Relocates information about the size of TIPC's node table index and
its associated hash function, since only node subsystem routines need
to have access to this information.
Note that these changes are essentially cosmetic in nature, and have
no impact on the actual operation of TIPC.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
This "shortform" is actually longer than typing out what it is really
trying to do, and just makes reading the code more difficult, so
lets simply shoot it in the head.
In the case of log.c - the comparison is on a u32, so we can drop the
check for < 0 at the same time.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Adds a new check to TIPC's name table logic to reject any attempt to
create a new name publication that is identical to an existing one.
(Such an attempt will never happen under normal circumstances, but
could arise if another network node malfunctions and issues a duplicate
name publication message.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Streamlines the logic that prevents an application from binding a
reserved TIPC name type to a port by moving the check to the code
that handles a socket bind() operation. This allows internal TIPC
subsystems to bind a reserved name without having to set an atomic
flag to gain permission to use such a name. (This simplification is
now possible due to the elimination of support for TIPC's native API.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Utilizes the new "node signature" field in neighbor discovery messages
to ensure that all links TIPC associates with a given <Z.C.N> network
address belong to the same neighboring node. (Previously, TIPC could not
tell if link setup requests arriving on different interfaces were from
the same node or from two different nodes that has mistakenly been assigned
the same network address.)
The revised algorithm for detecting a duplicate node considers both the
node signature and the network interface adddress specified in a request
message when deciding how to respond to a link setup request. This prevents
false alarms that might otherwise arise during normal network operation
under the following scenarios:
a) A neighboring node reboots. (The node's signature changes, but the
network interface address remains unchanged.)
b) A neighboring node's network interface is replaced. (The node's signature
remains unchanged, but the network interface address changes.)
c) A neighboring node is completely replaced. (The node's signature and
network interface address both change.)
The algorithm also handles cases in which a node reboots and re-establishes
its links to TIPC (or begins re-establishing those links) before TIPC
detects that it is using a new node signature. In such cases of "delayed
rediscovery" TIPC simply accepts the new signature without disrupting
communication that is already underway over the links.
Thanks to Laser [gotolaser@gmail.com] for his contributions to the
development of this enhancement.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Modifies message rejection logic so that TIPC doesn't attempt to
send a FIN message to the rejecting port if it is known in advance
that there is no such message because the rejecting port doesn't exist.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Removes code that alters the publication key of a name table entry
that is being forcibly purged from TIPC's name table after contact
with the publishing node has been lost.
Current TIPC ensures that all defunct names are purged before
re-establishing contact with a failed node. There used to be a risk
that the publication might be accidentally deleted because it might be
re-added to the name table before the purge operation was completed.
But now there is no longer a need to ensure that the new key is different
than the old one.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies broadcast link so that an incoming fragmented message is not
lost if reassembly cannot begin because there currently is no buffer
big enough to hold the entire reassembled message. The broadcast link
now ignores the first fragment completely, which causes the sending node
to retransmit the first fragment so that reassembly can be re-attempted.
Previously, the sender would have had no reason to retransmit the 1st
fragment, so we would never have a chance to re-try the allocation.
To do this cleanly without duplicaton, a new bclink_accept_pkt()
function is introduced.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies unicast link endpoint logic so an incoming fragmented message
is not lost if reassembly cannot begin because there is no buffer big
enough to hold the entire reassembled message. The link endpoint now
ignores the first fragment completely, which causes the sending node to
retransmit the first fragment so that reassembly can be re-attempted.
Previously, the sender would have had no reason to retransmit the 1st
fragment, so we would never have a chance to re-try the allocation.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Eliminates support for the broadcast tag field, which is no longer
used by broadcast link NACK messages.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Completely redesigns broadcast link ACK and NACK mechanisms to prevent
spurious retransmit requests in dual LAN networks, and to prevent the
broadcast link from stalling due to the failure of a receiving node to
acknowledge receiving a broadcast message or request its retransmission.
Note: These changes only impact the timing of when ACK and NACK messages
are sent, and not the basic broadcast link protocol itself, so inter-
operability with nodes using the "classic" algorithms is maintained.
The revised algorithms are as follows:
1) An explicit ACK message is still sent after receiving 16 in-sequence
messages, and implicit ACK information continues to be carried in other
unicast link message headers (including link state messages). However,
the timing of explicit ACKs is now based on the receiving node's absolute
network address rather than its relative network address to ensure that
the failure of another node does not delay the ACK beyond its 16 message
target.
2) A NACK message is now typically sent only when a message gap persists
for two consecutive incoming link state messages; this ensures that a
suspected gap is not confirmed until both LANs in a dual LAN network have
had an opportunity to deliver the message, thereby preventing spurious NACKs.
