Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Where possible we will use M_LINUX malloc(9) type.
Move M_FUTEX defines to the linux_common.ko.

Differential Revision: https://reviews.freebsd.org/D1077
Reviewed by: emaste

Simplify linux_getcwd(), removing code that was longer used.

Differential Revision: https://reviews.freebsd.org/D2326
Reviewed by: dchagin@, kib@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation

Modify kern___getcwd() to take max pathlen limit as an additional
argument. This will be used for the Linux emulation layer - for Linux,
PATH_MAX is 4096 and not 1024.

Differential Revision: https://reviews.freebsd.org/D2335
Reviewed by: kib@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation

Indeed, instead of hiding the kern___getcwd() bug by bogus cast
in r276564, change path type to char * (pathnames are always char *).
And remove bogus casts of malloc().
kern___getcwd() internally doesn't actually use or support u_char *
paths, except to copy them to a normal char * path.

These changes are not visible to libc as libc/gen/getcwd.c misdeclares
__getcwd() as taking a plain char * path.

While here remove _SYS_SYSPROTO_H_ for __getcwd() syscall as
we always have sysproto.h.

Pointed out by: bde

MFC after: 1 week

Cast *path to silence clang -Wpointer-sign warning.

MFC after: 1 week

Remove Giant from linux_getcwd() due to VFS is MPSAFE now.

Discussed with: kib
MFC after: 1 week

The NetBSD Foundation has granted permission to remove clause 3 and 4 from
their software.

Obtained from: NetBSD

Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with: pjd

Use shared vnode locks when invoking VOP_READDIR().

MFC after: 1 month

Introduce accmode_t. This is required for NFSv4 ACLs - it will be neccessary
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.

Approved by: rwatson (mentor)

Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>

vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by: Diego Sardina <siarodx at gmail dot com>,
Andrea Di Pasquale <whyx dot it at gmail dot com>

Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

mac_<object>_<method/action>
mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer

Add missed ")". Fix the build.

Pointy hat to: kib

Use standard debugging facilities in linux_getcwd().

Submitted by: rdivacky

Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from: TrustedBSD Project
Sponsored by: SPARTA

Unbreak COMPAT_LINUX32 option support on amd64.

Broken by: netchild

Fixup some problems in my previous commit (COMPAT_43).

Pointyhat to: netchild

Get rid of the need of COMPAT_43 in the linuxolator.

Submitted by: Divacky Roman <xdivac02@stud.fit.vutbr.cz>
Obtained from: DragonFly (some parts)

- vn_lock with LK_RETRY can not return an error. The code that handled this
case was not necessary.

Sponsored by: Isilon Systems, Inc.

Fix -Wundef.

Add Giant around linux_getcwd_common() in linux_getcwd().

Approved by: re (scottl)

- Change all filesystems and vfs_cache to relock the dvp once the child is
locked in the ISDOTDOT case. Se vfs_lookup.c r1.79 for details.

Sponsored by: Isilon Systems, Inc.

- Initial cn_lkflags to LK_EXCLUSIVE.

Sponsored by: Isilon Systems, Inc.

Match the LINUX32's style with existing style
Submitted by: Jung-uk Kim <jkim@niksun.com>

Use positive, not negative logic.

Changes to MI Linux emulation code necessary to run 32-bit Linux binaries
on AMD64, and the general case where the emulated platform has different
size pointers than we use natively:
- declare certain structure members as l_uintptr_t and use the new PTRIN
and PTROUT macros to convert to and from native pointers.
- declare some structures __packed on amd64 when the layout would differ
from that used on i386.
- include <machine/../linux32/linux.h> instead of <machine/../linux/linux.h>
if compiling with COMPAT_LINUX32. This will need to be revisited before
32-bit and 64-bit Linux emulation support can coexist in the same kernel.
- other small scattered changes.

This should be a no-op on i386 and Alpha.

Add a MAC check for VOP_LOOKUP() in the Linux getwcd() implementation.

Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories

Use __FBSDID().

Backout the getcwd changes, a more comprehensive effort will be needed.

(This commit certainly increases the need for a wash&clean of vfs_cache.c,
but I decided that it was important for this patch to not bit-rot, and
since it is mainly moving code around, the total amount of entropy is
epsilon /phk)

This is a patch to move the common parts of linux_getcwd() back into
kern/vfs_cache.c so that the standard FreeBSD libc getcwd() can use it's
extended functionality. The linux syscall linux_getcwd() in
compat/linux/linux_getcwd.c has been rewritten to use it too. It should
be possible to simplify libc's getcwd() after this. No doubt this code
needs some cleaning up, since I've left in the sysctl variables I used
for debugging.

PR: 48169
Submitted by: James Whitwell <abacau@yahoo.com.au>

Back out M_* changes, per decision of the TRB.

Approved by: trb

Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.

Use the new kern_*() functions to avoid using the stack gap in
linux_fcntl*() and linux_getcwd().

- Replace v_flag with v_iflag and v_vflag
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.

Idea stolen from: BSD/OS

Introduce support for Mandatory Access Control and extensible
kernel access control.

Invoke appropriate MAC entry points for a number of VFS-related
operations in the Linux ABI module. In particular, handle uselib
in a manner similar to open() (more work is probably needed here),
as well as handle statfs(), and linux readdir()-like calls.

Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs

Remove __P.

Simple p_ucred -> td_ucred changes to start using the per-thread ucred
reference.

Fix warning in debug printf. This is a long on alpha, and int on i386,
but printed with %ld always.

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

Fix linux_getcwd() so that if the cwd isn't cached (__getcwd() fails),
the cwd is looked up inside the kernel. The native getcwd() in libc
handles this in userland if __getcwd() fails.

Obtained from: NetBSD via OpenBSD
Tested by: Chris Casey <chriss@phys.ksu.edu>, Markus Holmberg <markush@acc.umu.se>
Reviewed by: Darrell Anderson <anderson@cs.duke.edu>
PR: kern/24315