[JFFS2] Fix writebuffer recovery in the first page of a block

For the case when nand_write_page fail with -EIO for the first page in an
eraseblock, jffs2_wbuf_recover ends up producing a BUG in jffs2_block_refile
as jeb->first_node is not yet set up (it's set up later in jffs2_wbuf_recover).
This BUG is not really a bug; it's just jffs2_wbuf_recover calling
jffs2_block_refile with the wrong second parameter.
This patch takes care of this situation.
Signed-off-by: NVitaly Wool <vwool@ru.mvista.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

fs/jffs2/wbuf.c

@@ -238,7 +238,10 @@ static void jffs2_wbuf_recover(struct jffs2_sb_info *c)
 	jeb = &c->blocks[c->wbuf_ofs / c->sector_size];
 
 	spin_lock(&c->erase_completion_lock);
+	if (c->wbuf_ofs % c->mtd->erasesize)
 		jffs2_block_refile(c, jeb, REFILE_NOTEMPTY);
+	else
+		jffs2_block_refile(c, jeb, REFILE_ANYWAY);
 	spin_unlock(&c->erase_completion_lock);
 
 	BUG_ON(!ref_obsolete(jeb->last_node));