net/mlx5e: Get or put meter by the index of tc police action

Add functions to create and destroy flow meter aso object.
This object only supports the range allocation. 64 objects are
allocated at a time, and there are two meters in each object.
Usually only one meter is allocated for a flow, so bitmap is used
to manage these 128 meters.

TC police action is mapped to hardware meter. As the index is unique
for each police action, add APIs to allocate or free hardware meter by
the index. If the meter is already created, increment its refcnt,
otherwise create new one. If police action has different parameters,
update hardware meter accordingly.
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/en/tc/meter.c

@@ -4,6 +4,7 @@
 #include "lib/aso.h"
 #include "en/tc/post_act.h"
 #include "meter.h"
+#include "en/tc_priv.h"
 
 #define MLX5_START_COLOR_SHIFT 28
 #define MLX5_METER_MODE_SHIFT 24
@@ -21,6 +22,14 @@
 #define MLX5_MAX_CBS ((0x100ULL << 0x1F) - 1)
 #define MLX5_MAX_HW_CBS 0x7FFFFFFF
 
+struct mlx5e_flow_meter_aso_obj {
+	struct list_head entry;
+	int base_id;
+	int total_meters;
+
+	unsigned long meters_map[0]; /* must be at the end of this struct */
+};
+
 struct mlx5e_flow_meters {
 	enum mlx5_flow_namespace_type ns_type;
 	struct mlx5_aso *aso;
@@ -28,6 +37,12 @@ struct mlx5e_flow_meters {
 	int log_granularity;
 	u32 pdn;
 
+	DECLARE_HASHTABLE(hashtbl, 8);
+
+	struct mutex sync_lock; /* protect flow meter operations */
+	struct list_head partial_list;
+	struct list_head full_list;
+
 	struct mlx5_core_dev *mdev;
 	struct mlx5e_post_act *post_act;
 };
@@ -177,6 +192,200 @@ mlx5e_tc_meter_modify(struct mlx5_core_dev *mdev,
 	return err;
 }
 
