svcrdma: Modify the RPC recv path to use FRMR when available
RPCRDMA requests that specify a read-list are fetched with RDMA_READ. Using
an FRMR to map the data sink improves NFSRDMA security on transports that
place the RDMA_READ data sink LKEY on the wire because the valid lifetime
of the MR is only the duration of the RDMA_READ. The LKEY is invalidated
when the last RDMA_READ WR completes.
Mapping the data sink also allows for very large amounts to data to be
fetched with a single WR, so if the client is also using FRMR, the entire
RPC read-list can be fetched with a single WR.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index f22f587..fb0dff5 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -105,7 +105,7 @@
return ctxt;
}
-static void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
+void svc_rdma_unmap_dma(struct svc_rdma_op_ctxt *ctxt)
{
struct svcxprt_rdma *xprt = ctxt->xprt;
int i;
@@ -343,9 +343,12 @@
break;
case IB_WR_RDMA_READ:
+ case IB_WR_RDMA_READ_WITH_INV:
if (test_bit(RDMACTXT_F_LAST_CTXT, &ctxt->flags)) {
struct svc_rdma_op_ctxt *read_hdr = ctxt->read_hdr;
BUG_ON(!read_hdr);
+ if (test_bit(RDMACTXT_F_FAST_UNREG, &ctxt->flags))
+ svc_rdma_put_frmr(xprt, ctxt->frmr);
spin_lock_bh(&xprt->sc_rq_dto_lock);
set_bit(XPT_DATA, &xprt->sc_xprt.xpt_flags);
list_add_tail(&read_hdr->dto_q,