1/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright © 2001-2007 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/kernel.h>
15#include <linux/sched.h>
16#include <linux/fs.h>
17#include <linux/mtd/mtd.h>
18#include <linux/rbtree.h>
19#include <linux/crc32.h>
20#include <linux/pagemap.h>
21#include "nodelist.h"
22
23static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
24				     struct jffs2_node_frag *this);
25
26void jffs2_add_fd_to_list(struct jffs2_sb_info *c, struct jffs2_full_dirent *new, struct jffs2_full_dirent **list)
27{
28	struct jffs2_full_dirent **prev = list;
29
30	dbg_dentlist("add dirent \"%s\", ino #%u\n", new->name, new->ino);
31
32	while ((*prev) && (*prev)->nhash <= new->nhash) {
33		if ((*prev)->nhash == new->nhash && !strcmp((*prev)->name, new->name)) {
34			/* Duplicate. Free one */
35			if (new->version < (*prev)->version) {
36				dbg_dentlist("Eep! Marking new dirent node obsolete, old is \"%s\", ino #%u\n",
37					(*prev)->name, (*prev)->ino);
38				jffs2_mark_node_obsolete(c, new->raw);
39				jffs2_free_full_dirent(new);
40			} else {
41				dbg_dentlist("marking old dirent \"%s\", ino #%u obsolete\n",
42					(*prev)->name, (*prev)->ino);
43				new->next = (*prev)->next;
44				/* It may have been a 'placeholder' deletion dirent,
45				   if jffs2_can_mark_obsolete() (see jffs2_do_unlink()) */
46				if ((*prev)->raw)
47					jffs2_mark_node_obsolete(c, ((*prev)->raw));
48				jffs2_free_full_dirent(*prev);
49				*prev = new;
50			}
51			return;
52		}
53		prev = &((*prev)->next);
54	}
55	new->next = *prev;
56	*prev = new;
57}
58
59uint32_t jffs2_truncate_fragtree(struct jffs2_sb_info *c, struct rb_root *list, uint32_t size)
60{
61	struct jffs2_node_frag *frag = jffs2_lookup_node_frag(list, size);
62
63	dbg_fragtree("truncating fragtree to 0x%08x bytes\n", size);
64
65	/* We know frag->ofs <= size. That's what lookup does for us */
66	if (frag && frag->ofs != size) {
67		if (frag->ofs+frag->size > size) {
68			frag->size = size - frag->ofs;
69		}
70		frag = frag_next(frag);
71	}
72	while (frag && frag->ofs >= size) {
73		struct jffs2_node_frag *next = frag_next(frag);
74
75		frag_erase(frag, list);
76		jffs2_obsolete_node_frag(c, frag);
77		frag = next;
78	}
79
80	if (size == 0)
81		return 0;
82
83	frag = frag_last(list);
84
85	/* Sanity check for truncation to longer than we started with... */
86	if (!frag)
87		return 0;
88	if (frag->ofs + frag->size < size)
89		return frag->ofs + frag->size;
90
91	/* If the last fragment starts at the RAM page boundary, it is
92	 * REF_PRISTINE irrespective of its size. */
93	if (frag->node && (frag->ofs & (PAGE_CACHE_SIZE - 1)) == 0) {
94		dbg_fragtree2("marking the last fragment 0x%08x-0x%08x REF_PRISTINE.\n",
95			frag->ofs, frag->ofs + frag->size);
96		frag->node->raw->flash_offset = ref_offset(frag->node->raw) | REF_PRISTINE;
97	}
98	return size;
99}
100
101static void jffs2_obsolete_node_frag(struct jffs2_sb_info *c,
102				     struct jffs2_node_frag *this)
103{
104	if (this->node) {
105		this->node->frags--;
106		if (!this->node->frags) {
107			/* The node has no valid frags left. It's totally obsoleted */
108			dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) obsolete\n",
109				ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size);
110			jffs2_mark_node_obsolete(c, this->node->raw);
111			jffs2_free_full_dnode(this->node);
112		} else {
113			dbg_fragtree2("marking old node @0x%08x (0x%04x-0x%04x) REF_NORMAL. frags is %d\n",
114				ref_offset(this->node->raw), this->node->ofs, this->node->ofs+this->node->size, this->node->frags);
115			mark_ref_normal(this->node->raw);
116		}
117
118	}
119	jffs2_free_node_frag(this);
120}
121
122static void jffs2_fragtree_insert(struct jffs2_node_frag *newfrag, struct jffs2_node_frag *base)
123{
124	struct rb_node *parent = &base->rb;
125	struct rb_node **link = &parent;
126
127	dbg_fragtree2("insert frag (0x%04x-0x%04x)\n", newfrag->ofs, newfrag->ofs + newfrag->size);
128
129	while (*link) {
130		parent = *link;
131		base = rb_entry(parent, struct jffs2_node_frag, rb);
132
133		if (newfrag->ofs > base->ofs)
134			link = &base->rb.rb_right;
135		else if (newfrag->ofs < base->ofs)
136			link = &base->rb.rb_left;
137		else {
138			JFFS2_ERROR("duplicate frag at %08x (%p,%p)\n", newfrag->ofs, newfrag, base);
139			BUG();
140		}
141	}
142
143	rb_link_node(&newfrag->rb, &base->rb, link);
144}
145
146/*
147 * Allocate and initializes a new fragment.
148 */
149static struct jffs2_node_frag * new_fragment(struct jffs2_full_dnode *fn, uint32_t ofs, uint32_t size)
150{
151	struct jffs2_node_frag *newfrag;
152
153	newfrag = jffs2_alloc_node_frag();
154	if (likely(newfrag)) {
155		newfrag->ofs = ofs;
156		newfrag->size = size;
157		newfrag->node = fn;
158	} else {
159		JFFS2_ERROR("cannot allocate a jffs2_node_frag object\n");
160	}
161
162	return newfrag;
163}
164
165/*
166 * Called when there is no overlapping fragment exist. Inserts a hole before the new
167 * fragment and inserts the new fragment to the fragtree.
168 */
169static int no_overlapping_node(struct jffs2_sb_info *c, struct rb_root *root,
170		 	       struct jffs2_node_frag *newfrag,
171			       struct jffs2_node_frag *this, uint32_t lastend)
172{
173	if (lastend < newfrag->node->ofs) {
174		/* put a hole in before the new fragment */
175		struct jffs2_node_frag *holefrag;
176
177		holefrag= new_fragment(NULL, lastend, newfrag->node->ofs - lastend);
178		if (unlikely(!holefrag)) {
179			jffs2_free_node_frag(newfrag);
180			return -ENOMEM;
181		}
182
183		if (this) {
184			/* By definition, the 'this' node has no right-hand child,
185			   because there are no frags with offset greater than it.
186			   So that's where we want to put the hole */
187			dbg_fragtree2("add hole frag %#04x-%#04x on the right of the new frag.\n",
188				holefrag->ofs, holefrag->ofs + holefrag->size);
189			rb_link_node(&holefrag->rb, &this->rb, &this->rb.rb_right);
190		} else {
191			dbg_fragtree2("Add hole frag %#04x-%#04x to the root of the tree.\n",
192				holefrag->ofs, holefrag->ofs + holefrag->size);
193			rb_link_node(&holefrag->rb, NULL, &root->rb_node);
194		}
195		rb_insert_color(&holefrag->rb, root);
196		this = holefrag;
197	}
198
199	if (this) {
200		/* By definition, the 'this' node has no right-hand child,
201		   because there are no frags with offset greater than it.
