lib{c,sys}: return wrapped syscall APIs to libc

These provide standard APIs, but are implemented using another system
call (e.g., pipe implemented in terms of pipe2) or are interposed by the
threadi

lib{c,sys}: return wrapped syscall APIs to libc

These provide standard APIs, but are implemented using another system
call (e.g., pipe implemented in terms of pipe2) or are interposed by the
threading library to support cancelation.

After discussion with kib (see D44111), I've concluded that it is
better to keep most public interfaces in libc with as little
as possible in libsys.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44241

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memfd_create: move implementation to libc/gen

Due to memfd_create(3)'s construction of a path to pass to shm_open2(2),
it has a much larger than typical dependency footprint for a system
call wrappe

memfd_create: move implementation to libc/gen

Due to memfd_create(3)'s construction of a path to pass to shm_open2(2),
it has a much larger than typical dependency footprint for a system
call wrapper (the list currently includes calloc, memset, sprintf, and
strlen). As such, split it off into its own file under libc/gen to
lighten libc/sys's dependency list.

Reviewed by: kevans, imp, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D42709

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libc: Purge unneeded cdefs.h

These sys/cdefs.h are not needed. Purge them. They are mostly left-over
from the $FreeBSD$ removal. A few in libc are still required for macros
that cdefs.h defines. Kee

libc: Purge unneeded cdefs.h

These sys/cdefs.h are not needed. Purge them. They are mostly left-over
from the $FreeBSD$ removal. A few in libc are still required for macros
that cdefs.h defines. Keep those.

Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D42385

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Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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Fix error checking in shm_create_largepage().

Reviewed by: alc, kib
Reported by: Coverity
MFC with: r365524
Differential Revision: https://reviews.freebsd.org/D26464

memfd_create: simplify HUGETLB support a little bit

This also fixes a minor issue that was missed in the initial review; the
layout of the MFD_HUGE_* flags is actually not 1:1 bit:flag -- it instead

memfd_create: simplify HUGETLB support a little bit

This also fixes a minor issue that was missed in the initial review; the
layout of the MFD_HUGE_* flags is actually not 1:1 bit:flag -- it instead
borrowed the Linux convention of how this is laid out since it was
originally implemented on Linux, the top 6 bits represent the shift required
for the requested page size.

This allows us to remove the flag <-> pgsize mapping table and simplify the
logic just prior to validation of the requested page size.

While we're here, fix two small nits:

- HUGETLB memfd shouldn't exhibit the SHM_GROW_ON_WRITE behavior. We can
only grow largepage shm by appropriately aligned (i.e. requested pagesize)
sizes, so it can't work in the typical/sane fashion. Furthermore, Linux
does the same, so let's be compatible.

- We don't allow MFD_HUGETLB without specifying a pagesize, so no need to
check for that later.

Reviewed by: kib (slightly earlier version)

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memfd_create: fix return values

Literally returning EINVAL from a function designed to return an fd makes
for interesting scenarios.

I cannot assign enough pointy hats to cover this one.

Fix memfd_create tests after r365524

r365524 did accidentally invert this check that sets SHM_LARGEPAGE, leading
non-hugetlb memfd as unconfigured largepage shm and thus test failures when
we try to

Fix memfd_create tests after r365524

r365524 did accidentally invert this check that sets SHM_LARGEPAGE, leading
non-hugetlb memfd as unconfigured largepage shm and thus test failures when
we try to ftruncate or write to them.

PR: 249236
Discussed with: kib

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Add shm_create_largepage(3) helper for creation and configuration of
largepage shm objects.

And since we can, add memfd_create(MFD_HUGETLB) support, hopefully
close enough to the Linux feature.

Rev

Add shm_create_largepage(3) helper for creation and configuration of
largepage shm objects.

And since we can, add memfd_create(MFD_HUGETLB) support, hopefully
close enough to the Linux feature.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24652

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memfd_create: turn on SHM_GROW_ON_WRITE

memfd_create fds will no longer require an ftruncate(2) to set the size;
they'll grow (to the extent that it's possible) upon write(2)-like syscalls.

Reviewe

memfd_create: turn on SHM_GROW_ON_WRITE

memfd_create fds will no longer require an ftruncate(2) to set the size;
they'll grow (to the extent that it's possible) upon write(2)-like syscalls.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D25502

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libc: remove shm_open(2)'s compat fallback

This had been introduced to ease any pain for using slightly older kernels
with a newer libc, e.g., for bisecting a kernel across the introduction of
shm_o

libc: remove shm_open(2)'s compat fallback

This had been introduced to ease any pain for using slightly older kernels
with a newer libc, e.g., for bisecting a kernel across the introduction of
shm_open2(2). 6 months has passed, retire the fallback and let shm_open()
unconditionally call shm_open2().

Stale includes are removed as well.

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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.

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)

Add SPDX tags to recently added files

Reported by: Pawel Biernacki

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.

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 qem

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

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lib{c,sys}: return wrapped syscall APIs to libc

These provide standard APIs, but are implemented using another system
call (e.g., pipe implemented in terms of pipe2) or are interposed by the
threadi

lib{c,sys}: return wrapped syscall APIs to libc

These provide standard APIs, but are implemented using another system
call (e.g., pipe implemented in terms of pipe2) or are interposed by the
threading library to support cancelation.

After discussion with kib (see D44111), I've concluded that it is
better to keep most public interfaces in libc with as little
as possible in libsys.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D44241

show more ...