[JFFS2] Add paranoia debugging for superblock counts

The problem fixed in commit 014b164e1392a166fe96e003d2f0e7ad2e2a0bb7
(space leak with in-band cleanmarkers) would have been caught a lot
quicker if our paranoid debugging mode had included adding up the size
counts from all the eraseblocks and comparing the totals with the counts
in the superblock. Add that.

Make jffs2_mark_erased_block() file the newly-erased block on the
free_list before calling the debug function, to make it happy.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

2 files changed, 136 insertions, 3 deletions

diff --git a/fs/jffs2/debug.c b/fs/jffs2/debug.c
index 6607931..590bdd6 100644
--- a/fs/jffs2/debug.c
+++ b/fs/jffs2/debug.c
@@ -153,6 +153,135 @@ __jffs2_dbg_prewrite_paranoia_check(struct jffs2_sb_info *c,
 	kfree(buf);
 }
 
+void __jffs2_dbg_superblock_counts(struct jffs2_sb_info *c)
+{
+	struct jffs2_eraseblock *jeb;
+	uint32_t free = 0, dirty = 0, used = 0, wasted = 0,
+		erasing = 0, bad = 0, unchecked = 0;
+	int nr_counted = 0;
+	int dump = 0;
+
+	if (c->gcblock) {
+		nr_counted++;
+		free += c->gcblock->free_size;
+		dirty += c->gcblock->dirty_size;
+		used += c->gcblock->used_size;
+		wasted += c->gcblock->wasted_size;
+		unchecked += c->gcblock->unchecked_size;
+	}
+	if (c->nextblock) {
+		nr_counted++;
+		free += c->nextblock->free_size;
+		dirty += c->nextblock->dirty_size;
+		used += c->nextblock->used_size;
+		wasted += c->nextblock->wasted_size;
+		unchecked += c->nextblock->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->clean_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->very_dirty_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->dirty_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->erasable_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->erasable_pending_wbuf_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->erase_pending_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->free_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+	list_for_each_entry(jeb, &c->bad_used_list, list) {
+		nr_counted++;
+		free += jeb->free_size;
+		dirty += jeb->dirty_size;
+		used += jeb->used_size;
+		wasted += jeb->wasted_size;
+		unchecked += jeb->unchecked_size;
+	}
+
+	list_for_each_entry(jeb, &c->erasing_list, list) {
+		nr_counted++;
+		erasing += c->sector_size;
+	}
+	list_for_each_entry(jeb, &c->erase_complete_list, list) {
+		nr_counted++;
+		erasing += c->sector_size;
+	}
+	list_for_each_entry(jeb, &c->bad_list, list) {
+		nr_counted++;
+		bad += c->sector_size;
+	}
+
+#define check(sz) \
+	if (sz != c->sz##_size) {			\
+		printk(KERN_WARNING #sz "_size mismatch counted 0x%x, c->" #sz "_size 0x%x\n", \
+		       sz, c->sz##_size);		\
+		dump = 1;				\
+	}
+	check(free);
+	check(dirty);
+	check(used);
+	check(wasted);
+	check(unchecked);
+	check(bad);
+	check(erasing);
+#undef check
+
+	if (nr_counted != c->nr_blocks) {
+		printk(KERN_WARNING "%s counted only 0x%x blocks of 0x%x. Where are the others?\n",
+		       __func__, nr_counted, c->nr_blocks);
+		dump = 1;
+	}
+
+	if (dump) {
+		__jffs2_dbg_dump_block_lists_nolock(c);
+		BUG();
+	}
+}
+
 /*
  * Check the space accounting and node_ref list correctness for the JFFS2 erasable block 'jeb'.
  */
@@ -229,6 +358,9 @@ __jffs2_dbg_acct_paranoia_check_nolock(struct jffs2_sb_info *c,
 	}
 #endif
 
+	if (!(c->flags & (JFFS2_SB_FLAG_BUILDING|JFFS2_SB_FLAG_SCANNING)))
+		__jffs2_dbg_superblock_counts(c);
+
 	return;
 
 error:
diff --git a/fs/jffs2/erase.c b/fs/jffs2/erase.c
index bdc6a7b..65d9194 100644
--- a/fs/jffs2/erase.c
+++ b/fs/jffs2/erase.c
@@ -460,12 +460,13 @@ static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseb
 	if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
 		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
 
-	jffs2_dbg_acct_sanity_check_nolock(c,jeb);
-	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
-
 	list_add_tail(&jeb->list, &c->free_list);
 	c->nr_erasing_blocks--;
 	c->nr_free_blocks++;
+
+	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
+	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
+
 	spin_unlock(&c->erase_completion_lock);
 	mutex_unlock(&c->erase_free_sem);
 	wake_up(&c->erase_wait);