Merge tag 'nfsd-4.18' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "A relatively quiet cycle for nfsd.

  The largest piece is an RDMA update from Chuck Lever with new trace
  points, miscellaneous cleanups, and streamlining of the send and
  receive paths.

  Other than that, some miscellaneous bugfixes"

* tag 'nfsd-4.18' of git://linux-nfs.org/~bfields/linux: (26 commits)
  nfsd: fix error handling in nfs4_set_delegation()
  nfsd: fix potential use-after-free in nfsd4_decode_getdeviceinfo
  Fix 16-byte memory leak in gssp_accept_sec_context_upcall
  svcrdma: Fix incorrect return value/type in svc_rdma_post_recvs
  svcrdma: Remove unused svc_rdma_op_ctxt
  svcrdma: Persistently allocate and DMA-map Send buffers
  svcrdma: Simplify svc_rdma_send()
  svcrdma: Remove post_send_wr
  svcrdma: Don't overrun the SGE array in svc_rdma_send_ctxt
  svcrdma: Introduce svc_rdma_send_ctxt
  svcrdma: Clean up Send SGE accounting
  svcrdma: Refactor svc_rdma_dma_map_buf
  svcrdma: Allocate recv_ctxt's on CPU handling Receives
  svcrdma: Persistently allocate and DMA-map Receive buffers
  svcrdma: Preserve Receive buffer until svc_rdma_sendto
  svcrdma: Simplify svc_rdma_recv_ctxt_put
  svcrdma: Remove sc_rq_depth
  svcrdma: Introduce svc_rdma_recv_ctxt
  svcrdma: Trace key RDMA API events
  svcrdma: Trace key RPC/RDMA protocol events
  ...

1 files changed, 22 insertions, 32 deletions

diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index a73632ca9048..343e7add672c 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -1,13 +1,16 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- * Copyright (c) 2015 Oracle.  All rights reserved.
+ * Copyright (c) 2015-2018 Oracle.  All rights reserved.
  *
  * Support for backward direction RPCs on RPC/RDMA (server-side).
  */
 
 #include <linux/module.h>
+
 #include <linux/sunrpc/svc_rdma.h>
+
 #include "xprt_rdma.h"
+#include <trace/events/rpcrdma.h>
 
 #define RPCDBG_FACILITY	RPCDBG_SVCXPRT
 
@@ -112,39 +115,21 @@ out_notfound:
  * the adapter has a small maximum SQ depth.
  */
 static int svc_rdma_bc_sendto(struct svcxprt_rdma *rdma,
-			      struct rpc_rqst *rqst)
+			      struct rpc_rqst *rqst,
+			      struct svc_rdma_send_ctxt *ctxt)
 {
-	struct svc_rdma_op_ctxt *ctxt;
 	int ret;
 
-	ctxt = svc_rdma_get_context(rdma);
-
-	/* rpcrdma_bc_send_request builds the transport header and
-	 * the backchannel RPC message in the same buffer. Thus only
-	 * one SGE is needed to send both.
-	 */
-	ret = svc_rdma_map_reply_hdr(rdma, ctxt, rqst->rq_buffer,
-				     rqst->rq_snd_buf.len);
+	ret = svc_rdma_map_reply_msg(rdma, ctxt, &rqst->rq_snd_buf, NULL);
 	if (ret < 0)
-		goto out_err;
+		return -EIO;
 
 	/* Bump page refcnt so Send completion doesn't release
 	 * the rq_buffer before all retransmits are complete.
 	 */
 	get_page(virt_to_page(rqst->rq_buffer));
-	ret = svc_rdma_post_send_wr(rdma, ctxt, 1, 0);
-	if (ret)
-		goto out_unmap;
-
-out_err:
-	dprintk("svcrdma: %s returns %d\n", __func__, ret);
-	return ret;
-
-out_unmap:
-	svc_rdma_unmap_dma(ctxt);
-	svc_rdma_put_context(ctxt, 1);
-	ret = -EIO;
-	goto out_err;
+	ctxt->sc_send_wr.opcode = IB_WR_SEND;
+	return svc_rdma_send(rdma, &ctxt->sc_send_wr);
 }
 
 /* Server-side transport endpoint wants a whole page for its send
@@ -191,13 +176,15 @@ rpcrdma_bc_send_request(struct svcxprt_rdma *rdma, struct rpc_rqst *rqst)
 {
 	struct rpc_xprt *xprt = rqst->rq_xprt;
 	struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
+	struct svc_rdma_send_ctxt *ctxt;
 	__be32 *p;
 	int rc;
 
-	/* Space in the send buffer for an RPC/RDMA header is reserved
-	 * via xprt->tsh_size.
-	 */
-	p = rqst->rq_buffer;
+	ctxt = svc_rdma_send_ctxt_get(rdma);
+	if (!ctxt)
+		goto drop_connection;
+
+	p = ctxt->sc_xprt_buf;
 	*p++ = rqst->rq_xid;
 	*p++ = rpcrdma_version;
 	*p++ = cpu_to_be32(r_xprt->rx_buf.rb_bc_max_requests);
@@ -205,14 +192,17 @@ rpcrdma_bc_send_request(struct svcxprt_rdma *rdma, struct rpc_rqst *rqst)
 	*p++ = xdr_zero;
 	*p++ = xdr_zero;
 	*p   = xdr_zero;
+	svc_rdma_sync_reply_hdr(rdma, ctxt, RPCRDMA_HDRLEN_MIN);
 
 #ifdef SVCRDMA_BACKCHANNEL_DEBUG
 	pr_info("%s: %*ph\n", __func__, 64, rqst->rq_buffer);
 #endif
 
-	rc = svc_rdma_bc_sendto(rdma, rqst);
-	if (rc)
+	rc = svc_rdma_bc_sendto(rdma, rqst, ctxt);
+	if (rc) {
+		svc_rdma_send_ctxt_put(rdma, ctxt);
 		goto drop_connection;
+	}
 	return rc;
 
 drop_connection:
@@ -320,7 +310,7 @@ xprt_setup_rdma_bc(struct xprt_create *args)
 	xprt->idle_timeout = RPCRDMA_IDLE_DISC_TO;
 
 	xprt->prot = XPRT_TRANSPORT_BC_RDMA;
-	xprt->tsh_size = RPCRDMA_HDRLEN_MIN / sizeof(__be32);
+	xprt->tsh_size = 0;
 	xprt->ops = &xprt_rdma_bc_procs;
 
 	memcpy(&xprt->addr, args->dstaddr, args->addrlen);