void sync(char const *path)

Sync now takes a path argument at VFS and File system interfaces.

Issue #1648

repos/dde_rump/src/server/rump_fs/main.cc

@@ -355,7 +355,7 @@ class File_system::Session_component : public Session_rpc_object
 			_handle_registry.sigh(node_handle, sigh);
 		}
 
-		void sync() { rump_sys_sync(); }
+		void sync(Node_handle) override { rump_sys_sync(); }
 };
 
 class File_system::Root : public Root_component<Session_component>

repos/libports/src/lib/libc/vfs_plugin.cc

@@ -715,7 +715,7 @@ int Libc::Vfs_plugin::fcntl(Libc::File_descriptor *fd, int cmd, long arg)
 
 int Libc::Vfs_plugin::fsync(Libc::File_descriptor *fd)
 {
-	_root_dir.sync();
+	_root_dir.sync(fd->fd_path);
 	return 0;
 }
 

repos/libports/src/server/ffat_fs/main.cc

@@ -852,9 +852,6 @@ namespace File_system {
 			{
 				PWRN("File_system::Session::sigh not supported");
 			}
-
-			/* ffat only supports fsync(2) */
-			void sync() { }
 	};
 
 

repos/libports/src/server/fuse_fs/fuse_fs_main.cc

@@ -418,7 +418,7 @@ class File_system::Session_component : public Session_rpc_object
 			_handle_registry.sigh(node_handle, sigh);
 		}
 
-		void sync()
+		void sync(Node_handle) override
 		{
 			Fuse::sync_fs();
 		}

repos/os/include/file_system_session/client.h

@@ -106,9 +106,9 @@ class File_system::Session_client : public Rpc_client<Session>
 			call<Rpc_sigh>(node, sigh);
 		}
 
-		void sync() override
+		void sync(Node_handle node) override
 		{
-			call<Rpc_sync>();
+			call<Rpc_sync>(node);
 		}
 };
 

repos/os/include/file_system_session/file_system_session.h

@@ -289,7 +289,7 @@ struct File_system::Session : public Genode::Session
 	 * cache, which needs to be flushed on certain occasions. Therefore,
 	 * the default implementation just serves as a reminder.
 	 */
-	virtual void sync() { PWRN("sync() not implemented!"); }
+	virtual void sync(Node_handle) { }
 
 
 	/*******************
@@ -328,7 +328,7 @@ struct File_system::Session : public Genode::Session
 	GENODE_RPC_THROW(Rpc_sigh, void, sigh,
 	                 GENODE_TYPE_LIST(Invalid_handle),
 	                 Node_handle, Signal_context_capability);
-	GENODE_RPC(Rpc_sync, void, sync);
+	GENODE_RPC(Rpc_sync, void, sync, Node_handle);
 
 	/*
 	 * Manual type-list definition, needed because the RPC interface

repos/os/include/vfs/dir_file_system.h

@@ -514,10 +514,20 @@ class Vfs::Dir_file_system : public File_system
 		/**
 		 * Synchronize all file systems
 		 */
-		void sync() override
+		void sync(char const *path) override
 		{
+			if (strcmp("/", path, 2) == 0) {
+				for (File_system *fs = _first_file_system; fs; fs = fs->next)
+					fs->sync("/");
+				return;
+			}
+
+			path = _sub_path(path);
+			if (!path)
+				return;
+
 			for (File_system *fs = _first_file_system; fs; fs = fs->next)
-				fs->sync();
+				fs->sync(path);
 		}
 
 

repos/os/include/vfs/file_system.h

@@ -32,11 +32,9 @@ struct Vfs::File_system : Directory_service, File_io_service
 	/**
 	 * Synchronize file system
 	 *
-	 * This method is only used by a Fs_file_system because such a file
-	 * system may employ a backend, which maintains a internal cache, that
-	 * needs to be flushed.
+	 * This method flushes any delayed operations from the file system.
 	 */
-	virtual void sync() { }
+	virtual void sync(char const *path) { }
 };
 
 #endif /* _INCLUDE__VFS__FILE_SYSTEM_H_ */

repos/os/include/vfs/fs_file_system.h

@@ -568,9 +568,13 @@ class Vfs::Fs_file_system : public File_system
 
 		static char const *name() { return "fs"; }
 
-		void sync() override
+		void sync(char const *path) override
 		{
-			_fs.sync();
+			try {
+				::File_system::Node_handle node = _fs.node(path);
+				Fs_handle_guard node_guard(_fs, node);
+				_fs.sync(node);
+			} catch (...) { }
 		}
 
 

repos/os/include/vfs/ram_file_system.h

@@ -57,8 +57,6 @@ class Vfs::Ram_file_system : public File_system, private ::File_system::Director
 
 		static char const *name() { return "ram"; }
 
-		void sync() { }
-
 		/********************************
 		 ** File I/O service interface **
 		 ********************************/

repos/os/src/server/lx_fs/main.cc

@@ -311,7 +311,7 @@ class File_system::Session_component : public Session_rpc_object
 		 * reminder because besides testing, there is currently no
 		 * use-case.
 		 */
-		void sync() { PWRN("sync() not implemented!"); }
+		void sync(Node_handle) override { PWRN("sync() not implemented!"); }
 };
 
 

repos/os/src/server/ram_fs/main.cc

@@ -408,8 +408,6 @@ namespace File_system {
 			{
 				_handle_registry.sigh(node_handle, sigh);
 			}
-
-			void sync() { }
 	};
 
 

repos/os/src/server/tar_fs/main.cc

@@ -440,9 +440,6 @@ namespace File_system {
 			{
 				PWRN("File_system::Session::sigh not supported");
 			}
-
-			/* merely readonly, no need to sync */
-			void sync() { }
 	};
 
 

repos/os/src/server/trace_fs/main.cc

@@ -914,8 +914,6 @@ class File_system::Session_component : public Session_rpc_object
 
 		void sigh(Node_handle node_handle, Signal_context_capability sigh) {
 			_handle_registry.sigh(node_handle, sigh); }
-
-		void sync() { }
 };
 
 

repos/ports/src/noux/main.cc

@@ -835,7 +835,7 @@ bool Noux::Child::syscall(Noux::Session::Syscall sc)
 
 		case SYSCALL_SYNC:
 			{
-				root_dir()->sync();
+				root_dir()->sync("/");
 				result = true;
 				break;
 			}