unix: fsmount fspick fsopen linux syscall

Patches were submitted to Linux manpages:
https://lwn.net/Articles/802096/, but not yet applied.
Generated on linux kernel v5.16.

Fsconfig couldn't implemented by generator, it requires
special cases handling.

Change-Id: I7f9560f4bc5b4bbe1e00c63ce1bc25c781aa1293
Reviewed-on: https://go-review.googlesource.com/c/sys/+/398434
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Benny Siegert <bsiegert@gmail.com>

unix/linux/types.go

@@ -914,6 +914,15 @@ const (
 	MOVE_MOUNT_T_AUTOMOUNTS = C.MOVE_MOUNT_T_AUTOMOUNTS
 	MOVE_MOUNT_T_EMPTY_PATH = C.MOVE_MOUNT_T_EMPTY_PATH
 	MOVE_MOUNT_SET_GROUP    = C.MOVE_MOUNT_SET_GROUP
+
+	FSOPEN_CLOEXEC = C.FSOPEN_CLOEXEC
+
+	FSPICK_CLOEXEC          = C.FSPICK_CLOEXEC
+	FSPICK_SYMLINK_NOFOLLOW = C.FSPICK_SYMLINK_NOFOLLOW
+	FSPICK_NO_AUTOMOUNT     = C.FSPICK_NO_AUTOMOUNT
+	FSPICK_EMPTY_PATH       = C.FSPICK_EMPTY_PATH
+
+	FSMOUNT_CLOEXEC = C.FSMOUNT_CLOEXEC
 )
 
 type OpenHow C.struct_open_how

unix/syscall_linux.go

@@ -1829,6 +1829,9 @@ func Dup2(oldfd, newfd int) error {
 //sys	Fremovexattr(fd int, attr string) (err error)
 //sys	Fsetxattr(fd int, attr string, dest []byte, flags int) (err error)
 //sys	Fsync(fd int) (err error)
+//sys	Fsmount(fd int, flags int, mountAttrs int) (fsfd int, err error)
+//sys	Fsopen(fsName string, flags int) (fd int, err error)
+//sys	Fspick(dirfd int, pathName string, flags int) (fd int, err error)
 //sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
 //sysnb	Getpgid(pid int) (pgid int, err error)
 

unix/zsyscall_linux.go

@@ -828,6 +828,49 @@ func Fsync(fd int) (err error) {
 
 // THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
 
+func Fsmount(fd int, flags int, mountAttrs int) (fsfd int, err error) {
+	r0, _, e1 := Syscall(SYS_FSMOUNT, uintptr(fd), uintptr(flags), uintptr(mountAttrs))
+	fsfd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fsopen(fsName string, flags int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(fsName)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_FSOPEN, uintptr(unsafe.Pointer(_p0)), uintptr(flags), 0)
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
+func Fspick(dirfd int, pathName string, flags int) (fd int, err error) {
+	var _p0 *byte
+	_p0, err = BytePtrFromString(pathName)
+	if err != nil {
+		return
+	}
+	r0, _, e1 := Syscall(SYS_FSPICK, uintptr(dirfd), uintptr(unsafe.Pointer(_p0)), uintptr(flags))
+	fd = int(r0)
+	if e1 != 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
+// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT
+
 func Getdents(fd int, buf []byte) (n int, err error) {
 	var _p0 unsafe.Pointer
 	if len(buf) > 0 {

unix/ztypes_linux.go

@@ -764,6 +764,15 @@ const (
 	MOVE_MOUNT_T_AUTOMOUNTS = 0x20
 	MOVE_MOUNT_T_EMPTY_PATH = 0x40
 	MOVE_MOUNT_SET_GROUP    = 0x100
+
+	FSOPEN_CLOEXEC = 0x1
+
+	FSPICK_CLOEXEC          = 0x1
+	FSPICK_SYMLINK_NOFOLLOW = 0x2
+	FSPICK_NO_AUTOMOUNT     = 0x4
+	FSPICK_EMPTY_PATH       = 0x8
+
+	FSMOUNT_CLOEXEC = 0x1
 )
 
 type OpenHow struct {