Our log functions save errno and restore it. Restoring should be
at the very end of the __print_on_level() function, but
commit 6ae4a973 ("rpc: Report back first error message on failure")
messed with it.

Move errno restore at the end of the function.

travis-ci: success for Assorted nitpicks
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

An errno from setns might be lost after close()s, so change the order.

travis-ci: success for Assorted nitpicks
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for tests: Add RPC testing to CI (rev2)
Acked-by: Andrey Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Travis sets up the GCOV variable to collect coverage and
provides an external mount for this. Thus handling this
option in RPC mode is essential.

travis-ci: success for tests: Add RPC testing to CI (rev2)
Acked-by: Andrey Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for tests: Add RPC testing to CI (rev2)
Acked-by: Andrey Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Now the --ext-mount-map is deprecated option, so fix it to
become the --external one.

travis-ci: success for tests: Add RPC testing to CI (rev2)
Acked-by: Andrey Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

It seems to me most of the clean hooks (used by cgroup*, macvlan* cr_veth*
and mnt_tracefs* were all designed to be run to clean up after the test, no
matter whether it failed or succeeded. Let's always run them, so Andrei
doesn't hate me :D

travis-ci: success for zdtm.py: run --clean hook on test failure
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
CC: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

06:46:44.191:    24: ERR: fifo_loop.c:52: can't make fifo "fifo_loop.test-00" (errno = 17 (File exists))

Reported-by: Mr Jenkins
travis-ci: success for zdtm: cleanup fifo_loop.test-0*
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Apparently, there's no clang-3.8 for Ubuntu Trusty arm64. The latest
available version is 3.6, let's try to use it.

https://travis-ci.org/kolyshkin/criu/builds/173168198Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

As recommended by [1], "Always combine RUN apt-get update with apt-get
install in the same RUN statement". Also, ditch "apt-get clean", as it
seems to be useless.

[1] https://docs.docker.com/engine/userguide/eng-image/dockerfile_best-practices/

https://travis-ci.org/kolyshkin/criu/builds/173168198
Cc: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for series starting with [1/2] ppc: Add atomic_dec_return()
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Borrowed from Linux kernel.

travis-ci: success for series starting with [1/2] ppc: Add atomic_dec_return()
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

I'm unsure where all these %%s before register names comes from,
but they confuse clang, like this:

> criu/arch/arm/parasite-head.S:6:6: error: unexpected token in operand
>  sub %r2, %pc, #8 @ get the address of this instruction
>     ^

This patch looks scary, but all it does is removing %s before
register names, fixing a few "many spaces instead of a tab" issues
along the way.

travis-ci: success for Fixes to compile on arm with clang
Cc: Christopher Covington <cov@codeaurora.org>
Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Reviewed-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

I got the following then trying to compile CRIU on ARM with clang:

> criu/cr-restore.c:2476:22: error: implicit conversion from 'unsigned
> long long' to 'unsigned long' changes value from 18446744073709551615 to
> 4294967295 [-Werror,-Wconstant-conversion]
>         return ival == -1 ? RLIM_INFINITY : ival;
>         ~~~~~~              ^~~~~~~~~~~~~
> /usr/include/arm-linux-gnueabihf/bits/resource.h:117:24: note: expanded
> from macro 'RLIM_INFINITY'
> # define RLIM_INFINITY 0xffffffffffffffffuLL
>                        ^~~~~~~~~~~~~~~~~~~~~
> 1 error generated.

Fix by using provided rlim_t type in this and similar places.

travis-ci: success for Fixes to compile on arm with clang
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Somehow clang doesn't always like -Wa flags, for example when making
dependencies (see commit 9303ed3 ("Makefiles: move -Wa,--noexecstack
out of CFLAGS"), which causes build break, scary error messages, and
even hair loss.

There are many ways to solve this. This patch employs the one
that is simple and clean.

The -Wa,-mimplicit-it=always flag was added by commit 79c4b747
("arm: fix compilation on ARMv7"). The reason is, ARM needs an IT
instruction before certain conditionals. Those IT instructions are
almost always automatically generated by assembler itself, but in some
cases a special assembler flag (like the one above) is needed.

As there is only one place in the code that need IT, it's easy to patch
it (add explicit IT) and remove the flag. Note that "IT" generates
no machine code per se, so there should not be any functional change
(although I haven't checked it).

For more info on IT, see http://tinyurl.com/z3ldsdr

Hope for a review from our ARM experts.

travis-ci: success for Fixes to compile on arm with clang
Cc: Christopher Covington <cov@codeaurora.org>
Cc: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

A couple of typos.
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Otherwise we may forget compiling binfmt_misc_virtualized code.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Do not ask kernel to transfer more opts than we really need.