202		   So that's where we want to put new fragment */
203		dbg_fragtree2("add the new node at the right\n");
204		rb_link_node(&newfrag->rb, &this->rb, &this->rb.rb_right);
205	} else {
206		dbg_fragtree2("insert the new node at the root of the tree\n");
207		rb_link_node(&newfrag->rb, NULL, &root->rb_node);
208	}
209	rb_insert_color(&newfrag->rb, root);
210
211	return 0;
212}
213
214/* Doesn't set inode->i_size */
215static int jffs2_add_frag_to_fragtree(struct jffs2_sb_info *c, struct rb_root *root, struct jffs2_node_frag *newfrag)
216{
217	struct jffs2_node_frag *this;
218	uint32_t lastend;
219
220	/* Skip all the nodes which are completed before this one starts */
221	this = jffs2_lookup_node_frag(root, newfrag->node->ofs);
222
223	if (this) {
224		dbg_fragtree2("lookup gave frag 0x%04x-0x%04x; phys 0x%08x (*%p)\n",
225			  this->ofs, this->ofs+this->size, this->node?(ref_offset(this->node->raw)):0xffffffff, this);
226		lastend = this->ofs + this->size;
227	} else {
228		dbg_fragtree2("lookup gave no frag\n");
229		lastend = 0;
230	}
231
232	/* See if we ran off the end of the fragtree */
233	if (lastend <= newfrag->ofs) {
234		/* We did */
235
236		/* Check if 'this' node was on the same page as the new node.
237		   If so, both 'this' and the new node get marked REF_NORMAL so
238		   the GC can take a look.
239		*/
240		if (lastend && (lastend-1) >> PAGE_CACHE_SHIFT == newfrag->ofs >> PAGE_CACHE_SHIFT) {
241			if (this->node)
242				mark_ref_normal(this->node->raw);
243			mark_ref_normal(newfrag->node->raw);
244		}
245
246		return no_overlapping_node(c, root, newfrag, this, lastend);
247	}
248
249	if (this->node)
250		dbg_fragtree2("dealing with frag %u-%u, phys %#08x(%d).\n",
251		this->ofs, this->ofs + this->size,
252		ref_offset(this->node->raw), ref_flags(this->node->raw));
253	else
254		dbg_fragtree2("dealing with hole frag %u-%u.\n",
255		this->ofs, this->ofs + this->size);
256
257	/* OK. 'this' is pointing at the first frag that newfrag->ofs at least partially obsoletes,
258	 * - i.e. newfrag->ofs < this->ofs+this->size && newfrag->ofs >= this->ofs
259	 */
260	if (newfrag->ofs > this->ofs) {
261		/* This node isn't completely obsoleted. The start of it remains valid */
262
263		/* Mark the new node and the partially covered node REF_NORMAL -- let
264		   the GC take a look at them */
265		mark_ref_normal(newfrag->node->raw);
266		if (this->node)
267			mark_ref_normal(this->node->raw);
268
269		if (this->ofs + this->size > newfrag->ofs + newfrag->size) {
270			/* The new node splits 'this' frag into two */
271			struct jffs2_node_frag *newfrag2;
272
273			if (this->node)
274				dbg_fragtree2("split old frag 0x%04x-0x%04x, phys 0x%08x\n",
275					this->ofs, this->ofs+this->size, ref_offset(this->node->raw));
276			else
277				dbg_fragtree2("split old hole frag 0x%04x-0x%04x\n",
278					this->ofs, this->ofs+this->size);
279
280			/* New second frag pointing to this's node */
281			newfrag2 = new_fragment(this->node, newfrag->ofs + newfrag->size,
282						this->ofs + this->size - newfrag->ofs - newfrag->size);
283			if (unlikely(!newfrag2))
284				return -ENOMEM;
285			if (this->node)
286				this->node->frags++;
287
288			/* Adjust size of original 'this' */
289			this->size = newfrag->ofs - this->ofs;
290
291			/* Now, we know there's no node with offset
292			   greater than this->ofs but smaller than
293			   newfrag2->ofs or newfrag->ofs, for obvious
294			   reasons. So we can do a tree insert from
295			   'this' to insert newfrag, and a tree insert
296			   from newfrag to insert newfrag2. */
297			jffs2_fragtree_insert(newfrag, this);
298			rb_insert_color(&newfrag->rb, root);
299
300			jffs2_fragtree_insert(newfrag2, newfrag);
301			rb_insert_color(&newfrag2->rb, root);
302
303			return 0;
304		}
305		/* New node just reduces 'this' frag in size, doesn't split it */
