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2016-09-13rxrpc: Add IPv6 supportDavid Howells
Add IPv6 support to AF_RXRPC. With this, AF_RXRPC sockets can be created: service = socket(AF_RXRPC, SOCK_DGRAM, PF_INET6); instead of: service = socket(AF_RXRPC, SOCK_DGRAM, PF_INET); The AFS filesystem doesn't support IPv6 at the moment, though, since that requires upgrades to some of the RPC calls. Note that a good portion of this patch is replacing "%pI4:%u" in print statements with "%pISpc" which is able to handle both protocols and print the port. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08rxrpc: Preallocate peers, conns and calls for incoming service requestsDavid Howells
Make it possible for the data_ready handler called from the UDP transport socket to completely instantiate an rxrpc_call structure and make it immediately live by preallocating all the memory it might need. The idea is to cut out the background thread usage as much as possible. [Note that the preallocated structs are not actually used in this patch - that will be done in a future patch.] If insufficient resources are available in the preallocation buffers, it will be possible to discard the DATA packet in the data_ready handler or schedule a BUSY packet without the need to schedule an attempt at allocation in a background thread. To this end: (1) Preallocate rxrpc_peer, rxrpc_connection and rxrpc_call structs to a maximum number each of the listen backlog size. The backlog size is limited to a maxmimum of 32. Only this many of each can be in the preallocation buffer. (2) For userspace sockets, the preallocation is charged initially by listen() and will be recharged by accepting or rejecting pending new incoming calls. (3) For kernel services {,re,dis}charging of the preallocation buffers is handled manually. Two notifier callbacks have to be provided before kernel_listen() is invoked: (a) An indication that a new call has been instantiated. This can be used to trigger background recharging. (b) An indication that a call is being discarded. This is used when the socket is being released. A function, rxrpc_kernel_charge_accept() is called by the kernel service to preallocate a single call. It should be passed the user ID to be used for that call and a callback to associate the rxrpc call with the kernel service's side of the ID. (4) Discard the preallocation when the socket is closed. (5) Temporarily bump the refcount on the call allocated in rxrpc_incoming_call() so that rxrpc_release_call() can ditch the preallocation ref on service calls unconditionally. This will no longer be necessary once the preallocation is used. Note that this does not yet control the number of active service calls on a client - that will come in a later patch. A future development would be to provide a setsockopt() call that allows a userspace server to manually charge the preallocation buffer. This would allow user call IDs to be provided in advance and the awkward manual accept stage to be bypassed. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07rxrpc: Calls shouldn't hold socket refsDavid Howells
rxrpc calls shouldn't hold refs on the sock struct. This was done so that the socket wouldn't go away whilst the call was in progress, such that the call could reach the socket's queues. However, we can mark the socket as requiring an RCU release and rely on the RCU read lock. To make this work, we do: (1) rxrpc_release_call() removes the call's call user ID. This is now only called from socket operations and not from the call processor: rxrpc_accept_call() / rxrpc_kernel_accept_call() rxrpc_reject_call() / rxrpc_kernel_reject_call() rxrpc_kernel_end_call() rxrpc_release_calls_on_socket() rxrpc_recvmsg() Though it is also called in the cleanup path of rxrpc_accept_incoming_call() before we assign a user ID. (2) Pass the socket pointer into rxrpc_release_call() rather than getting it from the call so that we can get rid of uninitialised calls. (3) Fix call processor queueing to pass a ref to the work queue and to release that ref at the end of the processor function (or to pass it back to the work queue if we have to requeue). (4) Skip out of the call processor function asap if the call is complete and don't requeue it if the call is complete. (5) Clean up the call immediately that the refcount reaches 0 rather than trying to defer it. Actual deallocation is deferred to RCU, however. (6) Don't hold socket refs for allocated calls. (7) Use the RCU read lock when queueing a message on a socket and treat the call's socket pointer according to RCU rules and check it for NULL. We also need to use the RCU read lock when viewing a call through procfs. (8) Transmit the final ACK/ABORT to a client call in rxrpc_release_call() if this hasn't been done yet so that we can then disconnect the call. Once the call is disconnected, it won't have any access to the connection struct and the UDP socket for the call work processor to be able to send the ACK. Terminal retransmission will be handled by the connection processor. (9) Release all calls immediately on the closing of a socket rather than trying to defer this. Incomplete calls will be aborted. The call refcount model is much simplified. Refs are held on the call by: (1) A socket's user ID tree. (2) A socket's incoming call secureq and acceptq. (3) A kernel service that has a call in progress. (4) A queued call work processor. We have to take care to put any call that we failed to queue. (5) sk_buffs on a socket's receive queue. A future patch will get rid of this. Whilst we're at it, we can do: (1) Get rid of the RXRPC_CALL_EV_RELEASE event. Release is now done entirely from the socket routines and never from the call's processor. (2) Get rid of the RXRPC_CALL_DEAD state. Calls now end in the RXRPC_CALL_COMPLETE state. (3) Get rid of the rxrpc_call::destroyer work item. Calls are now torn down when their refcount reaches 0 and then handed over to RCU for final cleanup. (4) Get rid of the rxrpc_call::deadspan timer. Calls are cleaned up immediately they're finished with and don't hang around. Post-completion retransmission is handled by the connection processor once the call is disconnected. (5) Get rid of the dead call expiry setting as there's no longer a timer to set. (6) rxrpc_destroy_all_calls() can just check that the call list is empty. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-30rxrpc: Calls should only have one terminal stateDavid Howells
Condense the terminal states of a call state machine to a single state, plus a separate completion type value. The value is then set, along with error and abort code values, only when the call is transitioned to the completion state. Helpers are provided to simplify this. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-24rxrpc: Dup the main conn list for the proc interfaceDavid Howells
The main connection list is used for two independent purposes: primarily it is used to find connections to reap and secondarily it is used to list connections in procfs. Split the procfs list out from the reap list. This allows us to stop using the reap list for client connections when they acquire a separate management strategy from service collections. The client connections will not be on a management single list, and sometimes won't be on a management list at all. This doesn't leave them floating, however, as they will also be on an rb-tree rooted on the socket so that the socket can find them to dispatch calls. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-24rxrpc: Make /proc/net/rxrpc_calls saferDavid Howells
Make /proc/net/rxrpc_calls safer by stashing a copy of the peer pointer in the rxrpc_call struct and checking in the show routine that the peer pointer, the socket pointer and the local pointer obtained from the socket pointer aren't NULL before we use them. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-23rxrpc: Calculate serial skew on packet receptionDavid Howells
Calculate the serial number skew in the data_ready handler when a packet has been received and a connection looked up. The skew is cached in the sk_buff's priority field. The connection highest received serial number is updated at this time also. This can be done without locks or atomic instructions because, at this point, the code is serialised by the socket. This generates more accurate skew data because if the packet is offloaded to a work queue before this is determined, more packets may come in, bumping the highest serial number and thereby increasing the apparent skew. This also removes some unnecessary atomic ops. Signed-off-by: David Howells <dhowells@redhat.com>
2016-08-23rxrpc: Tidy up the rxrpc_call struct a bitDavid Howells
Do a little tidying of the rxrpc_call struct: (1) in_clientflag is no longer compared against the value that's in the packet, so keeping it in this form isn't necessary. Use a flag in flags instead and provide a pair of wrapper functions. (2) We don't read the epoch value, so that can go. (3) Move what remains of the data that were used for hashing up in the struct to be with the channel number. (4) Get rid of the local pointer. We can get at this via the socket struct and we only use this in the procfs viewer. Signed-off-by: David Howells <dhowells@redhat.com>
2016-07-06rxrpc: Call channels should have separate call number spacesDavid Howells
Each channel on a connection has a separate, independent number space from which to allocate callNumber values. It is entirely possible, for example, to have a connection with four active calls, each with call number 1. Note that the callNumber values for any particular channel don't have to start at 1, but they are supposed to increment monotonically for that channel from a client's perspective and may not be reused once the call number is transmitted (until the epoch cycles all the way back round). Currently, however, call numbers are allocated on a per-connection basis and, further, are held in an rb-tree. The rb-tree is redundant as the four channel pointers in the rxrpc_connection struct are entirely capable of pointing to all the calls currently in progress on a connection. To this end, make the following changes: (1) Handle call number allocation independently per channel. (2) Get rid of the conn->calls rb-tree. This is overkill as a connection may have a maximum of four calls in progress at any one time. Use the pointers in the channels[] array instead, indexed by the channel number from the packet. (3) For each channel, save the result of the last call that was in progress on that channel in conn->channels[] so that the final ACK or ABORT packet can be replayed if necessary. Any call earlier than that is just ignored. If we've seen the next call number in a packet, the last one is most definitely defunct. (4) When generating a RESPONSE packet for a connection, the call number counter for each channel must be included in it. (5) When parsing a RESPONSE packet for a connection, the call number counters contained therein should be used to set the minimum expected call numbers on each channel. To do in future commits: (1) Replay terminal packets based on the last call stored in