Граф коммитов

94 Коммитов

Автор SHA1 Сообщение Дата
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 28dd94187a tipc: use bc_lock to protect node map in bearer structure
The node map variable - 'nodes' in bearer structure is only used by
bclink. When bclink accesses it, bc_lock is held. But when change it,
for instance, in tipc_bearer_add_dest() or tipc_bearer_remove_dest()
the bc_lock is not taken at all. To avoid any inconsistent data, we
should always grab bc_lock while accessing node map variable.

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
Ying Xue 4ae88c94d3 tipc: use bearer_disable to disable bearer in tipc_l2_device_event
As bearer pointer is known in tipc_l2_device_event(), it's unnecessary
to search it again in tipc_disable_bearer(). If tipc_disable_bearer()
is replaced with bearer_disable() in tipc_l2_device_event(), this will
help us save a bit time when bearer is disabled.

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
Ying Xue f1c8d8cb82 tipc: make media_ptr pointed netdevice valid
The 'media_ptr' pointer in bearer structure which points to network
device, is protected by RCU. So, before netdevice is released,
synchronize_net() should be involved to prevent no any user of
the netdevice on read side from accessing it after it is freed.

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
Ying Xue 7216cd949c tipc: purge tipc_net_lock lock
Now tipc routing hierarchy comprises the structures 'node', 'link'and
'bearer'. The whole hierarchy is protected by a big read/write lock,
tipc_net_lock, to ensure that nothing is added or removed while code
is accessing any of these structures. Obviously the locking policy
makes node, link and bearer components closely bound together so that
their relationship becomes unnecessarily complex. In the worst case,
such locking policy not only has a negative influence on performance,
but also it's prone to lead to deadlock occasionally.

In order o decouple the complex relationship between bearer and node
as well as link, the locking policy is adjusted as follows:

- Bearer level
  RTNL lock is used on update side, and RCU is used on read side.
  Meanwhile, all bearer instances including broadcast bearer are
  saved into bearer_list array.

- Node and link level
  All node instances are saved into two tipc_node_list and node_htable
  lists. The two lists are protected by node_list_lock on write side,
  and they are guarded with RCU lock on read side. All members in node
  structure including link instances are protected by node spin lock.

- The relationship between bearer and node
  When link accesses bearer, it first needs to find the bearer with
  its bearer identity from the bearer_list array. When bearer accesses
  node, it can iterate the node_htable hash list with the node
  address to find the corresponding node.

In the new locking policy, every component has its private locking
solution and the relationship between bearer and node is very simple,
that is, they can find each other with node address or bearer identity
from node_htable hash list or bearer_list array.

Until now above all changes have been done, so tipc_net_lock can be
removed safely.

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
Ying Xue 2231c5af45 tipc: use RCU to protect media_ptr pointer
Now the media_ptr pointer is protected with tipc_net_lock write lock
on write side; tipc_net_lock read lock is used to read side. As the
part of effort of eliminating tipc_net_lock, we decide to adjust the
locking policy of media_ptr pointer protection: on write side, RTNL
lock is use while on read side RCU read lock is applied.

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
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
Ying Xue f8322dfce5 tipc: convert bearer_list to RCU list
Convert bearer_list to RCU list. It's protected by RTNL lock on
update side, and RCU read lock is applied to read side.

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 21:17:52 -04:00
Ying Xue ca07fb07c9 tipc: adjust locking policy of protecting tipc_ptr pointer of net_device
Currently the 'tipc_ptr' pointer is protected by tipc_net_lock
write lock on write side, and RCU read lock is applied to read
side. In addition, there have two paths on write side where we
may change variables pointed by the 'tipc_ptr' pointer: one is
to configure bearer by tipc-config tool and another one is that
bearer status is changed by notification events of its attached
interface. But on the latter path, we improperly deem that
accessing 'tipc_ptr' pointer happens on read side with
rcu_read_lock() although some variables pointed by the 'tipc_ptr'
pointer are changed possibly.

