Commit graph

221 commits

Author SHA1 Message Date
Kyle Evans
7d03e08112 Mark closefrom(2) COMPAT12, reimplement in libc to wrap close_range
Include a temporarily compatibility shim as well for kernels predating
close_range, since closefrom is used in some critical areas.

Reviewed by:	markj (previous version), kib
Differential Revision:	https://reviews.freebsd.org/D24399
2020-04-14 18:07:42 +00:00
Kyle Evans
472ced39ef Implement a close_range(2) syscall
close_range(min, max, flags) allows for a range of descriptors to be
closed. The Python folk have indicated that they would much prefer this
interface to closefrom(2), as the case may be that they/someone have special
fds dup'd to higher in the range and they can't necessarily closefrom(min)
because they don't want to hit the upper range, but relocating them to lower
isn't necessarily feasible.

sys_closefrom has been rewritten to use kern_close_range() using ~0U to
indicate closing to the end of the range. This was chosen rather than
requiring callers of kern_close_range() to hold FILEDESC_SLOCK across the
call to kern_close_range for simplicity.

The flags argument of close_range(2) is currently unused, so any flags set
is currently EINVAL. It was added to the interface in Linux so that future
flags could be added for, e.g., "halt on first error" and things of this
nature.

This patch is based on a syscall of the same design that is expected to be
merged into Linux.

Reviewed by:	kib, markj, vangyzen (all slightly earlier revisions)
Differential Revision:	https://reviews.freebsd.org/D21627
2020-04-12 21:23:19 +00:00
Warner Losh
a5b6c2960d Remove sparc64 specific parts of libc.
Also update comments for which architectures use 128 bit long doubles,
as appropriate.

The softfloat specialization routines weren't updated since they
appear to be from an upstream source which we may want to update in
the future to get a more favorable license.

Reviewed by: emaste@
Differential Revision:  https://reviews.freebsd.org/D23658
2020-02-26 18:55:09 +00:00
Konstantin Belousov
146fc63fce Add a way to manage thread signal mask using shared word, instead of syscall.
A new syscall sigfastblock(2) is added which registers a uint32_t
variable as containing the count of blocks for signal delivery.  Its
content is read by kernel on each syscall entry and on AST processing,
non-zero count of blocks is interpreted same as the signal mask
blocking all signals.

The biggest downside of the feature that I see is that memory
corruption that affects the registered fast sigblock location, would
cause quite strange application misbehavior. For instance, the process
would be immune to ^C (but killable by SIGKILL).

With consumers (rtld and libthr added), benchmarks do not show a
slow-down of the syscalls in micro-measurements, and macro benchmarks
like buildworld do not demonstrate a difference. Part of the reason is
that buildworld time is dominated by compiler, and clang already links
to libthr. On the other hand, small utilities typically used by shell
scripts have the total number of syscalls cut by half.

The syscall is not exported from the stable libc version namespace on
purpose.  It is intended to be used only by our C runtime
implementation internals.

Tested by:	pho
Disscussed with:	cem, emaste, jilles
Sponsored by:	The FreeBSD Foundation
Differential revision:	https://reviews.freebsd.org/D12773
2020-02-09 11:53:12 +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
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
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
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
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
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
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
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
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
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
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
Jeff Roberson
93f31533df Document new NUMA related syscalls and utility options.
Sponsored by:	Netflix, Dell/EMC Isilon
2018-03-24 23:58:44 +00:00
Conrad Meyer
e9ac27430c Implement getrandom(2) and getentropy(3)
The general idea here is to provide userspace programs with well-defined
sources of entropy, in a fashion that doesn't require opening a new file
descriptor (ulimits) or accessing paths (/dev/urandom may be restricted
by chroot or capsicum).

getrandom(2) is the more general API, and comes from the Linux world.
Since our urandom and random devices are identical, the GRND_RANDOM flag
is ignored.

getentropy(3) is added as a compatibility shim for the OpenBSD API.

truss(1) support is included.

