diff options
Diffstat (limited to 'net/sunrpc/xprtrdma/svc_rdma_recvfrom.c')
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index b24d5b8f2fee..828b149eaaef 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -485,6 +485,68 @@ static __be32 *xdr_check_reply_chunk(__be32 *p, const __be32 *end) return p; } +/* RPC-over-RDMA Version One private extension: Remote Invalidation. + * Responder's choice: requester signals it can handle Send With + * Invalidate, and responder chooses one R_key to invalidate. + * + * If there is exactly one distinct R_key in the received transport + * header, set rc_inv_rkey to that R_key. Otherwise, set it to zero. + * + * Perform this operation while the received transport header is + * still in the CPU cache. + */ +static void svc_rdma_get_inv_rkey(struct svcxprt_rdma *rdma, + struct svc_rdma_recv_ctxt *ctxt) +{ + __be32 inv_rkey, *p; + u32 i, segcount; + + ctxt->rc_inv_rkey = 0; + + if (!rdma->sc_snd_w_inv) + return; + + inv_rkey = xdr_zero; + p = ctxt->rc_recv_buf; + p += rpcrdma_fixed_maxsz; + + /* Read list */ + while (*p++ != xdr_zero) { + p++; /* position */ + if (inv_rkey == xdr_zero) + inv_rkey = *p; + else if (inv_rkey != *p) + return; + p += 4; + } + + /* Write list */ + while (*p++ != xdr_zero) { + segcount = be32_to_cpup(p++); + for (i = 0; i < segcount; i++) { + if (inv_rkey == xdr_zero) + inv_rkey = *p; + else if (inv_rkey != *p) + return; + p += 4; + } + } + + /* Reply chunk */ + if (*p++ != xdr_zero) { + segcount = be32_to_cpup(p++); + for (i = 0; i < segcount; i++) { + if (inv_rkey == xdr_zero) + inv_rkey = *p; + else if (inv_rkey != *p) + return; + p += 4; + } + } + + ctxt->rc_inv_rkey = be32_to_cpu(inv_rkey); +} + /* On entry, xdr->head[0].iov_base points to first byte in the * RPC-over-RDMA header. * @@ -746,6 +808,7 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp) svc_rdma_recv_ctxt_put(rdma_xprt, ctxt); return ret; } + svc_rdma_get_inv_rkey(rdma_xprt, ctxt); p += rpcrdma_fixed_maxsz; if (*p != xdr_zero) |