Commit Graph

78 Commits

Author SHA1 Message Date
Jon Paul Maloy
1a90632da8 tipc: eliminate remnants of hungarian notation
The number of variables with Hungarian notation (l_ptr, n_ptr etc.)
has been significantly reduced over the last couple of years.

We now root out the last traces of this practice.
There are no functional changes in this commit.

Reviewed-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>
2015-11-20 14:06:10 -05:00
Jon Paul Maloy
60852d6795 tipc: let neighbor discoverer tranmsit consumable buffers
The neighbor discovery function currently uses the function
tipc_bearer_send() for transmitting packets, assuming that the
sent buffers are not consumed by the called function.

We want to change this, in order to avoid unnecessary buffer cloning
elswhere in the code.

This commit introduces a new function tipc_bearer_skb() which consumes
the sent buffers, and let the discoverer functions use this new call
instead. The discoverer does now itself perform the cloning when
that is necessary.

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 06:56:44 -07:00
Jon Paul Maloy
fd556f209a tipc: introduce capability bit for broadcast synchronization
Until now, we have tried to support both the newer, dedicated broadcast
synchronization mechanism along with the older, less safe, RESET_MSG/
ACTIVATE_MSG based one. The latter method has turned out to be a hazard
in a highly dynamic cluster, so we find it safer to disable it completely
when we find that the former mechanism is supported by the peer node.

For this purpose, we now introduce a new capabability bit,
TIPC_BCAST_SYNCH, to inform any peer nodes that dedicated broadcast
syncronization is supported by the present node. The new bit is conveyed
between peers in the 'capabilities' field of neighbor discovery messages.

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 06:56:35 -07:00
Jon Paul Maloy
cf148816ac tipc: move received discovery data evaluation inside node.c
The node lock is currently grabbed and and released in the function
tipc_disc_rcv() in the file discover.c. As a preparation for the next
commits, we need to move this node lock handling, along with the code
area it is covering, to node.c.

This commit introduces this change.

Tested-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>
2015-07-30 17:25:14 -07:00
Jon Paul Maloy
d3a43b907a tipc: move link creation from neighbor discoverer to node
As a step towards turning links into node internal entities, we move the
creation of links from the neighbor discovery logics to the node's link
control logics.

We also create an additional entry for the link's media address in the
newly introduced struct tipc_link_entry, since this is where it is
needed in the upcoming commits. The current copy in struct tipc_link
is kept for now, but will be removed later.

Reviewed-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>
2015-07-20 20:41:14 -07:00
Jon Paul Maloy
9d13ec65ed tipc: introduce link entry structure to struct tipc_node
struct 'tipc_node' currently contains two arrays for link attributes,
one for the link pointers, and one for the usable link MTUs.

We now group those into a new struct 'tipc_link_entry', and intoduce
one single array consisting of such enties. Apart from being a cosmetic
improvement, this is a starting point for the strict master-slave
relation between node and link that we will introduce in the following
commits.

Reviewed-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>
2015-07-20 20:41:14 -07:00
Ying Xue
8a0f6ebe84 tipc: involve reference counter for node structure
TIPC node hash node table is protected with rcu lock on read side.
tipc_node_find() is used to look for a node object with node address
through iterating the hash node table. As the entire process of what
tipc_node_find() traverses the table is guarded with rcu read lock,
it's safe for us. However, when callers use the node object returned
by tipc_node_find(), there is no rcu read lock applied. Therefore,
this is absolutely unsafe for callers of tipc_node_find().

Now we introduce a reference counter for node structure. Before
tipc_node_find() returns node object to its caller, it first increases
the reference counter. Accordingly, after its caller used it up,
it decreases the counter again. This can prevent a node being used by
one thread from being freed by another thread.

Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-29 12:40:28 -07:00
Jon Paul Maloy
7764d6e83d tipc: add framework for node capabilities exchange
The TIPC protocol spec has defined a 13 bit capability bitmap in
the neighbor discovery header, as a means to maintain compatibility
between different code and protocol generations. Until now this field
has been unused.