Tests for both system calls are provided.  Coverage is believed to be at
least as comprehensive as LTP getrandom(2) test coverage.  Additionally,
instructions for running the LTP tests directly against FreeBSD are provided
in the "Test Plan" section of the Differential revision linked below.  (They
pass, of course.)

PR:		194204
Reported by:	David CARLIER <david.carlier AT hardenedbsd.org>
Discussed with:	cperciva, delphij, jhb, markj
Relnotes:	maybe
Differential Revision:	https://reviews.freebsd.org/D14500
2018-03-21 01:15:45 +00:00
Warner Losh
0b972ac92e Support armv7 builds for userland
Make armv7 as a new MACHINE_ARCH.

Copy all the places we do armv6 and add armv7 as basically an
alias. clang appears to generate code for armv7 by default. armv7 hard
float isn't supported by the the in-tree gcc, so it hasn't been
updated to have a new default.

Support armv7 as a new valid MACHINE_ARCH (and by extension
TARGET_ARCH).

Add armv7 to the universe build.

Differential Revision: https://reviews.freebsd.org/D12010
2017-10-05 23:01:33 +00:00
Warner Losh
5ab191c42b Forward compatibility for ino64.
Add forward compatibility so that new binaries can run on old
kernels. If the new system call from ino64 isn't available on your
system, then the old one will be used and the results translated.  The
stat and statfs families of functions are fully emulated. While not
required by policy, in this case it is helpful to our users to provide
this compatibility. In this case, it allows rollback of the kernel
after installing a new userland should a problem be discovered. It
also prevents foot-shooting if a user does an install before rebooting
with the new kernel. Finally, it allows the use case where one needs
to run new binaries on an old kernel as part of an upgrade process.

The getdirentries family uses tricks that may not work on remote
filesystems. Specifically, it uses a buffer 1/4 the size requested to
get the data from he old syscall.

The code carefully uses direct syscalls for old system calls to avoid
referencing freebsd11_* symbols, which contaminate ld-elf.so.1's
export table due to its use of stat functions, which causes errno to
be incorrect in client programs due to the wrong *stat* function being
resolved in some cases.

This code should removed sometime after 12 is branched.

Tested on: 12-current binaries on a 10.3-beta kernel run and return
       consistent results. 12-current kernel and userland with
       packages from before ino64 was committed also work.

Differential Revision: https://reviews.freebsd.org/D11185
Reviewed by: kib@, emaste@
2017-06-23 18:06:20 +00:00
Conrad Meyer
a13136cdb7 pdwait4(2): Remove documentation of vaporware
This syscall has never existed and is not at risk of existing any time soon.
Remove documentation referencing it, which has been wrong since FreeBSD 9.

Reported by:	allanjude@
2017-06-17 17:32:40 +00:00
Jilles Tjoelker
e0e0323354 libc: Remove futimens() and utimensat() compat stubs.
The futimens() and utimensat() compat stubs allowed using these functions on
kernels that did not have the system calls yet (10.2, old 11-current).

Also remove the documentation of the [ENOTSUP] error that could occur with
an old kernel.

A -DNO_CLEAN build may fail because the depend files refer to the deleted
files.
2017-06-07 21:21:14 +00:00
John Baldwin
60b67035f2 Remove stale cap_rights_get(2) manpage.
The documentation moved to section 3 several years ago, but
'man cap_rights_get' pulls up cap_rights_limit(2) (which is
MLINKed to cap_rights_get.2) instead of cap_rights_get(3).

MFC after:	1 week
2017-06-02 03:53:34 +00:00
Konstantin Belousov
6992112349 Commit the 64-bit inode project.
Extend the ino_t, dev_t, nlink_t types to 64-bit ints.  Modify
struct dirent layout to add d_off, increase the size of d_fileno
to 64-bits, increase the size of d_namlen to 16-bits, and change
the required alignment.  Increase struct statfs f_mntfromname[] and
f_mntonname[] array length MNAMELEN to 1024.

