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authorGeoff Levand <geoff@infradead.org>2016-04-27 17:47:10 +0100
committerSami Tolvanen <samitolvanen@google.com>2016-09-29 10:52:56 -0700
commit9887915a4ecf3697d056f01f8e7fe09c853f93bb (patch)
tree5a71c9320f78210ffed71db6bef1d93db195bdcb
parentb8f39d900e1581dd99788c1e38989b93d114dced (diff)
UPSTREAM: 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> Change-Id: If23a454e211b1f57f8ba1a2a00b44dabf4b82932 (cherry picked from commit 5003dbde45961dd7ab3d8a09ab9ad8bcb604db40) Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
-rw-r--r--arch/arm64/include/asm/assembler.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 33bbb7ba7fb5..290e13428f4a 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>
@@ -292,6 +293,24 @@ 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.
*/