A NACK message can also be generated by the arrival of a single link state
message, if the deferred queue is so big that the current message gap
cannot be the result of "normal" mis-ordering due to the use of dual LANs
(or one LAN using a bonded interface). Since link state messages typically
arrive at different nodes at different times the problem of multiple nodes
issuing identical NACKs simultaneously is inherently avoided.
3) Nodes continue to "peek" at NACK messages sent by other nodes. If
another node requests retransmission of a message gap suspected (but not
yet confirmed) by the peeking node, the peeking node forgets about the
gap and does not generate a duplicate retransmit request. (If the peeking
node subsequently fails to receive the lost message, later link state
messages will cause it to rediscover and confirm the gap and send another
NACK.)
4) Message gap "equality" is now determined by the start of the gap only.
This is sufficient to deal with the most common cases of message loss,
and eliminates the need for complex end of gap computations.
5) A peeking node no longer tries to determine whether it should send a
complementary NACK, since the most common cases of message loss don't
require it to be sent. Consequently, the node no longer examines the
"broadcast tag" field of a NACK message when peeking.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensures that all attempts to update broadcast link statistics are done
only while holding the lock that protects the link's main data structures,
to prevent interference by simultaneous updates caused by messages
arriving on other interfaces.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies broadcast link so that it increments the "received duplicate
message" count if an incoming message cannot be added to the deferred
message queue because it is already present in the queue. (The aligns
broadcast link behavior with that of TIPC's unicast links.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fixes a pair of problems in broadcast link message reception code
relating to the reclamation of the node lock after consuming an
in-sequence message.
1) Now retests to see if the sending node is still up after reclaiming
the node lock, and bails out if it is non-operational.
2) Now manipulates the node's deferred message queue only after
reclaiming the node lock, rather than using queue head pointer
information that was cached previously.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensures that any attempt to send a NACK message over TIPC's broadcast
link has exclusive access to the link's main data structures, to prevent
interference with a simultaneous attempt to send other broadcast link
traffic (such as application-generated multicast messages).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Corrects a problem in which a link endpoint that activates as the
result of receiving a RESET/STATE sequence of link protocol messages
fails to properly record the broadcast link status information about
the node to which it is now communicating with. (The problem does
not occur with the more common RESET/ACTIVATE sequence of messages.)
The fix ensures that the broadcast link status info is updated after
the RESET message resets the link endpoint, rather than before, thereby
preventing new information from being overwritten by the reset operation.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fix a bug that can prevent TIPC from sending broadcast messages to a node
if contact with the node is lost and then regained. The problem occurs if
the broadcast link first clears the flag indicating the node is part of the
link's distribution set (when it loses contact with the node), and later
fails to restore the flag (when contact is regained); restoration fails
if contact with the node is regained by implicit unicast link activation
triggered by the arrival of a data message, rather than explicitly by the
arrival of a link activation message.
The broadcast link now uses separate fields to track whether a node is
theoretically capable of receiving broadcast messages versus whether it is
actually part of the link's distribution set. The former member is updated
by the receipt of link protocol messages, which can occur at any time; the
latter member is updated only when contact with the node is gained or lost.
This change also permits the simplification of several conditional
expressions since the broadcast link's "supported" field can now only be
set if there are working links to the associated node.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensure that sequence number information about incoming broadcast link
messages is initialized only by the activation of the first link to a
given cluster node. Previously, a race condition allowed reset and/or
activation messages for a second link to re-initialize this sequence
number information with obsolete values. This could trigger TIPC to
request the retransmission of previously acknowledged broadcast link
messages from that node, resulting in broadcast link processing becoming
stalled if the node had already released one or more of those messages
and was unable to perform the required retransmission.
Thanks to Laser <gotolaser@gmail.com> for identifying this problem
and assisting in the development of this fix.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Ensures that a link endpoint discards any previously deferred link
protocol message whenever it attempts to send a new one.
Previously, it was possible for a link protocol message that was unsent
due to congestion to be transmitted after newer protocol messages had
been sent. The stale link protocol message might then cause the receiving
link endpoint to malfunction because of its outdated conent.
Thanks to Osamu Kaminuma [okaminum@avaya.com] for diagnosing the problem
and contributing a prototype patch.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Re-code the algorithm for inserting an out-of-sequence message into
a unicast or broadcast link's deferred message queue. It remains
functionally equivalent but should be easier to understand/maintain.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
This changes both the struct bcbearer and struct bcbearer_pair to
have the "tipc_" prefix. Runtime behaviour is unchanged.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Make this rename so that it is consistent with the majority
of the other tipc structs and to assist in removing any
ambiguity with other similar names in other subsystems.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Make this rename so that it is consistent with the majority
of the other tipc structs and to assist in removing any
ambiguity with other similar names in other subsystems.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Make this rename so that it is consistent with the majority
of the other tipc structs and to assist in removing any
ambiguity with other similar names in other subsystems.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Make this rename so that it is consistent with the majority
of the other tipc structs and to assist in removing any
ambiguity with other similar names in other subsystems.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Migrates the buf_seqno() helper routine from broadcast link level to
unicast link level so that it can be used both types of TIPC links.
