um: port_user: Improve error handling when port-helper is not found

Check if port-helper exists and is executable. If not, write an error
message to the kernel log with information to help the user diagnose the
issue and exit with an error. If UML_PORT_HELPER was not set, write a
message suggesting that the user set it. This makes it easier to understand
why telneting to the UML instance is failing and what can be done to fix it.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: port_user: Allow setting path to port-helper using UML_PORT_HELPER envvar

This is useful when the uml-utilities user-space package has not been
installed by the administrator and an unprivileged user wants to be able to
telnet into a UML instance. The user can install the port-helper binary to
a writable path and set UML_PORT_HELPER. Fallback to using hardcoded path to
port-helper if environment variable is not set.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: port_user: Search for in.telnetd in PATH

This allows in.telnetd to be run from non-standard installation locations
and is especially useful when running a UML instance as an unprivileged user
on a system where the administrator has not installed the in.telnetd binary.

Signed-off-by: Glenn Washburn <development@efficientek.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: Add SPDX headers for files in arch/um/drivers

Convert files to use SPDX header. All files are licensed under the GPLv2.

Signed-off-by: Alex Dewar <alex.dewar@gmx.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: Don't hardcode path as it is architecture dependent

The current code fails to run on amd64 because of hardcoded reference to
i386

Signed-off-by: Ritesh Raj Sarraf <rrs@researchut.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: get rid of pointless include "..." where include <...> will do

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

um: -include user.h for USER_OBJ, trim includes

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>

uml: fix build when SLOB is enabled

Reintroduce uml_kmalloc for the benefit of UML libc code. The
previous tactic of declaring __kmalloc so it could be called directly
from the libc side of the house turned out to be getting too intimate
with slab, and it doesn't work with slob.

So, the uml_kmalloc wrapper is back. It calls kmalloc or whatever
that translates into, and libc code calls it.

kfree is left alone since that still works, leaving a somewhat
inconsistent API.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

uml: make three functions static

Make the following three functions static, since they don't need to be global.

arch/um/drivers/mcast_kern.c::mcast_setup()
arch/um/drivers/mconsole_user.c::mconsole_reply_v0()
arch/um/drivers/port_user.c::port_pre_exec()

Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: WANG Cong <wangcong@zeuux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

uml: console subsystem tidying

This does a lot of cleanup on the UML console system. This patch should be
entirely non-functional.

The tidying is as follows:
header cleanups - the includes should be closer to minimal and complete
all printks now have a severity
lots of style fixes
fd_close is restructured a little in order to reduce the nesting
some functions were calling the os_* wrappers when they can
call libc directly
port_accept had a unnecessary variable
it also tested a pid unecessarily before killing it
some functions were made static
xterm_free is gone, as it was identical to generic_free

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

uml: Eliminate kernel allocator wrappers

UML had two wrapper procedures for kmalloc, um_kmalloc and um_kmalloc_atomic
because the flag constants weren't available in userspace code.
kern_constants.h had made kernel constants available for a long time, so there
is no need for these wrappers any more. Rather, userspace code calls kmalloc
directly with the userspace versions of the gfp flags.

kmalloc isn't a real procedure, so I had to essentially copy the inline
wrapper around __kmalloc.

vmalloc also had its own wrapper for no good reason. This is now gone.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

uml: simplify helper stack handling

run_helper and run_helper_thread had arguments which were the same in all
callers. run_helper's stack_out was always NULL and run_helper_thread's
stack_order was always 0. These are now gone, and the constants folded
into the code.

Also fixed leaks of the helper stack in the AIO and SIGIO code.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

uml: remove user_util.h

user_util.h isn't needed any more, so delete it and remove all includes of it.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] uml: port driver formatting

Whitespace and style fixes.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] uml: split memory allocation prototypes out of user.h

user.h is too generic a header name. I've split out allocation routines from
it.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] uml: const more data

Make lots of structures const in order to make it obvious that they need no
locking.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] uml console channels: remove console_write wrappers

We were using a long series of (stupid) wrappers which all call
generic_console_write(). Since the wrappers only change the 4th param, which
is unused by the called proc, remove them and call generic_console_write()
directly.

If needed at any time in the future to reintroduce this stuff, the member
could be moved to a generic struct, to avoid this duplicated handling.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] uml: separate libc-dependent helper code

The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from helper.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!