Moreover, as now the both paths are guarded by RTNL lock, it's
better to adjust the locking policy of 'tipc_ptr' pointer
protection, allowing RTNL instead of tipc_net_lock write lock to
protect it on write side, which will help us purge tipc_net_lock
in the future.

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 21:17:52 -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
Erik Hugne a21a584d67 tipc: fix neighbor detection problem after hw address change
If the hardware address of a underlying netdevice is changed, it is
not enough to simply reset the bearer/links over this device. We
also need to reflect this change in the TIPC bearer and node
discovery structures aswell.

This patch adds the necessary reinitialization of the node disovery
mechanism following a hardware address change so that the correct
originating media address is advertised in the discovery messages.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Reported-by: Dong Liu <dliu.cn@gmail.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 987b58be37 tipc: make broadcast bearer store in bearer_list array
Now unicast bearer is dynamically allocated and placed into its
identity specified slot of bearer_list array. When we search
bearer_list array with a bearer identity, the corresponding bearer
instance can be found. But broadcast bearer is statically allocated
and it is not located in the bearer_list array yet. So we decide to
enlarge bearer_list array into MAX_BEARERS + 1 slots, and its last
slot stores the broadcast bearer so that the broadcast bearer can
be found from bearer_list array with MAX_BEARERS as index. The
change will help us reduce the complex relationship between bearer
and link in the future.

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>
2014-03-27 13:08:37 -04:00
Ying Xue f47de12b06 tipc: remove active flag from tipc_bearer structure
After the allocation of tipc_bearer structure instance is converted
from statical way to dynamical way, we identify whether a certain
tipc_bearer structure pointer is valid by checking whether the pointer
is NULL or not. So the active flag in tipc_bearer structure becomes
redundant.

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>
2014-03-27 13:08:37 -04:00
Ying Xue 3874ccbba8 tipc: convert tipc_bearers array to pointer list
As part of the effort to introduce RCU protection for the bearer
list, we first need to change it to a list of pointers.

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>
2014-03-27 13:08:37 -04:00
Joe Perches 184593c734 tipc: Convert uses of __constant_<foo> to <foo>
The use of __constant_<foo> has been unnecessary for quite awhile now.

Make these uses consistent with the rest of the kernel.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-12 15:28:06 -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 a83045292d tipc: remove bearer_lock from tipc_bearer struct
After the earlier commits ("tipc: remove 'links' list from
tipc_bearer struct") and ("tipc: introduce new spinlock to protect
struct link_req"), there is no longer any need to protect struct
link_req or or any link list by use of bearer_lock. Furthermore,
we have eliminated the need for using bearer_lock during downcalls
(send) from the link to the bearer, since we have ensured that
bearers always have a longer life cycle that their associated links,
and always contain valid data.

So, the only need now for a lock protecting bearers is for guaranteeing
consistency of the bearer list itself. For this, it is sufficient, at
least for the time being, to continue applying 'net_lock´ in write mode.

By removing bearer_lock we also pre-empt introduction of issue b) descibed
in the previous commit "tipc: remove 'links' list from tipc_bearer struct":

"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".

Therefore, we now eliminate the bearer_lock spinlock.

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 17:57:07 -05:00
Jon Paul Maloy 7d33939f47 tipc: delay delete of link when failover is needed
When a bearer is disabled, all its attached links are deleted.
Ideally, we should do link failover to redundant links on other bearers,
if there are any, in such cases. This would be consistent with current
behavior when a link is reset, but not deleted. However, due to the
complexity involved, and the (wrongly) perceived low demand for this
feature, it was never implemented until now.

We mark the doomed link for deletion with a new flag, but wait until the
failover process is finished before we actually delete it. With the
improved link tunnelling/failover code introduced earlier in this commit
series, it is now easy to identify a spot in the code where the failover
is finished and it is safe to delete the marked link. Moreover, the test
for the flag and the deletion can be done synchronously, and outside the
most time critical data path.

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>
2014-02-13 17:57:07 -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
Ying Xue 8d8439b686 tipc: move code for deleting links from bearer.c to link.c
We break out the code for deleting attached links in the
function bearer_disable(), and define a new function named
tipc_link_delete_list() to do this job.

This commit incurs no functional changes, but makes the code of
function bearer_disable() cleaner. It is also a preparation
for a more important change to the bearer code, in a subsequent
commit in this 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>
2014-02-13 17:57:05 -05:00
Ying Xue e0ca2c30b1 tipc: move code for resetting links from bearer.c to link.c
We break out the code for resetting attached links in the
function tipc_reset_bearer(), and define a new function named
tipc_link_reset_list() to do this job.

This commit incurs no functional changes, but makes the code
of function tipc_reset_bearer() cleaner. It is also a preparation
for a more important change to the bearer code, in a subsequent
commit in this 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>
2014-02-13 17:57:05 -05:00
stephen hemminger 963a185539 tipc: spelling fixes
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14 18:18:22 -08:00
Jon Paul Maloy 170b3927b4 tipc: rename functions related to link failover and improve comments
The functionality related to link addition and failover is unnecessarily
hard to understand and maintain. We try to improve this by renaming
some of the functions, at the same time adding or improving the
explanatory comments around them. Names such as "tipc_rcv()" etc. also
align better with what is used in other networking components.

The changes in this commit are purely cosmetic, no functional changes
are made.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07 18:44:25 -05:00
stephen hemminger eec73f1c96 tipc: remove unused code
Remove dead code;
       tipc_bearer_find_interface
       tipc_node_redundant_links

This may break out of tree version of TIPC if there still is one.
But that maybe a good thing :-)

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-04 20:18:50 -05:00
Ying Xue e4d050cbf7 tipc: eliminate code duplication in media layer
Currently TIPC supports two L2 media types, Ethernet and Infiniband.
Because both these media are accessed through the common net_device API,
several functions in the two media adaptation files turn out to be
fully or almost identical, leading to unnecessary code duplication.

In this commit we extract this common code from the two media files
and move them to the generic bearer.c. Additionally, we change
the function names to reflect their real role: to access L2 media,
irrespective of type.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Cc: Patrick McHardy <kaber@trash.net>
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>
2013-12-11 00:17:43 -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 ef72a7e02a tipc: improve naming and comment consistency in media layer
struct 'tipc_media' represents the specific info that the media
layer adaptors (eth_media and ib_media) expose to the generic
bearer layer. We clarify this by improved commenting, and by giving
the 'media_list' array the more appropriate name 'media_info_array'.

There are no functional changes in this commit.

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>
2013-12-11 00:17:42 -05:00
Jon Paul Maloy 5702dbab68 tipc: initiate media type array at compile time
Communication media types are abstracted through the struct 'tipc_media',
one per media type. These structs are allocated statically inside their
respective media file.

Furthermore, in order to be able to reach all instances from a central
location, we keep a static array with pointers to these structs. This
array is currently initialized at runtime, under protection of
tipc_net_lock. However, since the contents of the array itself never
changes after initialization, we can just as well initialize it at
compile time and make it 'const', at the same time making it obvious
that no lock protection is needed here.

This commit makes the array constant and removes the redundant lock
protection.

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>
2013-12-11 00:17:42 -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
Ying Xue f2875c3cc4 tipc: avoid unnecessary lookup for tipc bearer instance
tipc_block_bearer() currently takes a bearer name (const char*)
as argument. This requires the function to make a lookup to find
the pointer to the corresponding bearer struct. In the current
code base this is not necessary, since the only two callers
(tipc_continue(),recv_notification()) already have validated
copies of this pointer, and hence can pass it directly in the
function call.

We change tipc_block_bearer() to directly take struct tipc_bearer*
as argument instead.

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>
2013-10-18 13:20:43 -04:00
Ying Xue 4babbaa8a1 tipc: make bearer and media naming consistent
TIPC 'bearer' exists as an abstract concept, while 'media'
is deemed a specific implementation of a bearer, such as Ethernet
or Infiniband media. When a component inside TIPC wants to control
a specific media, it only needs to access the generic bearer API
to achieve this. However, in the current media implementations,
the 'bearer' name is also extensively used in media specific
function and variable names.

