Root/fs/jffs2/nodelist.c

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#include <linux/kernel.h>
13#include <linux/sched.h>
14#include <linux/fs.h>
15#include <linux/mtd/mtd.h>
16#include <linux/rbtree.h>
17#include <linux/crc32.h>
18#include <linux/slab.h>
19#include <linux/pagemap.h>
20#include "nodelist.h"
21
22static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
23                     struct jffs2_node_frag *this);
24
25void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
26{
27    struct jffs2_full_dirent **prev = list;
28
29    dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
30
31    while ((*prev) && (*prev)->nhash <= new->nhash) {
32        if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
33            /* Duplicate. Free one */
34            if (new->version < (*prev)->version) {
35                dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n",
36                    (*prev)->name, (*prev)->ino);
37                jffs2_mark_node_obsolete(c, new->raw);
38                jffs2_free_full_dirent(new);
39            } else {
40                dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n",
41                    (*prev)->name, (*prev)->ino);
42                new->next = (*prev)->next;
43                /* It may have been a 'placeholder' deletion dirent,
44                   if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
45                if ((*prev)->raw)
46                    jffs2_mark_node_obsolete(c, ((*prev)->raw));
47                jffs2_free_full_dirent(*prev);
48                *prev = new;
49            }
50            return;
51        }
52        prev = &((*prev)->next);
53    }
54    new->next = *prev;
55    *prev = new;
56}
57
58uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
59{
60    struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
61
62    dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
63
64    /* We know frag->ofs <= size. That's what lookup does for us */
65    if (frag && frag->ofs != size) {
66        if (frag->ofs+frag->size > size) {
67            frag->size = size - frag->ofs;
68        }
69        frag = frag_next(frag);
70    }
71    while (frag && frag->ofs >= size) {
72        struct jffs2_node_frag *next = frag_next(frag);
73
74        frag_erase(frag, list);
75        jffs2_obsolete_node_frag(c, frag);
76        frag = next;
77    }
78
79    if (size == 0)
80        return 0;
81
82    frag = frag_last(list);
83
84    /* Sanity check for truncation to longer than we started with... */
85    if (!frag)
86        return 0;
87    if (frag->ofs + frag->size < size)
88        return frag->ofs + frag->size;
89
90    /* If the last fragment starts at the RAM page boundary, it is
91     * REF_PRISTINE irrespective of its size. */
92    if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
93        dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
94            frag->ofs, frag->ofs + frag->size);
95        frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
96    }
97    return size;
98}
99
100static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
101                     struct jffs2_node_frag *this)
102{
103    if (this->node) {
104        this->node->frags--;
105        if (!this->node->frags) {
106            /* The node has no valid frags left. It's totally obsoleted */
107            dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
108                ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
109            jffs2_mark_node_obsolete(c, this->node->raw);
110            jffs2_free_full_dnode(this->node);
111        } else {
112            dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
113                ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
114            mark_ref_normal(this->node->raw);
115        }
116
117    }
118    jffs2_free_node_frag(this);
119}
120
121static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
122{
123    struct rb_node *parent = &base->rb;
124    struct rb_node **link = &parent;
125
126    dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
127
128    while (*link) {
129        parent = *link;
130        base = rb_entry(parent, struct jffs2_node_frag, rb);
131
132        if (newfrag->ofs > base->ofs)
133            link = &base->rb.rb_right;
134        else if (newfrag->ofs < base->ofs)
135            link = &base->rb.rb_left;
136        else {
137            JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
138            BUG();
139        }
140    }
141
142    rb_link_node(&newfrag->rb, &base->rb, link);
143}
144
145/*
146 * Allocate and initializes a new fragment.
147 */
148static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
149{
150    struct jffs2_node_frag *newfrag;
151
152    newfrag = jffs2_alloc_node_frag();
153    if (likely(newfrag)) {
154        newfrag->ofs = ofs;
155        newfrag->size = size;
156        newfrag->node = fn;
157    } else {
158        JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
159    }
160
161    return newfrag;
162}
163
164/*
165 * Called when there is no overlapping fragment exist. Inserts a hole before the new
166 * fragment and inserts the new fragment to the fragtree.
167 */
168static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
169                    struct jffs2_node_frag *newfrag,
170                   struct jffs2_node_frag *this, uint32_t lastend)
171{
172    if (lastend < newfrag->node->ofs) {
173        /* put a hole in before the new fragment */
174        struct jffs2_node_frag *holefrag;
175
176        holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
177        if (unlikely(!holefrag)) {
178            jffs2_free_node_frag(newfrag);
179            return -ENOMEM;
180        }
181
182        if (this) {
183            /* By definition, the 'this' node has no right-hand child,
184               because there are no frags with offset greater than it.
