From: Will Deacon will.deacon@arm.com
commit 23e94994464a7281838785675e09c8ed1055f62f upstream.
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 catalin.marinas@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: David Brown david.brown@linaro.org --- arch/arm64/lib/copy_from_user.S | 17 +++++++++++------ arch/arm64/lib/copy_in_user.S | 17 +++++++++++------ arch/arm64/lib/copy_to_user.S | 17 +++++++++++------ 3 files changed, 33 insertions(+), 18 deletions(-)
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 5e27add..47c3fa5 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -28,14 +28,19 @@ * x0 - bytes not copied */ ENTRY(__copy_from_user) - add x4, x1, x2 // upper user buffer boundary - subs x2, x2, #8 + add x5, x1, x2 // upper user buffer boundary + subs x2, x2, #16 + b.mi 1f +0: +USER(9f, ldp x3, x4, [x1], #16) + subs x2, x2, #16 + 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 str x3, [x0], #8 - b.pl 1b 2: adds x2, x2, #4 b.mi 3f USER(9f, ldr w3, [x1], #4 ) @@ -56,7 +61,7 @@ ENDPROC(__copy_from_user)
.section .fixup,"ax" .align 2 -9: sub x2, x4, x1 +9: sub x2, x5, x1 mov x3, x2 10: strb wzr, [x0], #1 // zero remaining buffer space subs x3, x3, #1 diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S index 84b6c9b..436bcc5 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 diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S index a0aeeb9..f5e1f52 100644 --- a/arch/arm64/lib/copy_to_user.S +++ b/arch/arm64/lib/copy_to_user.S @@ -28,14 +28,19 @@ * x0 - bytes not copied */ ENTRY(__copy_to_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: + 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: 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 ldr w3, [x1], #4 @@ -56,6 +61,6 @@ ENDPROC(__copy_to_user)
.section .fixup,"ax" .align 2 -9: sub x0, x4, x0 // bytes not copied +9: sub x0, x5, x0 // bytes not copied ret .previous