This may create confusion, so we choose to replace the term 'bearer'
with 'media' in all function names, variable names, and prefixes
where this is what really is meant.

Note that this change is cosmetic only, and no runtime behaviour
changes are made here.

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>
2013-10-18 13:20:43 -04:00
dingtianhong d4cca39d90 tipc: avoid possible deadlock while enable and disable bearer
We met lockdep warning when enable and disable the bearer for commands such as:

tipc-config -netid=1234 -addr=1.1.3 -be=eth:eth0
tipc-config -netid=1234 -addr=1.1.3 -bd=eth:eth0

---------------------------------------------------

[  327.693595] ======================================================
[  327.693994] [ INFO: possible circular locking dependency detected ]
[  327.694519] 3.11.0-rc3-wwd-default #4 Tainted: G           O
[  327.694882] -------------------------------------------------------
[  327.695385] tipc-config/5825 is trying to acquire lock:
[  327.695754]  (((timer))#2){+.-...}, at: [<ffffffff8105be80>] del_timer_sync+0x0/0xd0
[  327.696018]
[  327.696018] but task is already holding lock:
[  327.696018]  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>] bearer_disable+  0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] which lock already depends on the new lock.
[  327.696018]
[  327.696018]
[  327.696018] the existing dependency chain (in reverse order) is:
[  327.696018]
[  327.696018] -> #1 (&(&b_ptr->lock)->rlock){+.-...}:
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff814d65b1>] _raw_spin_lock_bh+0x41/0x80
[  327.696018]        [<ffffffffa02c5d48>] disc_timeout+0x18/0xd0 [tipc]
[  327.696018]        [<ffffffff8105b92a>] call_timer_fn+0xda/0x1e0
[  327.696018]        [<ffffffff8105bcd7>] run_timer_softirq+0x2a7/0x2d0
[  327.696018]        [<ffffffff8105379a>] __do_softirq+0x16a/0x2e0
[  327.696018]        [<ffffffff81053a35>] irq_exit+0xd5/0xe0
[  327.696018]        [<ffffffff81033005>] smp_apic_timer_interrupt+0x45/0x60
[  327.696018]        [<ffffffff814df4af>] apic_timer_interrupt+0x6f/0x80
[  327.696018]        [<ffffffff8100b70e>] arch_cpu_idle+0x1e/0x30
[  327.696018]        [<ffffffff810a039d>] cpu_idle_loop+0x1fd/0x280
[  327.696018]        [<ffffffff810a043e>] cpu_startup_entry+0x1e/0x20
[  327.696018]        [<ffffffff81031589>] start_secondary+0x89/0x90
[  327.696018]
[  327.696018] -> #0 (((timer))#2){+.-...}:
[  327.696018]        [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]        [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]        [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]        [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]        [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]        [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]        [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]        [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]        [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]        [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]        [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]        [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]        [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]        [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]        [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]        [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]        [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]        [<ffffffff814de852>] system_call_fastpath+0x16/0x1b
[  327.696018]
[  327.696018] other info that might help us debug this:
[  327.696018]
[  327.696018]  Possible unsafe locking scenario:
[  327.696018]
[  327.696018]        CPU0                    CPU1
[  327.696018]        ----                    ----
[  327.696018]   lock(&(&b_ptr->lock)->rlock);
[  327.696018]                                lock(((timer))#2);
[  327.696018]                                lock(&(&b_ptr->lock)->rlock);
[  327.696018]   lock(((timer))#2);
[  327.696018]
[  327.696018]  *** DEADLOCK ***
[  327.696018]
[  327.696018] 5 locks held by tipc-config/5825:
[  327.696018]  #0:  (cb_lock){++++++}, at: [<ffffffff8143e608>] genl_rcv+0x18/0x40
[  327.696018]  #1:  (genl_mutex){+.+.+.}, at: [<ffffffff8143ed66>] genl_rcv_msg+0xa6/0xd0
[  327.696018]  #2:  (config_mutex){+.+.+.}, at: [<ffffffffa02bf889>] tipc_cfg_do_cmd+0x39/ 0x550 [tipc]
[  327.696018]  #3:  (tipc_net_lock){++.-..}, at: [<ffffffffa02be738>] tipc_disable_bearer+ 0x18/0x60 [tipc]
[  327.696018]  #4:  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>]             bearer_disable+0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] stack backtrace:
[  327.696018] CPU: 2 PID: 5825 Comm: tipc-config Tainted: G           O 3.11.0-rc3-wwd-    default #4
[  327.696018] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  327.696018]  00000000ffffffff ffff880037fa77a8 ffffffff814d03dd 0000000000000000
[  327.696018]  ffff880037fa7808 ffff880037fa77e8 ffffffff810b1c4f 0000000037fa77e8
[  327.696018]  ffff880037fa7808 ffff880037e4db40 0000000000000000 ffff880037e4e318
[  327.696018] Call Trace:
[  327.696018]  [<ffffffff814d03dd>] dump_stack+0x4d/0xa0
[  327.696018]  [<ffffffff810b1c4f>] print_circular_bug+0x10f/0x120
[  327.696018]  [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]  [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]  [<ffffffff81087a28>] ? sched_clock_cpu+0xd8/0x110
[  327.696018]  [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]  [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]  [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]  [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]  [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]  [<ffffffff81218783>] ? security_capable+0x13/0x20
[  327.696018]  [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]  [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]  [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]  [<ffffffff8143ecc0>] ? genl_lock+0x20/0x20
[  327.696018]  [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]  [<ffffffff8143e608>] ? genl_rcv+0x18/0x40
[  327.696018]  [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]  [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]  [<ffffffff81289d7c>] ? memcpy_fromiovec+0x6c/0x90
[  327.696018]  [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]  [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]  [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]  [<ffffffff813fe29c>] ? release_sock+0x8c/0xa0
[  327.696018]  [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]  [<ffffffff8117fa24>] ? rw_verify_area+0x54/0x100
[  327.696018]  [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]  [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]  [<ffffffff814de852>] system_call_fastpath+0x16/0x1b

