This project is mirrored from https://git.kernel.org/pub/scm/linux/kernel/git/wagi/linux-cip-rt.git. The repository failed to update .
Repository mirroring has been paused due to too many failed attempts, and can be resumed by a project maintainer.
Last successful update .
  1. 19 May, 2011 1 commit
  2. 31 Oct, 2008 1 commit
  3. 04 May, 2007 1 commit
    • David Howells's avatar
      [AF_RXRPC]: Sort out MTU handling. · 224711df
      David Howells authored
      Sort out the MTU determination and handling in AF_RXRPC:
      
       (1) If it's present, parse the additional information supplied by the peer at
           the end of the ACK packet (struct ackinfo) to determine the MTU sizes
           that peer is willing to support.
      
       (2) Initialise the MTU size to that peer from the kernel's routing records.
      
       (3) Send ACKs rather than ACKALLs as the former carry the additional info,
           and the latter do not.
      
       (4) Declare the interface MTU size in outgoing ACKs as a maximum amount of
           data that can be stuffed into an RxRPC packet without it having to be
           fragmented to come in this computer's NIC.
      
       (5) If sendmsg() is given MSG_MORE then it should allocate an skb of the
           maximum size rather than one just big enough for the data it's got left
           to process on the theory that there is more data to come that it can
           append to that packet.
      
           This means, for example, that if AFS does a large StoreData op, all the
           packets barring the last will be filled to the maximum unfragmented size.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      224711df
  4. 26 Apr, 2007 2 commits
    • David Howells's avatar
      [AF_RXRPC]: Add an interface to the AF_RXRPC module for the AFS filesystem to use · 651350d1
      David Howells authored
      Add an interface to the AF_RXRPC module so that the AFS filesystem module can
      more easily make use of the services available.  AFS still opens a socket but
      then uses the action functions in lieu of sendmsg() and registers an intercept
      functions to grab messages before they're queued on the socket Rx queue.
      
      This permits AFS (or whatever) to:
      
       (1) Avoid the overhead of using the recvmsg() call.
      
       (2) Use different keys directly on individual client calls on one socket
           rather than having to open a whole slew of sockets, one for each key it
           might want to use.
      
       (3) Avoid calling request_key() at the point of issue of a call or opening of
           a socket.  This is done instead by AFS at the point of open(), unlink() or
           other VFS operation and the key handed through.
      
       (4) Request the use of something other than GFP_KERNEL to allocate memory.
      
      Furthermore:
      
       (*) The socket buffer markings used by RxRPC are made available for AFS so
           that it can interpret the cooked RxRPC messages itself.
      
       (*) rxgen (un)marshalling abort codes are made available.
      
      
      The following documentation for the kernel interface is added to
      Documentation/networking/rxrpc.txt:
      
      =========================
      AF_RXRPC KERNEL INTERFACE
      =========================
      
      The AF_RXRPC module also provides an interface for use by in-kernel utilities
      such as the AFS filesystem.  This permits such a utility to:
      
       (1) Use different keys directly on individual client calls on one socket
           rather than having to open a whole slew of sockets, one for each key it
           might want to use.
      
       (2) Avoid having RxRPC call request_key() at the point of issue of a call or
           opening of a socket.  Instead the utility is responsible for requesting a
           key at the appropriate point.  AFS, for instance, would do this during VFS
           operations such as open() or unlink().  The key is then handed through
           when the call is initiated.
      
       (3) Request the use of something other than GFP_KERNEL to allocate memory.
      
       (4) Avoid the overhead of using the recvmsg() call.  RxRPC messages can be
           intercepted before they get put into the socket Rx queue and the socket
           buffers manipulated directly.
      
      To use the RxRPC facility, a kernel utility must still open an AF_RXRPC socket,
      bind an addess as appropriate and listen if it's to be a server socket, but
      then it passes this to the kernel interface functions.
      
      The kernel interface functions are as follows:
      
       (*) Begin a new client call.
      
      	struct rxrpc_call *
      	rxrpc_kernel_begin_call(struct socket *sock,
      				struct sockaddr_rxrpc *srx,
      				struct key *key,
      				unsigned long user_call_ID,
      				gfp_t gfp);
      
           This allocates the infrastructure to make a new RxRPC call and assigns
           call and connection numbers.  The call will be made on the UDP port that
           the socket is bound to.  The call will go to the destination address of a
           connected client socket unless an alternative is supplied (srx is
           non-NULL).
      
           If a key is supplied then this will be used to secure the call instead of
           the key bound to the socket with the RXRPC_SECURITY_KEY sockopt.  Calls
           secured in this way will still share connections if at all possible.
      
           The user_call_ID is equivalent to that supplied to sendmsg() in the
           control data buffer.  It is entirely feasible to use this to point to a
           kernel data structure.
      
           If this function is successful, an opaque reference to the RxRPC call is
           returned.  The caller now holds a reference on this and it must be
           properly ended.
      
       (*) End a client call.
      
      	void rxrpc_kernel_end_call(struct rxrpc_call *call);
      
           This is used to end a previously begun call.  The user_call_ID is expunged
           from AF_RXRPC's knowledge and will not be seen again in association with
           the specified call.
      
