mtd/fs/jffs2 wbuf.c,1.12,1.13

[David Woodhouse]

Update of /home/cvs/mtd/fs/jffs2
In directory phoenix.infradead.org:/tmp/cvs-serv4018

Modified Files:
	wbuf.c 
Log Message:
Comment BUG() logic in jffs2_flush_wbuf() when the accounting is screwed.
Fix jffs2_wbuf_process() logic.


Index: wbuf.c
===================================================================
RCS file: /home/cvs/mtd/fs/jffs2/wbuf.c,v
retrieving revision 1.12
retrieving revision 1.13
diff -u -r1.12 -r1.13
--- wbuf.c	20 May 2002 14:56:39 -0000	1.12
+++ wbuf.c	8 Aug 2002 11:04:40 -0000	1.13
@@ -80,17 +80,33 @@
 	
 	D1(printk(KERN_DEBUG "jffs2_wbuf_process() entered\n"));
 
-	if (!down_trylock(&c->alloc_sem)) {
-		D1(printk (KERN_DEBUG "jffs2_wbuf_process() alloc_sem got\n"));
-	
-		if(!c->nextblock || (c->nextblock->free_size < (c->wbuf_pagesize - c->wbuf_len)))
-			jffs2_flush_wbuf(c, 1); /* pad only */
-		else			
-			jffs2_flush_wbuf(c, 2); /* pad and adjust nextblock */
-		up(&c->alloc_sem);
-	} else {
+	if (down_trylock(&c->alloc_sem)) {
+		/* If someone else has the alloc_sem, they're about to
+		   write anyway. So no need to waste space by
+		   padding */
 		D1(printk (KERN_DEBUG "jffs2_wbuf_process() alloc_sem already occupied\n"));
+		return;
 	}	
+
+	D1(printk (KERN_DEBUG "jffs2_wbuf_process() alloc_sem got\n"));
+
+	if (!c->nextblock) {
+		D1(printk(KERN_DEBUG "jffs2_wbuf_process(): nextblock NULL, nothing to do\n"));
+		if (c->wbuf_len) {
+			printk(KERN_WARNING "jffs2_wbuf_process(): c->wbuf_len is 0x%03x but nextblock is NULL!\n", c->wbuf_len);
+			up(&c->alloc_sem);
+			BUG();
+		}
+		return;
+	}
+	
+	
+	/* if !c->nextblock then the tail will have got flushed from
+	   jffs2_do_reserve_space() anyway. */
+	if(c->nextblock)
+		jffs2_flush_wbuf(c, 2); /* pad and adjust nextblock */
+
+	up(&c->alloc_sem);
 }
 
 
@@ -166,8 +182,16 @@
 		spin_lock_bh(&c->erase_completion_lock);
 		if (!c->nextblock)
 			BUG();
-		if (c->nextblock->free_size < (c->wbuf_pagesize - c->wbuf_len))
+		/* wbuf_pagesize - wbuf_len is the amount of space that's to be 
+		   padded. If there is less free space in the block than that,
+		   something screwed up */
+		if (c->nextblock->free_size < (c->wbuf_pagesize - c->wbuf_len)) {
+			printk(KERN_CRIT "jffs2_flush_wbuf(): Accounting error. wbuf at 0x%08x has 0x%03x bytes, 0x%03x left.\n",
+			       c->wbuf_ofs, c->wbuf_len, c->wbuf_pagesize-c->wbuf_len);
+			printk(KERN_CRIT "jffs2_flush_wbuf(): But free_size for block at 0x%08x is only 0x%08x\n",
+			       c->nextblock->offset, c->nextblock->free_size);
 			BUG();
+		}
 		c->nextblock->free_size -= (c->wbuf_pagesize - c->wbuf_len);
 		c->nextblock->dirty_size += (c->wbuf_pagesize - c->wbuf_len);
 		spin_unlock_bh(&c->erase_completion_lock);