Re: [PATCH net-next v4 12/15] net: macb: introduce macb_context_alloc() helper

[Nicolai Buchwitz <nb@tipi-net.de>]

Hi Théo

On 17.7.2026 21:48, Théo Lebrun wrote:
> Move the context allocation sequence from inline macb_open() to its own
> helper function called macb_context_alloc(). All ops doing context
> swapping (set_ringparam, change_mtu, etc) will use this helper.
> 
> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> ---
>  drivers/net/ethernet/cadence/macb_main.c | 56 
> +++++++++++++++++++++-----------
>  1 file changed, 37 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/net/ethernet/cadence/macb_main.c 
> b/drivers/net/ethernet/cadence/macb_main.c
> index d396a307310b..4c94c23d925a 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -2866,6 +2866,36 @@ static int macb_alloc(struct macb_context *ctx)
>  	return -ENOMEM;
>  }
> 
> +static struct macb_context *macb_context_alloc(struct macb *bp,
> +					       unsigned int mtu,
> +					       unsigned int rx_ring_size,
> +					       unsigned int tx_ring_size)
> +{
> +	struct macb_context *ctx;
> +	int err;
> +
> +	ctx = kzalloc_obj(*ctx);
> +	if (!ctx)
> +		return ERR_PTR(-ENOMEM);
> +
> +	ctx->info = &bp->info;
> +	ctx->rx_buffer_size = macb_rx_buffer_size(bp, mtu);
> +	ctx->rx_ring_size = rx_ring_size;
> +	ctx->tx_ring_size = tx_ring_size;
> +
> +	err = macb_alloc(ctx);
> +	if (err) {
> +		netdev_err(bp->netdev,
> +			   "Unable to allocate DMA memory (error %d)\n", err);
> +		kfree(ctx);
> +		return ERR_PTR(err);
> +	}
> +
> +	bp->macbgem_ops.mog_init_rings(ctx);
> +
> +	return ctx;
> +}
> +
>  static void gem_init_rx_ring(struct macb_context *ctx, unsigned int q)
>  {
>  	struct macb_rxq *rxq = &ctx->rxq[q];
> @@ -3233,27 +3263,15 @@ static int macb_open(struct net_device *netdev)
>  	if (err < 0)
>  		return err;
> 
> -	bp->ctx = kzalloc_obj(*bp->ctx);
> -	if (!bp->ctx) {
> -		err = -ENOMEM;
> +	bp->ctx = macb_context_alloc(bp, netdev->mtu,
> +				     bp->configured_rx_ring_size,
> +				     bp->configured_tx_ring_size);
> +	if (IS_ERR(bp->ctx)) {
> +		err = PTR_ERR(bp->ctx);
> +		bp->ctx = NULL;
>  		goto pm_exit;
>  	}
> 
> -	bp->ctx->info = &bp->info;
> -
> -	/* RX buffers initialization */
> -	bp->ctx->rx_buffer_size = macb_rx_buffer_size(bp, netdev->mtu);
> -	bp->ctx->rx_ring_size = bp->configured_rx_ring_size;
> -	bp->ctx->tx_ring_size = bp->configured_tx_ring_size;
> -
> -	err = macb_alloc(bp->ctx);
> -	if (err) {
> -		netdev_err(netdev, "Unable to allocate DMA memory (error %d)\n",
> -			   err);
> -		goto free_ctx;
> -	}
> -
> -	bp->macbgem_ops.mog_init_rings(bp->ctx);
>  	macb_init_buffers(bp);
> 
>  	for (q = 0, queue = bp->queues; q < bp->num_queues; ++q, ++queue) {
> @@ -3292,7 +3310,6 @@ static int macb_open(struct net_device *netdev)
>  		napi_disable(&queue->napi_tx);
>  	}
>  	macb_free(bp->ctx);
> -free_ctx:
>  	kfree(bp->ctx);
>  	bp->ctx = NULL;
>  pm_exit:
> @@ -5175,6 +5192,7 @@ static int at91ether_open(struct net_device 
> *netdev)
>  		ret = -ENOMEM;
>  		goto pm_exit;
>  	}
> +	bp->ctx->info = &bp->info;
> 
>  	/* Clear internal statistics */
>  	ctl = macb_readl(bp, NCR);

Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>

Thanks
Nicolai