From: Kefu Chai <kchai@redhat.com>
Date: Fri, 30 Aug 2019 06:03:06 +0000 (+0800)
Subject: mon: use get_req<> instead of static_cast<>(get_req())
X-Git-Tag: v15.1.0~1652^2~1
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=25d78984f7acc8908c5895bbe23d2bd7bfbbdb51;p=ceph.git

mon: use get_req<> instead of static_cast<>(get_req())

less repeating, better readability

Signed-off-by: Kefu Chai <kchai@redhat.com>
---

diff --git a/src/mon/AuthMonitor.cc b/src/mon/AuthMonitor.cc
index 4025a926ee5..e7fa856dd46 100644
--- a/src/mon/AuthMonitor.cc
+++ b/src/mon/AuthMonitor.cc
@@ -464,7 +464,7 @@ version_t AuthMonitor::get_trim_to() const
 
 bool AuthMonitor::preprocess_query(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(10) << "preprocess_query " << *m << " from " << m->get_orig_source_inst() << dendl;
   switch (m->get_type()) {
   case MSG_MON_COMMAND:
@@ -490,7 +490,7 @@ bool AuthMonitor::preprocess_query(MonOpRequestRef op)
 
 bool AuthMonitor::prepare_update(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(10) << "prepare_update " << *m << " from " << m->get_orig_source_inst() << dendl;
   switch (m->get_type()) {
   case MSG_MON_COMMAND:
@@ -569,7 +569,7 @@ uint64_t AuthMonitor::assign_global_id(bool should_increase_max)
 
 bool AuthMonitor::prep_auth(MonOpRequestRef op, bool paxos_writable)
 {
-  MAuth *m = static_cast<MAuth*>(op->get_req());
+  auto m = op->get_req<MAuth>();
   dout(10) << "prep_auth() blob_size=" << m->get_auth_payload().length() << dendl;
 
   MonSession *s = op->get_session();
@@ -757,7 +757,7 @@ done:
 
 bool AuthMonitor::preprocess_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = -1;
   bufferlist rdata;
   stringstream ss, ds;
@@ -1282,7 +1282,7 @@ bool AuthMonitor::valid_caps(const vector<string>& caps, ostream *out)
 
 bool AuthMonitor::prepare_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   stringstream ss, ds;
   bufferlist rdata;
   string rs;
diff --git a/src/mon/ConfigMonitor.cc b/src/mon/ConfigMonitor.cc
index 45704cb4550..c1814b28eb8 100644
--- a/src/mon/ConfigMonitor.cc
+++ b/src/mon/ConfigMonitor.cc
@@ -134,7 +134,7 @@ static string indent_who(const string& who)
 
 bool ConfigMonitor::preprocess_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   std::stringstream ss;
   int err = 0;
 
@@ -412,7 +412,7 @@ bool ConfigMonitor::preprocess_command(MonOpRequestRef op)
 
 void ConfigMonitor::handle_get_config(MonOpRequestRef op)
 {
-  MGetConfig *m = static_cast<MGetConfig*>(op->get_req());
+  auto m = op->get_req<MGetConfig>();
   dout(10) << __func__ << " " << m->name << " host " << m->host << dendl;
 
   const OSDMap& osdmap = mon->osdmon()->osdmap;
@@ -447,7 +447,7 @@ bool ConfigMonitor::prepare_update(MonOpRequestRef op)
 
 bool ConfigMonitor::prepare_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   std::stringstream ss;
   int err = -EINVAL;
 
diff --git a/src/mon/Elector.cc b/src/mon/Elector.cc
index 754e4049955..403fbca0fcc 100644
--- a/src/mon/Elector.cc
+++ b/src/mon/Elector.cc
@@ -212,7 +212,7 @@ void Elector::message_victory(const std::set<int>& quorum)
 void Elector::handle_propose(MonOpRequestRef op)
 {
   op->mark_event("elector:handle_propose");
-  MMonElection *m = static_cast<MMonElection*>(op->get_req());
+  auto m = op->get_req<MMonElection>();
   dout(5) << "handle_propose from " << m->get_source() << dendl;
   int from = m->get_source().num();
 
@@ -253,7 +253,7 @@ void Elector::handle_propose(MonOpRequestRef op)
 void Elector::handle_ack(MonOpRequestRef op)
 {
   op->mark_event("elector:handle_ack");
-  MMonElection *m = static_cast<MMonElection*>(op->get_req());
+  auto m = op->get_req<MMonElection>();
   dout(5) << "handle_ack from " << m->get_source() << dendl;
   int from = m->get_source().num();
 
@@ -302,7 +302,7 @@ void Elector::handle_ack(MonOpRequestRef op)
 void Elector::handle_victory(MonOpRequestRef op)
 {
   op->mark_event("elector:handle_victory");
-  MMonElection *m = static_cast<MMonElection*>(op->get_req());
+  auto m = op->get_req<MMonElection>();
   dout(5) << "handle_victory from " << m->get_source()
           << " quorum_features " << m->quorum_features
           << " " << m->mon_features
@@ -332,7 +332,7 @@ void Elector::handle_victory(MonOpRequestRef op)
 void Elector::nak_old_peer(MonOpRequestRef op)
 {
   op->mark_event("elector:nak_old_peer");
-  MMonElection *m = static_cast<MMonElection*>(op->get_req());
+  auto m = op->get_req<MMonElection>();
   uint64_t supported_features = m->get_connection()->get_features();
   uint64_t required_features = mon->get_required_features();
   mon_feature_t required_mon_features = mon->get_required_mon_features();
@@ -354,7 +354,7 @@ void Elector::nak_old_peer(MonOpRequestRef op)
 void Elector::handle_nak(MonOpRequestRef op)
 {
   op->mark_event("elector:handle_nak");
-  MMonElection *m = static_cast<MMonElection*>(op->get_req());
+  auto m = op->get_req<MMonElection>();
   dout(1) << "handle_nak from " << m->get_source()
 	  << " quorum_features " << m->quorum_features
           << " " << m->mon_features
@@ -399,7 +399,7 @@ void Elector::dispatch(MonOpRequestRef op)
 	return;
       }
 
