Based on xemul@ patches.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This patch was designed to be generic and thus usable for all kinds of
sockets. Not sure, thah this goal has been reached, but at least I tried.
Key ideas:
1) On-stack structure for collecting sockets queues and then passing them to
parasite code.
2) Singly linked list is used for collecting structures, representing sockets
of any kind (!) with queues.
Based on xemul@ patches.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This patch adds sockets queue dump functionality. Key ideas
1) sockets info is passed as plain array in parasite args.
2) new socket option SO_PEEK_OFF with MSG_PEEK is used to read the get the
queue's packets.
3) Buffer for packet will be allocated for each socket separately and with
size of socket sending buffer. For stream sockets is means, that it's queue
will be dumped in chunks of this size.
Note: loop around sys_msgrcv() is required for DGRAM sockets - sys_msgrcv()
with MSG_PEEK will return only one packet.
Based on xemul@ patches.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
* @xemul:
crtools: Collect dumping fd parameters into one place
crtools: Toss dump_one_fd args around
crtools: Rename fd to lfd in dump_one_fd
crtools: Sanitize pstree construction
crtools: Remove unused printk_registers and co
crtools: Deduplicate file info showing code
crtools: Merge pstree collecting into showing
crtools: Remove unused and wrong arrays from pstree image
crtools: Remove lseeks after prep_cr_ calls
crtools: Cleanup collect_pstree in cr-show
Conflicts:
cr-dump.c
include/sockets.h
sockets.c
The conflicts are mostly because of commit
995ef5eca3
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
This allows us to get rid of open-coded "/proc/pid/X".
Based-on-patch-from: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Make the dump_one_fd fn accept local fd and integer target fd values
instead of target fd dir and target fd string name.
This saves couple of atoi-s (done once) and makes the next patch simpler.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Remove unneeded path argument (we do know the file data is read from) and
actually bogus show_header boolean.
Also introduce two helpers for showing header and tail.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Since we're not system library
- no underscopes in functions name until really needed
and known to not clash with posix namespace
- empty line between system headers and own headers
for readability
- extern for function prototypes
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Currently it can only work with stream sockets, which have no skbs in queues
(listening or established -- both work OK).
The cpt part uses the sock_diag engine that was merged to Dave recently to
collect sockets. Then it dumps sockets by checking the filesystem ID of a
failed-to-open through /proc/pid/fd descriptors (sockets do not allow for
such tricks with opens through proc) against SOCKFS_TYPE.
The rst part is more tricky. Listen sockets are just restored, this is simple.
Connected sockets are restored like this:
1. One end establishes a listening anon socket at the desired descriptor;
2. The other end just creates a socket at the desired descriptor;
3. All sockets, that are to be connect()-ed call connect. Unix sockets
do not block connect() till the accept() time and thus we continue with...
4. ... all listening sockets call accept() and ... dup2 the new fd into the
accepting end.
There's a problem with this approach -- socket names are not preserved, but
looking into our OpenVZ implementation I think this is OK for existing apps.
What should be done next is:
1. Need to merge the file IDs patches in our tree and make Andrey to
support files sharing. This will solve the
sk = socket();
fork();
case. Currently it simply doesn't work :(
2. Need to add support for DGRAM sockets -- I wrote comment how to do it
in the can_dump_unix_sk()
3. Need to add support for in-flight connections
4. Implement support for UDP sockets (quite simple)
5. Implement support for listening TCP sockets (also not very complex)
6. Implement support for connected TCP scokets (hard one, Tejun's patches are not
very good for this from my POV)
Cyrill, plz, apply this patch and put the above descriptions onto wiki docs (do we
have the plans page yet?).
Andrey, plz, take care of unix sockets tests in zdtm. Most likely it won't work till
you do the shared files support for sockets.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
