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Commit Graph

102 Commits

Author SHA1 Message Date
Taehee Yoo
9cf1cd8ee3 tipc: fix ordering of tipc module init and exit routine
In order to set/get/dump, the tipc uses the generic netlink
infrastructure. So, when tipc module is inserted, init function
calls genl_register_family().
After genl_register_family(), set/get/dump commands are immediately
allowed and these callbacks internally use the net_generic.
net_generic is allocated by register_pernet_device() but this
is called after genl_register_family() in the __init function.
So, these callbacks would use un-initialized net_generic.

Test commands:
    #SHELL1
    while :
    do
        modprobe tipc
        modprobe -rv tipc
    done

    #SHELL2
    while :
    do
        tipc link list
    done

Splat looks like:
[   59.616322][ T2788] kasan: CONFIG_KASAN_INLINE enabled
[   59.617234][ T2788] kasan: GPF could be caused by NULL-ptr deref or user memory access
[   59.618398][ T2788] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[   59.619389][ T2788] CPU: 3 PID: 2788 Comm: tipc Not tainted 5.4.0+ #194
[   59.620231][ T2788] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   59.621428][ T2788] RIP: 0010:tipc_bcast_get_broadcast_mode+0x131/0x310 [tipc]
[   59.622379][ T2788] Code: c7 c6 ef 8b 38 c0 65 ff 0d 84 83 c9 3f e8 d7 a5 f2 e3 48 8d bb 38 11 00 00 48 b8 00 00 00 00
[   59.622550][ T2780] NET: Registered protocol family 30
[   59.624627][ T2788] RSP: 0018:ffff88804b09f578 EFLAGS: 00010202
[   59.624630][ T2788] RAX: dffffc0000000000 RBX: 0000000000000011 RCX: 000000008bc66907
[   59.624631][ T2788] RDX: 0000000000000229 RSI: 000000004b3cf4cc RDI: 0000000000001149
[   59.624633][ T2788] RBP: ffff88804b09f588 R08: 0000000000000003 R09: fffffbfff4fb3df1
[   59.624635][ T2788] R10: fffffbfff50318f8 R11: ffff888066cadc18 R12: ffffffffa6cc2f40
[   59.624637][ T2788] R13: 1ffff11009613eba R14: ffff8880662e9328 R15: ffff8880662e9328
[   59.624639][ T2788] FS:  00007f57d8f7b740(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000
[   59.624645][ T2788] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   59.625875][ T2780] tipc: Started in single node mode
[   59.626128][ T2788] CR2: 00007f57d887a8c0 CR3: 000000004b140002 CR4: 00000000000606e0
[   59.633991][ T2788] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   59.635195][ T2788] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   59.636478][ T2788] Call Trace:
[   59.637025][ T2788]  tipc_nl_add_bc_link+0x179/0x1470 [tipc]
[   59.638219][ T2788]  ? lock_downgrade+0x6e0/0x6e0
[   59.638923][ T2788]  ? __tipc_nl_add_link+0xf90/0xf90 [tipc]
[   59.639533][ T2788]  ? tipc_nl_node_dump_link+0x318/0xa50 [tipc]
[   59.640160][ T2788]  ? mutex_lock_io_nested+0x1380/0x1380
[   59.640746][ T2788]  tipc_nl_node_dump_link+0x4fd/0xa50 [tipc]
[   59.641356][ T2788]  ? tipc_nl_node_reset_link_stats+0x340/0x340 [tipc]
[   59.642088][ T2788]  ? __skb_ext_del+0x270/0x270
[   59.642594][ T2788]  genl_lock_dumpit+0x85/0xb0
[   59.643050][ T2788]  netlink_dump+0x49c/0xed0
[   59.643529][ T2788]  ? __netlink_sendskb+0xc0/0xc0
[   59.644044][ T2788]  ? __netlink_dump_start+0x190/0x800
[   59.644617][ T2788]  ? __mutex_unlock_slowpath+0xd0/0x670
[   59.645177][ T2788]  __netlink_dump_start+0x5a0/0x800
[   59.645692][ T2788]  genl_rcv_msg+0xa75/0xe90
[   59.646144][ T2788]  ? __lock_acquire+0xdfe/0x3de0
[   59.646692][ T2788]  ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[   59.647340][ T2788]  ? genl_lock_dumpit+0xb0/0xb0
[   59.647821][ T2788]  ? genl_unlock+0x20/0x20
[   59.648290][ T2788]  ? genl_parallel_done+0xe0/0xe0
[   59.648787][ T2788]  ? find_held_lock+0x39/0x1d0
[   59.649276][ T2788]  ? genl_rcv+0x15/0x40
[   59.649722][ T2788]  ? lock_contended+0xcd0/0xcd0
[   59.650296][ T2788]  netlink_rcv_skb+0x121/0x350
[   59.650828][ T2788]  ? genl_family_rcv_msg_attrs_parse+0x320/0x320
[   59.651491][ T2788]  ? netlink_ack+0x940/0x940
[   59.651953][ T2788]  ? lock_acquire+0x164/0x3b0
[   59.652449][ T2788]  genl_rcv+0x24/0x40
[   59.652841][ T2788]  netlink_unicast+0x421/0x600
[ ... ]

Fixes: 7e43690578 ("tipc: fix a slab object leak")
Fixes: a62fbccecd ("tipc: make subscriber server support net namespace")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-06 12:01:09 -08:00
David S. Miller
19b7e21c55 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Lots of overlapping changes and parallel additions, stuff
like that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-16 21:51:42 -08:00
Matt Bennett
d7f9f47d4d tipc: add back tipc prefix to log messages
The tipc prefix for log messages generated by tipc was
removed in commit 07f6c4bc04 ("tipc: convert tipc reference
table to use generic rhashtable").

This is still a useful prefix so add it back.

Signed-off-by: Matt Bennett <matt.bennett@alliedtelesis.co.nz>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:03:03 -08:00
Tuong Lien
fc1b6d6de2 tipc: introduce TIPC encryption & authentication
This commit offers an option to encrypt and authenticate all messaging,
including the neighbor discovery messages. The currently most advanced
algorithm supported is the AEAD AES-GCM (like IPSec or TLS). All
encryption/decryption is done at the bearer layer, just before leaving
or after entering TIPC.

Supported features:
- Encryption & authentication of all TIPC messages (header + data);
- Two symmetric-key modes: Cluster and Per-node;
- Automatic key switching;
- Key-expired revoking (sequence number wrapped);
- Lock-free encryption/decryption (RCU);
- Asynchronous crypto, Intel AES-NI supported;
- Multiple cipher transforms;
- Logs & statistics;

Two key modes:
- Cluster key mode: One single key is used for both TX & RX in all
nodes in the cluster.
- Per-node key mode: Each nodes in the cluster has one specific TX key.
For RX, a node requires its peers' TX key to be able to decrypt the
messages from those peers.

Key setting from user-space is performed via netlink by a user program
(e.g. the iproute2 'tipc' tool).

Internal key state machine:

                                 Attach    Align(RX)
                                     +-+   +-+
                                     | V   | V
        +---------+      Attach     +---------+
        |  IDLE   |---------------->| PENDING |(user = 0)
        +---------+                 +---------+
           A   A                   Switch|  A
           |   |                         |  |
           |   | Free(switch/revoked)    |  |
     (Free)|   +----------------------+  |  |Timeout
           |              (TX)        |  |  |(RX)
           |                          |  |  |
           |                          |  v  |
        +---------+      Switch     +---------+
        | PASSIVE |<----------------| ACTIVE  |
        +---------+       (RX)      +---------+
        (user = 1)                  (user >= 1)

The number of TFMs is 10 by default and can be changed via the procfs
'net/tipc/max_tfms'. At this moment, as for simplicity, this file is
also used to print the crypto statistics at runtime:

echo 0xfff1 > /proc/sys/net/tipc/max_tfms

The patch defines a new TIPC version (v7) for the encryption message (-
backward compatibility as well). The message is basically encapsulated
as follows:

   +----------------------------------------------------------+
   | TIPCv7 encryption  | Original TIPCv2    | Authentication |
   | header             | packet (encrypted) | Tag            |
   +----------------------------------------------------------+

The throughput is about ~40% for small messages (compared with non-
encryption) and ~9% for large messages. With the support from hardware
crypto i.e. the Intel AES-NI CPU instructions, the throughput increases
upto ~85% for small messages and ~55% for large messages.

By default, the new feature is inactive (i.e. no encryption) until user
sets a key for TIPC. There is however also a new option - "TIPC_CRYPTO"
in the kernel configuration to enable/disable the new code when needed.

MAINTAINERS | add two new files 'crypto.h' & 'crypto.c' in tipc

Acked-by: Ying Xue <ying.xue@windreiver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-08 14:01:59 -08:00
Hoang Le
f73b12812a tipc: improve throughput between nodes in netns
Currently, TIPC transports intra-node user data messages directly
socket to socket, hence shortcutting all the lower layers of the
communication stack. This gives TIPC very good intra node performance,
both regarding throughput and latency.

We now introduce a similar mechanism for TIPC data traffic across
network namespaces located in the same kernel. On the send path, the
call chain is as always accompanied by the sending node's network name
space pointer. However, once we have reliably established that the
receiving node is represented by a namespace on the same host, we just
replace the namespace pointer with the receiving node/namespace's
ditto, and follow the regular socket receive patch though the receiving
node. This technique gives us a throughput similar to the node internal
throughput, several times larger than if we let the traffic go though
the full network stacks. As a comparison, max throughput for 64k
messages is four times larger than TCP throughput for the same type of
traffic.

To meet any security concerns, the following should be noted.

- All nodes joining a cluster are supposed to have been be certified
and authenticated by mechanisms outside TIPC. This is no different for
nodes/namespaces on the same host; they have to auto discover each
other using the attached interfaces, and establish links which are
supervised via the regular link monitoring mechanism. Hence, a kernel
local node has no other way to join a cluster than any other node, and
have to obey to policies set in the IP or device layers of the stack.

- Only when a sender has established with 100% certainty that the peer
node is located in a kernel local namespace does it choose to let user
data messages, and only those, take the crossover path to the receiving
node/namespace.

- If the receiving node/namespace is removed, its namespace pointer
is invalidated at all peer nodes, and their neighbor link monitoring
will eventually note that this node is gone.

- To ensure the "100% certainty" criteria, and prevent any possible
spoofing, received discovery messages must contain a proof that the
sender knows a common secret. We use the hash mix of the sending
node/namespace for this purpose, since it can be accessed directly by
all other namespaces in the kernel. Upon reception of a discovery
message, the receiver checks this proof against all the local
namespaces'hash_mix:es. If it finds a match, that, along with a
matching node id and cluster id, this is deemed sufficient proof that
the peer node in question is in a local namespace, and a wormhole can
be opened.

- We should also consider that TIPC is intended to be a cluster local
IPC mechanism (just like e.g. UNIX sockets) rather than a network
protocol, and hence we think it can justified to allow it to shortcut the
lower protocol layers.

Regarding traceability, we should notice that since commit 6c9081a391
("tipc: add loopback device tracking") it is possible to follow the node
internal packet flow by just activating tcpdump on the loopback
interface. This will be true even for this mechanism; by activating
tcpdump on the involved nodes' loopback interfaces their inter-name
space messaging can easily be tracked.

v2:
- update 'net' pointer when node left/rejoined
v3:
- grab read/write lock when using node ref obj
v4:
- clone traffics between netns to loopback

Suggested-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-29 17:55:38 -07:00
John Rutherford
6c9081a391 tipc: add loopback device tracking
Since node internal messages are passed directly to the socket, it is not
possible to observe those messages via tcpdump or wireshark.

