[sheepdog] [PATCH] collie/farm: save vmstate objects during cluster-wide snapshot

[Kai Zhang]

Without this patch, qemu's 'loadvm' command will fail after
loading cluster-wide snapshot to a new cluster.

Signed-off-by: Kai Zhang <kyle at zelin.io>
---
 collie/cluster.c         |   12 +++++++++++-
 include/sheepdog_proto.h |    5 +++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/collie/cluster.c b/collie/cluster.c
index c0c4ab2..4e94ad2 100644
--- a/collie/cluster.c
+++ b/collie/cluster.c
@@ -253,14 +253,17 @@ static void fill_object_tree(uint32_t vid, const char *name, const char *tag,
 			  uint32_t snapid, uint32_t flags,
 			  const struct sd_inode *i, void *data)
 {
-	uint64_t vdi_oid = vid_to_vdi_oid(vid);
+	uint64_t vdi_oid = vid_to_vdi_oid(vid), vmstate_oid;
+	int nr_vmstate_object;
 
 	/* ignore active vdi */
 	if (!vdi_is_snapshot(i))
 		return;
 
+	/* fill vdi object id */
 	object_tree_insert(vdi_oid, i->nr_copies);
 
+	/* fill data object id */
 	for (uint64_t idx = 0; idx < MAX_DATA_OBJS; idx++) {
 		if (i->data_vdi_id[idx]) {
 			uint64_t oid = vid_to_data_oid(i->data_vdi_id[idx],
@@ -268,6 +271,13 @@ static void fill_object_tree(uint32_t vid, const char *name, const char *tag,
 			object_tree_insert(oid, i->nr_copies);
 		}
 	}
+
+	/* fill vmstate object id */
+	nr_vmstate_object = (i->vm_state_size / SD_DATA_OBJ_SIZE) + 1;
+	for (int idx = 0; idx < nr_vmstate_object; idx++) {
+		vmstate_oid = vid_to_vmstate_oid(vid, idx);
+		object_tree_insert(vmstate_oid, i->nr_copies);
+	}
 }
 
 static int save_snapshot(int argc, char **argv)
diff --git a/include/sheepdog_proto.h b/include/sheepdog_proto.h
index beef0a6..156457a 100644
--- a/include/sheepdog_proto.h
+++ b/include/sheepdog_proto.h
@@ -307,6 +307,11 @@ static inline uint64_t vid_to_attr_oid(uint32_t vid, uint32_t attrid)
 	return ((uint64_t)vid << VDI_SPACE_SHIFT) | VDI_ATTR_BIT | attrid;
 }
 
+static inline uint64_t vid_to_vmstate_oid(uint32_t vid, uint32_t idx)
+{
+	return VMSTATE_BIT | ((uint64_t)vid << VDI_SPACE_SHIFT) | idx;
+}
+
 static inline bool vdi_is_snapshot(const struct sd_inode *inode)
 {
 	return !!inode->snap_ctime;
-- 
1.7.9.5