We now introduce the basic framework for exchanging capabilities
between nodes at first contact. After exchange, a peer node's
capabilities are stored as a 16 bit bitmap in struct tipc_node.

Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>
2015-03-14 14:38:32 -04:00
Erik Hugne
948fa2d115 tipc: increase size of tipc discovery messages
The payload area following the TIPC discovery message header is an
opaque area defined by the media. INT_H_SIZE was enough for
Ethernet/IB/IPv4 but needs to be expanded to carry IPv6 addressing
information.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-05 22:08:42 -05:00
Jon Paul Maloy
c5898636c4 tipc: reduce usage of context info in socket and link
The most common usage of namespace information is when we fetch the
own node addess from the net structure. This leads to a lot of
passing around of a parameter of type 'struct net *' between
functions just to make them able to obtain this address.

However, in many cases this is unnecessary. The own node address
is readily available as a member of both struct tipc_sock and
tipc_link, and can be fetched from there instead.
The fact that the vast majority of functions in socket.c and link.c
anyway are maintaining a pointer to their respective base structures
makes this option even more compelling.

In this commit, we introduce the inline functions tsk_own_node()
and link_own_node() to make it easy for functions to fetch the node
address from those structs instead of having to pass along and
dereference the namespace struct.

In particular, we make calls to the msg_xx() functions in msg.{h,c}
context independent by directly passing them the own node address
as parameter when needed. Those functions should be regarded as
leaves in the code dependency tree, and it is hence desirable to
keep them namspace unaware.

Apart from a potential positive effect on cache behavior, these
changes make it easier to introduce the changes that will follow
later in this series.

Reviewed-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>
2015-02-05 16:00:01 -08:00
Jon Paul Maloy
b45db71b52 tipc: eliminate race during node creation
Instances of struct node are created in the function tipc_disc_rcv()
under the assumption that there is no race between received discovery
messages arriving from the same node. This assumption is wrong.
When we use more than one bearer, it is possible that discovery
messages from the same node arrive at the same moment, resulting in
creation of two instances of struct tipc_node. This may later cause
confusion during link establishment, and may result in one of the links
never becoming activated.

We fix this by making lookup and potential creation of nodes atomic.
Instead of first looking up the node, and in case of failure, create it,
we now start with looking up the node inside node_link_create(), and
return a reference to that one if found. Otherwise, we go ahead and
create the node as we did before.

Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>
2015-02-04 16:09:31 -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
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
7f9f95d9d9 tipc: make bearer list support net namespace
Bearer list defined as a global variable is used to store bearer
instances. When tipc supports net namespace, bearers created in
one namespace must be isolated with others allocated in other
namespaces, which requires us that the bearer list(bearer_list)
must be moved to tipc_net structure. As a result, a net namespace
pointer has to be passed to functions which access the bearer list.

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
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
2f55c43788 tipc: remove unnecessary wrapper functions of kernel timer APIs
Not only some wrapper function like k_term_timer() is empty, but also
some others including k_start_timer() and k_cancel_timer() don't return
back any value to its caller, what's more, there is no any component
in the kernel world to do such thing. Therefore, these timer interfaces
defined in tipc module should be purged.

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
Jon Paul Maloy
c82910e2a8 tipc: clean up neigbor discovery message reception
The function tipc_disc_rcv(), which is handling received neighbor
discovery messages, is perceived as messy, and it is hard to verify
its correctness by code inspection. The fact that the task it is set
to resolve is fairly complex does not make the situation better.

In this commit we try to take a more systematic approach to the
problem. We define a decision machine which takes three state flags
 as input, and produces three action flags as output. We then walk
through all permutations of the state flags, and for each of them we
describe verbally what is going on, plus that we set zero or more of
the action flags. The action flags indicate what should be done once
the decision machine has finished its job, while the last part of the
function deals with performing those actions.

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 15:19:48 -04:00
Jon Paul Maloy
38504c28a2 tipc: improve and extend media address conversion functions
TIPC currently handles two media specific addresses: Ethernet MAC
addresses and InfiniBand addresses. Those are kept in three different
formats:

1) A "raw" format as obtained from the device. This format is known
   only by the media specific adapter code in eth_media.c and
   ib_media.c.
2) A "generic" internal format, in the form of struct tipc_media_addr,
   which can be referenced and passed around by the generic media-
   unaware code.
3) A serialized version of the latter, to be conveyed in neighbor
   discovery messages.

