Commit Graph

80 Commits

Author SHA1 Message Date
Jon Paul Maloy
dff29b1a88 tipc: eliminate delayed link deletion at link failover
When a bearer is disabled manually, all its links have to be reset
and deleted. However, if there is a remaining, parallel link ready
to take over a deleted link's traffic, we currently delay the delete
of the removed link until the failover procedure is finished. This
is because the remaining link needs to access state from the reset
link, such as the last received packet number, and any partially
reassembled buffer, in order to perform a successful failover.

In this commit, we do instead move the state data over to the new
link, so that it can fulfill the procedure autonomously, without
accessing any data on the old link. This means that we can now
proceed and delete all pertaining links immediately when a bearer
is disabled. This saves us from some unnecessary complexity in such
situations.

We also choose to change the confusing definitions CHANGEOVER_PROTOCOL,
ORIGINAL_MSG and DUPLICATE_MSG to the more descriptive TUNNEL_PROTOCOL,
FAILOVER_MSG and SYNCH_MSG respectively.

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>
2015-04-02 16:27:12 -04:00
Jon Paul Maloy
8b4ed8634f tipc: eliminate race condition at dual link establishment
Despite recent improvements, the establishment of dual parallel
links still has a small glitch where messages can bypass each
other. When the second link in a dual-link configuration is
established, part of the first link's traffic will be steered over
to the new link. Although we do have a mechanism to ensure that
packets sent before and after the establishment of the new link
arrive in sequence to the destination node, this is not enough.
The arriving messages will still be delivered upwards in different
threads, something entailing a risk of message disordering during
the transition phase.

To fix this, we introduce a synchronization mechanism between the
two parallel links, so that traffic arriving on the new link cannot
be added to its input queue until we are guaranteed that all
pre-establishment messages have been delivered on the old, parallel
link.

This problem seems to always have been around, but its occurrence is
so rare that it has not been noticed until recent intensive testing.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-25 14:05:56 -04:00
Jon Paul Maloy
3127a0200d tipc: clean up handling of link congestion
After the recent changes in message importance handling it becomes
possible to simplify handling of messages and sockets when we
encounter link congestion.

We merge the function tipc_link_cong() into link_schedule_user(),
and simplify the code of the latter. The code should now be
easier to follow, especially regarding return codes and handling
of the message that caused the situation.

In case the scheduling function is unable to pre-allocate a wakeup
message buffer, it now returns -ENOBUFS, which is a more correct
code than the previously used -EHOSTUNREACH.

Reviewed-by: Ying Xue <ying.xue@windriver.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-25 14:05:56 -04:00
Jon Paul Maloy
e3eea1eb47 tipc: clean up handling of message priorities
Messages transferred by TIPC are assigned an "importance priority", -an
integer value indicating how to treat the message when there is link or
destination socket congestion.

There is no separate header field for this value. Instead, the message
user values have been chosen in ascending order according to perceived
importance, so that the message user field can be used for this.

This is not a good solution. First, we have many more users than the
needed priority levels, so we end up with treating more priority
levels than necessary. Second, the user field cannot always
accurately reflect the priority of the message. E.g., a message
fragment packet should really have the priority of the enveloped
user data message, and not the priority of the MSG_FRAGMENTER user.
Until now, we have been working around this problem in different ways,
but it is now time to implement a consistent way of handling such
priorities, although still within the constraint that we cannot
allocate any more bits in the regular data message header for this.

In this commit, we define a new priority level, TIPC_SYSTEM_IMPORTANCE,
that will be the only one used apart from the four (lower) user data
levels. All non-data messages map down to this priority. Furthermore,
we take some free bits from the MSG_FRAGMENTER header and allocate
them to store the priority of the enveloped message. We then adjust
the functions msg_importance()/msg_set_importance() so that they
read/set the correct header fields depending on user type.

This small protocol change is fully compatible, because the code at
the receiving end of a link currently reads the importance level
only from user data messages, where there is no change.

Reviewed-by: Erik Hugne <erik.hugne@ericsson.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
Jon Paul Maloy
05dcc5aa4d tipc: split link outqueue
struct tipc_link contains one single queue for outgoing packets,
where both transmitted and waiting packets are queued.

This infrastructure is hard to maintain, because we need
to keep a number of fields to keep track of which packets are
sent or unsent, and the number of packets in each category.

A lot of code becomes simpler if we split this queue into a transmission
queue, where sent/unacknowledged packets are kept, and a backlog queue,
where we keep the not yet sent packets.

In this commit we do this separation.

