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v3.1
  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/mtd/mtd.h>
 14#include <linux/compiler.h>
 15#include <linux/sched.h> /* For cond_resched() */
 16#include "nodelist.h"
 17#include "debug.h"
 18
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 19/**
 20 *	jffs2_reserve_space - request physical space to write nodes to flash
 21 *	@c: superblock info
 22 *	@minsize: Minimum acceptable size of allocation
 23 *	@len: Returned value of allocation length
 24 *	@prio: Allocation type - ALLOC_{NORMAL,DELETION}
 25 *
 26 *	Requests a block of physical space on the flash. Returns zero for success
 27 *	and puts 'len' into the appropriate place, or returns -ENOSPC or other 
 28 *	error if appropriate. Doesn't return len since that's 
 29 *
 30 *	If it returns zero, jffs2_reserve_space() also downs the per-filesystem
 31 *	allocation semaphore, to prevent more than one allocation from being
 32 *	active at any time. The semaphore is later released by jffs2_commit_allocation()
 33 *
 34 *	jffs2_reserve_space() may trigger garbage collection in order to make room
 35 *	for the requested allocation.
 36 */
 37
 38static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize,
 39				  uint32_t *len, uint32_t sumsize);
 40
 41int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 42			uint32_t *len, int prio, uint32_t sumsize)
 43{
 44	int ret = -EAGAIN;
 45	int blocksneeded = c->resv_blocks_write;
 46	/* align it */
 47	minsize = PAD(minsize);
 48
 49	D1(printk(KERN_DEBUG "jffs2_reserve_space(): Requested 0x%x bytes\n", minsize));
 50	mutex_lock(&c->alloc_sem);
 51
 52	D1(printk(KERN_DEBUG "jffs2_reserve_space(): alloc sem got\n"));
 53
 54	spin_lock(&c->erase_completion_lock);
 55
 
 
 
 
 
 
 
 
 
 56	/* this needs a little more thought (true <tglx> :)) */
 57	while(ret == -EAGAIN) {
 58		while(c->nr_free_blocks + c->nr_erasing_blocks < blocksneeded) {
 59			uint32_t dirty, avail;
 60
 61			/* calculate real dirty size
 62			 * dirty_size contains blocks on erase_pending_list
 63			 * those blocks are counted in c->nr_erasing_blocks.
 64			 * If one block is actually erased, it is not longer counted as dirty_space
 65			 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
 66			 * with c->nr_erasing_blocks * c->sector_size again.
 67			 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
 68			 * This helps us to force gc and pick eventually a clean block to spread the load.
 69			 * We add unchecked_size here, as we hopefully will find some space to use.
 70			 * This will affect the sum only once, as gc first finishes checking
 71			 * of nodes.
 72			 */
 73			dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size + c->unchecked_size;
 74			if (dirty < c->nospc_dirty_size) {
 75				if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
 76					D1(printk(KERN_NOTICE "jffs2_reserve_space(): Low on dirty space to GC, but it's a deletion. Allowing...\n"));
 
 77					break;
 78				}
 79				D1(printk(KERN_DEBUG "dirty size 0x%08x + unchecked_size 0x%08x < nospc_dirty_size 0x%08x, returning -ENOSPC\n",
 80					  dirty, c->unchecked_size, c->sector_size));
 
 81
 82				spin_unlock(&c->erase_completion_lock);
 83				mutex_unlock(&c->alloc_sem);
 84				return -ENOSPC;
 85			}
 86
 87			/* Calc possibly available space. Possibly available means that we
 88			 * don't know, if unchecked size contains obsoleted nodes, which could give us some
 89			 * more usable space. This will affect the sum only once, as gc first finishes checking
 90			 * of nodes.
 91			 + Return -ENOSPC, if the maximum possibly available space is less or equal than
 92			 * blocksneeded * sector_size.
 93			 * This blocks endless gc looping on a filesystem, which is nearly full, even if
 94			 * the check above passes.
 95			 */
 96			avail = c->free_size + c->dirty_size + c->erasing_size + c->unchecked_size;
 97			if ( (avail / c->sector_size) <= blocksneeded) {
 98				if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
 99					D1(printk(KERN_NOTICE "jffs2_reserve_space(): Low on possibly available space, but it's a deletion. Allowing...\n"));
 
100					break;
101				}
102
103				D1(printk(KERN_DEBUG "max. available size 0x%08x  < blocksneeded * sector_size 0x%08x, returning -ENOSPC\n",
104					  avail, blocksneeded * c->sector_size));
105				spin_unlock(&c->erase_completion_lock);
106				mutex_unlock(&c->alloc_sem);
107				return -ENOSPC;
108			}
109
110			mutex_unlock(&c->alloc_sem);
111
112			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",
113				  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,
114				  c->free_size + c->dirty_size + c->wasted_size + c->used_size + c->erasing_size + c->bad_size, c->flash_size));
 
 
 
 
 
115			spin_unlock(&c->erase_completion_lock);
116
117			ret = jffs2_garbage_collect_pass(c);
118
119			if (ret == -EAGAIN) {
120				spin_lock(&c->erase_completion_lock);
121				if (c->nr_erasing_blocks &&
122				    list_empty(&c->erase_pending_list) &&
123				    list_empty(&c->erase_complete_list)) {
124					DECLARE_WAITQUEUE(wait, current);
125					set_current_state(TASK_UNINTERRUPTIBLE);
126					add_wait_queue(&c->erase_wait, &wait);
127					D1(printk(KERN_DEBUG "%s waiting for erase to complete\n", __func__));
 
128					spin_unlock(&c->erase_completion_lock);
129
130					schedule();
131				} else
132					spin_unlock(&c->erase_completion_lock);
133			} else if (ret)
134				return ret;
135
136			cond_resched();
137
138			if (signal_pending(current))
139				return -EINTR;
140
141			mutex_lock(&c->alloc_sem);
142			spin_lock(&c->erase_completion_lock);
143		}
144
145		ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
146		if (ret) {
147			D1(printk(KERN_DEBUG "jffs2_reserve_space: ret is %d\n", ret));
148		}
149	}
 
 
150	spin_unlock(&c->erase_completion_lock);
151	if (!ret)
152		ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
153	if (ret)
154		mutex_unlock(&c->alloc_sem);
155	return ret;
156}
157
158int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
159			   uint32_t *len, uint32_t sumsize)
160{
161	int ret = -EAGAIN;
162	minsize = PAD(minsize);
163
164	D1(printk(KERN_DEBUG "jffs2_reserve_space_gc(): Requested 0x%x bytes\n", minsize));
165
166	spin_lock(&c->erase_completion_lock);
167	while(ret == -EAGAIN) {
168		ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
169		if (ret) {
170			D1(printk(KERN_DEBUG "jffs2_reserve_space_gc: looping, ret is %d\n", ret));
 
171		}
172	}
173	spin_unlock(&c->erase_completion_lock);
174	if (!ret)
175		ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
176
177	return ret;
178}
179
180
181/* Classify nextblock (clean, dirty of verydirty) and force to select an other one */
182
183static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
184{
185
186	if (c->nextblock == NULL) {
187		D1(printk(KERN_DEBUG "jffs2_close_nextblock: Erase block at 0x%08x has already been placed in a list\n",
188		  jeb->offset));
189		return;
190	}
191	/* Check, if we have a dirty block now, or if it was dirty already */
192	if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
193		c->dirty_size += jeb->wasted_size;
194		c->wasted_size -= jeb->wasted_size;
195		jeb->dirty_size += jeb->wasted_size;
196		jeb->wasted_size = 0;
197		if (VERYDIRTY(c, jeb->dirty_size)) {
198			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",
199			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 
200			list_add_tail(&jeb->list, &c->very_dirty_list);
201		} else {
202			D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
203			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 
204			list_add_tail(&jeb->list, &c->dirty_list);
205		}
206	} else {
207		D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
208		  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 
209		list_add_tail(&jeb->list, &c->clean_list);
210	}
211	c->nextblock = NULL;
212
213}
214
215/* Select a new jeb for nextblock */
216
217static int jffs2_find_nextblock(struct jffs2_sb_info *c)
218{
219	struct list_head *next;
220
221	/* Take the next block off the 'free' list */
222
223	if (list_empty(&c->free_list)) {
224
225		if (!c->nr_erasing_blocks &&
226			!list_empty(&c->erasable_list)) {
227			struct jffs2_eraseblock *ejeb;
228
229			ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
230			list_move_tail(&ejeb->list, &c->erase_pending_list);
231			c->nr_erasing_blocks++;
232			jffs2_garbage_collect_trigger(c);
233			D1(printk(KERN_DEBUG "jffs2_find_nextblock: Triggering erase of erasable block at 0x%08x\n",
234				  ejeb->offset));
235		}
236
237		if (!c->nr_erasing_blocks &&
238			!list_empty(&c->erasable_pending_wbuf_list)) {
239			D1(printk(KERN_DEBUG "jffs2_find_nextblock: Flushing write buffer\n"));
 
