Architectures that support memory tagging have a need to perform untagging (stripping the tag) in various parts of the kernel. This patch adds an untagged_addr() macro, which is defined as noop for architectures that do not support memory tagging. The oncoming patch series will define it at least for sparc64 and arm64. Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Reviewed-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> --- include/linux/mm.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index 0e8834ac32b7..dd0b5f4e1e45 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -99,6 +99,17 @@ extern int mmap_rnd_compat_bits __read_mostly; #include <asm/pgtable.h> #include <asm/processor.h> +/* + * Architectures that support memory tagging (assigning tags to memory regions, + * embedding these tags into addresses that point to these memory regions, and + * checking that the memory and the pointer tags match on memory accesses) + * redefine this macro to strip tags from pointers. + * It's defined as noop for arcitectures that don't support memory tagging. + */ +#ifndef untagged_addr +#define untagged_addr(addr) (addr) +#endif + #ifndef __pa_symbol #define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0)) #endif -- 2.22.0.rc1.311.g5d7573a151-goog