Conversion between the three formats can only be done by the media
specific code, so we have function pointers for this purpose in
struct tipc_media. Here, the media adapters can install their own
conversion functions at startup.

We now introduce a new such function, 'raw2addr()', whose purpose
is to convert from format 1 to format 2 above. We also try to as far
as possible uniform commenting, variable names and usage of these
functions, with the purpose of making them more comprehensible.

We can now also remove the function tipc_l2_media_addr_set(), whose
job is done better by the new function.

Finally, we expand the field for serialized addresses (format 3)
in discovery messages from 20 to 32 bytes. This is permitted
according to the spec, and reduces the risk of problems when we
add new media in the future.

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 15:19:48 -04:00
Ying Xue
22e7987ae7 tipc: fix a possible memory leak
The commit a8b9b96e95 ("tipc: fix race
in disc create/delete") leads to the following static checker warning:

	net/tipc/discover.c:352 tipc_disc_create()
		warn: possible memory leak of 'req'

The risk of memory leak really exists in practice. Especially when
it's failed to allocate memory for "req->buf", tipc_disc_create()
doesn't free its allocated memory, instead just directly returns
with ENOMEM error code. In this situation, memory leak, of course,
happens.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-27 19:08:06 -04:00
Ying Xue
a8b9b96e95 tipc: fix race in disc create/delete
Commit a21a584d67 (tipc: fix neighbor
detection problem after hw address change) introduces a race condition
involving tipc_disc_delete() and tipc_disc_add/remove_dest that can
cause TIPC to dereference the pointer to the bearer discovery request
structure after it has been freed since a stray pointer is left in the
bearer structure.

In order to fix the issue, the process of resetting the discovery
request handler is optimized: the discovery request handler and request
buffer are just reset instead of being freed, allocated and initialized.
As the request point is always valid and the request's lock is taken
while the request handler is reset, the race doesn't happen any more.

Reported-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Tested-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 21:17:53 -04:00
Ying Xue
7a2f7d18e7 tipc: decouple the relationship between bearer and link
Currently on both paths of message transmission and reception, the
read lock of tipc_net_lock must be held before bearer is accessed,
while the write lock of tipc_net_lock has to be taken before bearer
is configured. Although it can ensure that bearer is always valid on
the two data paths, link and bearer is closely bound together.

So as the part of effort of removing tipc_net_lock, the locking
policy of bearer protection will be adjusted as below: on the two
data paths, RCU is used, and on the configuration path of bearer,
RTNL lock is applied.

Now RCU just covers the path of message reception. To make it possible
to protect the path of message transmission with RCU, link should not
use its stored bearer pointer to access bearer, but it should use the
bearer identity of its attached bearer as index to get bearer instance
from bearer_list array, which can help us decouple the relationship
between bearer and link. As a result, bearer on the path of message
transmission can be safely protected by RCU when we access bearer_list
array within RCU lock protection.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Tested-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-22 21:17:53 -04:00
Erik Hugne
16470111ed tipc: make discovery domain a bearer attribute
The node discovery domain is assigned when a bearer is enabled.
In the previous commit we reflect this attribute directly in the
bearer structure since it's needed to reinitialize the node
discovery mechanism after a hardware address change.

There's no need to replicate this attribute anywhere else, so we
remove it from the tipc_link_req structure.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-28 14:46:29 -04:00
Ying Xue
247f0f3c31 tipc: align tipc function names with common naming practice in the network
Rename the following functions, which are shorter and more in line
with common naming practice in the network subsystem.

