Index: head/lib/libc/sys/Makefile.inc
===================================================================
--- head/lib/libc/sys/Makefile.inc	(revision 304286)
+++ head/lib/libc/sys/Makefile.inc	(revision 304287)
@@ -1,466 +1,467 @@
 #	@(#)Makefile.inc	8.3 (Berkeley) 10/24/94
 # $FreeBSD$
 
 # sys sources
 .PATH: ${LIBC_SRCTOP}/${LIBC_ARCH}/sys ${LIBC_SRCTOP}/sys
 
 # Include the generated makefile containing the *complete* list
 # of syscall names in MIASM.
 .include "${LIBC_SRCTOP}/../../sys/sys/syscall.mk"
 
 # Include machine dependent definitions.
 #
 # MDASM names override the default syscall names in MIASM.
 # NOASM will prevent the default syscall code from being generated.
 #
 .sinclude "${LIBC_SRCTOP}/${LIBC_ARCH}/sys/Makefile.inc"
 
 SRCS+= clock_gettime.c gettimeofday.c __vdso_gettimeofday.c
 NOASM+=  clock_gettime.o gettimeofday.o
 PSEUDO+= _clock_gettime.o _gettimeofday.o
 
 # Sources common to both syscall interfaces:
 SRCS+=	\
 	__error.c \
 	interposing_table.c
 
 SRCS+= futimens.c utimensat.c
 NOASM+= futimens.o utimensat.o
 PSEUDO+= _futimens.o _utimensat.o
 
 SRCS+= pipe.c
 
 INTERPOSED = \
 	accept \
 	accept4 \
 	aio_suspend \
 	close \
 	connect \
 	fcntl \
 	fdatasync \
 	fsync \
 	fork \
 	kevent \
 	msync \
 	nanosleep \
 	open \
 	openat \
 	poll \
 	ppoll \
 	pselect \
 	read \
 	readv \
 	recvfrom \
 	recvmsg \
 	select \
 	sendmsg \
 	sendto \
 	setcontext \
 	sigprocmask \
 	sigsuspend \
 	sigtimedwait \
 	sigwait \
 	sigwaitinfo \
 	swapcontext \
 	wait4 \
 	wait6 \
 	write \
 	writev
 
 .if ${MACHINE_CPUARCH} == "sparc64"
 SRCS+=	sigaction.c
 NOASM+=	sigaction.o
 .else
 INTERPOSED+= sigaction
 .endif
 
 SRCS+=	${INTERPOSED:S/$/.c/}
 NOASM+=	${INTERPOSED:S/$/.o/}
 PSEUDO+=	${INTERPOSED:C/^.*$/_&.o/}
 
 # Add machine dependent asm sources:
 SRCS+=${MDASM}
 
 # Look though the complete list of syscalls (MIASM) for names that are
 # not defined with machine dependent implementations (MDASM) and are
 # not declared for no generation of default code (NOASM).  Add each
 # syscall that satisfies these conditions to the ASM list.
 .for _asm in ${MIASM}
 .if (${MDASM:R:M${_asm:R}} == "")
 .if (${NOASM:R:M${_asm:R}} == "")
 ASM+=$(_asm)
 .endif
 .endif
 .endfor
 
 SASM=	${ASM:S/.o/.S/}
 
 SPSEUDO= ${PSEUDO:S/.o/.S/}
 
 SRCS+=	${SASM} ${SPSEUDO}
 
 SYM_MAPS+=	${LIBC_SRCTOP}/sys/Symbol.map
 
 # Generated files
 CLEANFILES+=	${SASM} ${SPSEUDO}
 
 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386" || \
     ${MACHINE_CPUARCH} == "powerpc" || ${MACHINE_ARCH:Marmv6*}
 NOTE_GNU_STACK='\t.section .note.GNU-stack,"",%%progbits\n'
 .else
 NOTE_GNU_STACK=''
 .endif
 
 ${SASM}:
 	printf '#include "compat.h"\n' > ${.TARGET}
 	printf '#include "SYS.h"\nRSYSCALL(${.PREFIX})\n' >> ${.TARGET}
 	printf  ${NOTE_GNU_STACK} >>${.TARGET}
 
