Only two fields are modifiable -- hostname and domainname. So
read them on dump and write on restore.

File format is simple --

u32 magic
u32 length of nodename
u8[] nodename string
u32 length of domainname
u8[] domainname string

For OpenVZ we can write the release at the end, but this is later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

New option -n to dump/restore namespaces.

Fork the namespaces dumping task and write a helper for switching a namespace.

Prepare the restorer code for restoring namespaces before root task.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

In order to restore task in namespaces we'll have to clone() them,
not fork. Thus switch the restorer into using clone.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

I will need them in the place where we restore the root task.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Split the CR_FD_ bits into per-task and global ones and replace
of CR_FD_DESC_NOPSTREE with CR_FD_DESC_TASK, which is explicit
set of per-task bits.

The CR_FD_DESC_NS will appear soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Usefull for debugging.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Andrey Vagin <avagin@gmail.com>

Cleanup and simplifyng (as requested).
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Andrey Vagin <avagin@gmail.com>

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

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

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

Common code for all makefiles.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

This is more informative to know which exactly name failed.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>

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

And increase the timeout value, since the timers test checks for counters
for more than 5 seconds...
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Timers are dumped from inside parasite code, the format is plain -- just
3 pairs of interval/value one-by-one.

The restoration occurs in two stages -- first prepare the timer values in
restorer (and check for sanity), then setup the timers in the latest stage
before actually calling the sigreturn.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

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

Move the common file-opening code into a separate function.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

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

Just move common code of preparing a file for parasite.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Remove typedefs and make the common part of sigacts and pages dumping arguments
for dumping something into a specific file. Will be used almost as-is soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

To test restore of commandline, envirion
and auxv vector.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>

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

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

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

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

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

It's needed for auxv dump and restore.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>

It implies update to kernel side as well.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>

Compile it as a separate file and use ld to merge two
files.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrey Vagin <avagin@openvz.org>

Test that 2 different exit()-ed zombies and 2 killed with different
signals are handled properly.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Dump the core-pid.img file only. On restore select the way of killing
task based on his exit_code -- exit or kill with a signal. Before dying
unblock all the handlers and set SIG_DFL to it (to make the dead signal
other than KILL be deliverable).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

The absent image file on shared resources preparation now means -- no resources
for this pid (zombies will not have these files).

This is not the most elegant solution, but I don't have anything better in mind.
Need to think over, all the more so we're most likely about to reimplement the
way image is stored some day in the future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Don't dump tasks in any state but T (stopped). Will extend it with Z soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Introduce 3 states we will have to work with:

* alive for tasks sleeping or running
* dead for zombies
* stopped for stopped tasks. We cannot distinguish tasks in this state now,
  but with freezer cgroup this will become possible
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Requires patch #14 (for kernel). Also check for number of entries read be
at least required, not exactly equal for forward compatibility.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Move common code for tasks and threads dumping into routine. It will be
used for zombies as well.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Kill all the macros for reading/writing image parts. New API looks like

* write_img_buf/write_img
  Write an object into an image. Reports 0 for OK, -1 for error. The _buf
  version accepts object size as an argument, the other one uses sizeof()

* read_img_buf/read_img
  Reads an object from image. Reports 0 for OK, -1 for error or EOF.

* read_img_buf_eof/read_img
  Reads an object from image. Reports 1 for OK, 0 for EOF and -1 for error.
  This is not symmetrical with the previous one, but it was done deliberately
  to make it possible to write code like

  ret = read_img_bug_eof();
  if (ret <= 0)
	return ret; /* 0 means OK, all is done, -1 means error was met */.

  ... /* 1 means object was read, can proceed */
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Keep task arch-independent fields in one struct (will be extended) in the
beginning of the image and make pads be located separately.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

Rename prep_cr_fdset_for_dump into cr_fdset_open and make it reentable, i.e.
every next enter will open more files in the same fdset. Required for zombies
and makes the code cleaner.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>