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>
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>
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>
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>
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>
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>
Since now we have local copies of a remove FDs we can dump socket queus without entering
a parasite code. This makes the code MUCH simpler.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
We have two checks for fd being a chrdev:
One to skip stdio-s that are termilans and
The other one for any fd being a /dev/null or other special device.
Clean this a little bit.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The statfs is not required, we now check for fd being a socket with S_IFSOCK.
The 2nd stat is just not needed, the caller provides stat info.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This structure is actualy an fd parameter, so put it there. This will also
help with future patching.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Since we're able to simply drain file descriptors
we're interested in, just do that with parasite
help.
This changes the calling sequence a bit
1) Collect file descriptors before parasite
get intected the dumpee and remember them in
local copy.
2) Ask parasite to drain collected descriptrs
into our space.
3) Operate with file descriptors directly via fcntl
calls and such.
Overall idea is to prepare ground for fowners
dumping which will be addressed in further patches.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This contains reg-files and sk-queues images, as they contain data
which is potentially generated by every task, so keep it open all
the time dump goes.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Write two helpers for opening an fdset for task and one for ns.
This probably can be done with some "generic" macro(s), but this
time it's simpler not to produce more code of that type.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
It's not required any longer. Now fdsets are allocated one-by-one only
when required and there's no need in adding new fds to existing sets.
Thus just remove the last arg from cr_fdset_open.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Move the fdset allocation inside dump_one_task and do it only for
non-zombies.
This makes sure we don't need to re-use an fdset, since we do allocate
it only when required.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This fd is global, so make it such. It will stop being just a global
variable soon.
Plus, remove the pid arg from format.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This routine is used for dumping tasks, threads and zombies. For the
last two the whole fdset is not allocated thus it will be better to
use single fd in this case.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Pid number is redundant - this file is one for the whole tree.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Since now on the fdinfo image only contains plain fdinfo_entry-es.
The tpye == FDINFO_REG files are described by regfiles.img entries
and are matched by te ID in both.
At dump stage each new ID generated results in a new entry in the
regfiles.img. At restore stage open_fe_fd should open a regfile by
the fdinfo's ID. Now this is done in suboptimal way, need to improve.
Show shows both images separately.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Make fdinfo_entry carry only the minimal info describing a file
descriptor -- the fd value itself, the fd type (regular file, exe
link, cwd, filemap and it will be pipes, sockets, inotifies, etc.)
and the describing file ID.
The mentioned ID will identify the type-d object, e.g. for regfiles
this ID is already generated with file-ids.c code.
The other part of this structure describes a regfile (i.e. a file
opened with open syscall). I put this new entry at the end of the
fdinfo_entry just to make the patching simpler. Soon this entry
will be dumped into its own file.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The unique id is 32 bit and consists only of the subid value. This
is _really_ enough. The genid part is just a hint for the tree-search
algirythm to avoid unneeded sys_kcmp calls.
Plus, generate IDs for special files. This will make it easier to
move the regfiles into into separate files (see the respective patch
for details).
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Hide the structure - it's not required.
[ xemul: Ranem long id into u32 id and adopt to current tree ]
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This is a cleanup patch. This tree is merged only once. So it's image file can
be opened by opne_image() call and dumped right after collect stage.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
The core image now contains only core per-task stuff.
The new file resurrects Tula magic number removed earlier.
Acked-by: Andrey Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
