Linux-libre 4.6.2-gnu

1 files changed, 78 insertions, 30 deletions

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index 0f28f2d74..888823bb6 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -132,6 +132,33 @@ rpcrdma_tail_pullup(struct xdr_buf *buf)
 	return tlen;
 }
 
+/* Split "vec" on page boundaries into segments. FMR registers pages,
+ * not a byte range. Other modes coalesce these segments into a single
+ * MR when they can.
+ */
+static int
+rpcrdma_convert_kvec(struct kvec *vec, struct rpcrdma_mr_seg *seg,
+		     int n, int nsegs)
+{
+	size_t page_offset;
+	u32 remaining;
+	char *base;
+
+	base = vec->iov_base;
+	page_offset = offset_in_page(base);
+	remaining = vec->iov_len;
+	while (remaining && n < nsegs) {
+		seg[n].mr_page = NULL;
+		seg[n].mr_offset = base;
+		seg[n].mr_len = min_t(u32, PAGE_SIZE - page_offset, remaining);
+		remaining -= seg[n].mr_len;
+		base += seg[n].mr_len;
+		++n;
+		page_offset = 0;
+	}
+	return n;
+}
+
 /*
  * Chunk assembly from upper layer xdr_buf.
  *
@@ -150,11 +177,10 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos,
 	int page_base;
 	struct page **ppages;
 
-	if (pos == 0 && xdrbuf->head[0].iov_len) {
-		seg[n].mr_page = NULL;
-		seg[n].mr_offset = xdrbuf->head[0].iov_base;
-		seg[n].mr_len = xdrbuf->head[0].iov_len;
-		++n;
+	if (pos == 0) {
+		n = rpcrdma_convert_kvec(&xdrbuf->head[0], seg, n, nsegs);
+		if (n == nsegs)
+			return -EIO;
 	}
 
 	len = xdrbuf->page_len;
@@ -192,13 +218,9 @@ rpcrdma_convert_iovs(struct xdr_buf *xdrbuf, unsigned int pos,
 		 * xdr pad bytes, saving the server an RDMA operation. */
 		if (xdrbuf->tail[0].iov_len < 4 && xprt_rdma_pad_optimize)
 			return n;
+		n = rpcrdma_convert_kvec(&xdrbuf->tail[0], seg, n, nsegs);
 		if (n == nsegs)
-			/* Tail remains, but we're out of segments */
 			return -EIO;
-		seg[n].mr_page = NULL;
-		seg[n].mr_offset = xdrbuf->tail[0].iov_base;
-		seg[n].mr_len = xdrbuf->tail[0].iov_len;
-		++n;
 	}
 
 	return n;
@@ -773,20 +795,17 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 	struct rpcrdma_xprt *r_xprt = rep->rr_rxprt;
 	struct rpc_xprt *xprt = &r_xprt->rx_xprt;
 	__be32 *iptr;
-	int rdmalen, status;
+	int rdmalen, status, rmerr;
 	unsigned long cwnd;
-	u32 credits;
 
 	dprintk("RPC:       %s: incoming rep %p\n", __func__, rep);
 
 	if (rep->rr_len == RPCRDMA_BAD_LEN)
 		goto out_badstatus;
-	if (rep->rr_len < RPCRDMA_HDRLEN_MIN)
+	if (rep->rr_len < RPCRDMA_HDRLEN_ERR)
 		goto out_shortreply;
 
 	headerp = rdmab_to_msg(rep->rr_rdmabuf);
-	if (headerp->rm_vers != rpcrdma_version)
-		goto out_badversion;
 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
 	if (rpcrdma_is_bcall(headerp))
 		goto out_bcall;
@@ -809,15 +828,16 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 	 */
 	list_del_init(&rqst->rq_list);
 	spin_unlock_bh(&xprt->transport_lock);
-	dprintk("RPC:       %s: reply 0x%p completes request 0x%p\n"
-		"                   RPC request 0x%p xid 0x%08x\n",
-			__func__, rep, req, rqst,
-			be32_to_cpu(headerp->rm_xid));
+	dprintk("RPC:       %s: reply %p completes request %p (xid 0x%08x)\n",
+		__func__, rep, req, be32_to_cpu(headerp->rm_xid));
 
 	/* from here on, the reply is no longer an orphan */
 	req->rl_reply = rep;
 	xprt->reestablish_timeout = 0;
 
+	if (headerp->rm_vers != rpcrdma_version)
+		goto out_badversion;
+
 	/* check for expected message types */
 	/* The order of some of these tests is important. */
 	switch (headerp->rm_type) {
@@ -878,6 +898,9 @@ rpcrdma_reply_handler(struct rpcrdma_rep *rep)
 		status = rdmalen;
 		break;
 
+	case rdma_error:
+		goto out_rdmaerr;
+
 badheader:
 	default:
 		dprintk("%s: invalid rpcrdma reply header (type %d):"
@@ -893,6 +916,7 @@ badheader:
 		break;
 	}
 
+out:
 	/* Invalidate and flush the data payloads before waking the
 	 * waiting application. This guarantees the memory region is
 	 * properly fenced from the server before the application
@@ -903,15 +927,9 @@ badheader:
 	if (req->rl_nchunks)
 		r_xprt->rx_ia.ri_ops->ro_unmap_sync(r_xprt, req);
 
-	credits = be32_to_cpu(headerp->rm_credit);
-	if (credits == 0)
-		credits = 1;	/* don't deadlock */
-	else if (credits > r_xprt->rx_buf.rb_max_requests)
-		credits = r_xprt->rx_buf.rb_max_requests;
-
 	spin_lock_bh(&xprt->transport_lock);
 	cwnd = xprt->cwnd;
-	xprt->cwnd = credits << RPC_CWNDSHIFT;
+	xprt->cwnd = atomic_read(&r_xprt->rx_buf.rb_credits) << RPC_CWNDSHIFT;
 	if (xprt->cwnd > cwnd)
 		xprt_release_rqst_cong(rqst->rq_task);
 
@@ -935,13 +953,43 @@ out_bcall:
 	return;
 #endif
 
-out_shortreply:
-	dprintk("RPC:       %s: short/invalid reply\n", __func__);
-	goto repost;
-
+/* If the incoming reply terminated a pending RPC, the next
+ * RPC call will post a replacement receive buffer as it is
+ * being marshaled.
+ */
 out_badversion:
 	dprintk("RPC:       %s: invalid version %d\n",
 		__func__, be32_to_cpu(headerp->rm_vers));
+	status = -EIO;
+	r_xprt->rx_stats.bad_reply_count++;
+	goto out;
+
+out_rdmaerr:
+	rmerr = be32_to_cpu(headerp->rm_body.rm_error.rm_err);
+	switch (rmerr) {
+	case ERR_VERS:
+		pr_err("%s: server reports header version error (%u-%u)\n",
+		       __func__,
+		       be32_to_cpu(headerp->rm_body.rm_error.rm_vers_low),
+		       be32_to_cpu(headerp->rm_body.rm_error.rm_vers_high));
+		break;
+	case ERR_CHUNK:
+		pr_err("%s: server reports header decoding error\n",
+		       __func__);
+		break;
+	default:
+		pr_err("%s: server reports unknown error %d\n",
+		       __func__, rmerr);
+	}
+	status = -EREMOTEIO;
+	r_xprt->rx_stats.bad_reply_count++;
+	goto out;
+
+/* If no pending RPC transaction was matched, post a replacement
+ * receive buffer before returning.
+ */
+out_shortreply:
+	dprintk("RPC:       %s: short/invalid reply\n", __func__);
 	goto repost;
 
 out_nomatch: