mds: Save straydn in mdr so it's consistent across retry attempts.

Otherwise, we could choose new stray dirs and fail to get all
the locks we needed (while leaving old strays locked forever!).

Signed-off-by: Greg Farnum <gregf@hq.newdream.net>

diff --git a/src/mds/MDCache.h b/src/mds/MDCache.h
index 957dceb2273e9724dcb493adac108f66bfbc7866..7b2b94998e5c32abccf40ec9c7739547dc2eda9c 100644 (file)
--- a/src/mds/MDCache.h
+++ b/src/mds/MDCache.h
@@ -259,6 +259,7 @@ struct MDRequest : public Mutation {
 
   // store up to two sets of dn vectors, inode pointers, for request path1 and path2.
   vector<CDentry*> dn[2];
+  CDentry *straydn;
   CInode *in[2];
   snapid_t snapid;
 
@@ -323,7 +324,7 @@ struct MDRequest : public Mutation {
   MDRequest() : 
     ref(1),
     session(0), item_session_request(this),
-    client_request(0), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
+    client_request(0), straydn(NULL), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
     alloc_ino(0), used_prealloc_ino(0), snap_caps(0), did_early_reply(false),
     slave_request(0),
     internal_op(-1),
@@ -334,7 +335,7 @@ struct MDRequest : public Mutation {
     Mutation(ri),
     ref(1),
     session(0), item_session_request(this),
-    client_request(req), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
+    client_request(req), straydn(NULL), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
     alloc_ino(0), used_prealloc_ino(0), snap_caps(0), did_early_reply(false),
     slave_request(0),
     internal_op(-1),
@@ -345,7 +346,7 @@ struct MDRequest : public Mutation {
     Mutation(ri, by),
     ref(1),
     session(0), item_session_request(this),
-    client_request(0), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
+    client_request(0), straydn(NULL), snapid(CEPH_NOSNAP), tracei(0), tracedn(0),
     alloc_ino(0), used_prealloc_ino(0), snap_caps(0), did_early_reply(false),
     slave_request(0),
     internal_op(-1),

diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index 35af027dc6ea294f7e0b079f2a5b0db458b98102..c02526ac5e226777e856cef3801babc8a30a07fb 100644 (file)
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -4045,12 +4045,16 @@ void Server::handle_client_unlink(MDRequest *mdr)
     }
   }
 
-  CDentry *straydn = 0;
-  if (dnl->is_primary()) {
+  // -- create stray dentry? --
+  CDentry *straydn = mdr->straydn;
+  if (dnl->is_primary() && !straydn) {
     straydn = mdcache->get_or_create_stray_dentry(dnl->get_inode());
-    mdr->pin(straydn);  // pin it.
-    dout(10) << " straydn is " << *straydn << dendl;
+    mdr->pin(straydn);
+    mdr->straydn = straydn;
   }
+  if (straydn)
+    dout(10) << " straydn is " << *straydn << dendl;
+
 
   // lock
   set<SimpleLock*> rdlocks, wrlocks, xlocks;
@@ -4499,12 +4503,14 @@ void Server::handle_client_rename(MDRequest *mdr)
     dout(10) << " this is a link merge" << dendl;
 
   // -- create stray dentry? --
-  CDentry *straydn = 0;
-  if (destdnl->is_primary() && !linkmerge) {
+  CDentry *straydn = mdr->straydn;
+  if (destdnl->is_primary() && !linkmerge && !straydn) {
     straydn = mdcache->get_or_create_stray_dentry(destdnl->get_inode());
     mdr->pin(straydn);
-    dout(10) << "straydn is " << *straydn << dendl;
+    mdr->straydn = straydn;
   }
+  if (straydn)
+    dout(10) << " straydn is " << *straydn << dendl;
 
   // -- prepare witness list --
   /*