ptlrpc.txt is a beginning effort to document the precise structure of
PtlRPC messages including all fields and their meanings. For now it
has some general discussion and details about the message header and
the ptlrpc_body_v3 structures. It will eventually include all the
structures. 

request_message_pairs.txt lists the 94 named message pairs and the
names of the message format for each of the two messages in the
pair. The first in the pair is a request to be sent in a request-reply
communication model. The second is the reply appropriate to the
request.

message_formats.txt lists the 95 named message formats along with the
list of structures that constitue each. There is also an initial
discussion of what the message formats are and how they relate to
PtlRPC request message pairs.

structures.txt lists the 69 symbols (RMF_*) used to denote the
sequence of structures in the defnition of the message formats. The
file just associates the symbolic name used in the message format
defnition with the actual 'struct <name>' that defines its sequence of
fields. In some cases there is no struct associated with the RMF_
symbol. In those cases the associated bytes, if any, will have to have
their sematics explained directly.

struct_defs.txt details the fields in each of the structures named in
the structures.txt list along with the sematics for each field. The
special structure for the message header is included here.