306		this->size = newfrag->ofs - this->ofs;
307
308		/* Again, we know it lives down here in the tree */
309		jffs2_fragtree_insert(newfrag, this);
310		rb_insert_color(&newfrag->rb, root);
311	} else {
312		/* New frag starts at the same point as 'this' used to. Replace
313		   it in the tree without doing a delete and insertion */
314		dbg_fragtree2("inserting newfrag (*%p),%d-%d in before 'this' (*%p),%d-%d\n",
315			  newfrag, newfrag->ofs, newfrag->ofs+newfrag->size, this, this->ofs, this->ofs+this->size);
316
317		rb_replace_node(&this->rb, &newfrag->rb, root);
318
319		if (newfrag->ofs + newfrag->size >= this->ofs+this->size) {
320			dbg_fragtree2("obsoleting node frag %p (%x-%x)\n", this, this->ofs, this->ofs+this->size);
321			jffs2_obsolete_node_frag(c, this);
322		} else {
323			this->ofs += newfrag->size;
324			this->size -= newfrag->size;
325
326			jffs2_fragtree_insert(this, newfrag);
327			rb_insert_color(&this->rb, root);
328			return 0;
329		}
330	}
331	/* OK, now we have newfrag added in the correct place in the tree, but
332	   frag_next(newfrag) may be a fragment which is overlapped by it
333	*/
334	while ((this = frag_next(newfrag)) && newfrag->ofs + newfrag->size >= this->ofs + this->size) {
335		/* 'this' frag is obsoleted completely. */
336		dbg_fragtree2("obsoleting node frag %p (%x-%x) and removing from tree\n",
337			this, this->ofs, this->ofs+this->size);
338		rb_erase(&this->rb, root);
339		jffs2_obsolete_node_frag(c, this);
340	}
341	/* Now we're pointing at the first frag which isn't totally obsoleted by
342	   the new frag */
343
344	if (!this || newfrag->ofs + newfrag->size == this->ofs)
345		return 0;
346
347	/* Still some overlap but we don't need to move it in the tree */
348	this->size = (this->ofs + this->size) - (newfrag->ofs + newfrag->size);
349	this->ofs = newfrag->ofs + newfrag->size;
350
351	/* And mark them REF_NORMAL so the GC takes a look at them */
352	if (this->node)
353		mark_ref_normal(this->node->raw);
354	mark_ref_normal(newfrag->node->raw);
355
356	return 0;
357}
358
359/*
360 * Given an inode, probably with existing tree of fragments, add the new node
361 * to the fragment tree.
362 */
363int jffs2_add_full_dnode_to_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f, struct jffs2_full_dnode *fn)
364{
365	int ret;
366	struct jffs2_node_frag *newfrag;
367
368	if (unlikely(!fn->size))
369		return 0;
370
371	newfrag = new_fragment(fn, fn->ofs, fn->size);
372	if (unlikely(!newfrag))
373		return -ENOMEM;
374	newfrag->node->frags = 1;
375
376	dbg_fragtree("adding node %#04x-%#04x @0x%08x on flash, newfrag *%p\n",
377		  fn->ofs, fn->ofs+fn->size, ref_offset(fn->raw), newfrag);
378
379	ret = jffs2_add_frag_to_fragtree(c, &f->fragtree, newfrag);
380	if (unlikely(ret))
381		return ret;
382
383	/* If we now share a page with other nodes, mark either previous
384	   or next node REF_NORMAL, as appropriate.  */
385	if (newfrag->ofs & (PAGE_CACHE_SIZE-1)) {
386		struct jffs2_node_frag *prev = frag_prev(newfrag);
387
388		mark_ref_normal(fn->raw);
389		/* If we don't start at zero there's _always_ a previous */
390		if (prev->node)
391			mark_ref_normal(prev->node->raw);
392	}
393
394	if ((newfrag->ofs+newfrag->size) & (PAGE_CACHE_SIZE-1)) {
395		struct jffs2_node_frag *next = frag_next(newfrag);
396
397		if (next) {
398			mark_ref_normal(fn->raw);
399			if (next->node)
400				mark_ref_normal(next->node->raw);
401		}
402	}
403	jffs2_dbg_fragtree_paranoia_check_nolock(f);
404
405	return 0;
406}
407
408void jffs2_set_inocache_state(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic, int state)
409{
410	spin_lock(&c->inocache_lock);
411	ic->state = state;
412	wake_up(&c->inocache_wq);
413	spin_unlock(&c->inocache_lock);
414}
415
416/* During mount, this needs no locking. During normal operation, its
417   callers want to do other stuff while still holding the inocache_lock.
