[JFFS2] Remove flash offset argument from various functions.
[linux-2.6] / 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                 up(&c->alloc_sem);
142         return ret;
143 }
144
145 int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
146                            uint32_t *len, uint32_t sumsize)
147 {
148         int ret = -EAGAIN;
149         minsize = PAD(minsize);
150
151         D1(printk(KERN_DEBUG "jffs2_reserve_space_gc(): Requested 0x%x bytes\n", minsize));
152
153         spin_lock(&c->erase_completion_lock);
154         while(ret == -EAGAIN) {
155                 ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
156                 if (ret) {
157                         D1(printk(KERN_DEBUG "jffs2_reserve_space_gc: looping, ret is %d\n", ret));
158                 }
159         }
160         spin_unlock(&c->erase_completion_lock);
161         return ret;
162 }
163
164
165 /* Classify nextblock (clean, dirty of verydirty) and force to select an other one */
166
167 static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
168 {
169
170         /* Check, if we have a dirty block now, or if it was dirty already */
171         if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
172                 c->dirty_size += jeb->wasted_size;
173                 c->wasted_size -= jeb->wasted_size;
174                 jeb->dirty_size += jeb->wasted_size;
175                 jeb->wasted_size = 0;
176                 if (VERYDIRTY(c, jeb->dirty_size)) {
177                         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",
178                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
179                         list_add_tail(&jeb->list, &c->very_dirty_list);
180                 } else {
181                         D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
182                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
183                         list_add_tail(&jeb->list, &c->dirty_list);
184                 }
185         } else {
186                 D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_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->clean_list);
189         }
190         c->nextblock = NULL;
191
192 }
193
194 /* Select a new jeb for nextblock */
195
196 static int jffs2_find_nextblock(struct jffs2_sb_info *c)
197 {
198         struct list_head *next;
199
200         /* Take the next block off the 'free' list */
201
202         if (list_empty(&c->free_list)) {
203
204                 if (!c->nr_erasing_blocks &&
205                         !list_empty(&c->erasable_list)) {
206                         struct jffs2_eraseblock *ejeb;
207
208                         ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
209                         list_del(&ejeb->list);
210                         list_add_tail(&ejeb->list, &c->erase_pending_list);
211                         c->nr_erasing_blocks++;
212                         jffs2_erase_pending_trigger(c);
213                         D1(printk(KERN_DEBUG "jffs2_find_nextblock: Triggering erase of erasable block at 0x%08x\n",
214                                   ejeb->offset));
215                 }
216
217                 if (!c->nr_erasing_blocks &&
218                         !list_empty(&c->erasable_pending_wbuf_list)) {
219                         D1(printk(KERN_DEBUG "jffs2_find_nextblock: Flushing write buffer\n"));
220                         /* c->nextblock is NULL, no update to c->nextblock allowed */
221                         spin_unlock(&c->erase_completion_lock);
222                         jffs2_flush_wbuf_pad(c);
223                         spin_lock(&c->erase_completion_lock);
224                         /* Have another go. It'll be on the erasable_list now */
225                         return -EAGAIN;
226                 }
227
228                 if (!c->nr_erasing_blocks) {
229                         /* Ouch. We're in GC, or we wouldn't have got here.