240			/* c->nextblock is NULL, no update to c->nextblock allowed */
241			spin_unlock(&c->erase_completion_lock);
242			jffs2_flush_wbuf_pad(c);
243			spin_lock(&c->erase_completion_lock);
244			/* Have another go. It'll be on the erasable_list now */
245			return -EAGAIN;
246		}
247
248		if (!c->nr_erasing_blocks) {
249			/* Ouch. We're in GC, or we wouldn't have got here.
250			   And there's no space left. At all. */
251			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",
252				   c->nr_erasing_blocks, c->nr_free_blocks, list_empty(&c->erasable_list)?"yes":"no",
253				   list_empty(&c->erasing_list)?"yes":"no", list_empty(&c->erase_pending_list)?"yes":"no");
 
 
254			return -ENOSPC;
255		}
256
257		spin_unlock(&c->erase_completion_lock);
258		/* Don't wait for it; just erase one right now */
259		jffs2_erase_pending_blocks(c, 1);
260		spin_lock(&c->erase_completion_lock);
261
262		/* An erase may have failed, decreasing the
263		   amount of free space available. So we must
264		   restart from the beginning */
265		return -EAGAIN;
266	}
267
268	next = c->free_list.next;
269	list_del(next);
270	c->nextblock = list_entry(next, struct jffs2_eraseblock, list);
271	c->nr_free_blocks--;
272
273	jffs2_sum_reset_collected(c->summary); /* reset collected summary */
274
275#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
276	/* adjust write buffer offset, else we get a non contiguous write bug */
277	if (!(c->wbuf_ofs % c->sector_size) && !c->wbuf_len)
278		c->wbuf_ofs = 0xffffffff;
279#endif
280
281	D1(printk(KERN_DEBUG "jffs2_find_nextblock(): new nextblock = 0x%08x\n", c->nextblock->offset));
 
282
283	return 0;
284}
285
286/* Called with alloc sem _and_ erase_completion_lock */
287static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
288				  uint32_t *len, uint32_t sumsize)
289{
290	struct jffs2_eraseblock *jeb = c->nextblock;
291	uint32_t reserved_size;				/* for summary information at the end of the jeb */
292	int ret;
293
294 restart:
295	reserved_size = 0;
296
297	if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) {
298							/* NOSUM_SIZE means not to generate summary */
299
300		if (jeb) {
301			reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
302			dbg_summary("minsize=%d , jeb->free=%d ,"
303						"summary->size=%d , sumsize=%d\n",
304						minsize, jeb->free_size,
305						c->summary->sum_size, sumsize);
306		}
307
308		/* Is there enough space for writing out the current node, or we have to
309		   write out summary information now, close this jeb and select new nextblock? */
310		if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize +
311					JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) {
312
313			/* Has summary been disabled for this jeb? */
314			if (jffs2_sum_is_disabled(c->summary)) {
315				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
316				goto restart;
317			}
318
319			/* Writing out the collected summary information */
320			dbg_summary("generating summary for 0x%08x.\n", jeb->offset);
321			ret = jffs2_sum_write_sumnode(c);
322
323			if (ret)
324				return ret;
325
326			if (jffs2_sum_is_disabled(c->summary)) {
327				/* jffs2_write_sumnode() couldn't write out the summary information
328				   diabling summary for this jeb and free the collected information
329				 */
330				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
331				goto restart;
332			}
333
334			jffs2_close_nextblock(c, jeb);
335			jeb = NULL;
336			/* keep always valid value in reserved_size */
337			reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
338		}
339	} else {
340		if (jeb && minsize > jeb->free_size) {
341			uint32_t waste;
342
343			/* Skip the end of this block and file it as having some dirty space */
344			/* If there's a pending write to it, flush now */
345
346			if (jffs2_wbuf_dirty(c)) {
347				spin_unlock(&c->erase_completion_lock);
348				D1(printk(KERN_DEBUG "jffs2_do_reserve_space: Flushing write buffer\n"));
 
349				jffs2_flush_wbuf_pad(c);
350				spin_lock(&c->erase_completion_lock);
351				jeb = c->nextblock;
352				goto restart;
353			}
354
355			spin_unlock(&c->erase_completion_lock);
356
357			ret = jffs2_prealloc_raw_node_refs(c, jeb, 1);
358			if (ret)
359				return ret;
360			/* Just lock it again and continue. Nothing much can change because
361			   we hold c->alloc_sem anyway. In fact, it's not entirely clear why
362			   we hold c->erase_completion_lock in the majority of this function...
363			   but that's a question for another (more caffeine-rich) day. */
364			spin_lock(&c->erase_completion_lock);
365
366			waste = jeb->free_size;
367			jffs2_link_node_ref(c, jeb,
368					    (jeb->offset + c->sector_size - waste) | REF_OBSOLETE,
369					    waste, NULL);
370			/* FIXME: that made it count as dirty. Convert to wasted */
371			jeb->dirty_size -= waste;
372			c->dirty_size -= waste;
373			jeb->wasted_size += waste;
374			c->wasted_size += waste;
375
376			jffs2_close_nextblock(c, jeb);
377			jeb = NULL;
378		}
379	}
380
381	if (!jeb) {
382
383		ret = jffs2_find_nextblock(c);
384		if (ret)
385			return ret;
386
387		jeb = c->nextblock;
388
389		if (jeb->free_size != c->sector_size - c->cleanmarker_size) {
390			printk(KERN_WARNING "Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n", jeb->offset, jeb->free_size);
 
391			goto restart;
392		}
393	}
394	/* OK, jeb (==c->nextblock) is now pointing at a block which definitely has
395	   enough space */
396	*len = jeb->free_size - reserved_size;
397
398	if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size &&
399	    !jeb->first_node->next_in_ino) {
400		/* Only node in it beforehand was a CLEANMARKER node (we think).
401		   So mark it obsolete now that there's going to be another node
402		   in the block. This will reduce used_size to zero but We've
403		   already set c->nextblock so that jffs2_mark_node_obsolete()
404		   won't try to refile it to the dirty_list.
405		*/
406		spin_unlock(&c->erase_completion_lock);
407		jffs2_mark_node_obsolete(c, jeb->first_node);
408		spin_lock(&c->erase_completion_lock);
409	}
410
411	D1(printk(KERN_DEBUG "jffs2_do_reserve_space(): Giving 0x%x bytes at 0x%x\n",
412		  *len, jeb->offset + (c->sector_size - jeb->free_size)));
 
413	return 0;
414}
415
416/**
417 *	jffs2_add_physical_node_ref - add a physical node reference to the list
418 *	@c: superblock info
419 *	@new: new node reference to add
420 *	@len: length of this physical node
421 *
422 *	Should only be used to report nodes for which space has been allocated
423 *	by jffs2_reserve_space.
424 *
425 *	Must be called with the alloc_sem held.
426 */
427
428struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
429						       uint32_t ofs, uint32_t len,
430						       struct jffs2_inode_cache *ic)
431{
432	struct jffs2_eraseblock *jeb;
433	struct jffs2_raw_node_ref *new;
434
435	jeb = &c->blocks[ofs / c->sector_size];
436
437	D1(printk(KERN_DEBUG "jffs2_add_physical_node_ref(): Node at 0x%x(%d), size 0x%x\n",
438		  ofs & ~3, ofs & 3, len));
439#if 1
440	/* Allow non-obsolete nodes only to be added at the end of c->nextblock, 
441	   if c->nextblock is set. Note that wbuf.c will file obsolete nodes
442	   even after refiling c->nextblock */
443	if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE))
444	    && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) {
445		printk(KERN_WARNING "argh. node added in wrong place at 0x%08x(%d)\n", ofs & ~3, ofs & 3);
 
