SERVER-20224 commands that write support writeConcern

60 files changed, 450 insertions, 126 deletions

diff --git a/src/mongo/db/commands/apply_ops_cmd.cpp b/src/mongo/db/commands/apply_ops_cmd.cpp
index 2301916ef6c..12df18040a9 100644
--- a/src/mongo/db/commands/apply_ops_cmd.cpp
+++ b/src/mongo/db/commands/apply_ops_cmd.cpp
@@ -53,7 +53,6 @@
 #include "mongo/db/repl/oplog.h"
 #include "mongo/db/repl/repl_client_info.h"
 #include "mongo/db/repl/replication_coordinator_global.h"
-#include "mongo/db/write_concern.h"
 #include "mongo/util/log.h"
 #include "mongo/util/scopeguard.h"
 
@@ -72,6 +71,10 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
+
     virtual void help(stringstream& help) const {
         help << "internal (sharding)\n{ applyOps : [ ] , preCondition : [ { ns : ... , q : ... , "
                 "res : ... } ] }";
@@ -112,14 +115,6 @@ public:
             }
         }
 
-        StatusWith<WriteConcernOptions> wcResult = extractWriteConcern(txn, cmdObj, dbname);
-        if (!wcResult.isOK()) {
-            return appendCommandStatus(result, wcResult.getStatus());
-        }
-        txn->setWriteConcern(wcResult.getValue());
-        setupSynchronousCommit(txn);
-
-
         auto client = txn->getClient();
         auto lastOpAtOperationStart = repl::ReplClientInfo::forClient(client).getLastOp();
         ScopeGuard lastOpSetterGuard =
@@ -136,14 +131,6 @@ public:
             lastOpSetterGuard.Dismiss();
         }
 
-        WriteConcernResult res;
-        auto waitForWCStatus =
-            waitForWriteConcern(txn,
-                                repl::ReplClientInfo::forClient(txn->getClient()).getLastOp(),
-                                txn->getWriteConcern(),
-                                &res);
-        appendCommandWCStatus(result, waitForWCStatus);
-
         return applyOpsStatus;
     }
 
diff --git a/src/mongo/db/commands/authentication_commands.cpp b/src/mongo/db/commands/authentication_commands.cpp
index b30a7694417..6fc6268a807 100644
--- a/src/mongo/db/commands/authentication_commands.cpp
+++ b/src/mongo/db/commands/authentication_commands.cpp
@@ -105,6 +105,9 @@ public:
     void help(stringstream& h) const {
         h << "internal";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
@@ -360,6 +363,9 @@ public:
     void help(stringstream& h) const {
         h << "de-authenticate";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     CmdLogout() : Command("logout") {}
     bool run(OperationContext* txn,
              const string& dbname,
diff --git a/src/mongo/db/commands/authentication_commands.h b/src/mongo/db/commands/authentication_commands.h
index d11ae5bc536..4b1caf54913 100644
--- a/src/mongo/db/commands/authentication_commands.h
+++ b/src/mongo/db/commands/authentication_commands.h
@@ -46,6 +46,9 @@ public:
     virtual void help(std::stringstream& ss) const {
         ss << "internal";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
diff --git a/src/mongo/db/commands/clone.cpp b/src/mongo/db/commands/clone.cpp
index 499b8827a76..9ce858feb3d 100644
--- a/src/mongo/db/commands/clone.cpp
+++ b/src/mongo/db/commands/clone.cpp
@@ -60,6 +60,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
+
     virtual void help(stringstream& help) const {
         help << "clone this database from an instance of the db on another host\n";
         help << "{clone: \"host13\"[, slaveOk: <bool>]}";
diff --git a/src/mongo/db/commands/clone_collection.cpp b/src/mongo/db/commands/clone_collection.cpp
index efd3500d395..85bd9c6b1ab 100644
--- a/src/mongo/db/commands/clone_collection.cpp
+++ b/src/mongo/db/commands/clone_collection.cpp
@@ -71,6 +71,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
+
     virtual std::string parseNs(const std::string& dbname, const BSONObj& cmdObj) const {
         return parseNsFullyQualified(dbname, cmdObj);
     }
diff --git a/src/mongo/db/commands/collection_to_capped.cpp b/src/mongo/db/commands/collection_to_capped.cpp
index a0b283ebc49..03d8552e2ae 100644
--- a/src/mongo/db/commands/collection_to_capped.cpp
+++ b/src/mongo/db/commands/collection_to_capped.cpp
@@ -56,6 +56,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void help(stringstream& help) const {
         help << "{ cloneCollectionAsCapped:<fromName>, toCollection:<toName>, size:<sizeInBytes> }";
     }
@@ -129,6 +132,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void help(stringstream& help) const {
         help << "{ convertToCapped:<fromCollectionName>, size:<sizeInBytes> }";
     }
diff --git a/src/mongo/db/commands/compact.cpp b/src/mongo/db/commands/compact.cpp
index cff4a4c359b..a87f2167be6 100644
--- a/src/mongo/db/commands/compact.cpp
+++ b/src/mongo/db/commands/compact.cpp
@@ -56,6 +56,9 @@ using std::stringstream;
 
 class CompactCmd : public Command {
 public:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return false;
     }
diff --git a/src/mongo/db/commands/conn_pool_stats.cpp b/src/mongo/db/commands/conn_pool_stats.cpp
index ffd0945ed3f..2a3b2881d45 100644
--- a/src/mongo/db/commands/conn_pool_stats.cpp
+++ b/src/mongo/db/commands/conn_pool_stats.cpp
@@ -53,6 +53,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     void addRequiredPrivileges(const std::string& dbname,
                                const BSONObj& cmdObj,
                                std::vector<Privilege>* out) override {
diff --git a/src/mongo/db/commands/conn_pool_sync.cpp b/src/mongo/db/commands/conn_pool_sync.cpp
index 839e3a045b4..cb9410d7619 100644
--- a/src/mongo/db/commands/conn_pool_sync.cpp
+++ b/src/mongo/db/commands/conn_pool_sync.cpp
@@ -43,6 +43,9 @@ public:
     virtual void help(std::stringstream& help) const {
         help << "internal";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
diff --git a/src/mongo/db/commands/connection_status.cpp b/src/mongo/db/commands/connection_status.cpp
index 340bc032cdb..8cf1a94ebd6 100644
--- a/src/mongo/db/commands/connection_status.cpp
+++ b/src/mongo/db/commands/connection_status.cpp
@@ -44,6 +44,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
diff --git a/src/mongo/db/commands/copydb.cpp b/src/mongo/db/commands/copydb.cpp
index a0ad9c46d81..7619c87a20d 100644
--- a/src/mongo/db/commands/copydb.cpp
+++ b/src/mongo/db/commands/copydb.cpp
@@ -98,6 +98,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual Status checkAuthForCommand(ClientBasic* client,
                                        const std::string& dbname,
diff --git a/src/mongo/db/commands/copydb_start_commands.cpp b/src/mongo/db/commands/copydb_start_commands.cpp
index feb96a9552a..e37695e4181 100644
--- a/src/mongo/db/commands/copydb_start_commands.cpp
+++ b/src/mongo/db/commands/copydb_start_commands.cpp
@@ -80,6 +80,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
@@ -149,6 +153,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual Status checkAuthForCommand(ClientBasic* client,
                                        const std::string& dbname,
                                        const BSONObj& cmdObj) {
diff --git a/src/mongo/db/commands/count_cmd.cpp b/src/mongo/db/commands/count_cmd.cpp
index c292f27c40c..b8367c35642 100644
--- a/src/mongo/db/commands/count_cmd.cpp
+++ b/src/mongo/db/commands/count_cmd.cpp
@@ -55,6 +55,9 @@ using std::stringstream;
 class CmdCount : public Command {
 public:
     CmdCount() : Command("count") {}
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         // ok on --slave setups
         return repl::getGlobalReplicationCoordinator()->getSettings().isSlave();
diff --git a/src/mongo/db/commands/cpuprofile.cpp b/src/mongo/db/commands/cpuprofile.cpp
index 2706d44510b..24fbd034b81 100644
--- a/src/mongo/db/commands/cpuprofile.cpp
+++ b/src/mongo/db/commands/cpuprofile.cpp
@@ -91,6 +91,9 @@ public:
     // This is an abuse of the global dbmutex.  We only really need to
     // ensure that only one cpuprofiler command runs at once; it would
     // be fine for it to run concurrently with other operations.
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 };
 
 /**
diff --git a/src/mongo/db/commands/create_indexes.cpp b/src/mongo/db/commands/create_indexes.cpp
index cb1f09988d2..d99c74fc1ae 100644
--- a/src/mongo/db/commands/create_indexes.cpp
+++ b/src/mongo/db/commands/create_indexes.cpp
@@ -62,6 +62,9 @@ class CmdCreateIndex : public Command {
 public:
     CmdCreateIndex() : Command("createIndexes") {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual bool slaveOk() const {
         return false;
     }  // TODO: this could be made true...
diff --git a/src/mongo/db/commands/current_op.cpp b/src/mongo/db/commands/current_op.cpp
index 680a99ced73..fed56b550ad 100644
--- a/src/mongo/db/commands/current_op.cpp
+++ b/src/mongo/db/commands/current_op.cpp
@@ -54,6 +54,10 @@ public:
     CurrentOpCommand() : Command("currentOp") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const final {
         return true;
     }
diff --git a/src/mongo/db/commands/dbhash.cpp b/src/mongo/db/commands/dbhash.cpp
index dcb63a5936c..2bc75db0b74 100644
--- a/src/mongo/db/commands/dbhash.cpp
+++ b/src/mongo/db/commands/dbhash.cpp
@@ -64,6 +64,10 @@ class DBHashCmd : public Command {
 public:
     DBHashCmd() : Command("dbHash", false, "dbhash") {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/distinct.cpp b/src/mongo/db/commands/distinct.cpp
index c03f6382fe0..966a7d5b32b 100644
--- a/src/mongo/db/commands/distinct.cpp
+++ b/src/mongo/db/commands/distinct.cpp
@@ -75,6 +75,9 @@ public:
     virtual bool slaveOverrideOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     bool supportsReadConcern() const final {
         return true;
     }
diff --git a/src/mongo/db/commands/drop_indexes.cpp b/src/mongo/db/commands/drop_indexes.cpp
index cead3ea45c7..950cf437750 100644
--- a/src/mongo/db/commands/drop_indexes.cpp
+++ b/src/mongo/db/commands/drop_indexes.cpp
@@ -70,6 +70,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void help(stringstream& help) const {
         help << "drop indexes for a collection";
     }
@@ -99,6 +102,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }  // can reindex on a secondary
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void help(stringstream& help) const {
         help << "re-index a collection";
     }
diff --git a/src/mongo/db/commands/explain_cmd.cpp b/src/mongo/db/commands/explain_cmd.cpp
index dc467846603..b0c8f1baec3 100644
--- a/src/mongo/db/commands/explain_cmd.cpp
+++ b/src/mongo/db/commands/explain_cmd.cpp
@@ -57,6 +57,10 @@ public:
     CmdExplain() : Command("explain") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     /**
      * Running an explain on a secondary requires explicitly setting slaveOk.
      */
diff --git a/src/mongo/db/commands/fail_point_cmd.cpp b/src/mongo/db/commands/fail_point_cmd.cpp
index 65ca22d59e0..22de01b1d2c 100644
--- a/src/mongo/db/commands/fail_point_cmd.cpp
+++ b/src/mongo/db/commands/fail_point_cmd.cpp
@@ -70,6 +70,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual bool adminOnly() const {
         return true;
     }
diff --git a/src/mongo/db/commands/find_and_modify.cpp b/src/mongo/db/commands/find_and_modify.cpp
index 32b48d4eb3e..c806e67bdb7 100644
--- a/src/mongo/db/commands/find_and_modify.cpp
+++ b/src/mongo/db/commands/find_and_modify.cpp
@@ -63,6 +63,7 @@
 #include "mongo/db/repl/replication_coordinator_global.h"
 #include "mongo/db/s/collection_sharding_state.h"
 #include "mongo/db/write_concern.h"
+#include "mongo/s/d_state.h"
 #include "mongo/util/log.h"
 #include "mongo/util/scopeguard.h"
 
@@ -214,6 +215,9 @@ public:
     bool slaveOk() const override {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     void addRequiredPrivileges(const std::string& dbname,
                                const BSONObj& cmdObj,
                                std::vector<Privilege>* out) override {
@@ -332,13 +336,6 @@ public:
         const FindAndModifyRequest& args = parseStatus.getValue();
         const NamespaceString& nsString = args.getNamespaceString();
 
-        StatusWith<WriteConcernOptions> wcResult = extractWriteConcern(txn, cmdObj, dbName);
-        if (!wcResult.isOK()) {
-            return appendCommandStatus(result, wcResult.getStatus());
-        }
-        txn->setWriteConcern(wcResult.getValue());
-        setupSynchronousCommit(txn);
-
         boost::optional<DisableDocumentValidation> maybeDisableValidation;
         if (shouldBypassDocumentValidationForCommand(cmdObj))
             maybeDisableValidation.emplace(txn);
@@ -350,6 +347,11 @@ public:
                          &repl::ReplClientInfo::setLastOpToSystemLastOpTime,
                          txn);
 