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
Jon Paul Maloy
cf2157f88a tipc: move message validation function to msg.c
The function link_buf_validate() is in reality re-entrant and context
independent, and will in later commits be called from several locations.
Therefore, we move it to msg.c, make it outline and rename the it to
tipc_msg_validate().

We also redesign the function to make proper use of pskb_may_pull()

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
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
d0f91938be tipc: add ip/udp media type
The ip/udp bearer can be configured in a point-to-point
mode by specifying both local and remote ip/hostname,
or it can be enabled in multicast mode, where links are
established to all tipc nodes that have joined the same
multicast group. The multicast IP address is generated
based on the TIPC network ID, but can be overridden by
using another multicast address as remote ip.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-05 22:08:42 -05:00
Erik Hugne
91e2eb5684 tipc: rename media/msg related definitions
The TIPC_MEDIA_ADDR_SIZE and TIPC_MEDIA_ADDR_OFFSET names
are misleading, as they actually define the size and offset of
the whole media info field and not the address part. This patch
does not have any functional changes.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27 18:18:48 -05:00
Jon Paul Maloy
cb1b728096 tipc: eliminate race condition at multicast reception
In a previous commit in this series we resolved a race problem during
unicast message reception.

Here, we resolve the same problem at multicast reception. We apply the
same technique: an input queue serializing the delivery of arriving
buffers. The main difference is that here we do it in two steps.
First, the broadcast link feeds arriving buffers into the tail of an
arrival queue, which head is consumed at the socket level, and where
destination lookup is performed. Second, if the lookup is successful,
the resulting buffer clones are fed into a second queue, the input
queue. This queue is consumed at reception in the socket just like
in the unicast case. Both queues are protected by the same lock, -the
one of the input queue.

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 16:00:03 -08:00
Jon Paul Maloy
c637c10355 tipc: resolve race problem at unicast message reception
TIPC handles message cardinality and sequencing at the link layer,
before passing messages upwards to the destination sockets. During the
upcall from link to socket no locks are held. It is therefore possible,
and we see it happen occasionally, that messages arriving in different
threads and delivered in sequence still bypass each other before they
reach the destination socket. This must not happen, since it violates
the sequentiality guarantee.

We solve this by adding a new input buffer queue to the link structure.
Arriving messages are added safely to the tail of that queue by the
link, while the head of the queue is consumed, also safely, by the
receiving socket. Sequentiality is secured per socket by only allowing
buffers to be dequeued inside the socket lock. Since there may be multiple
simultaneous readers of the queue, we use a 'filter' parameter to reduce
the risk that they peek the same buffer from the queue, hence also
reducing the risk of contention on the receiving socket locks.

This solves the sequentiality problem, and seems to cause no measurable
performance degradation.

A nice side effect of this change is that lock handling in the functions
tipc_rcv() and tipc_bcast_rcv() now becomes uniform, something that
will enable future simplifications of those functions.

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 16:00:02 -08:00
Jon Paul Maloy
e3a77561e7 tipc: split up function tipc_msg_eval()
The function tipc_msg_eval() is in reality doing two related, but
different tasks. First it tries to find a new destination for named
messages, in case there was no first lookup, or if the first lookup
failed. Second, it does what its name suggests, evaluating the validity
of the message and its destination, and returning an appropriate error
code depending on the result.

This is confusing, and in this commit we choose to break it up into two
functions. A new function, tipc_msg_lookup_dest(), first attempts to find
a new destination, if the message is of the right type. If this lookup
fails, or if the message should not be subject to a second lookup, the
already existing tipc_msg_reverse() is called. This function performs
prepares the message for rejection, if applicable.

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 16:00:02 -08:00
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
Ying Xue
3474753954 tipc: make tipc node address support net namespace
If net namespace is supported in tipc, each namespace will be treated
as a separate tipc node. Therefore, every namespace must own its
private tipc node address. This means the "tipc_own_addr" global
variable of node address must be moved to tipc_net structure to
satisfy the requirement. It's turned out that users also can assign
node address for every namespace.

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

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:33 -05:00
Ying Xue
1da465683a tipc: make tipc broadcast link support net namespace
TIPC broadcast link is statically established and its relevant states
are maintained with the global variables: "bcbearer", "bclink" and
"bcl". Allowing different namespace to own different broadcast link
instances, these variables must be moved to tipc_net structure and
broadcast link instances would be allocated and initialized when
namespace is created.

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
859fc7c0ce tipc: cleanup core.c and core.h files
Only the works of initializing and shutting down tipc module are done
in core.h and core.c files, so all stuffs which are not closely
associated with the two tasks should be moved to appropriate places.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 16:24:31 -05:00
Ying Xue
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
Ying Xue
a6ca109443 tipc: use generic SKB list APIs to manage TIPC outgoing packet chains
Use standard SKB list APIs associated with struct sk_buff_head to
manage socket outgoing packet chain and name table outgoing packet
chain, having relevant code simpler and more readable.

