[PATCH vhost 13/16] vdpa/mlx5: Introduce mr for vq descriptor

From: Dragos Tatulea
Date: Thu Sep 28 2023 - 12:50:56 EST


Introduce the vq descriptor group and ASID 1. Until now .set_map on ASID
1 was only updating the cvq iotlb. From now on it also creates a mkey
for it. The current patch doesn't use it but follow-up patches will
add hardware support for mapping the vq descriptors.

Signed-off-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
---
drivers/vdpa/mlx5/core/mlx5_vdpa.h | 5 +++--
drivers/vdpa/mlx5/core/mr.c | 14 +++++++++-----
drivers/vdpa/mlx5/net/mlx5_vnet.c | 20 +++++++++++++-------
3 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index bbe4335106bd..ae09296f4270 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -70,11 +70,12 @@ struct mlx5_vdpa_wq_ent {
enum {
MLX5_VDPA_DATAVQ_GROUP,
MLX5_VDPA_CVQ_GROUP,
+ MLX5_VDPA_DATAVQ_DESC_GROUP,
MLX5_VDPA_NUMVQ_GROUPS
};

enum {
- MLX5_VDPA_NUM_AS = MLX5_VDPA_NUMVQ_GROUPS
+ MLX5_VDPA_NUM_AS = 2
};

struct mlx5_vdpa_dev {
@@ -89,7 +90,7 @@ struct mlx5_vdpa_dev {
u16 max_idx;
u32 generation;

- struct mlx5_vdpa_mr *mr;
+ struct mlx5_vdpa_mr *mr[MLX5_VDPA_NUM_AS];
/* serialize mr access */
struct mutex mr_mtx;
struct mlx5_control_vq cvq;
diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c
index 00eff5a07152..3dee6d9bed6b 100644
--- a/drivers/vdpa/mlx5/core/mr.c
+++ b/drivers/vdpa/mlx5/core/mr.c
@@ -511,8 +511,10 @@ void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev,

_mlx5_vdpa_destroy_mr(mvdev, mr);

- if (mvdev->mr == mr)
- mvdev->mr = NULL;
+ for (int i = 0; i < MLX5_VDPA_NUM_AS; i++) {
+ if (mvdev->mr[i] == mr)
+ mvdev->mr[i] = NULL;
+ }

mutex_unlock(&mvdev->mr_mtx);

@@ -523,11 +525,11 @@ void mlx5_vdpa_update_mr(struct mlx5_vdpa_dev *mvdev,
struct mlx5_vdpa_mr *new_mr,
unsigned int asid)
{
- struct mlx5_vdpa_mr *old_mr = mvdev->mr;
+ struct mlx5_vdpa_mr *old_mr = mvdev->mr[asid];

mutex_lock(&mvdev->mr_mtx);

- mvdev->mr = new_mr;
+ mvdev->mr[asid] = new_mr;
if (old_mr) {
_mlx5_vdpa_destroy_mr(mvdev, old_mr);
kfree(old_mr);
@@ -539,7 +541,9 @@ void mlx5_vdpa_update_mr(struct mlx5_vdpa_dev *mvdev,

void mlx5_vdpa_destroy_mr_resources(struct mlx5_vdpa_dev *mvdev)
{
- mlx5_vdpa_destroy_mr(mvdev, mvdev->mr);
+ for (int i = 0; i < MLX5_VDPA_NUM_AS; i++)
+ mlx5_vdpa_destroy_mr(mvdev, mvdev->mr[i]);
+
prune_iotlb(mvdev);
}

diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 4a87f9119fca..25bd2c324f5b 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -821,6 +821,8 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
{
int inlen = MLX5_ST_SZ_BYTES(create_virtio_net_q_in);
u32 out[MLX5_ST_SZ_DW(create_virtio_net_q_out)] = {};
+ struct mlx5_vdpa_dev *mvdev = &ndev->mvdev;
+ struct mlx5_vdpa_mr *vq_mr;
void *obj_context;
u16 mlx_features;
void *cmd_hdr;
@@ -873,7 +875,9 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
MLX5_SET64(virtio_q, vq_ctx, desc_addr, mvq->desc_addr);
MLX5_SET64(virtio_q, vq_ctx, used_addr, mvq->device_addr);
MLX5_SET64(virtio_q, vq_ctx, available_addr, mvq->driver_addr);
- MLX5_SET(virtio_q, vq_ctx, virtio_q_mkey, ndev->mvdev.mr->mkey);
+ vq_mr = mvdev->mr[mvdev->group2asid[MLX5_VDPA_DATAVQ_GROUP]];
+ if (vq_mr)
+ MLX5_SET(virtio_q, vq_ctx, virtio_q_mkey, vq_mr->mkey);
MLX5_SET(virtio_q, vq_ctx, umem_1_id, mvq->umem1.id);
MLX5_SET(virtio_q, vq_ctx, umem_1_size, mvq->umem1.size);
MLX5_SET(virtio_q, vq_ctx, umem_2_id, mvq->umem2.id);
@@ -2633,7 +2637,8 @@ static void restore_channels_info(struct mlx5_vdpa_net *ndev)
}

static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev,
- struct mlx5_vdpa_mr *new_mr, unsigned int asid)
+ struct mlx5_vdpa_mr *new_mr,
+ unsigned int asid)
{
struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
int err;
@@ -2652,8 +2657,10 @@ static int mlx5_vdpa_change_map(struct mlx5_vdpa_dev *mvdev,

restore_channels_info(ndev);
err = setup_driver(mvdev);
+ if (err)
+ return err;

- return err;
+ return 0;
}

/* reslock must be held for this function */
@@ -2869,8 +2876,8 @@ static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
struct mlx5_vdpa_mr *new_mr;
int err;

- if (mvdev->group2asid[MLX5_VDPA_DATAVQ_GROUP] != asid)
- goto end;
+ if (asid >= MLX5_VDPA_NUM_AS)
+ return -EINVAL;

new_mr = mlx5_vdpa_create_mr(mvdev, iotlb);
if (IS_ERR(new_mr)) {
@@ -2879,7 +2886,7 @@ static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
return err;
}

- if (!mvdev->mr) {
+ if (!mvdev->mr[asid]) {
mlx5_vdpa_update_mr(mvdev, new_mr, asid);
} else {
err = mlx5_vdpa_change_map(mvdev, new_mr, asid);
@@ -2889,7 +2896,6 @@ static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
}
}

-end:
return mlx5_vdpa_update_cvq_iotlb(mvdev, iotlb, asid);

out_err:
--
2.41.0