+        // If this is the local database, don't set last op.
+        if (dbName == "local") {
+            lastOpSetterGuard.Dismiss();
+        }
+
         // Although usually the PlanExecutor handles WCE internally, it will throw WCEs when it is
         // executing a findAndModify. This is done to ensure that we can always match, modify, and
         // return the document under concurrency, if a matching document exists.
@@ -507,14 +509,6 @@ public:
             lastOpSetterGuard.Dismiss();
         }
 
-        WriteConcernResult res;
-        auto waitForWCStatus =
-            waitForWriteConcern(txn,
-                                repl::ReplClientInfo::forClient(txn->getClient()).getLastOp(),
-                                txn->getWriteConcern(),
-                                &res);
-        appendCommandWCStatus(result, waitForWCStatus);
-
         return true;
     }
 
diff --git a/src/mongo/db/commands/find_cmd.cpp b/src/mongo/db/commands/find_cmd.cpp
index 82c63c01cf8..f3a9ea67897 100644
--- a/src/mongo/db/commands/find_cmd.cpp
+++ b/src/mongo/db/commands/find_cmd.cpp
@@ -72,6 +72,10 @@ public:
     FindCmd() : Command("find") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const override {
         return false;
     }
diff --git a/src/mongo/db/commands/fsync.cpp b/src/mongo/db/commands/fsync.cpp
index 8bc028c926f..d8545f0853d 100644
--- a/src/mongo/db/commands/fsync.cpp
+++ b/src/mongo/db/commands/fsync.cpp
@@ -103,6 +103,9 @@ public:
         locked = false;
         pendingUnlock = false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
@@ -185,6 +188,10 @@ public:
     FSyncUnlockCommand() : Command("fsyncUnlock") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const override {
         return true;
     }
diff --git a/src/mongo/db/commands/generic.cpp b/src/mongo/db/commands/generic.cpp
index 9795e7f2b3e..05724e33705 100644
--- a/src/mongo/db/commands/generic.cpp
+++ b/src/mongo/db/commands/generic.cpp
@@ -78,6 +78,9 @@ public:
     virtual bool adminOnly() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
@@ -110,6 +113,9 @@ public:
         help << "a way to check that the server is alive. responds immediately even if server is "
                 "in a db lock.";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
@@ -133,6 +139,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
@@ -165,6 +174,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual void help(stringstream& help) const {
         help << "returns information about the daemon's host";
     }
@@ -207,6 +220,9 @@ public:
 class LogRotateCmd : public Command {
 public:
     LogRotateCmd() : Command("logRotate") {}
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
@@ -240,6 +256,9 @@ public:
         help << "get a list of all db commands";
     }
     ListCommandsCmd() : Command("listCommands", false) {}
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
@@ -341,6 +360,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
@@ -363,6 +385,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return true;
     }
@@ -430,6 +455,9 @@ public:
     void help(stringstream& h) const {
         h << "get argv";
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return true;
     }
diff --git a/src/mongo/db/commands/geo_near_cmd.cpp b/src/mongo/db/commands/geo_near_cmd.cpp
index 743329370be..080903e2320 100644
--- a/src/mongo/db/commands/geo_near_cmd.cpp
+++ b/src/mongo/db/commands/geo_near_cmd.cpp
@@ -63,6 +63,9 @@ class Geo2dFindNearCmd : public Command {
 public:
     Geo2dFindNearCmd() : Command("geoNear") {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/get_last_error.cpp b/src/mongo/db/commands/get_last_error.cpp
index 4b026165cb0..98fbdcb9049 100644
--- a/src/mongo/db/commands/get_last_error.cpp
+++ b/src/mongo/db/commands/get_last_error.cpp
@@ -56,6 +56,9 @@ using std::stringstream;
 */
 class CmdResetError : public Command {
 public:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
@@ -80,6 +83,9 @@ public:
 class CmdGetLastError : public Command {
 public:
     CmdGetLastError() : Command("getLastError", false, "getlasterror") {}
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
@@ -283,6 +289,9 @@ public:
 
 class CmdGetPrevError : public Command {
 public:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void help(stringstream& help) const {
         help << "check for errors since last reseterror commandcal";
     }
diff --git a/src/mongo/db/commands/getmore_cmd.cpp b/src/mongo/db/commands/getmore_cmd.cpp
index 0d474ed100d..9b7e54b04ca 100644
--- a/src/mongo/db/commands/getmore_cmd.cpp
+++ b/src/mongo/db/commands/getmore_cmd.cpp
@@ -80,6 +80,10 @@ public:
     GetMoreCmd() : Command("getMore") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const override {
         return true;
     }
diff --git a/src/mongo/db/commands/group_cmd.cpp b/src/mongo/db/commands/group_cmd.cpp
index e49a9081b49..25554261b69 100644
--- a/src/mongo/db/commands/group_cmd.cpp
+++ b/src/mongo/db/commands/group_cmd.cpp
@@ -52,6 +52,10 @@ public:
     GroupCommand() : Command("group") {}
 
 private:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual bool maintenanceOk() const {
         return false;
     }
diff --git a/src/mongo/db/commands/hashcmd.cpp b/src/mongo/db/commands/hashcmd.cpp
index f65690dddb3..76c1960f804 100644
--- a/src/mongo/db/commands/hashcmd.cpp
+++ b/src/mongo/db/commands/hashcmd.cpp
@@ -53,6 +53,9 @@ using std::stringstream;
 class CmdHashElt : public Command {
 public:
     CmdHashElt() : Command("_hashBSONElement"){};
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/index_filter_commands.cpp b/src/mongo/db/commands/index_filter_commands.cpp
index 936dab77670..287e7e5950f 100644
--- a/src/mongo/db/commands/index_filter_commands.cpp
+++ b/src/mongo/db/commands/index_filter_commands.cpp
@@ -145,6 +145,10 @@ bool IndexFilterCommand::run(OperationContext* txn,
 }
 