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>
2014-11-26 12:30:17 -05:00
Ying Xue
58dc55f256 tipc: use generic SKB list APIs to manage link transmission queue
Use standard SKB list APIs associated with struct sk_buff_head to
manage link transmission queue, having relevant code more clean.

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>
2014-11-26 12:30:17 -05:00
Ying Xue
58311d1690 tipc: eliminate two pseudo message types of BUNDLE_OPEN and BUNDLE_CLOSED
The pseudo message types of BUNDLE_CLOSED as well as BUNDLE_OPEN are
used to flag whether or not more messages can be bundled into a data
packet in the outgoing transmission queue. Obviously, no more messages
can be appended after the packet has been sent and is waiting to be
acknowledged and deleted. These message types do in reality represent
a send-side local implementation flag, and are not defined as part of
the protocol. It is therefore safe to move it to to where it belongs,
that is, the control area (TIPC_SKB_CB) of the buffer.

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>
2014-11-26 12:30:17 -05:00
Al Viro
45dcc687f7 tipc_msg_build(): pass msghdr instead of its ->msg_iov
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 05:16:41 -05:00
Jon Paul Maloy
50100a5e39 tipc: use pseudo message to wake up sockets after link congestion
The current link implementation keeps a linked list of blocked ports/
sockets that is populated when there is link congestion. The purpose
of this is to let the link know which users to wake up when the
congestion abates.

This adds unnecessary complexity to the data structure and the code,
since it forces us to involve the link each time we want to delete
a socket. It also forces us to grab the spinlock port_lock within
the scope of node_lock. We want to get rid of this direct dependence,
as well as the deadlock hazard resulting from the usage of port_lock.

In this commit, we instead let the link keep list of a "wakeup" pseudo
messages for use in such situations. Those messages are sent to the
pending sockets via the ordinary message reception path, and wake up
the socket's owner when they are received.

This enables us to get rid of the 'waiting_ports' linked lists in struct
tipc_port that manifest this direct reference. As a consequence, we can
eliminate another BH entry into the socket, and hence the need to grab
port_lock. This is a further step in our effort to remove port_lock
altogether.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 11:18:33 -07:00
Jon Paul Maloy
1dd0bd2b14 tipc: introduce new function tipc_msg_create()
The function tipc_msg_init() has turned out to be of limited value
in many cases. It take too few parameters to be usable for creating
a complete message, it makes too many assumptions about what the
message should be used for, and it does not allocate any buffer to
be returned to the caller.

Therefore, we now introduce the new function tipc_msg_create(), which
takes all the parameters needed to create a full message, and returns
a buffer of the requested size. The new function will be very useful
for the changes we will be doing in later commits in this series.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-23 11:18:33 -07:00
Jon Paul Maloy
9fbfb8b120 tipc: rename temporarily named functions
After the previous commit, we can now give the functions with temporary
names, such as tipc_link_xmit2(), tipc_msg_build2() etc., their proper
names.

There are no functional changes in this commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 21:38:19 -07:00
Jon Paul Maloy
c4116e1057 tipc: remove unreferenced functions
We can now remove a number of functions which have become obsolete
and unreferenced through this commit series. There are no functional
changes in this commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 21:38:19 -07:00
Jon Paul Maloy
078bec826f tipc: add new functions for multicast and broadcast distribution
We add a new broadcast link transmit function in bclink.c and a new
receive function in socket.c. The purpose is to move the branching
between external and internal destination down to the link layer,
just as we have done with unicast in earlier commits. We also make
use of the new link-independent fragmentation support that was
introduced in an earlier commit series.

This gives a shorter and simpler code path, and makes it possible
to obtain copy-free buffer delivery to all node local destination
sockets.

The new transmission code is added in parallel with the existing one,
and will be used by the socket multicast send function in the next
commit in this series.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16 21:38:18 -07:00
Jon Paul Maloy
5a379074a7 tipc: introduce message evaluation function
When a message arrives in a node and finds no destination
socket, we may need to drop it, reject it, or forward it after
a secondary destination lookup. The latter two cases currently
results in a code path that is perceived as complex, because it
follows a deep call chain via obscure functions such as
net_route_named_msg() and net_route_msg().

We now introduce a function, tipc_msg_eval(), that takes the
decision about whether such a message should be rejected or
forwarded, but leaves it to the caller to actually perform
the indicated action.