ABI breakage is mitigated by providing compatibility using versioned
symbols, ingenious use of the existing padding in structures, and
by employing other tricks.  Unfortunately, not everything can be
fixed, especially outside the base system.  For instance, third-party
APIs which pass struct stat around are broken in backward and
forward incompatible ways.

Kinfo sysctl MIBs ABI is changed in backward-compatible way, but
there is no general mechanism to handle other sysctl MIBS which
return structures where the layout has changed. It was considered
that the breakage is either in the management interfaces, where we
usually allow ABI slip, or is not important.

Struct xvnode changed layout, no compat shims are provided.

For struct xtty, dev_t tty device member was reduced to uint32_t.
It was decided that keeping ABI compat in this case is more useful
than reporting 64-bit dev_t, for the sake of pstat.

Update note: strictly follow the instructions in UPDATING.  Build
and install the new kernel with COMPAT_FREEBSD11 option enabled,
then reboot, and only then install new world.

Credits: The 64-bit inode project, also known as ino64, started life
many years ago as a project by Gleb Kurtsou (gleb).  Kirk McKusick
(mckusick) then picked up and updated the patch, and acted as a
flag-waver.  Feedback, suggestions, and discussions were carried
by Ed Maste (emaste), John Baldwin (jhb), Jilles Tjoelker (jilles),
and Rick Macklem (rmacklem).  Kris Moore (kris) performed an initial
ports investigation followed by an exp-run by Antoine Brodin (antoine).
Essential and all-embracing testing was done by Peter Holm (pho).
The heavy lifting of coordinating all these efforts and bringing the
project to completion were done by Konstantin Belousov (kib).

Sponsored by:	The FreeBSD Foundation (emaste, kib)
Differential revision:	https://reviews.freebsd.org/D10439
2017-05-23 09:29:05 +00:00
Eric van Gyzen
3f8455b090 Add clock_nanosleep()
Add a clock_nanosleep() syscall, as specified by POSIX.
Make nanosleep() a wrapper around it.

Attach the clock_nanosleep test from NetBSD. Adjust it for the
FreeBSD behavior of updating rmtp only when interrupted by a signal.
I believe this to be POSIX-compliant, since POSIX mentions the rmtp
parameter only in the paragraph about EINTR. This is also what
Linux does. (NetBSD updates rmtp unconditionally.)

Copy the whole nanosleep.2 man page from NetBSD because it is complete
and closely resembles the POSIX description. Edit, polish, and reword it
a bit, being sure to keep any relevant text from the FreeBSD page.

Reviewed by:	kib, ngie, jilles
MFC after:	3 weeks
Relnotes:	yes
Sponsored by:	Dell EMC
Differential Revision:	https://reviews.freebsd.org/D10020
2017-03-19 00:51:12 +00:00
Enji Cooper
d0fd0203fb Replace dot-dot relative pathing with SRCTOP-relative paths where possible
This reduces build output, need for recalculating paths, and makes it clearer
which paths are relative to what areas in the source tree. The change in
performance over a locally mounted UFS filesystem was negligible in my testing,
but this may more positively impact other filesystems like NFS.

LIBC_SRCTOP was left alone so Juniper (and other users) can continue to
manipulate lib/libc/Makefile (and other Makefile.inc's under lib/libc) as
include Makefiles with custom options.

Discussed with:	marcel, sjg
MFC after:	1 week
Reviewed by:	emaste
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D9207
2017-01-20 03:23:24 +00:00
Konstantin Belousov
fd6c95c09f Document thr_suspend(2) and thr_wake(2).
Reviewed by:	bjk, jilles
Discussed with:	emaste, wblock
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D8016
2016-09-26 08:18:34 +00:00
Eric Badger
5c07002e67 Add manpage for rctl_* system calls
Reviewed by:	trasz, wblock
Approved by:	kib (mentor)
MFC after:	3 days
Sponsored by:	Dell Technologies
Differential Revision:	https://reviews.freebsd.org/D7877
2016-09-19 02:25:30 +00:00
Brooks Davis
3662835abf Fix spelling in comment.
Submitted by:	brueffer
2016-09-09 16:18:44 +00:00
Brooks Davis
aec2fba60f Reduce duplicate NOASM and PSEUDO definitions
The initial value of NOASM is nearly the same in all cases and the
initial value of PSEUDO is the same in all cases so reduce duplication
(and hopefully, future merge conflicts) by machine independent defaults.