 
+bool IndexFilterCommand::supportsWriteConcern(const BSONObj& cmd) const {
+    return false;
+}
+
 bool IndexFilterCommand::slaveOk() const {
     return false;
 }
diff --git a/src/mongo/db/commands/index_filter_commands.h b/src/mongo/db/commands/index_filter_commands.h
index ddd2553823a..7ba1157bef7 100644
--- a/src/mongo/db/commands/index_filter_commands.h
+++ b/src/mongo/db/commands/index_filter_commands.h
@@ -70,6 +70,8 @@ public:
              std::string& errmsg,
              BSONObjBuilder& result);
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override;
+
     virtual bool slaveOk() const;
 
     virtual bool slaveOverrideOk() const;
diff --git a/src/mongo/db/commands/isself.cpp b/src/mongo/db/commands/isself.cpp
index a3d8a3af918..0db7ba01440 100644
--- a/src/mongo/db/commands/isself.cpp
+++ b/src/mongo/db/commands/isself.cpp
@@ -45,6 +45,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void help(stringstream& help) const {
         help << "{ _isSelf : 1 } INTERNAL ONLY";
     }
diff --git a/src/mongo/db/commands/kill_op.cpp b/src/mongo/db/commands/kill_op.cpp
index 753d48b9362..57838d625d1 100644
--- a/src/mongo/db/commands/kill_op.cpp
+++ b/src/mongo/db/commands/kill_op.cpp
@@ -50,6 +50,10 @@ public:
     KillOpCommand() : Command("killOp") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const final {
         return true;
     }
diff --git a/src/mongo/db/commands/killcursors_common.h b/src/mongo/db/commands/killcursors_common.h
index 7d082063858..db92c7ab21b 100644
--- a/src/mongo/db/commands/killcursors_common.h
+++ b/src/mongo/db/commands/killcursors_common.h
@@ -42,6 +42,10 @@ public:
     KillCursorsCmdBase() : Command("killCursors") {}
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     bool slaveOk() const final {
         return true;
     }
diff --git a/src/mongo/db/commands/list_collections.cpp b/src/mongo/db/commands/list_collections.cpp
index abd8302434f..0f9876420de 100644
--- a/src/mongo/db/commands/list_collections.cpp
+++ b/src/mongo/db/commands/list_collections.cpp
@@ -149,6 +149,9 @@ public:
     virtual bool adminOnly() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     virtual void help(stringstream& help) const {
         help << "list collections for this db";
diff --git a/src/mongo/db/commands/list_databases.cpp b/src/mongo/db/commands/list_databases.cpp
index f7184d7de7d..88978246b19 100644
--- a/src/mongo/db/commands/list_databases.cpp
+++ b/src/mongo/db/commands/list_databases.cpp
@@ -57,6 +57,9 @@ public:
     virtual bool adminOnly() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void help(stringstream& help) const {
         help << "list databases on this server";
     }
diff --git a/src/mongo/db/commands/list_indexes.cpp b/src/mongo/db/commands/list_indexes.cpp
index 5d443e98e4b..f6d144de358 100644
--- a/src/mongo/db/commands/list_indexes.cpp
+++ b/src/mongo/db/commands/list_indexes.cpp
@@ -82,6 +82,9 @@ public:
     virtual bool adminOnly() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     virtual void help(stringstream& help) const {
         help << "list indexes for a collection";
diff --git a/src/mongo/db/commands/mr.cpp b/src/mongo/db/commands/mr.cpp
index 56aedcd16ae..9e5e6259d3e 100644
--- a/src/mongo/db/commands/mr.cpp
+++ b/src/mongo/db/commands/mr.cpp
@@ -602,7 +602,7 @@ long long State::postProcessCollectionNonAtomic(OperationContext* txn,
         ScopedTransaction transaction(txn, MODE_X);
         Lock::GlobalWrite lock(txn->lockState());  // TODO(erh): why global???
         // replace: just rename from temp to final collection name, dropping previous collection
-        _db.dropCollection(_config.outputOptions.finalNamespace);
+        _db.dropCollection(_config.outputOptions.finalNamespace, txn->getWriteConcern());
         BSONObj info;
 
         if (!_db.runCommand("admin",
@@ -613,7 +613,7 @@ long long State::postProcessCollectionNonAtomic(OperationContext* txn,
             uasserted(10076, str::stream() << "rename failed: " << info);
         }
 
-        _db.dropCollection(_config.tempNamespace);
+        _db.dropCollection(_config.tempNamespace, txn->getWriteConcern());
     } else if (_config.outputOptions.outType == Config::MERGE) {
         // merge: upsert new docs into old collection
         {
@@ -632,7 +632,7 @@ long long State::postProcessCollectionNonAtomic(OperationContext* txn,
             Helpers::upsert(_txn, _config.outputOptions.finalNamespace, o);
             pm.hit();
         }
-        _db.dropCollection(_config.tempNamespace);
+        _db.dropCollection(_config.tempNamespace, txn->getWriteConcern());
         pm.finished();
     } else if (_config.outputOptions.outType == Config::REDUCE) {
         // reduce: apply reduce op on new result and existing one
@@ -1287,6 +1287,10 @@ public:
     }
 
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return mrSupportsWriteConcern(cmd);
+    }
+
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
@@ -1301,6 +1305,11 @@ public:
              BSONObjBuilder& result) {
         Timer t;
 
+        // Save and reset the write concern so that it doesn't get changed accidentally by
+        // DBDirectClient.
+        auto oldWC = txn->getWriteConcern();
+        ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
         boost::optional<DisableDocumentValidation> maybeDisableValidation;
         if (shouldBypassDocumentValidationForCommand(cmd))
             maybeDisableValidation.emplace(txn);
@@ -1588,6 +1597,9 @@ public:
     virtual bool slaveOverrideOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
@@ -1609,6 +1621,11 @@ public:
                                      << dbname));
         }
 