If the decision is 'reject', it is still the task of the recently
introduced function tipc_msg_reverse() to take the final decision
about whether the message is rejectable or not. In the latter case
it drops the message.

As a result of this change, we can finally eliminate the function
net_route_named_msg(), and hence become independent of net_route_msg().

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27 12:50:55 -07:00
Jon Paul Maloy
8db1bae30b tipc: separate building and sending of rejected messages
The way we build and send rejected message is currenty perceived as
hard to follow, partly because we let the transmission go via deep
call chains through functions such as tipc_reject_msg() and
net_route_msg().

We want to remove those functions, and make the call sequences shallower
and simpler. For this purpose, we separate building and sending of
rejected messages. We build the reject message using the new function
tipc_msg_reverse(), and let the transmission go via the newly introduced
tipc_link_xmit2() function, as all transmission eventually will do. We
also ensure that all calls to tipc_link_xmit2() are made outside
port_lock/bh_lock_sock.

Finally, we replace all calls to tipc_reject_msg() with the two new
calls at all locations in the code that we want to keep. The remaining
calls are made from code that we are planning to remove, along with
tipc_reject_msg() itself.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27 12:50:55 -07:00
Jon Paul Maloy
067608e9d0 tipc: introduce direct iovec to buffer chain fragmentation function
Fragmentation at message sending is currently performed in two
places in link.c, depending on whether data to be transmitted
is delivered in the form of an iovec or as a big sk_buff. Those
functions are also tightly entangled with the send functions
that are using them.

We now introduce a re-entrant, standalone function, tipc_msg_build2(),
that builds a packet chain directly from an iovec. Each fragment is
sized according to the MTU value given by the caller, and is prepended
with a correctly built fragment header, when needed. The function is
independent from who is calling and where the chain will be delivered,
as long as the caller is able to indicate a correct MTU.

The function is tested, but not called by anybody yet. Since it is
incompatible with the existing tipc_msg_build(), and we cannot yet
remove that function, we have given it a temporary name.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27 12:50:55 -07:00
Jon Paul Maloy
4f1688b2c6 tipc: introduce send functions for chained buffers in link
The current link implementation provides several different transmit
functions, depending on the characteristics of the message to be
sent: if it is an iovec or an sk_buff, if it needs fragmentation or
not, if the caller holds the node_lock or not. The permutation of
these options gives us an unwanted amount of unnecessarily complex
code.

As a first step towards simplifying the send path for all messages,
we introduce two new send functions at link level, tipc_link_xmit2()
and __tipc_link_xmit2(). The former looks up a link to the message
destination, and if one is found, it grabs the node lock and calls
the second function, which works exclusively inside the node lock
protection. If no link is found, and the destination is on the same
node, it delivers the message directly to the local destination
socket.

The new functions take a buffer chain where all packet headers are
already prepared, and the correct MTU has been used. These two
functions will later replace all other link-level transmit functions.

The functions are not backwards compatible, so we have added them
as new functions with temporary names. They are tested, but have no
users yet. Those will be added later in this series.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-27 12:50:54 -07:00
Jon Paul Maloy
37e22164a8 tipc: rename and move message reassembly function
The function tipc_link_frag_rcv() is in reality a re-entrant generic
message reassemby function that has nothing in particular to do with
the link, where it is defined now. This becomes obvious when we see
the need to call the function from other places in the code.

In this commit rename it to tipc_buf_append() and move it to the file
msg.c. We also simplify its signature by moving the tail pointer to
the control block of the head buffer, hence making the head buffer
self-contained.

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
Erik Hugne
40ba3cdf54 tipc: message reassembly using fragment chain
When the first fragment of a long data data message is received on a link, a
reassembly buffer large enough to hold the data from this and all subsequent
fragments of the message is allocated. The payload of each new fragment is
copied into this buffer upon arrival. When the last fragment is received, the
reassembled message is delivered upwards to the port/socket layer.

Not only is this an inefficient approach, but it may also cause bursts of
reassembly failures in low memory situations. since we may fail to allocate
the necessary large buffer in the first place. Furthermore, after 100 subsequent
such failures the link will be reset, something that in reality aggravates the
situation.

To remedy this problem, this patch introduces a different approach. Instead of
allocating a big reassembly buffer, we now append the arriving fragments
to a reassembly chain on the link, and deliver the whole chain up to the
socket layer once the last fragment has been received. This is safe because
the retransmission layer of a TIPC link always delivers packets in strict
uninterrupted order, to the reassembly layer as to all other upper layers.
Hence there can never be more than one fragment chain pending reassembly at
any given time in a link, and we can trust (but still verify) that the
fragments will be chained up in the correct order.