tipc_bclink_send_msg->tipc_bclink_xmit
tipc_bclink_recv_pkt->tipc_bclink_rcv
tipc_disc_recv_msg->tipc_disc_rcv
tipc_link_send_proto_msg->tipc_link_proto_xmit
link_recv_proto_msg->tipc_link_proto_rcv
link_send_sections_long->tipc_link_iovec_long_xmit
tipc_link_send_sections_fast->tipc_link_iovec_xmit_fast
tipc_link_send_sync->tipc_link_sync_xmit
tipc_link_recv_sync->tipc_link_sync_rcv
tipc_link_send_buf->__tipc_link_xmit
tipc_link_send->tipc_link_xmit
tipc_link_send_names->tipc_link_names_xmit
tipc_named_recv->tipc_named_rcv
tipc_link_recv_bundle->tipc_link_bundle_rcv
tipc_link_dup_send_queue->tipc_link_dup_queue_xmit
link_send_long_buf->tipc_link_frag_xmit

tipc_multicast->tipc_port_mcast_xmit
tipc_port_recv_mcast->tipc_port_mcast_rcv
tipc_port_reject_sections->tipc_port_iovec_reject
tipc_port_recv_proto_msg->tipc_port_proto_rcv
tipc_connect->tipc_port_connect
__tipc_connect->__tipc_port_connect
__tipc_disconnect->__tipc_port_disconnect
tipc_disconnect->tipc_port_disconnect
tipc_shutdown->tipc_port_shutdown
tipc_port_recv_msg->tipc_port_rcv
tipc_port_recv_sections->tipc_port_iovec_rcv

release->tipc_release
accept->tipc_accept
bind->tipc_bind
get_name->tipc_getname
poll->tipc_poll
send_msg->tipc_sendmsg
send_packet->tipc_send_packet
send_stream->tipc_send_stream
recv_msg->tipc_recvmsg
recv_stream->tipc_recv_stream
connect->tipc_connect
listen->tipc_listen
shutdown->tipc_shutdown
setsockopt->tipc_setsockopt
getsockopt->tipc_getsockopt

Above changes have no impact on current users of the functions.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-18 17:31:59 -05:00
Ying Xue
f9a2c80b8b tipc: introduce new spinlock to protect struct link_req
Currently, only 'bearer_lock' is used to protect struct link_req in
the function disc_timeout(). This is unsafe, since the member fields
'num_nodes' and 'timer_intv' might be accessed by below three different
threads simultaneously, none of them grabbing bearer_lock in the
critical region:

link_activate()
  tipc_bearer_add_dest()
    tipc_disc_add_dest()
      req->num_nodes++;

tipc_link_reset()
  tipc_bearer_remove_dest()
    tipc_disc_remove_dest()
      req->num_nodes--
      disc_update()
        read req->num_nodes
	write req->timer_intv

disc_timeout()
  read req->num_nodes
  read/write req->timer_intv

Without lock protection, the only symptom of a race is that discovery
messages occasionally may not be sent out. This is not fatal, since such
messages are best-effort anyway. On the other hand, since discovery
messages are not time critical, adding a protecting lock brings no
serious overhead either. So we add a new, dedicated spinlock in
order to guarantee absolute data consistency in link_req objects.
This also helps reduce the overall role of the bearer_lock, which
we want to remove completely in a later commit series.

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>
2014-01-07 18:44:25 -05:00
Erik Hugne
512137eeff tipc: remove interface state mirroring in bearer
struct 'tipc_bearer' is a generic representation of the underlying
media type, and exists in a one-to-one relationship to each interface
TIPC is using. The struct contains a 'blocked' flag that mirrors the
operational and execution state of the represented interface, and is
updated through notification calls from the latter. The users of
tipc_bearer are checking this flag before each attempt to send a
packet via the interface.

This state mirroring serves no purpose in the current code base. TIPC
links will not discover a media failure any faster through this
mechanism, and in reality the flag only adds overhead at packet
sending and reception.

Furthermore, the fact that the flag needs to be protected by a spinlock
aggregated into tipc_bearer has turned out to cause a serious and
completely unnecessary deadlock problem.

CPU0                                    CPU1
----                                    ----
Time 0: bearer_disable()                link_timeout()
Time 1:   spin_lock_bh(&b_ptr->lock)      tipc_link_push_queue()
Time 2:   tipc_link_delete()                tipc_bearer_blocked(b_ptr)
Time 3:     k_cancel_timer(&req->timer)       spin_lock_bh(&b_ptr->lock)
Time 4:       del_timer_sync(&req->timer)

I.e., del_timer_sync() on CPU0 never returns, because the timer handler
on CPU1 is waiting for the bearer lock.

