vdpa/mlx5: Add support for control VQ and MAC setting

Add support to handle control virtqueue configurations per virtio
specification. The control virtqueue is implemented in software and no
hardware offloading is involved.

Control VQ configuration need task context, therefore all configurations
are handled in a workqueue created for the purpose.

Modifications are made to the memory registration code to allow for
saving a copy of itolb to be used by the control VQ to access the vring.

The max number of data virtqueus supported by the driver has been
updated to 2 since multiqueue is not supported at this stage and we need
to ensure consistency of VQ indices mapping to either data or control
VQ.

Signed-off-by: Eli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210823052123.14909-6-elic@nvidia.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 61 insertions, 20 deletions

diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
index e59135fa867e..ff010c6d0cd3 100644
--- a/drivers/vdpa/mlx5/core/mr.c
+++ b/drivers/vdpa/mlx5/core/mr.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
 /* Copyright (c) 2020 Mellanox Technologies Ltd. */
 
+#include <linux/vhost_types.h>
 #include <linux/vdpa.h>
 #include <linux/gcd.h>
 #include <linux/string.h>
@@ -451,33 +452,30 @@ static void destroy_dma_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
 	mlx5_vdpa_destroy_mkey(mvdev, &mr->mkey);
 }
 
-static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+static int dup_iotlb(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *src)
 {
-	struct mlx5_vdpa_mr *mr = &mvdev->mr;
+	struct vhost_iotlb_map *map;
+	u64 start = 0, last = ULLONG_MAX;
 	int err;
 
-	if (mr->initialized)
-		return 0;
-
-	if (iotlb)
-		err = create_user_mr(mvdev, iotlb);
-	else
-		err = create_dma_mr(mvdev, mr);
-
-	if (!err)
-		mr->initialized = true;
+	if (!src) {
+		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, start, last, start, VHOST_ACCESS_RW);
+		return err;
+	}
 
-	return err;
+	for (map = vhost_iotlb_itree_first(src, start, last); map;
+		map = vhost_iotlb_itree_next(map, start, last)) {
+		err = vhost_iotlb_add_range(mvdev->cvq.iotlb, map->start, map->last,
+					    map->addr, map->perm);
+		if (err)
+			return err;
+	}
+	return 0;
 }
 
-int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+static void prune_iotlb(struct mlx5_vdpa_dev *mvdev)
 {
-	int err;
-
-	mutex_lock(&mvdev->mr.mkey_mtx);
-	err = _mlx5_vdpa_create_mr(mvdev, iotlb);
-	mutex_unlock(&mvdev->mr.mkey_mtx);
-	return err;
+	vhost_iotlb_del_range(mvdev->cvq.iotlb, 0, ULLONG_MAX);
 }
 
 static void destroy_user_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr)
@@ -501,6 +499,7 @@ void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev)
 	if (!mr->initialized)
 		goto out;
 
+	prune_iotlb(mvdev);
 	if (mr->user_mr)
 		destroy_user_mr(mvdev, mr);
 	else
@@ -512,6 +511,48 @@ out:
 	mutex_unlock(&mr->mkey_mtx);
 }
 
+static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+{
+	struct mlx5_vdpa_mr *mr = &mvdev->mr;
+	int err;
+
+	if (mr->initialized)
+		return 0;
+
+	if (iotlb)
+		err = create_user_mr(mvdev, iotlb);
+	else
+		err = create_dma_mr(mvdev, mr);
+
+	if (err)
+		return err;
+
+	err = dup_iotlb(mvdev, iotlb);
+	if (err)
+		goto out_err;
+
+	mr->initialized = true;
+	return 0;
+
+out_err:
+	if (iotlb)
+		destroy_user_mr(mvdev, mr);
+	else
+		destroy_dma_mr(mvdev, mr);
+
+	return err;
+}
+
+int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb)
+{
+	int err;
+
+	mutex_lock(&mvdev->mr.mkey_mtx);
+	err = _mlx5_vdpa_create_mr(mvdev, iotlb);
+	mutex_unlock(&mvdev->mr.mkey_mtx);
+	return err;
+}
+
 int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
 			     bool *change_map)
 {