diff options
Diffstat (limited to 'arch/arm64/lib/copy_from_user.S')
-rw-r--r-- | arch/arm64/lib/copy_from_user.S | 78 |
1 files changed, 44 insertions, 34 deletions
diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S index 1be9ef27be97..4699cd74f87e 100644 --- a/arch/arm64/lib/copy_from_user.S +++ b/arch/arm64/lib/copy_from_user.S @@ -18,6 +18,7 @@ #include <asm/alternative.h> #include <asm/assembler.h> +#include <asm/cache.h> #include <asm/cpufeature.h> #include <asm/sysreg.h> @@ -31,49 +32,58 @@ * Returns: * x0 - bytes not copied */ + + .macro ldrb1 ptr, regB, val + USER(9998f, ldrb \ptr, [\regB], \val) + .endm + + .macro strb1 ptr, regB, val + strb \ptr, [\regB], \val + .endm + + .macro ldrh1 ptr, regB, val + USER(9998f, ldrh \ptr, [\regB], \val) + .endm + + .macro strh1 ptr, regB, val + strh \ptr, [\regB], \val + .endm + + .macro ldr1 ptr, regB, val + USER(9998f, ldr \ptr, [\regB], \val) + .endm + + .macro str1 ptr, regB, val + str \ptr, [\regB], \val + .endm + + .macro ldp1 ptr, regB, regC, val + USER(9998f, ldp \ptr, \regB, [\regC], \val) + .endm + + .macro stp1 ptr, regB, regC, val + stp \ptr, \regB, [\regC], \val + .endm + +end .req x5 ENTRY(__copy_from_user) ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(0)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) - 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 -USER(9f, ldr x3, [x1], #8 ) - sub x2, x2, #8 - str x3, [x0], #8 -2: adds x2, x2, #4 - b.mi 3f -USER(9f, ldr w3, [x1], #4 ) - sub x2, x2, #4 - str w3, [x0], #4 -3: adds x2, x2, #2 - b.mi 4f -USER(9f, ldrh w3, [x1], #2 ) - sub x2, x2, #2 - strh w3, [x0], #2 -4: adds x2, x2, #1 - b.mi 5f -USER(9f, ldrb w3, [x1] ) - strb w3, [x0] -5: mov x0, #0 + add end, x0, x2 +#include "copy_template.S" ALTERNATIVE("nop", __stringify(SET_PSTATE_PAN(1)), ARM64_HAS_PAN, \ CONFIG_ARM64_PAN) + mov x0, #0 // Nothing to copy ret ENDPROC(__copy_from_user) .section .fixup,"ax" .align 2 -9: sub x2, x5, x1 - mov x3, x2 -10: strb wzr, [x0], #1 // zero remaining buffer space - subs x3, x3, #1 - b.ne 10b - mov x0, x2 // bytes not copied +9998: + sub x0, end, dst +9999: + strb wzr, [dst], #1 // zero remaining buffer space + cmp dst, end + b.lo 9999b ret .previous |