This reverts commit 4778cb30.

cpuset.cpus and cpuset.mems can't be written to for the first time after they
have tasks, so the traditional mechanism of restoring properties after
restoring the tasks won't work here. Instead, we copy the parent values of the
properties into them, restore the tasks, and then restore via the traditional
mechanism the actual values of these properties.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

In particular, cpuset.cpus and cpuset.mems can both be "lists" (strings), as
well as hex integers. We don't use the result of this parse, so it is fine to delete it.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The AUFS support code handles the "bad" information that we get from
the kernel in /proc/<pid>/map_files and /proc/<pid>/mountinfo files.
For details see comments in sysfs_parse.c.

The main motivation for this work was dumping and restoring Docker
containers which by default use the AUFS graph driver.  For dump,
--aufs-root <container_root> should be added to the command line options.
For restore, there is no need for AUFS-specific command line options
but the container's AUFS filesystem should already be set up before
calling criu restore.

[ xemul: With AUFS files sometimes, in particular -- in case of a
  mapping of an executable file (likekely the one created at elf load),
  in the /proc/pid/map_files/xxx link target we see not the path
  by which the file is seen in AUFS, but the path by which AUFS
  accesses this file from one of its "branches". In order to fix
  the path we get the info about branches from sysfs and when we
  meet such a file, we cut the branch part of the path. ]
Signed-off-by: Saied Kazemi <saied@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

Look at this strace output:
107   linkat(45, "", 1017, "./root/git/orig/criu/test/zdtm/live/static/unlink_fstat03.test (deleted)/link_remap.4", AT_EMPTY_PATH) = -1 ENOENT (No such file or director

It's obvious, that we didn't cat the file name.

Here is an error in calculation of offset for the last symbol.
The current version of code sets this offset in strlen(),
but it's actually strlen() - 1.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

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

We've moved signinfos on core entry, thus the bits with
siginfo-s themselves cannot sit on stack any longer.
Otherwise we would overwritem them with next batch and
will feed stack pointer to the caller, thus causing a
data and garbage on the stack to be written into image
instead of siginfo data.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The se variable is just an array of pointers on these
objects. Need to allocate the objects themselves.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

And sanitize its usage a little bit.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

No need in extra variable for that.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It fails on moving tasks into cpuset due to empty masks. Temporary
disable the test.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

After this patch, signal-s*.img won't be created.

v2: just move them to the end of array
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Every thread has it's own private signals stored at thread_core->signals_p
and leader thread has also shared signals stored at tc->signals_s.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We need it to be able to dump signals into cores
before calling parasite_infect_seized().
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

In order to save backward compatibility, criu will try to open signal*.img,
if no signals_* are found.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We need to open cores for each thread early, because we'll need them to
prepare signals later.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Add signal_queue_entry signals_s for shared signals to task_core_entry
and signals_p for private signals to thread_core_entry.
Signed-off-by: Ruslan Kuprieiev <kupruser@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The task_entries is a small structure used to coordinate the
processes restore stages. Currentl we allocate one page for
it and handle one separately. No need in this complexity, actually.
The rst_mem engine is already capable to controll this small object.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

This is a position in the RM_SHREMAP memory. Since shmems are currently
the only user of it, this is validly equals zero, but it will change soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The motivation for this is to be able to restore containers into cgroups other
than what they were dumped in (if, e.g. they might conflict with an existing
container). Suppose you have a container in:

memory:/mycontainer
cpuacct,cpu:/mycontainer
blkio:/mycontainer
name=systemd:/mycontainer

You could then restore them to /mycontainer2 via --cgroup-root /mycontainer2.
If you want to restore different controllers to different paths, you can
provide multiple arguments, for example, passing:

--cgroup-root /mycontainer2 --cgroup-root cpuacct,cpu:/specialcpu \
--cgroup-root name=systemd:/specialsystemd

Would result in things being restored to:

memory:/mycontainer2
cpuacct,cpu:/specialcpu
blkio:/mycontainer2
name=systemd:/specialsystemd

i.e. a --cgroup-root without a controller prefix specifies the new default root
for all cgroups.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Transition and streaming tests can create many processes
which are using cpu. CPU should be divided between tests fairly.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

When writing the system default for memory.limit_in_bytes (which is a LLONG_MAX)
the write fails. The number is equivalent to -1 (unlimited). So during dump,
store the number -1 instead.

