Lock tweaks.

Author: ncruces

vfs/memdb/memdb.go

@@ -223,7 +223,7 @@ func (m *memFile) Lock(lock vfs.LockLevel) error {
 		m.reserved = true
 
 	case vfs.LOCK_EXCLUSIVE:
-		if m.lock < vfs.LOCK_PENDING {
+		if m.lock == vfs.LOCK_RESERVED {
 			m.lock = vfs.LOCK_PENDING
 			m.pending = true
 		}

vfs/mvcc/mvcc.go

@@ -287,7 +287,9 @@ func (m *mvccFile) Unlock(lock vfs.LockLevel) error {
 	// Relase ownership, commit changes.
 	if m.owner == m {
 		m.owner = nil
-		m.mvccDB.data = m.data
+		if m.lock == vfs.LOCK_EXCLUSIVE {
+			m.mvccDB.data = m.data
+		}
 		if m.waiter != nil {
 			m.waiter.Broadcast()
 		}