From: Arnd Bergmann <arnd@arndb.de>

When building with W=1, this variable is unused for configs with
CONFIG_CMA_SIZE_SEL_PERCENTAGE=y:

kernel/dma/contiguous.c:67:26: error: 'size_bytes' defined but not used [-Werror=unused-const-variable=]

Change this to a macro to avoid the warning.

Fixes: c64be2bb1c6e ("drivers: add Contiguous Memory Allocator")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
v4: fix type mistake from v3
v3: use a macro instead of constant
v2: fix spelling mistake.
---
 kernel/dma/contiguous.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 055da410ac71..8df0dfaaca18 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -64,8 +64,7 @@ struct cma *dma_contiguous_default_area;
  * Users, who want to set the size of global CMA area for their system
  * should use cma= kernel parameter.
  */
-static const phys_addr_t size_bytes __initconst =
-	(phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
+#define size_bytes ((phys_addr_t)CMA_SIZE_MBYTES * SZ_1M)
 static phys_addr_t  size_cmdline __initdata = -1;
 static phys_addr_t base_cmdline __initdata;
 static phys_addr_t limit_cmdline __initdata;
-- 
2.39.5

On 09.04.2025 17:15, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> When building with W=1, this variable is unused for configs with
> CONFIG_CMA_SIZE_SEL_PERCENTAGE=y:
>
> kernel/dma/contiguous.c:67:26: error: 'size_bytes' defined but not used [-Werror=unused-const-variable=]
>
> Change this to a macro to avoid the warning.
>
> Fixes: c64be2bb1c6e ("drivers: add Contiguous Memory Allocator")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>


Thanks, applied to dma-mapping-fixes branch.


> ---
> v4: fix type mistake from v3
> v3: use a macro instead of constant
> v2: fix spelling mistake.
> ---
>   kernel/dma/contiguous.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
> index 055da410ac71..8df0dfaaca18 100644
> --- a/kernel/dma/contiguous.c
> +++ b/kernel/dma/contiguous.c
> @@ -64,8 +64,7 @@ struct cma *dma_contiguous_default_area;
>    * Users, who want to set the size of global CMA area for their system
>    * should use cma= kernel parameter.
>    */
> -static const phys_addr_t size_bytes __initconst =
> -	(phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
> +#define size_bytes ((phys_addr_t)CMA_SIZE_MBYTES * SZ_1M)
>   static phys_addr_t  size_cmdline __initdata = -1;
>   static phys_addr_t base_cmdline __initdata;
>   static phys_addr_t limit_cmdline __initdata;

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland