BMC/Intel-BMC/linux.git/net/tipc/discover.c, branch dev-4.17

tipc: tipc_disc_addr_trial_msg() can be static

2018-03-26T01:21:43+00:00

Fixes: 25b0b9c4e835 ("tipc: handle collisions of 32-bit node address hash values") Signed-off-by: Fengguang Wu Acked-by: Jon Maloy jon.maloy@ericsson.com Signed-off-by: David S. Miller

tipc: handle collisions of 32-bit node address hash values

2018-03-23T17:12:18+00:00

When a 32-bit node address is generated from a 128-bit identifier, there is a risk of collisions which must be discovered and handled. We do this as follows: - We don't apply the generated address immediately to the node, but do instead initiate a 1 sec trial period to allow other cluster members to discover and handle such collisions. - During the trial period the node periodically sends out a new type of message, DSC_TRIAL_MSG, using broadcast or emulated broadcast, to all the other nodes in the cluster. - When a node is receiving such a message, it must check that the presented 32-bit identifier either is unused, or was used by the very same peer in a previous session. In both cases it accepts the request by not responding to it. - If it finds that the same node has been up before using a different address, it responds with a DSC_TRIAL_FAIL_MSG containing that address. - If it finds that the address has already been taken by some other node, it generates a new, unused address and returns it to the requester. - During the trial period the requesting node must always be prepared to accept a failure message, i.e., a message where a peer suggests a different (or equal) address to the one tried. In those cases it must apply the suggested value as trial address and restart the trial period. This algorithm ensures that in the vast majority of cases a node will have the same address before and after a reboot. If a legacy user configures the address explicitly, there will be no trial period and messages, so this protocol addition is completely backwards compatible. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: add 128-bit node identifier

2018-03-23T17:12:18+00:00

We add a 128-bit node identity, as an alternative to the currently used 32-bit node address. For the sake of compatibility and to minimize message header changes we retain the existing 32-bit address field. When not set explicitly by the user, this field will be filled with a hash value generated from the much longer node identity, and be used as a shorthand value for the latter. We permit either the address or the identity to be set by configuration, but not both, so when the address value is set by a legacy user the corresponding 128-bit node identity is generated based on the that value. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: remove direct accesses to own_addr field in struct tipc_net

2018-03-23T17:12:18+00:00

As a preparation to changing the addressing structure of TIPC we replace all direct accesses to the tipc_net::own_addr field with the function dedicated for this, tipc_own_addr(). There are no changes to program logics in this commit. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: allow closest-first lookup algorithm when legacy address is configured

2018-03-23T17:12:18+00:00

The removal of an internal structure of the node address has an unwanted side effect. - Currently, if a user is sending an anycast message with destination domain 0, the tipc_namebl_translate() function will use the 'closest- first' algorithm to first look for a node local destination, and only when no such is found, will it resort to the cluster global 'round- robin' lookup algorithm. - Current users can get around this, and enforce unconditional use of global round-robin by indicating a destination as Z.0.0 or Z.C.0. - This option disappears when we make the node address flat, since the lookup algorithm has no way of recognizing this case. So, as long as there are node local destinations, the algorithm will always select one of those, and there is nothing the sender can do to change this. We solve this by eliminating the 'closest-first' option, which was never a good idea anyway, for non-legacy users, but only for those. To distinguish between legacy users and non-legacy users we introduce a new flag 'legacy_addr_format' in struct tipc_core, to be set when the user configures a legacy-style Z.C.N node address. Hence, when a legacy user indicates a zero lookup domain 'closest-first' is selected, and in all other cases we use 'round-robin'. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: remove restrictions on node address values

2018-03-23T17:12:18+00:00

Nominally, TIPC organizes network nodes into a three-level network hierarchy consisting of the levels 'zone', 'cluster' and 'node'. This hierarchy is reflected in the node address format, - it is sub-divided into an 8-bit zone id, and 12 bit cluster id, and a 12-bit node id. However, the 'zone' and 'cluster' levels have in reality never been fully implemented,and never will be. The result of this has been that the first 20 bits the node identity structure have been wasted, and the usable node identity range within a cluster has been limited to 12 bits. This is starting to become a problem. In the following commits, we will need to be able to connect between nodes which are using the whole 32-bit value space of the node address. We therefore remove the restrictions on which values can be assigned to node identity, -it is from now on only a 32-bit integer with no assumed internal structure. Isolation between clusters is now achieved only by setting different values for the 'network id' field used during neighbor discovery, in practice leading to the latter becoming the new cluster identity. The rules for accepting discovery requests/responses from neighboring nodes now become: - If the user is using legacy address format on both peers, reception of discovery messages is subject to the legacy lookup domain check in addition to the cluster id check. - Otherwise, the discovery request/response is always accepted, provided both peers have the same network id. This secures backwards compatibility for users who have been using zone or cluster identities as cluster separators, instead of the intended 'network id'. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: some cleanups in the file discover.c

2018-03-23T17:12:17+00:00

To facilitate the coming changes in the neighbor discovery functionality we make some renaming and refactoring of that code. The functional changes in this commit are trivial, e.g., that we move the message sending call in tipc_disc_timeout() outside the spinlock protected region. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

net: tipc: Convert timers to use timer_setup()

2017-11-01T03:38:45+00:00

In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly. Cc: Jon Maloy Cc: Ying Xue Cc: "David S. Miller" Cc: netdev@vger.kernel.org Cc: tipc-discussion@lists.sourceforge.net Signed-off-by: Kees Cook Signed-off-by: David S. Miller

tipc: allocate user memory with GFP_KERNEL flag

2017-01-16T18:31:53+00:00

Until now, we allocate memory always with GFP_ATOMIC flag. When the system is under memory pressure and a user tries to send, the send fails due to low memory. However, the user application can wait for free memory if we allocate it using GFP_KERNEL flag. In this commit, we use allocate memory with GFP_KERNEL for all user allocation. Reported-by: Rune Torgersen Acked-by: Jon Maloy Signed-off-by: Parthasarathy Bhuvaragan Signed-off-by: David S. Miller

tipc: honor msg2addr return value

2016-06-29T09:17:37+00:00

The UDP msg2addr function tipc_udp_msg2addr() can return -EINVAL which prior to this patch was unhanded in the caller. Signed-off-by: Richard Alpe Acked-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: David S. Miller