+        // Save and reset the write concern so that it doesn't get changed accidentally by
+        // DBDirectClient.
+        auto oldWC = txn->getWriteConcern();
+        ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
         boost::optional<DisableDocumentValidation> maybeDisableValidation;
         if (shouldBypassDocumentValidationForCommand(cmdObj))
             maybeDisableValidation.emplace(txn);
diff --git a/src/mongo/db/commands/mr.h b/src/mongo/db/commands/mr.h
index 04b5f12a661..3d967438179 100644
--- a/src/mongo/db/commands/mr.h
+++ b/src/mongo/db/commands/mr.h
@@ -411,5 +411,11 @@ void addPrivilegesRequiredForMapReduce(Command* commandTemplate,
                                        const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out);
+
+/**
+ * Returns true if the provided mapReduce command has an 'out' parameter.
+ */
+bool mrSupportsWriteConcern(const BSONObj& cmd);
+
 }  // end mr namespace
 }
diff --git a/src/mongo/db/commands/mr_common.cpp b/src/mongo/db/commands/mr_common.cpp
index 4d11661fd2d..d180f276249 100644
--- a/src/mongo/db/commands/mr_common.cpp
+++ b/src/mongo/db/commands/mr_common.cpp
@@ -132,5 +132,15 @@ void addPrivilegesRequiredForMapReduce(Command* commandTemplate,
         out->push_back(Privilege(outputResource, outputActions));
     }
 }
+
+bool mrSupportsWriteConcern(const BSONObj& cmd) {
+    if (!cmd.hasField("out")) {
+        return false;
+    } else if (cmd["out"].type() == Object && cmd["out"].Obj().hasField("inline")) {
+        return false;
+    } else {
+        return true;
+    }
+}
 }
 }
diff --git a/src/mongo/db/commands/oplog_note.cpp b/src/mongo/db/commands/oplog_note.cpp
index 6c96f0907b8..bebf6d4d13c 100644
--- a/src/mongo/db/commands/oplog_note.cpp
+++ b/src/mongo/db/commands/oplog_note.cpp
@@ -54,6 +54,9 @@ public:
     virtual bool adminOnly() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual void help(stringstream& help) const {
         help << "Adds a no-op entry to the oplog";
     }
diff --git a/src/mongo/db/commands/parallel_collection_scan.cpp b/src/mongo/db/commands/parallel_collection_scan.cpp
index 4ca7a131f60..bc280f4b937 100644
--- a/src/mongo/db/commands/parallel_collection_scan.cpp
+++ b/src/mongo/db/commands/parallel_collection_scan.cpp
@@ -58,6 +58,9 @@ public:
 
     ParallelCollectionScanCmd() : Command("parallelCollectionScan") {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/parameters.cpp b/src/mongo/db/commands/parameters.cpp
index 17a85c757b3..c9bc974e040 100644
--- a/src/mongo/db/commands/parameters.cpp
+++ b/src/mongo/db/commands/parameters.cpp
@@ -71,6 +71,9 @@ public:
     virtual bool adminOnly() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
@@ -118,6 +121,9 @@ public:
     virtual bool adminOnly() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
diff --git a/src/mongo/db/commands/pipeline_command.cpp b/src/mongo/db/commands/pipeline_command.cpp
index b04d6ffe1ef..d8836346c5e 100644
--- a/src/mongo/db/commands/pipeline_command.cpp
+++ b/src/mongo/db/commands/pipeline_command.cpp
@@ -53,6 +53,7 @@
 #include "mongo/db/query/get_executor.h"
 #include "mongo/db/storage/storage_options.h"
 #include "mongo/stdx/memory.h"
+#include "mongo/util/scopeguard.h"
 
 namespace mongo {
 
@@ -154,6 +155,9 @@ public:
     PipelineCommand() : Command(Pipeline::commandName) {}  // command is called "aggregate"
 
     // Locks are managed manually, in particular by DocumentSourceCursor.
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return Pipeline::aggSupportsWriteConcern(cmd);
+    }
     virtual bool slaveOk() const {
         return false;
     }
@@ -199,6 +203,11 @@ public:
         if (!pPipeline.get())
             return false;
 
+        // Save and reset the write concern so that it doesn't get changed accidentally by
+        // DBDirectClient.
+        auto oldWC = txn->getWriteConcern();
+        ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
         // This is outside of the if block to keep the object alive until the pipeline is finished.
         BSONObj parsed;
         if (kDebugBuild && !pPipeline->isExplain() && !pCtx->inShard) {
diff --git a/src/mongo/db/commands/plan_cache_commands.cpp b/src/mongo/db/commands/plan_cache_commands.cpp
index 49c25de5514..b7c408f3b3c 100644
--- a/src/mongo/db/commands/plan_cache_commands.cpp
+++ b/src/mongo/db/commands/plan_cache_commands.cpp
@@ -141,6 +141,10 @@ bool PlanCacheCommand::run(OperationContext* txn,
 }
 
 
+bool PlanCacheCommand::supportsWriteConcern(const BSONObj& cmd) const {
+    return false;
+}
+
 bool PlanCacheCommand::slaveOk() const {
     return false;
 }
diff --git a/src/mongo/db/commands/plan_cache_commands.h b/src/mongo/db/commands/plan_cache_commands.h
index f419eaed8eb..87316b84178 100644
--- a/src/mongo/db/commands/plan_cache_commands.h
+++ b/src/mongo/db/commands/plan_cache_commands.h
@@ -64,6 +64,8 @@ public:
              std::string& errmsg,
              BSONObjBuilder& result);
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override;
+
     virtual bool slaveOk() const;
 
     virtual bool slaveOverrideOk() const;
diff --git a/src/mongo/db/commands/rename_collection_cmd.cpp b/src/mongo/db/commands/rename_collection_cmd.cpp
index b2b12c5fed3..eb42664c57b 100644
--- a/src/mongo/db/commands/rename_collection_cmd.cpp
+++ b/src/mongo/db/commands/rename_collection_cmd.cpp
@@ -67,6 +67,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     virtual Status checkAuthForCommand(ClientBasic* client,
                                        const std::string& dbname,
                                        const BSONObj& cmdObj) {
diff --git a/src/mongo/db/commands/repair_cursor.cpp b/src/mongo/db/commands/repair_cursor.cpp
index 8792afe2092..ad8afe526bb 100644
--- a/src/mongo/db/commands/repair_cursor.cpp
+++ b/src/mongo/db/commands/repair_cursor.cpp
@@ -48,6 +48,9 @@ class RepairCursorCmd : public Command {
 public:
     RepairCursorCmd() : Command("repairCursor") {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/server_status.cpp b/src/mongo/db/commands/server_status.cpp
index e7f15f8e4cb..423991bdbfc 100644
--- a/src/mongo/db/commands/server_status.cpp
+++ b/src/mongo/db/commands/server_status.cpp
@@ -67,6 +67,9 @@ public:
     CmdServerStatus()
         : Command("serverStatus", true), _started(curTimeMillis64()), _runCalled(false) {}
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool slaveOk() const {
         return true;
     }
diff --git a/src/mongo/db/commands/shutdown.h b/src/mongo/db/commands/shutdown.h
index 2bb71e7373d..f1f55d0668c 100644
--- a/src/mongo/db/commands/shutdown.h
+++ b/src/mongo/db/commands/shutdown.h
@@ -54,6 +54,9 @@ public:
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out);
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
 protected:
     static void shutdownHelper();
diff --git a/src/mongo/db/commands/snapshot_management.cpp b/src/mongo/db/commands/snapshot_management.cpp
index cb90e41d685..9eec705e4af 100644
--- a/src/mongo/db/commands/snapshot_management.cpp
+++ b/src/mongo/db/commands/snapshot_management.cpp
@@ -45,6 +45,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return true;
     }
@@ -92,6 +95,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return true;
     }
diff --git a/src/mongo/db/commands/test_commands.cpp b/src/mongo/db/commands/test_commands.cpp
index 39b6ef90636..58d554cef84 100644
--- a/src/mongo/db/commands/test_commands.cpp
+++ b/src/mongo/db/commands/test_commands.cpp
@@ -65,6 +65,9 @@ public:
     virtual bool slaveOk() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     // No auth needed because it only works when enabled via command line.
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
@@ -110,6 +113,10 @@ public:
 /* for diagnostic / testing purposes. Enabled via command line. */
 class CmdSleep : public Command {
 public:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
+
     virtual bool adminOnly() const {
         return true;
     }
@@ -204,6 +211,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     // No auth needed because it only works when enabled via command line.
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
@@ -271,6 +281,9 @@ public:
     virtual bool slaveOk() const {
         return false;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
     // No auth needed because it only works when enabled via command line.
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
diff --git a/src/mongo/db/commands/top_command.cpp b/src/mongo/db/commands/top_command.cpp
index 70407d67ea6..e4b788dc711 100644
--- a/src/mongo/db/commands/top_command.cpp
+++ b/src/mongo/db/commands/top_command.cpp
@@ -52,6 +52,9 @@ public:
     virtual bool adminOnly() const {
         return true;
     }
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void help(std::stringstream& help) const {
         help << "usage by collection, in micros ";
     }
diff --git a/src/mongo/db/commands/touch.cpp b/src/mongo/db/commands/touch.cpp
index 530d8937588..520f74e64a1 100644
--- a/src/mongo/db/commands/touch.cpp
+++ b/src/mongo/db/commands/touch.cpp
@@ -57,6 +57,9 @@ using std::stringstream;
 
