Lustre RPCs
-----------
[[lustre-rpcs]]

The Lustre protocol consists of a collection of remote procedure calls
(RPCs) collectively known as PtlRPCs. Each Lustre RPC is an operation
that consists of a pair of messages, a request and its reply.  The
'pb_type' field is set to PTLRPC_MSG_REQUEST for requests initiating
the operation, and normally PTLRPC_MSG_REPLY for replies unless the
message encountered a fatal error before it could be processed, in
which case it will contain PTLRPC_MSG_ERR.

The type of operation requested is denoted by the 'pb_opc' op-code
field of the RPC request. Note that as a general matter, the receipt
by a client of the reply message only assures the client that the
server has initiated the action, if any, but does not guarantee that
any modification has been committed to persistent storage. See the
discussion in <<transno>> and <<recovery>> for how the client is given
confirmation that a request has been completed.

include::ost_setattr.txt[]

include::ost_connect.txt[]

include::ost_disconnect.txt[]

include::ost_punch.txt[]

include::ost_statfs.txt[]

include::mds_getattr.txt[]

include::mds_reint.txt[]

include::mds_connect.txt[]

include::mds_disconnect.txt[]

include::mds_getstatus.txt[]

include::mds_statfs.txt[]

include::mds_getxattr.txt[]

include::ldlm_enqueue.txt[]

include::ldlm_cancel.txt[]

include::ldlm_bl_callback.txt[]

include::ldlm_cp_callback.txt[]

include::ldlm_gl_callback.txt[]

include::mgs_connect.txt[]

include::mgs_disconnect.txt[]

include::mgs_config_read.txt[]

include::llog_origin_handle_create.txt[]

include::llog_origin_handle_next_block.txt[]

include::llog_origin_handle_read_header.txt[]

include::struct_lustre_msg.txt[]