230                            And there's no space left. At all. */
231                         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",
232                                    c->nr_erasing_blocks, c->nr_free_blocks, list_empty(&c->erasable_list)?"yes":"no",
233                                    list_empty(&c->erasing_list)?"yes":"no", list_empty(&c->erase_pending_list)?"yes":"no");
234                         return -ENOSPC;
235                 }
236
237                 spin_unlock(&c->erase_completion_lock);
238                 /* Don't wait for it; just erase one right now */
239                 jffs2_erase_pending_blocks(c, 1);
240                 spin_lock(&c->erase_completion_lock);
241
242                 /* An erase may have failed, decreasing the
243                    amount of free space available. So we must
244                    restart from the beginning */
245                 return -EAGAIN;
246         }
247
248         next = c->free_list.next;
249         list_del(next);
250         c->nextblock = list_entry(next, struct jffs2_eraseblock, list);
251         c->nr_free_blocks--;
252
253         jffs2_sum_reset_collected(c->summary); /* reset collected summary */
254
255         D1(printk(KERN_DEBUG "jffs2_find_nextblock(): new nextblock = 0x%08x\n", c->nextblock->offset));
256
257         return 0;
258 }
259
260 /* Called with alloc sem _and_ erase_completion_lock */
261 static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
262                                   uint32_t *len, uint32_t sumsize)
263 {
264         struct jffs2_eraseblock *jeb = c->nextblock;
265         uint32_t reserved_size;                         /* for summary information at the end of the jeb */
266         int ret;
267
268  restart:
269         reserved_size = 0;
270
271         if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) {
272                                                         /* NOSUM_SIZE means not to generate summary */
273
274                 if (jeb) {
275                         reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
276                         dbg_summary("minsize=%d , jeb->free=%d ,"
277                                                 "summary->size=%d , sumsize=%d\n",
278                                                 minsize, jeb->free_size,
279                                                 c->summary->sum_size, sumsize);
280                 }
281
282                 /* Is there enough space for writing out the current node, or we have to
283                    write out summary information now, close this jeb and select new nextblock? */
284                 if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize +
285                                         JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) {
286
287                         /* Has summary been disabled for this jeb? */
288                         if (jffs2_sum_is_disabled(c->summary)) {
289                                 sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
290                                 goto restart;
291                         }
292
293                         /* Writing out the collected summary information */
294                         dbg_summary("generating summary for 0x%08x.\n", jeb->offset);
295                         ret = jffs2_sum_write_sumnode(c);
296
297                         if (ret)
298                                 return ret;
299
300                         if (jffs2_sum_is_disabled(c->summary)) {
301                                 /* jffs2_write_sumnode() couldn't write out the summary information
302                                    diabling summary for this jeb and free the collected information
303                                  */
304                                 sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
305                                 goto restart;
306                         }
307
308                         jffs2_close_nextblock(c, jeb);
309                         jeb = NULL;
310                         /* keep always valid value in reserved_size */
311                         reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
312                 }
313         } else {
314                 if (jeb && minsize > jeb->free_size) {
315                         /* Skip the end of this block and file it as having some dirty space */
316                         /* If there's a pending write to it, flush now */
317
318                         if (jffs2_wbuf_dirty(c)) {
319                                 spin_unlock(&c->erase_completion_lock);
320                                 D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));
321                                 jffs2_flush_wbuf_pad(c);
322                                 spin_lock(&c->erase_completion_lock);
323                                 jeb = c->nextblock;
324                                 goto restart;
325                         }
326
327                         c->wasted_size += jeb->free_size;
328                         c->free_size -= jeb->free_size;
329                         jeb->wasted_size += jeb->free_size;
330                         jeb->free_size = 0;
331
332                         jffs2_close_nextblock(c, jeb);
333                         jeb = NULL;
334                 }
335         }
336
337         if (!jeb) {
338
339                 ret = jffs2_find_nextblock(c);
340                 if (ret)
341                         return ret;
342
343                 jeb = c->nextblock;
344
345                 if (jeb->free_size != c->sector_size - c->cleanmarker_size) {
346                         printk(KERN_WARNING "Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", jeb->offset, jeb->free_size);
347                         goto restart;
348                 }
349         }
350         /* OK, jeb (==c->nextblock) is now pointing at a block which definitely has
351            enough space */
352         *len = jeb->free_size - reserved_size;
353
354         if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size &&
355             !jeb->first_node->next_in_ino) {
356                 /* Only node in it beforehand was a CLEANMARKER node (we think).
357                    So mark it obsolete now that there's going to be another node
358                    in the block. This will reduce used_size to zero but We've
359                    already set c->nextblock so that jffs2_mark_node_obsolete()
360                    won't try to refile it to the dirty_list.
