Commit Graph

1936 Commits

Author SHA1 Message Date
Alan Somers
8d3443b1fc clock_gettime(2): add a HISTORY section
MFC after:	2 weeks
2019-12-07 16:45:12 +00:00
Alan Somers
fbf7102d14 lio_listio(2): add a HISTORY section
MFC after:	2 weeks
2019-12-07 16:29:56 +00:00
Warner Losh
f86e60008b Regularize my copyright notice
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
  All Rights Reserved on same line as other copyright holders (but not
  me). Other such holders are also listed last where it's clear.
2019-12-04 16:56:11 +00:00
Mark Johnston
a6d05b9be7 Fix typos in the cpuset_{get,set}domain() man page.
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2019-11-22 16:25:00 +00:00
Rick Macklem
51e069ac10 Update the copy_file_range man page to reflect the semantic change
done by r354574.

This is a content change.
2019-11-10 01:13:41 +00:00
Rick Macklem
fef163e117 Update the copy_file_range.2 man page to reflect the semantic change
implemented by r354564.

This is a content change.
2019-11-08 23:49:27 +00:00
Kyle Evans
142c5c8c36 memfd_create(3): Don't actually force hugetlb size with MFD_HUGETLB
The size flags are only required to select a size on systems that support
multiple sizes. MFD_HUGETLB by itself is valid.
2019-09-29 17:30:10 +00:00
Warner Losh
ab311b7f12 Revert the mode_t -> int changes and add a warning in the BUGS section instead.
While FreeBSD's implementation of these expect an int inside of libc, that's an
implementation detail that we can hide from the user as it's the natural
promotion of the current mode_t type and before it is used in the kernel, it's
converted back to the narrower type that's the current definition of mode_t. As
such, documenting int is at best confusing and at worst misleading. Instead add
a note that these args are variadic and as such calling conventions may differ
from non-variadic arguments.
2019-09-28 17:15:48 +00:00
Warner Losh
4470d73996 Document varadic args as int, since you can't have short varadic args (they are
promoted to ints).

- `mode_t` is `uint16_t` (`sys/sys/_types.h`)
- `openat` takes variadic args
- variadic args cannot be 16-bit, and indeed the code uses int
- the manpage currently kinda implies the argument is 16-bit by saying `mode_t`

Prompted by Rust things: https://github.com/tailhook/openat/issues/21
Submitted by: Greg V at unrelenting
Differential Revision: https://reviews.freebsd.org/D21816
2019-09-27 16:11:47 +00:00
Kyle Evans
e12ff89136 Further normalize copyright notices
- s/C/c/ where I've been inconsistent about it
- +SPDX tags
- Remove "All rights reserved" where possible

Requested by:	rgrimes (all rights reserved)
2019-09-26 16:19:22 +00:00
David Bright
d4f4430503 Correct mistake in MLINKS introduced in r352747
Messed up a merge conflict resolution and didn't catch that before
commit.

Sponsored by:	Dell EMC Isilon
2019-09-26 16:13:17 +00:00
David Bright
9afb12bab4 Add an shm_rename syscall
Add an atomic shm rename operation, similar in spirit to a file
rename. Atomically unlink an shm from a source path and link it to a
destination path. If an existing shm is linked at the destination
path, unlink it as part of the same atomic operation. The caller needs
the same permissions as shm_unlink to the shm being renamed, and the
same permissions for the shm at the destination which is being
unlinked, if it exists. If those fail, EACCES is returned, as with the
other shm_* syscalls.

truss support is included; audit support will come later.

This commit includes only the implementation; the sysent-generated
bits will come in a follow-on commit.

Submitted by:	Matthew Bryan <matthew.bryan@isilon.com>
Reviewed by:	jilles (earlier revision)
Reviewed by:	brueffer (manpages, earlier revision)
Relnotes:	yes
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D21423
2019-09-26 15:32:28 +00:00
Kyle Evans
a631497fca Add SPDX tags to recently added files
Reported by:	Pawel Biernacki
2019-09-25 22:53:30 +00:00
Kyle Evans
c34a5f16fa posix_spawn(3): handle potential signal issues with vfork
Described in [1], signal handlers running in a vfork child have
opportunities to corrupt the parent's state. Address this by adding a new
rfork(2) flag, RFSPAWN, that has vfork(2) semantics but also resets signal
handlers in the child during creation.

x86 uses rfork_thread(3) instead of a direct rfork(2) because rfork with
RFMEM/RFSPAWN cannot work when the return address is stored on the stack --
further information about this problem is described under RFMEM in the
rfork(2) man page.

Addressing this has been identified as a prerequisite to using posix_spawn
in subprocess on FreeBSD [2].

[1] https://ewontfix.com/7/
[2] https://bugs.python.org/issue35823

Reviewed by:	jilles, kib
Differential Revision:	https://reviews.freebsd.org/D19058
2019-09-25 19:22:03 +00:00
Kyle Evans
079c5b9ed8 rfork(2): add RFSPAWN flag
When RFSPAWN is passed, rfork exhibits vfork(2) semantics but also resets
signal handlers in the child during creation to avoid a point of corruption
of parent state from the child.

This flag will be used by posix_spawn(3) to handle potential signal issues.

