diff options
Diffstat (limited to 'arch/arm64/lib/clear_user.S')
| -rw-r--r-- | arch/arm64/lib/clear_user.S | 35 |
1 files changed, 25 insertions, 10 deletions
diff --git a/arch/arm64/lib/clear_user.S b/arch/arm64/lib/clear_user.S index a7efb2ad2a1c..de9a303b6ad0 100644 --- a/arch/arm64/lib/clear_user.S +++ b/arch/arm64/lib/clear_user.S @@ -4,7 +4,7 @@ */ #include <linux/linkage.h> -#include <asm/assembler.h> +#include <asm/asm-uaccess.h> .text @@ -17,14 +17,27 @@ * Alignment fixed up by hardware. */ - .p2align 4 - // Alignment is for the loop, but since the prologue (including BTI) - // is also 16 bytes we can keep any padding outside the function SYM_FUNC_START(__arch_clear_user) add x2, x0, x1 + +#ifdef CONFIG_AS_HAS_MOPS + .arch_extension mops +alternative_if_not ARM64_HAS_MOPS + b .Lno_mops +alternative_else_nop_endif + +USER(9f, setpt [x0]!, x1!, xzr) +USER(6f, setmt [x0]!, x1!, xzr) +USER(6f, setet [x0]!, x1!, xzr) + mov x0, #0 + ret +.Lno_mops: +#endif + subs x1, x1, #8 b.mi 2f -1: + +1: .p2align 4 USER(9f, sttr xzr, [x0]) add x0, x0, #8 subs x1, x1, #8 @@ -45,13 +58,15 @@ USER(9f, sttrh wzr, [x0]) USER(7f, sttrb wzr, [x2, #-1]) 5: mov x0, #0 ret -SYM_FUNC_END(__arch_clear_user) -EXPORT_SYMBOL(__arch_clear_user) - .section .fixup,"ax" - .align 2 + // Exception fixups +6: b.cs 9f + // Registers are in Option A format + add x0, x0, x1 + b 9f 7: sub x0, x2, #5 // Adjust for faulting on the final byte... 8: add x0, x0, #4 // ...or the second word of the 4-7 byte case 9: sub x0, x2, x0 ret - .previous +SYM_FUNC_END(__arch_clear_user) +EXPORT_SYMBOL(__arch_clear_user) |