We now remedy this by making it possible to clone such messages and send
the clones to the loopback interface.  The clones are dropped at reception
and have no functional role except making the traffic visible.

The feature is enabled if network taps are active for the loopback device.
pcap filtering restrictions require the messages to be presented to the
receiving side of the loopback device.

v3 - Function dev_nit_active used to check for network taps.
   - Procedure netif_rx_ni used to send cloned messages to loopback device.

Signed-off-by: John Rutherford <john.rutherford@dektech.com.au>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-08 22:11:39 -07:00
Xin Long
c492d4c74d tipc: change to use register_pernet_device
This patch is to fix a dst defcnt leak, which can be reproduced by doing:

  # ip net a c; ip net a s; modprobe tipc
  # ip net e s ip l a n eth1 type veth peer n eth1 netns c
  # ip net e c ip l s lo up; ip net e c ip l s eth1 up
  # ip net e s ip l s lo up; ip net e s ip l s eth1 up
  # ip net e c ip a a 1.1.1.2/8 dev eth1
  # ip net e s ip a a 1.1.1.1/8 dev eth1
  # ip net e c tipc b e m udp n u1 localip 1.1.1.2
  # ip net e s tipc b e m udp n u1 localip 1.1.1.1
  # ip net d c; ip net d s; rmmod tipc

and it will get stuck and keep logging the error:

  unregister_netdevice: waiting for lo to become free. Usage count = 1

The cause is that a dst is held by the udp sock's sk_rx_dst set on udp rx
path with udp_early_demux == 1, and this dst (eventually holding lo dev)
can't be released as bearer's removal in tipc pernet .exit happens after
lo dev's removal, default_device pernet .exit.

 "There are two distinct types of pernet_operations recognized: subsys and
  device.  At creation all subsys init functions are called before device
  init functions, and at destruction all device exit functions are called
  before subsys exit function."

So by calling register_pernet_device instead to register tipc_net_ops, the
pernet .exit() will be invoked earlier than loopback dev's removal when a
netns is being destroyed, as fou/gue does.

Note that vxlan and geneve udp tunnels don't have this issue, as the udp
sock is released in their device ndo_stop().

This fix is also necessary for tipc dst_cache, which will hold dsts on tx
path and I will introduce in my next patch.

Reported-by: Li Shuang <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 16:51:47 -07:00
Junwei Hu
526f5b851a tipc: fix modprobe tipc failed after switch order of device registration
Error message printed:
modprobe: ERROR: could not insert 'tipc': Address family not
supported by protocol.
when modprobe tipc after the following patch: switch order of
device registration, commit 7e27e8d613
("tipc: switch order of device registration to fix a crash")

Because sock_create_kern(net, AF_TIPC, ...) called by
tipc_topsrv_create_listener() in the initialization process
of tipc_init_net(), so tipc_socket_init() must be execute before that.
Meanwhile, tipc_net_id need to be initialized when sock_create()
called, and tipc_socket_init() is no need to be called for each namespace.

I add a variable tipc_topsrv_net_ops, and split the
register_pernet_subsys() of tipc into two parts, and split
tipc_socket_init() with initialization of pernet params.

By the way, I fixed resources rollback error when tipc_bcast_init()
failed in tipc_init_net().

Fixes: 7e27e8d613 ("tipc: switch order of device registration to fix a crash")
Signed-off-by: Junwei Hu <hujunwei4@huawei.com>
Reported-by: Wang Wang <wangwang2@huawei.com>
Reported-by: syzbot+1e8114b61079bfe9cbc5@syzkaller.appspotmail.com
Reviewed-by: Kang Zhou <zhoukang7@huawei.com>
Reviewed-by: Suanming Mou <mousuanming@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-20 10:45:43 -07:00
David S. Miller
5593530e56 Revert "tipc: fix modprobe tipc failed after switch order of device registration"
This reverts commit 532b0f7ece.

More revisions coming up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-17 12:15:05 -07:00
Junwei Hu
532b0f7ece tipc: fix modprobe tipc failed after switch order of device registration
Error message printed:
modprobe: ERROR: could not insert 'tipc': Address family not
supported by protocol.
when modprobe tipc after the following patch: switch order of
device registration, commit 7e27e8d613
("tipc: switch order of device registration to fix a crash")

Because sock_create_kern(net, AF_TIPC, ...) is called by
tipc_topsrv_create_listener() in the initialization process
of tipc_net_ops, tipc_socket_init() must be execute before that.

I move tipc_socket_init() into function tipc_init_net().

Fixes: 7e27e8d613
("tipc: switch order of device registration to fix a crash")
Signed-off-by: Junwei Hu <hujunwei4@huawei.com>
Reported-by: Wang Wang <wangwang2@huawei.com>
Reviewed-by: Kang Zhou <zhoukang7@huawei.com>
Reviewed-by: Suanming Mou <mousuanming@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-17 11:33:51 -07:00
Junwei Hu
7e27e8d613 tipc: switch order of device registration to fix a crash
When tipc is loaded while many processes try to create a TIPC socket,
a crash occurs:
 PANIC: Unable to handle kernel paging request at virtual
 address "dfff20000000021d"
 pc : tipc_sk_create+0x374/0x1180 [tipc]
 lr : tipc_sk_create+0x374/0x1180 [tipc]
   Exception class = DABT (current EL), IL = 32 bits
 Call trace:
  tipc_sk_create+0x374/0x1180 [tipc]
  __sock_create+0x1cc/0x408
  __sys_socket+0xec/0x1f0
  __arm64_sys_socket+0x74/0xa8
 ...

This is due to race between sock_create and unfinished
register_pernet_device. tipc_sk_insert tries to do
"net_generic(net, tipc_net_id)".
but tipc_net_id is not initialized yet.

So switch the order of the two to close the race.

This can be reproduced with multiple processes doing socket(AF_TIPC, ...)
and one process doing module removal.