 class TouchCmd : public Command {
 public:
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual bool adminOnly() const {
         return false;
     }
diff --git a/src/mongo/db/commands/user_management_commands.cpp b/src/mongo/db/commands/user_management_commands.cpp
index 5e35694173e..f058a892a9b 100644
--- a/src/mongo/db/commands/user_management_commands.cpp
+++ b/src/mongo/db/commands/user_management_commands.cpp
@@ -62,12 +62,18 @@
 #include "mongo/db/operation_context.h"
 #include "mongo/db/service_context.h"
 #include "mongo/platform/unordered_set.h"
+#include "mongo/rpc/get_status_from_command_result.h"
 #include "mongo/rpc/protocol.h"
+#include "mongo/s/write_ops/batched_command_response.h"
+#include "mongo/s/write_ops/batched_delete_request.h"
+#include "mongo/s/write_ops/batched_insert_request.h"
+#include "mongo/s/write_ops/batched_update_request.h"
 #include "mongo/stdx/functional.h"
 #include "mongo/stdx/mutex.h"
 #include "mongo/util/log.h"
 #include "mongo/util/mongoutils/str.h"
 #include "mongo/util/net/ssl_manager.h"
+#include "mongo/util/scopeguard.h"
 #include "mongo/util/sequence_util.h"
 #include "mongo/util/time_support.h"
 
@@ -260,24 +266,28 @@ Status insertAuthzDocument(OperationContext* txn,
                            const NamespaceString& collectionName,
                            const BSONObj& document,
                            const BSONObj& writeConcern) {
+    // Save and reset the write concern so that it doesn't get changed accidentally by
+    // DBDirectClient.
+    auto oldWC = txn->getWriteConcern();
+    ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
     try {
         DBDirectClient client(txn);
-        client.insert(collectionName.ns(), document);
 
-        // Handle write concern
-        BSONObjBuilder gleBuilder;
-        gleBuilder.append("getLastError", 1);
-        gleBuilder.appendElements(writeConcern);
+        BatchedInsertRequest req;
+        req.setNS(collectionName);
+        req.addToDocuments(document);
+
         BSONObj res;
-        client.runCommand("admin", gleBuilder.done(), res);
-        string errstr = client.getLastErrorString(res);
-        if (errstr.empty()) {
-            return Status::OK();
-        }
-        if (res.hasField("code") && res["code"].Int() == ASSERT_ID_DUPKEY) {
-            return Status(ErrorCodes::DuplicateKey, errstr);
+        client.runCommand(collectionName.db().toString(), req.toBSON(), res);
+
+        BatchedCommandResponse response;
+        std::string errmsg;
+        response.parseBSON(res, &errmsg);
+        if (errmsg != "") {
+            return Status(ErrorCodes::FailedToParse, errmsg);
         }
-        return Status(ErrorCodes::UnknownError, errstr);
+        return response.toStatus();
     } catch (const DBException& e) {
         return e.toStatus();
     }
@@ -296,23 +306,38 @@ Status updateAuthzDocuments(OperationContext* txn,
                             bool upsert,
                             bool multi,
                             const BSONObj& writeConcern,
-                            int* nMatched) {
+                            long long* nMatched) {
+    // Save and reset the write concern so that it doesn't get changed accidentally by
+    // DBDirectClient.
+    auto oldWC = txn->getWriteConcern();
+    ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
     try {
         DBDirectClient client(txn);
-        client.update(collectionName.ns(), query, updatePattern, upsert, multi);
 
-        // Handle write concern
-        BSONObjBuilder gleBuilder;
-        gleBuilder.append("getLastError", 1);
-        gleBuilder.appendElements(writeConcern);
+        auto doc = stdx::make_unique<BatchedUpdateDocument>();
+        doc->setQuery(query);
+        doc->setUpdateExpr(updatePattern);
+        doc->setMulti(multi);
+        doc->setUpsert(upsert);
+
+        BatchedUpdateRequest req;
+        req.setNS(collectionName);
+        req.addToUpdates(doc.release());
+
         BSONObj res;
-        client.runCommand("admin", gleBuilder.done(), res);
-        string errstr = client.getLastErrorString(res);
-        if (errstr.empty()) {
-            *nMatched = res["n"].numberInt();
-            return Status::OK();
+        client.runCommand(collectionName.db().toString(), req.toBSON(), res);
+
+        BatchedCommandResponse response;
+        std::string errmsg;
+        response.parseBSON(res, &errmsg);
+        if (errmsg != "") {
+            return Status(ErrorCodes::FailedToParse, errmsg);
         }
-        return Status(ErrorCodes::UnknownError, errstr);
+        if (response.getOk()) {
+            *nMatched = response.getN();
+        }
+        return response.toStatus();
     } catch (const DBException& e) {
         return e.toStatus();
     }
@@ -336,7 +361,7 @@ Status updateOneAuthzDocument(OperationContext* txn,
                               const BSONObj& updatePattern,
                               bool upsert,
                               const BSONObj& writeConcern) {
-    int nMatched;
+    long long nMatched;
     Status status = updateAuthzDocuments(
         txn, collectionName, query, updatePattern, upsert, false, writeConcern, &nMatched);
     if (!status.isOK()) {
@@ -359,23 +384,36 @@ Status removeAuthzDocuments(OperationContext* txn,
                             const NamespaceString& collectionName,
                             const BSONObj& query,
                             const BSONObj& writeConcern,
-                            int* numRemoved) {
+                            long long* numRemoved) {
+    // Save and reset the write concern so that it doesn't get changed accidentally by
+    // DBDirectClient.
+    auto oldWC = txn->getWriteConcern();
+    ON_BLOCK_EXIT([txn, oldWC] { txn->setWriteConcern(oldWC); });
+
     try {
         DBDirectClient client(txn);
-        client.remove(collectionName.ns(), query);
 
