this patch add join-ns option to criu CLI and RPC.
This opt can be used in this fomat:
	--join-ns NS:PID|NS_FILE
for example --join-ns net:12345 or --join-ns net:/foo/bar.

pid namespaces is not supported yet. As fork() is needed to make
new pid-namespace work. That makes it hard for criu to track the
child-process through pid because another child process has been
created after fork().
Signed-off-by: Deng Guangxing <dengguangxing@huawei.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The restore_bootstrap_len is restorer, args and rst-mem lenghts.

Restorer is pie_size() from restorer, which is page-size aligned.
Args len is aligned to page-size few lines above.
The remapable rst-mem grows page by page and is aligned too.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>

Currently all test mounts are mounted in the host mount namespace,
so on restore we get root with some mounts.

Cc: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Now we don't detect extra mounts, if they have peers with the same root
and target paths.
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Jenkins sends this files as a message body if something failed.

Cc: Sergey Bronnikov <sergeyb@openvz.org>
Fixes: 474f2dfc ("zdtm.py: add option --keep-going")
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Reported-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Cc: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

We were luckely on built-in tests, because always
AIO pages were present, and, thus, they are dumped.
But AIO pages are not guaranteed to be present
in common case.

This patch makes AIO pages are dumped certanly.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

nr_req always depends on ring size and we even check for that.

Kill parasite_aio::max_reqs,vma_nr_reqs and vma_area::aio_nr_req,
because they are not need and excess.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

The first is a preparation to kill aio_nr_req. The second
and the third are to have more debug info at restore.

v2: Print mmap err code
Signed-off-by: Kirill Tkhai <ktkhai@vituozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

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

This should fix errors on build envs, where git tags haven't
been fetched. I.e, Travis-ci does not fetch tags before
building a project, wich results in:
   ---> Running in 0d63a3d28a7a
  fatal: No names found, cannot describe anything.
  fatal: No names found, cannot describe anything.
  make[1]: Entering directory '/criu'

The other way is to fetch tags on `git describe` failure, but
it that way has two cons:
- it will change user's git (and I'm not sure it's right);
- we need not only fetch tags in that case, but also remotes,
  as otherwise it will fail with "fatal: No tags can describe <hash>":
  https://travis-ci.org/0x7f454c46/criu/jobs/133362045#L1748

Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

to fix error:

./crit/crit decode -i test/dump/zdtm/static/maps04/118/1/stats-dump
Traceback (most recent call last):
  File "./crit/crit", line 276, in <module>
    main()
  File "./crit/crit", line 273, in main
    opts["func"](opts)
  File "./crit/crit", line 28, in decode
    img = pycriu.images.load(inf(opts), opts['pretty'], opts['nopl'])
KeyError: 'nopl'
Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

In some images there can be quite a long "payload" -- some
raw data that is represented by base64 encoding. If we want
to explore huge images reading tons of base64 symbols can
be quite time consuming :) E.g. I a 1.5 gigs image with sysv
shmem was sent to me some time ago for investigation %)

So here is the --nopl argument for show action (decode should
produce encode-able image, so payload there is needed) that
just shows the amount of bytes in payload (if any).
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

This seems to be known problem in util-vdso.c on aarch64 [1].

Now restorer segfaults with the following log:
[ 8107.384817] criu[5135]: unhandled level 3 translation fault (11) at 0x00005b98, esr 0x90000007
[ 8107.385538] pgd = ffffffc038dbc000
[ 8107.386046] [00005b98] *pgd=0000000078d6c003, *pud=0000000078d6c003, *pmd=0000000073c31003, *pte=0000000000000000
[ 8107.391920]
[ 8107.392521] CPU: 0 PID: 5135 Comm: criu Not tainted 4.5.0 #29
[ 8107.392805] Hardware name: linux,dummy-virt (DT)
[ 8107.393140] task: ffffffc039a2a400 ti: ffffffc033c34000 task.ti: ffffffc033c34000
[ 8107.393782] PC is at 0x13514
[ 8107.406332] LR is at 0x1342c
[ 8107.406550] pc : [<0000000000013514>] lr : [<000000000001342c>] pstate: a0000000

This is because gcc for aarch64 adds vdso_symbols array to symbols
table and by that reason, it needs run-time relocations in place.

