[Sheepdog] [PATCH 09/14] check epoch when the request causes local access

[MORITA Kazutaka]

Even though SD_FLAG_CMD_DIRECT is not set, local accesses could happen
if the target object is in the local node.

Signed-off-by: MORITA Kazutaka <morita.kazutaka at lab.ntt.co.jp>
---
 sheep/group.c      |   10 ++++++++--
 sheep/sdnet.c      |    7 +++++--
 sheep/sheep_priv.h |    2 ++
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/sheep/group.c b/sheep/group.c
index 2826db3..28d211f 100644
--- a/sheep/group.c
+++ b/sheep/group.c
@@ -1342,7 +1342,10 @@ do_retry:
 
 			sys->nr_outstanding_io++;
 
-			if (req->rq.flags & SD_FLAG_CMD_DIRECT) {
+			if (is_access_local(req->entry, req->nr_vnodes,
+					    ((struct sd_obj_req *)&req->rq)->oid, sys->nr_sobjs) ||
+			    is_access_local(req->entry, req->nr_vnodes,
+					    ((struct sd_obj_req *)&req->rq)->cow_oid, sys->nr_sobjs)) {
 				int ret = check_epoch(req);
 				if (ret != SD_RES_SUCCESS) {
 					req->rp.result = ret;
@@ -1350,7 +1353,10 @@ do_retry:
 					list_add_tail(&req->r_wlist, &failed_req_list);
 					continue;
 				}
-			} else if (req->rq.opcode == SD_OP_READ_OBJ) {
+			}
+
+			if (!(req->rq.flags & SD_FLAG_CMD_DIRECT) &&
+			    req->rq.opcode == SD_OP_READ_OBJ) {
 				struct sd_obj_req *hdr = (struct sd_obj_req *)&req->rq;
 				uint32_t vdi_id = oid_to_vid(hdr->oid);
 				struct data_object_bmap *bmap;
diff --git a/sheep/sdnet.c b/sheep/sdnet.c
index d37e75f..1b1b7cc 100644
--- a/sheep/sdnet.c
+++ b/sheep/sdnet.c
@@ -51,11 +51,14 @@ void resume_pending_requests(void)
 		start_cpg_event_work();
 }
 
-static int is_access_local(struct sheepdog_vnode_list_entry *e, int nr_nodes,
-			   uint64_t oid, int copies)
+int is_access_local(struct sheepdog_vnode_list_entry *e, int nr_nodes,
+		    uint64_t oid, int copies)
 {
 	int i, n;
 
+	if (oid == 0)
+		return 0;
+
 	for (i = 0; i < copies; i++) {
 		n = obj_to_sheep(e, nr_nodes, oid, i);
 
diff --git a/sheep/sheep_priv.h b/sheep/sheep_priv.h
index 13a5ce2..82840de 100644
--- a/sheep/sheep_priv.h
+++ b/sheep/sheep_priv.h
@@ -166,6 +166,8 @@ void setup_ordered_sd_vnode_list(struct request *req);
 void get_ordered_sd_vnode_list(struct sheepdog_vnode_list_entry *entries,
 			       int *nr_vnodes, int *nr_nodes);
 int is_access_to_busy_objects(uint64_t oid);
+int is_access_local(struct sheepdog_vnode_list_entry *e, int nr_nodes,
+		    uint64_t oid, int copies);
 
 void resume_pending_requests(void);
 
-- 
1.5.6.5