446		if (c->nextblock)
447			printk(KERN_WARNING "nextblock 0x%08x", c->nextblock->offset);
448		else
449			printk(KERN_WARNING "No nextblock");
450		printk(", expected at %08x\n", jeb->offset + (c->sector_size - jeb->free_size));
 
451		return ERR_PTR(-EINVAL);
452	}
453#endif
454	spin_lock(&c->erase_completion_lock);
455
456	new = jffs2_link_node_ref(c, jeb, ofs, len, ic);
457
458	if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) {
459		/* If it lives on the dirty_list, jffs2_reserve_space will put it there */
460		D1(printk(KERN_DEBUG "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
461			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 
462		if (jffs2_wbuf_dirty(c)) {
463			/* Flush the last write in the block if it's outstanding */
464			spin_unlock(&c->erase_completion_lock);
465			jffs2_flush_wbuf_pad(c);
466			spin_lock(&c->erase_completion_lock);
467		}
468
469		list_add_tail(&jeb->list, &c->clean_list);
470		c->nextblock = NULL;
471	}
472	jffs2_dbg_acct_sanity_check_nolock(c,jeb);
473	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
474
475	spin_unlock(&c->erase_completion_lock);
476
477	return new;
478}
479
480
481void jffs2_complete_reservation(struct jffs2_sb_info *c)
482{
483	D1(printk(KERN_DEBUG "jffs2_complete_reservation()\n"));
484	spin_lock(&c->erase_completion_lock);
485	jffs2_garbage_collect_trigger(c);
486	spin_unlock(&c->erase_completion_lock);
487	mutex_unlock(&c->alloc_sem);
488}
489
490static inline int on_list(struct list_head *obj, struct list_head *head)
491{
492	struct list_head *this;
493
494	list_for_each(this, head) {
495		if (this == obj) {
496			D1(printk("%p is on list at %p\n", obj, head));
497			return 1;
498
499		}
500	}
501	return 0;
502}
503
504void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref)
505{
506	struct jffs2_eraseblock *jeb;
507	int blocknr;
508	struct jffs2_unknown_node n;
509	int ret, addedsize;
510	size_t retlen;
511	uint32_t freed_len;
512
513	if(unlikely(!ref)) {
514		printk(KERN_NOTICE "EEEEEK. jffs2_mark_node_obsolete called with NULL node\n");
515		return;
516	}
517	if (ref_obsolete(ref)) {
518		D1(printk(KERN_DEBUG "jffs2_mark_node_obsolete called with already obsolete node at 0x%08x\n", ref_offset(ref)));
 
519		return;
520	}
521	blocknr = ref->flash_offset / c->sector_size;
522	if (blocknr >= c->nr_blocks) {
523		printk(KERN_NOTICE "raw node at 0x%08x is off the end of device!\n", ref->flash_offset);
 
524		BUG();
525	}
526	jeb = &c->blocks[blocknr];
527
528	if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) &&
529	    !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) {
530		/* Hm. This may confuse static lock analysis. If any of the above
531		   three conditions is false, we're going to return from this
532		   function without actually obliterating any nodes or freeing
533		   any jffs2_raw_node_refs. So we don't need to stop erases from
534		   happening, or protect against people holding an obsolete
535		   jffs2_raw_node_ref without the erase_completion_lock. */
536		mutex_lock(&c->erase_free_sem);
537	}
538
539	spin_lock(&c->erase_completion_lock);
540
541	freed_len = ref_totlen(c, jeb, ref);
542
543	if (ref_flags(ref) == REF_UNCHECKED) {
544		D1(if (unlikely(jeb->unchecked_size < freed_len)) {
545			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",
546			       freed_len, blocknr, ref->flash_offset, jeb->used_size);
 
547			BUG();
548		})
549		D1(printk(KERN_DEBUG "Obsoleting previously unchecked node at 0x%08x of len %x: ", ref_offset(ref), freed_len));
 
550		jeb->unchecked_size -= freed_len;
551		c->unchecked_size -= freed_len;
552	} else {
553		D1(if (unlikely(jeb->used_size < freed_len)) {
554			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",
555			       freed_len, blocknr, ref->flash_offset, jeb->used_size);
 
556			BUG();
557		})
558		D1(printk(KERN_DEBUG "Obsoleting node at 0x%08x of len %#x: ", ref_offset(ref), freed_len));
 
559		jeb->used_size -= freed_len;
560		c->used_size -= freed_len;
561	}
562
563	// Take care, that wasted size is taken into concern
564	if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) {
565		D1(printk("Dirtying\n"));
566		addedsize = freed_len;
567		jeb->dirty_size += freed_len;
568		c->dirty_size += freed_len;
569
570		/* Convert wasted space to dirty, if not a bad block */
571		if (jeb->wasted_size) {
572			if (on_list(&jeb->list, &c->bad_used_list)) {
573				D1(printk(KERN_DEBUG "Leaving block at %08x on the bad_used_list\n",
574					  jeb->offset));
575				addedsize = 0; /* To fool the refiling code later */
576			} else {
577				D1(printk(KERN_DEBUG "Converting %d bytes of wasted space to dirty in block at %08x\n",
578					  jeb->wasted_size, jeb->offset));
579				addedsize += jeb->wasted_size;
580				jeb->dirty_size += jeb->wasted_size;
581				c->dirty_size += jeb->wasted_size;
582				c->wasted_size -= jeb->wasted_size;
583				jeb->wasted_size = 0;
584			}
585		}
586	} else {
587		D1(printk("Wasting\n"));
588		addedsize = 0;
589		jeb->wasted_size += freed_len;
590		c->wasted_size += freed_len;
591	}
592	ref->flash_offset = ref_offset(ref) | REF_OBSOLETE;
593
594	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
595	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
596
597	if (c->flags & JFFS2_SB_FLAG_SCANNING) {
598		/* Flash scanning is in progress. Don't muck about with the block
599		   lists because they're not ready yet, and don't actually
600		   obliterate nodes that look obsolete. If they weren't
601		   marked obsolete on the flash at the time they _became_
602		   obsolete, there was probably a reason for that. */
603		spin_unlock(&c->erase_completion_lock);
604		/* We didn't lock the erase_free_sem */
605		return;
606	}
607
608	if (jeb == c->nextblock) {
609		D2(printk(KERN_DEBUG "Not moving nextblock 0x%08x to dirty/erase_pending list\n", jeb->offset));
 
610	} else if (!jeb->used_size && !jeb->unchecked_size) {
611		if (jeb == c->gcblock) {
612			D1(printk(KERN_DEBUG "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n", jeb->offset));
 
613			c->gcblock = NULL;
614		} else {
615			D1(printk(KERN_DEBUG "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n", jeb->offset));
 
616			list_del(&jeb->list);
617		}
618		if (jffs2_wbuf_dirty(c)) {
619			D1(printk(KERN_DEBUG "...and adding to erasable_pending_wbuf_list\n"));
620			list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list);
621		} else {
622			if (jiffies & 127) {
623				/* Most of the time, we just erase it immediately. Otherwise we
624				   spend ages scanning it on mount, etc. */
625				D1(printk(KERN_DEBUG "...and adding to erase_pending_list\n"));
626				list_add_tail(&jeb->list, &c->erase_pending_list);
627				c->nr_erasing_blocks++;
628				jffs2_garbage_collect_trigger(c);
629			} else {
630				/* Sometimes, however, we leave it elsewhere so it doesn't get
631				   immediately reused, and we spread the load a bit. */
632				D1(printk(KERN_DEBUG "...and adding to erasable_list\n"));
633				list_add_tail(&jeb->list, &c->erasable_list);
634			}
635		}
636		D1(printk(KERN_DEBUG "Done OK\n"));
637	} else if (jeb == c->gcblock) {
638		D2(printk(KERN_DEBUG "Not moving gcblock 0x%08x to dirty_list\n", jeb->offset));
 
639	} else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) {
640		D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n", jeb->offset));
 
641		list_del(&jeb->list);
642		D1(printk(KERN_DEBUG "...and adding to dirty_list\n"));
643		list_add_tail(&jeb->list, &c->dirty_list);
644	} else if (VERYDIRTY(c, jeb->dirty_size) &&
645		   !VERYDIRTY(c, jeb->dirty_size - addedsize)) {
646		D1(printk(KERN_DEBUG "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n", jeb->offset));
 