361                 */
362                 spin_unlock(&c->erase_completion_lock);
363                 jffs2_mark_node_obsolete(c, jeb->first_node);
364                 spin_lock(&c->erase_completion_lock);
365         }
366
367         D1(printk(KERN_DEBUG "jffs2_do_reserve_space(): Giving 0x%x bytes at 0x%x\n",
368                   *len, jeb->offset + (c->sector_size - jeb->free_size)));
369         return 0;
370 }
371
372 /**
373  *      jffs2_add_physical_node_ref - add a physical node reference to the list
374  *      @c: superblock info
375  *      @new: new node reference to add
376  *      @len: length of this physical node
377  *
378  *      Should only be used to report nodes for which space has been allocated
379  *      by jffs2_reserve_space.
380  *
381  *      Must be called with the alloc_sem held.
382  */
383
384 int jffs2_add_physical_node_ref(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *new,
385                                 uint32_t len, struct jffs2_inode_cache *ic)
386 {
387         struct jffs2_eraseblock *jeb;
388
389         jeb = &c->blocks[new->flash_offset / c->sector_size];
390 #ifdef TEST_TOTLEN
391         new->__totlen = len;
392 #endif
393
394         D1(printk(KERN_DEBUG "jffs2_add_physical_node_ref(): Node at 0x%x(%d), size 0x%x\n", ref_offset(new), ref_flags(new), len));
395 #if 1
396         /* we could get some obsolete nodes after nextblock was refiled
397            in wbuf.c */
398         if ((c->nextblock || !ref_obsolete(new))
399             &&(jeb != c->nextblock || ref_offset(new) != jeb->offset + (c->sector_size - jeb->free_size))) {
400                 printk(KERN_WARNING "argh. node added in wrong place\n");
401                 jffs2_free_raw_node_ref(new);
402                 return -EINVAL;
403         }
404 #endif
405         spin_lock(&c->erase_completion_lock);
406
407         jffs2_link_node_ref(c, jeb, new, len, ic);
408
409         if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) {
410                 /* If it lives on the dirty_list, jffs2_reserve_space will put it there */
411                 D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
412                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
413                 if (jffs2_wbuf_dirty(c)) {
414                         /* Flush the last write in the block if it's outstanding */
415                         spin_unlock(&c->erase_completion_lock);
416                         jffs2_flush_wbuf_pad(c);
417                         spin_lock(&c->erase_completion_lock);
418                 }
419
420                 list_add_tail(&jeb->list, &c->clean_list);
421                 c->nextblock = NULL;
422         }
423         jffs2_dbg_acct_sanity_check_nolock(c,jeb);
424         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
425
426         spin_unlock(&c->erase_completion_lock);
427
428         return 0;
429 }
430
431
432 void jffs2_complete_reservation(struct jffs2_sb_info *c)
433 {
434         D1(printk(KERN_DEBUG "jffs2_complete_reservation()\n"));
435         jffs2_garbage_collect_trigger(c);
436         up(&c->alloc_sem);
437 }
438
439 static inline int on_list(struct list_head *obj, struct list_head *head)
440 {
441         struct list_head *this;
442
443         list_for_each(this, head) {
444                 if (this == obj) {
445                         D1(printk("%p is on list at %p\n", obj, head));
446                         return 1;
447
448                 }
449         }
450         return 0;
451 }
452
453 void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref)
454 {
455         struct jffs2_eraseblock *jeb;
456         int blocknr;
457         struct jffs2_unknown_node n;
458         int ret, addedsize;
459         size_t retlen;
460         uint32_t freed_len;
461
462         if(!ref) {
463                 printk(KERN_NOTICE "EEEEEK. jffs2_mark_node_obsolete called with NULL node\n");
464                 return;
465         }
466         if (ref_obsolete(ref)) {
467                 D1(printk(KERN_DEBUG "jffs2_mark_node_obsolete called with already obsolete node at 0x%08x\n", ref_offset(ref)));
468                 return;
469         }
470         blocknr = ref->flash_offset / c->sector_size;
471         if (blocknr >= c->nr_blocks) {
472                 printk(KERN_NOTICE "raw node at 0x%08x is off the end of device!\n", ref->flash_offset);
473                 BUG();
474         }
475         jeb = &c->blocks[blocknr];
476
477         if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) &&
478             !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) {
479                 /* Hm. This may confuse static lock analysis. If any of the above
480                    three conditions is false, we're going to return from this