 ${SPSEUDO}:
 	printf '#include "compat.h"\n' > ${.TARGET}
 	printf '#include "SYS.h"\nPSEUDO(${.PREFIX:S/_//})\n' \
 	    >> ${.TARGET}
 	printf ${NOTE_GNU_STACK} >>${.TARGET}
 
 MAN+=	abort2.2 \
 	accept.2 \
 	access.2 \
 	acct.2 \
 	adjtime.2 \
 	aio_cancel.2 \
 	aio_error.2 \
 	aio_fsync.2 \
 	aio_mlock.2 \
 	aio_read.2 \
 	aio_return.2 \
 	aio_suspend.2 \
 	aio_waitcomplete.2 \
 	aio_write.2 \
 	bind.2 \
 	bindat.2 \
 	brk.2 \
 	cap_enter.2 \
 	cap_fcntls_limit.2 \
 	cap_ioctls_limit.2 \
 	cap_rights_limit.2 \
 	chdir.2 \
 	chflags.2 \
 	chmod.2 \
 	chown.2 \
 	chroot.2 \
 	clock_gettime.2 \
 	close.2 \
 	closefrom.2 \
 	connect.2 \
 	connectat.2 \
 	cpuset.2 \
 	cpuset_getaffinity.2 \
 	dup.2 \
 	execve.2 \
 	_exit.2 \
 	extattr_get_file.2 \
 	fcntl.2 \
 	ffclock.2 \
 	fhopen.2 \
 	flock.2 \
 	fork.2 \
 	fsync.2 \
 	getdirentries.2 \
 	getdtablesize.2 \
 	getfh.2 \
 	getfsstat.2 \
 	getgid.2 \
 	getgroups.2 \
 	getitimer.2 \
 	getlogin.2 \
 	getloginclass.2 \
 	getpeername.2 \
 	getpgrp.2 \
 	getpid.2 \
 	getpriority.2 \
 	getrlimit.2 \
 	getrusage.2 \
 	getsid.2 \
 	getsockname.2 \
 	getsockopt.2 \
 	gettimeofday.2 \
 	getuid.2 \
 	intro.2 \
 	ioctl.2 \
 	issetugid.2 \
 	jail.2 \
 	kenv.2 \
 	kill.2 \
 	kldfind.2 \
 	kldfirstmod.2 \
 	kldload.2 \
 	kldnext.2 \
 	kldstat.2 \
 	kldsym.2 \
 	kldunload.2 \
 	kqueue.2 \
 	ktrace.2 \
 	link.2 \
 	lio_listio.2 \
 	listen.2 \
 	lseek.2 \
 	madvise.2 \
 	mincore.2 \
 	minherit.2 \
 	mkdir.2 \
 	mkfifo.2 \
 	mknod.2 \
 	mlock.2 \
 	mlockall.2 \
 	mmap.2 \
 	modfind.2 \
 	modnext.2 \
 	modstat.2 \
 	mount.2 \
 	mprotect.2 \
 	mq_close.2 \
 	mq_getattr.2 \
 	mq_notify.2 \
 	mq_open.2 \
 	mq_receive.2 \
 	mq_send.2 \
 	mq_setattr.2 \
 	msgctl.2 \
 	msgget.2 \
 	msgrcv.2 \
 	msgsnd.2 \
 	msync.2 \
 	munmap.2 \
 	nanosleep.2 \
 	nfssvc.2 \
 	ntp_adjtime.2 \
 	numa_getaffinity.2 \
 	open.2 \
 	pathconf.2 \
 	pdfork.2 \
 	pipe.2 \
 	poll.2 \
 	posix_fadvise.2 \
 	posix_fallocate.2 \
 	posix_openpt.2 \
 	procctl.2 \
 	profil.2 \
 	pselect.2 \
 	ptrace.2 \
 	quotactl.2 \
 	read.2 \
 	readlink.2 \
 	reboot.2 \
 	recv.2 \
 	rename.2 \
 	revoke.2 \
 	rfork.2 \
 	rmdir.2 \
 	rtprio.2
 .if !defined(NO_P1003_1B)
 MAN+=	sched_get_priority_max.2 \
 	sched_setparam.2 \
 	sched_setscheduler.2 \
 	sched_yield.2
 .endif
 MAN+=	sctp_generic_recvmsg.2 \
 	sctp_generic_sendmsg.2 \
 	sctp_peeloff.2 \
 	select.2 \
 	semctl.2 \
 	semget.2 \
 	semop.2 \
 	send.2 \
 	setfib.2 \
 	sendfile.2 \
 	setgroups.2 \
 	setpgid.2 \
 	setregid.2 \
 	setresuid.2 \
 	setreuid.2 \
 	setsid.2 \
 	setuid.2 \
 	shmat.2 \
 	shmctl.2 \
 	shmget.2 \
 	shm_open.2 \
 	shutdown.2 \
 	sigaction.2 \
 	sigaltstack.2 \
 	sigpending.2 \
 	sigprocmask.2 \
 	sigqueue.2 \
 	sigreturn.2 \
 	sigstack.2 \
 	sigsuspend.2 \
 	sigwait.2 \
 	sigwaitinfo.2 \
 	socket.2 \
 	socketpair.2 \
 	stat.2 \
 	statfs.2 \
 	swapon.2 \
 	symlink.2 \
 	sync.2 \
 	sysarch.2 \
 	syscall.2 \
 	thr_exit.2 \
 	thr_kill.2 \
 	thr_new.2 \
 	thr_self.2 \
 	thr_set_name.2 \
 	timer_create.2 \
 	timer_delete.2 \
 	timer_settime.2 \
 	truncate.2 \
 	umask.2 \
 	undelete.2 \
 	unlink.2 \
 	utimensat.2 \
 	utimes.2 \
 	utrace.2 \
 	uuidgen.2 \
 	vfork.2 \
 	wait.2 \
 	write.2 \
 	_umtx_op.2
 
