net/mlx5: Add flow counter bulk infrastructure

Add infrastructure to track bulks of flow counters, providing
the means to allocate and deallocate bulks, and to acquire and
release individual counters from the bulks.
Signed-off-by: Gavi Teitz <gavi@mellanox.com>
Reviewed-by: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c

@@ -58,6 +58,7 @@ struct mlx5_fc {
 	u64 lastpackets;
 	u64 lastbytes;
 
+	struct mlx5_fc_bulk *bulk;
 	u32 id;
 	bool aging;
 
@@ -412,3 +413,107 @@ void mlx5_fc_update_sampling_interval(struct mlx5_core_dev *dev,
 	fc_stats->sampling_interval = min_t(unsigned long, interval,
 					    fc_stats->sampling_interval);
 }
+
+/* Flow counter bluks */
+
+struct mlx5_fc_bulk {
+	u32 base_id;
+	int bulk_len;
+	unsigned long *bitmask;
+	struct mlx5_fc fcs[0];
+};
+
+static void
+mlx5_fc_init(struct mlx5_fc *counter, struct mlx5_fc_bulk *bulk, u32 id)
+{
+	counter->bulk = bulk;
+	counter->id = id;
+}
+
+static int mlx5_fc_bulk_get_free_fcs_amount(struct mlx5_fc_bulk *bulk)
+{
+	return bitmap_weight(bulk->bitmask, bulk->bulk_len);
+}
+
+static struct mlx5_fc_bulk __attribute__((unused))
+*mlx5_fc_bulk_create(struct mlx5_core_dev *dev)
+{
+	enum mlx5_fc_bulk_alloc_bitmask alloc_bitmask;
+	struct mlx5_fc_bulk *bulk;
+	int err = -ENOMEM;
+	int bulk_len;
+	u32 base_id;
+	int i;
+
+	alloc_bitmask = MLX5_CAP_GEN(dev, flow_counter_bulk_alloc);
+	bulk_len = alloc_bitmask > 0 ? MLX5_FC_BULK_NUM_FCS(alloc_bitmask) : 1;
+
+	bulk = kzalloc(sizeof(*bulk) + bulk_len * sizeof(struct mlx5_fc),
+		       GFP_KERNEL);
+	if (!bulk)
+		goto err_alloc_bulk;
+
+	bulk->bitmask = kcalloc(BITS_TO_LONGS(bulk_len), sizeof(unsigned long),
+				GFP_KERNEL);
+	if (!bulk->bitmask)
+		goto err_alloc_bitmask;
+
+	err = mlx5_cmd_fc_bulk_alloc(dev, alloc_bitmask, &base_id);
+	if (err)
+		goto err_mlx5_cmd_bulk_alloc;
+
+	bulk->base_id = base_id;
+	bulk->bulk_len = bulk_len;
+	for (i = 0; i < bulk_len; i++) {
+		mlx5_fc_init(&bulk->fcs[i], bulk, base_id + i);
+		set_bit(i, bulk->bitmask);
+	}
+
+	return bulk;
+
+err_mlx5_cmd_bulk_alloc:
+	kfree(bulk->bitmask);
+err_alloc_bitmask:
+	kfree(bulk);
+err_alloc_bulk:
+	return ERR_PTR(err);
+}
+
+static int __attribute__((unused))
+mlx5_fc_bulk_destroy(struct mlx5_core_dev *dev, struct mlx5_fc_bulk *bulk)
+{
+	if (mlx5_fc_bulk_get_free_fcs_amount(bulk) < bulk->bulk_len) {
+		mlx5_core_err(dev, "Freeing bulk before all counters were released\n");
+		return -EBUSY;
+	}
+
+	mlx5_cmd_fc_free(dev, bulk->base_id);
+	kfree(bulk->bitmask);
+	kfree(bulk);
+
+	return 0;
+}
+
+static struct mlx5_fc __attribute__((unused))
+*mlx5_fc_bulk_acquire_fc(struct mlx5_fc_bulk *bulk)
+{
+	int free_fc_index = find_first_bit(bulk->bitmask, bulk->bulk_len);
+
+	if (free_fc_index >= bulk->bulk_len)
+		return ERR_PTR(-ENOSPC);
+
+	clear_bit(free_fc_index, bulk->bitmask);
+	return &bulk->fcs[free_fc_index];
+}
+
+static int __attribute__((unused))
+mlx5_fc_bulk_release_fc(struct mlx5_fc_bulk *bulk, struct mlx5_fc *fc)
+{
+	int fc_index = fc->id - bulk->base_id;
+
+	if (test_bit(fc_index, bulk->bitmask))
+		return -EINVAL;
+
+	set_bit(fc_index, bulk->bitmask);
+	return 0;
+}