The main reason for this is -- dumping namespace has a lot of
points when the process just waits for something. At the same
time criu process wait for the ns dumper and doesn't dump
others.
The great example of waiting for something is setns syscall.
Very often it calls synchronize_rcu() which can be quite long.
Let other processes do smth useful while this.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Nowadays this routine is mainly used for getting an
fd, rather than keeping one for future reference.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It will fill mntinfo list and this is internal logic of mount.c
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to support nested mount namespaces and each NS has own
tree. The mount tree is used for checking that a file is reachable.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
because we want to check, that all files are reachable.
For that we need to collect all mounts from all namespaces.
v2: dump mntns separately
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Now we supports sub-mntns, so root_ns_mask sounds more correct than
current_ns_mask.
v2: typo fix
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
v2: another attempt to write readable code:)
v3: clean up
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Known issue:
* currently only namespaces with the same root is supported
* nested namespaces can be dumped and restored only if the root task
has own mount namespace.
All nested namespaces are restored in a root namespace in temporary
directories. All mount points restored in one tree and then they are
divided into namesaces.
The task with minimal pid for each namespaces unshared mntns and
then it makes pivot_root in a proper temporary directory. All other
tasks makes setns to enter into a mount namespace of the task with
minimal pid.
v2: clean up
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently ns_ids list is filled only on dump. Soon we'll need this
list for mount namespaces on restore, e.g. to know which tasks share
the namespaces.
v2: merge the patch "namespace: add a function to search an ns_id
item by id" into this one.
v3: add prefix rst_ to add_ns_id
v4: look up namespace by two values -- type AND ID
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have a condition
BUG_ON(kid > UINT_MAX);
but kid is unsigned int so it's never bigger than UINT_MAX,
use unsigned long instead.
CID 1042296
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's going to be used for restoring namespaces. For example we need to
enumirate the ns_ids list for restoring mount namespaces.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Well, we want to pre-dump files (fsnotifies), for that we
will need mountinfo-s and root, and for the latter -- the
current ns mask.
The problem with current ns mask is that its generation is
incorporated into ns IDs generation and dumping. And since
the ids dumping is not performed on pre-dump, let's just
provide a helper for ns-mask generation.
Strictly speaking, the whole ns-mask idea is not great, but
it's to be fixed later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Remove whitespace at EOL (found by git grep ' $')
To people using vim, I'd suggest adding the following code to ~/.vimrc:
let c_space_errors = 1
highlight FormatError ctermbg=darkred guibg=darkred
match FormatError /\s\+$\|\ \+\t\|\%80v.\|\ \{8\}/
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Before this patch only namespaces of the root task are dumped.
Now we dump all namespace, which have been collected.
I'm not sure, that we want to create a new process for each namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Before we dumped namespace of the root task only.
Now we are going to dump nested namespaces, so we need to know a pid of
any process, which lives in the target namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to replace pid on id in names of image files. The id is
uniq for each namespace, so it's more convient, if image files are
opened per namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to replace pid on id in names of image files. The id is
uniq for each namespace, so it's more convient, if image files are
opened per namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to replace pid on id in names of image files. The id is
uniq for each namespace, so it's more convient, if image files are
opened per namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We are going to replace pid on id in names of image files. The id is
uniq for each namespace, so it's more convient, if image files are
opened per namespace.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's preparation to replace pid on id in image names.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have generic do_pb_show() call and tons of show_foo
routines, that just call one with proper args. Compact
the code by putting the args into array and calling
the do_pb_show() in one place.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
These contain linkage between number, data type and routines
for pb messages we write/read to/from image files. Most of them
have simple number-type-routines mapping, so introduce a generating
script for that.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Since *all* of them just call do_dump_gen_file with proper ops,
just call one directly. Compacts the code.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Based on work done by Cyrill Corcunov (many thanks for that).
In this commit we implement c/r for files which have opened
/proc/$pid/ns/$ids entries.
The idea is rather simple one
Checkpoint
==========
- Check if the file name is the one of known to be ns ref
- If match then write protobuf entry
Restore
=======
- Read all ns entries from the image
- When criu tries to open one we lookup over process
tree to figure out which PID should be used in path
and then just open it
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This will be needed for fast parsing of procfs ns references.
[ xemul: Add user_ns_desc here ]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is less useful than fixing typos in output messages, but anyway.
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's opened in switch_ns.
CID 996194 (#3 of 5): Resource leak (RESOURCE_LEAK)
11. leaked_handle: Handle variable rst going out of scope leaks the handle.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When we've read all pstree-items and their ids we
can get the desired clone-flags early and avoid all
these dances with flag calculations in fork_with_pid
and company.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In old images we had no clue whether the root task is to be
created in new namespaces. Remember using the --namespaces
option for explicitl specification of this fact.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's no longer required to use this option -- two currently
supported cases (tasks on host and tasks in containers) can
be detected automatically. Keep this option for future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Introduce the current_ns_mask variable, that collects info about
which namespaces tasks being dumped and to be restored live in.
For simlicity all tasks are supposed to live in one set of spaces.
This should be fixed eventually.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
