dma/contiguous: avoid warning about unused size_bytes

commit d7b98ae
Author: Arnd Bergmann <[email protected]>
Date: Wed Apr 9 17:15:42 2025 +0200

    dma/contiguous: avoid warning about unused size_bytes

    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: c64be2b ("drivers: add Contiguous Memory Allocator")
    Signed-off-by: Arnd Bergmann <[email protected]>
    Signed-off-by: Marek Szyprowski <[email protected]>
    Link: https://lore.kernel.org/r/[email protected]

(cherry picked from commit d7b98ae)
Signed-off-by: Jerry Snitselaar <[email protected]>
Upstream-Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
JIRA: https://issues.redhat.com/browse/RHEL-89891

Author: snits

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;