Reviewed by:	jilles, kib
Differential Revision:	https://reviews.freebsd.org/D19058
2019-09-25 19:20:41 +00:00
Kyle Evans
a9ac5e1424 sysent: regenerate after r352705
This also implements it, fixes kdump, and removes no longer needed bits from
lib/libc/sys/shm_open.c for the interim.
2019-09-25 18:09:19 +00:00
Kyle Evans
3e25d1fb61 Add linux-compatible memfd_create
memfd_create is effectively a SHM_ANON shm_open(2) mapping with optional
CLOEXEC and file sealing support. This is used by some mesa parts, some
linux libs, and qemu can also take advantage of it and uses the sealing to
prevent resizing the region.

This reimplements shm_open in terms of shm_open2(2) at the same time.

shm_open(2) will be moved to COMPAT12 shortly.

Reviewed by:	markj, kib
Differential Revision:	https://reviews.freebsd.org/D21393
2019-09-25 18:03:18 +00:00
Kyle Evans
f17221ee7a Update fcntl(2) after r352695 2019-09-25 17:33:12 +00:00
Sean Eric Fagan
ba7a55d934 Add two options to allow mount to avoid covering up existing mount points.
The two options are

* nocover/cover:  Prevent/allow mounting over an existing root mountpoint.
E.g., "mount -t ufs -o nocover /dev/sd1a /usr/local" will fail if /usr/local
is already a mountpoint.
* emptydir/noemptydir:  Prevent/allow mounting on a non-empty directory.
E.g., "mount -t ufs -o emptydir /dev/sd1a /usr" will fail.

Neither of these options is intended to be a default, for historical and
compatibility reasons.

Reviewed by:	allanjude, kib
Differential Revision:	https://reviews.freebsd.org/D21458
2019-09-23 04:28:07 +00:00
Konstantin Belousov
55894117b1 Return EISDIR when directory is opened with O_CREAT without O_DIRECTORY.
Reviewed by:	bcr (man page), emaste (previous version)
PR:	240452
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
DIfferential revision:	https://reviews.freebsd.org/D21634
2019-09-17 18:32:18 +00:00
Alan Somers
8d910a4282 getsockopt.2: clarify that SO_TIMESTAMP is not 100% reliable
When SO_TIMESTAMP is set, the kernel will attempt to attach a timestamp as
ancillary data to each IP datagram that is received on the socket. However,
it may fail, for example due to insufficient memory. In that case the
packet will still be received but not timestamp will be attached.

Reviewed by:	kib
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D21607
2019-09-11 19:48:32 +00:00
Mitchell Horne
d1bc2d79f2 Fix cpuwhich_t column width
Not bumping .Dd since this is purely a format change.

Approved by:	markj (mentor)
2019-09-08 21:37:52 +00:00
Konstantin Belousov
fe69291ff4 Add procctl(PROC_STACKGAP_CTL)
It allows a process to request that stack gap was not applied to its
stacks, retroactively.  Also it is possible to control the gaps in the
process after exec.

PR:	239894
Reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D21352
2019-09-03 18:56:25 +00:00
Mateusz Guzik
d05b53e0ba Add sysctlbyname system call
Previously userspace would issue one syscall to resolve the sysctl and then
another one to actually use it. Do it all in one trip.

Fallback is provided in case newer libc happens to be running on an older
kernel.

Submitted by:	Pawel Biernacki
Reported by:	kib, brooks
Differential Revision:	https://reviews.freebsd.org/D17282
2019-09-03 04:16:30 +00:00
Ed Maste
3afdc7303c Add @generated tag to libc syscall asm wrappers
Although libc syscall wrappers do not get checked in this can aid in
finding the source of generated files when spelunking in the objdir.

Multiple tools use @generated to identify generated files (for example,
in a review Phabricator will by default hide diffs in generated files).
For consistency use the @generated tag in makesyscalls.sh as we've done
for other generated files, even though these wrappers aren't checked in
to the tree.
2019-08-16 14:14:57 +00:00
Konstantin Belousov
a60c863ced wait(2): clarify reparenting of children of the exiting process.
Point to the existence of reapers and mention that init is the default
reaper.

Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2019-08-11 15:47:48 +00:00
Konstantin Belousov
cd6a6b772d wait(2): split long line by using .Fo/.Fa instead of .Ft.
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2019-08-11 15:44:36 +00:00
Benjamin Kaduk
1f0a85545e Fix grammar nit in copy_file_range docs
Bytes are countable, so we have fewer of them, not less of them.
2019-07-25 15:43:15 +00:00
Rick Macklem
78756b9e6f Add libc support for the copy_file_range(2) syscall added by r350315.
copy_file_range.2 is a new man page (content change).

Reviewed by:	kib, asomers
Relnotes:	yes
Differential Revision:	https://reviews.freebsd.org/D20584
2019-07-25 06:05:49 +00:00
John Baldwin
32451fb9fc Add ptrace op PT_GET_SC_RET.
This ptrace operation returns a structure containing the error and
return values from the current system call.  It is only valid when a
thread is stopped during a system call exit (PL_FLAG_SCX is set).

