From 7e58a0df8b994e4a3a53aec88dc05fe7f1b079bf Mon Sep 17 00:00:00 2001 From: Paul Buetow Date: Sun, 31 May 2026 10:21:57 +0300 Subject: test(mountfs): exercise fsopen end-to-end in mount-API scenario The mountfs-management integration scenario covered the new mount API syscalls fsmount/move_mount/mount/umount/pivot_root but not fsopen, the API's entry point and a direct eventfd-kind sibling of fsmount. Add a best-effort fsopen("tmpfs", FSOPEN_CLOEXEC) call (closing the returned context fd on success) and assert enter_fsopen is traced. fsopen's tracing is otherwise correct: args[1] flags captured, args[0] fsname (a filesystem TYPE, not a path) deliberately not treated as a pathname, returned fd registered as the 'fsopenfd:' descriptor. Co-Authored-By: Claude Opus 4.8 --- cmd/ioworkload/scenario_mountfs.go | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'cmd') diff --git a/cmd/ioworkload/scenario_mountfs.go b/cmd/ioworkload/scenario_mountfs.go index 4c48ded..7aa8163 100644 --- a/cmd/ioworkload/scenario_mountfs.go +++ b/cmd/ioworkload/scenario_mountfs.go @@ -46,6 +46,13 @@ func mountfsManagement() error { // Best-effort coverage: these calls are expected to fail on most hosts // without CAP_SYS_ADMIN, but still exercise syscall tracing paths. + // fsopen(fsname, flags) is the entry point of the new mount API: it takes a + // filesystem TYPE name (e.g. "tmpfs"), NOT a path, in args[0] and the + // FSOPEN_CLOEXEC flag in args[1], returning a new filesystem-context fd. We + // close the returned fd when the call succeeds so we do not leak it. + if fd, _, errno := syscall.RawSyscall(unix.SYS_FSOPEN, uintptr(unsafe.Pointer(tmpfs)), uintptr(unix.FSOPEN_CLOEXEC), 0); errno == 0 { + _ = syscall.Close(int(fd)) + } _, _, _ = syscall.RawSyscall6(unix.SYS_MOUNT, uintptr(unsafe.Pointer(none)), uintptr(unsafe.Pointer(mountPath)), uintptr(unsafe.Pointer(tmpfs)), 0, 0, 0) _, _, _ = syscall.RawSyscall(unix.SYS_UMOUNT2, uintptr(unsafe.Pointer(mountPath)), 0, 0) _, _, _ = syscall.RawSyscall(unix.SYS_UMOUNT2, uintptr(unsafe.Pointer(mountPath)), uintptr(unix.MNT_DETACH), 0) -- cgit v1.2.3