aboutsummaryrefslogtreecommitdiff
path: root/arch/arm64/lib/copy_from_user.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/lib/copy_from_user.S')
-rw-r--r--arch/arm64/lib/copy_from_user.S78
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