The sr_error member holds the error value from the system call.  Note
that this error value is the native FreeBSD error value that has _not_
been translated to an ABI-specific error value similar to the values
logged to ktrace.

If sr_error is zero, then the return values of the system call will be
set in sr_retval[0] and sr_retval[1].

Reviewed by:	kib
MFC after:	1 month
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D20901
2019-07-15 21:48:02 +00:00
Konstantin Belousov
8c95181495 Document atomicity for read(2) and write(2).
Take part of the text from POSIX 2018 edition and describe the
atomicity requirements for read and write syscalls.  See p1003.1-2018,
Vol.2, 2.9.7 Threads interaction with Regular File Operations.

Reviewed by:	asomers
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
Differential revision:	https://reviews.freebsd.org/D20867
2019-07-06 20:31:37 +00:00
Konstantin Belousov
5dc7e31a09 Control implicit PROT_MAX() using procctl(2) and the FreeBSD note
feature bit.

In particular, allocate the bit to opt-out the image from implicit
PROTMAX enablement.  Provide procctl(2) verbs to set and query
implicit PROTMAX handling.  The knobs mimic the same per-image flag
and per-process controls for ASLR.

Reviewed by:	emaste, markj (previous version)
Discussed with:	brooks
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D20795
2019-07-02 19:07:17 +00:00
Konstantin Belousov
e0a126f6d2 Typo.
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2019-06-28 16:42:44 +00:00
Brooks Davis
ee37749af6 Add PROT_MAX to the HISTORY section.
In the case of mmap(), add a HISTORY section.  Mention that mmap() and
mprotect()'s documentation predates an implementation.  The
implementation first saw wide use in 4.3-Reno, but there seems to be no
easy way to express that in mdoc so stick with 4.4BSD.

Reviewed by:	emaste
Requested by:	cem
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D20713
2019-06-20 21:52:30 +00:00
Brooks Davis
74a1b66cf4 Extend mmap/mprotect API to specify the max page protections.
A new macro PROT_MAX() alters a protection value so it can be OR'd with
a regular protection value to specify the maximum permissions.  If
present, these flags specify the maximum permissions.

While these flags are non-portable, they can be used in portable code
with simple ifdefs to expand PROT_MAX() to 0.

This change allows (e.g.) a region that must be writable during run-time
linking or JIT code generation to be made permanently read+execute after
writes are complete.  This complements W^X protections allowing more
precise control by the programmer.

This change alters mprotect argument checking and returns an error when
unhandled protection flags are set.  This differs from POSIX (in that
POSIX only specifies an error), but is the documented behavior on Linux
and more closely matches historical mmap behavior.

In addition to explicit setting of the maximum permissions, an
experimental sysctl vm.imply_prot_max causes mmap to assume that the
initial permissions requested should be the maximum when the sysctl is
set to 1.  PROT_NONE mappings are excluded from this for compatibility
with rtld and other consumers that use such mappings to reserve
address space before mapping contents into part of the reservation.  A
final version this is expected to provide per-binary and per-process
opt-in/out options and this sysctl will go away in its current form.
As such it is undocumented.

Reviewed by:	emaste, kib (prior version), markj
Additional suggestions from:	alc
Obtained from:	CheriBSD
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D18880
2019-06-20 18:24:16 +00:00
Alan Somers
5993fa5582 open(2): fix the description of O_FSYNC
The man page claims that with O_FSYNC (aka O_SYNC) the kernel will not cache
written data. However, that's not true. Nor does POSIX require it.
Perhaps it was true when that section of the man page was written in r69336
(I haven't checked). But it's not true now.  Now the effect is simply that
writes are sent to disk immediately and synchronously, but they're still
cached.

See also: https://pubs.opengroup.org/onlinepubs/9699919799/
See also: ffs_write in sys/ufs/ffs/ffs_vnops.c

Reviewed by:	cem
MFC after:	2 weeks
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20641
2019-06-14 20:35:37 +00:00
Mariusz Zaborski
5c816e43b4 unlink: add missing function to unlink.2 man page 2019-06-05 22:36:19 +00:00
Alan Somers
8bbd9a3839 Link fhlinkat(2) man page
Reviewed by:	kib
MFC after:	3 days
MFC-With:	r341689
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20339
2019-05-22 01:11:21 +00:00
Mark Johnston
54a3a11421 Provide separate accounting for user-wired pages.
Historically we have not distinguished between kernel wirings and user
wirings for accounting purposes.  User wirings (via mlock(2)) were
subject to a global limit on the number of wired pages, so if large
swaths of physical memory were wired by the kernel, as happens with
the ZFS ARC among other things, the limit could be exceeded, causing
user wirings to fail.

The change adds a new counter, v_user_wire_count, which counts the
number of virtual pages wired by user processes via mlock(2) and
mlockall(2).  Only user-wired pages are subject to the system-wide
limit which helps provide some safety against deadlocks.  In
particular, while sources of kernel wirings typically support some
backpressure mechanism, there is no way to reclaim user-wired pages
shorting of killing the wiring process.  The limit is exported as
vm.max_user_wired, renamed from vm.max_wired, and changed from u_int
to u_long.