How it goes (with cut not interesting assembly):
  0x14104:	adrp	x7, 0x14000	; adrp+add loading of
  0x14114:	add	x0, x7, #0x928	; symbol table's address,
  0x14134:	ldp	x2, x3, [x0]	; loading address of symbol from
					; symbol table
  0x1414c:	stp	x2, x3, [x29,#112] ; saving it on stack on
					; function's begin
  0x14188:	ldr	x2, [x29,#112]	; using symbol's address in code

The symbol for this in symbol table is:
  [root@alarm cr]# readelf -s criu/pie/restorer.built-in.bin.o | grep 5b98
    248: 0000000000005b98     0 NOTYPE  LOCAL  DEFAULT    1 $d
And also may be visible this way:
  objdump -dS criu/pie/restorer.built-in.bin.o | less
  ...
  0000000000004924 <cur_loglevel>:
      4924:       00000002 00005b98 00000000 00005ed0     .....[.......^..
      4934:       00000000 00005ee8 00000000 00005f00     .....^......._..

So, in a symbol table lies not relocated address of symbol.
The real address may be visible with added printing of vdso_symbols[0]:
pie: vdso: vdso_symbols[0] 0x15b98
(this way gcc by some reason does access symbol through
local adrp+add calculations, than through stack-saved pointer
of a symbol from symbol table).

While we don't handling properly relocs here, I suggest this
ugly workaround.

Temporary fix for: #150

[1]: https://lists.openvz.org/pipermail/criu/2015-October/022453.html

Cc: Wang Long <long.wanglong@huawei.com>
Cc: Christopher Covington <cov@codeaurora.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Tested-by: long.wanglong <long.wanglong@huawei.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

As for compatible 32-bit pie size of uint64_t is bigger than size of
unsigned long type, add proper casts, so we could build compatible pie.
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

We are going to build everything from toplevel
for convenience (just like it was before criu 2)
so move one more snippet on top.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

They are already defined and exported.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

We use in our PCS7 packaging and I think it's
suitable for everything else as well.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

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

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

$ git log v4.4-rc1-465-gd6df198
commit d6df198d924775e4751561cf60ef0294e95f74df
Author: Phil Sutter <phil@nwl.cc>
Date:   Tue Dec 1 22:45:15 2015 +0100

    net: ipv6: restrict hop_limit sysctl setting to range [1; 255]

    Setting a value bigger than 255 resulted in using only the lower eight
    bits of that value as it is assigned to the u8 header field. To avoid
    this unexpected result, reject such values.

https://github.com/xemul/criu/issues/164Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

shmem.c:290:4: note: in expansion of macro 'pr_err'
    pr_err("Shmem %lx already collected as SYSVIPC\n", vi->shmid);
    ^

v2: fix one more place
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

====================== Run zdtm/static/mnt_tracefs in uns ======================
Start test
./mnt_tracefs --pidfile=mnt_tracefs.pid --outfile=mnt_tracefs.out --dirname=mnt_tracefs.test
Run criu dump
Wait for zdtm/static/mnt_tracefs to die for 0.100000
Run criu restore
Run criu dump
Run criu restore
Run criu dump
Run criu restore
1: Old mounts lost: set([])
1: New mounts appeared: set([('/', '/debugfs/tracing')])
Wait for zdtm/static/mnt_tracefs to die for 0.100000

Cc: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Andrew Vagin <avagin@virtuozzo.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

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

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

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

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

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

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

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

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

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

All the dumping code sits in there, so it's time to move the restoring
one there too :)
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

We have 3 structures and 2 ways to keep them while doing C/R.
Let's unify the vma_area is -- one struct with union and a
hash table.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

We now have two places where we if/elseif/elseif/else a vma
and take actions -- the prepare_mm_pid and open_vmas. I propose
to make this if/... onlce once (while preparing) and set up
a callback on vma to be called later (while opening).

This requires my patch that doesn't set -1 in alloc_vma or
Andrey's patch that does the same.
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

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

Image a process has done shmget(2 pages), then shmat() then
mprotect(1 page, ro). In this case criu will dump 1 shmem
segment 2 pages long and 2 vmas 1 page each.

But on restore time we'll call shmat() for _each_ vma and the
very first one will occupy the whole 2 pages space in vm
(there's no size argument for shmat, only for shmget) thus
blocking the 2nd vma from shmat()-in again.

The solution is:

1. check that each shmem segment is attached by
   the sequence of vmas that cover one w/o holes

2. shmat() only the first one

3. mprotect() all of them if needed (there's no hunks
   for this step in this path, mprotect is already
   called in pie/restorer.c and does things well)

v2:

* List can contain anon shmems (caught by zdtm)
* There can be many attachments of a segment (caught by transition/ipc)
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

When testing for queued data present on
peers we setup non-blocking mode over them
to obtain -EAGAIN if there is no data
at all, but I forget to restore former
mode on return, ie blocking read.
Reported-by: Andrey Vagin <avagin@virtuozzo.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

For easier reading: we need it for pty queued data only,
but this way the code is simplier.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>