1. 31 3月, 2018 1 次提交
  2. 05 6月, 2017 2 次提交
    • D
      rxrpc: Permit multiple service binding · 28036f44
      David Howells 提交于
      Permit bind() to be called on an AF_RXRPC socket more than once (currently
      maximum twice) to bind multiple listening services to it.  There are some
      restrictions:
      
       (1) All bind() calls involved must have a non-zero service ID.
      
       (2) The service IDs must all be different.
      
       (3) The rest of the address (notably the transport part) must be the same
           in all (a single UDP socket is shared).
      
       (4) This must be done before listen() or sendmsg() is called.
      
      This allows someone to connect to the service socket with different service
      IDs and lays the foundation for service upgrading.
      
      The service ID used by an incoming call can be extracted from the msg_name
      returned by recvmsg().
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      28036f44
    • D
      rxrpc: Separate the connection's protocol service ID from the lookup ID · 68d6d1ae
      David Howells 提交于
      Keep the rxrpc_connection struct's idea of the service ID that is exposed
      in the protocol separate from the service ID that's used as a lookup key.
      
      This allows the protocol service ID on a client connection to get upgraded
      without making the connection unfindable for other client calls that also
      would like to use the upgraded connection.
      
      The connection's actual service ID is then returned through recvmsg() by
      way of msg_name.
      
      Whilst we're at it, we get rid of the last_service_id field from each
      channel.  The service ID is per-connection, not per-call and an entire
      connection is upgraded in one go.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      68d6d1ae
  3. 30 9月, 2016 1 次提交
    • D
      rxrpc: Reduce the rxrpc_local::services list to a pointer · 1e9e5c95
      David Howells 提交于
      Reduce the rxrpc_local::services list to just a pointer as we don't permit
      multiple service endpoints to bind to a single transport endpoints (this is
      excluded by rxrpc_lookup_local()).
      
      The reason we don't allow this is that if you send a request to an AFS
      filesystem service, it will try to talk back to your cache manager on the
      port you sent from (this is how file change notifications are handled).  To
      prevent someone from stealing your CM callbacks, we don't let AF_RXRPC
      sockets share a UDP socket if at least one of them has a service bound.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      1e9e5c95
  4. 08 9月, 2016 2 次提交
    • D
      rxrpc: Rewrite the data and ack handling code · 248f219c
      David Howells 提交于
      Rewrite the data and ack handling code such that:
      
       (1) Parsing of received ACK and ABORT packets and the distribution and the
           filing of DATA packets happens entirely within the data_ready context
           called from the UDP socket.  This allows us to process and discard ACK
           and ABORT packets much more quickly (they're no longer stashed on a
           queue for a background thread to process).
      
       (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim().  We instead
           keep track of the offset and length of the content of each packet in
           the sk_buff metadata.  This means we don't do any allocation in the
           receive path.
      
       (3) Jumbo DATA packet parsing is now done in data_ready context.  Rather
           than cloning the packet once for each subpacket and pulling/trimming
           it, we file the packet multiple times with an annotation for each
           indicating which subpacket is there.  From that we can directly
           calculate the offset and length.
      
       (4) A call's receive queue can be accessed without taking locks (memory
           barriers do have to be used, though).
      
       (5) Incoming calls are set up from preallocated resources and immediately
           made live.  They can than have packets queued upon them and ACKs
           generated.  If insufficient resources exist, DATA packet #1 is given a
           BUSY reply and other DATA packets are discarded).
      
       (6) sk_buffs no longer take a ref on their parent call.
      
      To make this work, the following changes are made:
      
       (1) Each call's receive buffer is now a circular buffer of sk_buff
           pointers (rxtx_buffer) rather than a number of sk_buff_heads spread
           between the call and the socket.  This permits each sk_buff to be in
           the buffer multiple times.  The receive buffer is reused for the
           transmit buffer.
      
       (2) A circular buffer of annotations (rxtx_annotations) is kept parallel
           to the data buffer.  Transmission phase annotations indicate whether a
           buffered packet has been ACK'd or not and whether it needs
           retransmission.
      
           Receive phase annotations indicate whether a slot holds a whole packet
           or a jumbo subpacket and, if the latter, which subpacket.  They also
           note whether the packet has been decrypted in place.
      
       (3) DATA packet window tracking is much simplified.  Each phase has just
           two numbers representing the window (rx_hard_ack/rx_top and
           tx_hard_ack/tx_top).
      
           The hard_ack number is the sequence number before base of the window,
           representing the last packet the other side says it has consumed.
           hard_ack starts from 0 and the first packet is sequence number 1.
      
           The top number is the sequence number of the highest-numbered packet
           residing in the buffer.  Packets between hard_ack+1 and top are
           soft-ACK'd to indicate they've been received, but not yet consumed.
      