+static int
+mlx5e_flow_meter_create_aso_obj(struct mlx5e_flow_meters *flow_meters, int *obj_id)
+{
+	u32 in[MLX5_ST_SZ_DW(create_flow_meter_aso_obj_in)] = {};
+	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)];
+	struct mlx5_core_dev *mdev = flow_meters->mdev;
+	void *obj;
+	int err;
+
+	MLX5_SET(general_obj_in_cmd_hdr, in, opcode, MLX5_CMD_OP_CREATE_GENERAL_OBJECT);
+	MLX5_SET(general_obj_in_cmd_hdr, in, obj_type,
+		 MLX5_GENERAL_OBJECT_TYPES_FLOW_METER_ASO);
+	MLX5_SET(general_obj_in_cmd_hdr, in, log_obj_range, flow_meters->log_granularity);
+
+	obj = MLX5_ADDR_OF(create_flow_meter_aso_obj_in, in, flow_meter_aso_obj);
+	MLX5_SET(flow_meter_aso_obj, obj, meter_aso_access_pd, flow_meters->pdn);
+
+	err = mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
+	if (!err) {
+		*obj_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);
+		mlx5_core_dbg(mdev, "flow meter aso obj(0x%x) created\n", *obj_id);
+	}
+
+	return err;
+}
+
+static void
+mlx5e_flow_meter_destroy_aso_obj(struct mlx5_core_dev *mdev, u32 obj_id)
+{
+	u32 in[MLX5_ST_SZ_DW(general_obj_in_cmd_hdr)] = {};
+	u32 out[MLX5_ST_SZ_DW(general_obj_out_cmd_hdr)];
+
+	MLX5_SET(general_obj_in_cmd_hdr, in, opcode, MLX5_CMD_OP_DESTROY_GENERAL_OBJECT);
+	MLX5_SET(general_obj_in_cmd_hdr, in, obj_type,
+		 MLX5_GENERAL_OBJECT_TYPES_FLOW_METER_ASO);
+	MLX5_SET(general_obj_in_cmd_hdr, in, obj_id, obj_id);
+
+	mlx5_cmd_exec(mdev, in, sizeof(in), out, sizeof(out));
+	mlx5_core_dbg(mdev, "flow meter aso obj(0x%x) destroyed\n", obj_id);
+}
+
+static struct mlx5e_flow_meter_handle *
+__mlx5e_flow_meter_alloc(struct mlx5e_flow_meters *flow_meters)
+{
+	struct mlx5_core_dev *mdev = flow_meters->mdev;
+	struct mlx5e_flow_meter_aso_obj *meters_obj;
+	struct mlx5e_flow_meter_handle *meter;
+	int err, pos, total;
+	u32 id;
+
+	meter = kzalloc(sizeof(*meter), GFP_KERNEL);
+	if (!meter)
+		return ERR_PTR(-ENOMEM);
+
+	meters_obj = list_first_entry_or_null(&flow_meters->partial_list,
+					      struct mlx5e_flow_meter_aso_obj,
+					      entry);
+	/* 2 meters in one object */
+	total = 1 << (flow_meters->log_granularity + 1);
+	if (!meters_obj) {
+		err = mlx5e_flow_meter_create_aso_obj(flow_meters, &id);
+		if (err) {
+			mlx5_core_err(mdev, "Failed to create flow meter ASO object\n");
+			goto err_create;
+		}
+
+		meters_obj = kzalloc(sizeof(*meters_obj) + BITS_TO_BYTES(total),
+				     GFP_KERNEL);
+		if (!meters_obj) {
+			err = -ENOMEM;
+			goto err_mem;
+		}
+
+		meters_obj->base_id = id;
+		meters_obj->total_meters = total;
+		list_add(&meters_obj->entry, &flow_meters->partial_list);
+		pos = 0;
+	} else {
+		pos = find_first_zero_bit(meters_obj->meters_map, total);
+		if (bitmap_weight(meters_obj->meters_map, total) == total - 1) {
+			list_del(&meters_obj->entry);
+			list_add(&meters_obj->entry, &flow_meters->full_list);
+		}
+	}
+
+	bitmap_set(meters_obj->meters_map, pos, 1);
+	meter->flow_meters = flow_meters;
+	meter->meters_obj = meters_obj;
+	meter->obj_id = meters_obj->base_id + pos / 2;
+	meter->idx = pos % 2;
+
+	mlx5_core_dbg(mdev, "flow meter allocated, obj_id=0x%x, index=%d\n",
+		      meter->obj_id, meter->idx);
+
+	return meter;
+
+err_mem:
+	mlx5e_flow_meter_destroy_aso_obj(mdev, id);
+err_create:
+	kfree(meter);
+	return ERR_PTR(err);
+}
+
+static void
+__mlx5e_flow_meter_free(struct mlx5e_flow_meter_handle *meter)
+{
+	struct mlx5e_flow_meters *flow_meters = meter->flow_meters;
+	struct mlx5_core_dev *mdev = flow_meters->mdev;
+	struct mlx5e_flow_meter_aso_obj *meters_obj;
+	int n, pos;
+
+	meters_obj = meter->meters_obj;
+	pos = (meter->obj_id - meters_obj->base_id) * 2 + meter->idx;
+	bitmap_clear(meters_obj->meters_map, pos, 1);
+	n = bitmap_weight(meters_obj->meters_map, meters_obj->total_meters);
+	if (n == 0) {
+		list_del(&meters_obj->entry);
+		mlx5e_flow_meter_destroy_aso_obj(mdev, meters_obj->base_id);
+		kfree(meters_obj);
+	} else if (n == meters_obj->total_meters - 1) {
+		list_del(&meters_obj->entry);
+		list_add(&meters_obj->entry, &flow_meters->partial_list);
+	}
+
+	mlx5_core_dbg(mdev, "flow meter freed, obj_id=0x%x, index=%d\n",
+		      meter->obj_id, meter->idx);
+	kfree(meter);
+}
+
+struct mlx5e_flow_meter_handle *
+mlx5e_tc_meter_get(struct mlx5_core_dev *mdev, struct mlx5e_flow_meter_params *params)
+{
+	struct mlx5e_flow_meters *flow_meters;
+	struct mlx5e_flow_meter_handle *meter;
+	int err;
+
+	flow_meters = mlx5e_get_flow_meters(mdev);
+	if (!flow_meters)
+		return ERR_PTR(-EOPNOTSUPP);
+
+	mutex_lock(&flow_meters->sync_lock);
+	hash_for_each_possible(flow_meters->hashtbl, meter, hlist, params->index)
+		if (meter->params.index == params->index)
+			goto add_ref;
+
+	meter = __mlx5e_flow_meter_alloc(flow_meters);
+	if (IS_ERR(meter)) {
+		err = PTR_ERR(meter);
+		goto err_alloc;
+	}
+
+	hash_add(flow_meters->hashtbl, &meter->hlist, params->index);
+	meter->params.index = params->index;
+
+add_ref:
+	meter->refcnt++;
+
+	if (meter->params.mode != params->mode || meter->params.rate != params->rate ||
+	    meter->params.burst != params->burst) {
+		err = mlx5e_tc_meter_modify(mdev, meter, params);
+		if (err)
+			goto err_update;
+
+		meter->params.mode = params->mode;
+		meter->params.rate = params->rate;
+		meter->params.burst = params->burst;
+	}
+
+	mutex_unlock(&flow_meters->sync_lock);
+	return meter;
+
+err_update:
+	if (--meter->refcnt == 0) {
+		hash_del(&meter->hlist);
+		__mlx5e_flow_meter_free(meter);
+	}
+err_alloc:
+	mutex_unlock(&flow_meters->sync_lock);
+	return ERR_PTR(err);
+}
+
+void
+mlx5e_tc_meter_put(struct mlx5e_flow_meter_handle *meter)
+{
+	struct mlx5e_flow_meters *flow_meters = meter->flow_meters;
+
+	mutex_lock(&flow_meters->sync_lock);
+	if (--meter->refcnt == 0) {
+		hash_del(&meter->hlist);
+		__mlx5e_flow_meter_free(meter);
+	}
+	mutex_unlock(&flow_meters->sync_lock);
+}
+
 struct mlx5e_flow_meters *
 mlx5e_flow_meters_init(struct mlx5e_priv *priv,
 		       enum mlx5_flow_namespace_type ns_type,
@@ -213,6 +422,10 @@ mlx5e_flow_meters_init(struct mlx5e_priv *priv,
 		goto err_sq;
 	}
 
