Our loggin engine prints file:line only at invoke point,
so it's unable to see where exactly reopen_fd_as_safe is
failed.
With this patch the output is more human readable
| Error (util.c:96): fd 7 already in use (called at files.c:359)
Ideally we need full backtrace here, but it's different task.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Completely unlinked file is the one with n_link count being zero.
Such files only allow to read their contents and carry with us.
In order to dump this thing I introduce the "path remap" technology.
For reg file a remapping entry is dumped which describes, that at
restore stage before opening a regfile->path this path should be
linked to some other name and then (after open) unlinked.
For completely unlinked files the remap path would be a path to
a "ghost" file, i.e. a file which is created only at the time of
restore and which is removed completely at the end of it.
Partially unlinked files (i.e. those having n_link != 0, but a
path by which we see them in someone's fd is not accessible) should
be handled in another way.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The base idea is trivial, once file descriptor
created the owner is read and set up.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Just show implemented and stubs added to image
(regular file and pipes).
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
I store them on _entry since sids can only be inherited or
set to current's pid. Thus the best we can do it restore sids
at fork time, thus save them in the image we use to fork.
Maybe when we submit patches that will give us ability to set
arbitrary pgid and sid we'll change this, but this is in the
future.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
They are just two next in this file, so extend. This is
required for pgid/sid early read, see next patches for
details.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is trivial change, but is required to check for pgid/sid
are in 'restorable' state, see for respective patch/code for
details.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
New stage CR_STATE_FORKING. This is required to restore pgids
properly -- we need to make sure a task with pid whose pgid we
are about to enter is alive. And this task is not necesserily
our parent, thus wait for everyone to appear.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
For regfiles this is done at open() time, for pipes thit is done with fcntl. Use
the same fcntl approach for sockets.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This bit is not per-file, but per-fd, thus put it on the fdinfo_entry.
Draing these bits from parasite together with the fds themselves, save
into image and restore with fcntl F_SETFD cmd where applicable.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The flags are only one bit in the kernel (close-on-exec, all the rest are not per-fd, but per-file),
but for simplicity I save it in a char field.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It used to be ulong, but it can be int now (no mapping addresses there). And the
name fd is better than fd_name (reason is the same).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Just dump their IDs and check they are not shared. For future.
IO and SEMUNDO is not there since tasks may have NO such objects
and currently we cannot detect whether they have them equal or
both don't have.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Just move the patched code from file-ids.c to kcmp-ids.c and
make the former one be client for the latter.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Now we store only real fdtable entries in this file, so it's
time to name the field properly and change type to u32.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The mm_xxx bits are per-mm_struct, not per-task_struct in kernel.
Thus, when we support CLONE_VM we'd better have these bits in a
separate image file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
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 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 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>
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>
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>
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>
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>
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>
Since proc_parse.h declares functions which have
list_head as arguments, it should include list.h
and basic types.
Otherwise if included into the files without list support
the compilation might fail as
|
| In file included from cr-check.c:5:
| ./include/proc_parse.h:83: error: expected declaration specifiers or ‘...’ before ‘bool’
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
In commit 71cc2733a7
I occasionally dropped the ability to abort on waiting
(because we used signed -1 value to inform waiters that
something is wrong and waiting should be aborted, but
the type was changed to unsigned one and as result
this condition never triggers).
So to resolve it futex_abort_and_wake() is added and
should be used explicitly where appropriate instead
if signess hack.
Reported-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrew Vagin <avagin@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This was required when pages were stored in elf files for
exec. Now we can stop reading it on eof.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The list_head ptr passed into it can be converted into
the respective _info with container_of, rather than search.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Now fdinfos are collected independently from reg files and
sockets. During tihs collect we effectively create the mirroring
list of both by checking which type-IDs are added first.
Fix this by removing the fdinfo_desc and attaching fds directly
to collected reg files and sockets. Pipes and unix sockets will
be reworked in the same manner soon.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