The choice to count virtual user-wired pages rather than physical
pages was done for simplicity.  There are mechanisms that can cause
user-wired mappings to be destroyed while maintaining a wiring of
the backing physical page; these make it difficult to accurately
track user wirings at the physical page layer.

The change also closes some holes which allowed user wirings to succeed
even when they would cause the system limit to be exceeded.  For
instance, mmap() may now fail with ENOMEM in a process that has called
mlockall(MCL_FUTURE) if the new mapping would cause the user wiring
limit to be exceeded.

Note that bhyve -S is subject to the user wiring limit, which defaults
to 1/3 of physical RAM.  Users that wish to exceed the limit must tune
vm.max_user_wired.

Reviewed by:	kib, ngie (mlock() test changes)
Tested by:	pho (earlier version)
MFC after:	45 days
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D19908
2019-05-13 16:38:48 +00:00
Edward Tomasz Napierala
9b7448fcad .Xr protect(1) and proccontrol(1) from procctl(2).
MFC after:	2 weeks
Sponsored by:	DARPA, AFRL
2019-04-09 10:09:59 +00:00
Mariusz Zaborski
a1304030b8 Introduce funlinkat syscall that always us to check if we are removing
the file associated with the given file descriptor.

Reviewed by:	kib, asomers
Reviewed by:	cem, jilles, brooks (they reviewed previous version)
Discussed with:	pjd, and many others
Differential Revision:	https://reviews.freebsd.org/D14567
2019-04-06 09:34:26 +00:00
Konstantin Belousov
5d00c5a657 Fix initial exec TLS mode for dynamically loaded shared objects.
If dso uses initial exec TLS mode, rtld tries to allocate TLS in
static space. If there is no space left, the dlopen(3) fails. If space
if allocated, initial content from PT_TLS segment is distributed to
all threads' pcbs, which was missed and caused un-initialized TLS
segment for such dso after dlopen(3).

The mode is auto-detected either due to the relocation used, or if the
DF_STATIC_TLS dynamic flag is set.  In the later case, the TLS segment
is tried to allocate earlier, which increases chance of the dlopen(3)
to succeed.  LLD was recently fixed to properly emit the flag, ld.bdf
did it always.

Initial test by:	dumbbell
Tested by:	emaste (amd64), ian (arm)
Tested by:	Gerald Aryeetey <aryeeteygerald_rogers.com> (arm64)
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D19072
2019-03-29 17:52:57 +00:00
Ed Maste
f6a10ccc53 Use consistent struct stat arg name in stat man page
stat, lstat, and fstat use `*sb` as the stat struct pointer arg name,
while fstatat previously used `*buf`.

MFC after:	1 week
2019-03-13 15:18:14 +00:00
Ed Maste
d95826c43d poll.2: POLLNVAL is returned also for insufficient rights
Reported by:	"Bora Özarslan" <borako.ozarslan@gmail.com>
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2019-02-27 17:52:22 +00:00
Konstantin Belousov
9fb91a0a7d procctl(2): document ASLR knobs.
Reviewed by:	0mp
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D19308
2019-02-26 17:41:41 +00:00
Konstantin Belousov
80a3fa4893 procctl(2): fix -width parameter to .Bl.
According to 0mp, macros are not expanded in the argument provided to
-width.  Use plain identifiers for width specification.

Noted and reviewed by:	0mp
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
Differential revision:	https://reviews.freebsd.org/D19308
2019-02-26 17:35:06 +00:00
Gleb Smirnoff
5bfb2e008d Imaginary cat jumped my keyboard! 2019-02-15 23:46:34 +00:00
Gleb Smirnoff
66fb0b1ad7 For 32-bit machines rollback the default number of vnode pager pbufs
back to the lever before r343030.  For 64-bit machines reduce it slightly,
too.  Together with r343030 I bumped the limit up to the value we use at
Netflix to serve 100 Gbit/s of sendfile traffic, and it probably isn't a
good default.

Provide a loader tunable to change vnode pager pbufs count. Document it.
2019-02-15 23:36:22 +00:00
Sergey Kandaurov
78c8b9477c Document the ENOBUFS errno in setsockopt(2).
In particular, it is the case if SO_SNDBUF/SO_RCVBUF would exceed sb_max_adj.

PR:		200649
MFC after:	1 week
2019-02-09 21:33:32 +00:00
Enji Cooper
2b9ecf4896 Document that sendfile will return an invalid value for sbytes if provided an invalid address
This is meant to clarify the fact that the system call will not fail
with -1/EFAULT, as one might expect, when reading the sendfile(2)
manpage today.

While here, pet the mandoc linter, when dealing with the section that
describes valid values for `flags`.

PR:	232210
MFC after:	2 weeks
Approved by:	emaste (mentor)
Reviewed by:	glebius, 0mp
Differential Revision: https://reviews.freebsd.org/D18949
2019-01-25 19:56:02 +00:00
Kirk McKusick
88640c0e8b Create new EINTEGRITY error with message "Integrity check failed".
An integrity check such as a check-hash or a cross-correlation failed.
The integrity error falls between EINVAL that identifies errors in
parameters to a system call and EIO that identifies errors with the
underlying storage media. EINTEGRITY is typically raised by intermediate
kernel layers such as a filesystem or an in-kernel GEOM subsystem when
they detect inconsistencies. Uses include allowing the mount(8) command
to return a different exit value to automate the running of fsck(8)
during a system boot.