conn->channels[]. (2) Connections should be retired before the callNumber space on any channel runs out. (3) A server is expected to disregard or reject any new incoming call that has a call number less than the current call number counter. The call number counter for that channel must be advanced to the new call number. Note that the server cannot just require that the next call that it sees on a channel be exactly the call number counter + 1 because then there's a scenario that could cause a problem: The client transmits a packet to initiate a connection, the network goes out, the server sends an ACK (which gets lost), the client sends an ABORT (which also gets lost); the network then reconnects, the client then reuses the call number for the next call (it doesn't know the server already saw the call number), but the server thinks it already has the first packet of this call (it doesn't know that the client doesn't know that it saw the call number the first time). Signed-off-by: David Howells <dhowells@redhat.com>
2016-07-06rxrpc: Turn connection #defines into enums and put outside struct defDavid Howells
Turn the connection event and state #define lists into enums and move outside of the struct definition. Whilst we're at it, change _SERVER to _SERVICE in those identifiers and add EV_ into the event name to distinguish them from flags and states. Also add a symbol indicating the number of states and use that in the state text array. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-22rxrpc: Calls displayed in /proc may in future lack a connectionDavid Howells
Allocated rxrpc calls displayed in /proc/net/rxrpc_calls may in future be on the proc list before they're connected or after they've been disconnected - in which case they may not have a pointer to a connection struct that can be used to get data from there. Deal with this by using stuff from the call struct in preference where possible and printing "no_connection" rather than a peer address if no connection is assigned. This change also has the added bonus that the service ID is now taken from the call rather the connection which will allow per-call service upgrades to be shown - something required for AuriStor server compatibility. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-22rxrpc: Replace conn->trans->{local,peer} with conn->params.{local,peer}David Howells
Replace accesses of conn->trans->{local,peer} with conn->params.{local,peer} thus making it easier for a future commit to remove the rxrpc_transport struct. This also reduces the number of memory accesses involved. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-22rxrpc: Use structs to hold connection params and protocol infoDavid Howells
Define and use a structure to hold connection parameters. This makes it easier to pass multiple connection parameters around. Define and use a structure to hold protocol information used to hash a connection for lookup on incoming packet. Most of these fields will be disposed of eventually, including the duplicate local pointer. Whilst we're at it rename "proto" to "family" when referring to a protocol family. Signed-off-by: David Howells <dhowells@redhat.com>
2016-06-13rxrpc: Rename files matching ar-*.c to git rid of the "ar-" prefixDavid Howells
Rename files matching net/rxrpc/ar-*.c to get rid of the "ar-" prefix. This will aid splitting those files by making easier to come up with new names. Note that the not all files are simply renamed from ar-X.c to X.c. The following exceptions are made: (*) ar-call.c -> call_object.c ar-ack.c -> call_event.c call_object.c is going to contain the core of the call object handling. Call event handling is all going to be in call_event.c. (*) ar-accept.c -> call_accept.c Incoming call handling is going to be here. (*) ar-connection.c -> conn_object.c ar-connevent.c -> conn_event.c The former file is going to have the basic connection object handling, but there will likely be some differentiation between client connections and service connections in additional files later. The latter file will have all the connection-level event handling. (*) ar-local.c -> local_object.c This will have the local endpoint object handling code. The local endpoint event handling code will later be split out into local_event.c. (*) ar-peer.c -> peer_object.c This will have the peer endpoint object handling code. Peer event handling code will be placed in peer_event.c (for the moment, there is none). (*) ar-error.c -> peer_event.c This will become the peer event handling code, though for the moment it's actually driven from the local endpoint's perspective. Note that I haven't renamed ar-transport.c to transport_object.c as the intention is to delete it when the rxrpc_transport struct is excised. The only file that actually has its contents changed is net/rxrpc/Makefile. net/rxrpc/ar-internal.h will need its section marker comments updating, but I'll do that in a separate patch to make it easier for git to follow the history across the rename. I may also want to rename ar-internal.h at some point - but that would mean updating all the #includes and I'd rather do that in a separate step. Signed-off-by: David Howells <dhowells@redhat.com.
2007-04-26[AF_RXRPC]: Delete the old RxRPC code.David Howells
Delete the old RxRPC code as it's now no longer used. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-12[PATCH] mark struct file_operations const 8Arjan van de Ven
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-01-17[NET]: "signed long" -> "long"Kris Katterjohn
Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!