Revert "arm64: Avoid premature usercopy failure"

hulk inclusion
category: performance
bugzilla: https://e.gitee.com/open_euler/issues/list?issue=I4SCW7
CVE: NA

-------------------------------------------------------------------------

This reverts commit 8d4f091c.

Temporary rollback, which will be backported later so that other patches
can be backported without conflict.
Signed-off-by: NZhen Lei <thunder.leizhen@huawei.com>
Reviewed-by: NChen Wandun <chenwandun@huawei.com>
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm64/lib/copy_from_user.S

@@ -29,7 +29,7 @@
 	.endm
 
 	.macro ldrh1 reg, ptr, val
-	uao_user_alternative 9997f, ldrh, ldtrh, \reg, \ptr, \val
+	uao_user_alternative 9998f, ldrh, ldtrh, \reg, \ptr, \val
 	.endm
 
 	.macro strh1 reg, ptr, val
@@ -37,7 +37,7 @@
 	.endm
 
 	.macro ldr1 reg, ptr, val
-	uao_user_alternative 9997f, ldr, ldtr, \reg, \ptr, \val
+	uao_user_alternative 9998f, ldr, ldtr, \reg, \ptr, \val
 	.endm
 
 	.macro str1 reg, ptr, val
@@ -45,7 +45,7 @@
 	.endm
 
 	.macro ldp1 reg1, reg2, ptr, val
-	uao_ldp 9997f, \reg1, \reg2, \ptr, \val
+	uao_ldp 9998f, \reg1, \reg2, \ptr, \val
 	.endm
 
 	.macro stp1 reg1, reg2, ptr, val
@@ -53,10 +53,8 @@
 	.endm
 
 end	.req	x5
-srcin	.req	x15
 SYM_FUNC_START(__arch_copy_from_user)
 	add	end, x0, x2
-	mov	srcin, x1
 #include "copy_template.S"
 	mov	x0, #0				// Nothing to copy
 	ret
@@ -65,11 +63,6 @@ EXPORT_SYMBOL(__arch_copy_from_user)
 
 	.section .fixup,"ax"
 	.align	2
-9997:	cmp	dst, dstin
-	b.ne	9998f
-	// Before being absolutely sure we couldn't copy anything, try harder
-USER(9998f, ldtrb tmp1w, [srcin])
-	strb	tmp1w, [dst], #1
 9998:	sub	x0, end, dst			// bytes not copied
 	ret
 	.previous

arch/arm64/lib/copy_in_user.S

@@ -30,34 +30,33 @@
 	.endm
 
 	.macro ldrh1 reg, ptr, val
-	uao_user_alternative 9997f, ldrh, ldtrh, \reg, \ptr, \val
+	uao_user_alternative 9998f, ldrh, ldtrh, \reg, \ptr, \val
 	.endm
 
 	.macro strh1 reg, ptr, val
-	uao_user_alternative 9997f, strh, sttrh, \reg, \ptr, \val
+	uao_user_alternative 9998f, strh, sttrh, \reg, \ptr, \val
 	.endm
 
 	.macro ldr1 reg, ptr, val
-	uao_user_alternative 9997f, ldr, ldtr, \reg, \ptr, \val
+	uao_user_alternative 9998f, ldr, ldtr, \reg, \ptr, \val
 	.endm
 
 	.macro str1 reg, ptr, val
-	uao_user_alternative 9997f, str, sttr, \reg, \ptr, \val
+	uao_user_alternative 9998f, str, sttr, \reg, \ptr, \val
 	.endm
 
 	.macro ldp1 reg1, reg2, ptr, val
-	uao_ldp 9997f, \reg1, \reg2, \ptr, \val
+	uao_ldp 9998f, \reg1, \reg2, \ptr, \val
 	.endm
 
 	.macro stp1 reg1, reg2, ptr, val
-	uao_stp 9997f, \reg1, \reg2, \ptr, \val
+	uao_stp 9998f, \reg1, \reg2, \ptr, \val
 	.endm
 
 end	.req	x5
-srcin	.req	x15
+
 SYM_FUNC_START(__arch_copy_in_user)
 	add	end, x0, x2
-	mov	srcin, x1
 #include "copy_template.S"
 	mov	x0, #0
 	ret
@@ -66,12 +65,6 @@ EXPORT_SYMBOL(__arch_copy_in_user)
 
 	.section .fixup,"ax"
 	.align	2
-9997:	cmp	dst, dstin
-	b.ne	9998f
-	// Before being absolutely sure we couldn't copy anything, try harder
-USER(9998f, ldtrb tmp1w, [srcin])
-USER(9998f, sttrb tmp1w, [dst])
-	add	dst, dst, #1
 9998:	sub	x0, end, dst			// bytes not copied
 	ret
 	.previous

arch/arm64/lib/copy_to_user.S

@@ -32,7 +32,7 @@
 	.endm
 
 	.macro strh1 reg, ptr, val
-	uao_user_alternative 9997f, strh, sttrh, \reg, \ptr, \val
+	uao_user_alternative 9998f, strh, sttrh, \reg, \ptr, \val
 	.endm
 
 	.macro ldr1 reg, ptr, val
@@ -40,7 +40,7 @@
 	.endm
 
 	.macro str1 reg, ptr, val
-	uao_user_alternative 9997f, str, sttr, \reg, \ptr, \val
+	uao_user_alternative 9998f, str, sttr, \reg, \ptr, \val
 	.endm
 
 	.macro ldp1 reg1, reg2, ptr, val
@@ -48,14 +48,12 @@
 	.endm
 
 	.macro stp1 reg1, reg2, ptr, val
-	uao_stp 9997f, \reg1, \reg2, \ptr, \val
+	uao_stp 9998f, \reg1, \reg2, \ptr, \val
 	.endm
 
 end	.req	x5
-srcin	.req	x15
 SYM_FUNC_START(__arch_copy_to_user)
 	add	end, x0, x2
-	mov	srcin, x1
 #include "copy_template.S"
 	mov	x0, #0
 	ret
@@ -64,12 +62,6 @@ EXPORT_SYMBOL(__arch_copy_to_user)
 
 	.section .fixup,"ax"
 	.align	2
-9997:	cmp	dst, dstin
-	b.ne	9998f
-	// Before being absolutely sure we couldn't copy anything, try harder
-	ldrb	tmp1w, [srcin]
-USER(9998f, sttrb tmp1w, [dst])
-	add	dst, dst, #1
 9998:	sub	x0, end, dst			// bytes not copied
 	ret
 	.previous