Signed-off-by: Erik Hugne <erik.hugne@ericsson.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>
2013-11-07 18:30:11 -05:00
Ying Xue
9446b87add tipc: remove iovec length parameter from all sending functions
tipc_msg_build() now copies message data from iovec to skb_buff
using memcpy_fromiovecend(), which doesn't need to be passed the
iovec length to perform the copying.

So we remove the parameter indicating iovec length in all
functions where TIPC messages are built and sent.

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 13:20:42 -04:00
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
Ying Xue
f1733d7580 tipc: remove user_port instance from tipc_port structure
After the native API has been completely removed, the 'user_port'
field in struct tipc_port becomes unused, and can be removed.
As a consequence, the "usrmem" argument in tipc_msg_build() is no
longer needed, and so we remove that one too.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-17 15:53:00 -07:00
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
c74a46110f tipc: Remove duplicate check of message destination node
Eliminates a check in the processing of TIPC messages arriving from
off node that ensures the message is destined for this node, since this
check duplicates an earlier check. (The check would be necessary if TIPC
needed to be able to route incoming messages to another node, but the
elimination of multi-cluster support means that this never happens and
all incoming messages are consumed by the receiving node.)

Note: This change involves the elimination of a single "if" statement
with a large "then" clause; consequently, a significant number of lines
end up getting re-indented. In addition, a simple message header access
routine that is no longer referenced is eliminated. However, the only
functional change is the elimination of the single check described above.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2012-02-24 17:05:14 -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
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
741d9eb7b8 tipc: Cleanup of message header size terminology
Performs cosmetic cleanup of the symbolic names used to specify TIPC
payload message header sizes. The revised names now more accurately
reflect the payload messages in which they can appear. In addition,
several places where these payload message symbol names were being used
to create non-payload messages have been updated to use the proper
internal message symbolic name.

No functional changes are introduced by this rework.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-06-24 16:18:17 -04:00
Allan Stephens
7eb878ed8e tipc: Eliminate redundant masking in message header routines
Gets rid of unnecessary masking in two routines that set TIPC message
header fields. (The msg_set_bits() routine already takes care of
masking the new value to the correct size.)

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-06-24 16:18:15 -04:00
Allan Stephens
74d33b32de tipc: Eliminate message header routines for caching destination node
Gets rid of a pair of routines that provide support for temporarily
caching the destination node for a message in the associated message
buffer's application handle, since this capability is no longer used.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-06-24 16:18:15 -04:00
Allan Stephens
2689690469 tipc: Avoid recomputation of outgoing message length
Rework TIPC's message sending routines to take advantage of the total
amount of data value passed to it by the kernel socket infrastructure.
This change eliminates the need for TIPC to compute the size of outgoing
messages itself, as well as the check for an oversize message in
tipc_msg_build().  In addition, this change warrants an explanation:

   -     res = send_packet(NULL, sock, &my_msg, 0);
   +     res = send_packet(NULL, sock, &my_msg, bytes_to_send);

Previously, the final argument to send_packet() was ignored (since the
amount of data being sent was recalculated by a lower-level routine)
and we could just pass in a dummy value (0). Now that the
recalculation is being eliminated, the argument value being passed to
send_packet() is significant and we have to supply the actual amount
of data we want to send.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:57 -04:00
Allan Stephens
92138d1f25 tipc: Cosmetic consolidation of internal message type definitions
Half of the #define entries in msg.h were down at the bottom
of the header, instead of up at the top before any of the static
inlines etc.   Relocate them up to the top, to be consistent with
the other normal linux header file layout conventions.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:45 -04:00
Allan Stephens
19f53d2cef tipc: Eliminate unused routing message definitions
Gets rid of unused constants defining the types used in routing
messages. These messages no longer exist in TIPC now that multicluster
and multizone support has been eliminated.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:44 -04:00
Allan Stephens
cc4c4353f0 tipc: Update comments in message header include file
Removes comments in TIPC's message header include file that are
outdated and/or unnecessary. Also introduces short comments (or
supplements existing ones) to better describe several set of existing
symbolic constants.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-05-10 16:03:36 -04:00
Allan Stephens
390bce4237 tipc: Eliminate obsolete routine for handling routed messages
Eliminates a routine that is used in handling messages arriving from
another cluster or zone. Such messages can no longer be received by TIPC
now that multi-cluster and multi-zone network support has been eliminated.

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
7945c1fb02 tipc: Eliminate remaining support for routing table messages
Gets rid of all remaining code relating to ROUTE_DISTRIBUTOR messages.
These messages were only used in multi-cluster and multi-zone networks,
which TIPC no longer supports. (For safety, TIPC now treats such messages
the same way that it handles other unrecognized 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