We eliminate the 'blocked' flag from struct tipc_bearer, along with all
tests on this flag. This not only resolves the deadlock, but also
simplifies and speeds up the data path execution of TIPC. It also fits
well into our ongoing effort to make the locking policy simpler and
more manageable.

An effect of this change is that we can get rid of functions such as
tipc_bearer_blocked(), tipc_continue() and tipc_block_bearer().
We replace the latter with a new function, tipc_reset_bearer(), which
resets all links associated to the bearer immediately after an
interface goes down.

A user might notice one slight change in link behaviour after this
change. When an interface goes down, (e.g. through a NETDEV_DOWN
event) all attached links will be reset immediately, instead of
leaving it to each link to detect the failure through a timer-driven
mechanism. We consider this an improvement, and see no obvious risks
with the new behavior.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-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>
2013-12-09 20:30:29 -05:00
Paul Gortmaker
ae8509c420 tipc: cosmetic realignment of function arguments
No runtime code changes here.  Just a realign of the function
arguments to start where the 1st one was, and fit as many args
as can be put in an 80 char line.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:01 -07:00
Patrick McHardy
8aeb89f214 tipc: move bcast_addr from struct tipc_media to struct tipc_bearer
Some network protocols, like InfiniBand, don't have a fixed broadcast
address but one that depends on the configuration. Move the bcast_addr
to struct tipc_bearer and initialize it with the broadcast address of
the network device when the bearer is enabled.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-17 14:18:33 -04:00
Ying Xue
3c294cb374 tipc: remove the bearer congestion mechanism
Currently at the TIPC bearer layer there is the following congestion
mechanism:

Once sending packets has failed via that bearer, the bearer will be
flagged as being in congested state at once. During bearer congestion,
all packets arriving at link will be queued on the link's outgoing
buffer.  When we detect that the state of bearer congestion has
relaxed (e.g. some packets are received from the bearer) we will try
our best to push all packets in the link's outgoing buffer until the
buffer is empty, or until the bearer is congested again.

However, in fact the TIPC bearer never receives any feedback from the
device layer whether a send was successful or not, so it must always
assume it was successful. Therefore, the bearer congestion mechanism
as it exists currently is of no value.

But the bearer blocking state is still useful for us. For example,
when the physical media goes down/up, we need to change the state of
the links bound to the bearer.  So the code maintaing the state
information is not removed.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-11-21 20:07:25 -05:00
Erik Hugne
dc1aed37d1 tipc: phase out most of the struct print_buf usage
The tipc_printf is renamed to tipc_snprintf, as the new name
describes more what the function actually does.  It is also
changed to take a buffer and length parameter and return
number of characters written to the buffer.  All callers of
this function that used to pass a print_buf are updated.

Final removal of the struct print_buf itself will be done
synchronously with the pending removal of the deprecated
logging code that also was using it.

Functions that build up a response message with a list of
ports, nametable contents etc. are changed to return the number
of characters written to the output buffer. This information
was previously hidden in a field of the print_buf struct, and
the number of chars written was fetched with a call to
tipc_printbuf_validate.  This function is removed since it
is no longer referenced nor needed.

A generic max size ULTRA_STRING_MAX_LEN is defined, named
in keeping with the existing TIPC_TLV_ULTRA_STRING, and the
various definitions in port, link and nametable code that
largely duplicated this information are removed.  This means
that amount of link statistics that can be returned is now
increased from 2k to 32k.

The buffer overflow check is now done just before the reply
message is passed over netlink or TIPC to a remote node and
the message indicating a truncated buffer is changed to a less
dramatic one (less CAPS), placed at the end of the message.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-07-13 19:33:28 -04:00
Erik Hugne
2cf8aa19fe tipc: use standard printk shortcut macros (pr_err etc.)
All messages should go directly to the kernel log.  The TIPC
specific error, warning, info and debug trace macro's are
removed and all references replaced with pr_err, pr_warn,
pr_info and pr_debug.