Fixes: a62fbccecd ("tipc: make subscriber server support net namespace")
Signed-off-by: Junwei Hu <hujunwei4@huawei.com>
Reported-by: Wang Wang <wangwang2@huawei.com>
Reviewed-by: Xiaogang Wang <wangxiaogang3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-16 12:25:02 -07:00
Hoang Le
ff2ebbfba6 tipc: introduce new capability flag for cluster
As a preparation for introducing a smooth switching between replicast
and broadcast method for multicast message, We have to introduce a new
capability flag TIPC_MCAST_RBCTL to handle this new feature.

During a cluster upgrade a node can come back with this new capabilities
which also must be reflected in the cluster capabilities field.
The new feature is only applicable if all node in the cluster supports
this new capability.

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-19 13:56:17 -07:00
Kirill Tkhai
2f635ceeb2 net: Drop pernet_operations::async
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27 13:18:09 -04:00
Jon Maloy
25b0b9c4e8 tipc: handle collisions of 32-bit node address hash values
When a 32-bit node address is generated from a 128-bit identifier,
there is a risk of collisions which must be discovered and handled.

We do this as follows:
- We don't apply the generated address immediately to the node, but do
  instead initiate a 1 sec trial period to allow other cluster members
  to discover and handle such collisions.

- During the trial period the node periodically sends out a new type
  of message, DSC_TRIAL_MSG, using broadcast or emulated broadcast,
  to all the other nodes in the cluster.

- When a node is receiving such a message, it must check that the
  presented 32-bit identifier either is unused, or was used by the very
  same peer in a previous session. In both cases it accepts the request
  by not responding to it.

- If it finds that the same node has been up before using a different
  address, it responds with a DSC_TRIAL_FAIL_MSG containing that
  address.

- If it finds that the address has already been taken by some other
  node, it generates a new, unused address and returns it to the
  requester.

- During the trial period the requesting node must always be prepared
  to accept a failure message, i.e., a message where a peer suggests a
  different (or equal)  address to the one tried. In those cases it
  must apply the suggested value as trial address and restart the trial
  period.

This algorithm ensures that in the vast majority of cases a node will
have the same address before and after a reboot. If a legacy user
configures the address explicitly, there will be no trial period and
messages, so this protocol addition is completely backwards compatible.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 13:12:18 -04:00
Jon Maloy
d50ccc2d39 tipc: add 128-bit node identifier
We add a 128-bit node identity, as an alternative to the currently used
32-bit node address.

For the sake of compatibility and to minimize message header changes
we retain the existing 32-bit address field. When not set explicitly by
the user, this field will be filled with a hash value generated from the
much longer node identity, and be used as a shorthand value for the
latter.

We permit either the address or the identity to be set by configuration,
but not both, so when the address value is set by a legacy user the
corresponding 128-bit node identity is generated based on the that value.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 13:12:18 -04:00
Kirill Tkhai
afbbc374ab net: Convert tipc_net_ops
TIPC looks concentrated in itself, and other pernet_operations
seem not touching its entities.

tipc_net_ops look pernet-divided, and they should be safe to
be executed in parallel for several net the same time.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-13 11:24:56 -04:00
Alexey Dobriyan
c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Jon Paul Maloy
35c55c9877 tipc: add neighbor monitoring framework
TIPC based clusters are by default set up with full-mesh link
connectivity between all nodes. Those links are expected to provide
a short failure detection time, by default set to 1500 ms. Because
of this, the background load for neighbor monitoring in an N-node
cluster increases with a factor N on each node, while the overall
monitoring traffic through the network infrastructure increases at
a ~(N * (N - 1)) rate. Experience has shown that such clusters don't
scale well beyond ~100 nodes unless we significantly increase failure
discovery tolerance.

This commit introduces a framework and an algorithm that drastically
reduces this background load, while basically maintaining the original
failure detection times across the whole cluster. Using this algorithm,
background load will now grow at a rate of ~(2 * sqrt(N)) per node, and
at ~(2 * N * sqrt(N)) in traffic overhead. As an example, each node will
now have to actively monitor 38 neighbors in a 400-node cluster, instead
of as before 399.

This "Overlapping Ring Supervision Algorithm" is completely distributed
and employs no centralized or coordinated state. It goes as follows:

- Each node makes up a linearly ascending, circular list of all its N
  known neighbors, based on their TIPC node identity. This algorithm
  must be the same on all nodes.

- The node then selects the next M = sqrt(N) - 1 nodes downstream from
  itself in the list, and chooses to actively monitor those. This is
  called its "local monitoring domain".

- It creates a domain record describing the monitoring domain, and
  piggy-backs this in the data area of all neighbor monitoring messages
  (LINK_PROTOCOL/STATE) leaving that node. This means that all nodes in
  the cluster eventually (default within 400 ms) will learn about
  its monitoring domain.

- Whenever a node discovers a change in its local domain, e.g., a node
  has been added or has gone down, it creates and sends out a new
  version of its node record to inform all neighbors about the change.

- A node receiving a domain record from anybody outside its local domain
  matches this against its own list (which may not look the same), and
  chooses to not actively monitor those members of the received domain
  record that are also present in its own list. Instead, it relies on
  indications from the direct monitoring nodes if an indirectly
  monitored node has gone up or down. If a node is indicated lost, the
  receiving node temporarily activates its own direct monitoring towards
  that node in order to confirm, or not, that it is actually gone.

- Since each node is actively monitoring sqrt(N) downstream neighbors,
  each node is also actively monitored by the same number of upstream
  neighbors. This means that all non-direct monitoring nodes normally
  will receive sqrt(N) indications that a node is gone.

