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author | Geoff Levand <geoff@infradead.org> | 2016-04-27 17:47:10 +0100 |
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committer | Will Deacon <will.deacon@arm.com> | 2016-04-28 12:05:46 +0100 |
commit | 5003dbde45961dd7ab3d8a09ab9ad8bcb604db40 (patch) | |
tree | 84847e1eb60d698038a9fb900e8fbf0dfccbfd3c /arch/arm64 | |
parent | 28c7258330ee4ce701a4da7af96d6605d1a0b3bd (diff) | |
download | linux-5003dbde45961dd7ab3d8a09ab9ad8bcb604db40.tar.bz2 |
arm64: Add new asm macro copy_page
Kexec and hibernate need to copy pages of memory, but may not have all
of the kernel mapped, and are unable to call copy_page().
Add a simplistic copy_page() macro, that can be inlined in these
situations. lib/copy_page.S provides a bigger better version, but
uses more registers.
Signed-off-by: Geoff Levand <geoff@infradead.org>
[Changed asm label to 9998, added commit message]
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/include/asm/assembler.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 3b3812a3e8b9..10b017c4bdd8 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -24,6 +24,7 @@ #define __ASM_ASSEMBLER_H #include <asm/asm-offsets.h> +#include <asm/page.h> #include <asm/pgtable-hwdef.h> #include <asm/ptrace.h> #include <asm/thread_info.h> @@ -280,6 +281,24 @@ lr .req x30 // link register .endm /* + * copy_page - copy src to dest using temp registers t1-t8 + */ + .macro copy_page dest:req src:req t1:req t2:req t3:req t4:req t5:req t6:req t7:req t8:req +9998: ldp \t1, \t2, [\src] + ldp \t3, \t4, [\src, #16] + ldp \t5, \t6, [\src, #32] + ldp \t7, \t8, [\src, #48] + add \src, \src, #64 + stnp \t1, \t2, [\dest] + stnp \t3, \t4, [\dest, #16] + stnp \t5, \t6, [\dest, #32] + stnp \t7, \t8, [\dest, #48] + add \dest, \dest, #64 + tst \src, #(PAGE_SIZE - 1) + b.ne 9998b + .endm + +/* * Annotate a function as position independent, i.e., safe to be called before * the kernel virtual mapping is activated. */ |