Merge branch 'stable/for-jens-3.18' of...

Merge branch 'stable/for-jens-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-3.18/drivers

Konrad writes:

This pull has two fixes and one cleanup. Nothing earthshattering.

drivers/block/xen-blkback/blkback.c

@@ -763,6 +763,7 @@ static int xen_blkbk_map(struct xen_blkif *blkif,
 			BUG_ON(new_map_idx >= segs_to_map);
 			if (unlikely(map[new_map_idx].status != 0)) {
 				pr_debug(DRV_PFX "invalid buffer -- could not remap it\n");
+				put_free_pages(blkif, &pages[seg_idx]->page, 1);
 				pages[seg_idx]->handle = BLKBACK_INVALID_HANDLE;
 				ret |= 1;
 				goto next;

drivers/block/xen-blkback/xenbus.c

@@ -270,6 +270,9 @@ static int xen_blkif_disconnect(struct xen_blkif *blkif)
 		blkif->blk_rings.common.sring = NULL;
 	}
 
+	/* Remove all persistent grants and the cache of ballooned pages. */
+	xen_blkbk_free_caches(blkif);
+
 	return 0;
 }
 
@@ -281,9 +284,6 @@ static void xen_blkif_free(struct xen_blkif *blkif)
 	xen_blkif_disconnect(blkif);
 	xen_vbd_free(&blkif->vbd);
 
-	/* Remove all persistent grants and the cache of ballooned pages. */
-	xen_blkbk_free_caches(blkif);
-
 	/* Make sure everything is drained before shutting down */
 	BUG_ON(blkif->persistent_gnt_c != 0);
 	BUG_ON(atomic_read(&blkif->persistent_gnt_in_use) != 0);

drivers/block/xen-blkfront.c

@@ -582,6 +582,14 @@ static inline void flush_requests(struct blkfront_info *info)
 		notify_remote_via_irq(info->irq);
 }
 
+static inline bool blkif_request_flush_valid(struct request *req,
+					     struct blkfront_info *info)
+{
+	return ((req->cmd_type != REQ_TYPE_FS) ||
+		((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) &&
+		!info->flush_op));
+}
+
 /*
  * do_blkif_request
  *  read a block; request is in a request queue
@@ -604,9 +612,7 @@ static void do_blkif_request(struct request_queue *rq)
 
 		blk_start_request(req);
 
-		if ((req->cmd_type != REQ_TYPE_FS) ||
-		    ((req->cmd_flags & (REQ_FLUSH | REQ_FUA)) &&
-		    !info->flush_op)) {
+		if (blkif_request_flush_valid(req, info)) {
 			__blk_end_request_all(req, -EIO);
 			continue;
 		}