418   Rather than introducing special case get_ino_cache functions or
419   callbacks, we just let the caller do the locking itself. */
420
421struct jffs2_inode_cache *jffs2_get_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
422{
423	struct jffs2_inode_cache *ret;
424
425	ret = c->inocache_list[ino % c->inocache_hashsize];
426	while (ret && ret->ino < ino) {
427		ret = ret->next;
428	}
429
430	if (ret && ret->ino != ino)
431		ret = NULL;
432
433	return ret;
434}
435
436void jffs2_add_ino_cache (struct jffs2_sb_info *c, struct jffs2_inode_cache *new)
437{
438	struct jffs2_inode_cache **prev;
439
440	spin_lock(&c->inocache_lock);
441	if (!new->ino)
442		new->ino = ++c->highest_ino;
443
444	dbg_inocache("add %p (ino #%u)\n", new, new->ino);
445
446	prev = &c->inocache_list[new->ino % c->inocache_hashsize];
447
448	while ((*prev) && (*prev)->ino < new->ino) {
449		prev = &(*prev)->next;
450	}
451	new->next = *prev;
452	*prev = new;
453
454	spin_unlock(&c->inocache_lock);
455}
456
457void jffs2_del_ino_cache(struct jffs2_sb_info *c, struct jffs2_inode_cache *old)
458{
459	struct jffs2_inode_cache **prev;
460
461#ifdef CONFIG_JFFS2_FS_XATTR
462	BUG_ON(old->xref);
463#endif
464	dbg_inocache("del %p (ino #%u)\n", old, old->ino);
465	spin_lock(&c->inocache_lock);
466
467	prev = &c->inocache_list[old->ino % c->inocache_hashsize];
468
469	while ((*prev) && (*prev)->ino < old->ino) {
470		prev = &(*prev)->next;
471	}
472	if ((*prev) == old) {
473		*prev = old->next;
474	}
475
476	/* Free it now unless it's in READING or CLEARING state, which
477	   are the transitions upon read_inode() and clear_inode(). The
478	   rest of the time we know nobody else is looking at it, and
479	   if it's held by read_inode() or clear_inode() they'll free it
480	   for themselves. */
481	if (old->state != INO_STATE_READING && old->state != INO_STATE_CLEARING)
482		jffs2_free_inode_cache(old);
483
484	spin_unlock(&c->inocache_lock);
485}
486
487void jffs2_free_ino_caches(struct jffs2_sb_info *c)
488{
489	int i;
490	struct jffs2_inode_cache *this, *next;
491
492	for (i=0; i < c->inocache_hashsize; i++) {
493		this = c->inocache_list[i];
494		while (this) {
495			next = this->next;
496			jffs2_xattr_free_inode(c, this);
497			jffs2_free_inode_cache(this);
498			this = next;
499		}
500		c->inocache_list[i] = NULL;
501	}
502}
503
504void jffs2_free_raw_node_refs(struct jffs2_sb_info *c)
505{
506	int i;
507	struct jffs2_raw_node_ref *this, *next;
508
509	for (i=0; i<c->nr_blocks; i++) {
510		this = c->blocks[i].first_node;
511		while (this) {
512			if (this[REFS_PER_BLOCK].flash_offset == REF_LINK_NODE)
513				next = this[REFS_PER_BLOCK].next_in_ino;
514			else
515				next = NULL;
516
517			jffs2_free_refblock(this);
518			this = next;
519		}
520		c->blocks[i].first_node = c->blocks[i].last_node = NULL;
521	}
522}
523
524struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_t offset)
525{
526	/* The common case in lookup is that there will be a node
527	   which precisely matches. So we go looking for that first */
528	struct rb_node *next;
529	struct jffs2_node_frag *prev = NULL;
530	struct jffs2_node_frag *frag = NULL;
531
532	dbg_fragtree2("root %p, offset %d\n", fragtree, offset);