- A major drawback with ring monitoring is how it handles failures that
  cause massive network partitionings. If both a lost node and all its
  direct monitoring neighbors are inside the lost partition, the nodes in
  the remaining partition will never receive indications about the loss.
  To overcome this, each node also chooses to actively monitor some
  nodes outside its local domain. Those nodes are called remote domain
  "heads", and are selected in such a way that no node in the cluster
  will be more than two direct monitoring hops away. Because of this,
  each node, apart from monitoring the member of its local domain, will
  also typically monitor sqrt(N) remote head nodes.

- As an optimization, local list status, domain status and domain
  records are marked with a generation number. This saves senders from
  unnecessarily conveying  unaltered domain records, and receivers from
  performing unneeded re-adaptations of their node monitoring list, such
  as re-assigning domain heads.

- As a measure of caution we have added the possibility to disable the
  new algorithm through configuration. We do this by keeping a threshold
  value for the cluster size; a cluster that grows beyond this value
  will switch from full-mesh to ring monitoring, and vice versa when
  it shrinks below the value. This means that if the threshold is set to
  a value larger than any anticipated cluster size (default size is 32)
  the new algorithm is effectively disabled. A patch set for altering the
  threshold value and for listing the table contents will follow shortly.

- This change is fully backwards compatible.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-15 14:06:28 -07:00
Jon Paul Maloy
10724cc7bb tipc: redesign connection-level flow control
There are two flow control mechanisms in TIPC; one at link level that
handles network congestion, burst control, and retransmission, and one
at connection level which' only remaining task is to prevent overflow
in the receiving socket buffer. In TIPC, the latter task has to be
solved end-to-end because messages can not be thrown away once they
have been accepted and delivered upwards from the link layer, i.e, we
can never permit the receive buffer to overflow.

Currently, this algorithm is message based. A counter in the receiving
socket keeps track of number of consumed messages, and sends a dedicated
acknowledge message back to the sender for each 256 consumed message.
A counter at the sending end keeps track of the sent, not yet
acknowledged messages, and blocks the sender if this number ever reaches
512 unacknowledged messages. When the missing acknowledge arrives, the
socket is then woken up for renewed transmission. This works well for
keeping the message flow running, as it almost never happens that a
sender socket is blocked this way.

A problem with the current mechanism is that it potentially is very
memory consuming. Since we don't distinguish between small and large
messages, we have to dimension the socket receive buffer according
to a worst-case of both. I.e., the window size must be chosen large
enough to sustain a reasonable throughput even for the smallest
messages, while we must still consider a scenario where all messages
are of maximum size. Hence, the current fix window size of 512 messages
and a maximum message size of 66k results in a receive buffer of 66 MB
when truesize(66k) = 131k is taken into account. It is possible to do
much better.

This commit introduces an algorithm where we instead use 1024-byte
blocks as base unit. This unit, always rounded upwards from the
actual message size, is used when we advertise windows as well as when
we count and acknowledge transmitted data. The advertised window is
based on the configured receive buffer size in such a way that even
the worst-case truesize/msgsize ratio always is covered. Since the
smallest possible message size (from a flow control viewpoint) now is
1024 bytes, we can safely assume this ratio to be less than four, which
is the value we are now using.

This way, we have been able to reduce the default receive buffer size
from 66 MB to 2 MB with maintained performance.

In order to keep this solution backwards compatible, we introduce a
new capability bit in the discovery protocol, and use this throughout
the message sending/reception path to always select the right unit.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-03 15:51:16 -04:00
Erik Hugne
541726abe7 tipc: make dist queue pernet
Nametable updates received from the network that cannot be applied
immediately are placed on a defer queue. This queue is global to the
TIPC module, which might cause problems when using TIPC in containers.
To prevent nametable updates from escaping into the wrong namespace,
we make the queue pernet instead.

Signed-off-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-11 15:22:20 -04:00
Jon Paul Maloy
5fd9fd6351 tipc: create broadcast transmission link at namespace init
The broadcast transmission link is currently instantiated when the
network subsystem is started, i.e., on order from user space via netlink.

This forces the broadcast transmission code to do unnecessary tests for
the existence of the transmission link, as well in single mode node as
in network mode.

In this commit, we do instead create the link during initialization of
the name space, and remove it when it is stopped. The fact that the
transmission link now has a guaranteed longer life cycle than any of its
potential clients paves the way for further code simplifcations
and optimizations.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24 06:56:27 -07:00
Ying Xue
57f1d1868f tipc: rename functions defined in subscr.c
When a topology server accepts a connection request from its client,
it allocates a connection instance and a tipc_subscriber structure
object. The former is used to communicate with client, and the latter
is often treated as a subscriber which manages all subscription events
requested from a same client. When a topology server receives a request
of subscribing name services from a client through the connection, it
creates a tipc_subscription structure instance which is seen as a
subscription recording what name services are subscribed. In order to
manage all subscriptions from a same client, topology server links
them into the subscrp_list of the subscriber. So subscriber and
subscription completely represents different meanings respectively,
but function names associated with them make us so confused that we
are unable to easily tell which function is against subscriber and
which is to subscription. So we want to eliminate the confusion by
renaming them.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04 15:04:00 -04:00
Ying Xue
7e43690578 tipc: fix a slab object leak
When remove TIPC module, there is a warning to remind us that a slab
object is leaked like:

root@localhost:~# rmmod tipc
[   19.056226] =============================================================================
[   19.057549] BUG TIPC (Not tainted): Objects remaining in TIPC on kmem_cache_close()
[   19.058736] -----------------------------------------------------------------------------
[   19.058736]
[   19.060287] INFO: Slab 0xffffea0000519a00 objects=23 used=1 fp=0xffff880014668b00 flags=0x100000000004080
[   19.061915] INFO: Object 0xffff880014668000 @offset=0
[   19.062717] kmem_cache_destroy TIPC: Slab cache still has objects

This is because the listening socket of TIPC topology server is not
closed before TIPC proto handler is unregistered with proto_unregister().
However, as the socket is closed in tipc_exit_net() which is called by
unregister_pernet_subsys() during unregistering TIPC namespace operation,
the warning can be eliminated if calling unregister_pernet_subsys() is
moved before calling proto_unregister().

