From 23e94994464a7281838785675e09c8ed1055f62f Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 2 Jun 2015 15:18:38 +0100 Subject: arm64: lib: use pair accessors for copy_*_user routines The AArch64 instruction set contains load/store pair memory accessors, so use these in our copy_*_user routines to transfer 16 bytes per iteration. Reviewed-by: Catalin Marinas Signed-off-by: Will Deacon --- arch/arm64/lib/copy_in_user.S | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'arch/arm64/lib/copy_in_user.S') diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index 84b6c9bb9b93..436bcc5d77b5 100644 --- a/arch/arm64/lib/copy_in_user.S +++ b/arch/arm64/lib/copy_in_user.S @@ -30,14 +30,19 @@ * x0 - bytes not copied */ ENTRY(__copy_in_user) - add x4, x0, x2 // upper user buffer boundary - subs x2, x2, #8 + add x5, x0, x2 // upper user buffer boundary + subs x2, x2, #16 + b.mi 1f +0: +USER(9f, ldp x3, x4, [x1], #16) + subs x2, x2, #16 +USER(9f, stp x3, x4, [x0], #16) + b.pl 0b +1: adds x2, x2, #8 b.mi 2f -1: USER(9f, ldr x3, [x1], #8 ) - subs x2, x2, #8 + sub x2, x2, #8 USER(9f, str x3, [x0], #8 ) - b.pl 1b 2: adds x2, x2, #4 b.mi 3f USER(9f, ldr w3, [x1], #4 ) @@ -58,6 +63,6 @@ ENDPROC(__copy_in_user) .section .fixup,"ax" .align 2 -9: sub x0, x4, x0 // bytes not copied +9: sub x0, x5, x0 // bytes not copied ret .previous -- cgit v1.2.3