-      MMonElection *em = static_cast<MMonElection*>(op->get_req());
+      auto em = op->get_req<MMonElection>();
 
       // assume an old message encoding would have matched
       if (em->fsid != mon->monmap->fsid) {
diff --git a/src/mon/HealthMonitor.cc b/src/mon/HealthMonitor.cc
index c6029b415d3..ca038a05565 100644
--- a/src/mon/HealthMonitor.cc
+++ b/src/mon/HealthMonitor.cc
@@ -167,7 +167,7 @@ version_t HealthMonitor::get_trim_to() const
 
 bool HealthMonitor::preprocess_query(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
   case MSG_MON_COMMAND:
     return preprocess_command(op);
@@ -197,7 +197,7 @@ bool HealthMonitor::prepare_update(MonOpRequestRef op)
 
 bool HealthMonitor::preprocess_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   std::stringstream ss;
   bufferlist rdata;
 
@@ -229,7 +229,7 @@ bool HealthMonitor::preprocess_command(MonOpRequestRef op)
 
 bool HealthMonitor::prepare_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
 
   std::stringstream ss;
   bufferlist rdata;
@@ -330,7 +330,7 @@ out:
 
 bool HealthMonitor::prepare_health_checks(MonOpRequestRef op)
 {
-  MMonHealthChecks *m = static_cast<MMonHealthChecks*>(op->get_req());
+  auto m = op->get_req<MMonHealthChecks>();
   // no need to check if it's changed, the peon has done so
   quorum_checks[m->get_source().num()] = std::move(m->health_checks);
   return true;
diff --git a/src/mon/LogMonitor.cc b/src/mon/LogMonitor.cc
index 087f5800826..7be118d0ed8 100644
--- a/src/mon/LogMonitor.cc
+++ b/src/mon/LogMonitor.cc
@@ -256,7 +256,7 @@ version_t LogMonitor::get_trim_to() const
 bool LogMonitor::preprocess_query(MonOpRequestRef op)
 {
   op->mark_logmon_event("preprocess_query");
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(10) << "preprocess_query " << *m << " from " << m->get_orig_source_inst() << dendl;
   switch (m->get_type()) {
   case MSG_MON_COMMAND:
@@ -280,7 +280,7 @@ bool LogMonitor::preprocess_query(MonOpRequestRef op)
 bool LogMonitor::prepare_update(MonOpRequestRef op)
 {
   op->mark_logmon_event("prepare_update");
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(10) << "prepare_update " << *m << " from " << m->get_orig_source_inst() << dendl;
   switch (m->get_type()) {
   case MSG_MON_COMMAND:
@@ -302,7 +302,7 @@ bool LogMonitor::prepare_update(MonOpRequestRef op)
 bool LogMonitor::preprocess_log(MonOpRequestRef op)
 {
   op->mark_logmon_event("preprocess_log");
-  MLog *m = static_cast<MLog*>(op->get_req());
+  auto m = op->get_req<MLog>();
   dout(10) << "preprocess_log " << *m << " from " << m->get_orig_source() << dendl;
   int num_new = 0;
 
@@ -348,7 +348,7 @@ struct LogMonitor::C_Log : public C_MonOp {
 bool LogMonitor::prepare_log(MonOpRequestRef op) 
 {
   op->mark_logmon_event("prepare_log");
-  MLog *m = static_cast<MLog*>(op->get_req());
+  auto m = op->get_req<MLog>();
   dout(10) << "prepare_log " << *m << " from " << m->get_orig_source() << dendl;
 
   if (m->fsid != mon->monmap->fsid) {
@@ -373,7 +373,7 @@ bool LogMonitor::prepare_log(MonOpRequestRef op)
 
 void LogMonitor::_updated_log(MonOpRequestRef op)
 {
-  MLog *m = static_cast<MLog*>(op->get_req());
+  auto m = op->get_req<MLog>();
   dout(7) << "_updated_log for " << m->get_orig_source_inst() << dendl;
   mon->send_reply(op, new MLogAck(m->fsid, m->entries.rbegin()->seq));
 }
@@ -393,7 +393,7 @@ bool LogMonitor::should_propose(double& delay)
 bool LogMonitor::preprocess_command(MonOpRequestRef op)
 {
   op->mark_logmon_event("preprocess_command");
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = -EINVAL;
   bufferlist rdata;
   stringstream ss;
@@ -546,7 +546,7 @@ bool LogMonitor::preprocess_command(MonOpRequestRef op)
 bool LogMonitor::prepare_command(MonOpRequestRef op)
 {
   op->mark_logmon_event("prepare_command");
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   stringstream ss;
   string rs;
   int err = -EINVAL;
diff --git a/src/mon/MDSMonitor.cc b/src/mon/MDSMonitor.cc
index c51eb850b6c..2cad13dac53 100644
--- a/src/mon/MDSMonitor.cc
+++ b/src/mon/MDSMonitor.cc
@@ -278,7 +278,7 @@ version_t MDSMonitor::get_trim_to() const
 bool MDSMonitor::preprocess_query(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(10) << "preprocess_query " << *m << " from " << m->get_orig_source()
 	   << " " << m->get_orig_source_addrs() << dendl;
 
@@ -319,7 +319,7 @@ void MDSMonitor::_note_beacon(MMDSBeacon *m)
 bool MDSMonitor::preprocess_beacon(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  MMDSBeacon *m = static_cast<MMDSBeacon*>(op->get_req());
+  auto m = op->get_req<MMDSBeacon>();
   MDSMap::DaemonState state = m->get_state();
   mds_gid_t gid = m->get_global_id();
   version_t seq = m->get_seq();
@@ -472,7 +472,7 @@ bool MDSMonitor::preprocess_beacon(MonOpRequestRef op)
 bool MDSMonitor::preprocess_offload_targets(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  MMDSLoadTargets *m = static_cast<MMDSLoadTargets*>(op->get_req());
+  auto m = op->get_req<MMDSLoadTargets>();
   dout(10) << "preprocess_offload_targets " << *m << " from " << m->get_orig_source() << dendl;
 
   const auto &fsmap = get_fsmap();
@@ -502,7 +502,7 @@ bool MDSMonitor::preprocess_offload_targets(MonOpRequestRef op)
 bool MDSMonitor::prepare_update(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(7) << "prepare_update " << *m << dendl;
 