647		list_del(&jeb->list);
648		D1(printk(KERN_DEBUG "...and adding to very_dirty_list\n"));
649		list_add_tail(&jeb->list, &c->very_dirty_list);
650	} else {
651		D1(printk(KERN_DEBUG "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n",
652			  jeb->offset, jeb->free_size, jeb->dirty_size, jeb->used_size));
 
653	}
654
655	spin_unlock(&c->erase_completion_lock);
656
657	if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) ||
658		(c->flags & JFFS2_SB_FLAG_BUILDING)) {
659		/* We didn't lock the erase_free_sem */
660		return;
661	}
662
663	/* The erase_free_sem is locked, and has been since before we marked the node obsolete
664	   and potentially put its eraseblock onto the erase_pending_list. Thus, we know that
665	   the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet
666	   by jffs2_free_jeb_node_refs() in erase.c. Which is nice. */
667
668	D1(printk(KERN_DEBUG "obliterating obsoleted node at 0x%08x\n", ref_offset(ref)));
 
669	ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
670	if (ret) {
671		printk(KERN_WARNING "Read error reading from obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
 
672		goto out_erase_sem;
673	}
674	if (retlen != sizeof(n)) {
675		printk(KERN_WARNING "Short read from obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
 
676		goto out_erase_sem;
677	}
678	if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) {
679		printk(KERN_WARNING "Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n", je32_to_cpu(n.totlen), freed_len);
 
680		goto out_erase_sem;
681	}
682	if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) {
683		D1(printk(KERN_DEBUG "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n", ref_offset(ref), je16_to_cpu(n.nodetype)));
 
684		goto out_erase_sem;
685	}
686	/* XXX FIXME: This is ugly now */
687	n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE);
688	ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
689	if (ret) {
690		printk(KERN_WARNING "Write error in obliterating obsoleted node at 0x%08x: %d\n", ref_offset(ref), ret);
 
691		goto out_erase_sem;
692	}
693	if (retlen != sizeof(n)) {
694		printk(KERN_WARNING "Short write in obliterating obsoleted node at 0x%08x: %zd\n", ref_offset(ref), retlen);
 
695		goto out_erase_sem;
696	}
697
698	/* Nodes which have been marked obsolete no longer need to be
699	   associated with any inode. Remove them from the per-inode list.
700
701	   Note we can't do this for NAND at the moment because we need
702	   obsolete dirent nodes to stay on the lists, because of the
703	   horridness in jffs2_garbage_collect_deletion_dirent(). Also
704	   because we delete the inocache, and on NAND we need that to
705	   stay around until all the nodes are actually erased, in order
706	   to stop us from giving the same inode number to another newly
707	   created inode. */
708	if (ref->next_in_ino) {
709		struct jffs2_inode_cache *ic;
710		struct jffs2_raw_node_ref **p;
711
712		spin_lock(&c->erase_completion_lock);
713
714		ic = jffs2_raw_ref_to_ic(ref);
715		for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino))
716			;
717
718		*p = ref->next_in_ino;
719		ref->next_in_ino = NULL;
720
721		switch (ic->class) {
722#ifdef CONFIG_JFFS2_FS_XATTR
723			case RAWNODE_CLASS_XATTR_DATUM:
724				jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
725				break;
726			case RAWNODE_CLASS_XATTR_REF:
727				jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
728				break;
729#endif
730			default:
731				if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
732					jffs2_del_ino_cache(c, ic);
733				break;
734		}
735		spin_unlock(&c->erase_completion_lock);
736	}
737
738 out_erase_sem:
739	mutex_unlock(&c->erase_free_sem);
740}
741
742int jffs2_thread_should_wake(struct jffs2_sb_info *c)
743{
744	int ret = 0;
745	uint32_t dirty;
746	int nr_very_dirty = 0;
747	struct jffs2_eraseblock *jeb;
748
749	if (!list_empty(&c->erase_complete_list) ||
750	    !list_empty(&c->erase_pending_list))
751		return 1;
752
753	if (c->unchecked_size) {
754		D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): unchecked_size %d, checked_ino #%d\n",
755			  c->unchecked_size, c->checked_ino));
756		return 1;
757	}
758
759	/* dirty_size contains blocks on erase_pending_list
760	 * those blocks are counted in c->nr_erasing_blocks.
761	 * If one block is actually erased, it is not longer counted as dirty_space
762	 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
763	 * with c->nr_erasing_blocks * c->sector_size again.
764	 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
765	 * This helps us to force gc and pick eventually a clean block to spread the load.
766	 */
767	dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size;
768
769	if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger &&
770			(dirty > c->nospc_dirty_size))
771		ret = 1;
772
773	list_for_each_entry(jeb, &c->very_dirty_list, list) {
774		nr_very_dirty++;
775		if (nr_very_dirty == c->vdirty_blocks_gctrigger) {
776			ret = 1;
777			/* In debug mode, actually go through and count them all */
778			D1(continue);
779			break;
780		}
781	}
782
783	D1(printk(KERN_DEBUG "jffs2_thread_should_wake(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x, vdirty_blocks %d: %s\n",
784		  c->nr_free_blocks, c->nr_erasing_blocks, c->dirty_size, nr_very_dirty, ret?"yes":"no"));
 