This is a cosmetic change only, and does not affect the operation of TIPC.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Adds checks to TIPC's broadcast link so that it ignores any
acknowledgement message containing a sequence number that does not
correspond to an unacknowledged message currently in the broadcast
link's transmit queue.
This change prevents the broadcast link from becoming stalled if a
newly booted node receives stale broadcast link acknowledgement
information from another node that has not yet fully synchronized
its end of the broadcast link to reflect the current state of the
new node's end.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Adds code to release any unsent broadcast messages in the broadcast link
transmit queue if TIPC loses contact with its only neighboring node.
Previously, a broadcast link that was in the congested state would hold
on to the unsent messages, even though the messages were now undeliverable.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The two broadcast link statistics fields that are used to derive the
average length of that link's transmit queue are now updated only after
a successful attempt to send a broadcast message, since there is no need
to update these values when an unsuccessful send attempt leaves the
queue unchanged.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Adds a check to detect when an attempt is made to send a message
via the broadcast link and no neighboring nodes are currently available
to receive it. Rather than wasting effort passing the message to the
broadcast link and broadcast bearer, who will only throw it away,
TIPC now frees the message immediately and reports success (i.e. the
message has been delivered to all available destinations).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Fixes oversight that allowed broadcast link node map to be updated without
first taking the broadcast link spinlock that protects the map. As part
of this fix the node map has been incorporated into the broadcast link
structure to make the need for such protection more evident.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Creates global variables to hold the broadcast link's pseudo-bearer and
pseudo-link structures, rather than allocating them dynamically. There
is only a single instance of each structure, and changing over to static
allocation allows elimination of code to handle the cases where dynamic
allocation was unsuccessful.
The memset in the teardown code may look like they aren't used, but
the same teardown code is run when there is a non-fatal error at
init-time, so that stale data isn't present when the user fixes the
cause of the soft error.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of an unnecessary check in the routine that updates the port id
of a node's name publications when the node is assigned a network address,
since the routine is only invoked if the new address is different from
the existing one.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies TIPC's module unloading logic to switch itself into "single
node" mode before starting to terminate networking support. This helps
to ensure that no operations that require TIPC to be in "networking"
mode can initiate once unloading starts.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Gets rid of two pointless operations that zero out the array used to
record information about TIPC's Ethernet bearers. There is no need to
initialize the array on start up since it is a global variable that is
already zero'd out, and there is no need to zero it out on exit because
the array is never referenced again.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Modifies Ethernet bearer disable logic to break the association between
the bearer and its device driver at the time the bearer is disabled,
rather than when the TIPC module is unloaded. This allows the array
entry used by the disabled bearer to be re-used if the same bearer (or
a different one) is subsequently enabled.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Change TIPC's shutdown code to deactivate generic networking support
before terminating Ethernet media support. The deactivation of generic
networking support causes all existing bearers to be destroyed, meaning
the Ethernet media termination routine no longer has to bother marking
them as unavailable.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Comment-only change to better explain why TIPC's configuration lock is
temporarily released while activating support for network interfaces,
and why the existing activation code doesn't require rework.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Adds a check to ensure that TIPC ignores an incoming neighbor discovery
message that specifies an invalid media address as its source. The check
ensures that the source address is a valid, non-broadcast address that
could legally be used by a neighboring link endpoint.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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>
Enhances TIPC's Ethernet media support to provide 3 new address conversion
routines, which allow TIPC to interpret an address that is in string form
and to convert an address to and from the 20 byte format used in TIPC's
neighbor discovery messages.
These routines are pre-requisites to a follow on commit that hides all
media-specific addressing details from TIPC's generic bearer code.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Enhances conversion of a media address to printable form so that an
unconvertable address will be displayed as a string of hex digits,
rather than not being displayed at all. (Also removes a pointless check
for the existence of the media-specific address conversion routine,
since the routine is not optional.)
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Simplifies error handling performed during media registration, since
TIPC no longer supports the dynamic addition of new media types that
are potentially error-prone. These simplifications include the following:
1) No longer check for premature registration of a new media type.
2) No longer check for negative link priority values (which was pointless
since such values are unsigned, and could cause a compiler warning).
3) No longer generate a warning describing the exact cause of any
registration failure (just warns that overall registration failed).
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>