From: Filippos Giannakos <philipgian@grnet.gr>
Date: Tue, 10 Sep 2013 13:19:12 +0000 (+0300)
Subject: vlmc: Honor flush req by stall until all reqs done
X-Git-Url: https://code.grnet.gr/git/archipelago/commitdiff_plain/ae8c75f437ee2ee1764d66422d2406fd5ec0a77d?hp=addcb81e90629e4ad9cfcfe2d5a87fbcd6631c55

vlmc: Honor flush req by stall until all reqs done
---

diff --git a/xseg/peers/user/mt-vlmcd.c b/xseg/peers/user/mt-vlmcd.c
index 03ed5db..7e99eb6 100644
--- a/xseg/peers/user/mt-vlmcd.c
+++ b/xseg/peers/user/mt-vlmcd.c
@@ -255,6 +255,14 @@ static int conclude_pr(struct peerd *peer, struct peer_req *pr)
 	return 0;
 }
 
+static int should_freeze_volume(struct xseg_request *req)
+{
+	if (req->op == X_CLOSE || req->op == X_SNAPSHOT ||
+		(req->op == X_WRITE && !req->size && (req->flags & XF_FLUSH)))
+		return 1;
+	return 0;
+}
+
 static int do_accepted_pr(struct peerd *peer, struct peer_req *pr)
 {
 	struct vlmcd *vlmc = __get_vlmcd(peer);
@@ -283,7 +291,7 @@ static int do_accepted_pr(struct peerd *peer, struct peer_req *pr)
 		return -1;
 	}
 
-	if (pr->req->op == X_CLOSE || pr->req->op == X_SNAPSHOT){
+	if (should_freeze_volume(pr->req)){
 		XSEGLOG2(&lc, I, "Freezing volume %s", vi->name);
 		vi->flags |= VF_VOLUME_FREEZED;
 		if (vi->active_reqs){
@@ -299,6 +307,7 @@ static int do_accepted_pr(struct peerd *peer, struct peer_req *pr)
 			//assert vi->pending_pr == pr
 			vi->pending_pr = NULL;
 		}
+
 	}
 
 	vi->active_reqs++;
@@ -309,6 +318,7 @@ static int do_accepted_pr(struct peerd *peer, struct peer_req *pr)
 			(pr->req->flags & (XF_FLUSH|XF_FUA))){
 		//hanlde flush requests here, so we don't mess with mapper
 		//because of the -1 offset
+		vi->flags &= ~VF_VOLUME_FREEZED;
 		XSEGLOG2(&lc, I, "Completing flush request");
 		pr->req->serviced = pr->req->size;
 		conclude_pr(peer, pr);