SERVER-22245 implement storage engine API changes for readOnly mode

9 files changed, 44 insertions, 8 deletions

diff --git a/jstests/noPassthrough/read_only_command_line.js b/jstests/noPassthrough/read_only_command_line.js
index c7eb52a1de3..9da9b559e98 100644
--- a/jstests/noPassthrough/read_only_command_line.js
+++ b/jstests/noPassthrough/read_only_command_line.js
@@ -12,8 +12,10 @@
     assert(!mongod.getDB("admin").serverStatus().storageEngine.readOnly);
     MongoRunner.stopMongod(mongod);
 
-    mongod = MongoRunner.runMongod({readOnly: ""});
-    assert(mongod.getDB("admin").isMaster().readOnly);
-    assert(mongod.getDB("admin").serverStatus().storageEngine.readOnly);
-    MongoRunner.stopMongod(mongod);
+    // TODO: uncomment when readOnly mode is implemented in mmapv1.
+    //
+    // mongod = MongoRunner.runMongod({readOnly: ""});
+    // assert(mongod.getDB("admin").isMaster().readOnly);
+    // assert(mongod.getDB("admin").serverStatus().storageEngine.readOnly);
+    // MongoRunner.stopMongod(mongod);
 }());
diff --git a/src/mongo/db/operation_context.h b/src/mongo/db/operation_context.h
index 3a7e3165dda..249b89bdf37 100644
--- a/src/mongo/db/operation_context.h
+++ b/src/mongo/db/operation_context.h
@@ -30,8 +30,9 @@
 
 #include "mongo/base/disallow_copying.h"
 #include "mongo/base/status.h"
-#include "mongo/db/storage/recovery_unit.h"
 #include "mongo/db/concurrency/d_concurrency.h"
+#include "mongo/db/storage/recovery_unit.h"
+#include "mongo/db/storage/storage_options.h"
 #include "mongo/db/write_concern_options.h"
 #include "mongo/platform/atomic_word.h"
 #include "mongo/util/decorable.h"
@@ -239,6 +240,9 @@ public:
         : _txn(txn),
           _committed(false),
           _toplevel(txn->_ruState == OperationContext::kNotInUnitOfWork) {
+        uassert(ErrorCodes::IllegalOperation,
+                "Cannot execute a write operation in read-only mode",
+                !storageGlobalParams.readOnly);
         _txn->lockState()->beginWriteUnitOfWork();
         if (_toplevel) {
             _txn->recoveryUnit()->beginUnitOfWork(_txn);
@@ -247,6 +251,7 @@ public:
     }
 
     ~WriteUnitOfWork() {
+        dassert(!storageGlobalParams.readOnly);
         if (!_committed) {
             invariant(_txn->_ruState != OperationContext::kNotInUnitOfWork);
             if (_toplevel) {
diff --git a/src/mongo/db/service_context_d.cpp b/src/mongo/db/service_context_d.cpp
index aa3a0181165..0a5965c03b8 100644
--- a/src/mongo/db/service_context_d.cpp
+++ b/src/mongo/db/service_context_d.cpp
@@ -140,6 +140,14 @@ void ServiceContextMongoD::initializeGlobalStorageEngine() {
                           << storageGlobalParams.engine,
             factory);
 
+    if (storageGlobalParams.readOnly) {
+        uassert(34368,
+                str::stream()
+                    << "Server was started in read-only mode, but the configured storage engine, "
+                    << storageGlobalParams.engine << ", does not support read-only operation",
+                factory->supportsReadOnly());
+    }
+
     std::unique_ptr<StorageEngineMetadata> metadata = StorageEngineMetadata::forPath(dbpath);
 