   switch (m->get_type()) {
@@ -532,7 +532,7 @@ bool MDSMonitor::prepare_update(MonOpRequestRef op)
 bool MDSMonitor::prepare_beacon(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  MMDSBeacon *m = static_cast<MMDSBeacon*>(op->get_req());
+  auto m = op->get_req<MMDSBeacon>();
   // -- this is an update --
   dout(12) << "prepare_beacon " << *m << " from " << m->get_orig_source()
 	   << " " << m->get_orig_source_addrs() << dendl;
@@ -796,7 +796,7 @@ bool MDSMonitor::prepare_offload_targets(MonOpRequestRef op)
   auto &pending = get_pending_fsmap_writeable();
 
   op->mark_mdsmon_event(__func__);
-  MMDSLoadTargets *m = static_cast<MMDSLoadTargets*>(op->get_req());
+  auto m = op->get_req<MMDSLoadTargets>();
   mds_gid_t gid = m->global_id;
   if (pending.gid_has_rank(gid)) {
     dout(10) << "prepare_offload_targets " << gid << " " << m->targets << dendl;
@@ -818,7 +818,7 @@ void MDSMonitor::_updated(MonOpRequestRef op)
 {
   const auto &fsmap = get_fsmap();
   op->mark_mdsmon_event(__func__);
-  MMDSBeacon *m = static_cast<MMDSBeacon*>(op->get_req());
+  auto m = op->get_req<MMDSBeacon>();
   dout(10) << "_updated " << m->get_orig_source() << " " << *m << dendl;
   mon->clog->debug() << m->get_orig_source() << " "
 		     << m->get_orig_source_addrs() << " "
@@ -861,7 +861,7 @@ void MDSMonitor::dump_info(Formatter *f)
 bool MDSMonitor::preprocess_command(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = -1;
   bufferlist rdata;
   stringstream ss, ds;
@@ -1230,7 +1230,7 @@ int MDSMonitor::fail_mds(FSMap &fsmap, std::ostream &ss,
 bool MDSMonitor::prepare_command(MonOpRequestRef op)
 {
   op->mark_mdsmon_event(__func__);
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = -EINVAL;
   stringstream ss;
   bufferlist rdata;
diff --git a/src/mon/MgrMonitor.cc b/src/mon/MgrMonitor.cc
index eabae5a11c5..8b5f25f80fa 100644
--- a/src/mon/MgrMonitor.cc
+++ b/src/mon/MgrMonitor.cc
@@ -365,7 +365,7 @@ bool MgrMonitor::check_caps(MonOpRequestRef op, const uuid_d& fsid)
 
 bool MgrMonitor::preprocess_query(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
     case MSG_MGR_BEACON:
       return preprocess_beacon(op);
@@ -387,7 +387,7 @@ bool MgrMonitor::preprocess_query(MonOpRequestRef op)
 
 bool MgrMonitor::prepare_update(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
     case MSG_MGR_BEACON:
       return prepare_beacon(op);
@@ -429,7 +429,7 @@ public:
 
 bool MgrMonitor::preprocess_beacon(MonOpRequestRef op)
 {
-  MMgrBeacon *m = static_cast<MMgrBeacon*>(op->get_req());
+  auto m = op->get_req<MMgrBeacon>();
   mon->no_reply(op); // we never reply to beacons
   dout(4) << "beacon from " << m->get_gid() << dendl;
 
@@ -444,7 +444,7 @@ bool MgrMonitor::preprocess_beacon(MonOpRequestRef op)
 
 bool MgrMonitor::prepare_beacon(MonOpRequestRef op)
 {
-  MMgrBeacon *m = static_cast<MMgrBeacon*>(op->get_req());
+  auto m = op->get_req<MMgrBeacon>();
   dout(4) << "beacon from " << m->get_gid() << dendl;
 
   // See if we are seeing same name, new GID for the active daemon
@@ -843,7 +843,7 @@ void MgrMonitor::drop_standby(uint64_t gid, bool drop_meta)
 
 bool MgrMonitor::preprocess_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   std::stringstream ss;
   bufferlist rdata;
 
@@ -982,7 +982,7 @@ reply:
 
 bool MgrMonitor::prepare_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
 
   std::stringstream ss;
   bufferlist rdata;
diff --git a/src/mon/MgrStatMonitor.cc b/src/mon/MgrStatMonitor.cc
index 2668ff721b0..d4e12523b8d 100644
--- a/src/mon/MgrStatMonitor.cc
+++ b/src/mon/MgrStatMonitor.cc
@@ -154,7 +154,7 @@ void MgrStatMonitor::tick()
 
 bool MgrStatMonitor::preprocess_query(MonOpRequestRef op)
 {
-  auto m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
   case CEPH_MSG_STATFS:
     return preprocess_statfs(op);
@@ -171,7 +171,7 @@ bool MgrStatMonitor::preprocess_query(MonOpRequestRef op)
 
 bool MgrStatMonitor::prepare_update(MonOpRequestRef op)
 {
-  auto m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
   case MSG_MON_MGR_REPORT:
     return prepare_report(op);
@@ -190,7 +190,7 @@ bool MgrStatMonitor::preprocess_report(MonOpRequestRef op)
 
 bool MgrStatMonitor::prepare_report(MonOpRequestRef op)
 {
-  auto m = static_cast<MMonMgrReport*>(op->get_req());
+  auto m = op->get_req<MMonMgrReport>();
   bufferlist bl = m->get_data();
   auto p = bl.cbegin();
   decode(pending_digest, p);
@@ -231,7 +231,7 @@ bool MgrStatMonitor::prepare_report(MonOpRequestRef op)
 bool MgrStatMonitor::preprocess_getpoolstats(MonOpRequestRef op)
 {
   op->mark_pgmon_event(__func__);
-  auto m = static_cast<MGetPoolStats*>(op->get_req());
+  auto m = op->get_req<MGetPoolStats>();
   auto session = op->get_session();
   if (!session)
     return true;
@@ -264,7 +264,7 @@ bool MgrStatMonitor::preprocess_getpoolstats(MonOpRequestRef op)
 bool MgrStatMonitor::preprocess_statfs(MonOpRequestRef op)
 {
   op->mark_pgmon_event(__func__);
-  auto statfs = static_cast<MStatfs*>(op->get_req());
+  auto statfs = op->get_req<MStatfs>();
   auto session = op->get_session();
 
   if (!session)
diff --git a/src/mon/Monitor.cc b/src/mon/Monitor.cc
index 0d36fb1b091..d4c0a94e1b5 100644
--- a/src/mon/Monitor.cc
+++ b/src/mon/Monitor.cc
@@ -1495,7 +1495,7 @@ void Monitor::sync_finish(version_t last_committed)
 
 void Monitor::handle_sync(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   dout(10) << __func__ << " " << *m << dendl;
   switch (m->op) {
 