-----------------------------------------------------------------------

The problem is that the tipc_link_delete() will cancel the timer disc_timeout() when
the b_ptr->lock is hold, but the disc_timeout() still call b_ptr->lock to finish the
work, so the dead lock occurs.

We should unlock the b_ptr->lock when del the disc_timeout().

Remove link_timeout() still met the same problem, the patch:

http://article.gmane.org/gmane.network.tipc.general/4380

fix the problem, so no need to send patch for fix link_timeout() deadlock warming.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-11 21:58:41 -07:00
Patrick McHardy a29a194a15 tipc: add InfiniBand media type
Add InfiniBand media type based on the ethernet media type.

The only real difference is that in case of InfiniBand, we need the entire
20 bytes of space reserved for media addresses, so the TIPC media type ID is
not explicitly stored in the packet payload.

Sample output of tipc-config:

# tipc-config -v -addr -netid -nt=all -p -m -b -n -ls

node address: <10.1.4>
current network id: 4711
Type       Lower      Upper      Port Identity              Publication Scope
0          167776257  167776257  <10.1.1:1855512577>        1855512578  cluster
           167776260  167776260  <10.1.4:1216454657>        1216454658  zone
1          1          1          <10.1.4:1216479235>        1216479236  node
Ports:
1216479235: bound to {1,1}
1216454657: bound to {0,167776260}
Media:
eth
ib
Bearers:
ib:ib0
Nodes known:
<10.1.1>: up
Link <broadcast-link>
  Window:20 packets
  RX packets:0 fragments:0/0 bundles:0/0
  TX packets:0 fragments:0/0 bundles:0/0
  RX naks:0 defs:0 dups:0
  TX naks:0 acks:0 dups:0
  Congestion bearer:0 link:0  Send queue max:0 avg:0