Fixes: e05b31f4bf ("tipc: make tipc socket support net namespace")
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 23:10:08 -04:00
Richard Alpe
22ae7cff50 tipc: nl compat add noop and remove legacy nl framework
Add TIPC_CMD_NOOP to compat layer and remove the old framework.

All legacy nl commands are now converted to the compat layer in
netlink_compat.c.

Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-09 13:20:49 -08:00
Richard Alpe
bfb3e5dd8d tipc: move and rename the legacy nl api to "nl compat"
The new netlink API is no longer "v2" but rather the standard API and
the legacy API is now "nl compat". We split them into separate
start/stop and put them in different files in order to further
distinguish them.

Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-09 13:20:47 -08:00
Ying Xue
bafa29e341 tipc: make tipc random value aware of net namespace
After namespace is supported, each namespace should own its private
random value. So the global variable representing the random value
must be moved to tipc_net structure.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
a62fbccecd tipc: make subscriber server support net namespace
TIPC establishes one subscriber server which allows users to subscribe
their interesting name service status. After tipc supports namespace,
one dedicated tipc stack instance is created for each namespace, and
each instance can be deemed as one independent TIPC node. As a result,
subscriber server must be built for each namespace.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
3474753954 tipc: make tipc node address support net namespace
If net namespace is supported in tipc, each namespace will be treated
as a separate tipc node. Therefore, every namespace must own its
private tipc node address. This means the "tipc_own_addr" global
variable of node address must be moved to tipc_net structure to
satisfy the requirement. It's turned out that users also can assign
node address for every namespace.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
4ac1c8d0ee tipc: name tipc name table support net namespace
TIPC name table is used to store the mapping relationship between
TIPC service name and socket port ID. When tipc supports namespace,
it allows users to publish service names only owned by a certain
namespace. Therefore, every namespace must have its private name
table to prevent service names published to one namespace from being
contaminated by other service names in another namespace. Therefore,
The name table global variable (ie, nametbl) and its lock must be
moved to tipc_net structure, and a parameter of namespace must be
added for necessary functions so that they can obtain name table
variable defined in tipc_net structure.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
e05b31f4bf tipc: make tipc socket support net namespace
Now tipc socket table is statically allocated as a global variable.
Through it, we can look up one socket instance with port ID, insert
a new socket instance to the table, and delete a socket from the
table. But when tipc supports net namespace, each namespace must own
its specific socket table. So the global variable of socket table
must be redefined in tipc_net structure. As a concequence, a new
socket table will be allocated when a new namespace is created, and
a socket table will be deallocated when namespace is destroyed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
f2f9800d49 tipc: make tipc node table aware of net namespace
Global variables associated with node table are below:
- node table list (node_htable)
- node hash table list (tipc_node_list)
- node table lock (node_list_lock)
- node number counter (tipc_num_nodes)
- node link number counter (tipc_num_links)

To make node table support namespace, above global variables must be
moved to tipc_net structure in order to keep secret for different
namespaces. As a consequence, these variables are allocated and
initialized when namespace is created, and deallocated when namespace
is destroyed. After the change, functions associated with these
variables have to utilize a namespace pointer to access them. So
adding namespace pointer as a parameter of these functions is the
major change made in the commit.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:32 -05:00
Ying Xue
c93d3baa24 tipc: involve namespace infrastructure
Involve namespace infrastructure, make the "tipc_net_id" global
variable aware of per namespace, and rename it to "net_id". In
order that the conversion can be successfully done, an instance
of networking namespace must be passed to relevant functions,
allowing them to access the "net_id" variable of per namespace.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:32 -05:00
Ying Xue
859fc7c0ce tipc: cleanup core.c and core.h files
Only the works of initializing and shutting down tipc module are done
in core.h and core.c files, so all stuffs which are not closely
associated with the two tasks should be moved to appropriate places.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:31 -05:00
Ying Xue
6b8326ed14 tipc: remove tipc_core_start/stop routines
Remove redundant wrapper functions like tipc_core_start() and
tipc_core_stop(), and directly move them to their callers, such
as tipc_init() and tipc_exit(), having us clearly know what are
really done in both initialization and deinitialzation functions.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:31 -05:00
Ying Xue
07f6c4bc04 tipc: convert tipc reference table to use generic rhashtable
As tipc reference table is statically allocated, its memory size
requested on stack initialization stage is quite big even if the
maximum port number is just restricted to 8191 currently, however,
the number already becomes insufficient in practice. But if the
maximum ports is allowed to its theory value - 2^32, its consumed
memory size will reach a ridiculously unacceptable value. Apart from
this, heavy tipc users spend a considerable amount of time in
tipc_sk_get() due to the read-lock on ref_table_lock.

If tipc reference table is converted with generic rhashtable, above
mentioned both disadvantages would be resolved respectively: making
use of the new resizable hash table can avoid locking on the lookup;
smaller memory size is required at initial stage, for example, 256
hash bucket slots are requested at the beginning phase instead of
allocating the entire 8191 slots in old mode. The hash table will
grow if entries exceeds 75% of table size up to a total table size
of 1M, and it will automatically shrink if usage falls below 30%,
but the minimum table size is allowed down to 256.

Also converts ref_table_lock to a separate mutex to protect hash table
mutations on write side. Lastly defers the release of the socket
reference using call_rcu() to allow using an RCU read-side protected
call to rhashtable_lookup().

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Erik Hugne <erik.hugne@ericsson.com>
Cc: Thomas Graf <tgraf@suug.ch>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-08 19:47:14 -08:00
Jon Paul Maloy
808d90f9c5 tipc: remove files ref.h and ref.c
The reference table is now 'socket aware' instead of being generic,
and has in reality become a socket internal table. In order to be
able to minimize the API exposed by the socket layer towards the rest
of the stack, we now move the reference table definitions and functions
into the file socket.c, and rename the functions accordingly.

