# HG changeset patch
# User Daniel Stodden <daniel.stodden@xxxxxxxxxx>
# Date 1267200019 28800
# Node ID 183cbdaef8d14d863465c18bc06cbc7849c30bbc
# Parent  96525ab0393ab7cab181de757a495f57284ccd01
blkfront: Move xenstore accesses off the device release path.

Not holding the bdev mutex should be slightly more robust. Also helps
getting blkfront_closing to complement xlvbd_alloc_gendisk.

Signed-off-by: Daniel Stodden <daniel.stodden@xxxxxxxxxx>

diff -r 96525ab0393a -r 183cbdaef8d1 drivers/block/xen-blkfront.c
--- a/drivers/block/xen-blkfront.c	Fri Feb 26 07:27:44 2010 -0800
+++ b/drivers/block/xen-blkfront.c	Fri Feb 26 08:00:19 2010 -0800
@@ -927,8 +927,8 @@
 
 	dev_dbg(&dev->dev, "blkfront_closing: %s removed\n", dev->nodename);
 
-	if (info->rq == NULL)
-		goto out;
+	if (!info->gd)
+		return;
 
 	spin_lock_irqsave(&blkif_io_lock, flags);
 
@@ -949,9 +949,6 @@
 
 	put_disk(info->gd);
 	info->gd = NULL;
-
- out:
-	xenbus_frontend_closed(dev);
 }
 
 static void blkfront_close(struct blkfront_info *info)
@@ -959,6 +956,7 @@
 	struct xenbus_device *dev = info->xbdev;
 	struct gendisk *gd = info->gd;
 	struct block_device *bd;
+	int inuse;
 
 	if (!gd) {
 		xenbus_frontend_closed(dev);
@@ -973,14 +971,18 @@
 
 	mutex_lock(&bd->bd_mutex);
 
-	if (info->users > 0)
-		xenbus_dev_error(dev, -EBUSY,
-				 "Device in use; refusing to close");
-	else
+	inuse = !!info->users;
+	if (!inuse)
 		blkfront_closing(dev);
 
 	mutex_unlock(&bd->bd_mutex);
 	bdput(bd);
+
+	if (inuse)
+		xenbus_dev_error(dev, -EBUSY,
+				 "Device in use; refusing to close");
+	else
+		xenbus_frontend_closed(dev);
 }
 
 /**
@@ -1051,8 +1053,10 @@
 		struct xenbus_device *dev = info->xbdev;
 		enum xenbus_state state = xenbus_read_driver_state(dev->otherend);
 
-		if (state == XenbusStateClosing && info->is_ready)
+		if (state == XenbusStateClosing && info->is_ready) {
 			blkfront_closing(dev);
+			xenbus_frontend_closed(dev);
+		}
 	}
 	return 0;
 }