 MLINKS+=accept.2 accept4.2
 MLINKS+=access.2 eaccess.2 \
 	access.2 faccessat.2
 MLINKS+=brk.2 sbrk.2
 MLINKS+=cap_enter.2 cap_getmode.2
 MLINKS+=cap_fcntls_limit.2 cap_fcntls_get.2
 MLINKS+=cap_ioctls_limit.2 cap_ioctls_get.2
 MLINKS+=cap_rights_limit.2 cap_rights_get.2
 MLINKS+=chdir.2 fchdir.2
 MLINKS+=chflags.2 chflagsat.2 \
 	chflags.2 fchflags.2 \
 	chflags.2 lchflags.2
 MLINKS+=chmod.2 fchmod.2 \
 	chmod.2 fchmodat.2 \
 	chmod.2 lchmod.2
 MLINKS+=chown.2 fchown.2 \
 	chown.2 fchownat.2 \
 	chown.2 lchown.2
 MLINKS+=clock_gettime.2 clock_getres.2 \
 	clock_gettime.2 clock_settime.2
 MLINKS+=cpuset.2 cpuset_getid.2 \
 	cpuset.2 cpuset_setid.2
 MLINKS+=cpuset_getaffinity.2 cpuset_setaffinity.2
 MLINKS+=dup.2 dup2.2
 MLINKS+=execve.2 fexecve.2
 MLINKS+=extattr_get_file.2 extattr.2 \
 	extattr_get_file.2 extattr_delete_fd.2 \
 	extattr_get_file.2 extattr_delete_file.2 \
 	extattr_get_file.2 extattr_delete_link.2 \
 	extattr_get_file.2 extattr_get_fd.2 \
 	extattr_get_file.2 extattr_get_link.2 \
 	extattr_get_file.2 extattr_list_fd.2 \
 	extattr_get_file.2 extattr_list_file.2 \
 	extattr_get_file.2 extattr_list_link.2 \
 	extattr_get_file.2 extattr_set_fd.2 \
 	extattr_get_file.2 extattr_set_file.2 \
 	extattr_get_file.2 extattr_set_link.2
 MLINKS+=ffclock.2 ffclock_getcounter.2 \
 	ffclock.2 ffclock_getestimate.2 \
 	ffclock.2 ffclock_setestimate.2
 MLINKS+=fhopen.2 fhstat.2 fhopen.2 fhstatfs.2
+MLINKS+=fsync.2 fdatasync.2
 MLINKS+=getdirentries.2 getdents.2
 MLINKS+=getfh.2 lgetfh.2
 MLINKS+=getgid.2 getegid.2
 MLINKS+=getitimer.2 setitimer.2
 MLINKS+=getlogin.2 getlogin_r.3
 MLINKS+=getlogin.2 setlogin.2
 MLINKS+=getloginclass.2 setloginclass.2
 MLINKS+=getpgrp.2 getpgid.2
 MLINKS+=getpid.2 getppid.2
 MLINKS+=getpriority.2 setpriority.2
 MLINKS+=getrlimit.2 setrlimit.2
 MLINKS+=getsockopt.2 setsockopt.2
 MLINKS+=gettimeofday.2 settimeofday.2
 MLINKS+=getuid.2 geteuid.2
 MLINKS+=intro.2 errno.2
 MLINKS+=jail.2 jail_attach.2 \
 	jail.2 jail_get.2 \
 	jail.2 jail_remove.2 \
 	jail.2 jail_set.2
 MLINKS+=kldunload.2 kldunloadf.2
 MLINKS+=kqueue.2 kevent.2 \
 	kqueue.2 EV_SET.3
 MLINKS+=link.2 linkat.2
 MLINKS+=madvise.2 posix_madvise.2
 MLINKS+=mkdir.2 mkdirat.2
 MLINKS+=mkfifo.2 mkfifoat.2
 MLINKS+=mknod.2 mknodat.2
 MLINKS+=mlock.2 munlock.2
 MLINKS+=mlockall.2 munlockall.2
 MLINKS+=modnext.2 modfnext.2
 MLINKS+=mount.2 nmount.2 \
 	mount.2 unmount.2
 MLINKS+=mq_receive.2 mq_timedreceive.2
 MLINKS+=mq_send.2 mq_timedsend.2
 MLINKS+=ntp_adjtime.2 ntp_gettime.2
 MLINKS+=numa_getaffinity.2 numa_setaffinity.2