Commonly used sub-strings are explicitly declared as a const
char to reduce .text size.

Note that this means the debug messages (changed to pr_debug),
are now enabled through dynamic debugging, instead of a TIPC
specific Kconfig option (TIPC_DEBUG).  The latter will be
phased out completely

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
[PG: use pr_fmt as suggested by Joe Perches <joe@perches.com>]
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-07-13 19:24:44 -04:00
Paul Gortmaker
617d3c7a50 tipc: compress out gratuitous extra carriage returns
Some of the comment blocks are floating in limbo between two
functions, or between blocks of code.  Delete the extra line
feeds between any comment and its associated following block
of code, to be consistent with the majority of the rest of
the kernel.  Also delete trailing newlines at EOF and fix
a couple trivial typos in existing comments.

This is a 100% cosmetic change with no runtime impact.  We get
rid of over 500 lines of non-code, and being blank line deletes,
they won't even show up as noise in git blame.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-30 15:53:56 -04:00
Allan Stephens
5f6d9123f1 tipc: Eliminate trivial buffer manipulation helper routines
Gets rid of two inlined routines that simply call existing sk_buff
manipulation routines, since there is no longer any extra processing
done by the helper routines.

Note that these changes are essentially cosmetic in nature, and have
no impact on the actual operation of TIPC.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:16 -05:00
Allan Stephens
97878a405c tipc: Detect duplicate nodes using different network interfaces
Utilizes the new "node signature" field in neighbor discovery messages
to ensure that all links TIPC associates with a given <Z.C.N> network
address belong to the same neighboring node. (Previously, TIPC could not
tell if link setup requests arriving on different interfaces were from
the same node or from two different nodes that has mistakenly been assigned
the same network address.)

The revised algorithm for detecting a duplicate node considers both the
node signature and the network interface adddress specified in a request
message when deciding how to respond to a link setup request. This prevents
false alarms that might otherwise arise during normal network operation
under the following scenarios:

a) A neighboring node reboots. (The node's signature changes, but the
network interface address remains unchanged.)

b) A neighboring node's network interface is replaced. (The node's signature
remains unchanged, but the network interface address changes.)

c) A neighboring node is completely replaced. (The node's signature and
network interface address both change.)

The algorithm also handles cases in which a node reboots and re-establishes
its links to TIPC (or begins re-establishing those links) before TIPC
detects that it is using a new node signature. In such cases of "delayed
rediscovery" TIPC simply accepts the new signature without disrupting
communication that is already underway over the links.

Thanks to Laser [gotolaser@gmail.com] for his contributions to the
development of this enhancement.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:13 -05:00
Allan Stephens
fc0eea691a tipc: Introduce node signature field in neighbor discovery message
Adds support for the new "node signature" in neighbor discovery messages,
which is a 16 bit identifier chosen randomly when TIPC is initialized.
This field makes it possible for nodes receiving a neighbor discovery
message to detect if multiple neighboring nodes are using the same network
address (i.e. <Z.C.N>), even when the messages are arriving on different
interfaces.

This first phase of node signature support creates the signature,
incorporates it into outgoing neighbor discovery messages, and tracks
the signature used by valid neighbors. An upcoming patch builds on this
foundation to implement the improved duplicate neighbor detection checking.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:13 -05:00
Paul Gortmaker
a18c4bc3ea tipc: rename struct link* to struct tipc_link*
This converts the following:

	struct link		->	struct tipc_link
	struct link_req		->	struct tipc_link_req
	struct link_name	->	struct tipc_link_name

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-29 21:53:30 -05:00
Allan Stephens
d6d4577ae4 tipc: Ignore neighbor discovery messages containing invalid address
Adds a check to ensure that TIPC ignores an incoming neighbor discovery
message that specifies an invalid media address as its source. The check
ensures that the source address is a valid, non-broadcast address that
could legally be used by a neighboring link endpoint.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-27 11:33:38 -05:00
Allan Stephens
3d749a6a26 tipc: Hide media-specific addressing details from generic bearer code
Reworks TIPC's media address data structure and associated processing
routines to transfer all media-specific details of address conversion
to the associated TIPC media adaptation code. TIPC's generic bearer code
now only needs to know which media type an address is associated with
and whether or not it is a broadcast address, and totally ignores the
"value" field that contains the actual media-specific addressing info.

