Monitor: introduce a function that translates quorum features into disk features

After an election, we call apply_quorum_to_compatset_features(). It translates
from the quorum features into monitor disk state features we care about and
adds them to the disk store. This prevents an older daemon from starting up
on a store it doesn't understand.

While strictly speaking we don't need to add the EC feature until we create
an EC pool, all monitors which speak the new OSDMap encoding also support EC
pools, and having more than one feature makes the pattern clearer.

Signed-off-by: Greg Farnum <greg@inktank.com>

diff --git a/src/mon/Monitor.cc b/src/mon/Monitor.cc
index b665b83b8bb205164e8c986a12afc4543f78a368..4d396653996832a3d84dff73935e46b55936c37b 100644 (file)
--- a/src/mon/Monitor.cc
+++ b/src/mon/Monitor.cc
@@ -303,6 +303,8 @@ CompatSet Monitor::get_supported_features()
   CompatSet::FeatureSet ceph_mon_feature_incompat;
   ceph_mon_feature_incompat.insert(CEPH_MON_FEATURE_INCOMPAT_BASE);
   ceph_mon_feature_incompat.insert(CEPH_MON_FEATURE_INCOMPAT_SINGLE_PAXOS);
+  ceph_mon_feature_incompat.insert(CEPH_MON_FEATURE_INCOMPAT_OSD_ERASURE_CODES);
+  ceph_mon_feature_incompat.insert(CEPH_MON_FEATURE_INCOMPAT_OSDMAP_ENC);
   return CompatSet(ceph_mon_feature_compat, ceph_mon_feature_ro_compat,
                   ceph_mon_feature_incompat);
 }
@@ -1588,6 +1590,7 @@ void Monitor::lose_election(epoch_t epoch, set<int> &q, int l, uint64_t features
 
 void Monitor::finish_election()
 {
+  apply_quorum_to_compatset_features();
   timecheck_finish();
   exited_quorum = utime_t();
   finish_contexts(g_ceph_context, waitfor_quorum);
@@ -1605,6 +1608,26 @@ void Monitor::finish_election()
   }
 }
 
+void Monitor::apply_quorum_to_compatset_features()
+{
+  CompatSet new_features(features);
+  if (quorum_features & CEPH_FEATURE_OSD_ERASURE_CODES) {
+    new_features.incompat.insert(CEPH_MON_FEATURE_INCOMPAT_OSD_ERASURE_CODES);
+  }
+  if (quorum_features & CEPH_FEATURE_OSDMAP_ENC) {
+    new_features.incompat.insert(CEPH_MON_FEATURE_INCOMPAT_OSDMAP_ENC);
+  }
+
+  if (new_features.compare(features) != 0) {
+    CompatSet diff = features.unsupported(new_features);
+    dout(1) << "Enabling new quorum features: " << diff << dendl;
+    features = new_features;
+    MonitorDBStore::Transaction t;
+    write_features(t);
+    store->apply_transaction(t);
+  }
+}
+
 
 void Monitor::sync_force(Formatter *f, ostream& ss)
 {

diff --git a/src/mon/Monitor.h b/src/mon/Monitor.h
index fcdb7ba977e5c571b12a413a14b1befeca59e426..e7af4429564afa996c74cf4c3471fe240ed41662 100644 (file)
--- a/src/mon/Monitor.h
+++ b/src/mon/Monitor.h
@@ -525,6 +525,7 @@ public:
   uint64_t get_quorum_features() const {
     return quorum_features;
   }
+  void apply_quorum_to_compatset_features();
 
 private:
   void _reset();   ///< called from bootstrap, start_, or join_election
@@ -889,6 +890,9 @@ public:
 #define CEPH_MON_FEATURE_INCOMPAT_BASE CompatSet::Feature (1, "initial feature set (~v.18)")
 #define CEPH_MON_FEATURE_INCOMPAT_GV CompatSet::Feature (2, "global version sequencing (v0.52)")
 #define CEPH_MON_FEATURE_INCOMPAT_SINGLE_PAXOS CompatSet::Feature (3, "single paxos with k/v store (v0.\?)")
+#define CEPH_MON_FEATURE_INCOMPAT_OSD_ERASURE_CODES CompatSet::Feature(4, "support erasure code pools")
+#define CEPH_MON_FEATURE_INCOMPAT_OSDMAP_ENC CompatSet::Feature(5, "new-style osdmap encoding")
+// make sure you add your feature to Monitor::get_supported_features
 
 long parse_pos_long(const char *s, ostream *pss = NULL);