xprtrdma: Basic support for Remote Invalidation
Have frwr's ro_unmap_sync recognize an invalidated rkey that appears
as part of a Receive completion. Local invalidation can be skipped
for that rkey.
Use an out-of-band signaling mechanism to indicate to the server
that the client is prepared to receive RDMA Send With Invalidate.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index ea734c2..31a434d 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -231,7 +231,8 @@
static int
rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos,
- enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg)
+ enum rpcrdma_chunktype type, struct rpcrdma_mr_seg *seg,
+ bool reminv_expected)
{
int len, n, p, page_base;
struct page **ppages;
@@ -273,6 +274,13 @@
if (type == rpcrdma_readch)
return n;
+ /* When encoding the Write list, some servers need to see an extra
+ * segment for odd-length Write chunks. The upper layer provides
+ * space in the tail iovec for this purpose.
+ */
+ if (type == rpcrdma_writech && reminv_expected)
+ return n;
+
if (xdrbuf->tail[0].iov_len) {
/* the rpcrdma protocol allows us to omit any trailing
* xdr pad bytes, saving the server an RDMA operation. */
@@ -329,7 +337,7 @@
if (rtype == rpcrdma_areadch)
pos = 0;
seg = req->rl_segments;
- nsegs = rpcrdma_convert_iovs(&rqst->rq_snd_buf, pos, rtype, seg);
+ nsegs = rpcrdma_convert_iovs(&rqst->rq_snd_buf, pos, rtype, seg, false);
if (nsegs < 0)
return ERR_PTR(nsegs);
@@ -393,7 +401,8 @@
seg = req->rl_segments;
nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf,
rqst->rq_rcv_buf.head[0].iov_len,
- wtype, seg);
+ wtype, seg,
+ r_xprt->rx_ia.ri_reminv_expected);
if (nsegs < 0)
return ERR_PTR(nsegs);
@@ -458,7 +467,8 @@
}
seg = req->rl_segments;
- nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf, 0, wtype, seg);
+ nsegs = rpcrdma_convert_iovs(&rqst->rq_rcv_buf, 0, wtype, seg,
+ r_xprt->rx_ia.ri_reminv_expected);
if (nsegs < 0)
return ERR_PTR(nsegs);