Re: [PATCH net-next v9 2/3] net: ethernet: ti: Add desc_infos member to struct k3_cppi_desc_pool

[Jacob Keller <jacob.e.keller@intel.com>]

On 4/12/2024 8:38 AM, Julien Panis wrote:
> This patch introduces a member and the related accessors which can be
> used to store descriptor specific additional information. This member
> can store, for instance, an ID to differentiate a skb TX buffer type
> from a xdpf TX buffer type.
> 
> Signed-off-by: Julien Panis <jpanis@baylibre.com>
> ---
>  drivers/net/ethernet/ti/k3-cppi-desc-pool.c | 34 ++++++++++++++++++++++++-----
>  drivers/net/ethernet/ti/k3-cppi-desc-pool.h |  4 ++++
>  2 files changed, 33 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/ethernet/ti/k3-cppi-desc-pool.c b/drivers/net/ethernet/ti/k3-cppi-desc-pool.c
> index 414bcac9dcc6..739bae8e11ee 100644
> --- a/drivers/net/ethernet/ti/k3-cppi-desc-pool.c
> +++ b/drivers/net/ethernet/ti/k3-cppi-desc-pool.c
> @@ -22,6 +22,7 @@ struct k3_cppi_desc_pool {
>  	size_t			mem_size;
>  	size_t			num_desc;
>  	struct gen_pool		*gen_pool;
> +	void			**desc_infos;
>  };
>  
>  void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
> @@ -37,7 +38,11 @@ void k3_cppi_desc_pool_destroy(struct k3_cppi_desc_pool *pool)
>  		dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
>  				  pool->dma_addr);
>  
> +	kfree(pool->desc_infos);
> +
>  	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
> +
> +	kfree(pool);
>  }
>  EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_destroy);
>  
> @@ -50,7 +55,7 @@ k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
>  	const char *pool_name = NULL;
>  	int ret = -ENOMEM;
>  
> -	pool = devm_kzalloc(dev, sizeof(*pool), GFP_KERNEL);
> +	pool = kzalloc(sizeof(*pool), GFP_KERNEL);

You could refactor pool to use the new __free cleanup annotations along
with return_no_free() to automatically handle cleanup of the pool when
the function exits on an error state. It's pretty recent, and i don't
think its strictly necessary to do here just thought I'd point it out.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>

>  	if (!pool)
>  		return ERR_PTR(ret);
>  
> @@ -62,18 +67,21 @@ k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
>  	pool_name = kstrdup_const(name ? name : dev_name(pool->dev),
>  				  GFP_KERNEL);
>  	if (!pool_name)
> -		return ERR_PTR(-ENOMEM);
> +		goto gen_pool_create_fail;
>  
>  	pool->gen_pool = gen_pool_create(ilog2(pool->desc_size), -1);
>  	if (!pool->gen_pool) {
> -		ret = -ENOMEM;
> -		dev_err(pool->dev, "pool create failed %d\n", ret);
>  		kfree_const(pool_name);
>  		goto gen_pool_create_fail;
>  	}
>  
>  	pool->gen_pool->name = pool_name;
>  
> +	pool->desc_infos = kcalloc(pool->num_desc,
> +				   sizeof(*pool->desc_infos), GFP_KERNEL);
> +	if (!pool->desc_infos)
> +		goto gen_pool_desc_infos_alloc_fail;
> +
>  	pool->cpumem = dma_alloc_coherent(pool->dev, pool->mem_size,
>  					  &pool->dma_addr, GFP_KERNEL);
>  
> @@ -94,9 +102,11 @@ k3_cppi_desc_pool_create_name(struct device *dev, size_t size,
>  	dma_free_coherent(pool->dev, pool->mem_size, pool->cpumem,
>  			  pool->dma_addr);
>  dma_alloc_fail:
> +	kfree(pool->desc_infos);
> +gen_pool_desc_infos_alloc_fail:
>  	gen_pool_destroy(pool->gen_pool);	/* frees pool->name */
>  gen_pool_create_fail:
> -	devm_kfree(pool->dev, pool);
> +	kfree(pool);
>  	return ERR_PTR(ret);
>  }
>  EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_create_name);
> @@ -144,5 +154,19 @@ void *k3_cppi_desc_pool_cpuaddr(const struct k3_cppi_desc_pool *pool)
>  }
>  EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_cpuaddr);
>  
> +void k3_cppi_desc_pool_desc_info_set(struct k3_cppi_desc_pool *pool,
> +				     int desc_idx, void *info)
> +{
> +	pool->desc_infos[desc_idx] = info;
> +}
> +EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_desc_info_set);
> +
> +void *k3_cppi_desc_pool_desc_info(const struct k3_cppi_desc_pool *pool,
> +				  int desc_idx)
> +{
> +	return pool->desc_infos[desc_idx];
> +}
> +EXPORT_SYMBOL_GPL(k3_cppi_desc_pool_desc_info);
> +
>  MODULE_LICENSE("GPL");
>  MODULE_DESCRIPTION("TI K3 CPPI5 descriptors pool API");
> diff --git a/drivers/net/ethernet/ti/k3-cppi-desc-pool.h b/drivers/net/ethernet/ti/k3-cppi-desc-pool.h
> index 3c6aed0bed71..851d352b338b 100644
> --- a/drivers/net/ethernet/ti/k3-cppi-desc-pool.h
> +++ b/drivers/net/ethernet/ti/k3-cppi-desc-pool.h
> @@ -28,5 +28,9 @@ void k3_cppi_desc_pool_free(struct k3_cppi_desc_pool *pool, void *addr);
>  size_t k3_cppi_desc_pool_avail(struct k3_cppi_desc_pool *pool);
>  size_t k3_cppi_desc_pool_desc_size(const struct k3_cppi_desc_pool *pool);
>  void *k3_cppi_desc_pool_cpuaddr(const struct k3_cppi_desc_pool *pool);
> +void k3_cppi_desc_pool_desc_info_set(struct k3_cppi_desc_pool *pool,
> +				     int desc_idx, void *info);
> +void *k3_cppi_desc_pool_desc_info(const struct k3_cppi_desc_pool *pool,
> +				  int desc_idx);
>  
>  #endif /* K3_CPPI_DESC_POOL_H_ */
>