diff --git a/include/ircd/fs/aio.h b/include/ircd/fs/aio.h
index 8fa232655..27ad13859 100644
--- a/include/ircd/fs/aio.h
+++ b/include/ircd/fs/aio.h
@@ -25,8 +25,11 @@ namespace ircd::fs::aio
 	struct kernel;
 	struct request;
 
-	extern kernel *context;
 	extern struct stats stats;
+	extern kernel *context;
+
+	extern const bool available_fsync;
+	extern const bool available_fdsync;
 }
 
 /// Statistics structure.
diff --git a/include/ircd/fs/fsync.h b/include/ircd/fs/fsync.h
index 70d64f786..1dc5feaf2 100644
--- a/include/ircd/fs/fsync.h
+++ b/include/ircd/fs/fsync.h
@@ -28,7 +28,7 @@ struct ircd::fs::fsync_opts
 	/// direct syscall is made. Using AIO will only block one ircd::ctx while
 	/// a direct syscall will block the thread (all contexts). If AIO is not
 	/// available or enabled setting this has no effect.
-	bool use_aio {true};
+	bool async {true};
 
 	/// Request priority. This value is ignored by the kernel for the
 	/// operations provided by this interface. It is still provided for
diff --git a/ircd/db.cc b/ircd/db.cc
index 2040ec9b7..f82b4891c 100644
--- a/ircd/db.cc
+++ b/ircd/db.cc
@@ -4458,9 +4458,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fdsync(fd, opts);
 	return Status::OK();
 }
@@ -4507,9 +4505,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fdsync(fd, opts);
 	return Status::OK();
 }
@@ -4554,9 +4550,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fsync(fd, opts);
 	return Status::OK();
 }
@@ -6630,9 +6624,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fsync(fd, opts);
 	return Status::OK();
 }
@@ -6679,9 +6671,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fdsync(fd, opts);
 	return Status::OK();
 }
@@ -6728,9 +6718,7 @@ noexcept try
 	};
 	#endif
 
-	//TODO: AIO fdsync() throwing -EINVAL.
 	fs::fsync_opts opts;
-	opts.use_aio = false;
 	fs::fdsync(fd, opts);
 	return Status::OK();
 }
diff --git a/ircd/fs.cc b/ircd/fs.cc
index 02b35df5b..936d5daf5 100644
--- a/ircd/fs.cc
+++ b/ircd/fs.cc
@@ -406,7 +406,7 @@ ircd::fs::fsync(const fd &fd,
 try
 {
 	#ifdef IRCD_USE_AIO
-	if(likely(aio::context) && opts.use_aio)
+	if(aio::context && opts.async && aio::available_fsync)
 		return aio::fsync(fd, opts);
 	#endif
 
@@ -434,7 +434,7 @@ ircd::fs::fdsync(const fd &fd,
 try
 {
 	#ifdef IRCD_USE_AIO
-	if(likely(aio::context) && opts.use_aio)
+	if(aio::context && opts.async && aio::available_fdsync)
 		return aio::fdsync(fd, opts);
 	#endif
 
@@ -893,15 +893,29 @@ catch(const std::exception &e)
 // fs/aio.h
 //
 
-/// Non-null when aio is available for use
-decltype(ircd::fs::aio::context)
-ircd::fs::aio::context
-{};
-
 /// Global stats structure
 decltype(ircd::fs::aio::stats)
-ircd::fs::aio::stats
-{};
+ircd::fs::aio::stats;
+
+/// Non-null when aio is available for use
+decltype(ircd::fs::aio::context)
+ircd::fs::aio::context;
+
+/// True if IOCB_CMD_FSYNC is supported by AIO. If this is false then
+/// fs::fsync_opts::async=true flag is ignored.
+decltype(ircd::fs::aio::available_fsync)
+ircd::fs::aio::available_fsync
+{
+	false //TODO: Detect kernel support
+};
+
+/// True if IOCB_CMD_FDSYNC is supported by AIO. If this is false then
+/// fs::fsync_opts::async=true flag is ignored.
+decltype(ircd::fs::aio::available_fdsync)
+ircd::fs::aio::available_fdsync
+{
+	false //TODO: Detect kernel support
+};
 
 //
 // init