533
534	next = fragtree->rb_node;
535
536	while(next) {
537		frag = rb_entry(next, struct jffs2_node_frag, rb);
538
539		if (frag->ofs + frag->size <= offset) {
540			/* Remember the closest smaller match on the way down */
541			if (!prev || frag->ofs > prev->ofs)
542				prev = frag;
543			next = frag->rb.rb_right;
544		} else if (frag->ofs > offset) {
545			next = frag->rb.rb_left;
546		} else {
547			return frag;
548		}
549	}
550
551	/* Exact match not found. Go back up looking at each parent,
552	   and return the closest smaller one */
553
554	if (prev)
555		dbg_fragtree2("no match. Returning frag %#04x-%#04x, closest previous\n",
556			  prev->ofs, prev->ofs+prev->size);
557	else
558		dbg_fragtree2("returning NULL, empty fragtree\n");
559
560	return prev;
561}
562
563/* Pass 'c' argument to indicate that nodes should be marked obsolete as
564   they're killed. */
565void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
566{
567	struct jffs2_node_frag *frag, *next;
568
569	dbg_fragtree("killing\n");
570	rbtree_postorder_for_each_entry_safe(frag, next, root, rb) {
571		if (frag->node && !(--frag->node->frags)) {
572			/* Not a hole, and it's the final remaining frag
573			   of this node. Free the node */
574			if (c)
575				jffs2_mark_node_obsolete(c, frag->node->raw);
576
577			jffs2_free_full_dnode(frag->node);
578		}
579
580		jffs2_free_node_frag(frag);
581		cond_resched();
582	}
583}
584
585struct jffs2_raw_node_ref *jffs2_link_node_ref(struct jffs2_sb_info *c,
586					       struct jffs2_eraseblock *jeb,
587					       uint32_t ofs, uint32_t len,
588					       struct jffs2_inode_cache *ic)
589{
590	struct jffs2_raw_node_ref *ref;
591
592	BUG_ON(!jeb->allocated_refs);
593	jeb->allocated_refs--;
594
595	ref = jeb->last_node;
596
597	dbg_noderef("Last node at %p is (%08x,%p)\n", ref, ref->flash_offset,
598		    ref->next_in_ino);
599
600	while (ref->flash_offset != REF_EMPTY_NODE) {
601		if (ref->flash_offset == REF_LINK_NODE)
602			ref = ref->next_in_ino;
603		else
604			ref++;
605	}
606
607	dbg_noderef("New ref is %p (%08x becomes %08x,%p) len 0x%x\n", ref,
608		    ref->flash_offset, ofs, ref->next_in_ino, len);
609
610	ref->flash_offset = ofs;
611
612	if (!jeb->first_node) {
613		jeb->first_node = ref;
614		BUG_ON(ref_offset(ref) != jeb->offset);
615	} else if (unlikely(ref_offset(ref) != jeb->offset + c->sector_size - jeb->free_size)) {
616		uint32_t last_len = ref_totlen(c, jeb, jeb->last_node);
617
618		JFFS2_ERROR("Adding new ref %p at (0x%08x-0x%08x) not immediately after previous (0x%08x-0x%08x)\n",
619			    ref, ref_offset(ref), ref_offset(ref)+len,
620			    ref_offset(jeb->last_node),
621			    ref_offset(jeb->last_node)+last_len);
622		BUG();
623	}
624	jeb->last_node = ref;
625
626	if (ic) {
627		ref->next_in_ino = ic->nodes;
628		ic->nodes = ref;
629	} else {
630		ref->next_in_ino = NULL;
631	}
632
633	switch(ref_flags(ref)) {
634	case REF_UNCHECKED:
635		c->unchecked_size += len;
636		jeb->unchecked_size += len;
637		break;
638
639	case REF_NORMAL:
640	case REF_PRISTINE:
641		c->used_size += len;
642		jeb->used_size += len;
643		break;
644
645	case REF_OBSOLETE:
646		c->dirty_size += len;