481                    function without actually obliterating any nodes or freeing
482                    any jffs2_raw_node_refs. So we don't need to stop erases from
483                    happening, or protect against people holding an obsolete
484                    jffs2_raw_node_ref without the erase_completion_lock. */
485                 down(&c->erase_free_sem);
486         }
487
488         spin_lock(&c->erase_completion_lock);
489
490         freed_len = ref_totlen(c, jeb, ref);
491
492         if (ref_flags(ref) == REF_UNCHECKED) {
493                 D1(if (unlikely(jeb->unchecked_size < freed_len)) {
494                         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",
495                                freed_len, blocknr, ref->flash_offset, jeb->used_size);
496                         BUG();
497                 })
498                 D1(printk(KERN_DEBUG "Obsoleting previously unchecked node at 0x%08x of len %x: ", ref_offset(ref), freed_len));
499                 jeb->unchecked_size -= freed_len;
500                 c->unchecked_size -= freed_len;
501         } else {
502                 D1(if (unlikely(jeb->used_size < freed_len)) {
503                         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",
504                                freed_len, blocknr, ref->flash_offset, jeb->used_size);
505                         BUG();
506                 })
507                 D1(printk(KERN_DEBUG "Obsoleting node at 0x%08x of len %#x: ", ref_offset(ref), freed_len));
508                 jeb->used_size -= freed_len;
509                 c->used_size -= freed_len;
510         }
511
512         // Take care, that wasted size is taken into concern
513         if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) {
514                 D1(printk(KERN_DEBUG "Dirtying\n"));
515                 addedsize = freed_len;
516                 jeb->dirty_size += freed_len;
517                 c->dirty_size += freed_len;
518
519                 /* Convert wasted space to dirty, if not a bad block */
520                 if (jeb->wasted_size) {
521                         if (on_list(&jeb->list, &c->bad_used_list)) {
522                                 D1(printk(KERN_DEBUG "Leaving block at %08x on the bad_used_list\n",
523                                           jeb->offset));
524                                 addedsize = 0; /* To fool the refiling code later */
525                         } else {
526                                 D1(printk(KERN_DEBUG "Converting %d bytes of wasted space to dirty in block at %08x\n",
527                                           jeb->wasted_size, jeb->offset));
528                                 addedsize += jeb->wasted_size;
529                                 jeb->dirty_size += jeb->wasted_size;
530                                 c->dirty_size += jeb->wasted_size;
531                                 c->wasted_size -= jeb->wasted_size;
532                                 jeb->wasted_size = 0;
533                         }
534                 }
535         } else {
536                 D1(printk(KERN_DEBUG "Wasting\n"));
537                 addedsize = 0;
538                 jeb->wasted_size += freed_len;
539                 c->wasted_size += freed_len;
540         }
541         ref->flash_offset = ref_offset(ref) | REF_OBSOLETE;
542
543         jffs2_dbg_acct_sanity_check_nolock(c, jeb);
544         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
545
546         if (c->flags & JFFS2_SB_FLAG_SCANNING) {
547                 /* Flash scanning is in progress. Don't muck about with the block
548                    lists because they're not ready yet, and don't actually
549                    obliterate nodes that look obsolete. If they weren't
550                    marked obsolete on the flash at the time they _became_
551                    obsolete, there was probably a reason for that. */
552                 spin_unlock(&c->erase_completion_lock);
553                 /* We didn't lock the erase_free_sem */
554                 return;
555         }
556
557         if (jeb == c->nextblock) {
558                 D2(printk(KERN_DEBUG "Not moving nextblock 0x%08x to dirty/erase_pending list\n", jeb->offset));
559         } else if (!jeb->used_size && !jeb->unchecked_size) {
560                 if (jeb == c->gcblock) {
561                         D1(printk(KERN_DEBUG "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n", jeb->offset));
562                         c->gcblock = NULL;
563                 } else {
564                         D1(printk(KERN_DEBUG "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n", jeb->offset));
565                         list_del(&jeb->list);
566                 }
567                 if (jffs2_wbuf_dirty(c)) {
568                         D1(printk(KERN_DEBUG "...and adding to erasable_pending_wbuf_list\n"));