There are no functional changes in this commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 11:18:35 -07:00
Jon Paul Maloy
2e84c60b77 tipc: remove include file port.h
We move the inline functions in the file port.h to socket.c, and modify
their names accordingly.

We move struct tipc_port and some macros to socket.h.

Finally, we remove the file port.h.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 11:18:35 -07:00
Jon Paul Maloy
6163a194e0 tipc: decrease connection flow control window
Memory overhead when allocating big buffers for data transfer may
be quite significant. E.g., truesize of a 64 KB buffer turns out
to be 132 KB, 2 x the requested size.

This invalidates the "worst case" calculation we have been
using to determine the default socket receive buffer limit,
which is based on the assumption that 1024x64KB = 67MB buffers
may be queued up on a socket.

Since TIPC connections cannot survive hitting the buffer limit,
we have to compensate for this overhead.

We do that in this commit by dividing the fix connection flow
control window from 1024 (2*512) messages to 512 (2*256). Since
older version nodes send out acks at 512 message intervals,
compatibility with such nodes is guaranteed, although performance
may be non-optimal in such cases.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14 15:19:47 -04:00
Ying Xue
52ff872055 tipc: purge signal handler infrastructure
In the previous commits of this series, we removed all asynchronous
actions which were based on the tasklet handler - "tipc_k_signal()".

So the moment has now come when we can completely remove the tasklet
handler infrastructure. That is done with this commit.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-05 17:26:45 -04:00
Ying Xue
5902385a24 tipc: obsolete the remote management feature
Due to the lacking of any credential, it's allowed to accept commands
requested from remote nodes to query the local node status, which is
prone to involve potential security risks. Instead, if we login to
a remote node with ssh command, this approach is not only more safe
than the remote management feature, but also it can give us more
permissions like changing the remote node configuration. So it's
reasonable for us to obsolete the remote management feature now.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-27 13:08:36 -04:00
David S. Miller
67ddc87f16 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/wireless/ath/ath9k/recv.c
	drivers/net/wireless/mwifiex/pcie.c
	net/ipv6/sit.c

The SIT driver conflict consists of a bug fix being done by hand
in 'net' (missing u64_stats_init()) whilst in 'net-next' a helper
was created (netdev_alloc_pcpu_stats()) which takes care of this.

The two wireless conflicts were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-05 20:32:02 -05:00
Ying Xue
970122fdf4 tipc: make bearer set up in module insertion stage
Accidentally a side effect is involved by commit 6e967adf7(tipc:
relocate common functions from media to bearer). Now tipc stack
handler of receiving packets from netdevices as well as netdevice
notification handler are registered when bearer is enabled rather
than tipc module initialization stage, but the two handlers are
both unregistered in tipc module exit phase. If tipc module is
inserted and then immediately removed, the following warning
message will appear:

"dev_remove_pack: ffffffffa0380940 not found"

This is because in module insertion stage tipc stack packet handler
is not registered at all, but in module exit phase dev_remove_pack()
needs to remove it. Of course, dev_remove_pack() cannot find tipc
protocol handler from the kernel protocol handler list so that the
warning message is printed out.

But if registering the two handlers is adjusted from enabling bearer
phase into inserting module stage, the warning message will be
eliminated. Due to this change, tipc_core_start_net() and
tipc_core_stop_net() can be deleted as well.

Reported-by: Wang Weidong <wangweidong1@huawei.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-22 00:00:15 -05:00
Ying Xue
9fe7ed4749 tipc: remove all enabled flags from all tipc components
When tipc module is inserted, many tipc components are initialized
one by one. During the initialization period, if one of them is
failed, tipc_core_stop() will be called to stop all components
whatever corresponding components are created or not. To avoid to
release uncreated ones, relevant components have to add necessary
enabled flags indicating whether they are created or not.

But in the initialization stage, if one component is unsuccessfully
created, we will just destroy successfully created components before
the failed component instead of all components. All enabled flags
defined in components, in turn, become redundant. Additionally it's
also unnecessary to identify whether table.types is NULL in
tipc_nametbl_stop() because name stable has been definitely created
successfully when tipc_nametbl_stop() is called.

Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-22 00:00:15 -05:00
Ying Xue
c61dd61dec tipc: remove 'links' list from tipc_bearer struct
In our ongoing effort to simplify the TIPC locking structure,
we see a need to remove the linked list for tipc_links
in the bearer. This can be explained as follows.

Currently, we have three different ways to access a link,
via three different lists/tables:

1: Via a node hash table:
   Used by the time-critical outgoing/incoming data paths.
   (e.g. link_send_sections_fast() and tipc_recv_msg() ):

grab net_lock(read)
   find node from node hash table
   grab node_lock
       select link
       grab bearer_lock
          send_msg()
       release bearer_lock
   release node lock
release net_lock

2: Via a global linked list for nodes:
   Used by configuration commands (link_cmd_set_value())

grab net_lock(read)
   find node and link from global node list (using link name)
   grab node_lock
       update link
   release node lock
release net_lock

(Same locking order as above. No problem.)

3: Via the bearer's linked link list:
   Used by notifications from interface (e.g. tipc_disable_bearer() )

grab net_lock(write)
   grab bearer_lock
      get link ptr from bearer's link list
      get node from link
      grab node_lock
         delete link
      release node lock
   release bearer_lock
release net_lock

(Different order from above, but works because we grab the
outer net_lock in write mode first, excluding all other access.)

The first major goal in our simplification effort is to get rid
of the "big" net_lock, replacing it with rcu-locks when accessing
the node list and node hash array. This will come in a later patch
series.