These changes eliminate the need for a number of endianness conversion
operations and will make it easier for TIPC to support new media types
in the future.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-27 11:33:36 -05:00
Allan Stephens
b4b5610223 tipc: Ensure both nodes recognize loss of contact between them
Enhances TIPC to ensure that a node that loses contact with a
neighboring node does not allow contact to be re-established until
it sees that its peer has also recognized the loss of contact.

Previously, nodes that were connected by two or more links could
encounter a situation in which node A would lose contact with node B
on all of its links, purge its name table of names published by B,
and then fail to repopulate those names once contact with B was restored.
This would happen because B was able to re-establish one or more links
so quickly that it never reached a point where it had no links to A --
meaning that B never saw a loss of contact with A, and consequently
didn't re-publish its names to A.

This problem is now prevented by enhancing the cleanup done by TIPC
following a loss of contact with a neighboring node to ensure that
node A ignores all messages sent by B until it receives a LINK_PROTOCOL
message that indicates B has lost contact with A, thereby preventing
the (re)establishment of links between the nodes. The loss of contact
is recognized when a RESET or ACTIVATE message is received that has
a "redundant link exists" field of 0, indicating that B's sending link
endpoint is in a reset state and that B has no other working links.

Additionally, TIPC now suppresses the sending of (most) link protocol
messages to a neighboring node while it is cleaning up after an earlier
loss of contact with that node. This stops the peer node from prematurely
activating its link endpoint, which would prevent TIPC from later
activating its own end. TIPC still allows outgoing RESET messages to
occur during cleanup, to avoid problems if its own node recognizes
the loss of contact first and tries to notify the peer of the situation.

Finally, TIPC now recognizes an impending loss of contact with a peer node
as soon as it receives a RESET message on a working link that is the
peer's only link to the node, and ensures that the link protocol
suppression mentioned above goes into effect right away -- that is,
even before its own link endpoints have failed. This is necessary to
ensure correct operation when there are redundant links between the nodes,
since otherwise TIPC would send an ACTIVATE message upon receiving a RESET
on its first link and only begin suppressing when a RESET on its second
link was received, instead of initiating suppression with the first RESET
message as it needs to.

Note: The reworked cleanup code also eliminates a check that prevented
a link endpoint's discovery object from responding to incoming messages
while stale name table entries are being purged. This check is now
unnecessary and would have slowed down re-establishment of communication
between the nodes in some situations.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-09-17 22:55:03 -04:00
Allan Stephens
972a77fbf1 tipc: Revise timings used when sending link request messages
Revises the algorithm governing the sending of link request messages
to take into account the number of nodes each bearer is currently in
contact with, and to ensure more rapid rediscovery of neighboring nodes
if a bearer fails and then recovers.

The discovery object now sends requests at least once a second if it
is not in contact with any other nodes, and at least once a minute if
it has at least one neighbor; if contact with the only neighbor is
lost, the object immediately reverts to its initial rapid-fire search
timing to accelerate the rediscovery process.

In addition, the discovery object now stops issuing link request
messages if it is in contact with the only neighboring node it is
configured to communicate with, since further searching is unnecessary.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:04:02 -04:00
Allan Stephens
1209966cd5 tipc: Add monitoring of number of nodes discovered by bearer
Augments TIPC's discovery object to track the number of neighboring nodes
having an active link to the associated bearer.