These changes make no use of the new error, they just add it. Later
commits will be made for the use of the new error number and it will
be added to additional manual pages as appropriate.

Reviewed by:    gnn, dim, brueffer, imp
Discussed with: kib, cem, emaste, ed, jilles
Differential Revision: https://reviews.freebsd.org/D18765
2019-01-17 06:35:45 +00:00
Konstantin Belousov
ea7e7006db Implement shmat(2) flag SHM_REMAP.
Based on the description in Linux man page.

Reviewed by:	markj, ngie (previous version)
Sponsored by:	Mellanox Technologies
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D18837
2019-01-16 05:15:57 +00:00
Konstantin Belousov
3fbc2e00d1 Add a tunable which changes mincore(2) algorithm to only report data
from the local mapping.

Enable the setting by default.
The article behind the change: https://arxiv.org/abs/1901.01161

Reviewed by:	markj
Discussed with:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D18764
2019-01-07 22:10:48 +00:00
Jilles Tjoelker
8cc4b29d5a thr_wake(2): Minor mdoc fixes
MFC after:	1 week
2019-01-06 21:34:05 +00:00
Mark Johnston
2f2ddd68a5 Support MSG_DONTWAIT in send*(2).
As it does for recv*(2), MSG_DONTWAIT indicates that the call should
not block, returning EAGAIN instead.  Linux and OpenBSD both implement
this, so the change makes porting easier, especially since we do not
return EINVAL or so when unrecognized flags are specified.

Submitted by:	Greg V <greg@unrelenting.technology>
Reviewed by:	tuexen
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D18728
2019-01-04 17:31:50 +00:00
Konstantin Belousov
eba8ab0e3e Remove special case handling for getfhat(fd, NULL, handle).
There is no reason for it to behave differently from openat(fd, NULL).
Also the handling did not worked because the substituted path was from
the system address space, causing EFAULT.

Submitted by:	Jack Halford <jack@gandi.net>
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D18501
2018-12-11 02:48:49 +00:00
Konstantin Belousov
d1fd400a80 Add new file handle system calls.
Namely, getfhat(2), fhlink(2), fhlinkat(2), fhreadlink(2).  The
syscalls are provided for a NFS userspace server (nfs-ganesha).

Submitted by:	Jack Halford <jack@gandi.net>
Sponsored by:	Gandi.net
Tested by:	pho
Feedback from:	brooks, markj
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D18359
2018-12-07 15:17:29 +00:00
Alan Somers
006678fd05 stat(2): clarify which syscalls modify file timestamps
The list of syscalls that modify st_atim, st_mtim, and st_ctim was quite out
of date and probably not accurate to begin with.  Update it, and make it
clear that the list is open-ended.

Reviewed by:	kib
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D18410
2018-12-05 17:28:40 +00:00
Alan Somers
a14a34ef62 fcntl.2: document an additional error condition
MFC after:	2 weeks
2018-11-15 16:13:25 +00:00
Konstantin Belousov
1c4ca77890 Add d_off support for multiple filesystems.
The d_off field has been added to the dirent structure recently.
Currently filesystems don't support this feature.  Support has been
added and tested for zfs, ufs, ext2fs, fdescfs, msdosfs and unionfs.
A stub implementation is available for cd9660, nandfs, udf and
pseudofs but hasn't been tested.

Motivation for this feature: our usecase is for a userspace nfs server
(nfs-ganesha) with zfs.  At the moment we cache direntry offsets by
calling lseek once per entry, with this patch we can get the offset
directly from getdirentries(2) calls which provides a significant
speedup.

Submitted by:	Jack Halford <jack@gandi.net>
Reviewed by:	mckusick, pfg, rmacklem (previous versions)
Sponsored by:	Gandi.net
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D17917
2018-11-14 14:18:35 +00:00
Konstantin Belousov
5b1fb8ec66 First draft of documentation for AT/O_BENEATH handling of the absolute
paths.

It was decided that committing the code and drafting of the man page
update is better than allowing the code to rot until wordsmithing
happens.

Reviewed by:	jilles (previous version)
Discussed with:	brooks, jilles, emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D17714
2018-11-11 01:46:48 +00:00
Conrad Meyer
78c2a9806e kern_poll: Restore explanatory comment removed in r177374
The comment isn't stale.  The check is bogus in the sense that poll(2)
does not require pollfd entries to be unique in fd space, so there is no
reason there cannot be more pollfd entries than open or even allowed
fds.  The check is mostly a seatbelt against accidental misuse or
abuse.  FD_SETSIZE, while usually unrelated to poll, is used as an
arbitrary floor for systems with very low kern.maxfilesperproc.

Additionally, document this possible EINVAL condition in the poll.2
manual.

No functional change.

Reviewed by:	markj
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D17671
2018-11-01 23:46:23 +00:00
Warner Losh
f64bccc6d9 Bump .Dd forgotten in last commit. 2018-10-28 03:02:09 +00:00
Warner Losh
5669c6748d Note that the kenrel doesn't keep track daylight savings time, nor
timezone offset. These values are generally zero.

While one still theoreticall could set these values, that's almost
never done. Users wishing to have an offset between the time of day
clock hardware and UTC use adjkerntz(8) instead.

localtime(3) should be used to find these values for the current
timezone.
2018-10-28 02:58:22 +00:00
Konstantin Belousov
4f77f48884 Implement O_BENEATH and AT_BENEATH.
Flags prevent open(2) and *at(2) vfs syscalls name lookup from
escaping the starting directory.  Supposedly the interface is similar
to the same proposed Linux flags.

Reviewed by:	jilles (code, previous version of manpages), 0mp (manpages)
Discussed with:	allanjude, emaste, jonathan
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D17547
2018-10-25 22:16:34 +00:00
Mark Johnston
b8e4cdda35 Clarify slightly the interaction between wait*() and pdfork().
There are multiple ways to wait for any child process to return a
status (e.g., waitpid(-1, ...), waitid(P_ALL, ...)), so don't be so
specific.

MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
2018-10-24 18:42:13 +00:00
Poul-Henning Kamp
01652e9c8e Update example to something people less than 40 years old have heard about. 2018-10-21 07:30:26 +00:00
Edward Tomasz Napierala
edbedaf4dc Add .Xrs to kqueue(2) from pdfork(2) and procdesc(4), to make EVFILT_PROCDESC
easier to find.

Approved by:	re (rgrimes)
MFC after:	2 weeks
Sponsored by:	DARPA, AFRL
2018-10-14 18:42:54 +00:00
Allan Jude
c452913091 Document that sendfile(2) can return ENOTCAPABLE
PR:		232207
Submitted by:	Enji Cooper <yaneurabeya@gmail.com>
Approved by:	re (rgrimes)
2018-10-13 02:20:16 +00:00
Michael Tuexen
6b01d4d433 Add SOL_SOCKET level socket option with name SO_DOMAIN to get
the domain of a socket.

This is helpful when testing and Solaris and Linux have the same
socket option using the same name.

Reviewed by:		bcr@, rrs@
Sponsored by:		Netflix, Inc.
Differential Revision:	https://reviews.freebsd.org/D16791
2018-08-21 14:04:30 +00:00
Mateusz Piotrowski
c8b8b38e5f Document socket control message routines for ancillary data access (CMSG_DATA).
PR:		227777
Reviewed by:	bcr, eadler
Approved by:	mat (mentor), manpages (bcr)
Obtained from:	OpenBSD
Differential Revision:	https://reviews.freebsd.org/D15215
2018-08-19 17:42:49 +00:00
Jamie Gritton
c542c43ef1 Revert r337922, except for some documention-only bits. This needs to wait
until user is changed to stop using jail(2).

Differential Revision:	D14791
2018-08-16 19:09:43 +00:00
Jamie Gritton
284001a222 Put jail(2) under COMPAT_FREEBSD11. It has been the "old" way of creating
jails since FreeBSD 7.

Along with the system call, put the various security.jail.allow_foo and
security.jail.foo_allowed sysctls partly under COMPAT_FREEBSD11 (or
BURN_BRIDGES).  These sysctls had two disparate uses: on the system side,
they were global permissions for jails created via jail(2) which lacked
fine-grained permission controls; inside a jail, they're read-only
descriptions of what the current jail is allowed to do.  The first use
is obsolete along with jail(2), but keep them for the second-read-only use.

Differential Revision:	D14791
2018-08-16 18:40:16 +00:00
Conrad Meyer
ba9ace7436 settimeofday(2): Remove stale note about timezone
Contrary to the removed comment, the kernel does appear to use the timezone
argument of settimeofday.  The comment dates to the BSD4.4 import; I assume it
is just stale.
2018-08-04 22:08:24 +00:00
Ruslan Bukin
42570cd1d4 MAXLOGNAME changed to 33 in r243023.
Update man pages.

Sponsored by:	DARPA, AFRL
2018-08-03 16:05:03 +00:00
David Bright
95c05062ec Allow a EVFILT_TIMER kevent to be updated.
If a timer is updated (re-added) with a different time period
(specified in the .data field of the kevent), the new time period has
no effect; the timer will not expire until the original time has
elapsed. This violates the documented behavior as the kqueue(2) man
page says (in part) "Re-adding an existing event will modify the
parameters of the original event, and not result in a duplicate
entry."

This modification, adapted from a patch submitted by cem@ to PR214987,
fixes the kqueue system to allow updating a timer entry. The
kevent timer behavior is changed to:

  * When a timer is re-added, update the timer parameters to and
    re-start the timer using the new parameters.
  * Allow updating both active and already expired timers.
  * When the timer has already expired, dequeue any undelivered events
    and clear the count of expirations.

All of these changes address the original PR and also bring the
FreeBSD and macOS kevent timer behaviors into agreement.

A few other changes were made along the way:

  * Update the kqueue(2) man page to reflect the new timer behavior.
  * Fix man page style issues in kqueue(2) diagnosed by igor.
  * Update the timer libkqueue system test to test for the updated
    timer behavior.
  * Fix the (test) libkqueue common.h file so that it includes
    config.h which defines various HAVE_* feature defines, before the
    #if tests for such variables in common.h. This enables the use of
    the actual err(3) family of functions.
  * Fix the usages of the err(3) functions in the tests for incorrect
    type of variables. Those were formerly undiagnosed due to the
    disablement of the err(3) functions (see previous bullet point).

