ldlm_cp_callback.txt

   1 RPC 105: LDLM_CP_CALLBACK
   2 ~~~~~~~~~~~~~~~~~~~~~~~~~
   3 [[ldlm-cp-callback-rpc]]
   4
   5 An RPC that notifies an entity that a requested lock is now available.
   6
   7 .LDLM_CP_CALLBACK Request Packet Structure
   8 image::ldlm-cp-callback-request.png["LDLM_CP_CALLBACK Request Packet Structure",height=50]
   9
  10 //////////////////////////////////////////////////////////////////////
  11 The ldlm-cp-callback-request.png diagram resembles this text
  12 art:
  13
  14        LDLM_CP_CALLBACK:
  15       --request-------------------------------
  16       | ptlrpc_body | ldlm_request | ost_lvb |
  17       ----------------------------------------
  18 //////////////////////////////////////////////////////////////////////
  19
  20 The request RPC identifies the relevant resource that already had a
  21 request pending. It notifies the original requester that it now has
  22 the stated lock, along with attribute information the about the
  23 resource.
  24
  25 'ptlrpc_body'::
  26 RPC descriptor <<struct-ptlrpc-body>>.
  27
  28 'ldlm_request'::
  29 Description of the lock being requested. Which resource is the target,
  30 what lock is current, and what lock desired. <<struct-ldlm-request>>
  31
  32 'ost_lvb'::
  33 Attribute data associated with a resource on an OST. <<struct-ost-lvb>>
  34
  35 .LDLM_CP_CALLBACK Reply Packet Structure
  36 image::ldlm-cp-callback-reply.png["LDLM_CP_CALLBACK Reply Packet Structure",height=50]
  37
  38 //////////////////////////////////////////////////////////////////////
  39 The ldlm-cp-callback-reply.png diagram resembles this text
  40 art:
  41
  42        LDLM_CP_CALLBACK:
  43       --reply--------
  44       | ptlrpc_body |
  45       ---------------
  46 //////////////////////////////////////////////////////////////////////
  47
  48 The reply is just an acknowledgment of receipt, and doesn't
  49 carry any further information about the lock or the resource.
  50
  51 'ptlrpc_body'::
  52 RPC descriptor <<struct-ptlrpc-body>>.
  53