Re: [PATCH 05/16] iommu/io-pgtable-arm-v7s: use page allocation function provided by iommu-pages.h

[Robin Murphy]

On 2023-11-28 8:49 pm, Pasha Tatashin wrote:
> Convert iommu/io-pgtable-arm-v7s.c to use the new page allocation functions
> provided in iommu-pages.h.
>
> Signed-off-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
> ---
>   drivers/iommu/io-pgtable-arm-v7s.c | 9 ++++++---
>   1 file changed, 6 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
> index 75f244a3e12d..3d494ca1f671 100644
> --- a/drivers/iommu/io-pgtable-arm-v7s.c
> +++ b/drivers/iommu/io-pgtable-arm-v7s.c
> @@ -34,6 +34,7 @@
>   #include <linux/types.h>
>   
>   #include <asm/barrier.h>
> +#include "iommu-pages.h"
>   
>   /* Struct accessors */
>   #define io_pgtable_to_data(x)						\
> @@ -255,7 +256,7 @@ static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
>   		 GFP_KERNEL : ARM_V7S_TABLE_GFP_DMA;
>   
>   	if (lvl == 1)
> -		table = (void *)__get_free_pages(gfp_l1 | __GFP_ZERO, get_order(size));
> +		table = iommu_alloc_pages(gfp_l1, get_order(size));
>   	else if (lvl == 2)
>   		table = kmem_cache_zalloc(data->l2_tables, gfp);

Is it really meaningful to account the L1 table which is always 
allocated upon initial creation, yet not the L2 tables which are 
allocated in use?

Thanks,
Robin.

> @@ -283,6 +284,7 @@ static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
>   	}
>   	if (lvl == 2)
>   		kmemleak_ignore(table);
> +
>   	return table;
>   
>   out_unmap:
> @@ -290,7 +292,7 @@ static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
>   	dma_unmap_single(dev, dma, size, DMA_TO_DEVICE);
>   out_free:
>   	if (lvl == 1)
> -		free_pages((unsigned long)table, get_order(size));
> +		iommu_free_pages(table, get_order(size));
>   	else
>   		kmem_cache_free(data->l2_tables, table);
>   	return NULL;
> @@ -306,8 +308,9 @@ static void __arm_v7s_free_table(void *table, int lvl,
>   	if (!cfg->coherent_walk)
>   		dma_unmap_single(dev, __arm_v7s_dma_addr(table), size,
>   				 DMA_TO_DEVICE);
> +
>   	if (lvl == 1)
> -		free_pages((unsigned long)table, get_order(size));
> +		iommu_free_pages(table, get_order(size));
>   	else
>   		kmem_cache_free(data->l2_tables, table);
>   }