patch-2.1.4 linux/arch/alpha/lib/get_user.S

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diff -u --recursive --new-file v2.1.3/linux/arch/alpha/lib/get_user.S linux/arch/alpha/lib/get_user.S
@@ -0,0 +1,98 @@
+/*
+ * arch/alpha/lib/get_user.S
+ *
+ * (C) Copyright 1996 Linus Torvalds
+ */
+
+/*
+ * This does simple reads from user mode, returning zero for
+ * success and -EINVAL for a fault. Note that we may NOT do
+ * unaligned accesses, because the unaligned fault handler
+ * must not take the exception..
+ *
+ * NOTE! These are NOT normal function calls callable from C.
+ * As we have two return values (the actual value gotten from
+ * user space, and the error return value) the calling sequence
+ * is different.
+ *
+ * Input:
+ *	user address in $2
+ *	exception structure address in $3
+ *	return address in $28 (exceptions expect it there)
+ *
+ * Output:
+ *	error number in $0
+ *	actual result in $1
+ *
+ * Clobbers:
+ *	$4,$5
+ */
+	.set noat
+	.align 3
+	.globl __get_user_8
+	.ent __get_user_8
+__get_user_8:
+	ldq $4,0($3)
+	lda $0,-14
+	addq $4,1,$5
+	stq $5,0($3)
+	ldq_u $1,0($2)
+	stq $4,0($3)
+	bis $31,$31,$0
+	extbl $1,$2,$1
+	ret $31,($28),1
+	.end __get_user_8
+
+	.align 3
+	.globl __get_user_16
+	.ent __get_user_16
+__get_user_16:
+	ldq $4,0($3)
+	lda $0,-14
+	addq $4,1,$5
+	stq $5,0($3)
+	ldq_u $1,0($2)
+	ldq_u $5,1($2)
+	stq $4,0($3)
+	extwl $1,$2,$1
+	bis $31,$31,$0
+	extwh $5,$2,$5
+	bis $1,$5,$1
+	ret $31,($28),1
+	.end __get_user_16
+
+	.align 3
+	.globl __get_user_32
+	.ent __get_user_32
+__get_user_32:
+	ldq $4,0($3)
+	lda $0,-14
+	addq $4,1,$5
+	stq $5,0($3)
+	ldq_u $1,0($2)
+	ldq_u $5,3($2)
+	stq $4,0($3)
+	extll $1,$2,$1
+	bis $31,$31,$0
+	extlh $5,$2,$5
+	bis $1,$5,$1
+	ret $31,($28),1
+	.end __get_user_32
+
+	.align 3
+	.globl __get_user_64
+	.ent __get_user_64
+__get_user_64:
+	ldq $4,0($3)
+	lda $0,-14
+	addq $4,1,$5
+	stq $5,0($3)
+	ldq_u $1,0($2)
+	ldq_u $5,7($2)
+	stq $4,0($3)
+	extql $1,$2,$1
+	bis $31,$31,$0
+	extqh $5,$2,$5
+	bis $1,$5,$1
+	ret $31,($28),1
+	.end __get_user_64

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