN_DEBUG "Obsoleting node at 0x%08x of len %#x: ", ref_offset(ref), freed_len));
 514                 jeb->used_size -= freed_len;
 515                 c->used_size -= freed_len;
 516         }
 517
 518         // Take care, that wasted size is taken into concern
 519         if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) {
 520                 D1(printk("Dirtying\n"));
 521                 addedsize = freed_len;
 522                 jeb->dirty_size += freed_len;
 523                 c->dirty_size += freed_len;
 524
 525                 /* Convert wasted space to dirty, if not a bad block */
 526                 if (jeb->wasted_size) {
 527                         if (on_list(&jeb->list, &c->bad_used_list)) {
 528                                 D1(printk(KERN_DEBUG "Leaving block at %08x on the bad_used_list\n",
 529                                           jeb->offset));
 530                                 addedsize = 0; /* To fool the refiling code later */
 531                         } else {
 532                                 D1(printk(KERN_DEBUG "Converting %d bytes of wasted space to dirty in block at %08x\n",
 533                                           jeb->wasted_size, jeb->offset));
 534                                 addedsize += jeb->wasted_size;
 535                                 jeb->dirty_size += jeb->wasted_size;
 536                                 c->dirty_size += jeb->wasted_size;
 537                                 c->wasted_size -= jeb->wasted_size;
 538                                 jeb->wasted_size = 0;
 539                         }
 540                 }
 541         } else {
 542                 D1(printk("Wasting\n"));
 543                 addedsize = 0;
 544                 jeb->wasted_size += freed_len;
 545                 c->wasted_size += freed_len;
 546         }
 547         ref->flash_offset = ref_offset(ref) | REF_OBSOLETE;
 548
 549         jffs2_dbg_acct_sanity_check_nolock(c, jeb);
 550         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
 551
 552         if (c->flags & JFFS2_SB_FLAG_SCANNING) {
 553                 /* Flash scanning is in progress. Don't muck about with the block
 554                    lists because they're not ready yet, and don't actually
 555                    obliterate nodes that look obsolete. If they weren't
 556                    marked obsolete on the flash at the time they _became_
 557                    obsolete, there was probably a reason for that. */
 558                 spin_unlock(&c->erase_completion_lock);
 559                 /* We didn't lock the erase_free_sem */
 560                 return;
 561         }
 562
 563         if (jeb == c->nextblock) {
 564                 D2(printk(KERN_DEBUG "Not moving nextblock 0x%08x to dirty/erase_pending list\n", jeb->offset));
 565         } else if (!jeb->used_size && !jeb->unchecked_size) {
 566                 if (jeb == c->gcblock) {
 567                         D1(printk(KERN_DEBUG "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n", jeb->offset));
 568                         c->gcblock = NULL;
 569                 } else {
 570                         D1(printk(KERN_DEBUG "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n", jeb->offset));
 571                         list_del(&jeb->list);
 572                 }
 573                 if (jffs2_wbuf_dirty(c)) {
 574                         D1(printk(KERN_DEBUG "...and adding to erasable_pending_wbuf_list\n"));
 575                         list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list);
 576                 } else {
 577                         if (jiffies & 127) {
 578                                 /* Most of the time, we just erase it immediately. Otherwise we
 579                                    spend ages scanning it on mount, etc. */
 580                                 D1(printk(KERN_DEBUG "...and adding to erase_pending_list\n"));
 581                                 list_add_tail(&jeb->list, &c->erase_pending_list);
 582                                 c->nr_erasing_blocks++;
 583                                 jffs2_erase_pending_trigger(c);
 584                         } else {
 585                                 /* Sometimes, however, we leave it elsewhere so it doesn't get
 586                                    immediately reused, and we spread the load a bit. */
 587                                 D1(printk(KERN_DEBUG "...and adding to erasable_list\n"));
 588                                 list_add_tail(&jeb->list, &c->erasable_list);
 589                         }
 590                 }
 591                 D1(printk(KERN_DEBUG "Done OK\n"));
 592         } else if (jeb == c->gcblock) {
 593                 D2(printk(KERN_DEBUG "Not moving gcblock 0x%08x to dirty_list\n", jeb->offset));
 594         } else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) {
 595                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n", jeb->offset));
 596                 list_del(&jeb->list);
 597                 D1(printk(KERN_DEBUG "...and adding to dirty_list\n"));
 598                 list_add_tail(&jeb->list, &c->dirty_list);
 599         } else if (VERYDIRTY(c, jeb->dirty_size) &&
 600                    !VERYDIRTY(c, jeb->dirty_size - addedsize)) {
 601                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n", jeb->offset));
 602                 list_del(&jeb->list);
 603                 D1(printk(KERN_DEBUG "...and adding to very_dirty_list\n"));
 604                 list_add_tail(&jeb->list, &c->very_dirty_list);
 605         } else {
 606                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n",
 607                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 608         }
 609
 610         spin_unlock(&c->erase_completion_lock);
 611
 612         if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) ||
 613                 (c->flags & JFFS2_SB_FLAG_BUILDING)) {
 614                 /* We didn't lock the erase_free_sem */
 615                 return;
 616         }
 617
 618         /* The erase_free_sem is locked, and has been since before we marked the node obsolete
 619            and potentially put its eraseblock onto the erase_pending_list. Thus, we know that
 620            the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet
 621            by jffs2_free_jeb_node_refs() in erase.c. Which is nice. */
 622
 623         D1(printk(KERN_DEBUG "obliterating obsoleted node at 0x%08x\n", ref_offset(ref)));
 624         ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
 625         if (ret) {
 626                 printk(KERN_WARNING "Read error reading from obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
 627                 goto out_erase_sem;
 628         }
 629         if (retlen != sizeof(n)) {
 630                 printk(KERN_WARNING "Short read from obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
 631                 goto out_erase_sem;
 632         }
 633         if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) {
 634                 printk(KERN_WARNING "Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n", je32_to_cpu(n.totlen), freed_len);
 635                 goto out_erase_sem;
 636         }
 637         if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) {
 638                 D1(printk(KERN_DEBUG "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n", ref_offset(ref), je16_to_cpu(n.nodetype)));
 639                 goto out_erase_sem;
 640         }
 641         /* XXX FIXME: This is ugly now */
 642         n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE);
 643         ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
 644         if (ret) {
 645                 printk(KERN_WARNING "Write error in obliterating obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
 646                 goto out_erase_sem;
 647         }
 648         if (retlen != sizeof(n)) {
 649                 printk(KERN_WARNING "Short write in obliterating obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
 650                 goto out_erase_sem;
 651         }
 652
 653         /* Nodes which have been marked obsolete no longer need to be
 654            associated with any inode. Remove them from the per-inode list.