785
786	return ret;
787}
v3.5.6
  1/*
  2 * JFFS2 -- Journalling Flash File System, Version 2.
  3 *
  4 * Copyright © 2001-2007 Red Hat, Inc.
  5 *
  6 * Created by David Woodhouse <dwmw2@infradead.org>
  7 *
  8 * For licensing information, see the file 'LICENCE' in this directory.
  9 *
 10 */
 11
 12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 13
 14#include <linux/kernel.h>
 15#include <linux/mtd/mtd.h>
 16#include <linux/compiler.h>
 17#include <linux/sched.h> /* For cond_resched() */
 18#include "nodelist.h"
 19#include "debug.h"
 20
 21/*
 22 * Check whether the user is allowed to write.
 23 */
 24static int jffs2_rp_can_write(struct jffs2_sb_info *c)
 25{
 26	uint32_t avail;
 27	struct jffs2_mount_opts *opts = &c->mount_opts;
 28
 29	avail = c->dirty_size + c->free_size + c->unchecked_size +
 30		c->erasing_size - c->resv_blocks_write * c->sector_size
 31		- c->nospc_dirty_size;
 32
 33	if (avail < 2 * opts->rp_size)
 34		jffs2_dbg(1, "rpsize %u, dirty_size %u, free_size %u, "
 35			  "erasing_size %u, unchecked_size %u, "
 36			  "nr_erasing_blocks %u, avail %u, resrv %u\n",
 37			  opts->rp_size, c->dirty_size, c->free_size,
 38			  c->erasing_size, c->unchecked_size,
 39			  c->nr_erasing_blocks, avail, c->nospc_dirty_size);
 40
 41	if (avail > opts->rp_size)
 42		return 1;
 43
 44	/* Always allow root */
 45	if (capable(CAP_SYS_RESOURCE))
 46		return 1;
 47
 48	jffs2_dbg(1, "forbid writing\n");
 49	return 0;
 50}
 51
 52/**
 53 *	jffs2_reserve_space - request physical space to write nodes to flash
 54 *	@c: superblock info
 55 *	@minsize: Minimum acceptable size of allocation
 56 *	@len: Returned value of allocation length
 57 *	@prio: Allocation type - ALLOC_{NORMAL,DELETION}
 58 *
 59 *	Requests a block of physical space on the flash. Returns zero for success
 60 *	and puts 'len' into the appropriate place, or returns -ENOSPC or other 
 61 *	error if appropriate. Doesn't return len since that's 
 62 *
 63 *	If it returns zero, jffs2_reserve_space() also downs the per-filesystem
 64 *	allocation semaphore, to prevent more than one allocation from being
 65 *	active at any time. The semaphore is later released by jffs2_commit_allocation()
 66 *
 67 *	jffs2_reserve_space() may trigger garbage collection in order to make room
 68 *	for the requested allocation.
 69 */
 70
 71static int jffs2_do_reserve_space(struct jffs2_sb_info *c,  uint32_t minsize,
 72				  uint32_t *len, uint32_t sumsize);
 73
 74int jffs2_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
 75			uint32_t *len, int prio, uint32_t sumsize)
 76{
 77	int ret = -EAGAIN;
 78	int blocksneeded = c->resv_blocks_write;
 79	/* align it */
 80	minsize = PAD(minsize);
 81
 82	jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize);
 83	mutex_lock(&c->alloc_sem);
 84
 85	jffs2_dbg(1, "%s(): alloc sem got\n", __func__);
 86
 87	spin_lock(&c->erase_completion_lock);
 88
 89	/*
 90	 * Check if the free space is greater then size of the reserved pool.
 91	 * If not, only allow root to proceed with writing.
 92	 */
 93	if (prio != ALLOC_DELETION && !jffs2_rp_can_write(c)) {
 94		ret = -ENOSPC;
 95		goto out;
 96	}
 97
 98	/* this needs a little more thought (true <tglx> :)) */
 99	while(ret == -EAGAIN) {
100		while(c->nr_free_blocks + c->nr_erasing_blocks < blocksneeded) {
101			uint32_t dirty, avail;
102
103			/* calculate real dirty size
104			 * dirty_size contains blocks on erase_pending_list
105			 * those blocks are counted in c->nr_erasing_blocks.
106			 * If one block is actually erased, it is not longer counted as dirty_space
107			 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
108			 * with c->nr_erasing_blocks * c->sector_size again.
109			 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
110			 * This helps us to force gc and pick eventually a clean block to spread the load.
111			 * We add unchecked_size here, as we hopefully will find some space to use.
112			 * This will affect the sum only once, as gc first finishes checking
113			 * of nodes.
114			 */
115			dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size + c->unchecked_size;
116			if (dirty < c->nospc_dirty_size) {
117				if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
118					jffs2_dbg(1, "%s(): Low on dirty space to GC, but it's a deletion. Allowing...\n",
119						  __func__);
120					break;
121				}
122				jffs2_dbg(1, "dirty size 0x%08x + unchecked_size 0x%08x < nospc_dirty_size 0x%08x, returning -ENOSPC\n",
123					  dirty, c->unchecked_size,
124					  c->sector_size);
125
126				spin_unlock(&c->erase_completion_lock);
127				mutex_unlock(&c->alloc_sem);
128				return -ENOSPC;
129			}
130
131			/* Calc possibly available space. Possibly available means that we
132			 * don't know, if unchecked size contains obsoleted nodes, which could give us some
133			 * more usable space. This will affect the sum only once, as gc first finishes checking
134			 * of nodes.
135			 + Return -ENOSPC, if the maximum possibly available space is less or equal than
136			 * blocksneeded * sector_size.
137			 * This blocks endless gc looping on a filesystem, which is nearly full, even if
138			 * the check above passes.
139			 */
140			avail = c->free_size + c->dirty_size + c->erasing_size + c->unchecked_size;
141			if ( (avail / c->sector_size) <= blocksneeded) {
142				if (prio == ALLOC_DELETION && c->nr_free_blocks + c->nr_erasing_blocks >= c->resv_blocks_deletion) {
143					jffs2_dbg(1, "%s(): Low on possibly available space, but it's a deletion. Allowing...\n",
144						  __func__);
145					break;
146				}
147
148				jffs2_dbg(1, "max. available size 0x%08x  < blocksneeded * sector_size 0x%08x, returning -ENOSPC\n",
149					  avail, blocksneeded * c->sector_size);
150				spin_unlock(&c->erase_completion_lock);
151				mutex_unlock(&c->alloc_sem);
152				return -ENOSPC;
153			}
154
155			mutex_unlock(&c->alloc_sem);
156
157			jffs2_dbg(1, "Triggering GC pass. nr_free_blocks %d, nr_erasing_blocks %d, free_size 0x%08x, dirty_size 0x%08x, wasted_size 0x%08x, used_size 0x%08x, erasing_size 0x%08x, bad_size 0x%08x (total 0x%08x of 0x%08x)\n",
158				  c->nr_free_blocks, c->nr_erasing_blocks,
159				  c->free_size, c->dirty_size, c->wasted_size,
160				  c->used_size, c->erasing_size, c->bad_size,
161				  c->free_size + c->dirty_size +
162				  c->wasted_size + c->used_size +
163				  c->erasing_size + c->bad_size,
164				  c->flash_size);
165			spin_unlock(&c->erase_completion_lock);
166
167			ret = jffs2_garbage_collect_pass(c);
168
169			if (ret == -EAGAIN) {
170				spin_lock(&c->erase_completion_lock);
171				if (c->nr_erasing_blocks &&
172				    list_empty(&c->erase_pending_list) &&
173				    list_empty(&c->erase_complete_list)) {
174					DECLARE_WAITQUEUE(wait, current);
175					set_current_state(TASK_UNINTERRUPTIBLE);
176					add_wait_queue(&c->erase_wait, &wait);
177					jffs2_dbg(1, "%s waiting for erase to complete\n",
178						  __func__);
179					spin_unlock(&c->erase_completion_lock);
180
181					schedule();
182				} else
183					spin_unlock(&c->erase_completion_lock);
184			} else if (ret)
185				return ret;
186
187			cond_resched();
188
189			if (signal_pending(current))
190				return -EINTR;
191
192			mutex_lock(&c->alloc_sem);
193			spin_lock(&c->erase_completion_lock);
194		}
195
196		ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
197		if (ret) {
198			jffs2_dbg(1, "%s(): ret is %d\n", __func__, ret);
199		}
200	}
201
202out:
203	spin_unlock(&c->erase_completion_lock);
204	if (!ret)
205		ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
206	if (ret)
207		mutex_unlock(&c->alloc_sem);
208	return ret;
209}
210
211int jffs2_reserve_space_gc(struct jffs2_sb_info *c, uint32_t minsize,
212			   uint32_t *len, uint32_t sumsize)
213{
214	int ret = -EAGAIN;
215	minsize = PAD(minsize);
216
217	jffs2_dbg(1, "%s(): Requested 0x%x bytes\n", __func__, minsize);
218
