Here is a problem with ghost files. Links are created on restore, but
they can't be created on any mount point, because a mount point can be
non-root bind-mount of another one. So we need to find the root mount
and create all links there.
v2: clean up
v3: add optimization for the case when both links on the same mount
point.
v4: don't look up mount points by mnt_id in a second time.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
If we have opened and rmdir-ed directory, the dump works OK
creating the ghost file and remap, but restore creates _file_
instead of directory.
Fix this.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
When opening a reg file on restore -- check that the file size we
opened matches the on we saw on dump. This is not bullet-proof protection,
but is helpful to protect against FS updates between dump/restore.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This fixes the support for fifo-s in mount namespaces and
makes it easier to control the correct open_path() usage in
the future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Same for previous patch with vmas -- we do it on collect and
on real open. Just put the pointer on fifo_info structure.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We do it first -- on collect, second -- on restore. The
2nd lookup is excessive, we can put fd pointer on vm_area
at lookup and reuse one later.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
If a file mmaped or pointed by exe link is unlinked, we will
generate a ghost file for it. On restore the ghost file will
be created with the users counter 1 and the very first open
(e.g. for mmap) will unlink the file.
Handle this by bumping up user counter for every mapping
pointing on the file.
This appeared after previous patches that packed the reg-files
image. Before it each vma and exe link created separate entry
in the reg-files image.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In case if checkpoint is failed or -R option passed
we need to remove link remap files created during
dump procedure.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
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>
No need to walk up the directories if we need
to include protobuf file. This was always a bad
use of ability to walk the filesystem from other
headers.
Same time we don't need -I$(SRC_DIR)/protobuf/
in general makefile anymore.
[xemul: Small fixlet in head Makefile, since patch
it out-of-order]
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Currently fdinfo dumps for each task, so CR_FD_FDINFO is in cr_fdset.
A few tasks can share one fd table and the set of descriptors will be
dumped once and a image name will contain files_id instead of pid.
In this case CR_FD_FDINFO will go away from cr_fdset.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
* The following files goes into the directory arch/x86/include/asm unmodified:
- include/atomic.h,
- include/linkage.h,
- include/memcpy_64.h,
- include/types.h,
- include/bitops.h,
- pie/parasite-head-x86-64.S,
- include/processor-flags.h,
- include/syscall-x86-64.def.
* Changed include directives in the source files that include the headers
listed above.
* Modified build scripts to reflect the source moves.
Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Make them look like __CR_<smth>_H__ with
sed -e '1,2s/#\(ifndef\|define\) _\?_\?\(CR_\)\?/#\1 __CR_/' -e '1,2s/_H_\?_\?.*$/_H__/'
on every header file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The remap_put will be needed to defer unlinking of ghost files
if they are referred from inotify system.
The lookup_remap is needed to figure out if the watch
target the inotify has present in ghost files list.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
For linked remaps we'll use similar technique as for ghost
files, but lighter. For that sake make reg_file_info remap
to file_remap, not to the whole host_file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Otherwise there is a race between files with same names:
link(name -> ghost) link(name->ghost)
open(name)
unlink(name)
open(name) -> ENOENT
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
A ghost file is used for restoring descriptors of an unlinked file.
It is created, opened and deleted.
Currently ghost files are collected in root task and then removed
by crtools when everybody is restored. This scheme doesn't work,
ghost_file_list is not shared, plus tasks may live in different mount
namespace.
It was broken by the following commit:
bd4e5d2f restore: prepare shared objects after initializing namespaces
We can't just move clear_ghost_files(), because we need to wait, until
all processes have not opened a ghost file.
We can add one more global barrier or move clear_ghost_files() in
a restore code bellow an existent barrier.
Here is a better sollution, a gost file is deleted by the last user.
v2: Use the type atomic_t and fix a commit message.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This patch switches reg_file_entry structure with RegFileEntry
protobuf entry. Note that there a few nits remains
- old fown_t structure doesn't scale well with FownEntry from
RegFileEntry, so to not mess with rest of crtools code
I've added a couple of opencoded copy operands, will clean
this aspect up once rest of code is converted
- the "show" procedure doesn't print fown for same reason
v2:
- rename fown_t to fown_entry in .proto
v3:
- don't print nil symbol on show
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Don't push open cb onto reg_file_into, pass it into regfiles engine
as an argument.
Note: I haven't merged the fifo zdtms yet, thus this patch is untested.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Checkpoint and restore of fifo is similar to
pipes c/r except the pipe end-points are named
file.
Because the fifo has a name we use regular files
facility for fifo path c/r.
Still there is a trick used to "open" fifo:
the opening procedure migh sleep if a fifo's peer
is not yet opened, so before doing a real open
we yield a fake open procedure (with O_RDWR flag)
which prevents us from sleeping even if peer
is not yet ready. Also we need writable fifo
end to restore data queued.
v2:
- add open/priv members to reg_file_info
- make open_fifo_fd to use open_fe_fd
- comment on pipe_id
- make sure the fifo data is not restored twice
v3:
- drop useless fixme comment and add sane one
v4:
- Use restore_data flag to escape data restore duplication
- Use S_ISREG for file contents copying
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Instead of spreading regular files handling code over
files.c and cr-dump.c move it to files-reg.c.
This allows to extend regular file handling code in
future without disturbing other source files and
make code logically coupled, where files.c is mostly
a place for general file handling code unrelated to
file type specifics.
While mostly it was code tossing there is some change
I have to notice -- the structure ghost_file was previously
declared in two paces cr-dump.c and files.c, in cr-dump.c
it was used for dumping while in files.c it was used
for restore. The structure had different members.
So to resolve this conflict the ghost_file structure
was renamed to ghost_file_dumpee.
Nothing else is changed.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