When we're sending fds with flags, we ask kernel to copy the whole
struct scm_fdset::opts array, like we'd send CR_SCM_MAX_FD fds,
even if really we're transmitting only one fd.
send_fds() does not initializes the rest of array memory, but kernel
transmits this garbage. Also, recv_msg() does not return it to userspace.

This patch makes kernel do not transmit uninitialized garbage.

travis-ci: success for pie: Optimize send_fds() and recv_fds() with opts
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The need to mess with binfmt_misc super-blocks only exists
in OpenVZ kernel and troubes all the other users. So make
this code get compiled-out by default.

In VZ-builds the BINFMT_MISC_VIRTUALIZED should be put into
.config file before running make.

https://github.com/xemul/criu/issues/235
travis-ci: success for Don't compile in binfmt_misc dumping code by default (rev3)
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Reviewed-by: Dmirty Safonov <dsafonov@virtuozzo.com>

In this file one can add options with which to build CRIU.
Each line is (for now) expanded into CONFIG_$(TEXT) macros
defined in config.h that can be tested later in the code.

v2: Add .config to .gitignore
v3: Don't check that make mrproper removes .config

https://github.com/xemul/criu/issues/235
travis-ci: success for Don't compile in binfmt_misc dumping code by default (rev3)
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Reviewed-by: Dmirty Safonov <dsafonov@virtuozzo.com>

When pages are swapped out we can't detect their presence
with mincore.

Pavel found that lseek(SEEK_DATA, SEEK_HOLE) can show which
pages are used.

travis-ci: success for shmem: use lseek(SEEK_DATA) instead of mincore
Cc: Eugene Batalov <eabatalov89@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Looks-good-to: Eugene Batalov <eabatalov89@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

It is required to not dump content of the root mount in dump_one_fd().

travis-ci: success for Fix a few issues to dump/restore Docker containers with userns
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Superblock flags can be changed only an owner of the global CAP_SYS_ADMIN.

But it is posible to mount tmpfs with any flags.

travis-ci: success for Fix a few issues to dump/restore Docker containers with userns
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for Fix a few issues to dump/restore Docker containers with userns
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Part-of: Fix a few issues to dump/restore Docker containers with userns
travis-ci: success for Fix a few issues to dump/restore Docker containers with userns
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

This adds the description of --external option for all the supported
cases, both for dump and restore.

References: https://criu.org/CLI/opt/--external

travis-ci: success for Add/fix description of --external and --inherit-fd
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

First, minor/major are separated by a slash, not a semicolon.

Second, use NAME not VAL.

travis-ci: success for Add/fix description of --external and --inherit-fd
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Add that --inherit-fd may also access file_path argument, such as
in this example from wiki (see
https://criu.org/Inheriting_FDs_on_restore#Regular_files):

	$ ./test.sh > /tmp/old &
	<pid>
	$ sudo criu dump -j -t <pid>
	$ sudo criu restore -d -j --inherit-fd 'fd[7]:tmp/old' 7> /tmp/new

travis-ci: success for Add/fix description of --external and --inherit-fd
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

This patch describes the correct syntax of --inherit-fd.

travis-ci: success for Add/fix description of --external and --inherit-fd
CC: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Remove the following options (obsoleted by --external):

	--ext-unix-sk
	--veth-pair
	--ext-mount-map
	--enable-external-masters
	--enable-exteral-sharing

travis-ci: success for Add/fix description of --external and --inherit-fd
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

If userns_restore_one_link() is called outside of usernsd,
it switches into the criu namespace and switches back before exiting.

v2: rid of the include of linux/net_namespace.h in criu/include/net.h,
    as well as the associated defines and feature checks

travis-ci: success for net: simplify restore of macvlan-s (rev2)
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

It's like switch_ns, but it gets a namespace file descriptor instead of pid.

travis-ci: success for net: simplify restore of macvlan-s (rev2)
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for zdtm/cr_veth: use the --clean alias of the cleanup action
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

travis-ci: success for mnt: Deprecate --ext-mount-map for --external
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The syntax for --ext-mount-map auto is

--external mnt[]{:ms}

where optional 'm' means --enable-external-masters and optional
's' means --enable-external-sharing.

travis-ci: success for mnt: Deprecate --ext-mount-map for --external
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Make --external support --ext-mount-map. The syntax is

 --ext-mount-map KEY:VAL == --external mnt[KEY]:VAL

Old option is kept for backward compatibility.

travis-ci: success for mnt: Deprecate --ext-mount-map for --external
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Note, this depends on Pavel's patch here:
https://lists.openvz.org/pipermail/criu/2016-October/032499.html which is
not yet applied.

travis-ci: success for test: use .pid.inprogress file for macvlan test (rev2)
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>