569                         list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list);
570                 } else {
571                         if (jiffies & 127) {
572                                 /* Most of the time, we just erase it immediately. Otherwise we
573                                    spend ages scanning it on mount, etc. */
574                                 D1(printk(KERN_DEBUG "...and adding to erase_pending_list\n"));
575                                 list_add_tail(&jeb->list, &c->erase_pending_list);
576                                 c->nr_erasing_blocks++;
577                                 jffs2_erase_pending_trigger(c);
578                         } else {
579                                 /* Sometimes, however, we leave it elsewhere so it doesn't get
580                                    immediately reused, and we spread the load a bit. */
581                                 D1(printk(KERN_DEBUG "...and adding to erasable_list\n"));
582                                 list_add_tail(&jeb->list, &c->erasable_list);
583                         }
584                 }
585                 D1(printk(KERN_DEBUG "Done OK\n"));
586         } else if (jeb == c->gcblock) {
587                 D2(printk(KERN_DEBUG "Not moving gcblock 0x%08x to dirty_list\n", jeb->offset));
588         } else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) {
589                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n", jeb->offset));
590                 list_del(&jeb->list);
591                 D1(printk(KERN_DEBUG "...and adding to dirty_list\n"));
592                 list_add_tail(&jeb->list, &c->dirty_list);
593         } else if (VERYDIRTY(c, jeb->dirty_size) &&
594                    !VERYDIRTY(c, jeb->dirty_size - addedsize)) {
595                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n", jeb->offset));
596                 list_del(&jeb->list);
597                 D1(printk(KERN_DEBUG "...and adding to very_dirty_list\n"));
598                 list_add_tail(&jeb->list, &c->very_dirty_list);
599         } else {
600                 D1(printk(KERN_DEBUG "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n",
601                           jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
602         }
603
604         spin_unlock(&c->erase_completion_lock);
605
606         if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) ||
607                 (c->flags & JFFS2_SB_FLAG_BUILDING)) {
608                 /* We didn't lock the erase_free_sem */
609                 return;
610         }
611
612         /* The erase_free_sem is locked, and has been since before we marked the node obsolete
613            and potentially put its eraseblock onto the erase_pending_list. Thus, we know that
614            the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet
615            by jffs2_free_all_node_refs() in erase.c. Which is nice. */
616
617         D1(printk(KERN_DEBUG "obliterating obsoleted node at 0x%08x\n", ref_offset(ref)));
618         ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
619         if (ret) {
620                 printk(KERN_WARNING "Read error reading from obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
621                 goto out_erase_sem;
622         }
623         if (retlen != sizeof(n)) {
624                 printk(KERN_WARNING "Short read from obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
625                 goto out_erase_sem;
626         }
627         if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) {
628                 printk(KERN_WARNING "Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n", je32_to_cpu(n.totlen), freed_len);
629                 goto out_erase_sem;
630         }
631         if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) {
632                 D1(printk(KERN_DEBUG "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n", ref_offset(ref), je16_to_cpu(n.nodetype)));
633                 goto out_erase_sem;
634         }
635         /* XXX FIXME: This is ugly now */
636         n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE);
637         ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
638         if (ret) {
639                 printk(KERN_WARNING "Write error in obliterating obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
640                 goto out_erase_sem;
641         }
642         if (retlen != sizeof(n)) {
643                 printk(KERN_WARNING "Short write in obliterating obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
644                 goto out_erase_sem;
645         }
646
647         /* Nodes which have been marked obsolete no longer need to be
648            associated with any inode. Remove them from the per-inode list.