 655
 656            Note we can't do this for NAND at the moment because we need
 657            obsolete dirent nodes to stay on the lists, because of the
 658            horridness in jffs2_garbage_collect_deletion_dirent(). Also
 659            because we delete the inocache, and on NAND we need that to
 660            stay around until all the nodes are actually erased, in order
 661            to stop us from giving the same inode number to another newly
 662            created inode. */
 663         if (ref->next_in_ino) {
 664                 struct jffs2_inode_cache *ic;
 665                 struct jffs2_raw_node_ref **p;
 666
 667                 spin_lock(&c->erase_completion_lock);
 668
 669                 ic = jffs2_raw_ref_to_ic(ref);
 670                 /* It seems we should never call jffs2_mark_node_obsolete() for
 671                    XATTR nodes.... yet. Make sure we notice if/when we change
 672                    that :) */
 673                 BUG_ON(ic->class != RAWNODE_CLASS_INODE_CACHE);
 674                 for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino))
 675                         ;
 676
 677                 *p = ref->next_in_ino;
 678                 ref->next_in_ino = NULL;
 679
 680                 if (ic->nodes == (void *)ic && ic->nlink == 0)
 681                         jffs2_del_ino_cache(c, ic);
 682
 683                 spin_unlock(&c->erase_completion_lock);
 684         }
 685
 686
 687         /* Merge with the next node in the physical list, if there is one
 688            and if it's also obsolete and if it doesn't belong to any inode */
 689         next_ref = ref_next(ref);
 690
 691         if (next_ref && ref_obsolete(next_ref) && !next_ref->next_in_ino) {
 692                 spin_lock(&c->erase_completion_lock);
 693
 694 #ifdef TEST_TOTLEN
 695                 ref->__totlen += next_ref->__totlen;
 696 #endif
 697                 ref->next_phys = ref_next(next_ref);
 698                 if (jeb->last_node == next_ref) jeb->last_node = ref;
 699                 if (jeb->gc_node == next_ref) {
 700                         /* gc will be happy continuing gc on this node */
 701                         jeb->gc_node=ref;
 702                 }
 703                 spin_unlock(&c->erase_completion_lock);
 704
 705                 __jffs2_free_raw_node_ref(next_ref);
 706         }
 707
 708         /* Also merge with the previous node in the list, if there is one
 709            and that one is obsolete */
 710         if (ref != jeb->first_node ) {
 711                 struct jffs2_raw_node_ref *p = jeb->first_node;
 712
 713                 spin_lock(&c->erase_completion_lock);
 714
 715                 while ((next_ref = ref_next(ref)) != ref)
 716                         p = next_ref;
 717
 718                 if (ref_obsolete(p) && !ref->next_in_ino) {
 719 #ifdef TEST_TOTLEN
 720                         p->__totlen += ref->__totlen;
 721 #endif
 722                         if (jeb->last_node == ref) {
 723                                 jeb->last_node = p;
 724                         }
 725                         if (jeb->gc_node == ref) {
 726                                 /* gc will be happy continuing gc on this node */
 727                                 jeb->gc_node=p;
 728                         }
 729                         p->next_phys = ref_next(ref);
 730                         __jffs2_free_raw_node_ref(ref);
 731                 }
 732                 spin_unlock(&c->erase_completion_lock);
 733         }
 734  out_erase_sem:
 735         up(&c->erase_free_sem);
 736 }
 737
 738 int jffs2_thread_should_wake(struct jffs2_sb_info *c)
 739 {
 740         int ret = 0;
 741         uint32_t dirty;
 742
 743         if (c->unchecked_size) {
 744                 D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): unchecked_size %d, checked_ino #%d\n",
 745                           c->unchecked_size, c->checked_ino));
 746                 return 1;
 747         }
 748
 749         /* dirty_size contains blocks on erase_pending_list
 750          * those blocks are counted in c->nr_erasing_blocks.
 751          * If one block is actually erased, it is not longer counted as dirty_space
 752          * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
 753          * with c->nr_erasing_blocks * c->sector_size again.
 754          * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
 755          * This helps us to force gc and pick eventually a clean block to spread the load.
 756          */
 757         dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size;
 758
 759         if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger &&
 760                         (dirty > c->nospc_dirty_size))
 761                 ret = 1;
 762
 763         D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x: %s\n",
 764                   c->nr_free_blocks, c->nr_erasing_blocks, c->dirty_size, ret?"yes":"no"));
 765
 766         return ret;
 767 }