185               So that's where we want to put the hole */
186            dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
187                holefrag->ofs, holefrag->ofs + holefrag->size);
188            rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
189        } else {
190            dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
191                holefrag->ofs, holefrag->ofs + holefrag->size);
192            rb_link_node(&holefrag->rb, NULL, &root->rb_node);
193        }
194        rb_insert_color(&holefrag->rb, root);
195        this = holefrag;
196    }
197
198    if (this) {
199        /* By definition, the 'this' node has no right-hand child,
200           because there are no frags with offset greater than it.
201           So that's where we want to put new fragment */
202        dbg_fragtree2("add the new node at the right\n");
203        rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
204    } else {
205        dbg_fragtree2("insert the new node at the root of the tree\n");
206        rb_link_node(&newfrag->rb, NULL, &root->rb_node);
207    }
208    rb_insert_color(&newfrag->rb, root);
209
210    return 0;
211}
212
213/* Doesn't set inode->i_size */
214static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
215{
216    struct jffs2_node_frag *this;
217    uint32_t lastend;
218
219    /* Skip all the nodes which are completed before this one starts */
220    this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
221
222    if (this) {
223        dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
224              this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
225        lastend = this->ofs + this->size;
226    } else {
227        dbg_fragtree2("lookup gave no frag\n");
228        lastend = 0;
229    }
230
231    /* See if we ran off the end of the fragtree */
232    if (lastend <= newfrag->ofs) {
233        /* We did */
234
235        /* Check if 'this' node was on the same page as the new node.
236           If so, both 'this' and the new node get marked REF_NORMAL so
237           the GC can take a look.
238        */
239        if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
240            if (this->node)
241                mark_ref_normal(this->node->raw);
242            mark_ref_normal(newfrag->node->raw);
243        }
244
245        return no_overlapping_node(c, root, newfrag, this, lastend);
246    }
247
248    if (this->node)
249        dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
250        this->ofs, this->ofs + this->size,
251        ref_offset(this->node->raw), ref_flags(this->node->raw));
252    else
253        dbg_fragtree2("dealing with hole frag %u-%u.\n",
254        this->ofs, this->ofs + this->size);
255
256    /* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
257     * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
258     */
259    if (newfrag->ofs > this->ofs) {
260        /* This node isn't completely obsoleted. The start of it remains valid */
261
262        /* Mark the new node and the partially covered node REF_NORMAL -- let
263           the GC take a look at them */
264        mark_ref_normal(newfrag->node->raw);
265        if (this->node)
266            mark_ref_normal(this->node->raw);
267
268        if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
269            /* The new node splits 'this' frag into two */
270            struct jffs2_node_frag *newfrag2;
271
272            if (this->node)
273                dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
274                    this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
275            else
276                dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
277                    this->ofs, this->ofs+this->size);
278
279            /* New second frag pointing to this's node */
280            newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
281                        this->ofs + this->size - newfrag->ofs - newfrag->size);
282            if (unlikely(!newfrag2))
283                return -ENOMEM;
284            if (this->node)
285                this->node->frags++;
286
287            /* Adjust size of original 'this' */
288            this->size = newfrag->ofs - this->ofs;
289
290            /* Now, we know there's no node with offset
291               greater than this->ofs but smaller than
292               newfrag2->ofs or newfrag->ofs, for obvious
293               reasons. So we can do a tree insert from
294               'this' to insert newfrag, and a tree insert
295               from newfrag to insert newfrag2. */
296            jffs2_fragtree_insert(newfrag, this);
297            rb_insert_color(&newfrag->rb, root);
298
299            jffs2_fragtree_insert(newfrag2, newfrag);
300            rb_insert_color(&newfrag2->rb, root);
301
302            return 0;
303        }
304        /* New node just reduces 'this' frag in size, doesn't split it */
305        this->size = newfrag->ofs - this->ofs;
306