 MLINKS+=open.2 openat.2
 MLINKS+=pathconf.2 fpathconf.2
 MLINKS+=pathconf.2 lpathconf.2
 MLINKS+=pdfork.2 pdgetpid.2\
 	pdfork.2 pdkill.2 \
 	pdfork.2 pdwait4.2
 MLINKS+=pipe.2 pipe2.2
 MLINKS+=poll.2 ppoll.2
 MLINKS+=read.2 pread.2 \
 	read.2 preadv.2 \
 	read.2 readv.2
 MLINKS+=readlink.2 readlinkat.2
 MLINKS+=recv.2 recvfrom.2 \
 	recv.2 recvmsg.2
 MLINKS+=rename.2 renameat.2
 MLINKS+=rtprio.2 rtprio_thread.2
 .if !defined(NO_P1003_1B)
 MLINKS+=sched_get_priority_max.2 sched_get_priority_min.2 \
 	sched_get_priority_max.2 sched_rr_get_interval.2
 MLINKS+=sched_setparam.2 sched_getparam.2
 MLINKS+=sched_setscheduler.2 sched_getscheduler.2
 .endif
 MLINKS+=select.2 FD_CLR.3 \
 	select.2 FD_ISSET.3 \
 	select.2 FD_SET.3 \
 	select.2 FD_ZERO.3
 MLINKS+=send.2 sendmsg.2 \
 	send.2 sendto.2
 MLINKS+=setpgid.2 setpgrp.2
 MLINKS+=setresuid.2 getresgid.2 \
 	setresuid.2 getresuid.2 \
 	setresuid.2 setresgid.2
 MLINKS+=setuid.2 setegid.2 \
 	setuid.2 seteuid.2 \
 	setuid.2 setgid.2
 MLINKS+=shmat.2 shmdt.2
 MLINKS+=shm_open.2 shm_unlink.2
 MLINKS+=sigwaitinfo.2 sigtimedwait.2
 MLINKS+=stat.2 fstat.2 \
 	stat.2 fstatat.2 \
 	stat.2 lstat.2
 MLINKS+=statfs.2 fstatfs.2
 MLINKS+=swapon.2 swapoff.2
 MLINKS+=symlink.2 symlinkat.2
 MLINKS+=syscall.2 __syscall.2
 MLINKS+=timer_settime.2 timer_getoverrun.2 \
 	timer_settime.2 timer_gettime.2
 MLINKS+=thr_kill.2 thr_kill2.2
 MLINKS+=truncate.2 ftruncate.2
 MLINKS+=unlink.2 unlinkat.2
 MLINKS+=utimensat.2 futimens.2
 MLINKS+=utimes.2 futimes.2 \
 	utimes.2 futimesat.2 \
 	utimes.2 lutimes.2
 MLINKS+=wait.2 wait3.2 \
 	wait.2 wait4.2 \
 	wait.2 waitpid.2 \
 	wait.2 waitid.2 \
 	wait.2 wait6.2
 MLINKS+=write.2 pwrite.2 \
 	write.2 pwritev.2 \
 	write.2 writev.2
Index: head/lib/libc/sys/fsync.2
===================================================================
--- head/lib/libc/sys/fsync.2	(revision 304286)
+++ head/lib/libc/sys/fsync.2	(revision 304287)
@@ -1,87 +1,130 @@
 .\" Copyright (c) 1983, 1993
 .\"	The Regents of the University of California.  All rights reserved.
+.\" Copyright (c) 2016 The FreeBSD Foundation, Inc.
+.\" All rights reserved.
 .\"
+.\" Parts of this documentation were written by
+.\" Konstantin Belousov <kib@FreeBSD.org> under sponsorship
+.\" from the FreeBSD Foundation.
+.\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
 .\" are met:
 .\" 1. Redistributions of source code must retain the above copyright
 .\"    notice, this list of conditions and the following disclaimer.