219	spin_lock(&c->erase_completion_lock);
220	while(ret == -EAGAIN) {
221		ret = jffs2_do_reserve_space(c, minsize, len, sumsize);
222		if (ret) {
223			jffs2_dbg(1, "%s(): looping, ret is %d\n",
224				  __func__, ret);
225		}
226	}
227	spin_unlock(&c->erase_completion_lock);
228	if (!ret)
229		ret = jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
230
231	return ret;
232}
233
234
235/* Classify nextblock (clean, dirty of verydirty) and force to select an other one */
236
237static void jffs2_close_nextblock(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
238{
239
240	if (c->nextblock == NULL) {
241		jffs2_dbg(1, "%s(): Erase block at 0x%08x has already been placed in a list\n",
242			  __func__, jeb->offset);
243		return;
244	}
245	/* Check, if we have a dirty block now, or if it was dirty already */
246	if (ISDIRTY (jeb->wasted_size + jeb->dirty_size)) {
247		c->dirty_size += jeb->wasted_size;
248		c->wasted_size -= jeb->wasted_size;
249		jeb->dirty_size += jeb->wasted_size;
250		jeb->wasted_size = 0;
251		if (VERYDIRTY(c, jeb->dirty_size)) {
252			jffs2_dbg(1, "Adding full erase block at 0x%08x to very_dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
253				  jeb->offset, jeb->free_size, jeb->dirty_size,
254				  jeb->used_size);
255			list_add_tail(&jeb->list, &c->very_dirty_list);
256		} else {
257			jffs2_dbg(1, "Adding full erase block at 0x%08x to dirty_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
258				  jeb->offset, jeb->free_size, jeb->dirty_size,
259				  jeb->used_size);
260			list_add_tail(&jeb->list, &c->dirty_list);
261		}
262	} else {
263		jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
264			  jeb->offset, jeb->free_size, jeb->dirty_size,
265			  jeb->used_size);
266		list_add_tail(&jeb->list, &c->clean_list);
267	}
268	c->nextblock = NULL;
269
270}
271
272/* Select a new jeb for nextblock */
273
274static int jffs2_find_nextblock(struct jffs2_sb_info *c)
275{
276	struct list_head *next;
277
278	/* Take the next block off the 'free' list */
279
280	if (list_empty(&c->free_list)) {
281
282		if (!c->nr_erasing_blocks &&
283			!list_empty(&c->erasable_list)) {
284			struct jffs2_eraseblock *ejeb;
285
286			ejeb = list_entry(c->erasable_list.next, struct jffs2_eraseblock, list);
287			list_move_tail(&ejeb->list, &c->erase_pending_list);
288			c->nr_erasing_blocks++;
289			jffs2_garbage_collect_trigger(c);
290			jffs2_dbg(1, "%s(): Triggering erase of erasable block at 0x%08x\n",
291				  __func__, ejeb->offset);
292		}
293
294		if (!c->nr_erasing_blocks &&
295			!list_empty(&c->erasable_pending_wbuf_list)) {
296			jffs2_dbg(1, "%s(): Flushing write buffer\n",
297				  __func__);
298			/* c->nextblock is NULL, no update to c->nextblock allowed */
299			spin_unlock(&c->erase_completion_lock);
300			jffs2_flush_wbuf_pad(c);
301			spin_lock(&c->erase_completion_lock);
302			/* Have another go. It'll be on the erasable_list now */
303			return -EAGAIN;
304		}
305
306		if (!c->nr_erasing_blocks) {
307			/* Ouch. We're in GC, or we wouldn't have got here.
308			   And there's no space left. At all. */
309			pr_crit("Argh. No free space left for GC. nr_erasing_blocks is %d. nr_free_blocks is %d. (erasableempty: %s, erasingempty: %s, erasependingempty: %s)\n",
310				c->nr_erasing_blocks, c->nr_free_blocks,
311				list_empty(&c->erasable_list) ? "yes" : "no",
312				list_empty(&c->erasing_list) ? "yes" : "no",
313				list_empty(&c->erase_pending_list) ? "yes" : "no");
314			return -ENOSPC;
315		}
316
317		spin_unlock(&c->erase_completion_lock);
318		/* Don't wait for it; just erase one right now */
319		jffs2_erase_pending_blocks(c, 1);
320		spin_lock(&c->erase_completion_lock);
321
322		/* An erase may have failed, decreasing the
323		   amount of free space available. So we must
324		   restart from the beginning */
325		return -EAGAIN;
326	}
327
328	next = c->free_list.next;
329	list_del(next);
330	c->nextblock = list_entry(next, struct jffs2_eraseblock, list);
331	c->nr_free_blocks--;
332
333	jffs2_sum_reset_collected(c->summary); /* reset collected summary */
334
335#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
336	/* adjust write buffer offset, else we get a non contiguous write bug */
337	if (!(c->wbuf_ofs % c->sector_size) && !c->wbuf_len)
338		c->wbuf_ofs = 0xffffffff;
339#endif
340
341	jffs2_dbg(1, "%s(): new nextblock = 0x%08x\n",
342		  __func__, c->nextblock->offset);
343
344	return 0;
345}
346
347/* Called with alloc sem _and_ erase_completion_lock */
348static int jffs2_do_reserve_space(struct jffs2_sb_info *c, uint32_t minsize,
349				  uint32_t *len, uint32_t sumsize)
350{
351	struct jffs2_eraseblock *jeb = c->nextblock;
352	uint32_t reserved_size;				/* for summary information at the end of the jeb */
353	int ret;
354
355 restart:
356	reserved_size = 0;
357
358	if (jffs2_sum_active() && (sumsize != JFFS2_SUMMARY_NOSUM_SIZE)) {
359							/* NOSUM_SIZE means not to generate summary */
360
361		if (jeb) {
362			reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
363			dbg_summary("minsize=%d , jeb->free=%d ,"
364						"summary->size=%d , sumsize=%d\n",
365						minsize, jeb->free_size,
366						c->summary->sum_size, sumsize);
367		}
368
369		/* Is there enough space for writing out the current node, or we have to
370		   write out summary information now, close this jeb and select new nextblock? */
371		if (jeb && (PAD(minsize) + PAD(c->summary->sum_size + sumsize +
372					JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size)) {
373
374			/* Has summary been disabled for this jeb? */
375			if (jffs2_sum_is_disabled(c->summary)) {
376				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
377				goto restart;
378			}
379
380			/* Writing out the collected summary information */
381			dbg_summary("generating summary for 0x%08x.\n", jeb->offset);
382			ret = jffs2_sum_write_sumnode(c);
383
384			if (ret)
385				return ret;
386
387			if (jffs2_sum_is_disabled(c->summary)) {
388				/* jffs2_write_sumnode() couldn't write out the summary information
389				   diabling summary for this jeb and free the collected information
390				 */
391				sumsize = JFFS2_SUMMARY_NOSUM_SIZE;
392				goto restart;
393			}
394
395			jffs2_close_nextblock(c, jeb);
396			jeb = NULL;
397			/* keep always valid value in reserved_size */
398			reserved_size = PAD(sumsize + c->summary->sum_size + JFFS2_SUMMARY_FRAME_SIZE);
399		}
400	} else {
401		if (jeb && minsize > jeb->free_size) {
402			uint32_t waste;
403
404			/* Skip the end of this block and file it as having some dirty space */
405			/* If there's a pending write to it, flush now */
406
407			if (jffs2_wbuf_dirty(c)) {
408				spin_unlock(&c->erase_completion_lock);
409				jffs2_dbg(1, "%s(): Flushing write buffer\n",
410					  __func__);
411				jffs2_flush_wbuf_pad(c);
412				spin_lock(&c->erase_completion_lock);
413				jeb = c->nextblock;
414				goto restart;
415			}
416
417			spin_unlock(&c->erase_completion_lock);
418
419			ret = jffs2_prealloc_raw_node_refs(c, jeb, 1);
420			if (ret)
421				return ret;
422			/* Just lock it again and continue. Nothing much can change because
423			   we hold c->alloc_sem anyway. In fact, it's not entirely clear why
424			   we hold c->erase_completion_lock in the majority of this function...
425			   but that's a question for another (more caffeine-rich) day. */
426			spin_lock(&c->erase_completion_lock);
427
428			waste = jeb->free_size;
429			jffs2_link_node_ref(c, jeb,
430					    (jeb->offset + c->sector_size - waste) | REF_OBSOLETE,
431					    waste, NULL);
432			/* FIXME: that made it count as dirty. Convert to wasted */
433			jeb->dirty_size -= waste;
434			c->dirty_size -= waste;
435			jeb->wasted_size += waste;
436			c->wasted_size += waste;
437
438			jffs2_close_nextblock(c, jeb);
439			jeb = NULL;
440		}
441	}
442
443	if (!jeb) {
444
445		ret = jffs2_find_nextblock(c);
446		if (ret)
447			return ret;