But to get there we first need to rewrite access methods ##2 and 3,
since removal of net_lock would introduce three major problems:

a) In access method #2, we access the link before taking the
   protecting node_lock. This will not work once net_lock is gone,
   so we will have to change the access order. We will deal with
   this in a later commit in this series, "tipc: add node lock
   protection to link found by link_find_link()".

b) When the outer protection from net_lock is gone, taking
   bearer_lock and node_lock in opposite order of method 1) and 2)
   will become an obvious deadlock hazard. This is fixed in the
   commit ("tipc: remove bearer_lock from tipc_bearer struct")
   later in this series.

c) Similar to what is described in problem a), access method #3
   starts with using a link pointer that is unprotected by node_lock,
   in order to via that pointer find the correct node struct and
   lock it. Before we remove net_lock, this access order must be
   altered. This is what we do with this commit.

We can avoid introducing problem problem c) by even here using the
global node list to find the node, before accessing its links. When
we loop though the node list we use the own bearer identity as search
criteria, thus easily finding the links that are associated to the
resetting/disabling bearer. It should be noted that although this
method is somewhat slower than the current list traversal, it is in
no way time critical. This is only about resetting or deleting links,
something that must be considered relatively infrequent events.

As a bonus, we can get rid of the mutual pointers between links and
bearers. After this commit, pointer dependency go in one direction
only: from the link to the bearer.

This commit pre-empts introduction of problem c) as described above.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13 17:57:05 -05:00
David S. Miller
143c905494 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/i40e/i40e_main.c
	drivers/net/macvtap.c

Both minor merge hassles, simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 16:42:06 -05:00
Ying Xue
6e967adf79 tipc: relocate common functions from media to bearer
Currently, registering a TIPC stack handler in the network device layer
is done twice, once for Ethernet (eth_media) and Infiniband (ib_media)
repectively. But, as this registration is not media specific, we can
avoid some code duplication by moving the registering function to
the generic bearer layer, to the file bearer.c, and call it only once.
The same is true for the network device event notifier.

As a side effect, the two workqueues we are using for for setting up/
cleaning up media can now be eliminated. Furthermore, the array for
storing the specific media type structs, media_array[], can be entirely
deleted.

Note that the eth_started and ib_started flags were removed during the
code relocation.  There is now only one call to bearer_setup and
bearer_cleanup, and these can logically not race against each other.

Despite its size, this cleanup work incurs no functional changes in TIPC.
In particular, it should be noted that the sequence ordering of received
packets is unaffected by this change, since packet reception never was
subject to any work queue handling in the first place.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11 00:17:43 -05:00
Jon Paul Maloy
993b858e37 tipc: correct the order of stopping services at rmmod
The 'signal handler' service in TIPC is a mechanism that makes it
possible to postpone execution of functions, by launcing them into
a job queue for execution in a separate tasklet, independent of
the launching execution thread.

When we do rmmod on the tipc module, this service is stopped after
the network service. At the same time, the stopping of the network
service may itself launch jobs for execution, with the risk that these
functions may be scheduled for execution after the data structures
meant to be accessed by the job have already been deleted. We have
seen this happen, most often resulting in an oops.

This commit ensures that the signal handler is the very first to be
stopped when TIPC is shut down, so there are no surprises during
the cleanup of the other services.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:35:49 -05:00
Ying Xue
7d0ab17b74 tipc: convert configuration server to use new server facility
As the new socket-based TIPC server infrastructure has been
introduced, we can now convert the configuration server to use
it.  Then we can take future steps to simplify the configuration
server locking policy.

Some minor reordering of initialization is done, due to the
dependency on having tipc_socket_init completed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue
13a2e89873 tipc: convert topology server to use new server facility
As the new TIPC server infrastructure has been introduced, we can
now convert the TIPC topology server to it.  We get two benefits
from doing this:

1) It simplifies the topology server locking policy.  In the
original locking policy, we placed one spin lock pointer in the
tipc_subscriber structure to reuse the lock of the subscriber's
server port, controlling access to members of tipc_subscriber
instance.  That is, we only used one lock to ensure both
tipc_port and tipc_subscriber members were safely accessed.

Now we introduce another spin lock for tipc_subscriber structure
only protecting themselves, to get a finer granularity locking
policy.  Moreover, the change will allow us to make the topology
server code more readable and maintainable.

2) It fixes a bug where sent subscription events may be lost when
the topology port is congested.  Using the new service, the
topology server now queues sent events into an outgoing buffer,
and then wakes up a sender process which has been blocked in
workqueue context.  The process will keep picking events from the
buffer and send them to their respective subscribers, using the
kernel socket interface, until the buffer is empty. Even if the
socket is congested during transmission there is no risk that
events may be dropped, since the sender process may block when
needed.

Some minor reordering of initialization is done, since we now
have a scenario where the topology server must be started after
socket initialization has taken place, as the former depends
on the latter.  And overall, we see a simplification of the
TIPC subscriber code in making this changeover.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
Ying Xue
cc79dd1ba9 tipc: change socket buffer overflow control to respect sk_rcvbuf
As per feedback from the netdev community, we change the buffer
overflow protection algorithm in receiving sockets so that it
always respects the nominal upper limit set in sk_rcvbuf.

Instead of scaling up from a small sk_rcvbuf value, which leads to
violation of the configured sk_rcvbuf limit, we now calculate the
weighted per-message limit by scaling down from a much bigger value,
still in the same field, according to the importance priority of the
received message.

To allow for administrative tunability of the socket receive buffer
size, we create a tipc_rmem sysctl variable to allow the user to
configure an even bigger value via sysctl command.  It is a size of
three (min/default/max) to be consistent with things like tcp_rmem.

By default, the value initialized in tipc_rmem[1] is equal to the
receive socket size needed by a TIPC_CRITICAL_IMPORTANCE message.
This value is also set as the default value of sk_rcvbuf.

Originally-by: Jon Maloy <jon.maloy@ericsson.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
[Ying: added sysctl variation to Jon's original patch]
Signed-off-by: Ying Xue <ying.xue@windriver.com>
[PG: don't compile sysctl.c if not config'd; add Documentation]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00