     // Validate options in metadata against current startup options.
diff --git a/src/mongo/db/storage/SConscript b/src/mongo/db/storage/SConscript
index 1215d5afbbd..d0468f266e1 100644
--- a/src/mongo/db/storage/SConscript
+++ b/src/mongo/db/storage/SConscript
@@ -95,6 +95,7 @@ env.Library(
         'sorted_data_interface_test_unindex.cpp',
     ],
     LIBDEPS=[
+        '$BUILD_DIR/mongo/db/storage/storage_options',
         '$BUILD_DIR/mongo/db/service_context',
         '$BUILD_DIR/mongo/unittest/unittest',
         'index_entry_comparison',
@@ -128,8 +129,9 @@ env.Library(
         'record_store_test_validate.cpp',
         ],
     LIBDEPS=[
-        '$BUILD_DIR/mongo/unittest/unittest',
         '$BUILD_DIR/mongo/db/service_context',
+        '$BUILD_DIR/mongo/db/storage/storage_options',
+        '$BUILD_DIR/mongo/unittest/unittest',
         ],
     LIBDEPS_TAGS=[
         # Depends on newHarnessHelper, which does not have a unique definition
diff --git a/src/mongo/db/storage/ephemeral_for_test/SConscript b/src/mongo/db/storage/ephemeral_for_test/SConscript
index 0b4c4729200..7d535228988 100644
--- a/src/mongo/db/storage/ephemeral_for_test/SConscript
+++ b/src/mongo/db/storage/ephemeral_for_test/SConscript
@@ -66,7 +66,8 @@ env.CppUnitTest(
     source=['ephemeral_for_test_engine_test.cpp',
             ],
     LIBDEPS=[
-        'storage_ephemeral_for_test_core',
         '$BUILD_DIR/mongo/db/storage/kv/kv_engine_test_harness',
+        '$BUILD_DIR/mongo/db/storage/storage_options',
+        'storage_ephemeral_for_test_core',
         ],
     )
diff --git a/src/mongo/db/storage/kv/SConscript b/src/mongo/db/storage/kv/SConscript
index de8e5d25d64..a9d538dca46 100644
--- a/src/mongo/db/storage/kv/SConscript
+++ b/src/mongo/db/storage/kv/SConscript
@@ -41,6 +41,7 @@ env.Library(
     LIBDEPS=[
         '$BUILD_DIR/mongo/base',
         '$BUILD_DIR/mongo/db/storage/kv/kv_engine_core',
+        '$BUILD_DIR/mongo/db/storage/storage_options',
         'kv_database_catalog_entry_core',
     ],
 )
@@ -71,6 +72,7 @@ env.Library(
         'kv_database_catalog_entry_get_index_mock.cpp'
         ],
     LIBDEPS=[
+        '$BUILD_DIR/mongo/db/storage/storage_options',
         'kv_database_catalog_entry_core',
         'kv_engine_core',
         'kv_storage_engine',
diff --git a/src/mongo/db/storage/mmap_v1/SConscript b/src/mongo/db/storage/mmap_v1/SConscript
index 42832eb115a..8f8d4343300 100644
--- a/src/mongo/db/storage/mmap_v1/SConscript
+++ b/src/mongo/db/storage/mmap_v1/SConscript
@@ -118,11 +118,12 @@ env.Library(
         'record_store_v1_simple_iterator.cpp',
         ],
     LIBDEPS= [
-        'extent',
         '$BUILD_DIR/mongo/db/commands/server_status_core',
         '$BUILD_DIR/mongo/db/service_context',
+        '$BUILD_DIR/mongo/db/storage/storage_options',
         '$BUILD_DIR/mongo/util/concurrency/spin_lock',
         '$BUILD_DIR/mongo/util/progress_meter',
+        'extent',
         ]
     )
 
diff --git a/src/mongo/db/storage/mmap_v1/mmap_v1_init.cpp b/src/mongo/db/storage/mmap_v1/mmap_v1_init.cpp
index 88667959dd3..832cc059ec8 100644
--- a/src/mongo/db/storage/mmap_v1/mmap_v1_init.cpp
+++ b/src/mongo/db/storage/mmap_v1/mmap_v1_init.cpp
@@ -68,6 +68,10 @@ public:
         builder.appendBool("directoryPerDB", params.directoryperdb);
         return builder.obj();
     }
+
+    bool supportsReadOnly() const override {
+        return true;
+    }
 };
 
 }  // namespace
diff --git a/src/mongo/db/storage/storage_engine.h b/src/mongo/db/storage/storage_engine.h
index 1cedafc2ba8..b31a296ac89 100644
--- a/src/mongo/db/storage/storage_engine.h
+++ b/src/mongo/db/storage/storage_engine.h
@@ -122,6 +122,17 @@ public:
          * on restart.
          */
         virtual BSONObj createMetadataOptions(const StorageGlobalParams& params) const = 0;
+
+        /**
+         * Returns whether the engine supports read-only mode. If read-only mode is enabled, the
+         * engine may be started on a read-only filesystem (either mounted read-only or with
+         * read-only permissions). If readOnly mode is enabled, it is undefined behavior to call
+         * methods that write data (e.g. insertRecord). This method is provided on the Factory
+         * because it must be called before the storageEngine is instantiated.
+         */
+        virtual bool supportsReadOnly() const {
+            return false;
+        }
     };
 
     /**