[PATCH net-next 2/3] net/mlx4_core: Translate guest B0 steering rules to DMFS

[Amir Vadai <amirv@mellanox.com>]

From: Hadar Hen Zion <hadarh@mellanox.com>

The different steering modes are global to the device, with DMFS
being introduced after SRIOV was merged. Hence, SRIOV guests running
legacy / older Linux kernels or non-Linux drivers may provide
B0 steering directives when the hypervisor is using DMFS and fail.

Under B0 only L2 steering rules are allowed, hence B0 is a subset of DMFS.
Use this fact to enable such legacy guests to run by modifying the SRIOV
B0 steering wrapper to translate guest B0 directives to DMFS ones when
the device uses DMFS. The translated B0 rule has to be kept in the
resource tracker as a B0 object to allow for lookup in case of detach.

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
---
 .../net/ethernet/mellanox/mlx4/resource_tracker.c  |   85 +++++++++++++++-----
 1 files changed, 63 insertions(+), 22 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
index 1391b52..f2d6443 100644
--- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
+++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
@@ -75,6 +75,7 @@ struct res_gid {
 	u8			gid[16];
 	enum mlx4_protocol	prot;
 	enum mlx4_steer_type	steer;
+	u64			reg_id;
 };
 
 enum res_qp_states {
@@ -2934,7 +2935,7 @@ static struct res_gid *find_gid(struct mlx4_dev *dev, int slave,
 
 static int add_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 		       u8 *gid, enum mlx4_protocol prot,
-		       enum mlx4_steer_type steer)
+		       enum mlx4_steer_type steer, u64 reg_id)
 {
 	struct res_gid *res;
 	int err;
@@ -2951,6 +2952,7 @@ static int add_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 		memcpy(res->gid, gid, 16);
 		res->prot = prot;
 		res->steer = steer;
+		res->reg_id = reg_id;
 		list_add_tail(&res->list, &rqp->mcg_list);
 		err = 0;
 	}
@@ -2961,7 +2963,7 @@ static int add_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 
 static int rem_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 		       u8 *gid, enum mlx4_protocol prot,
-		       enum mlx4_steer_type steer)
+		       enum mlx4_steer_type steer, u64 *reg_id)
 {
 	struct res_gid *res;
 	int err;
@@ -2971,6 +2973,7 @@ static int rem_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 	if (!res || res->prot != prot || res->steer != steer)
 		err = -EINVAL;
 	else {
+		*reg_id = res->reg_id;
 		list_del(&res->list);
 		kfree(res);
 		err = 0;
@@ -2980,6 +2983,37 @@ static int rem_mcg_res(struct mlx4_dev *dev, int slave, struct res_qp *rqp,
 	return err;
 }
 
+static int qp_attach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16],
+		     int block_loopback, enum mlx4_protocol prot,
+		     enum mlx4_steer_type type, u64 *reg_id)
+{
+	switch (dev->caps.steering_mode) {
+	case MLX4_STEERING_MODE_DEVICE_MANAGED:
+		return mlx4_trans_to_dmfs_attach(dev, qp, gid, gid[5],
+						block_loopback, prot,
+						reg_id);
+	case MLX4_STEERING_MODE_B0:
+		return mlx4_qp_attach_common(dev, qp, gid,
+					    block_loopback, prot, type);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int qp_detach(struct mlx4_dev *dev, struct mlx4_qp *qp, u8 gid[16],
+		     enum mlx4_protocol prot, enum mlx4_steer_type type,
+		     u64 reg_id)
+{
+	switch (dev->caps.steering_mode) {
+	case MLX4_STEERING_MODE_DEVICE_MANAGED:
+		return mlx4_flow_detach(dev, reg_id);
+	case MLX4_STEERING_MODE_B0:
+		return mlx4_qp_detach_common(dev, qp, gid, prot, type);
+	default:
+		return -EINVAL;
+	}
+}
+
 int mlx4_QP_ATTACH_wrapper(struct mlx4_dev *dev, int slave,
 			       struct mlx4_vhcr *vhcr,
 			       struct mlx4_cmd_mailbox *inbox,
@@ -2992,14 +3026,12 @@ int mlx4_QP_ATTACH_wrapper(struct mlx4_dev *dev, int slave,
 	int err;
 	int qpn;
 	struct res_qp *rqp;
+	u64 reg_id = 0;
 	int attach = vhcr->op_modifier;
 	int block_loopback = vhcr->in_modifier >> 31;
 	u8 steer_type_mask = 2;
 	enum mlx4_steer_type type = (gid[7] & steer_type_mask) >> 1;
 
-	if (dev->caps.steering_mode != MLX4_STEERING_MODE_B0)
-		return -EINVAL;
-
 	qpn = vhcr->in_modifier & 0xffffff;
 	err = get_res(dev, slave, qpn, RES_QP, &rqp);
 	if (err)
@@ -3007,30 +3039,32 @@ int mlx4_QP_ATTACH_wrapper(struct mlx4_dev *dev, int slave,
 
 	qp.qpn = qpn;
 	if (attach) {
-		err = add_mcg_res(dev, slave, rqp, gid, prot, type);
-		if (err)
+		err = qp_attach(dev, &qp, gid, block_loopback, prot,
+				type, &reg_id);
+		if (err) {
+			pr_err("Fail to attach rule to qp 0x%x\n", qpn);
 			goto ex_put;
-
-		err = mlx4_qp_attach_common(dev, &qp, gid,
-					    block_loopback, prot, type);
+		}
+		err = add_mcg_res(dev, slave, rqp, gid, prot, type, reg_id);
 		if (err)
-			goto ex_rem;
+			goto ex_detach;
 	} else {
-		err = rem_mcg_res(dev, slave, rqp, gid, prot, type);
+		err = rem_mcg_res(dev, slave, rqp, gid, prot, type, &reg_id);
 		if (err)
 			goto ex_put;
-		err = mlx4_qp_detach_common(dev, &qp, gid, prot, type);
-	}
 
+		err = qp_detach(dev, &qp, gid, prot, type, reg_id);
+		if (err)
+			pr_err("Fail to detach rule from qp 0x%x reg_id = 0x%llx\n",
+			       qpn, reg_id);
+	}
 	put_res(dev, slave, qpn, RES_QP);
-	return 0;
+	return err;
 
-ex_rem:
-	/* ignore error return below, already in error */
-	(void) rem_mcg_res(dev, slave, rqp, gid, prot, type);
+ex_detach:
+	qp_detach(dev, &qp, gid, prot, type, reg_id);
 ex_put:
 	put_res(dev, slave, qpn, RES_QP);
-
 	return err;
 }
 
@@ -3266,9 +3300,16 @@ static void detach_qp(struct mlx4_dev *dev, int slave, struct res_qp *rqp)
 	struct mlx4_qp qp; /* dummy for calling attach/detach */
 
 	list_for_each_entry_safe(rgid, tmp, &rqp->mcg_list, list) {
-		qp.qpn = rqp->local_qpn;
-		(void) mlx4_qp_detach_common(dev, &qp, rgid->gid, rgid->prot,
-					     rgid->steer);
+		switch (dev->caps.steering_mode) {
+		case MLX4_STEERING_MODE_DEVICE_MANAGED:
+			mlx4_flow_detach(dev, rgid->reg_id);
+			break;
+		case MLX4_STEERING_MODE_B0:
+			qp.qpn = rqp->local_qpn;
+			(void) mlx4_qp_detach_common(dev, &qp, rgid->gid,
+						     rgid->prot, rgid->steer);
+			break;
+		}
 		list_del(&rgid->list);
 		kfree(rgid);
 	}
-- 
1.7.8.2