NTB: Alter MW API to support multi-ports devices

Multi-port NTB devices permit to share a memory between all accessible peers.
Memory Windows API is altered to correspondingly initialize and map memory
windows for such devices:
 ntb_mw_count(pidx); - number of inbound memory windows, which can be allocated
for shared buffer with specified peer device.
 ntb_mw_get_align(pidx, widx); - get alignment and size restriction parameters
to properly allocate inbound memory region.
 ntb_peer_mw_count(); - get number of outbound memory windows.
 ntb_peer_mw_get_addr(widx); - get mapping address of an outbound memory window

If hardware supports inbound translation configured on the local ntb port:
 ntb_mw_set_trans(pidx, widx); - set translation address of allocated inbound
memory window so a peer device could access it.
 ntb_mw_clear_trans(pidx, widx); - clear the translation address of an inbound
memory window.

If hardware supports outbound translation configured on the peer ntb port:
 ntb_peer_mw_set_trans(pidx, widx); - set translation address of a memory
window retrieved from a peer device
 ntb_peer_mw_clear_trans(pidx, widx); - clear the translation address of an
outbound memory window

Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Acked-by: Allen Hubbe <Allen.Hubbe@dell.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

drivers/ntb/ntb_transport.c

@@ -673,7 +673,7 @@ static void ntb_free_mw(struct ntb_transport_ctx *nt, int num_mw)
 	if (!mw->virt_addr)
 		return;
 
-	ntb_mw_clear_trans(nt->ndev, num_mw);
+	ntb_mw_clear_trans(nt->ndev, PIDX, num_mw);
 	dma_free_coherent(&pdev->dev, mw->buff_size,
 			  mw->virt_addr, mw->dma_addr);
 	mw->xlat_size = 0;
@@ -730,7 +730,8 @@ static int ntb_set_mw(struct ntb_transport_ctx *nt, int num_mw,
 	}
 
 	/* Notify HW the memory location of the receive buffer */
-	rc = ntb_mw_set_trans(nt->ndev, num_mw, mw->dma_addr, mw->xlat_size);
+	rc = ntb_mw_set_trans(nt->ndev, PIDX, num_mw, mw->dma_addr,
+			      mw->xlat_size);
 	if (rc) {
 		dev_err(&pdev->dev, "Unable to set mw%d translation", num_mw);
 		ntb_free_mw(nt, num_mw);
@@ -1058,7 +1059,12 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev)
 	int node;
 	int rc, i;
 
-	mw_count = ntb_mw_count(ndev);
+	mw_count = ntb_mw_count(ndev, PIDX);
+
+	if (!ndev->ops->mw_set_trans) {
+		dev_err(&ndev->dev, "Inbound MW based NTB API is required\n");
+		return -EINVAL;
+	}
 
 	if (ntb_db_is_unsafe(ndev))
 		dev_dbg(&ndev->dev,
@@ -1100,8 +1106,13 @@ static int ntb_transport_probe(struct ntb_client *self, struct ntb_dev *ndev)
 	for (i = 0; i < mw_count; i++) {
 		mw = &nt->mw_vec[i];
 
-		rc = ntb_mw_get_range(ndev, i, &mw->phys_addr, &mw->phys_size,
-				      &mw->xlat_align, &mw->xlat_align_size);
+		rc = ntb_mw_get_align(ndev, PIDX, i, &mw->xlat_align,
+				      &mw->xlat_align_size, NULL);
+		if (rc)
+			goto err1;
+
+		rc = ntb_peer_mw_get_addr(ndev, i, &mw->phys_addr,
+					  &mw->phys_size);
 		if (rc)
 			goto err1;