Also document the PSEUDO variable.

Reviewed by:	jhb, kib
Obtained from:	CheriBSD
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D7820
2016-09-08 22:38:20 +00:00
Konstantin Belousov
afd3e268d2 Rewrite ptrace(2) wrappers in C.
Besides removing hand-translation to assembler, this also adds missing
wrappers for arm64 and risc-v.

Reviewed by:	emaste, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D7694
2016-08-29 18:47:51 +00:00
Konstantin Belousov
174c072c00 Add fdatasync(2) man page, combined with fsync(2).
Reviewed by:	emaste, rpokala, wblock
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Differential revision:	https://reviews.freebsd.org/D7522
2016-08-17 10:16:42 +00:00
Konstantin Belousov
1c1cc89580 The fdatasync(2) call must be cancellation point.
Sponsored by:	The FreeBSD Foundation
MFC after:	13 days
2016-08-16 08:27:03 +00:00
Brooks Davis
b60998c633 Replace use of the pipe(2) system call with pipe2(2) with a zero flags
value.

This eliminates the need for machine dependant assembly wrappers for
pipe(2).

It also make passing an invalid address to pipe(2) return EFAULT rather
than triggering a segfault.  Document this behavior (which was already
true for pipe2(2), but undocumented).

Reviewed by:	andrew
Approved by:	re (gjb)
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D6815
2016-06-22 21:11:27 +00:00
Konstantin Belousov
d21ea7daaa Add thr*.2 and _umtx_op.2 manpages to the build.
Sponsored by:	The FreeBSD Foundation
2016-05-14 09:43:28 +00:00
Konstantin Belousov
96cdb0ab9d Annotate arm userspace assembler sources stating their tolerance to
the non-executable stack.

Reviewed by:	andrew
Sponsored by:	The FreeBSD Foundation
2015-09-29 16:09:58 +00:00
Bryan Drewery
cca3306a7f Avoid adding duplicates into OBJS. bsd.lib.mk already handles adding
entries to OBJS based on SRCS.

MFC after:	1 week
Sponsored by:	EMC / Isilon Storage Division
2015-09-22 04:55:28 +00:00
Pedro F. Giffuni
fe0d386cf3 Move the stack protector to a new "secure" directory
As part of the code refactoring to support FORTIFY_SOURCE we want
a new subdirectory "secure" to keep the files related to security.
Move the stack protector functions to this new directory.

No functional change.

Differential Review:	https://reviews.freebsd.org/D3333
2015-08-14 03:03:13 +00:00
Adrian Chadd
6520495abc Add an initial NUMA affinity/policy configuration for threads and processes.
This is based on work done by jeff@ and jhb@, as well as the numa.diff
patch that has been circulating when someone asks for first-touch NUMA
on -10 or -11.

* Introduce a simple set of VM policy and iterator types.
* tie the policy types into the vm_phys path for now, mirroring how
  the initial first-touch allocation work was enabled.
* add syscalls to control changing thread and process defaults.
* add a global NUMA VM domain policy.
* implement a simple cascade policy order - if a thread policy exists, use it;
  if a process policy exists, use it; use the default policy.
* processes inherit policies from their parent processes, threads inherit
  policies from their parent threads.
* add a simple tool (numactl) to query and modify default thread/process
  policities.
* add documentation for the new syscalls, for numa and for numactl.
* re-enable first touch NUMA again by default, as now policies can be
  set in a variety of methods.

This is only relevant for very specific workloads.

This doesn't pretend to be a final NUMA solution.