@@ -1533,14 +1533,14 @@ void Monitor::handle_sync(MonOpRequestRef op)
 
 void Monitor::_sync_reply_no_cookie(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   MMonSync *reply = new MMonSync(MMonSync::OP_NO_COOKIE, m->cookie);
   m->get_connection()->send_message(reply);
 }
 
 void Monitor::handle_sync_get_cookie(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   if (is_synchronizing()) {
     _sync_reply_no_cookie(op);
     return;
@@ -1593,7 +1593,7 @@ void Monitor::handle_sync_get_cookie(MonOpRequestRef op)
 
 void Monitor::handle_sync_get_chunk(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   dout(10) << __func__ << " " << *m << dendl;
 
   if (sync_providers.count(m->cookie) == 0) {
@@ -1664,7 +1664,7 @@ void Monitor::handle_sync_get_chunk(MonOpRequestRef op)
 
 void Monitor::handle_sync_cookie(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   dout(10) << __func__ << " " << *m << dendl;
   if (sync_cookie) {
     dout(10) << __func__ << " already have a cookie, ignoring" << dendl;
@@ -1698,7 +1698,7 @@ void Monitor::sync_get_next_chunk()
 
 void Monitor::handle_sync_chunk(MonOpRequestRef op)
 {
-  MMonSync *m = static_cast<MMonSync*>(op->get_req());
+  auto m = op->get_req<MMonSync>();
   dout(10) << __func__ << " " << *m << dendl;
 
   if (m->cookie != sync_cookie) {
@@ -1814,7 +1814,7 @@ void Monitor::probe_timeout(int r)
 
 void Monitor::handle_probe(MonOpRequestRef op)
 {
-  MMonProbe *m = static_cast<MMonProbe*>(op->get_req());
+  auto m = op->get_req<MMonProbe>();
   dout(10) << "handle_probe " << *m << dendl;
 
   if (m->fsid != monmap->fsid) {
@@ -1844,7 +1844,7 @@ void Monitor::handle_probe(MonOpRequestRef op)
 
 void Monitor::handle_probe_probe(MonOpRequestRef op)
 {
-  MMonProbe *m = static_cast<MMonProbe*>(op->get_req());
+  auto m = op->get_req<MMonProbe>();
 
   dout(10) << "handle_probe_probe " << m->get_source_inst() << *m
 	   << " features " << m->get_connection()->get_features() << dendl;
@@ -1902,7 +1902,7 @@ void Monitor::handle_probe_probe(MonOpRequestRef op)
 
 void Monitor::handle_probe_reply(MonOpRequestRef op)
 {
-  MMonProbe *m = static_cast<MMonProbe*>(op->get_req());
+  auto m = op->get_req<MMonProbe>();
   dout(10) << "handle_probe_reply " << m->get_source_inst()
 	   << " " << *m << dendl;
   dout(10) << " monmap is " << *monmap << dendl;
@@ -3124,7 +3124,7 @@ struct C_MgrProxyCommand : public Context {
 void Monitor::handle_command(MonOpRequestRef op)
 {
   ceph_assert(op->is_type_command());
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   if (m->fsid != monmap->fsid) {
     dout(0) << "handle_command on fsid " << m->fsid << " != " << monmap->fsid << dendl;
     reply_command(op, -EPERM, "wrong fsid", 0);
@@ -3923,7 +3923,7 @@ void Monitor::reply_command(MonOpRequestRef op, int rc, const string &rs, versio
 void Monitor::reply_command(MonOpRequestRef op, int rc, const string &rs,
                             bufferlist& rdata, version_t version)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   ceph_assert(m->get_type() == MSG_MON_COMMAND);
   MMonCommandAck *reply = new MMonCommandAck(m->cmd, rc, rs, version);
   reply->set_tid(m->get_tid());
@@ -4013,7 +4013,7 @@ struct AnonConnection : public Connection {
 //extract the original message and put it into the regular dispatch function
 void Monitor::handle_forward(MonOpRequestRef op)
 {
-  MForward *m = static_cast<MForward*>(op->get_req());
+  auto m = op->get_req<MForward>();
   dout(10) << "received forwarded message from "
 	   << ceph_entity_type_name(m->client_type)
 	   << " " << m->client_addrs
@@ -4130,7 +4130,7 @@ void Monitor::no_reply(MonOpRequestRef op)
 
 void Monitor::handle_route(MonOpRequestRef op)
 {
-  MRoute *m = static_cast<MRoute*>(op->get_req());
+  auto m = op->get_req<MRoute>();
   MonSession *session = op->get_session();
   //check privileges
   if (!session->is_capable("mon", MON_CAP_X)) {
@@ -4562,7 +4562,7 @@ void Monitor::dispatch_op(MonOpRequestRef op)
     case MSG_MON_PAXOS:
       {
         op->set_type_paxos();
-        MMonPaxos *pm = static_cast<MMonPaxos*>(op->get_req());
+        auto pm = op->get_req<MMonPaxos>();
         if (!op->get_session()->is_capable("mon", MON_CAP_X)) {
           //can't send these!
           return;
@@ -4629,7 +4629,7 @@ void Monitor::dispatch_op(MonOpRequestRef op)
 
 void Monitor::handle_ping(MonOpRequestRef op)
 {
-  MPing *m = static_cast<MPing*>(op->get_req());
+  auto m = op->get_req<MPing>();
   dout(10) << __func__ << " " << *m << dendl;
   MPing *reply = new MPing;
   bufferlist payload;
@@ -4904,7 +4904,7 @@ health_status_t Monitor::timecheck_status(ostringstream &ss,
 