           Four macros, before(), before_eq(), after() and after_eq() are added
           to compare sequence numbers within the window.  This allows for the
           top of the window to wrap when the hard-ack sequence number gets close
           to the limit.
      
           Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also
           to indicate when rx_top and tx_top point at the packets with the
           LAST_PACKET bit set, indicating the end of the phase.
      
       (4) Calls are queued on the socket 'receive queue' rather than packets.
           This means that we don't need have to invent dummy packets to queue to
           indicate abnormal/terminal states and we don't have to keep metadata
           packets (such as ABORTs) around
      
       (5) The offset and length of a (sub)packet's content are now passed to
           the verify_packet security op.  This is currently expected to decrypt
           the packet in place and validate it.
      
           However, there's now nowhere to store the revised offset and length of
           the actual data within the decrypted blob (there may be a header and
           padding to skip) because an sk_buff may represent multiple packets, so
           a locate_data security op is added to retrieve these details from the
           sk_buff content when needed.
      
       (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is
           individually secured and needs to be individually decrypted.  The code
           to do this is broken out into rxrpc_recvmsg_data() and shared with the
           kernel API.  It now iterates over the call's receive buffer rather
           than walking the socket receive queue.
      
      Additional changes:
      
       (1) The timers are condensed to a single timer that is set for the soonest
           of three timeouts (delayed ACK generation, DATA retransmission and
           call lifespan).
      
       (2) Transmission of ACK and ABORT packets is effected immediately from
           process-context socket ops/kernel API calls that cause them instead of
           them being punted off to a background work item.  The data_ready
           handler still has to defer to the background, though.
      
       (3) A shutdown op is added to the AF_RXRPC socket so that the AFS
           filesystem can shut down the socket and flush its own work items
           before closing the socket to deal with any in-progress service calls.
      
      Future additional changes that will need to be considered:
      
       (1) Make sure that a call doesn't hog the front of the queue by receiving
           data from the network as fast as userspace is consuming it to the
           exclusion of other calls.
      
       (2) Transmit delayed ACKs from within recvmsg() when we've consumed
           sufficiently more packets to avoid the background work item needing to
           run.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      248f219c
    • D
      rxrpc: Convert rxrpc_local::services to an hlist · de8d6c74
      David Howells 提交于
      Convert the rxrpc_local::services list to an hlist so that it can be
      accessed under RCU conditions more readily.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      de8d6c74
  5. 22 6月, 2016 2 次提交
  6. 13 6月, 2016 1 次提交
    • D
      rxrpc: Rename files matching ar-*.c to git rid of the "ar-" prefix · 8c3e34a4
      David Howells 提交于
      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.
      8c3e34a4
  7. 12 4月, 2016 2 次提交
  8. 04 3月, 2016 2 次提交
    • D
      rxrpc: Adjust some whitespace and comments · b4f1342f
      David Howells 提交于
      Remove some excess whitespace, insert some missing spaces and adjust a
      couple of comments.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      b4f1342f
    • D
      rxrpc: Keep the skb private record of the Rx header in host byte order · 0d12f8a4
      David Howells 提交于
      Currently, a copy of the Rx packet header is copied into the the sk_buff
      private data so that we can advance the pointer into the buffer,
      potentially discarding the original.  At the moment, this copy is held in
      network byte order, but this means we're doing a lot of unnecessary
      translations.
      
      The reasons it was done this way are that we need the values in network
      byte order occasionally and we can use the copy, slightly modified, as part
      of an iov array when sending an ack or an abort packet.
      
      However, it seems more reasonable on review that it would be better kept in
      host byte order and that we make up a new header when we want to send
      another packet.
      
      To this end, rename the original header struct to rxrpc_wire_header (with
      BE fields) and institute a variant called rxrpc_host_header that has host
      order fields.  Change the struct in the sk_buff private data into an
      rxrpc_host_header and translate the values when filling it in.
      
      This further allows us to keep values kept in various structures in host
      byte order rather than network byte order and allows removal of some fields
      that are byteswapped duplicates.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      0d12f8a4
  9. 21 10月, 2015 1 次提交
    • D
      KEYS: Merge the type-specific data with the payload data · 146aa8b1
      David Howells 提交于
      Merge the type-specific data with the payload data into one four-word chunk
      as it seems pointless to keep them separate.
      
      Use user_key_payload() for accessing the payloads of overloaded
      user-defined keys.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      cc: linux-cifs@vger.kernel.org
      cc: ecryptfs@vger.kernel.org
      cc: linux-ext4@vger.kernel.org
      cc: linux-f2fs-devel@lists.sourceforge.net
      cc: linux-nfs@vger.kernel.org
      cc: ceph-devel@vger.kernel.org
      cc: linux-ima-devel@lists.sourceforge.net
      146aa8b1
  10. 15 9月, 2009 1 次提交
  11. 11 12月, 2008 1 次提交
  12. 27 4月, 2007 1 次提交