Link <10.1.4:ib0-10.1.1:ib0>
  ACTIVE  MTU:2044  Priority:10  Tolerance:1500 ms  Window:50 packets
  RX packets:80 fragments:0/0 bundles:0/0
  TX packets:40 fragments:0/0 bundles:0/0
  TX profile sample:22 packets  average:54 octets
  0-64:100% -256:0% -1024:0% -4096:0% -16384:0% -32768:0% -66000:0%
  RX states:410 probes:213 naks:0 defs:0 dups:0
  TX states:410 probes:197 naks:0 acks:0 dups:0
  Congestion bearer:0 link:0  Send queue max:1 avg:0

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
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
Ying Xue 381294331e tipc: manually inline single use media_name_valid routine
After eliminating the mechanism which checks whether all letters
in media name string are within a given character set, the
media_name_valid routine becomes trivial.  It is also only
used once, so it is unnecessary to keep it as a separate function.

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>
2012-08-20 02:26:30 -07:00
Ying Xue fc0739385b tipc: remove pointless name sanity check and tipc_alphabet array
There is no real reason to check whether all letters in the given
media name and network interface name are within the character set
defined in tipc_alphabet array. Even if we eliminate the checking,
the rest of checking conditions in tipc_enable_bearer() can ensure
we do not enable an invalid or illegal bearer.

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>
2012-08-20 02:26:30 -07:00
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
Ben Hutchings 2c53040f01 net: Fix (nearly-)kernel-doc comments for various functions
Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-10 23:13:45 -07:00
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 336ebf5bf5 tipc: Add routines for safe checking of node's network address
Introduces routines that test whether a given network address is
equal to a node's own network address or if it lies within the node's
own network cluster, and which work properly regardless of whether
the node is using the default network address <0.0.0> or a non-zero
network address that is assigned later on. In essence, these routines
ensure that address <0.0.0> is treated as an alias for "this node",
regardless of which network address the node is actually using.

Old users of the pre-existing more strict match in_own_cluster()
have been accordingly redirected to what is now called
in_own_cluster_exact() --- which does not extend matching to <0,0,0>.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-04-19 15:46:39 -04:00
Allan Stephens b58343f9ea tipc: Eliminate support for tipc_mode global variable
Removes all references to the global variable that records whether
TIPC is running in "single node" mode or "network" mode, since this
information can be easily deduced from the global variable that
records TIPC's network address. (i.e. a non-zero network address
means that TIPC is running in network mode.)

The changes made update most existing mode-based checks to use the
network address global variable. A few checks that are no longer
needed are removed entirely, along with any associated code lying on
non-executable control paths.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:17 -05:00
Allan Stephens 9efde4a0bd tipc: Eliminate a test for negative unsigned quantities
Simplifies a comparison operation to eliminate a useless test that
checks if an unsigned value is less than zero.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:15 -05:00
Paul Gortmaker f19765f4f7 tipc: rename struct bearer_name to struct tipc_bearer_names
The addition of the "s" to indicate pluralization is intentional,
since the struct actually contains two name variants.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-29 21:53:30 -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
Paul Gortmaker 358a0d1c9e tipc: rename struct media to struct tipc_media
Give it a meaningful prefix, as suggested by DaveM, so that it
is consistent with things like struct tipc_bearer, and so it isn't
confused with anything else.  This has no impact on the actual
runtime code behaviour.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-12-29 21:53:29 -05:00
Allan Stephens 5c216e1d28 tipc: Allow run-time alteration of default link settings
Permits run-time alteration of default link settings on a per-media
and per-bearer basis, in addition to the existing per-link basis.
The following syntax can now be used:

    tipc-config -lt=<link-name|bearer-name|media-name>/<tolerance>
    tipc-config -lp=<link-name|bearer-name|media-name>/<priority>
    tipc-config -lw=<link-name|bearer-name|media-name>/<window>

Note that changes to the default settings for a given media type has
no effect on the default settings used by existing bearers. Similarly,
changes to default bearer settings has no effect on existing link
endpoints that utilize that interface.

Thanks to Florian Westphal <fw@strlen.de> 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>
2011-12-27 11:33:39 -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