[PATCH 5.0 19/52] net/mlx5: Fix DCT creation bad flow

[Greg Kroah-Hartman]

5.0-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Yishai Hadas <yishaih@xxxxxxxxxxxx>

commit f84b66b9cce78e8f9d38204fdaa75f07c75f4911 upstream.

In case the DCT creation command has succeeded a DRAIN must be issued
before calling DESTROY.

In addition, the original code used the wrong parameter for the DESTROY
command, 'in' instead of 'din', which caused another creation try instead
of destroying.

Cc: <stable@xxxxxxxxxxxxxxx> # 4.15
Fixes: 57cda166bbe0 ("net/mlx5: Add DCT command interface")
Signed-off-by: Yishai Hadas <yishaih@xxxxxxxxxxxx>
Reviewed-by: Artemy Kovalyov <artemyko@xxxxxxxxxxxx>
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/ethernet/mellanox/mlx5/core/qp.c |   66 ++++++++++++++-------------
 1 file changed, 36 insertions(+), 30 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/qp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/qp.c
@@ -40,6 +40,9 @@
 #include "mlx5_core.h"
 #include "lib/eq.h"
 
+static int mlx5_core_drain_dct(struct mlx5_core_dev *dev,
+			       struct mlx5_core_dct *dct);
+
 static struct mlx5_core_rsc_common *
 mlx5_get_rsc(struct mlx5_qp_table *table, u32 rsn)
 {
@@ -227,13 +230,42 @@ static void destroy_resource_common(stru
 	wait_for_completion(&qp->common.free);
 }
 
+static int _mlx5_core_destroy_dct(struct mlx5_core_dev *dev,
+				  struct mlx5_core_dct *dct, bool need_cleanup)
+{
+	u32 out[MLX5_ST_SZ_DW(destroy_dct_out)] = {0};
+	u32 in[MLX5_ST_SZ_DW(destroy_dct_in)]   = {0};
+	struct mlx5_core_qp *qp = &dct->mqp;
+	int err;
+
+	err = mlx5_core_drain_dct(dev, dct);
+	if (err) {
+		if (dev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR) {
+			goto destroy;
+		} else {
+			mlx5_core_warn(
+				dev, "failed drain DCT 0x%x with error 0x%x\n",
+				qp->qpn, err);
+			return err;
+		}
+	}
+	wait_for_completion(&dct->drained);
+destroy:
+	if (need_cleanup)
+		destroy_resource_common(dev, &dct->mqp);
+	MLX5_SET(destroy_dct_in, in, opcode, MLX5_CMD_OP_DESTROY_DCT);
+	MLX5_SET(destroy_dct_in, in, dctn, qp->qpn);
+	MLX5_SET(destroy_dct_in, in, uid, qp->uid);
+	err = mlx5_cmd_exec(dev, (void *)&in, sizeof(in),
+			    (void *)&out, sizeof(out));
+	return err;
+}
+
 int mlx5_core_create_dct(struct mlx5_core_dev *dev,
 			 struct mlx5_core_dct *dct,
 			 u32 *in, int inlen)
 {
 	u32 out[MLX5_ST_SZ_DW(create_dct_out)]   = {0};
-	u32 din[MLX5_ST_SZ_DW(destroy_dct_in)]   = {0};
-	u32 dout[MLX5_ST_SZ_DW(destroy_dct_out)] = {0};
 	struct mlx5_core_qp *qp = &dct->mqp;
 	int err;
 
@@ -254,11 +286,7 @@ int mlx5_core_create_dct(struct mlx5_cor
 
 	return 0;
 err_cmd:
-	MLX5_SET(destroy_dct_in, din, opcode, MLX5_CMD_OP_DESTROY_DCT);
-	MLX5_SET(destroy_dct_in, din, dctn, qp->qpn);
-	MLX5_SET(destroy_dct_in, din, uid, qp->uid);
-	mlx5_cmd_exec(dev, (void *)&in, sizeof(din),
-		      (void *)&out, sizeof(dout));
+	_mlx5_core_destroy_dct(dev, dct, false);
 	return err;
 }
 EXPORT_SYMBOL_GPL(mlx5_core_create_dct);
@@ -323,29 +351,7 @@ static int mlx5_core_drain_dct(struct ml
 int mlx5_core_destroy_dct(struct mlx5_core_dev *dev,
 			  struct mlx5_core_dct *dct)
 {
-	u32 out[MLX5_ST_SZ_DW(destroy_dct_out)] = {0};
-	u32 in[MLX5_ST_SZ_DW(destroy_dct_in)]   = {0};
-	struct mlx5_core_qp *qp = &dct->mqp;
-	int err;
-
-	err = mlx5_core_drain_dct(dev, dct);
-	if (err) {
-		if (dev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR) {
-			goto destroy;
-		} else {
-			mlx5_core_warn(dev, "failed drain DCT 0x%x with error 0x%x\n", qp->qpn, err);
-			return err;
-		}
-	}
-	wait_for_completion(&dct->drained);
-destroy:
-	destroy_resource_common(dev, &dct->mqp);
-	MLX5_SET(destroy_dct_in, in, opcode, MLX5_CMD_OP_DESTROY_DCT);
-	MLX5_SET(destroy_dct_in, in, dctn, qp->qpn);
-	MLX5_SET(destroy_dct_in, in, uid, qp->uid);
-	err = mlx5_cmd_exec(dev, (void *)&in, sizeof(in),
-			    (void *)&out, sizeof(out));
-	return err;
+	return _mlx5_core_destroy_dct(dev, dct, true);
 }
 EXPORT_SYMBOL_GPL(mlx5_core_destroy_dct);