The previous defaults in -HEAD (with MAXMEMDOM set) can be achieved by
'sysctl vm.default_policy=rr'.

This is only relevant if MAXMEMDOM is set to something other than 1.
Ie, if you're using GENERIC or a modified kernel with non-NUMA, then
this is a glorified no-op for you.

Thank you to Norse Corp for giving me access to rather large
(for FreeBSD!) NUMA machines in order to develop and verify this.

Thank you to Dell for providing me with dual socket sandybridge
and westmere v3 hardware to do NUMA development with.

Thank you to Scott Long at Netflix for providing me with access
to the two-socket, four-domain haswell v3 hardware.

Thank you to Peter Holm for running the stress testing suite
against the NUMA branch during various stages of development!

Tested:

* MIPS (regression testing; non-NUMA)
* i386 (regression testing; non-NUMA GENERIC)
* amd64 (regression testing; non-NUMA GENERIC)
* westmere, 2 socket (thankyou norse!)
* sandy bridge, 2 socket (thankyou dell!)
* ivy bridge, 2 socket (thankyou norse!)
* westmere-EX, 4 socket / 1TB RAM (thankyou norse!)
* haswell, 2 socket (thankyou norse!)
* haswell v3, 2 socket (thankyou dell)
* haswell v3, 2x18 core (thankyou scott long / netflix!)

* Peter Holm ran a stress test suite on this work and found one
  issue, but has not been able to verify it (it doesn't look NUMA
  related, and he only saw it once over many testing runs.)

* I've tested bhyve instances running in fixed NUMA domains and cpusets;
  all seems to work correctly.

Verified:

* intel-pcm - pcm-numa.x and pcm-memory.x, whilst selecting different
  NUMA policies for processes under test.

Review:

This was reviewed through phabricator (https://reviews.freebsd.org/D2559)
as well as privately and via emails to freebsd-arch@.  The git history
with specific attributes is available at https://github.com/erikarn/freebsd/
in the NUMA branch (https://github.com/erikarn/freebsd/compare/local/adrian_numa_policy).

This has been reviewed by a number of people (stas, rpaulo, kib, ngie,
wblock) but not achieved a clear consensus.  My hope is that with further
exposure and testing more functionality can be implemented and evaluated.

Notes:

* The VM doesn't handle unbalanced domains very well, and if you have an overly
  unbalanced memory setup whilst under high memory pressure, VM page allocation
  may fail leading to a kernel panic.  This was a problem in the past, but it's
  much more easily triggered now with these tools.

* This work only controls the path through vm_phys; it doesn't yet strongly/predictably
  affect contigmalloc, KVA placement, UMA, etc.  So, driver placement of memory
  isn't really guaranteed in any way.  That's next on my plate.

Sponsored by:	Norse Corp, Inc.; Dell
2015-07-11 15:21:37 +00:00
Konstantin Belousov
0538aafc41 The lseek(2), mmap(2), truncate(2), ftruncate(2), pread(2), and
pwrite(2) syscalls are wrapped to provide compatibility with pre-7.x
kernels which required padding before the off_t parameter.  The
fcntl(2) contains compatibility code to handle kernels before the
struct flock was changed during the 8.x CURRENT development.  The
shims were reasonable to allow easier revert to the older kernel at
that time.

Now, two or three major releases later, shims do not serve any
purpose.  Such old kernels cannot handle current libc, so revert the
compatibility code.

Make padded syscalls support conditional under the COMPAT6 config
option.  For COMPAT32, the syscalls were under COMPAT6 already.

Remove WITHOUT_SYSCALL_COMPAT build option, which only purpose was to
(partially) disable the removed shims.

Reviewed by:	jhb, imp (previous versions)
Discussed with:	peter
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-18 21:50:13 +00:00
Konstantin Belousov
3d0045bb2b Make wait6(2), waitid(3) and ppoll(2) cancellation points. The
waitid() function is required to be cancellable by the standard.  The
wait6() and ppoll() follow the other syscalls in their groups.