This means tipc_disc_update_link_req() becomes either one of:

       tipc_disc_add_dest()
or:
       tipc_disc_remove_dest()

depending on the code flow direction of things.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:04:01 -04:00
Allan Stephens
691a620759 tipc: Enhance sending of discovery object link request messages
Augments TIPC's discovery object to send its initial neighbor discovery
request message as soon as the associated bearer is created, rather than
waiting for its first periodic timeout to occur, thereby speeding up the
discovery process. Also adds a check to suppress the initial request or
subsequent requests if the bearer is blocked at the time the request is
scheduled for transmission.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:04:00 -04:00
Allan Stephens
3a777ff8b1 tipc: Enhance handling of discovery object creation failures
Modifies bearer creation and deletion code to improve handling of
scenarios when a neighbor discovery object cannot be created. The
creation routine now aborts the creation of a bearer if its discovery
object cannot be created, and deletes the newly created bearer, rather
than failing quietly and leaving an unusable bearer hanging around.

Since the exit via the goto label really isn't a definitive failure
in all cases, relabel it appropriately.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:59 -04:00
Allan Stephens
66e019a6af tipc: Strengthen checks for neighboring node discovery
Enhances existing checks on the discovery domain associated with a TIPC
bearer. A bearer can no longer be configured to accept links from itself
only (which would be pointless), or to nodes outside its own cluster
(since multi-cluster support has now been removed from TIPC). Also, the
neighbor discovery routine now validates link setup requests against the
configured discovery domain for the bearer, rather than simply ensuring
the requesting node belongs to the node's own cluster.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:55 -04:00
Allan Stephens
f9107ebe7d tipc: Don't respond to neighbor discovery request on blocked bearer
Adds a check to prevent TIPC from trying to respond to an incoming
LINK_CONFIG request message if the associated bearer is currently
prohibited from sending messages.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13 16:35:19 -04:00
Allan Stephens
d901a42b27 tipc: Eliminate unnecessary constant for neighbor discovery msg size
Eliminates an unnecessary constant that defines the size of a LINK_CONFIG
message, and uses one of the existing standard message size symbols in
its place. (The defunct constant was located in the wrong place anyway,
since it was grouped with other constants that define message users instead
of message sizes.)

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13 16:35:18 -04:00
Allan Stephens
37b9c08a88 tipc: Optimizations to link creation code
Enhances link creation code as follows:

1) Detects illegal attempts to add a requested link earlier in the
   link creation process. This prevents TIPC from wasting time
   initializing a link object it then throws away, and also eliminates
   the code needed to do the throwing away.

2) Passes in the node object associated with the requested link.
   This allows TIPC to eliminate a search to locate the node object,
   as well as code that attempted to create the node if it doesn't
   exist.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13 16:35:18 -04:00
Allan Stephens
fa2bae2d5b tipc: Give Tx of discovery responses priority over link messages
Delay releasing the node lock when processing a neighbor discovery
message until after the optional discovery response message has been
sent. This helps ensure that any link protocol messages sent by a
link endpoint created as a result of a neighbor discovery request
are received after the discovery response is received, thereby
giving the receiving node a chance to create a peer link endpoint to
consume those link protocol messages, if one does not already exist.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13 16:35:18 -04:00
Allan Stephens
a728750e4f tipc: Cosmetic changes to neighbor discovery logic
Reworks the appearance of the routine that processes incoming
LINK_CONFIG messages to keep the main logic flow at a consistent level
of indentation, and to add comments outlining the various phases involved
in processing each message. This rework is being done to allow upcoming
enhancements to this routine to be integrated more cleanly.

The diff isn't really readable, so know that it was a case of the
old code being like:

	tipc_disc_recv_msg(..)
	{
		if (in_own_cluster(orig)) {
			...
			lines and lines of stuff
			...
		}
	}

which is now replaced with the more sane:

	tipc_disc_recv_msg(..)
	{
		if (!in_own_cluster(orig))
			return;
		...
		lines and lines of stuff
		...
	}

Instances of spin locking within the reindented block were replaced with
the identical tipc_node_[un]lock() abstractions.  Note that all these
changes are cosmetic in nature, and do not change the way LINK_CONFIG
messages are processed.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-13 16:35:18 -04:00
Allan Stephens
2e07dda165 tipc: Remove unused message header field for requested number of links
Eliminates support for the "number of requested links" field in a neighbor
discovery message. This field was never used and has been removed from
the TIPC 2.0 protocol specification.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-02-23 18:05:22 -05:00