Fixed MTP to work with TWRP

arch/cris/arch-v32/lib/csumcpfruser.S

@@ -0,0 +1,69 @@
+/*
+ * Add-on to transform csum_partial_copy_nocheck in checksumcopy.S into
+ * csum_partial_copy_from_user by adding exception records.
+ *
+ * Copyright (C) 2001, 2003 Axis Communications AB.
+ *
+ * Author: Hans-Peter Nilsson.
+ */
+
+#include <asm/errno.h>
+
+/* Same function body, but a different name.  If we just added exception
+   records to _csum_partial_copy_nocheck and made it generic, we wouldn't
+   know a user fault from a kernel fault and we would have overhead in
+   each kernel caller for the error-pointer argument.
+
+   unsigned int csum_partial_copy_from_user
+     (const char *src, char *dst, int len, unsigned int sum, int *errptr);
+
+   Note that the errptr argument is only set if we encounter an error.
+   It is conveniently located on the stack, so the normal function body
+   does not have to handle it.  */
+
+#define csum_partial_copy_nocheck csum_partial_copy_from_user
+
+/* There are local labels numbered 1, 2 and 3 present to mark the
+   different from-user accesses.  */
+#include "checksumcopy.S"
+
+	.section .fixup,"ax"
+
+;; Here from the movem loop; restore stack.
+4:
+	movem	[$sp+],$r8
+;; r12 is already decremented.  Add back chunk_size-2.
+	addq	40-2,$r12
+
+;; Here from the word loop; r12 is off by 2; add it back.
+5:
+	addq	2,$r12
+
+;; Here from a failing single byte.
+6:
+
+;; Signal in *errptr that we had a failing access.
+	move.d	[$sp],$acr
+	moveq	-EFAULT,$r9
+	subq	4,$sp
+	move.d	$r9,[$acr]
+
+;; Clear the rest of the destination area using memset.  Preserve the
+;; checksum for the readable bytes.
+	move.d	$r13,[$sp]
+	subq	4,$sp
+	move.d	$r11,$r10
+	move	$srp,[$sp]
+	jsr	memset
+	clear.d	$r11
+
+	move	[$sp+],$srp
+	ret
+	move.d	[$sp+],$r10
+
+	.previous
+	.section __ex_table,"a"
+	.dword 1b,4b
+	.dword 2b,5b
+	.dword 3b,6b
+	.previous