 void Monitor::handle_timecheck_leader(MonOpRequestRef op)
 {
-  MTimeCheck2 *m = static_cast<MTimeCheck2*>(op->get_req());
+  auto m = op->get_req<MTimeCheck2>();
   dout(10) << __func__ << " " << *m << dendl;
   /* handles PONG's */
   ceph_assert(m->op == MTimeCheck2::OP_PONG);
@@ -5022,7 +5022,7 @@ void Monitor::handle_timecheck_leader(MonOpRequestRef op)
 
 void Monitor::handle_timecheck_peon(MonOpRequestRef op)
 {
-  MTimeCheck2 *m = static_cast<MTimeCheck2*>(op->get_req());
+  auto m = op->get_req<MTimeCheck2>();
   dout(10) << __func__ << " " << *m << dendl;
 
   ceph_assert(is_peon());
@@ -5064,7 +5064,7 @@ void Monitor::handle_timecheck_peon(MonOpRequestRef op)
 
 void Monitor::handle_timecheck(MonOpRequestRef op)
 {
-  MTimeCheck2 *m = static_cast<MTimeCheck2*>(op->get_req());
+  auto m = op->get_req<MTimeCheck2>();
   dout(10) << __func__ << " " << *m << dendl;
 
   if (is_leader()) {
@@ -5086,7 +5086,7 @@ void Monitor::handle_timecheck(MonOpRequestRef op)
 
 void Monitor::handle_subscribe(MonOpRequestRef op)
 {
-  MMonSubscribe *m = static_cast<MMonSubscribe*>(op->get_req());
+  auto m = op->get_req<MMonSubscribe>();
   dout(10) << "handle_subscribe " << *m << dendl;
   
   bool reply = false;
@@ -5179,7 +5179,7 @@ void Monitor::handle_subscribe(MonOpRequestRef op)
 
 void Monitor::handle_get_version(MonOpRequestRef op)
 {
-  MMonGetVersion *m = static_cast<MMonGetVersion*>(op->get_req());
+  auto m = op->get_req<MMonGetVersion>();
   dout(10) << "handle_get_version " << *m << dendl;
   PaxosService *svc = NULL;
 
@@ -5269,14 +5269,14 @@ void Monitor::send_latest_monmap(Connection *con)
 
 void Monitor::handle_mon_get_map(MonOpRequestRef op)
 {
-  MMonGetMap *m = static_cast<MMonGetMap*>(op->get_req());
+  auto m = op->get_req<MMonGetMap>();
   dout(10) << "handle_mon_get_map" << dendl;
   send_latest_monmap(m->get_connection().get());
 }
 
 void Monitor::handle_mon_metadata(MonOpRequestRef op)
 {
-  MMonMetadata *m = static_cast<MMonMetadata*>(op->get_req());
+  auto m = op->get_req<MMonMetadata>();
   if (is_leader()) {
     dout(10) << __func__ << dendl;
     update_mon_metadata(m->get_source().num(), std::move(m->data));
@@ -5431,7 +5431,7 @@ int Monitor::scrub()
 
 void Monitor::handle_scrub(MonOpRequestRef op)
 {
-  MMonScrub *m = static_cast<MMonScrub*>(op->get_req());
+  auto m = op->get_req<MMonScrub>();
   dout(10) << __func__ << " " << *m << dendl;
   switch (m->op) {
   case MMonScrub::OP_SCRUB:
diff --git a/src/mon/Monitor.h b/src/mon/Monitor.h
index a369d998b7a..ae79efc7a7c 100644
--- a/src/mon/Monitor.h
+++ b/src/mon/Monitor.h
@@ -827,7 +827,7 @@ public:
       C_MonOp(_op), mon(_mm), rc(r), rs(s), rdata(rd), version(v){}
 
     void _finish(int r) override {
-      MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+      auto m = op->get_req<MMonCommand>();
       if (r >= 0) {
         ostringstream ss;
         if (!op->get_req()->get_connection()) {
diff --git a/src/mon/MonmapMonitor.cc b/src/mon/MonmapMonitor.cc
index b5b1fd3e182..ee6d077c1f5 100644
--- a/src/mon/MonmapMonitor.cc
+++ b/src/mon/MonmapMonitor.cc
@@ -216,7 +216,7 @@ void MonmapMonitor::on_active()
 
 bool MonmapMonitor::preprocess_query(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   switch (m->get_type()) {
     // READs
   case MSG_MON_COMMAND:
@@ -251,7 +251,7 @@ void MonmapMonitor::dump_info(Formatter *f)
 
 bool MonmapMonitor::preprocess_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = -1;
   bufferlist rdata;
   stringstream ss;
@@ -426,7 +426,7 @@ reply:
 
 bool MonmapMonitor::prepare_update(MonOpRequestRef op)
 {
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   dout(7) << __func__ << " " << *m << " from " << m->get_orig_source_inst() << dendl;
   
   switch (m->get_type()) {
@@ -449,7 +449,7 @@ bool MonmapMonitor::prepare_update(MonOpRequestRef op)
 
 bool MonmapMonitor::prepare_command(MonOpRequestRef op)
 {
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   stringstream ss;
   string rs;
   int err = -EINVAL;
@@ -839,7 +839,7 @@ reply:
 
 bool MonmapMonitor::preprocess_join(MonOpRequestRef op)
 {
-  MMonJoin *join = static_cast<MMonJoin*>(op->get_req());
+  auto join = op->get_req<MMonJoin>();
   dout(10) << __func__ << " " << join->name << " at " << join->addrs << dendl;
 