+	mutex_init(&flow_meters->sync_lock);
+	INIT_LIST_HEAD(&flow_meters->partial_list);
+	INIT_LIST_HEAD(&flow_meters->full_list);
+
 	flow_meters->ns_type = ns_type;
 	flow_meters->mdev = mdev;
 	flow_meters->post_act = post_act;

drivers/net/ethernet/mellanox/mlx5/core/en/tc/meter.h

@@ -4,6 +4,7 @@
 #ifndef __MLX5_EN_FLOW_METER_H__
 #define __MLX5_EN_FLOW_METER_H__
 
+struct mlx5e_flow_meter_aso_obj;
 struct mlx5e_flow_meters;
 
 enum mlx5e_flow_meter_mode {
@@ -13,14 +14,21 @@ enum mlx5e_flow_meter_mode {
 
 struct mlx5e_flow_meter_params {
 	enum mlx5e_flow_meter_mode mode;
+	 /* police action index */
+	u32 index;
 	u64 rate;
 	u64 burst;
 };
 
 struct mlx5e_flow_meter_handle {
 	struct mlx5e_flow_meters *flow_meters;
+	struct mlx5e_flow_meter_aso_obj *meters_obj;
 	u32 obj_id;
 	u8 idx;
+
+	int refcnt;
+	struct hlist_node hlist;
+	struct mlx5e_flow_meter_params params;
 };
 
 int
@@ -28,6 +36,11 @@ mlx5e_tc_meter_modify(struct mlx5_core_dev *mdev,
 		      struct mlx5e_flow_meter_handle *meter,
 		      struct mlx5e_flow_meter_params *meter_params);
 
+struct mlx5e_flow_meter_handle *
+mlx5e_tc_meter_get(struct mlx5_core_dev *mdev, struct mlx5e_flow_meter_params *params);
+void
+mlx5e_tc_meter_put(struct mlx5e_flow_meter_handle *meter);
+
 struct mlx5e_flow_meters *
 mlx5e_flow_meters_init(struct mlx5e_priv *priv,
 		       enum mlx5_flow_namespace_type ns_type,