-        // Handle write concern
-        BSONObjBuilder gleBuilder;
-        gleBuilder.append("getLastError", 1);
-        gleBuilder.appendElements(writeConcern);
+        auto doc = stdx::make_unique<BatchedDeleteDocument>();
+        doc->setQuery(query);
+        doc->setLimit(0);
+
+        BatchedDeleteRequest req;
+        req.setNS(collectionName);
+        req.addToDeletes(doc.release());
+
         BSONObj res;
-        client.runCommand("admin", gleBuilder.done(), res);
-        string errstr = client.getLastErrorString(res);
-        if (errstr.empty()) {
-            *numRemoved = res["n"].numberInt();
-            return Status::OK();
+        client.runCommand(collectionName.db().toString(), req.toBSON(), res);
+
+        BatchedCommandResponse response;
+        std::string errmsg;
+        response.parseBSON(res, &errmsg);
+        if (errmsg != "") {
+            return Status(ErrorCodes::FailedToParse, errmsg);
         }
-        return Status(ErrorCodes::UnknownError, errstr);
+        if (response.getOk()) {
+            *numRemoved = response.getN();
+        }
+        return response.toStatus();
     } catch (const DBException& e) {
         return e.toStatus();
     }
@@ -445,7 +483,7 @@ Status updateRoleDocument(OperationContext* txn,
 Status removeRoleDocuments(OperationContext* txn,
                            const BSONObj& query,
                            const BSONObj& writeConcern,
-                           int* numRemoved) {
+                           long long* numRemoved) {
     Status status = removeAuthzDocuments(
         txn, AuthorizationManager::rolesCollectionNamespace, query, writeConcern, numRemoved);
     if (status.code() == ErrorCodes::UnknownError) {
@@ -518,7 +556,7 @@ Status updatePrivilegeDocument(OperationContext* txn,
 Status removePrivilegeDocuments(OperationContext* txn,
                                 const BSONObj& query,
                                 const BSONObj& writeConcern,
-                                int* numRemoved) {
+                                long long* numRemoved) {
     Status status = removeAuthzDocuments(
         txn, AuthorizationManager::usersCollectionNamespace, query, writeConcern, numRemoved);
     if (status.code() == ErrorCodes::UnknownError) {
@@ -608,6 +646,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Adds a user to the system" << endl;
@@ -750,6 +791,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Used to update a user, for example to change its password" << endl;
@@ -864,6 +908,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Drops a single user." << endl;
@@ -899,7 +946,7 @@ public:
 
         audit::logDropUser(ClientBasic::getCurrent(), userName);
 
-        int nMatched;
+        long long nMatched;
         status = removePrivilegeDocuments(txn,
                                           BSON(AuthorizationManager::USER_NAME_FIELD_NAME
                                                << userName.getUser()
@@ -933,6 +980,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Drops all users for a single database." << endl;
@@ -967,7 +1017,7 @@ public:
 
         audit::logDropAllUsersFromDatabase(ClientBasic::getCurrent(), dbname);
 
-        int numRemoved;
+        long long numRemoved;
         status = removePrivilegeDocuments(txn,
                                           BSON(AuthorizationManager::USER_DB_FIELD_NAME << dbname),
                                           writeConcern,
@@ -992,6 +1042,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Grants roles to a user." << endl;
@@ -1064,6 +1117,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Revokes roles from a user." << endl;
@@ -1138,6 +1194,9 @@ public:
         return true;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     CmdUsersInfo() : Command("usersInfo") {}
 
@@ -1289,6 +1348,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Adds a role to the system" << endl;
@@ -1400,6 +1462,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Used to update a role" << endl;
@@ -1496,6 +1561,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Grants privileges to a role" << endl;
@@ -1601,6 +1669,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Revokes privileges from a role" << endl;
@@ -1714,6 +1785,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Grants roles to another role." << endl;
@@ -1806,6 +1880,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Revokes roles from another role." << endl;
@@ -1892,6 +1969,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Drops a single role.  Before deleting the role completely it must remove it "
@@ -1943,7 +2023,7 @@ public:
         }
 
         // Remove this role from all users
-        int nMatched;
+        long long nMatched;
         status = updateAuthzDocuments(
             txn,
             AuthorizationManager::usersCollectionNamespace,
@@ -2043,6 +2123,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Drops all roles from the given database.  Before deleting the roles completely "
@@ -2080,7 +2163,7 @@ public:
         }
 
         // Remove these roles from all users
-        int nMatched;
+        long long nMatched;
         status = updateAuthzDocuments(
             txn,
             AuthorizationManager::usersCollectionNamespace,
@@ -2163,6 +2246,9 @@ public:
         return true;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     CmdRolesInfo() : Command("rolesInfo") {}
 
@@ -2235,6 +2321,9 @@ public:
         return true;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     CmdInvalidateUserCache() : Command("invalidateUserCache") {}
 
@@ -2271,6 +2360,9 @@ public:
         return true;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
 