       (*) Send data through a call.
      
      	int rxrpc_kernel_send_data(struct rxrpc_call *call, struct msghdr *msg,
      				   size_t len);
      
           This is used to supply either the request part of a client call or the
           reply part of a server call.  msg.msg_iovlen and msg.msg_iov specify the
           data buffers to be used.  msg_iov may not be NULL and must point
           exclusively to in-kernel virtual addresses.  msg.msg_flags may be given
           MSG_MORE if there will be subsequent data sends for this call.
      
           The msg must not specify a destination address, control data or any flags
           other than MSG_MORE.  len is the total amount of data to transmit.
      
       (*) Abort a call.
      
      	void rxrpc_kernel_abort_call(struct rxrpc_call *call, u32 abort_code);
      
           This is used to abort a call if it's still in an abortable state.  The
           abort code specified will be placed in the ABORT message sent.
      
       (*) Intercept received RxRPC messages.
      
      	typedef void (*rxrpc_interceptor_t)(struct sock *sk,
      					    unsigned long user_call_ID,
      					    struct sk_buff *skb);
      
      	void
      	rxrpc_kernel_intercept_rx_messages(struct socket *sock,
      					   rxrpc_interceptor_t interceptor);
      
           This installs an interceptor function on the specified AF_RXRPC socket.
           All messages that would otherwise wind up in the socket's Rx queue are
           then diverted to this function.  Note that care must be taken to process
           the messages in the right order to maintain DATA message sequentiality.
      
           The interceptor function itself is provided with the address of the socket
           and handling the incoming message, the ID assigned by the kernel utility
           to the call and the socket buffer containing the message.
      
           The skb->mark field indicates the type of message:
      
      	MARK				MEANING
      	===============================	=======================================
      	RXRPC_SKB_MARK_DATA		Data message
      	RXRPC_SKB_MARK_FINAL_ACK	Final ACK received for an incoming call
      	RXRPC_SKB_MARK_BUSY		Client call rejected as server busy
      	RXRPC_SKB_MARK_REMOTE_ABORT	Call aborted by peer
      	RXRPC_SKB_MARK_NET_ERROR	Network error detected
      	RXRPC_SKB_MARK_LOCAL_ERROR	Local error encountered
      	RXRPC_SKB_MARK_NEW_CALL		New incoming call awaiting acceptance
      
           The remote abort message can be probed with rxrpc_kernel_get_abort_code().
           The two error messages can be probed with rxrpc_kernel_get_error_number().
           A new call can be accepted with rxrpc_kernel_accept_call().
      
           Data messages can have their contents extracted with the usual bunch of
           socket buffer manipulation functions.  A data message can be determined to
           be the last one in a sequence with rxrpc_kernel_is_data_last().  When a
           data message has been used up, rxrpc_kernel_data_delivered() should be
           called on it..
      
           Non-data messages should be handled to rxrpc_kernel_free_skb() to dispose
           of.  It is possible to get extra refs on all types of message for later
           freeing, but this may pin the state of a call until the message is finally
           freed.
      
       (*) Accept an incoming call.
      
      	struct rxrpc_call *
      	rxrpc_kernel_accept_call(struct socket *sock,
      				 unsigned long user_call_ID);
      
           This is used to accept an incoming call and to assign it a call ID.  This
           function is similar to rxrpc_kernel_begin_call() and calls accepted must
           be ended in the same way.
      
           If this function is successful, an opaque reference to the RxRPC call is
           returned.  The caller now holds a reference on this and it must be
           properly ended.
      
       (*) Reject an incoming call.
      
      	int rxrpc_kernel_reject_call(struct socket *sock);
      
           This is used to reject the first incoming call on the socket's queue with
           a BUSY message.  -ENODATA is returned if there were no incoming calls.
           Other errors may be returned if the call had been aborted (-ECONNABORTED)
           or had timed out (-ETIME).
      
       (*) Record the delivery of a data message and free it.
      
      	void rxrpc_kernel_data_delivered(struct sk_buff *skb);
      
           This is used to record a data message as having been delivered and to
           update the ACK state for the call.  The socket buffer will be freed.
      
       (*) Free a message.
      
      	void rxrpc_kernel_free_skb(struct sk_buff *skb);
      
           This is used to free a non-DATA socket buffer intercepted from an AF_RXRPC
           socket.
      
       (*) Determine if a data message is the last one on a call.
      
      	bool rxrpc_kernel_is_data_last(struct sk_buff *skb);
      
           This is used to determine if a socket buffer holds the last data message
           to be received for a call (true will be returned if it does, false
           if not).
      
           The data message will be part of the reply on a client call and the
           request on an incoming call.  In the latter case there will be more
           messages, but in the former case there will not.
      
       (*) Get the abort code from an abort message.
      
      	u32 rxrpc_kernel_get_abort_code(struct sk_buff *skb);
      
           This is used to extract the abort code from a remote abort message.
      
       (*) Get the error number from a local or network error message.
      
      	int rxrpc_kernel_get_error_number(struct sk_buff *skb);
      
           This is used to extract the error number from a message indicating either
           a local error occurred or a network error occurred.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      651350d1
    • David Howells's avatar
      [AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both · 17926a79
      David Howells authored
      Provide AF_RXRPC sockets that can be used to talk to AFS servers, or serve
      answers to AFS clients.  KerberosIV security is fully supported.  The patches
      and some example test programs can be found in:
      
      	http://people.redhat.com/~dhowells/rxrpc/
      
      This will eventually replace the old implementation of kernel-only RxRPC
      currently resident in net/rxrpc/.
      Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      17926a79