From c1549fea6b99ff4cf838a890d007ca3445be2e35 Mon Sep 17 00:00:00 2001
From: Alex Elder <elder@inktank.com>
Date: Wed, 1 May 2013 12:43:03 -0500
Subject: [PATCH] --- yaml --- r: 373541 b: refs/heads/master c:
 15228ede7d9437b0dcfe9331c9830b3646fdadf7 h: refs/heads/master i:   373539:
 2afd4aac3dc11ad549d0310799b5c7df737f4437 v: v3

---
 [refs]                    |  2 +-
 trunk/drivers/block/rbd.c | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 86096900612a..a5af47e19ec4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 33dca39f5c0c750d37d3d89ce8ae66be08280a45
+refs/heads/master: 15228ede7d9437b0dcfe9331c9830b3646fdadf7
diff --git a/trunk/drivers/block/rbd.c b/trunk/drivers/block/rbd.c
index 0ca959f5c934..3f58aba6461f 100644
--- a/trunk/drivers/block/rbd.c
+++ b/trunk/drivers/block/rbd.c
@@ -3114,6 +3114,25 @@ static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev)
 	return ret;
 }
 
+/*
+ * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
+ * has disappeared from the (just updated) snapshot context.
+ */
+static void rbd_exists_validate(struct rbd_device *rbd_dev)
+{
+	u64 snap_id;
+
+	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
+		return;
+
+	snap_id = rbd_dev->spec->snap_id;
+	if (snap_id == CEPH_NOSNAP)
+		return;
+
+	if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
+		clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
+}
+
 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
 {
 	u64 image_size;
@@ -3126,6 +3145,10 @@ static int rbd_dev_refresh(struct rbd_device *rbd_dev)
 		ret = rbd_dev_v1_refresh(rbd_dev);
 	else
 		ret = rbd_dev_v2_refresh(rbd_dev);
+
+	/* If it's a mapped snapshot, validate its EXISTS flag */
+
+	rbd_exists_validate(rbd_dev);
 	mutex_unlock(&ctl_mutex);
 	if (ret)
 		rbd_warn(rbd_dev, "got notification but failed to "