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>

1 files changed, 70 insertions, 20 deletions

diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c
index 6b25bf816f28..a9b4ed4d7b52 100644
--- a/drivers/ntb/hw/intel/ntb_hw_intel.c
+++ b/drivers/ntb/hw/intel/ntb_hw_intel.c
@@ -6,6 +6,7 @@
  *
  *   Copyright(c) 2012 Intel Corporation. All rights reserved.
  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2016 T-Platforms. All Rights Reserved.
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of version 2 of the GNU General Public License as
@@ -15,6 +16,7 @@
  *
  *   Copyright(c) 2012 Intel Corporation. All rights reserved.
  *   Copyright (C) 2015 EMC Corporation. All Rights Reserved.
+ *   Copyright (C) 2016 T-Platforms. All Rights Reserved.
  *
  *   Redistribution and use in source and binary forms, with or without
  *   modification, are permitted provided that the following conditions
@@ -1035,20 +1037,26 @@ static void ndev_deinit_debugfs(struct intel_ntb_dev *ndev)
 	debugfs_remove_recursive(ndev->debugfs_dir);
 }
 
-static int intel_ntb_mw_count(struct ntb_dev *ntb)
+static int intel_ntb_mw_count(struct ntb_dev *ntb, int pidx)
 {
+	if (pidx != NTB_DEF_PEER_IDX)
+		return -EINVAL;
+
 	return ntb_ndev(ntb)->mw_count;
 }
 
-static int intel_ntb_mw_get_range(struct ntb_dev *ntb, int idx,
-				  phys_addr_t *base,
-				  resource_size_t *size,
-				  resource_size_t *align,
-				  resource_size_t *align_size)
+static int intel_ntb_mw_get_align(struct ntb_dev *ntb, int pidx, int idx,
+				  resource_size_t *addr_align,
+				  resource_size_t *size_align,
+				  resource_size_t *size_max)
 {
 	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+	resource_size_t bar_size, mw_size;
 	int bar;
 
+	if (pidx != NTB_DEF_PEER_IDX)
+		return -EINVAL;
+
 	if (idx >= ndev->b2b_idx && !ndev->b2b_off)
 		idx += 1;
 
@@ -1056,24 +1064,26 @@ static int intel_ntb_mw_get_range(struct ntb_dev *ntb, int idx,
 	if (bar < 0)
 		return bar;
 
-	if (base)
-		*base = pci_resource_start(ndev->ntb.pdev, bar) +
-			(idx == ndev->b2b_idx ? ndev->b2b_off : 0);
+	bar_size = pci_resource_len(ndev->ntb.pdev, bar);
 
-	if (size)
-		*size = pci_resource_len(ndev->ntb.pdev, bar) -
-			(idx == ndev->b2b_idx ? ndev->b2b_off : 0);
+	if (idx == ndev->b2b_idx)
+		mw_size = bar_size - ndev->b2b_off;
+	else
+		mw_size = bar_size;
+
+	if (addr_align)
+		*addr_align = pci_resource_len(ndev->ntb.pdev, bar);
 
-	if (align)
-		*align = pci_resource_len(ndev->ntb.pdev, bar);
+	if (size_align)
+		*size_align = 1;
 
-	if (align_size)
-		*align_size = 1;
+	if (size_max)
+		*size_max = mw_size;
 
 	return 0;
 }
 
-static int intel_ntb_mw_set_trans(struct ntb_dev *ntb, int idx,
+static int intel_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int idx,
 				  dma_addr_t addr, resource_size_t size)
 {
 	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
@@ -1083,6 +1093,9 @@ static int intel_ntb_mw_set_trans(struct ntb_dev *ntb, int idx,
 	u64 base, limit, reg_val;
 	int bar;
 
+	if (pidx != NTB_DEF_PEER_IDX)
+		return -EINVAL;
+
 	if (idx >= ndev->b2b_idx && !ndev->b2b_off)
 		idx += 1;
 
@@ -1249,6 +1262,36 @@ static int intel_ntb_link_disable(struct ntb_dev *ntb)
 	return 0;
 }
 
+static int intel_ntb_peer_mw_count(struct ntb_dev *ntb)
+{
+	/* Numbers of inbound and outbound memory windows match */
+	return ntb_ndev(ntb)->mw_count;
+}
+
+static int intel_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int idx,
+				     phys_addr_t *base, resource_size_t *size)
+{
+	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
+	int bar;
+
+	if (idx >= ndev->b2b_idx && !ndev->b2b_off)
+		idx += 1;
+
+	bar = ndev_mw_to_bar(ndev, idx);
+	if (bar < 0)
+		return bar;
+
+	if (base)
+		*base = pci_resource_start(ndev->ntb.pdev, bar) +
+			(idx == ndev->b2b_idx ? ndev->b2b_off : 0);
+
+	if (size)
+		*size = pci_resource_len(ndev->ntb.pdev, bar) -
+			(idx == ndev->b2b_idx ? ndev->b2b_off : 0);
+
+	return 0;
+}
+
 static int intel_ntb_db_is_unsafe(struct ntb_dev *ntb)
 {
 	return ndev_ignore_unsafe(ntb_ndev(ntb), NTB_UNSAFE_DB);
@@ -1902,7 +1945,7 @@ static int intel_ntb3_link_enable(struct ntb_dev *ntb,
 
 	return 0;
 }
-static int intel_ntb3_mw_set_trans(struct ntb_dev *ntb, int idx,
+static int intel_ntb3_mw_set_trans(struct ntb_dev *ntb, int pidx, int idx,
 				   dma_addr_t addr, resource_size_t size)
 {
 	struct intel_ntb_dev *ndev = ntb_ndev(ntb);
@@ -1912,6 +1955,9 @@ static int intel_ntb3_mw_set_trans(struct ntb_dev *ntb, int idx,
 	u64 base, limit, reg_val;
 	int bar;
 
+	if (pidx != NTB_DEF_PEER_IDX)
+		return -EINVAL;
+
 	if (idx >= ndev->b2b_idx && !ndev->b2b_off)
 		idx += 1;
 
@@ -2906,8 +2952,10 @@ static const struct intel_ntb_xlat_reg skx_sec_xlat = {
 /* operations for primary side of local ntb */
 static const struct ntb_dev_ops intel_ntb_ops = {
 	.mw_count		= intel_ntb_mw_count,
-	.mw_get_range		= intel_ntb_mw_get_range,
+	.mw_get_align		= intel_ntb_mw_get_align,
 	.mw_set_trans		= intel_ntb_mw_set_trans,
+	.peer_mw_count		= intel_ntb_peer_mw_count,
+	.peer_mw_get_addr	= intel_ntb_peer_mw_get_addr,
 	.link_is_up		= intel_ntb_link_is_up,
 	.link_enable		= intel_ntb_link_enable,
 	.link_disable		= intel_ntb_link_disable,
@@ -2932,8 +2980,10 @@ static const struct ntb_dev_ops intel_ntb_ops = {
 
 static const struct ntb_dev_ops intel_ntb3_ops = {
 	.mw_count		= intel_ntb_mw_count,
-	.mw_get_range		= intel_ntb_mw_get_range,
+	.mw_get_align		= intel_ntb_mw_get_align,
 	.mw_set_trans		= intel_ntb3_mw_set_trans,
+	.peer_mw_count		= intel_ntb_peer_mw_count,
+	.peer_mw_get_addr	= intel_ntb_peer_mw_get_addr,
 	.link_is_up		= intel_ntb_link_is_up,
 	.link_enable		= intel_ntb3_link_enable,
 	.link_disable		= intel_ntb_link_disable,