[sheepdog] [PATCH RFT 1/4] sheep: let vdi state have parent VID

[Hitoshi Mitake]

This is a preparation patch.

Cc: Saeki Masaki <saeki.masaki at po.ntts.co.jp>
Cc: Yuka Kawasaki <kawasaki.yuka at po.ntts.co.jp>
Signed-off-by: Hitoshi Mitake <mitake.hitoshi at lab.ntt.co.jp>
---
 include/internal_proto.h |  1 +
 sheep/group.c            |  3 ++-
 sheep/ops.c              |  7 ++++---
 sheep/plain_store.c      |  2 +-
 sheep/sheep_priv.h       |  2 +-
 sheep/vdi.c              | 15 ++++++++++++++-
 6 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/include/internal_proto.h b/include/internal_proto.h
index 3f5d77f..65087cf 100644
--- a/include/internal_proto.h
+++ b/include/internal_proto.h
@@ -359,6 +359,7 @@ struct vdi_state {
 	uint8_t copy_policy;
 	uint8_t block_size_shift;
 	uint8_t __pad[3];
+	uint32_t parent_vid;
 
 	uint32_t lock_state;
 
diff --git a/sheep/group.c b/sheep/group.c
index 095b7c5..f07ffb8 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -510,7 +510,8 @@ retry:
 		if (vs[i].deleted)
 			atomic_set_bit(vs[i].vid, sys->vdi_deleted);
 		add_vdi_state(vs[i].vid, vs[i].nr_copies, vs[i].snapshot,
-			      vs[i].copy_policy, vs[i].block_size_shift);
+			      vs[i].copy_policy, vs[i].block_size_shift,
+			      vs[i].parent_vid);
 	}
 out:
 	free(vs);
diff --git a/sheep/ops.c b/sheep/ops.c
index 448fd8e..f87372d 100644
--- a/sheep/ops.c
+++ b/sheep/ops.c
@@ -664,14 +664,15 @@ static int cluster_notify_vdi_add(const struct sd_req *req, struct sd_rsp *rsp,
 		add_vdi_state(req->vdi_state.old_vid,
 			      get_vdi_copy_number(req->vdi_state.old_vid),
 			      true, req->vdi_state.copy_policy,
-			      get_vdi_block_size_shift(req->vdi_state.old_vid));
+			      get_vdi_block_size_shift(req->vdi_state.old_vid),
+			      0);
 
 	if (req->vdi_state.set_bitmap)
 		atomic_set_bit(req->vdi_state.new_vid, sys->vdi_inuse);
 
 	add_vdi_state(req->vdi_state.new_vid, req->vdi_state.copies, false,
 		      req->vdi_state.copy_policy,
-		      req->vdi_state.block_size_shift);
+		      req->vdi_state.block_size_shift, req->vdi_state.old_vid);
 
 	return SD_RES_SUCCESS;
 }
@@ -772,7 +773,7 @@ static int cluster_alter_vdi_copy(const struct sd_req *req, struct sd_rsp *rsp,
 	uint32_t block_size_shift = req->vdi_state.block_size_shift;
 	struct vnode_info *vinfo;
 
-	add_vdi_state(vid, nr_copies, false, 0, block_size_shift);
+	add_vdi_state(vid, nr_copies, false, 0, block_size_shift, 0);
 
 	vinfo = get_vnode_info();
 	start_recovery(vinfo, vinfo, false);
diff --git a/sheep/plain_store.c b/sheep/plain_store.c
index cb90e31..a7b0864 100644
--- a/sheep/plain_store.c
+++ b/sheep/plain_store.c
@@ -283,7 +283,7 @@ static int init_vdi_state(uint64_t oid, const char *wd, uint32_t epoch)
 	}
 	add_vdi_state(oid_to_vid(oid), inode->nr_copies,
 		      vdi_is_snapshot(inode), inode->copy_policy,
-		      inode->block_size_shift);
+		      inode->block_size_shift, inode->parent_vdi_id);
 
 	if (inode->name[0] == '\0')
 		atomic_set_bit(oid_to_vid(oid), sys->vdi_deleted);
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index a724754..5f9c534 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -332,7 +332,7 @@ uint8_t get_vdi_block_size_shift(uint32_t vid);
 int get_obj_copy_number(uint64_t oid, int nr_zones);
 int get_req_copy_number(struct request *req);
 int add_vdi_state(uint32_t vid, int nr_copies, bool snapshot,
-		  uint8_t, uint8_t block_size_shift);
+		  uint8_t, uint8_t block_size_shift, uint32_t parent_vid);
 int vdi_exist(uint32_t vid);
 int vdi_create(const struct vdi_iocb *iocb, uint32_t *new_vid);
 int vdi_snapshot(const struct vdi_iocb *iocb, uint32_t *new_vid);
diff --git a/sheep/vdi.c b/sheep/vdi.c
index 392b860..fea7a32 100644
--- a/sheep/vdi.c
+++ b/sheep/vdi.c
@@ -18,6 +18,7 @@ struct vdi_state_entry {
 	bool snapshot;
 	bool deleted;
 	uint8_t copy_policy;
+	uint32_t parent_vid;
 	struct rb_node node;
 
 	enum lock_state lock_state;
@@ -189,7 +190,7 @@ int get_req_copy_number(struct request *req)
 }
 
 int add_vdi_state(uint32_t vid, int nr_copies, bool snapshot,
-		  uint8_t cp, uint8_t block_size_shift)
+		  uint8_t cp, uint8_t block_size_shift, uint32_t parent_vid)
 {
 	struct vdi_state_entry *entry, *old;
 
@@ -199,6 +200,7 @@ int add_vdi_state(uint32_t vid, int nr_copies, bool snapshot,
 	entry->snapshot = snapshot;
 	entry->copy_policy = cp;
 	entry->block_size_shift = block_size_shift;
+	entry->parent_vid = parent_vid;
 
 	entry->lock_state = LOCK_STATE_UNLOCKED;
 	memset(&entry->owner, 0, sizeof(struct node_id));
@@ -226,6 +228,16 @@ int add_vdi_state(uint32_t vid, int nr_copies, bool snapshot,
 		entry->snapshot = snapshot;
 		entry->copy_policy = cp;
 		entry->block_size_shift = block_size_shift;
+
+		if (parent_vid) {
+			if (!snapshot)
+				sd_warn("caution, updating parent VID of VID: %"
+					PRIx32 " (old parent VID: %" PRIx32
+					", new parent VID: %"PRIx32 ")", vid,
+					entry->parent_vid, parent_vid);
+
+			entry->parent_vid = parent_vid;
+		}
 	}
 
 	sd_rw_unlock(&vdi_state_lock);
@@ -256,6 +268,7 @@ int fill_vdi_state_list(const struct sd_req *hdr,
 		vs[last].lock_state = entry->lock_state;
 		vs[last].lock_owner = entry->owner;
 		vs[last].nr_participants = entry->nr_participants;
+		vs[last].parent_vid = entry->parent_vid;
 		for (int i = 0; i < vs[last].nr_participants; i++) {
 			vs[last].participants_state[i] =
 				entry->participants_state[i];
-- 
1.8.3.2