PR:		214987
Reported by:	Brian Wellington <bwelling@xbill.org>
Reviewed by:	kib
MFC after:	1 week
Relnotes:	yes
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D15778
2018-07-27 13:49:17 +00:00
Konstantin Belousov
b3042426d0 Remove bits of the old NUMA.
Remove numactl(1), edit numa(4) to bring it some closer to reality,
provide libc ABI shims for old NUMA syscalls.

Noted and reviewed by:	brooks (previous version)
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D16142
2018-07-10 22:00:20 +00:00
Brooks Davis
7cc923f8a8 Get rid of netbsd_lchown and netbsd_msync syscall entries.
No valid FreeBSD binary very called them (they would call lchown and
msync directly) and we haven't supported NetBSD binaries in ages.

This is a respin of r335983 with a workaround for the ancient BFD linker
in the libc stubs.

Reviewed by:	kib
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D16193
2018-07-10 13:32:04 +00:00
Warner Losh
bdea3adca6 Tweak documentation to RB_ constants to reflect current use
RB_ASKNAME is no longer instructions to the boot loader to request a
prompt for which kernel to boot. Instead, it asks for what the root
file system to use. RB_INITNAME is unused, and never has been in
FreeBSD as far as I can tell. Remove it from the documentation and fix
comment. RB_SELFTEST and RB_MINIROOT likewise (though they were
completely undocumented). These last three constants can likely just
be deleted as nothing references them (even to set useless bits).

RB_ASKNAME doesn't actually survive reboot, however, so needs to be
communicated to the bootloader via other means. If the bootloader sets
it, though, it will be honored.
2018-07-10 00:01:14 +00:00
Brooks Davis
714c03c81e Revert r335983.
The bfd linker in tree doesn't support multiple names for the same
symbol (at least with current flags).
2018-07-05 16:03:03 +00:00
Brooks Davis
5b04a71dae Get rid of netbsd_lchown and netbsd_msync syscall entries.
No valid FreeBSD binary ever called them (they would call lchown and
msync directly) and we haven't supported NetBSD binaries in ages.

Reviewed by:	kib
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D15814
2018-07-05 14:12:56 +00:00
Conrad Meyer
e02d32f72e sigaction.2: Minor cleanups
Add vertical space between struct definition and function prototype.

Use "NULL" to describe zero pointers, instead of "zero."

Remove perhaps unclear "can not" and replace.  Tag struct member names used
with appropriate tags.
2018-06-28 18:17:20 +00:00
Ian Lepore
25b10ed4b7 Add some words clarifying that rename(2) does nothing when the 'from' and
'to' args are the same file.  Wording borrowed from POSIX.1-2017, but
the freebsd code to implement this behavior was added in 2002 (r103180).
2018-06-21 15:21:17 +00:00
Sean Bruno
1a43cff92a Load balance sockets with new SO_REUSEPORT_LB option.
This patch adds a new socket option, SO_REUSEPORT_LB, which allow multiple
programs or threads to bind to the same port and incoming connections will be
load balanced using a hash function.

Most of the code was copied from a similar patch for DragonflyBSD.

However, in DragonflyBSD, load balancing is a global on/off setting and can not
be set per socket. This patch allows for simultaneous use of both the current
SO_REUSEPORT and the new SO_REUSEPORT_LB options on the same system.

Required changes to structures:
Globally change so_options from 16 to 32 bit value to allow for more options.
Add hashtable in pcbinfo to hold all SO_REUSEPORT_LB sockets.

Limitations:
As DragonflyBSD, a load balance group is limited to 256 pcbs (256 programs or
threads sharing the same socket).

This is a substantially different contribution as compared to its original
incarnation at svn r332894 and reverted at svn r332967.  Thanks to rwatson@
for the substantive feedback that is included in this commit.

Submitted by:	Johannes Lundberg <johalun0@gmail.com>
Obtained from:	DragonflyBSD
Relnotes:	Yes
Sponsored by:	Limelight Networks
Differential Revision:	https://reviews.freebsd.org/D11003
2018-06-06 15:45:57 +00:00
Mark Johnston
9f9c9b22ec Reimplement brk() and sbrk() to avoid the use of _end.
Previously, libc.so would initialize its notion of the break address
using _end, a special symbol emitted by the static linker following
the bss section.  Compatibility issues between lld and ld.bfd could
cause the wrong definition of _end (libc.so's definition rather than
that of the executable) to be used, breaking the brk()/sbrk()
interface.

Avoid this problem and future interoperability issues by simply not
relying on _end.  Instead, modify the break() system call to return
the kernel's view of the current break address, and have libc
initialize its state using an extra syscall upon the first use of the
interface.  As a side effect, this appears to fix brk()/sbrk() usage
in executables run with rtld direct exec, since the kernel and libc.so
no longer maintain separate views of the process' break address.