Reviewed by:	jhb, jilles (previous versions)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-18 21:35:41 +00:00
Konstantin Belousov
b072e86d09 Make kevent(2) a cancellation point.
Note that to cancel blocked kevent(2) call, changelist must be empty,
since we cannot cancel a call which already made changes to the
process state.  And in reverse, call which only makes changes to the
kqueue state, without waiting for an event, is not cancellable.  This
makes a natural usage model to migrate kqueue loop to support
cancellation, where existing single kevent(2) call must be split into
two: first uncancellable update of kqueue, then cancellable wait for
events.

Note that this is ABI-incompatible change, but it is believed that
there is no cancel-safe code that relies on kevent(2) not being a
cancellation point.  Option to preserve the ABI would be to keep
kevent(2) as is, but add new call with flags to specify cancellation
behaviour, which only value seems to add complications.

Suggested and reviewed by:	jilles
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-03-29 19:14:41 +00:00
Marius Strobl
aed116911d Unbreak sparc64 after r276630 by calling __sparc_sigtramp_setup signal
trampoline as part of the MD __sys_sigaction again.

Submitted by:	kib (initial versions)
MFC after:	3 days
2015-02-16 22:13:03 +00:00
Jilles Tjoelker
2205e0d1bd Add futimens and utimensat system calls.
The core kernel part is patch file utimes.2008.4.diff from
pluknet@FreeBSD.org. I updated the code for API changes, added the manual
page and added compatibility code for old kernels. There is also audit and
Capsicum support.

A new UTIME_* constant might allow setting birthtimes in future.

Differential Revision:	https://reviews.freebsd.org/D1426
Submitted by:	pluknet (partially)
Reviewed by:	delphij, pluknet, rwatson
Relnotes:	yes
2015-01-23 21:07:08 +00:00
Konstantin Belousov
8495e8b1e9 Fix known issues which blow up the process after dlopen("libthr.so")
(or loading a dso linked to libthr.so into process which was not
linked against threading library).

- Remove libthr interposers of the libc functions, including
  __error(). Instead, functions calls are indirected through the
  interposing table, similar to how pthread stubs in libc are already
  done.  Libc by default points either to syscall trampolines or to
  existing libc implementations.  On libthr load, libthr rewrites the
  pointers to the cancellable implementations already in libthr.  The
  interposition table is separate from pthreads stubs indirection
  table to not pull pthreads stubs into static binaries.

- Postpone the malloc(3) internal mutexes initialization until libthr
  is loaded.  This avoids recursion between calloc(3) and static
  pthread_mutex_t initialization.

- Reinstall signal handlers with wrapper on libthr load.  The
  _rtld_is_dlopened(3) is used to avoid useless calls to sigaction(2)
  when libthr is statically referenced from the main binary.

In the process, fix openat(2), swapcontext(2) and setcontext(2)
interposing.  The libc symbols were exported at different versions
than libthr interposers.  Export both libc and libthr versions from
libc now, with default set to the higher version from libthr.

Remove unused and disconnected swapcontext(3) userspace implementation
from libc/gen.

No objections from:	deischen
Tested by:	pho, antoine (exp-run) (previous versions)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-01-03 18:38:46 +00:00
Dmitry Chagin
186d9c3473 Add the ppoll() system call.
Export kern_poll() needed by an upcoming Linuxulator change.

Differential Revision:	https://reviews.freebsd.org/D1133
Reviewed by:	kib, wblock
MFC after:	1 month
2014-11-13 05:26:14 +00:00
Warner Losh
a5fc5b6223 Convert from WITHOUT_SYSCALL_COMPAT to MK_SYSCALL_COMPAT. 2014-04-05 17:54:43 +00:00
Marcel Moolenaar
8876613dc5 Replace use of ${.CURDIR} by ${LIBC_SRCTOP} and define ${LIBC_SRCTOP}
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.

A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.

Obtained from:	Juniper Networks, Inc.
2014-03-04 02:19:39 +00:00