mds: properly set null dentry's first

we should set new null dentry's first when it's created. Otherwise if
the request that creates the new dentry fails, the leftover null dentry
will affect later snap dentry lookup.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

diff --git a/src/mds/Server.cc b/src/mds/Server.cc
index a73843c539553b5fe7b80fde9d7ab45102843bc0..39a4465aa3318b55a02653a990cff6751c2e73d6 100644 (file)
--- a/src/mds/Server.cc
+++ b/src/mds/Server.cc
@@ -2138,6 +2138,8 @@ CDentry* Server::prepare_null_dentry(MDRequestRef& mdr, CDir *dir, const string&
         respond_to_request(mdr, -EEXIST);
         return 0;
       }
+    } else {
+      dn->first = dir->inode->find_snaprealm()->get_newest_seq() + 1;
     }
 
     return dn;
@@ -2151,7 +2153,7 @@ CDentry* Server::prepare_null_dentry(MDRequestRef& mdr, CDir *dir, const string&
   }
   
   // create
-  dn = dir->add_null_dentry(dname);
+  dn = dir->add_null_dentry(dname, dir->inode->find_snaprealm()->get_newest_seq() + 1);
   dn->mark_new();
   dout(10) << "prepare_null_dentry added " << *dn << dendl;
   return dn;
@@ -3065,8 +3067,7 @@ void Server::handle_client_openc(MDRequestRef& mdr)
   }
   in->inode.rstat.rfiles = 1;
 
-  if (follows >= dn->first)
-    dn->first = follows+1;
+  assert(dn->first == follows+1);
   in->first = dn->first;
   
   // prepare finisher
@@ -4306,10 +4307,9 @@ class C_MDS_mknod_finish : public MDSInternalContext {
   MDRequestRef mdr;
   CDentry *dn;
   CInode *newi;
-  snapid_t follows;
 public:
-  C_MDS_mknod_finish(MDS *m, MDRequestRef& r, CDentry *d, CInode *ni, snapid_t f) :
-    MDSInternalContext(m), mdr(r), dn(d), newi(ni), follows(f) {}
+  C_MDS_mknod_finish(MDS *m, MDRequestRef& r, CDentry *d, CInode *ni) :
+    MDSInternalContext(m), mdr(r), dn(d), newi(ni) {}
   void finish(int r) {
     assert(r == 0);
 
@@ -4417,8 +4417,7 @@ void Server::handle_client_mknod(MDRequestRef& mdr)
     }
   }
 
-  if (follows >= dn->first)
-    dn->first = follows + 1;
+  assert(dn->first == follows + 1);
   newi->first = dn->first;
     
   dout(10) << "mknod mode " << newi->inode.mode << " rdev " << newi->inode.rdev << dendl;
@@ -4434,7 +4433,7 @@ void Server::handle_client_mknod(MDRequestRef& mdr)
                                    PREDIRTY_PRIMARY|PREDIRTY_DIR, 1);
   le->metablob.add_primary_dentry(dn, newi, true, true, true);
 
-  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi, follows));
+  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi));
 }
 
 
@@ -4474,8 +4473,7 @@ void Server::handle_client_mkdir(MDRequestRef& mdr)
   newi->inode.update_backtrace();
 
   dout(12) << " follows " << follows << dendl;
-  if (follows >= dn->first)
-    dn->first = follows + 1;
+  assert(dn->first == follows + 1);
   newi->first = dn->first;
 
   // ...and that new dir is empty.
@@ -4512,7 +4510,7 @@ void Server::handle_client_mkdir(MDRequestRef& mdr)
   LogSegment *ls = mds->mdlog->get_current_segment();
   ls->open_files.push_back(&newi->item_open_file);
 
-  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi, follows));
+  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi));
 }
 
 
@@ -4533,8 +4531,6 @@ void Server::handle_client_symlink(MDRequestRef& mdr)
   if (!mds->locker->acquire_locks(mdr, rdlocks, wrlocks, xlocks))
     return;
 
-  snapid_t follows = dn->get_dir()->inode->find_snaprealm()->get_newest_seq();
-
   unsigned mode = S_IFLNK | 0777;
   CInode *newi = prepare_new_inode(mdr, dn->get_dir(), inodeno_t(req->head.ino), mode);
   assert(newi);
@@ -4549,8 +4545,6 @@ void Server::handle_client_symlink(MDRequestRef& mdr)
   newi->inode.version = dn->pre_dirty();
   newi->inode.update_backtrace();
 
-  if (follows >= dn->first)
-    dn->first = follows + 1;
   newi->first = dn->first;
 
   // prepare finisher
@@ -4562,7 +4556,7 @@ void Server::handle_client_symlink(MDRequestRef& mdr)
   mdcache->predirty_journal_parents(mdr, &le->metablob, newi, dn->get_dir(), PREDIRTY_PRIMARY|PREDIRTY_DIR, 1);
   le->metablob.add_primary_dentry(dn, newi, true, true);
 
-  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi, follows));
+  journal_and_reply(mdr, newi, dn, le, new C_MDS_mknod_finish(mds, mdr, dn, newi));
 }
 
 
@@ -4649,10 +4643,6 @@ void Server::_link_local(MDRequestRef& mdr, CDentry *dn, CInode *targeti)
   pi->ctime = mdr->get_op_stamp();
   pi->version = tipv;
 
-  snapid_t follows = dn->get_dir()->inode->find_snaprealm()->get_newest_seq();
-  if (follows >= dn->first)
-    dn->first = follows;
-
   // log + wait
   EUpdate *le = new EUpdate(mdlog, "link_local");
   mdlog->start_entry(le);