448
449		jeb = c->nextblock;
450
451		if (jeb->free_size != c->sector_size - c->cleanmarker_size) {
452			pr_warn("Eep. Block 0x%08x taken from free_list had free_size of 0x%08x!!\n",
453				jeb->offset, jeb->free_size);
454			goto restart;
455		}
456	}
457	/* OK, jeb (==c->nextblock) is now pointing at a block which definitely has
458	   enough space */
459	*len = jeb->free_size - reserved_size;
460
461	if (c->cleanmarker_size && jeb->used_size == c->cleanmarker_size &&
462	    !jeb->first_node->next_in_ino) {
463		/* Only node in it beforehand was a CLEANMARKER node (we think).
464		   So mark it obsolete now that there's going to be another node
465		   in the block. This will reduce used_size to zero but We've
466		   already set c->nextblock so that jffs2_mark_node_obsolete()
467		   won't try to refile it to the dirty_list.
468		*/
469		spin_unlock(&c->erase_completion_lock);
470		jffs2_mark_node_obsolete(c, jeb->first_node);
471		spin_lock(&c->erase_completion_lock);
472	}
473
474	jffs2_dbg(1, "%s(): Giving 0x%x bytes at 0x%x\n",
475		  __func__,
476		  *len, jeb->offset + (c->sector_size - jeb->free_size));
477	return 0;
478}
479
480/**
481 *	jffs2_add_physical_node_ref - add a physical node reference to the list
482 *	@c: superblock info
483 *	@new: new node reference to add
484 *	@len: length of this physical node
485 *
486 *	Should only be used to report nodes for which space has been allocated
487 *	by jffs2_reserve_space.
488 *
489 *	Must be called with the alloc_sem held.
490 */
491
492struct jffs2_raw_node_ref *jffs2_add_physical_node_ref(struct jffs2_sb_info *c,
493						       uint32_t ofs, uint32_t len,
494						       struct jffs2_inode_cache *ic)
495{
496	struct jffs2_eraseblock *jeb;
497	struct jffs2_raw_node_ref *new;
498
499	jeb = &c->blocks[ofs / c->sector_size];
500
501	jffs2_dbg(1, "%s(): Node at 0x%x(%d), size 0x%x\n",
502		  __func__, ofs & ~3, ofs & 3, len);
503#if 1
504	/* Allow non-obsolete nodes only to be added at the end of c->nextblock, 
505	   if c->nextblock is set. Note that wbuf.c will file obsolete nodes
506	   even after refiling c->nextblock */
507	if ((c->nextblock || ((ofs & 3) != REF_OBSOLETE))
508	    && (jeb != c->nextblock || (ofs & ~3) != jeb->offset + (c->sector_size - jeb->free_size))) {
509		pr_warn("argh. node added in wrong place at 0x%08x(%d)\n",
510			ofs & ~3, ofs & 3);
511		if (c->nextblock)
512			pr_warn("nextblock 0x%08x", c->nextblock->offset);
513		else
514			pr_warn("No nextblock");
515		pr_cont(", expected at %08x\n",
516			jeb->offset + (c->sector_size - jeb->free_size));
517		return ERR_PTR(-EINVAL);
518	}
519#endif
520	spin_lock(&c->erase_completion_lock);
521
522	new = jffs2_link_node_ref(c, jeb, ofs, len, ic);
523
524	if (!jeb->free_size && !jeb->dirty_size && !ISDIRTY(jeb->wasted_size)) {
525		/* If it lives on the dirty_list, jffs2_reserve_space will put it there */
526		jffs2_dbg(1, "Adding full erase block at 0x%08x to clean_list (free 0x%08x, dirty 0x%08x, used 0x%08x\n",
527			  jeb->offset, jeb->free_size, jeb->dirty_size,
528			  jeb->used_size);
529		if (jffs2_wbuf_dirty(c)) {
530			/* Flush the last write in the block if it's outstanding */
531			spin_unlock(&c->erase_completion_lock);
532			jffs2_flush_wbuf_pad(c);
533			spin_lock(&c->erase_completion_lock);
534		}
535
536		list_add_tail(&jeb->list, &c->clean_list);
537		c->nextblock = NULL;
538	}
539	jffs2_dbg_acct_sanity_check_nolock(c,jeb);
540	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
541
542	spin_unlock(&c->erase_completion_lock);
543
544	return new;
545}
546
547
548void jffs2_complete_reservation(struct jffs2_sb_info *c)
549{
550	jffs2_dbg(1, "jffs2_complete_reservation()\n");
551	spin_lock(&c->erase_completion_lock);
552	jffs2_garbage_collect_trigger(c);
553	spin_unlock(&c->erase_completion_lock);
554	mutex_unlock(&c->alloc_sem);
555}
556
557static inline int on_list(struct list_head *obj, struct list_head *head)
558{
559	struct list_head *this;
560
561	list_for_each(this, head) {
562		if (this == obj) {
563			jffs2_dbg(1, "%p is on list at %p\n", obj, head);
564			return 1;
565
566		}
567	}
568	return 0;
569}
570
571void jffs2_mark_node_obsolete(struct jffs2_sb_info *c, struct jffs2_raw_node_ref *ref)
572{
573	struct jffs2_eraseblock *jeb;
574	int blocknr;
575	struct jffs2_unknown_node n;
576	int ret, addedsize;
577	size_t retlen;
578	uint32_t freed_len;
579
580	if(unlikely(!ref)) {
581		pr_notice("EEEEEK. jffs2_mark_node_obsolete called with NULL node\n");
582		return;
583	}
584	if (ref_obsolete(ref)) {
585		jffs2_dbg(1, "%s(): called with already obsolete node at 0x%08x\n",
586			  __func__, ref_offset(ref));
587		return;
588	}
589	blocknr = ref->flash_offset / c->sector_size;
590	if (blocknr >= c->nr_blocks) {
591		pr_notice("raw node at 0x%08x is off the end of device!\n",
592			  ref->flash_offset);
593		BUG();
594	}
595	jeb = &c->blocks[blocknr];
596
597	if (jffs2_can_mark_obsolete(c) && !jffs2_is_readonly(c) &&
598	    !(c->flags & (JFFS2_SB_FLAG_SCANNING | JFFS2_SB_FLAG_BUILDING))) {
599		/* Hm. This may confuse static lock analysis. If any of the above
600		   three conditions is false, we're going to return from this
601		   function without actually obliterating any nodes or freeing
602		   any jffs2_raw_node_refs. So we don't need to stop erases from
603		   happening, or protect against people holding an obsolete
604		   jffs2_raw_node_ref without the erase_completion_lock. */
605		mutex_lock(&c->erase_free_sem);
606	}
607
608	spin_lock(&c->erase_completion_lock);
609
610	freed_len = ref_totlen(c, jeb, ref);
611
612	if (ref_flags(ref) == REF_UNCHECKED) {
613		D1(if (unlikely(jeb->unchecked_size < freed_len)) {
614				pr_notice("raw unchecked node of size 0x%08x freed from erase block %d at 0x%08x, but unchecked_size was already 0x%08x\n",
615					  freed_len, blocknr,
616					  ref->flash_offset, jeb->used_size);
617			BUG();
618		})
619			jffs2_dbg(1, "Obsoleting previously unchecked node at 0x%08x of len %x\n",
620				  ref_offset(ref), freed_len);
621		jeb->unchecked_size -= freed_len;
622		c->unchecked_size -= freed_len;
623	} else {
624		D1(if (unlikely(jeb->used_size < freed_len)) {
625				pr_notice("raw node of size 0x%08x freed from erase block %d at 0x%08x, but used_size was already 0x%08x\n",
626					  freed_len, blocknr,
627					  ref->flash_offset, jeb->used_size);
628			BUG();
629		})
630			jffs2_dbg(1, "Obsoleting node at 0x%08x of len %#x: ",
631				  ref_offset(ref), freed_len);
632		jeb->used_size -= freed_len;
633		c->used_size -= freed_len;
634	}
635
636	// Take care, that wasted size is taken into concern
637	if ((jeb->dirty_size || ISDIRTY(jeb->wasted_size + freed_len)) && jeb != c->nextblock) {
638		jffs2_dbg(1, "Dirtying\n");
639		addedsize = freed_len;
640		jeb->dirty_size += freed_len;
641		c->dirty_size += freed_len;
642
643		/* Convert wasted space to dirty, if not a bad block */
644		if (jeb->wasted_size) {
645			if (on_list(&jeb->list, &c->bad_used_list)) {
646				jffs2_dbg(1, "Leaving block at %08x on the bad_used_list\n",
647					  jeb->offset);
648				addedsize = 0; /* To fool the refiling code later */
649			} else {
650				jffs2_dbg(1, "Converting %d bytes of wasted space to dirty in block at %08x\n",
651					  jeb->wasted_size, jeb->offset);
652				addedsize += jeb->wasted_size;
653				jeb->dirty_size += jeb->wasted_size;
654				c->dirty_size += jeb->wasted_size;
655				c->wasted_size -= jeb->wasted_size;
656				jeb->wasted_size = 0;
657			}
658		}
659	} else {
660		jffs2_dbg(1, "Wasting\n");
661		addedsize = 0;
662		jeb->wasted_size += freed_len;
663		c->wasted_size += freed_len;
664	}
665	ref->flash_offset = ref_offset(ref) | REF_OBSOLETE;
666
667	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
668	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
669
670	if (c->flags & JFFS2_SB_FLAG_SCANNING) {
