savedata: scoped filesystem sync

Utilities/File.cpp

@@ -1892,11 +1892,29 @@ bool fs::utime(const std::string& path, s64 atime, s64 mtime)
 #endif
 }
 
-void fs::sync()
+void fs::sync(const std::string& path)
 {
 #ifdef _WIN32
+	static_cast<void>(path);
 	fs::g_tls_error = fs::error::unknown;
+#elif defined(__linux__)
+	// Only flush the filesystem containing the path: a global sync() also waits on every other mounted
+	// filesystem and may block indefinitely on a slow or stalled one (e.g. network or FUSE mounts)
+	const int fd = ::open(path.c_str(), O_RDONLY | O_CLOEXEC);
+
+	if (fd == -1)
+	{
+		fs::g_tls_error = to_error(errno);
+		return;
+	}
+
+	const int res = ::syncfs(fd);
+	const int err = errno;
+	::close(fd);
+
+	fs::g_tls_error = res == 0 ? fs::error::ok : to_error(err);
 #else
+	static_cast<void>(path);
 	::sync();
 	fs::g_tls_error = fs::error::ok;
 #endif

Utilities/File.h

@@ -263,8 +263,8 @@ namespace fs
 	// Set file access/modification time
 	bool utime(const std::string& path, s64 atime, s64 mtime);
 
-	// Synchronize filesystems (TODO)
-	void sync();
+	// Synchronize the filesystem containing the given path (only that filesystem where supported)
+	void sync(const std::string& path);
 
 	class file final
 	{

rpcs3/Emu/Cell/Modules/cellSaveData.cpp

@@ -2189,7 +2189,14 @@ static NEVER_INLINE error_code savedata_op(ppu_thread& ppu, u32 operation, u32 v
 
 		// Remove old backup
 		fs::remove_all(old_path);
-		fs::sync();
+		fs::sync(new_path);
+
+#ifndef _WIN32
+		if (fs::g_tls_error != fs::error::ok)
+		{
+			cellSaveData.warning("savedata_op(): Failed to sync filesystem of '%s' (%s)", new_path, fs::g_tls_error);
+		}
+#endif
 
 		// Backup old savedata
 		if (!vfs::host::rename(dir_path, old_path, &g_mp_sys_dev_hdd0, false))

rpcs3/Emu/VFS.cpp

@@ -1094,6 +1094,10 @@ bool vfs::host::rename(const std::string& from, const std::string& to, const lv2
 
 	bool res = false;
 
+	const auto retry_start = std::chrono::steady_clock::now();
+	auto retry_report = retry_start;
+	u64 retry_count = 0;
+
 	for (;; std::this_thread::yield())
 	{
 		if (fs::rename(from, to, overwrite))
@@ -1107,6 +1111,16 @@ bool vfs::host::rename(const std::string& from, const std::string& to, const lv2
 			res = false;
 			break;
 		}
+
+		retry_count++;
+
+		// Report a retry loop which is taking long, it may never end if the error is persistent
+		if (const auto now = std::chrono::steady_clock::now(); now - retry_report >= std::chrono::seconds(1))
+		{
+			retry_report = now;
+			vfs_log.warning("vfs::host::rename(): Still retrying after %u attempts and %u ms (from='%s', to='%s', error=%s)", retry_count,
+				static_cast<u64>(std::chrono::duration_cast<std::chrono::milliseconds>(now - retry_start).count()), from, to, fs::g_tls_error);
+		}
 	}
 
 	const auto fs_error = fs::g_tls_error;