   MonSession *session = op->get_session();
@@ -863,7 +863,7 @@ bool MonmapMonitor::preprocess_join(MonOpRequestRef op)
 }
 bool MonmapMonitor::prepare_join(MonOpRequestRef op)
 {
-  MMonJoin *join = static_cast<MMonJoin*>(op->get_req());
+  auto join = op->get_req<MMonJoin>();
   dout(0) << "adding/updating " << join->name
 	  << " at " << join->addrs << " to monitor cluster" << dendl;
   if (pending_map.contains(join->name))
diff --git a/src/mon/OSDMonitor.cc b/src/mon/OSDMonitor.cc
index dd2661ba21d..d787e58977c 100644
--- a/src/mon/OSDMonitor.cc
+++ b/src/mon/OSDMonitor.cc
@@ -2731,7 +2731,7 @@ bool OSDMonitor::should_propose(double& delay)
 bool OSDMonitor::preprocess_get_osdmap(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MMonGetOSDMap *m = static_cast<MMonGetOSDMap*>(op->get_req());
+  auto m = op->get_req<MMonGetOSDMap>();
 
   uint64_t features = mon->get_quorum_con_features();
   if (op->get_session() && op->get_session()->con_features)
@@ -2793,7 +2793,7 @@ bool OSDMonitor::check_source(MonOpRequestRef op, uuid_d fsid) {
 bool OSDMonitor::preprocess_failure(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDFailure *m = static_cast<MOSDFailure*>(op->get_req());
+  auto m = op->get_req<MOSDFailure>();
   // who is target_osd
   int badboy = m->get_target_osd();
 
@@ -2872,7 +2872,7 @@ public:
 
   void _finish(int r) override {
     if (r == 0) {
-      MOSDMarkMeDown *m = static_cast<MOSDMarkMeDown*>(op->get_req());
+      auto m = op->get_req<MOSDMarkMeDown>();
       osdmon->mon->send_reply(
         op,
         new MOSDMarkMeDown(
@@ -2894,7 +2894,7 @@ public:
 bool OSDMonitor::preprocess_mark_me_down(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDMarkMeDown *m = static_cast<MOSDMarkMeDown*>(op->get_req());
+  auto m = op->get_req<MOSDMarkMeDown>();
   int from = m->target_osd;
 
   // check permissions
@@ -2933,7 +2933,7 @@ bool OSDMonitor::preprocess_mark_me_down(MonOpRequestRef op)
 bool OSDMonitor::prepare_mark_me_down(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDMarkMeDown *m = static_cast<MOSDMarkMeDown*>(op->get_req());
+  auto m = op->get_req<MOSDMarkMeDown>();
   int target_osd = m->target_osd;
 
   ceph_assert(osdmap.is_up(target_osd));
@@ -2949,7 +2949,7 @@ bool OSDMonitor::prepare_mark_me_down(MonOpRequestRef op)
 bool OSDMonitor::preprocess_mark_me_dead(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDMarkMeDead *m = static_cast<MOSDMarkMeDead*>(op->get_req());
+  auto m = op->get_req<MOSDMarkMeDead>();
   int from = m->target_osd;
 
   // check permissions
@@ -2979,7 +2979,7 @@ bool OSDMonitor::preprocess_mark_me_dead(MonOpRequestRef op)
 bool OSDMonitor::prepare_mark_me_dead(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDMarkMeDead *m = static_cast<MOSDMarkMeDead*>(op->get_req());
+  auto m = op->get_req<MOSDMarkMeDead>();
   int target_osd = m->target_osd;
 
   ceph_assert(osdmap.is_down(target_osd));
@@ -3208,7 +3208,7 @@ void OSDMonitor::force_failure(int target_osd, int by)
 bool OSDMonitor::prepare_failure(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDFailure *m = static_cast<MOSDFailure*>(op->get_req());
+  auto m = op->get_req<MOSDFailure>();
   dout(1) << "prepare_failure osd." << m->get_target_osd()
 	  << " " << m->get_target_addrs()
 	  << " from " << m->get_orig_source()
@@ -3316,7 +3316,7 @@ void OSDMonitor::take_all_failures(list<MonOpRequestRef>& ls)
 bool OSDMonitor::preprocess_boot(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDBoot *m = static_cast<MOSDBoot*>(op->get_req());
+  auto m = op->get_req<MOSDBoot>();
   int from = m->get_orig_source_inst().name.num();
 
   // check permissions, ignore if failed (no response expected)
@@ -3439,7 +3439,7 @@ bool OSDMonitor::preprocess_boot(MonOpRequestRef op)
 bool OSDMonitor::prepare_boot(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDBoot *m = static_cast<MOSDBoot*>(op->get_req());
+  auto m = op->get_req<MOSDBoot>();
   dout(7) << __func__ << " from " << m->get_source()
 	  << " sb " << m->sb
 	  << " client_addrs" << m->get_connection()->get_peer_addrs()
@@ -3594,7 +3594,7 @@ bool OSDMonitor::prepare_boot(MonOpRequestRef op)
 void OSDMonitor::_booted(MonOpRequestRef op, bool logit)
 {
   op->mark_osdmon_event(__func__);
-  MOSDBoot *m = static_cast<MOSDBoot*>(op->get_req());
+  auto m = op->get_req<MOSDBoot>();
   dout(7) << "_booted " << m->get_orig_source_inst() 
 	  << " w " << m->sb.weight << " from " << m->sb.current_epoch << dendl;
 
@@ -3613,7 +3613,7 @@ void OSDMonitor::_booted(MonOpRequestRef op, bool logit)
 bool OSDMonitor::preprocess_full(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDFull *m = static_cast<MOSDFull*>(op->get_req());
+  auto m = op->get_req<MOSDFull>();
   int from = m->get_orig_source().num();
   set<string> state;
   unsigned mask = CEPH_OSD_NEARFULL | CEPH_OSD_BACKFILLFULL | CEPH_OSD_FULL;
@@ -3664,7 +3664,7 @@ bool OSDMonitor::preprocess_full(MonOpRequestRef op)
 bool OSDMonitor::prepare_full(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  const MOSDFull *m = static_cast<MOSDFull*>(op->get_req());
+  auto m = op->get_req<MOSDFull>();
   const int from = m->get_orig_source().num();
 
   const unsigned mask = CEPH_OSD_NEARFULL | CEPH_OSD_BACKFILLFULL | CEPH_OSD_FULL;
@@ -3705,7 +3705,7 @@ bool OSDMonitor::prepare_full(MonOpRequestRef op)
 bool OSDMonitor::preprocess_alive(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDAlive *m = static_cast<MOSDAlive*>(op->get_req());
+  auto m = op->get_req<MOSDAlive>();
   int from = m->get_orig_source().num();
 