     CmdGetCacheGeneration() : Command("_getUserCacheGeneration") {}
 
@@ -2315,6 +2407,9 @@ public:
         return false;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual bool adminOnly() const {
         return true;
@@ -2559,7 +2654,7 @@ public:
         }
 
         if (drop) {
-            int numRemoved;
+            long long numRemoved;
             for (unordered_set<UserName>::iterator it = usersToDrop.begin();
                  it != usersToDrop.end();
                  ++it) {
@@ -2640,7 +2735,7 @@ public:
         }
 
         if (drop) {
-            int numRemoved;
+            long long numRemoved;
             for (unordered_set<RoleName>::iterator it = rolesToDrop.begin();
                  it != rolesToDrop.end();
                  ++it) {
@@ -2897,6 +2992,9 @@ public:
         return true;
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return true;
+    }
 
     virtual void help(stringstream& ss) const {
         ss << "Upgrades the auth data storage schema";
diff --git a/src/mongo/db/commands/validate.cpp b/src/mongo/db/commands/validate.cpp
index e41374cba6a..1569bf5cdcc 100644
--- a/src/mongo/db/commands/validate.cpp
+++ b/src/mongo/db/commands/validate.cpp
@@ -62,6 +62,9 @@ public:
              "Add full:true option to do a more thorough check";
     }
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override {
+        return false;
+    }
     virtual void addRequiredPrivileges(const std::string& dbname,
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {
diff --git a/src/mongo/db/commands/write_commands/batch_executor.cpp b/src/mongo/db/commands/write_commands/batch_executor.cpp
index 51b446532a7..bd71a02d6aa 100644
--- a/src/mongo/db/commands/write_commands/batch_executor.cpp
+++ b/src/mongo/db/commands/write_commands/batch_executor.cpp
@@ -121,19 +121,6 @@ private:
     std::unique_ptr<WriteErrorDetail> _error;
 };
 
-unique_ptr<WCErrorDetail> toWriteConcernError(const Status& wcStatus,
-                                              const WriteConcernResult& wcResult) {
-    auto wcError = stdx::make_unique<WCErrorDetail>();
-
-    wcError->setErrCode(wcStatus.code());
-    wcError->setErrMessage(wcStatus.reason());
-    if (wcResult.wTimedOut) {
-        wcError->setErrInfo(BSON("wtimeout" << true));
-    }
-
-    return wcError;
-}
-
 WriteErrorDetail* toWriteError(const Status& status) {
     WriteErrorDetail* error = new WriteErrorDetail;
 
@@ -278,27 +265,6 @@ void WriteBatchExecutor::executeBatch(const BatchedCommandRequest& request,
     bulkExecute(request, &upserted, &writeErrors);
 
     //
-    // Always try to enforce the write concern, even if everything failed.
-    // If something failed, we have already set the lastOp to be the last op to have succeeded
-    // and written to the oplog.
-
-    {
-        stdx::lock_guard<Client> lk(*_txn->getClient());
-        CurOp::get(_txn)->setMessage_inlock("waiting for write concern");
-    }
-
-    unique_ptr<WCErrorDetail> wcError;
-    WriteConcernResult res;
-    Status status =
-        waitForWriteConcern(_txn,
-                            repl::ReplClientInfo::forClient(_txn->getClient()).getLastOp(),
-                            _txn->getWriteConcern(),
-                            &res);
-    if (!status.isOK()) {
-        wcError = toWriteConcernError(status, res);
-    }
-
-    //
     // Refresh metadata if needed
     //
 
@@ -328,10 +294,6 @@ void WriteBatchExecutor::executeBatch(const BatchedCommandRequest& request,
             response->setErrDetails(writeErrors);
         }
 
-        if (wcError.get()) {
-            response->setWriteConcernError(wcError.release());
-        }
-
         repl::ReplicationCoordinator* replCoord = repl::getGlobalReplicationCoordinator();
         const repl::ReplicationCoordinator::Mode replMode = replCoord->getReplicationMode();
         if (replMode != repl::ReplicationCoordinator::modeNone) {
@@ -743,6 +705,11 @@ void WriteBatchExecutor::execInserts(const BatchedCommandRequest& request,
                                                 &repl::ReplClientInfo::setLastOpToSystemLastOpTime,
                                                 _txn);
 
+    // If this is the local database, don't set last op.
+    if (request.getNS().isLocal()) {
+        lastOpSetterGuard.Dismiss();
+    }
+
     int64_t chunkCount = 0;
     int64_t chunkBytes = 0;
     const int64_t chunkMaxCount = internalQueryExecYieldIterations / 2;
@@ -1047,6 +1014,11 @@ static void multiUpdate(OperationContext* txn,
                                                 &repl::ReplClientInfo::setLastOpToSystemLastOpTime,
                                                 txn);
 
+    // If this is the local database, don't set last op.
+    if (nsString.isLocal()) {
+        lastOpSetterGuard.Dismiss();
+    }
+
     int attempt = 0;
     bool createCollection = false;
     for (int fakeLoop = 0; fakeLoop < 1; fakeLoop++) {
@@ -1226,6 +1198,11 @@ static void multiRemove(OperationContext* txn,
                                                 &repl::ReplClientInfo::setLastOpToSystemLastOpTime,
                                                 txn);
 
+    // If this is the local database, don't set last op.
+    if (nss.isLocal()) {
+        lastOpSetterGuard.Dismiss();
+    }
+
     int attempt = 1;
     while (1) {
         try {
diff --git a/src/mongo/db/commands/write_commands/write_commands.cpp b/src/mongo/db/commands/write_commands/write_commands.cpp
index cd3c13674a1..7e56675ef3c 100644
--- a/src/mongo/db/commands/write_commands/write_commands.cpp
+++ b/src/mongo/db/commands/write_commands/write_commands.cpp
@@ -92,6 +92,10 @@ bool WriteCmd::slaveOk() const {
 }
 
 
+bool WriteCmd::supportsWriteConcern(const BSONObj& cmd) const {
+    return true;
+}
+
 Status WriteCmd::checkAuthForCommand(ClientBasic* client,
                                      const std::string& dbname,
                                      const BSONObj& cmdObj) {
@@ -128,13 +132,6 @@ bool WriteCmd::run(OperationContext* txn,
         return appendCommandStatus(result, Status(ErrorCodes::FailedToParse, errMsg));
     }
 
-    StatusWith<WriteConcernOptions> wcStatus = extractWriteConcern(txn, cmdObj, dbName);
-
-    if (!wcStatus.isOK()) {
-        return appendCommandStatus(result, wcStatus.getStatus());
-    }
-    txn->setWriteConcern(wcStatus.getValue());
-
     WriteBatchExecutor writeBatchExecutor(
         txn, &globalOpCounters, &LastError::get(txn->getClient()));
 
diff --git a/src/mongo/db/commands/write_commands/write_commands.h b/src/mongo/db/commands/write_commands/write_commands.h
index e8dfaaa9608..e01ade2b2ff 100644
--- a/src/mongo/db/commands/write_commands/write_commands.h
+++ b/src/mongo/db/commands/write_commands/write_commands.h
@@ -63,6 +63,8 @@ protected:
 private:
     virtual bool slaveOk() const;
 
+    virtual bool supportsWriteConcern(const BSONObj& cmd) const override;
+
     virtual Status checkAuthForCommand(ClientBasic* client,
                                        const std::string& dbname,
                                        const BSONObj& cmdObj);