307        /* Again, we know it lives down here in the tree */
308        jffs2_fragtree_insert(newfrag, this);
309        rb_insert_color(&newfrag->rb, root);
310    } else {
311        /* New frag starts at the same point as 'this' used to. Replace
312           it in the tree without doing a delete and insertion */
313        dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
314              newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
315
316        rb_replace_node(&this->rb, &newfrag->rb, root);
317
318        if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
319            dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
320            jffs2_obsolete_node_frag(c, this);
321        } else {
322            this->ofs += newfrag->size;
323            this->size -= newfrag->size;
324
325            jffs2_fragtree_insert(this, newfrag);
326            rb_insert_color(&this->rb, root);
327            return 0;
328        }
329    }
330    /* OK, now we have newfrag added in the correct place in the tree, but
331       frag_next(newfrag) may be a fragment which is overlapped by it
332    */
333    while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
334        /* 'this' frag is obsoleted completely. */
335        dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
336            this, this->ofs, this->ofs+this->size);
337        rb_erase(&this->rb, root);
338        jffs2_obsolete_node_frag(c, this);
339    }
340    /* Now we're pointing at the first frag which isn't totally obsoleted by
341       the new frag */
342
343    if (!this || newfrag->ofs + newfrag->size == this->ofs)
344        return 0;
345
346    /* Still some overlap but we don't need to move it in the tree */
347    this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
348    this->ofs = newfrag->ofs + newfrag->size;
349
350    /* And mark them REF_NORMAL so the GC takes a look at them */
351    if (this->node)
352        mark_ref_normal(this->node->raw);
353    mark_ref_normal(newfrag->node->raw);
354
355    return 0;
356}
357
358/*
359 * Given an inode, probably with existing tree of fragments, add the new node
360 * to the fragment tree.
361 */
362int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
363{
364    int ret;
365    struct jffs2_node_frag *newfrag;
366
367    if (unlikely(!fn->size))
368        return 0;
369
370    newfrag = new_fragment(fn, fn->ofs, fn->size);
371    if (unlikely(!newfrag))
372        return -ENOMEM;
373    newfrag->node->frags = 1;
374
375    dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
376          fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
377
378    ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
379    if (unlikely(ret))
380        return ret;
381
382    /* If we now share a page with other nodes, mark either previous
383       or next node REF_NORMAL, as appropriate. */
384    if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
385        struct jffs2_node_frag *prev = frag_prev(newfrag);
386
387        mark_ref_normal(fn->raw);
388        /* If we don't start at zero there's _always_ a previous */
389        if (prev->node)
390            mark_ref_normal(prev->node->raw);
391    }
392
393    if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
394        struct jffs2_node_frag *next = frag_next(newfrag);
395
396        if (next) {
397            mark_ref_normal(fn->raw);
398            if (next->node)
399                mark_ref_normal(next->node->raw);
400        }
401    }
402    jffs2_dbg_fragtree_paranoia_check_nolock(f);
403
404    return 0;
405}
406
407void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
408{
409    spin_lock(&c->inocache_lock);
410    ic->state = state;
411    wake_up(&c->inocache_wq);
412    spin_unlock(&c->inocache_lock);
413}
414
415/* During mount, this needs no locking. During normal operation, its
416   callers want to do other stuff while still holding the inocache_lock.
417   Rather than introducing special case get_ino_cache functions or
418   callbacks, we just let the caller do the locking itself. */
419
420struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
421{
422    struct jffs2_inode_cache *ret;
423
424    ret = c->inocache_list[ino % INOCACHE_HASHSIZE];
425    while (ret && ret->ino < ino) {
426        ret = ret->next;
427    }
428
429    if (ret && ret->ino != ino)
430        ret = NULL;
431
432    return ret;
433}
434
435void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
436{
437    struct jffs2_inode_cache **prev;
438
439    spin_lock(&c->inocache_lock);
440    if (!new->ino)
441        new->ino = ++c->highest_ino;
442
443    dbg_inocache("add %p (ino #%u)\n", new, new->ino);
444
445    prev = &c->inocache_list[new->ino % INOCACHE_HASHSIZE];
446
447    while ((*prev) && (*prev)->ino < new->ino) {
448        prev = &(*prev)->next;
449    }
450    new->next = *prev;
451    *prev = new;
452
453    spin_unlock(&c->inocache_lock);
454}
455
456void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