 .\" 2. Redistributions in binary form must reproduce the above copyright
 .\"    notice, this list of conditions and the following disclaimer in the
 .\"    documentation and/or other materials provided with the distribution.
 .\" 4. Neither the name of the University nor the names of its contributors
 .\"    may be used to endorse or promote products derived from this software
 .\"    without specific prior written permission.
 .\"
 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 .\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
 .\"     @(#)fsync.2	8.1 (Berkeley) 6/4/93
 .\" $FreeBSD$
 .\"
-.Dd June 4, 1993
+.Dd August 17, 2016
 .Dt FSYNC 2
 .Os
 .Sh NAME
-.Nm fsync
+.Nm fdatasync, fsync
 .Nd "synchronise changes to a file"
 .Sh LIBRARY
 .Lb libc
 .Sh SYNOPSIS
 .In unistd.h
 .Ft int
+.Fn fdatasync "int fd"
+.Ft int
 .Fn fsync "int fd"
 .Sh DESCRIPTION
 The
 .Fn fsync
 system call
-causes all modified data and attributes of
+causes all modified data and attributes of the file referenced by
+the file descriptor
 .Fa fd
 to be moved to a permanent storage device.
 This normally results in all in-core modified copies
 of buffers for the associated file to be written to a disk.
 .Pp
 The
+.Fn fdatasync
+system call causes all modified data of
+.Fa fd
+to be moved to a permanent storage device.
+Unlike
+.Fn fsync ,
+the system call does not guarantee that file attributes or
+metadata necessary to access the file are committed to the permanent storage.
+.Pp
+The
 .Fn fsync
 system call
 should be used by programs that require a file to be
 in a known state, for example, in building a simple transaction
 facility.
+If the file metadata has already been committed, using
+.Fn fdatasync
+can be more efficient than
+.Fn fsync .
+.Pp
+Both
+.Fn fdatasync
+and
+.Fn fsync
+calls are cancellation points.
 .Sh RETURN VALUES
 .Rv -std fsync
 .Sh ERRORS
 The
 .Fn fsync
-fails if:
+and
+.Fn fdatasync
+calls fail if:
 .Bl -tag -width Er
 .It Bq Er EBADF
 The
 .Fa fd
 argument
 is not a valid descriptor.
 .It Bq Er EINVAL
 The
 .Fa fd
 argument
 refers to a socket, not to a file.
 .It Bq Er EIO
 An I/O error occurred while reading from or writing to the file system.
 .El
 .Sh SEE ALSO
 .Xr sync 2 ,
 .Xr syncer 4 ,
 .Xr sync 8
 .Sh HISTORY
 The
 .Fn fsync
 system call appeared in
 .Bx 4.2 .
+The
+.Fn fdatasync
+system call appeared in
+.Fx 12.0
+.Sh BUGS
+The
+.Fn fdatasync
+system call currently does not guarantee that enqueued
+.Xr aio 4
+requests for the file referenced by
+.Fa fd
+are completed before the syscall returns.