Change-Id: Iafccc96bf5dbade763d7addaeda24194616e4d5f
Signed-off-by: Garrison Bellack <gbellack@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Needed for future user namespace support. Capabilities will have to be
dumped from the parasite, ie from inside the namespace since there is no
obvious way to 'translate' capabilities from the global namespace (unlike
with uids and gids, where the id mappings can be used for translation).

[ additional explanation from Andrew Vagin:

"capabilities" are not translated between namespaces. They can exist
only in one userns, where a process lives. If a process is created in a
new userns, it gets a full set of capabilities in this userns, and
loses all caps in a parent userns.

So if capabilities are not shown in /proc/pid/stat, we have no way to
get it except of using parasite code. ]
Signed-off-by: Sophie Blee-Goldman <ableegoldman@google.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Moves the definition of kerndat_init() to below the definition
of get_last_cap(). Needed for reading capabilities in a future patch.
Signed-off-by: Sophie Blee-Goldman <ableegoldman@google.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Just to make sure we're not loosing signals
after restore.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Because different kernel versions have different cgroup properties, criu
shouldn't crash just because the properties statically listed aren't exact.
Instead, during dump, ignore properties the kernel doesn't have and continue.

Change-Id: I5a8b93d6a8a3a9664914f10cf8e2110340dd8b31
Signed-off-by: Garrison Bellack <gbellack@google.com>
Acked-by: Tycho Andersen <tycho.andersen@canonical.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We run tests concurrently and they can race for equal resources

v2: fix hooks too
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We found a bug, when a second cgroup is restored incorrectly,
so let's create one more empty cgroup.
Signed-off-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

prepare_cgroup_dirs() gets a path and an offset.
Then we add substrings to the source string and handle them.

v2: fix one more place in prepare_cgroup_dir_properties()

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

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

When we open tty, we don't want to set it as controlling terminal.

[xemul: We do it in all the other places, this one is forgotten.
 The "controlling tty" feature is setup explicitly later with
 the ioctl (TIOCSCTTY) call. ]

This bug was caught by pty04. Where we get unexpected SIGCONT,
which is sent after closing a controlling terminal.

./pty04 --pidfile=pty04.pid --outfile=pty04.out
Dump 9578
Restore
Test: zdtm/live/static/pty04, Result: FAIL
==================================== ERROR ====================================
Test: zdtm/live/static/pty04, Namespace:
Dump log   : /home/jenkins/workspace/Rpi-CRIU/test/dump/static/pty04/9578/1/dump.log
--------------------------------- grep Error ---------------------------------
------------------------------------- END -------------------------------------
Restore log: /home/jenkins/workspace/Rpi-CRIU/test/dump/static/pty04/9578/1/restore.log
--------------------------------- grep Error ---------------------------------
(00.083420) Error (cr-restore.c:1092): 9578 killed by signal 0
(00.083708) Error (cr-restore.c:1713): Restoring FAILED.
------------------------------------- END -------------------------------------
================================= ERROR OVER =================================

Reported-by: Mr Jenkins
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It's been discovered that on 3.11 we might fail on restore
if pass @CLONE_PARENT flag into clone() call due to kernel
limitations.

Because we're treating 3.11 as a base working kernel lets
do a trick instead

 - setup this flag iif pdeath_sig is present
 - if CLONE_NEWPID is passed warn a user about
   potential consequences.
 - because we need to carry the condition in attach_to_tasks
   call, introduce @root_as_sibling variable for this.

CC: Tycho Andersen <tycho.andersen@canonical.com>
CC: Pavel Emelyanov <xemul@parallels.com>
CC: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

I didn't find a way how to do that with help "unshare".
It's simpler to write this program. It looks better than tricks in
zdtm.sh.

v2: proxify exit status
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Ruslan Kuprieiev <kupruser@gmail.com>
Acked-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>