457{
458    struct jffs2_inode_cache **prev;
459
460#ifdef CONFIG_JFFS2_FS_XATTR
461    BUG_ON(old->xref);
462#endif
463    dbg_inocache("del %p (ino #%u)\n", old, old->ino);
464    spin_lock(&c->inocache_lock);
465
466    prev = &c->inocache_list[old->ino % INOCACHE_HASHSIZE];
467
468    while ((*prev) && (*prev)->ino < old->ino) {
469        prev = &(*prev)->next;
470    }
471    if ((*prev) == old) {
472        *prev = old->next;
473    }
474
475    /* Free it now unless it's in READING or CLEARING state, which
476       are the transitions upon read_inode() and clear_inode(). The
477       rest of the time we know nobody else is looking at it, and
478       if it's held by read_inode() or clear_inode() they'll free it
479       for themselves. */
480    if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
481        jffs2_free_inode_cache(old);
482
483    spin_unlock(&c->inocache_lock);
484}
485
486void jffs2_free_ino_caches(struct jffs2_sb_info *c)
487{
488    int i;
489    struct jffs2_inode_cache *this, *next;
490
491    for (i=0; i<INOCACHE_HASHSIZE; i++) {
492        this = c->inocache_list[i];
493        while (this) {
494            next = this->next;
495            jffs2_xattr_free_inode(c, this);
496            jffs2_free_inode_cache(this);
497            this = next;
498        }
499        c->inocache_list[i] = NULL;
500    }
501}
502
503void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
504{
505    int i;
506    struct jffs2_raw_node_ref *this, *next;
507
508    for (i=0; i<c->nr_blocks; i++) {
509        this = c->blocks[i].first_node;
510        while (this) {
511            if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
512                next = this[REFS_PER_BLOCK].next_in_ino;
513            else
514                next = NULL;
515
516            jffs2_free_refblock(this);
517            this = next;
518        }
519        c->blocks[i].first_node = c->blocks[i].last_node = NULL;
520    }
521}
522
523struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
524{
525    /* The common case in lookup is that there will be a node
526       which precisely matches. So we go looking for that first */
527    struct rb_node *next;
528    struct jffs2_node_frag *prev = NULL;
529    struct jffs2_node_frag *frag = NULL;
530
531    dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
532
533    next = fragtree->rb_node;
534
535    while(next) {
536        frag = rb_entry(next, struct jffs2_node_frag, rb);
537
538        if (frag->ofs + frag->size <= offset) {
539            /* Remember the closest smaller match on the way down */
540            if (!prev || frag->ofs > prev->ofs)
541                prev = frag;
542            next = frag->rb.rb_right;
543        } else if (frag->ofs > offset) {
544            next = frag->rb.rb_left;
545        } else {
546            return frag;
547        }
548    }
549
550    /* Exact match not found. Go back up looking at each parent,
551       and return the closest smaller one */
552
553    if (prev)
554        dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
555              prev->ofs, prev->ofs+prev->size);
556    else
557        dbg_fragtree2("returning NULL, empty fragtree\n");
558
559    return prev;
560}
561
562/* Pass 'c' argument to indicate that nodes should be marked obsolete as
563   they're killed. */
564void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
565{
566    struct jffs2_node_frag *frag;
567    struct jffs2_node_frag *parent;
568
569    if (!root->rb_node)
570        return;
571
572    dbg_fragtree("killing\n");
573
574    frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));
575    while(frag) {
576        if (frag->rb.rb_left) {
577            frag = frag_left(frag);
578            continue;
579        }
580        if (frag->rb.rb_right) {
581            frag = frag_right(frag);
582            continue;
583        }
584
585        if (frag->node && !(--frag->node->frags)) {
586            /* Not a hole, and it's the final remaining frag
587               of this node. Free the node */
588            if (c)
589                jffs2_mark_node_obsolete(c, frag->node->raw);
590
591            jffs2_free_full_dnode(frag->node);
592        }
593        parent = frag_parent(frag);
594        if (parent) {
595            if (frag_left(parent) == frag)
596                parent->rb.rb_left = NULL;
597            else
598                parent->rb.rb_right = NULL;
599        }
600
601        jffs2_free_node_frag(frag);
602        frag = parent;
603
604        cond_resched();
605    }
606}
607
608struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
609                           struct jffs2_eraseblock *jeb,
610                           uint32_t ofs, uint32_t len,
611                           struct jffs2_inode_cache *ic)
612{
613    struct jffs2_raw_node_ref *ref;
614
615    BUG_ON(!jeb->allocated_refs);
616    jeb->allocated_refs--;
617
618    ref = jeb->last_node;
619
620    dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