649
650            Note we can't do this for NAND at the moment because we need
651            obsolete dirent nodes to stay on the lists, because of the
652            horridness in jffs2_garbage_collect_deletion_dirent(). Also
653            because we delete the inocache, and on NAND we need that to
654            stay around until all the nodes are actually erased, in order
655            to stop us from giving the same inode number to another newly
656            created inode. */
657         if (ref->next_in_ino) {
658                 struct jffs2_inode_cache *ic;
659                 struct jffs2_raw_node_ref **p;
660
661                 spin_lock(&c->erase_completion_lock);
662
663                 ic = jffs2_raw_ref_to_ic(ref);
664                 /* It seems we should never call jffs2_mark_node_obsolete() for
665                    XATTR nodes.... yet. Make sure we notice if/when we change
666                    that :) */
667                 BUG_ON(ic->class != RAWNODE_CLASS_INODE_CACHE);
668                 for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino))
669                         ;
670
671                 *p = ref->next_in_ino;
672                 ref->next_in_ino = NULL;
673
674                 if (ic->nodes == (void *)ic && ic->nlink == 0)
675                         jffs2_del_ino_cache(c, ic);
676
677                 spin_unlock(&c->erase_completion_lock);
678         }
679
680
681         /* Merge with the next node in the physical list, if there is one
682            and if it's also obsolete and if it doesn't belong to any inode */
683         if (ref->next_phys && ref_obsolete(ref->next_phys) &&
684             !ref->next_phys->next_in_ino) {
685                 struct jffs2_raw_node_ref *n = ref->next_phys;
686
687                 spin_lock(&c->erase_completion_lock);
688
689 #ifdef TEST_TOTLEN
690                 ref->__totlen += n->__totlen;
691 #endif
692                 ref->next_phys = n->next_phys;
693                 if (jeb->last_node == n) jeb->last_node = ref;
694                 if (jeb->gc_node == n) {
695                         /* gc will be happy continuing gc on this node */
696                         jeb->gc_node=ref;
697                 }
698                 spin_unlock(&c->erase_completion_lock);
699
700                 jffs2_free_raw_node_ref(n);
701         }
702
703         /* Also merge with the previous node in the list, if there is one
704            and that one is obsolete */
705         if (ref != jeb->first_node ) {
706                 struct jffs2_raw_node_ref *p = jeb->first_node;
707
708                 spin_lock(&c->erase_completion_lock);
709
710                 while (p->next_phys != ref)
711                         p = p->next_phys;
712
713                 if (ref_obsolete(p) && !ref->next_in_ino) {
714 #ifdef TEST_TOTLEN
715                         p->__totlen += ref->__totlen;
716 #endif
717                         if (jeb->last_node == ref) {
718                                 jeb->last_node = p;
719                         }
720                         if (jeb->gc_node == ref) {
721                                 /* gc will be happy continuing gc on this node */
722                                 jeb->gc_node=p;
723                         }
724                         p->next_phys = ref->next_phys;
725                         jffs2_free_raw_node_ref(ref);
726                 }
727                 spin_unlock(&c->erase_completion_lock);
728         }
729  out_erase_sem:
730         up(&c->erase_free_sem);
731 }
732
733 int jffs2_thread_should_wake(struct jffs2_sb_info *c)
734 {
735         int ret = 0;
736         uint32_t dirty;
737
738         if (c->unchecked_size) {
739                 D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): unchecked_size %d, checked_ino #%d\n",
740                           c->unchecked_size, c->checked_ino));
741                 return 1;
742         }
743
744         /* dirty_size contains blocks on erase_pending_list
745          * those blocks are counted in c->nr_erasing_blocks.
746          * If one block is actually erased, it is not longer counted as dirty_space
747          * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
748          * with c->nr_erasing_blocks * c->sector_size again.
749          * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
750          * This helps us to force gc and pick eventually a clean block to spread the load.
751          */
752         dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size;
753
754         if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger &&
755                         (dirty > c->nospc_dirty_size))
756                 ret = 1;
757
758         D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x: %s\n",
759                   c->nr_free_blocks, c->nr_erasing_blocks, c->dirty_size, ret?"yes":"no"));
760
761         return ret;
762 }