As per comment from David Miller, we try to make the buffer reassembly
function more resilient to user errors than it is today.
- We check that the "*buf" parameter always is set, since this is
mandatory input.
- We ensure that *buf->next always is set to NULL before linking in
the buffer, instead of relying of the caller to have done this.
- We ensure that the "tail" pointer in the head buffer's control
block is initialized to NULL when the first fragment arrives.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes the following sparse warnings:
net/tipc/socket.c:545:5: warning:
symbol 'tipc_sk_proto_rcv' was not declared. Should it be static?
net/tipc/socket.c:2015:5: warning:
symbol 'tipc_ioctl' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we run broadcast packets over dual bearers/interfaces, the
current transmission code is flipping bearers between each sent
packet, with the purpose of leveraging the double bandwidth
available. The receiving bclink is resequencing the packets if
needed, so all messages are delivered upwards from the broadcast
link in the correct order, even if they may arrive in concurrent
interrupts.
However, at the moment of delivery upwards to the socket, we release
all spinlocks (bclink_lock, node_lock), so it is still possible
that arriving messages bypass each other before they reach the socket
queue.
We fix this by applying the same technique we are using for unicast
traffic. We use a link selector (i.e., the last bit of sending port
number) to ensure that messages from the same sender socket always are
sent over the same bearer. This guarantees sequential delivery between
socket pairs, which is sufficient to satisfy the protocol spec, as well
as all known user requirements.
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>
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>
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>
In this commit, we convert the socket multicast send function to
directly call the new multicast/broadcast function (tipc_bclink_xmit2())
introduced in the previous commit. We do this instead of letting the
call go via the now obsolete tipc_port_mcast_xmit(), hence saving
a call level and some code complexity.
We also remove the initial destination lookup at the message sending
side, and replace that with an unconditional lookup at the receiving
side, including on the sending node itself. This makes the destination
lookup and message transfer more uniform than before.
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>
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>
In a previous commit series ("tipc: new unicast transmission code")
we introduced a new message sending function, tipc_link_xmit2(),
and moved the unicast data users over to use that function. We now
let the internal name table distributor do the same.
The interaction between the name distributor and the node/link
layer also becomes significantly simpler, so we can eliminate
the function tipc_link_names_xmit().
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>
If the 'next' pointer of the last fragment buffer in a message is not
zeroed before reassembly, we risk ending up with a corrupt message,
since the reassembly function itself isn't doing this.
Currently, when a buffer is retrieved from the deferred queue of the
broadcast link, the next pointer is not cleared, with the result as
described above.
This commit corrects this, and thereby fixes a bug that may occur when
long broadcast messages are transmitted across dual interfaces. The bug
has been present since 40ba3cdf54 ("tipc:
message reassembly using fragment chain")
This commit should be applied to both net and net-next.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a regression bug caused by:
067608e9d0 ("tipc: introduce direct
iovec to buffer chain fragmentation function")
If data is sent on a nonblocking socket and the destination link
is congested, the buffer chain is leaked. We fix this by freeing
the chain in this case.
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 37e22164a8 ("tipc: rename and
move message reassembly function") reassembly of long broadcast messages
has been broken. This is because we test for a non-NULL return value
of the *buf parameter as criteria for succesful reassembly. However, this
parameter is left defined even after reception of the first fragment,
when reassebly is still incomplete. This leads to a kernel crash as soon
as a the first fragment of a long broadcast message is received.
We fix this with this commit, by implementing a stricter behavior of the
function and its return values.
This commit should be applied to both net and net-next.
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Link state acks triggered from the receive path is done before
the last received packet have been processed by the link layer.
The effect of this is that the last received packet will not be
included in the ack. This causes problems if the link window is
set to TIPC_MIN_LINK_WIN, where the ack interval will be equal to
the link tolerance, and the link enters a stop-and-go behavior.
We move the ack logic to after link state processing, just before
the packet is delivered to higher layers.
Signed-off-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Carl Sigurjonsson <carl.sigurjonsson@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a consequence of the recently introduced serialized access
to the socket in commit 8d94168a761819d10252bab1f8de6d7b202c3baa
("tipc: same receive code path for connection protocol and data
messages") we can make a number of simplifications in the
detection and handling of connection congestion situations.
- We don't need to keep two counters, one for sent messages and one
for acked messages. There is no longer any risk for races between
acknowledge messages arriving in BH and data message sending
running in user context. So we merge this into one counter,
'sent_unacked', which is incremented at sending and subtracted
from at acknowledge reception.
- We don't need to set the 'congested' field in tipc_port to
true before we sent the message, and clear it when sending
is successful. (As a matter of fact, it was never necessary;
the field was set in link_schedule_port() before any wakeup
could arrive anyway.)
- We keep the conditions for link congestion and connection connection
congestion separated. There would otherwise be a risk that an arriving
acknowledge message may wake up a user sleeping because of link
congestion.
- We can simplify reception of acknowledge messages.
We also make some cosmetic/structural changes:
- We rename the 'congested' field to the more correct 'link_cong“.
- We rename 'conn_unacked' to 'rcv_unacked'
- We move the above mentioned fields from struct tipc_port to
struct tipc_sock.
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>
We simplify the code for receiving connection probes, leveraging the
recently introduced tipc_msg_reverse() function. We also stick to
the principle of sending a possible response message directly from
the calling (tipc_sk_rcv or backlog_rcv) functions, hence making
the call chain shallower and easier to follow.
We make one small protocol change here, allowed according to
the spec. If a protocol message arrives from a remote socket that
is not the one we are connected to, we are currently generating a
connection abort message and send it to the source. This behavior
is unnecessary, and might even be a security risk, so instead we
now choose to only ignore the message. The consequnce for the sender
is that he will need longer time to discover his mistake (until the
next timeout), but this is an extreme corner case, and may happen
anyway under other circumstances, so we deem this change acceptable.
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>
As a preparation to eliminate port_lock we need to bring reception
of connection protocol messages under proper protection of bh_lock_sock
or socket owner.
We fix this by letting those messages follow the same code path as
incoming data messages.
As a side effect of this change, the last reference to the function
net_route_msg() disappears, and we can eliminate that function.
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>
Several functions in port.c, related to the port protocol and
connection shutdown, need to send messages. We now convert them
to use the new link send function.
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>
We move the message sending across established connections
to use the message preparation and send functions introduced
earlier in this series. We now do the message preparation
and call to the link send function directly from the socket,
instead of going via the port layer.
As a consequence of this change, the functions tipc_send(),
tipc_port_iovec_rcv(), tipc_port_iovec_reject() and tipc_reject_msg()
become unreferenced and can be eliminated from port.c. For the same
reason, the functions tipc_link_xmit_fast(), tipc_link_iovec_xmit_long()
and tipc_link_iovec_fast() can be eliminated from link.c.
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>
We merge the code for sending port name and port identity addressed
messages into the corresponding send functions in socket.c, and start
using the new fragmenting and transmit functions we just have introduced.
This saves a call level and quite a few code lines, as well as making
this part of the code easier to follow. As a consequence, the functions
tipc_send2name() and tipc_send2port() in port.c can be removed.
For practical reasons, we break out the code for sending multicast messages
from tipc_sendmsg() and move it into a separate function, tipc_sendmcast(),
but we do not yet convert it into using the new build/send functions.
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>
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>
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>