621            ref->next_in_ino);
622
623    while (ref->flash_offset != REF_EMPTY_NODE) {
624        if (ref->flash_offset == REF_LINK_NODE)
625            ref = ref->next_in_ino;
626        else
627            ref++;
628    }
629
630    dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref,
631            ref->flash_offset, ofs, ref->next_in_ino, len);
632
633    ref->flash_offset = ofs;
634
635    if (!jeb->first_node) {
636        jeb->first_node = ref;
637        BUG_ON(ref_offset(ref) != jeb->offset);
638    } else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
639        uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
640
641        JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
642                ref, ref_offset(ref), ref_offset(ref)+len,
643                ref_offset(jeb->last_node),
644                ref_offset(jeb->last_node)+last_len);
645        BUG();
646    }
647    jeb->last_node = ref;
648
649    if (ic) {
650        ref->next_in_ino = ic->nodes;
651        ic->nodes = ref;
652    } else {
653        ref->next_in_ino = NULL;
654    }
655
656    switch(ref_flags(ref)) {
657    case REF_UNCHECKED:
658        c->unchecked_size += len;
659        jeb->unchecked_size += len;
660        break;
661
662    case REF_NORMAL:
663    case REF_PRISTINE:
664        c->used_size += len;
665        jeb->used_size += len;
666        break;
667
668    case REF_OBSOLETE:
669        c->dirty_size += len;
670        jeb->dirty_size += len;
671        break;
672    }
673    c->free_size -= len;
674    jeb->free_size -= len;
675
676#ifdef TEST_TOTLEN
677    /* Set (and test) __totlen field... for now */
678    ref->__totlen = len;
679    ref_totlen(c, jeb, ref);
680#endif
681    return ref;
682}
683
684/* No locking, no reservation of 'ref'. Do not use on a live file system */
685int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
686               uint32_t size)
687{
688    if (!size)
689        return 0;
690    if (unlikely(size > jeb->free_size)) {
691        printk(KERN_CRIT "Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
692               size, jeb->free_size, jeb->wasted_size);
693        BUG();
694    }
695    /* REF_EMPTY_NODE is !obsolete, so that works OK */
696    if (jeb->last_node && ref_obsolete(jeb->last_node)) {
697#ifdef TEST_TOTLEN
698        jeb->last_node->__totlen += size;
699#endif
700        c->dirty_size += size;
701        c->free_size -= size;
702        jeb->dirty_size += size;
703        jeb->free_size -= size;
704    } else {
705        uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
706        ofs |= REF_OBSOLETE;
707
708        jffs2_link_node_ref(c, jeb, ofs, size, NULL);
709    }
710
711    return 0;
712}
713
714/* Calculate totlen from surrounding nodes or eraseblock */
715static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
716                    struct jffs2_eraseblock *jeb,
717                    struct jffs2_raw_node_ref *ref)
718{
719    uint32_t ref_end;
720    struct jffs2_raw_node_ref *next_ref = ref_next(ref);
721
722    if (next_ref)
723        ref_end = ref_offset(next_ref);
724    else {
725        if (!jeb)
726            jeb = &c->blocks[ref->flash_offset / c->sector_size];
727
728        /* Last node in block. Use free_space */
729        if (unlikely(ref != jeb->last_node)) {
730            printk(KERN_CRIT "ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
731                   ref, ref_offset(ref), jeb->last_node, jeb->last_node?ref_offset(jeb->last_node):0);
732            BUG();
733        }
734        ref_end = jeb->offset + c->sector_size - jeb->free_size;
735    }
736    return ref_end - ref_offset(ref);
737}
738
739uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
740                struct jffs2_raw_node_ref *ref)
741{
742    uint32_t ret;
743
744    ret = __ref_totlen(c, jeb, ref);
745
746#ifdef TEST_TOTLEN
747    if (unlikely(ret != ref->__totlen)) {
748        if (!jeb)
749            jeb = &c->blocks[ref->flash_offset / c->sector_size];
750
751        printk(KERN_CRIT "Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
752               ref, ref_offset(ref), ref_offset(ref)+ref->__totlen,
753               ret, ref->__totlen);
754        if (ref_next(ref)) {
755            printk(KERN_CRIT "next %p (0x%08x-0x%08x)\n", ref_next(ref), ref_offset(ref_next(ref)),
756                   ref_offset(ref_next(ref))+ref->__totlen);
757        } else
758            printk(KERN_CRIT "No next ref. jeb->last_node is %p\n", jeb->last_node);
759
760        printk(KERN_CRIT "jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x\n", jeb->wasted_size, jeb->dirty_size, jeb->used_size, jeb->free_size);
761
762#if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
763        __jffs2_dbg_dump_node_refs_nolock(c, jeb);
764#endif
765
766        WARN_ON(1);
767
768        ret = ref->__totlen;
769    }
770#endif /* TEST_TOTLEN */
771    return ret;
772}
773

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