osd_types: add excl obc lock

Signed-off-by: Samuel Just <sjust@redhat.com>

src/osd/osd_types.h

@@ -2996,13 +2996,15 @@ public:
     enum State {
       RWNONE,
       RWREAD,
-      RWWRITE
+      RWWRITE,
+      RWEXCL,
     };
     static const char *get_state_name(State s) {
       switch (s) {
       case RWNONE: return "none";
       case RWREAD: return "read";
       case RWWRITE: return "write";
+      case RWEXCL: return "excl";
       default: return "???";
       }
     }
@@ -3049,6 +3051,8 @@ public:
 	return true;
       case RWWRITE:
 	return false;
+      case RWEXCL:
+	return false;
       default:
 	assert(0 == "unhandled case");
 	return false;
@@ -3081,11 +3085,39 @@ public:
 	return true;
       case RWREAD:
 	return false;
+      case RWEXCL:
+	return false;
       default:
 	assert(0 == "unhandled case");
 	return false;
       }
     }
+    bool get_excl_lock() {
+      switch (state) {
+      case RWNONE:
+	assert(count == 0);
+	state = RWEXCL;
+	count = 1;
+	return true;
+      case RWWRITE:
+	return false;
+      case RWREAD:
+	return false;
+      case RWEXCL:
+	return false;
+      default:
+	assert(0 == "unhandled case");
+	return false;
+      }
+    }
+    bool get_excl(OpRequestRef op) {
+      if (get_excl_lock()) {
+	return true;
+      } // else
+      if (op)
+	waiters.push_back(op);
+      return false;
+    }
     /// same as get_write_lock, but ignore starvation
     bool take_write_lock() {
       if (state == RWWRITE) {
@@ -3111,6 +3143,10 @@ public:
       assert(state == RWWRITE);
       dec(requeue);
     }
+    void put_excl(list<OpRequestRef> *requeue) {
+      assert(state == RWEXCL);
+      dec(requeue);
+    }
     bool empty() const { return state == RWNONE; }
   } rwstate;
 
@@ -3120,6 +3156,22 @@ public:
   bool get_write(OpRequestRef op) {
     return rwstate.get_write(op, false);
   }
+  bool get_excl(OpRequestRef op) {
+    return rwstate.get_excl(op);
+  }
+  bool get_lock_type(OpRequestRef op, RWState::State type) {
+    switch (type) {
+    case RWState::RWWRITE:
+      return get_write(op);
+    case RWState::RWREAD:
+      return get_read(op);
+    case RWState::RWEXCL:
+      return get_excl(op);
+    default:
+      assert(0 == "invalid lock type");
+      return true;
+    }
+  }
   bool get_write_greedy(OpRequestRef op) {
     return rwstate.get_write(op, true);
   }
@@ -3146,6 +3198,19 @@ public:
   void put_read(list<OpRequestRef> *to_wake) {
     rwstate.put_read(to_wake);
   }
+  void put_excl(list<OpRequestRef> *to_wake,
+		 bool *requeue_recovery,
+		 bool *requeue_snaptrimmer) {
+    rwstate.put_excl(to_wake);
+    if (rwstate.empty() && rwstate.recovery_read_marker) {
+      rwstate.recovery_read_marker = false;
+      *requeue_recovery = true;
+    }
+    if (rwstate.empty() && rwstate.snaptrimmer_write_marker) {
+      rwstate.snaptrimmer_write_marker = false;
+      *requeue_snaptrimmer = true;
+    }
+  }
   void put_write(list<OpRequestRef> *to_wake,
 		 bool *requeue_recovery,
 		 bool *requeue_snaptrimmer) {