647		jeb->dirty_size += len;
648		break;
649	}
650	c->free_size -= len;
651	jeb->free_size -= len;
652
653#ifdef TEST_TOTLEN
654	/* Set (and test) __totlen field... for now */
655	ref->__totlen = len;
656	ref_totlen(c, jeb, ref);
657#endif
658	return ref;
659}
660
661/* No locking, no reservation of 'ref'. Do not use on a live file system */
662int jffs2_scan_dirty_space(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
663			   uint32_t size)
664{
665	if (!size)
666		return 0;
667	if (unlikely(size > jeb->free_size)) {
668		pr_crit("Dirty space 0x%x larger then free_size 0x%x (wasted 0x%x)\n",
669			size, jeb->free_size, jeb->wasted_size);
670		BUG();
671	}
672	/* REF_EMPTY_NODE is !obsolete, so that works OK */
673	if (jeb->last_node && ref_obsolete(jeb->last_node)) {
674#ifdef TEST_TOTLEN
675		jeb->last_node->__totlen += size;
676#endif
677		c->dirty_size += size;
678		c->free_size -= size;
679		jeb->dirty_size += size;
680		jeb->free_size -= size;
681	} else {
682		uint32_t ofs = jeb->offset + c->sector_size - jeb->free_size;
683		ofs |= REF_OBSOLETE;
684
685		jffs2_link_node_ref(c, jeb, ofs, size, NULL);
686	}
687
688	return 0;
689}
690
691/* Calculate totlen from surrounding nodes or eraseblock */
692static inline uint32_t __ref_totlen(struct jffs2_sb_info *c,
693				    struct jffs2_eraseblock *jeb,
694				    struct jffs2_raw_node_ref *ref)
695{
696	uint32_t ref_end;
697	struct jffs2_raw_node_ref *next_ref = ref_next(ref);
698
699	if (next_ref)
700		ref_end = ref_offset(next_ref);
701	else {
702		if (!jeb)
703			jeb = &c->blocks[ref->flash_offset / c->sector_size];
704
705		/* Last node in block. Use free_space */
706		if (unlikely(ref != jeb->last_node)) {
707			pr_crit("ref %p @0x%08x is not jeb->last_node (%p @0x%08x)\n",
708				ref, ref_offset(ref), jeb->last_node,
709				jeb->last_node ?
710				ref_offset(jeb->last_node) : 0);
711			BUG();
712		}
713		ref_end = jeb->offset + c->sector_size - jeb->free_size;
714	}
715	return ref_end - ref_offset(ref);
716}
717
718uint32_t __jffs2_ref_totlen(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
719			    struct jffs2_raw_node_ref *ref)
720{
721	uint32_t ret;
722
723	ret = __ref_totlen(c, jeb, ref);
724
725#ifdef TEST_TOTLEN
726	if (unlikely(ret != ref->__totlen)) {
727		if (!jeb)
728			jeb = &c->blocks[ref->flash_offset / c->sector_size];
729
730		pr_crit("Totlen for ref at %p (0x%08x-0x%08x) miscalculated as 0x%x instead of %x\n",
731			ref, ref_offset(ref), ref_offset(ref) + ref->__totlen,
732			ret, ref->__totlen);
733		if (ref_next(ref)) {
734			pr_crit("next %p (0x%08x-0x%08x)\n",
735				ref_next(ref), ref_offset(ref_next(ref)),
736				ref_offset(ref_next(ref)) + ref->__totlen);
737		} else
738			pr_crit("No next ref. jeb->last_node is %p\n",
739				jeb->last_node);
740
741		pr_crit("jeb->wasted_size %x, dirty_size %x, used_size %x, free_size %x\n",
742			jeb->wasted_size, jeb->dirty_size, jeb->used_size,
743			jeb->free_size);
744
745#if defined(JFFS2_DBG_DUMPS) || defined(JFFS2_DBG_PARANOIA_CHECKS)
746		__jffs2_dbg_dump_node_refs_nolock(c, jeb);
747#endif
748
749		WARN_ON(1);
750
751		ret = ref->__totlen;
752	}
753#endif /* TEST_TOTLEN */
754	return ret;
755}
756