diff options
| author | Chuck Lever <chuck.lever@oracle.com> | 2016-05-02 14:40:40 -0400 |
|---|---|---|
| committer | Anna Schumaker <Anna.Schumaker@Netapp.com> | 2016-05-17 15:47:57 -0400 |
| commit | 6b26cc8c8ead3636a18bfd9489984983f4ddd6f4 (patch) | |
| tree | a568d97b3fea0065f56122b1652ecc7748fa1da5 /net/sunrpc/xprtrdma/backchannel.c | |
| parent | 4b9c7f9db9a003f5c342184dc4401c1b7f2efb39 (diff) | |
sunrpc: Advertise maximum backchannel payload size
RPC-over-RDMA transports have a limit on how large a backward
direction (backchannel) RPC message can be. Ensure that the NFSv4.x
CREATE_SESSION operation advertises this limit to servers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Diffstat (limited to 'net/sunrpc/xprtrdma/backchannel.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/backchannel.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/backchannel.c b/net/sunrpc/xprtrdma/backchannel.c index 2dcd7640eeb5..87762d976b63 100644 --- a/net/sunrpc/xprtrdma/backchannel.c +++ b/net/sunrpc/xprtrdma/backchannel.c @@ -192,6 +192,22 @@ int xprt_rdma_bc_up(struct svc_serv *serv, struct net *net) } /** + * xprt_rdma_bc_maxpayload - Return maximum backchannel message size + * @xprt: transport + * + * Returns maximum size, in bytes, of a backchannel message + */ +size_t xprt_rdma_bc_maxpayload(struct rpc_xprt *xprt) +{ + struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt); + struct rpcrdma_create_data_internal *cdata = &r_xprt->rx_data; + size_t maxmsg; + + maxmsg = min_t(unsigned int, cdata->inline_rsize, cdata->inline_wsize); + return maxmsg - RPCRDMA_HDRLEN_MIN; +} + +/** * rpcrdma_bc_marshal_reply - Send backwards direction reply * @rqst: buffer containing RPC reply data * |