From: Sage Weil <sage@newdream.net>
Date: Tue, 21 Sep 2010 02:59:00 +0000 (-0700)
Subject: mds: don't instantiate null dentries for snapped namespace
X-Git-Tag: v0.22~143^2~2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=fa277aef7bb4c8ec31963e40114546b2377d65b4;p=ceph.git

mds: don't instantiate null dentries for snapped namespace

The dentry needs a [first,last] range and we don't know what first is when
we miss a lookup.  And part of the point of instantiating null dentires is
to issue leases against them, which we don't do.  The client will cache
the null result.
---

diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index 0141c7b73850..83b41eaa7e48 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -6008,12 +6008,14 @@ int MDCache::path_traverse(MDRequest *mdr, Message *req,     // who
 	  if (dn) {
 	    dout(20) << " had null " << *dn << dendl;
 	    assert(dnl->is_null());
-	  } else if (!curdir->is_frozen()) {
+	  } else if (curdir->is_frozen()) {
+	    dout(20) << " not adding null to frozen dir " << dendl;
+	  } else if (snapid < CEPH_MAXSNAP) {
+	    dout(20) << " not adding null for snapid " << snapid << dendl;
+	  } else {
 	    // create a null dentry
 	    dn = curdir->add_null_dentry(path[depth]);
 	    dout(20) << " added null " << *dn << dendl;
-	  } else {
-	    dout(20) << " not adding null to frozen dir " << dendl;
 	  }
 	  if (dn)
 	    pdnvec->push_back(dn);