671		/* Flash scanning is in progress. Don't muck about with the block
672		   lists because they're not ready yet, and don't actually
673		   obliterate nodes that look obsolete. If they weren't
674		   marked obsolete on the flash at the time they _became_
675		   obsolete, there was probably a reason for that. */
676		spin_unlock(&c->erase_completion_lock);
677		/* We didn't lock the erase_free_sem */
678		return;
679	}
680
681	if (jeb == c->nextblock) {
682		jffs2_dbg(2, "Not moving nextblock 0x%08x to dirty/erase_pending list\n",
683			  jeb->offset);
684	} else if (!jeb->used_size && !jeb->unchecked_size) {
685		if (jeb == c->gcblock) {
686			jffs2_dbg(1, "gcblock at 0x%08x completely dirtied. Clearing gcblock...\n",
687				  jeb->offset);
688			c->gcblock = NULL;
689		} else {
690			jffs2_dbg(1, "Eraseblock at 0x%08x completely dirtied. Removing from (dirty?) list...\n",
691				  jeb->offset);
692			list_del(&jeb->list);
693		}
694		if (jffs2_wbuf_dirty(c)) {
695			jffs2_dbg(1, "...and adding to erasable_pending_wbuf_list\n");
696			list_add_tail(&jeb->list, &c->erasable_pending_wbuf_list);
697		} else {
698			if (jiffies & 127) {
699				/* Most of the time, we just erase it immediately. Otherwise we
700				   spend ages scanning it on mount, etc. */
701				jffs2_dbg(1, "...and adding to erase_pending_list\n");
702				list_add_tail(&jeb->list, &c->erase_pending_list);
703				c->nr_erasing_blocks++;
704				jffs2_garbage_collect_trigger(c);
705			} else {
706				/* Sometimes, however, we leave it elsewhere so it doesn't get
707				   immediately reused, and we spread the load a bit. */
708				jffs2_dbg(1, "...and adding to erasable_list\n");
709				list_add_tail(&jeb->list, &c->erasable_list);
710			}
711		}
712		jffs2_dbg(1, "Done OK\n");
713	} else if (jeb == c->gcblock) {
714		jffs2_dbg(2, "Not moving gcblock 0x%08x to dirty_list\n",
715			  jeb->offset);
716	} else if (ISDIRTY(jeb->dirty_size) && !ISDIRTY(jeb->dirty_size - addedsize)) {
717		jffs2_dbg(1, "Eraseblock at 0x%08x is freshly dirtied. Removing from clean list...\n",
718			  jeb->offset);
719		list_del(&jeb->list);
720		jffs2_dbg(1, "...and adding to dirty_list\n");
721		list_add_tail(&jeb->list, &c->dirty_list);
722	} else if (VERYDIRTY(c, jeb->dirty_size) &&
723		   !VERYDIRTY(c, jeb->dirty_size - addedsize)) {
724		jffs2_dbg(1, "Eraseblock at 0x%08x is now very dirty. Removing from dirty list...\n",
725			  jeb->offset);
726		list_del(&jeb->list);
727		jffs2_dbg(1, "...and adding to very_dirty_list\n");
728		list_add_tail(&jeb->list, &c->very_dirty_list);
729	} else {
730		jffs2_dbg(1, "Eraseblock at 0x%08x not moved anywhere. (free 0x%08x, dirty 0x%08x, used 0x%08x)\n",
731			  jeb->offset, jeb->free_size, jeb->dirty_size,
732			  jeb->used_size);
733	}
734
735	spin_unlock(&c->erase_completion_lock);
736
737	if (!jffs2_can_mark_obsolete(c) || jffs2_is_readonly(c) ||
738		(c->flags & JFFS2_SB_FLAG_BUILDING)) {
739		/* We didn't lock the erase_free_sem */
740		return;
741	}
742
743	/* The erase_free_sem is locked, and has been since before we marked the node obsolete
744	   and potentially put its eraseblock onto the erase_pending_list. Thus, we know that
745	   the block hasn't _already_ been erased, and that 'ref' itself hasn't been freed yet
746	   by jffs2_free_jeb_node_refs() in erase.c. Which is nice. */
747
748	jffs2_dbg(1, "obliterating obsoleted node at 0x%08x\n",
749		  ref_offset(ref));
750	ret = jffs2_flash_read(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
751	if (ret) {
752		pr_warn("Read error reading from obsoleted node at 0x%08x: %d\n",
753			ref_offset(ref), ret);
754		goto out_erase_sem;
755	}
756	if (retlen != sizeof(n)) {
757		pr_warn("Short read from obsoleted node at 0x%08x: %zd\n",
758			ref_offset(ref), retlen);
759		goto out_erase_sem;
760	}
761	if (PAD(je32_to_cpu(n.totlen)) != PAD(freed_len)) {
762		pr_warn("Node totlen on flash (0x%08x) != totlen from node ref (0x%08x)\n",
763			je32_to_cpu(n.totlen), freed_len);
764		goto out_erase_sem;
765	}
766	if (!(je16_to_cpu(n.nodetype) & JFFS2_NODE_ACCURATE)) {
767		jffs2_dbg(1, "Node at 0x%08x was already marked obsolete (nodetype 0x%04x)\n",
768			  ref_offset(ref), je16_to_cpu(n.nodetype));
769		goto out_erase_sem;
770	}
771	/* XXX FIXME: This is ugly now */
772	n.nodetype = cpu_to_je16(je16_to_cpu(n.nodetype) & ~JFFS2_NODE_ACCURATE);
773	ret = jffs2_flash_write(c, ref_offset(ref), sizeof(n), &retlen, (char *)&n);
774	if (ret) {
775		pr_warn("Write error in obliterating obsoleted node at 0x%08x: %d\n",
776			ref_offset(ref), ret);
777		goto out_erase_sem;
778	}
779	if (retlen != sizeof(n)) {
780		pr_warn("Short write in obliterating obsoleted node at 0x%08x: %zd\n",
781			ref_offset(ref), retlen);
782		goto out_erase_sem;
783	}
784
785	/* Nodes which have been marked obsolete no longer need to be
786	   associated with any inode. Remove them from the per-inode list.
787
788	   Note we can't do this for NAND at the moment because we need
789	   obsolete dirent nodes to stay on the lists, because of the
790	   horridness in jffs2_garbage_collect_deletion_dirent(). Also
791	   because we delete the inocache, and on NAND we need that to
792	   stay around until all the nodes are actually erased, in order
793	   to stop us from giving the same inode number to another newly
794	   created inode. */
795	if (ref->next_in_ino) {
796		struct jffs2_inode_cache *ic;
797		struct jffs2_raw_node_ref **p;
798
799		spin_lock(&c->erase_completion_lock);
800
801		ic = jffs2_raw_ref_to_ic(ref);
802		for (p = &ic->nodes; (*p) != ref; p = &((*p)->next_in_ino))
803			;
804
805		*p = ref->next_in_ino;
806		ref->next_in_ino = NULL;
807
808		switch (ic->class) {
809#ifdef CONFIG_JFFS2_FS_XATTR
810			case RAWNODE_CLASS_XATTR_DATUM:
811				jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
812				break;
813			case RAWNODE_CLASS_XATTR_REF:
814				jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
815				break;
816#endif
817			default:
818				if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
819					jffs2_del_ino_cache(c, ic);
820				break;
821		}
822		spin_unlock(&c->erase_completion_lock);
823	}
824
825 out_erase_sem:
826	mutex_unlock(&c->erase_free_sem);
827}
828
829int jffs2_thread_should_wake(struct jffs2_sb_info *c)
830{
831	int ret = 0;
832	uint32_t dirty;
833	int nr_very_dirty = 0;
834	struct jffs2_eraseblock *jeb;
835
836	if (!list_empty(&c->erase_complete_list) ||
837	    !list_empty(&c->erase_pending_list))
838		return 1;
839
840	if (c->unchecked_size) {
841		jffs2_dbg(1, "jffs2_thread_should_wake(): unchecked_size %d, checked_ino #%d\n",
842			  c->unchecked_size, c->checked_ino);
843		return 1;
844	}
845
846	/* dirty_size contains blocks on erase_pending_list
847	 * those blocks are counted in c->nr_erasing_blocks.
848	 * If one block is actually erased, it is not longer counted as dirty_space
849	 * but it is counted in c->nr_erasing_blocks, so we add it and subtract it
850	 * with c->nr_erasing_blocks * c->sector_size again.
851	 * Blocks on erasable_list are counted as dirty_size, but not in c->nr_erasing_blocks
852	 * This helps us to force gc and pick eventually a clean block to spread the load.
853	 */
854	dirty = c->dirty_size + c->erasing_size - c->nr_erasing_blocks * c->sector_size;
855
856	if (c->nr_free_blocks + c->nr_erasing_blocks < c->resv_blocks_gctrigger &&
857			(dirty > c->nospc_dirty_size))
858		ret = 1;
859
860	list_for_each_entry(jeb, &c->very_dirty_list, list) {
861		nr_very_dirty++;
862		if (nr_very_dirty == c->vdirty_blocks_gctrigger) {
863			ret = 1;
864			/* In debug mode, actually go through and count them all */
865			D1(continue);
866			break;
867		}
868	}
869
870	jffs2_dbg(1, "%s(): nr_free_blocks %d, nr_erasing_blocks %d, dirty_size 0x%x, vdirty_blocks %d: %s\n",
871		  __func__, c->nr_free_blocks, c->nr_erasing_blocks,
872		  c->dirty_size, nr_very_dirty, ret ? "yes" : "no");
873
874	return ret;
875}