From d11f5f1c59cf30d3a05724c2cfdea1826305c0a5 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@newdream.net>
Date: Mon, 22 Dec 2008 13:48:40 -0800
Subject: [PATCH] mds: early_reply infrastructure

---
 src/mds/CInode.cc           |  8 ++++++--
 src/mds/CInode.h            |  2 +-
 src/mds/Server.cc           | 37 +++++++++++++++++++++++++++++++++----
 src/mds/Server.h            |  4 +++-
 src/messages/MClientReply.h |  2 ++
 5 files changed, 45 insertions(+), 8 deletions(-)

diff --git a/src/mds/CInode.cc b/src/mds/CInode.cc
index ac9903156251f..78f549de373fb 100644
--- a/src/mds/CInode.cc
+++ b/src/mds/CInode.cc
@@ -1275,12 +1275,16 @@ void CInode::decode_snap_blob(bufferlist& snapbl)
 }
 
 
-bool CInode::encode_inodestat(bufferlist& bl, snapid_t snapid)
+bool CInode::encode_inodestat(bufferlist& bl, snapid_t snapid, bool projected)
 {
   bool valid = true;
 
   // pick a version!
-  inode_t *i = &inode;
+  inode_t *i;
+  if (projected)
+    i = get_projected_inode();
+  else 
+    i = &inode;
   bufferlist xbl;
   if (snapid && is_multiversion()) {
 
diff --git a/src/mds/CInode.h b/src/mds/CInode.h
index af3f79c07e5ab..396b382469941 100644
--- a/src/mds/CInode.h
+++ b/src/mds/CInode.h
@@ -419,7 +419,7 @@ private:
   
 
   // for giving to clients
-  bool encode_inodestat(bufferlist& bl, snapid_t snapid=CEPH_NOSNAP);
+  bool encode_inodestat(bufferlist& bl, snapid_t snapid=CEPH_NOSNAP, bool projected=false);
 
 
   // -- locks --
diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index 863e6808ba78f..62572eabc62a6 100644
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -502,6 +502,28 @@ void Server::reply_request(MDRequest *mdr, int r, CInode *tracei, CDentry *trace
 }
 
 
+void Server::early_reply(MDRequest *mdr, CInode *tracei, CDentry *tracedn)
+{
+  MClientRequest *req = mdr->client_request;
+  entity_inst_t client_inst = req->get_orig_source_inst();
+  if (client_inst.name.is_mds())
+    return;
+
+  MClientReply *reply = new MClientReply(mdr->client_request, 0);
+  reply->set_unsafe();
+
+  dout(10) << "early_reply " << reply->get_result() 
+	   << " (" << strerror(-reply->get_result())
+	   << ") " << *req << dendl;
+
+  snapid_t snapid = CEPH_NOSNAP;
+  CInode *snapdiri = 0;
+  if (tracei || tracedn)
+    set_trace_dist(mdr->session, reply, tracei, tracedn, snapid, snapdiri, true);
+
+  messenger->send_message(reply, client_inst);
+}
+
 /*
  * send given reply
  * include a trace to tracei
@@ -613,7 +635,8 @@ void Server::encode_null_lease(bufferlist& bl)
  * trace is in reverse order (i.e. root inode comes last)
  */
 void Server::set_trace_dist(Session *session, MClientReply *reply, CInode *in, CDentry *dn,
-			    snapid_t snapid, CInode *snapdiri)
+			    snapid_t snapid, CInode *snapdiri,
+			    bool projected)
 {
   // inode, dentry, dir, ..., inode
   bufferlist bl;
@@ -635,7 +658,7 @@ void Server::set_trace_dist(Session *session, MClientReply *reply, CInode *in, C
 
  inode:
   numi++;
-  if (in->encode_inodestat(bl, snapid))
+  if (in->encode_inodestat(bl, snapid, projected))
     lmask = mds->locker->issue_client_lease(in, client, bl, now, session);
   else {
     lmask = CEPH_STAT_MASK_INODE; // immutable bits
@@ -663,12 +686,18 @@ void Server::set_trace_dist(Session *session, MClientReply *reply, CInode *in, C
     dout(10) << " snapdiri at pos " << snapdirpos << dendl;
   }
 
-  if (!dn)
-    dn = in->get_parent_dn();
+  if (!dn) {
+    if (projected)
+      dn = in->get_projected_parent_dn();
+    else
+      dn = in->get_parent_dn();
+  }
   if (!dn) 
     goto done;
 
  dentry:
+  projected = false;
+
   ::encode(dn->get_name(), bl);
   if (snapid == CEPH_NOSNAP)
     lmask = mds->locker->issue_client_lease(dn, client, bl, now, session);
diff --git a/src/mds/Server.h b/src/mds/Server.h
index e08d268a0bfe8..93774693a934f 100644
--- a/src/mds/Server.h
+++ b/src/mds/Server.h
@@ -75,10 +75,12 @@ public:
   void handle_client_request(MClientRequest *m);
 
   void dispatch_client_request(MDRequest *mdr);
+  void early_reply(MDRequest *mdr, CInode *tracei, CDentry *tracedn);
   void reply_request(MDRequest *mdr, int r = 0, CInode *tracei = 0, CDentry *tracedn = 0);
   void reply_request(MDRequest *mdr, MClientReply *reply, CInode *tracei = 0, CDentry *tracedn = 0);
   void set_trace_dist(Session *session, MClientReply *reply, CInode *in, CDentry *dn,
-		      snapid_t snapid, CInode *snapdiri);
+		      snapid_t snapid, CInode *snapdiri,
+		      bool projected = false);
 
   void encode_empty_dirstat(bufferlist& bl);
   void encode_infinite_lease(bufferlist& bl);
diff --git a/src/messages/MClientReply.h b/src/messages/MClientReply.h
index e50a0855140c0..bfabd4a4ec167 100644
--- a/src/messages/MClientReply.h
+++ b/src/messages/MClientReply.h
@@ -190,6 +190,8 @@ public:
   void set_file_caps_mseq(capseq_t s) { st.file_caps_mseq = s; }
   //void set_file_data_version(uint64_t v) { st.file_data_version = v; }
 
+  void set_unsafe() { st.safe = 0; }
+
   MClientReply() {}
   MClientReply(MClientRequest *req, int result = 0) : 
     Message(CEPH_MSG_CLIENT_REPLY) {
-- 
2.39.5