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| author | Andrey Konovalov <andreyknvl@google.com> | 2019-06-04 14:04:47 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-06-07 22:09:06 +0200 |
| commit | d93445225cd3c8eb0bf1350c04875576428b45b4 (patch) | |
| tree | 2fec9b8910f1883bd96986959ba3108cf67ea8fd | |
| parent | Merge tag 'xtensa-20190607' of git://github.com/jcmvbkbc/linux-xtensa (diff) | |
| download | linux-d93445225cd3c8eb0bf1350c04875576428b45b4.tar.xz linux-d93445225cd3c8eb0bf1350c04875576428b45b4.zip | |
uaccess: add noop untagged_addr definition
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@arm.com>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/mm.h | 11 |
1 files changed, 11 insertions, 0 deletions
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 |