   // check permissions, ignore if failed
@@ -3744,7 +3744,7 @@ bool OSDMonitor::preprocess_alive(MonOpRequestRef op)
 bool OSDMonitor::prepare_alive(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDAlive *m = static_cast<MOSDAlive*>(op->get_req());
+  auto m = op->get_req<MOSDAlive>();
   int from = m->get_orig_source().num();
 
   if (0) {  // we probably don't care much about these
@@ -3772,7 +3772,7 @@ void OSDMonitor::_reply_map(MonOpRequestRef op, epoch_t e)
 bool OSDMonitor::preprocess_pg_created(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  auto m = static_cast<MOSDPGCreated*>(op->get_req());
+  auto m  = op->get_req<MOSDPGCreated>();
   dout(10) << __func__ << " " << *m << dendl;
   auto session = op->get_session();
   mon->no_reply(op);
@@ -3792,7 +3792,7 @@ bool OSDMonitor::preprocess_pg_created(MonOpRequestRef op)
 bool OSDMonitor::prepare_pg_created(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  auto m = static_cast<MOSDPGCreated*>(op->get_req());
+  auto m = op->get_req<MOSDPGCreated>();
   dout(10) << __func__ << " " << *m << dendl;
   auto src = m->get_orig_source();
   auto from = src.num();
@@ -3810,7 +3810,7 @@ bool OSDMonitor::prepare_pg_created(MonOpRequestRef op)
 bool OSDMonitor::preprocess_pg_ready_to_merge(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  auto m = static_cast<MOSDPGReadyToMerge*>(op->get_req());
+  auto m = op->get_req<MOSDPGReadyToMerge>();
   dout(10) << __func__ << " " << *m << dendl;
   const pg_pool_t *pi;
   auto session = op->get_session();
@@ -3850,7 +3850,7 @@ bool OSDMonitor::preprocess_pg_ready_to_merge(MonOpRequestRef op)
 bool OSDMonitor::prepare_pg_ready_to_merge(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  auto m = static_cast<MOSDPGReadyToMerge*>(op->get_req());
+  auto m  = op->get_req<MOSDPGReadyToMerge>();
   dout(10) << __func__ << " " << *m << dendl;
   pg_pool_t p;
   if (pending_inc.new_pools.count(m->pgid.pool()))
@@ -3911,7 +3911,7 @@ bool OSDMonitor::prepare_pg_ready_to_merge(MonOpRequestRef op)
 
 bool OSDMonitor::preprocess_pgtemp(MonOpRequestRef op)
 {
-  MOSDPGTemp *m = static_cast<MOSDPGTemp*>(op->get_req());
+  auto m = op->get_req<MOSDPGTemp>();
   dout(10) << "preprocess_pgtemp " << *m << dendl;
   mempool::osdmap::vector<int> empty;
   int from = m->get_orig_source().num();
@@ -4018,7 +4018,7 @@ void OSDMonitor::update_up_thru(int from, epoch_t up_thru)
 bool OSDMonitor::prepare_pgtemp(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MOSDPGTemp *m = static_cast<MOSDPGTemp*>(op->get_req());
+  auto m = op->get_req<MOSDPGTemp>();
   int from = m->get_orig_source().num();
   dout(7) << "prepare_pgtemp e" << m->map_epoch << " from " << m->get_orig_source_inst() << dendl;
   for (map<pg_t,vector<int32_t> >::iterator p = m->pg_temp.begin(); p != m->pg_temp.end(); ++p) {
@@ -4057,7 +4057,7 @@ bool OSDMonitor::prepare_pgtemp(MonOpRequestRef op)
 bool OSDMonitor::preprocess_remove_snaps(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MRemoveSnaps *m = static_cast<MRemoveSnaps*>(op->get_req());
+  auto m = op->get_req<MRemoveSnaps>();
   dout(7) << "preprocess_remove_snaps " << *m << dendl;
 
   // check privilege, ignore if failed
@@ -4108,7 +4108,7 @@ bool OSDMonitor::preprocess_remove_snaps(MonOpRequestRef op)
 bool OSDMonitor::prepare_remove_snaps(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MRemoveSnaps *m = static_cast<MRemoveSnaps*>(op->get_req());
+  auto m = op->get_req<MRemoveSnaps>();
   dout(7) << "prepare_remove_snaps " << *m << dendl;
 
   for (auto& [pool, snaps] : m->snaps) {
@@ -4157,7 +4157,7 @@ bool OSDMonitor::prepare_remove_snaps(MonOpRequestRef op)
 bool OSDMonitor::preprocess_get_purged_snaps(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  const MMonGetPurgedSnaps *m = static_cast<MMonGetPurgedSnaps*>(op->get_req());
+  auto m = op->get_req<MMonGetPurgedSnaps>();
   dout(7) << __func__ << " " << *m << dendl;
 
   map<epoch_t,mempool::osdmap::map<int64_t,snap_interval_set_t>> r;
@@ -4229,7 +4229,7 @@ bool OSDMonitor::preprocess_beacon(MonOpRequestRef op)
 bool OSDMonitor::prepare_beacon(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  const auto beacon = static_cast<MOSDBeacon*>(op->get_req());
+  const auto beacon = op->get_req<MOSDBeacon>();
   const auto src = beacon->get_orig_source();
   dout(10) << __func__ << " " << *beacon
 	   << " from " << src << dendl;
@@ -5238,7 +5238,7 @@ namespace {
 bool OSDMonitor::preprocess_command(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   int r = 0;
   bufferlist rdata;
   stringstream ss, ds;
@@ -7106,7 +7106,7 @@ bool OSDMonitor::update_pools_status()
 int OSDMonitor::prepare_new_pool(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   dout(10) << "prepare_new_pool from " << m->get_connection() << dendl;
   MonSession *session = op->get_session();
   if (!session)
@@ -9206,7 +9206,7 @@ int OSDMonitor::prepare_command_osd_new(
 bool OSDMonitor::prepare_command(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   stringstream ss;
   cmdmap_t cmdmap;
   if (!cmdmap_from_json(m->cmd, &cmdmap, ss)) {
@@ -9406,7 +9406,7 @@ bool OSDMonitor::prepare_command_impl(MonOpRequestRef op,
 				      const cmdmap_t& cmdmap)
 {
   op->mark_osdmon_event(__func__);
-  MMonCommand *m = static_cast<MMonCommand*>(op->get_req());
+  auto m = op->get_req<MMonCommand>();
   bool ret = false;
   stringstream ss;
   string rs;
@@ -13251,7 +13251,7 @@ bool OSDMonitor::enforce_pool_op_caps(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
 
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   MonSession *session = op->get_session();
   if (!session) {
     _pool_op_reply(op, -EPERM, osdmap.get_epoch());
@@ -13297,7 +13297,7 @@ bool OSDMonitor::enforce_pool_op_caps(MonOpRequestRef op)
 bool OSDMonitor::preprocess_pool_op(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
 
   if (enforce_pool_op_caps(op)) {
     return true;
@@ -13422,7 +13422,7 @@ bool OSDMonitor::_is_pending_removed_snap(int64_t pool, snapid_t snap)
 bool OSDMonitor::preprocess_pool_op_create(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   int64_t pool = osdmap.lookup_pg_pool_name(m->name.c_str());
   if (pool >= 0) {
     _pool_op_reply(op, 0, osdmap.get_epoch());
@@ -13435,7 +13435,7 @@ bool OSDMonitor::preprocess_pool_op_create(MonOpRequestRef op)
 bool OSDMonitor::prepare_pool_op(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   dout(10) << "prepare_pool_op " << *m << dendl;
   if (m->op == POOL_OP_CREATE) {
     return prepare_pool_op_create(op);
@@ -13874,7 +13874,7 @@ int OSDMonitor::_prepare_rename_pool(int64_t pool, string newname)
 bool OSDMonitor::prepare_pool_op_delete(MonOpRequestRef op)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   ostringstream ss;
   int ret = _prepare_remove_pool(m->pool, &ss, false);
   if (ret == -EAGAIN) {
@@ -13892,7 +13892,7 @@ void OSDMonitor::_pool_op_reply(MonOpRequestRef op,
                                 int ret, epoch_t epoch, bufferlist *blp)
 {
   op->mark_osdmon_event(__func__);
-  MPoolOp *m = static_cast<MPoolOp*>(op->get_req());
+  auto m = op->get_req<MPoolOp>();
   dout(20) << "_pool_op_reply " << ret << dendl;
   MPoolOpReply *reply = new MPoolOpReply(m->fsid, m->get_tid(),
 					 ret, epoch, get_last_committed(), blp);
diff --git a/src/mon/Paxos.cc b/src/mon/Paxos.cc
index 01a519ce77c..2859ff2ce47 100644
--- a/src/mon/Paxos.cc
+++ b/src/mon/Paxos.cc
@@ -217,7 +217,7 @@ void Paxos::handle_collect(MonOpRequestRef op)
   
   op->mark_paxos_event("handle_collect");
 
-  MMonPaxos *collect = static_cast<MMonPaxos*>(op->get_req());
+  auto collect = op->get_req<MMonPaxos>();
   dout(10) << "handle_collect " << *collect << dendl;
 
   ceph_assert(mon->is_peon()); // mon epoch filter should catch strays
@@ -461,7 +461,7 @@ void Paxos::_sanity_check_store()
 void Paxos::handle_last(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_last");
-  MMonPaxos *last = static_cast<MMonPaxos*>(op->get_req());
+  auto last = op->get_req<MMonPaxos>();
   bool need_refresh = false;
   int from = last->get_source().num();
 
@@ -705,7 +705,7 @@ void Paxos::begin(bufferlist& v)
 void Paxos::handle_begin(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_begin");
-  MMonPaxos *begin = static_cast<MMonPaxos*>(op->get_req());
+  auto begin = op->get_req<MMonPaxos>();
   dout(10) << "handle_begin " << *begin << dendl;
 
   // can we accept this?
@@ -765,7 +765,7 @@ void Paxos::handle_begin(MonOpRequestRef op)
 void Paxos::handle_accept(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_accept");
-  MMonPaxos *accept = static_cast<MMonPaxos*>(op->get_req());
+  auto accept = op->get_req<MMonPaxos>();
   dout(10) << "handle_accept " << *accept << dendl;
   int from = accept->get_source().num();
 
@@ -947,7 +947,7 @@ void Paxos::commit_finish()
 void Paxos::handle_commit(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_commit");
-  MMonPaxos *commit = static_cast<MMonPaxos*>(op->get_req());
+  auto commit = op->get_req<MMonPaxos>();
   dout(10) << "handle_commit on " << commit->last_committed << dendl;
 
   logger->inc(l_paxos_commit);
@@ -1095,7 +1095,7 @@ void Paxos::finish_round()
 void Paxos::handle_lease(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_lease");
-  MMonPaxos *lease = static_cast<MMonPaxos*>(op->get_req());
+  auto lease = op->get_req<MMonPaxos>();
   // sanity
   if (!mon->is_peon() ||
       last_committed != lease->last_committed) {
@@ -1145,7 +1145,7 @@ void Paxos::handle_lease(MonOpRequestRef op)
 void Paxos::handle_lease_ack(MonOpRequestRef op)
 {
   op->mark_paxos_event("handle_lease_ack");
-  MMonPaxos *ack = static_cast<MMonPaxos*>(op->get_req());
+  auto ack = op->get_req<MMonPaxos>();
   int from = ack->get_source().num();
 
   if (!lease_ack_timeout_event) {
diff --git a/src/mon/PaxosService.cc b/src/mon/PaxosService.cc
index 06776635f94..c71d026ffba 100644
--- a/src/mon/PaxosService.cc
+++ b/src/mon/PaxosService.cc
@@ -32,7 +32,7 @@ static ostream& _prefix(std::ostream *_dout, Monitor *mon, Paxos *paxos, string
 bool PaxosService::dispatch(MonOpRequestRef op)
 {
   ceph_assert(op->is_type_service() || op->is_type_command());
-  PaxosServiceMessage *m = static_cast<PaxosServiceMessage*>(op->get_req());
+  auto m = op->get_req<PaxosServiceMessage>();
   op->mark_event("psvc:dispatch");
 
   dout(10) << __func__ << " " << m << " " << *m