PR:		228574
Reviewed by:	kib (previous version)
MFC after:	2 months
Differential Revision:	https://reviews.freebsd.org/D15663
2018-06-04 19:35:15 +00:00
Justin Hibbits
2e65567500 Added ptrace support for reading/writing powerpc VSX registers
Summary:
Added ptrace support for getting/setting the remaining part of the VSX registers
(the part that's not already covered by FPR or VR registers).

This is necessary to add support for VSX registers in debuggers.

Submitted by:	Luis Pires
Differential Revision: https://reviews.freebsd.org/D15458
2018-06-02 19:17:11 +00:00
Mark Johnston
e2c1730299 Remove an inaccuracy from mincore.2.
Super pages are supported on non-x86 architectures, so just remove the
incorrect note.  While here, change terminology to be consistent with
mmap.2.

MFC after:	1 week
2018-06-01 23:40:43 +00:00
Brooks Davis
7351a8bdb5 Make vadvise compat freebsd11.
The vadvise syscall (aka ovadvise) is undocumented and has always been
implmented as returning EINVAL.  Put the syscall under COMPAT11 and
provide a userspace implementation.

Reviewed by:	kib
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D15557
2018-05-25 20:40:23 +00:00
Brooks Davis
2357535254 Indicate the brk/sbrk are deprecated and not portable.
More firmly suggest mmap(2) instead.

Include the history of arm64 and riscv shipping without brk/sbrk.

Mention that sbrk(0) produces unreliable results.

Reviewed by:	emaste, Marcin Cieślak
MFC after:	3 days
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D15535
2018-05-24 18:32:54 +00:00
Konstantin Belousov
84ffdd6a81 Note that PT_SETSTEP is auto-cleared.
Wording and reviewed by:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
Differential revision:	https://reviews.freebsd.org/D15054
2018-05-23 17:55:30 +00:00
Sevan Janiyan
d3fff23be8 Use St macro for specifying C standards.
Reported by:	rgrimes@
2018-05-20 21:56:08 +00:00
Sevan Janiyan
d55b77df03 Fix a typo and remove an unneeded Tn macro as highlighted by mandoc -Tlint.
Submitted by:		Mateusz Piotrowski
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D15204
2018-05-20 20:28:17 +00:00
Lawrence Stewart
9891578a40 Plug a memory leak and potential NULL-pointer dereference introduced in r331214.
Each TCP connection that uses the system default cc_newreno(4) congestion
control algorithm module leaks a "struct newreno" (8 bytes of memory) at
connection initialisation time. The NULL-pointer dereference is only germane
when using the ABE feature, which is disabled by default.

While at it:

- Defer the allocation of memory until it is actually needed given that ABE is
  optional and disabled by default.

- Document the ENOMEM errno in getsockopt(2)/setsockopt(2).

- Document ENOMEM and ENOBUFS in tcp(4) as being synonymous given that they are
  used interchangeably throughout the code.

- Fix a few other nits also accidentally omitted from the original patch.

Reported by:	Harsh Jain on freebsd-net@
Tested by:	tjh@
Differential Revision:	https://reviews.freebsd.org/D15358
2018-05-17 02:46:27 +00:00
Konstantin Belousov
450cd8475a PROC_PDEATHSIG_CTL will appear first in 11.2.
Submitted by:	Thomas Munro
MFC after:	3 days
Differential revision:	https://reviews.freebsd.org/D15399
2018-05-12 10:11:33 +00:00
Xin LI
b6f7731dba Remove "All rights reserved" from my files.
See r333391 for the rationale.

MFC after:	1 week
2018-05-10 06:41:08 +00:00
Eric van Gyzen
488ab515d6 Remove 'All rights reserved' from my files
See r333391 for the rationale.

Approved by:	emaste (for the Foundation copyright)
Sponsored by:	Dell EMC
2018-05-09 20:12:59 +00:00
Kyle Evans
1921252001 fcntl(2): Vaguely document that ENOTTY is possible, with light examples
Reported by:	vs (2006, FreeBSD 6.1-BETA3)
Reported by:	me (2018, angry debugging session)
MFC after:	1 month
2018-05-03 02:42:13 +00:00
Ed Maste
e2811155f1 Clarify bindat/connectat use with AT_FDCWD
Discovered during investigation into the PR - the description of
AT_FDCWD was somewhat confusing.

PR:		222632
Submitted by:	Jan Kokemüller <jan.kokemueller@gmail.com>
MFC after:	1 week
2018-04-30 17:16:17 +00:00
Konstantin Belousov
1302eea7bb Rename PROC_PDEATHSIG_SET -> PROC_PDEATHSIG_CTL and PROC_PDEATHSIG_GET
-> PROC_PDEATHSIG_STATUS for consistency with other procctl(2)
operations names.

Requested by:	emaste
Sponsored by:	The FreeBSD Foundation
MFC after:	13 days
2018-04-20 15:19:27 +00:00
Konstantin Belousov
b940886338 Add PROC_PDEATHSIG_SET to procctl interface.
Allow processes to request the delivery of a signal upon death of
their parent process.  Supposed consumer of the feature is PostgreSQL.

Submitted by:	Thomas Munro
Reviewed by:	jilles, mjg
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D15106
2018-04-18 21:31:13 +00:00