Do not restore it yet -- the logic we're about to apply to
resolve tasks' paths relative to dumper/restorer is not yet
clear to me and it should better be hidden into a couple of
calls (dump_one_reg_file/open_fe_fd). But since we can't
chroot to fd we're about to expose the logic outside of the
open_fe_fd, which is not desirable ATM.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Why? Because one day we'll support various CLONE_ flags and
for fdtable and fs info we'd like to have separate images (since
these objects are separate in kernel).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The regfile's ID of a VMA is stored in its shmid field. And the
file itself if sumped into regfiles.img image with 'special'-ly
generated ID (i.e. -- just allocate a new unique one).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It's an O(n) algorithm.

Now we iterate both lists simultaneously to find a hole.

[xemul: Discussion making the patch more understandable:

Cyrill:

	If s_vma is the last one on self_vma_list you could break immediately, no?

	And the snippet I somehow miss is -- how the situation handled when

		      hole
		    a      b
	source |----|      |-----|
	target   |----|      |-----|
		      c      d

	the hole fits the requested size but the hole is shifted
	in target, so that you've

	prev_vma_end = a

	and then you find that a - d > vma_len and return a
	as start address for new mapping while finally it
	might intersect with address c.

	Or I miss something obvious?

Andrey:

	Look at "continue" one more time.
	prev_vma_end is returned only if both condition are true

	if (prev_vma_end + vma_len > s_vma->vma.start) {
	....
	if (prev_vma_end + vma_len > t_vma->vma.start) {
	...
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Looks-good-to: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Because amount of entries are known.
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>

[ xemul: The fix effectively is -- stop scanning the 2nd vma list
         once we see, that the hint's end hits the next vma ]
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

A file pointed by an fd should be not unlinked
and be open-able with the provided path (overmounts
and/or renames coupled with links can screw it up).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

In case if no goals specified the all
goal is implied so don't forget to generate
deps. This as well fixes a problem where
two "make clean" in a row forced build system
to regenerate deps.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Looks-good-to: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

It was required before we switched to socketpair restore
scheme. Now it's not required, sockets just connect to
the peer they want to.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

No image copy occurs since 2b175282, so this
fd can be hidden. Thus fixind the FIXME near it :)
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

"Has not" + noun is obsoleted and very rare English. Fix it.
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

rasite_cure_seized frees parasite_ctl
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>

Introduce and use generic file_desc ops for this.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

No need in per-type hash tables and search routines. We can
handle it via generic file_desc structure. Some more thoughts
on unixsk and pipe lists are still required :(
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

The struct replaces bare list_head on all of the _info-s we've
introduced recently.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

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

This is a big change, yes. Dump unix sockets in the same manner
as all the other files are done now. A few notes however.

1. We explicitly drop names for connected stream sockets. This is
   done to avoid conflicts with names -- accepted sockets share their
   names with the listening parent. This can be done later by binding
   a socket to a name, them renaming it to some temporary uniq one
   and at the very very end renaming some back to original.

2. Interconnected sockets are restored via socketpair() call. This is
   correct, but names are dropped. Need to bind() sockets after this
   (yes, this can be done), but for this we need to implement the trick
   with renames described before.

3. FD for socket queues is constantly re-opened not to resolve fd
   conflicts. Need to use service fds engine for this later.

4. Some code cleanup is still required, yes (will follow shortly).
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: Pavel Emelyanov <xemul@parallels.com>

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

A pipe buffer has 16 slots. A slot is page, offset and size.
When we use splice and data is not aligned, splice connects
a page from file cache and set offset. For this reason we loose
a part of buffer.

If a data size is more than 15 pages, data will be aligned in a image.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

[xemul: This check in open_transport_fd should go away once we
        implement opening files with peers. ]
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

For example it's pipe.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

pipe_entry is encapsulated in pipe_info.
All pipe_info-s connects in the list pipes.
All pipe_info-s with the same piep_id connects to pipe_list,
it a circular list without a defined head.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

They will be used to restore pipes
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>

Information about pipe's file structs saved in one global file and
fdinfo_entry is saved for each descriptor
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

[ xemul: I don't know how to make this with incremental changes either,
         and just go with it :( ]
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

* create pipe
* write a maximum amount of data
* suspend/resume
* check that all data have been restored
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 was used in old code, now it can be dropped
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Add two checks -- that peer exists and it we will be able to
connect to him somehow on restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

This maybe not 100% correct in the generic case, but the way unix sockets are
used lets us do this trick.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

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

No need in separate per-type fn for doing this. We can just
find the respective fd list and do sorting in the generic code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>