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

And clean util.c and crtools.c from image manupulation code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It may occur that the loop spins faster than clock ticks.
Signed-off-by: Evgeny Antyshev <eantyshev@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Looks-cool-to: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

expr prints a substing length. This patch redirects output of expr to /dev/null
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It requered 1m19s for executing all tests.
Now it requires 38s.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

Sometime we need sync points in testee program flow,
for this reason task_waiter_ introduced.

The call semantics is the following

        Parent                  Child
        ------                  -----
        task_waiter_init
                                task_waiter_wait4
        task_waiter_complete
                                task_waiter_wait4
        task_waiter_complete

                ...

Thus initially task_waiter_init should be called
to initialize all internals guts needed.

Then one become waitee and calls for task_waiter_wait4,
where lockid should be provided as an argument. Since
it should be unique values the best option might be
gettid().

The same applies to a waiter side -- it should call
for task_waiter_complete and provide a lockid.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrey Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Strictly speaking we have to close all fds before reopening them from the
image. This can be done using not yet merged nextfd syscall, but it's not
yet merged :( By now just close std and 255 (bash's) descriptors. This is
ugly, but I prefer to wait for the nextfd syscall.

But skip the init tasks' stds becase the existing zdtm implementation
uses system() in such tasks which doesn't work when all fds are closed.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Test with sysfs and proc as no other fs-s are currently supported.
Will be fixed later.

Note, that the original /proc mount is kept as the dumping code requires
it for reading pagemap file with RSS info. Worth fixing it some day?
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

We need own proc for restoring mount namespace, since the proc should
be umounted and mounted back diring namespace restore and I don't want
to introduce a special kludge for this.

One more notice -- the temp proc is mounted _after_ namespaces recreation
for the same reason (it will be umounted by prepare_mnt_ns).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Only support virtual filesystems mount. No bindmounts or disk fs
due to non trivial resolving of devices names and binmount sources.
Will be implemented later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The tree should already be sorted, thus the call for umount shouldn't fail.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Two walkers -- in forward and reverse directions -- are required
for correct (u)mounting of subtrees. Implement them using a helper
macro which walks the tree in both directions.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Namespace restore goes in two steps -- first, clean old mountpoints
(except root) that are left after clone(CLONE_NEWNS) call. Next,
repopulate the namespace with new mountpoints (except root) read
from the image file.

This patch adds the skeleton for the above -- reading the mountpoints
from current proc and image and calling for mount/umount. The real
action will come in further patches.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

Build a tree of mountpoins that can be (u)mounted in a straight
(forward or backward) order without EBUSY errors.

The tree is built in two steps -- first create hierarchy based
on mount iDs. Next -- resort siblings in the path depth order.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Encode it in u32 since we have to check filesystem name anyway
(not everyone ie easily migratable).

Dump _any_ root fs as we need the root entry on restore though
do not mount it then -- it should be provided before crtools
restore start.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Dumping is straightforward -- just copy all the mount_info
fields into the new image file. Dump everything but fstype,
this one will come in a separate patch.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

This structure will be used on restore and will be created
from the image, thus the name proc_ is not suitable.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

On the restore path this structure will be used and it
will be better to have them char * rather than char[64].

When scanning proc use the %ms specifier for this.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It's not required more, because parasite_status_t was removed.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

In olden times, when people didn't know how to write,
they sent a courier with a letter.

Now we can write messages from parasite, so SET_PARASITE_RET may be dropped.
Signed-off-by: Andrey Vagin <avagin@openvz.org>

Looks good to me as well. Maybe we will refine messages to be able
to identify where exactly parasite failed (say line). But it better
to do in another patch.
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

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

 - add argument names
 - align members
 - add extern kw
 - group struct decl. on top
 - make file_desc_ops::type being unsigned
   integer similar to fdtype_ops::type
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

These are declared in files-reg.h, so get rid of
them and add files-reg.h inclusion where needed.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

* check, that pseudoterminals are restored
* check, that a control terminal is restred
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

    2     2 session00
    4     4  \_ session00		# {NEWSID, },
    2     5  \_ session00		# {0, },
    8     8  \_ session00
    2     9  |   \_ session00           # {CHANGESID, }
   10    10  \_ session00
   11    11      \_ session00
    2    12          \_ session00	# {DOUBLE_CHANGESID | CHANGESID, }
    2     3 session00			# {DETACH, },
    6     7 session00			# {DETACH|NEWSID, },
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Don't fail if a root non-init task has another sid, because
it's inherited from parent and can't be restored and
it's expected behaviour, when a subtree is dumped.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Now crtools can restore sid in all cases.
A restore of pgid will be added soon and now it will fail on restore.

It's prevent testing of restoring SIDs.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It's sign, that a parent has been changed sid after forking a child.
We should know a sid with which a process was born, because in a processes
chain, more then one process might change SID.

v2: fix names of variables
v3: prevent rewriting of born_sid
v4: Abort the restorer with error message if a born_sid can't be determing.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

* Create helpers for processes which have been reparented to init.
* Insert helpers in a process tree.
* Helpers will exit after constructing a process tree.

v2: fix variables names and check errors
v3: add comments in code
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

They will be used for restoring sid. For example, if a session
group leader is absent, a helper process is created with this id
and it will die after restoring all other tasks.

Before this patch restore failed if anyone exited.
Now we should skip helpers, which exited successfully. It's a bit tricky.
All children are collected in sigchld_handler, but we have a point,
where we want to wait all helpers. For that waitpit is used and ECHLD
is ignored, because it signs that a helper exited and has been waited in
sigchld_handler.

v2: check that me isn't NULL in the sig handler
v3: move code about waiting helpers in a separate function
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It will be used for allocating PIDs for helper tasks
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

s/pid/virt/
s/real_pid/real/
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

to require dumping pid namespace. Dump and restore will be failed if
a tress doesn't contain a process init.

pid namespace will be created implicitly if a process init in the tree.

v2: fix comments from Pavel
v3: Restore of pidns should be approved by user
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Current if/if/else scheme is ... not so easy to understand. Here's an
attempt to make it more readable. Bonus: free comments.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>