From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- arch/arm/lib/csumpartialcopyuser.S | 83 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 83 insertions(+) create mode 100644 arch/arm/lib/csumpartialcopyuser.S (limited to 'arch/arm/lib/csumpartialcopyuser.S') diff --git a/arch/arm/lib/csumpartialcopyuser.S b/arch/arm/lib/csumpartialcopyuser.S new file mode 100644 index 00000000..7d08b43d --- /dev/null +++ b/arch/arm/lib/csumpartialcopyuser.S @@ -0,0 +1,83 @@ +/* + * linux/arch/arm/lib/csumpartialcopyuser.S + * + * Copyright (C) 1995-1998 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 27/03/03 Ian Molton Clean up CONFIG_CPU + * + */ +#include +#include +#include +#include + + .text + + .macro save_regs + stmfd sp!, {r1, r2, r4 - r8, lr} + .endm + + .macro load_regs + ldmfd sp!, {r1, r2, r4 - r8, pc} + .endm + + .macro load1b, reg1 + ldrusr \reg1, r0, 1 + .endm + + .macro load2b, reg1, reg2 + ldrusr \reg1, r0, 1 + ldrusr \reg2, r0, 1 + .endm + + .macro load1l, reg1 + ldrusr \reg1, r0, 4 + .endm + + .macro load2l, reg1, reg2 + ldrusr \reg1, r0, 4 + ldrusr \reg2, r0, 4 + .endm + + .macro load4l, reg1, reg2, reg3, reg4 + ldrusr \reg1, r0, 4 + ldrusr \reg2, r0, 4 + ldrusr \reg3, r0, 4 + ldrusr \reg4, r0, 4 + .endm + +/* + * unsigned int + * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) + * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr + * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT + */ + +#define FN_ENTRY ENTRY(csum_partial_copy_from_user) +#define FN_EXIT ENDPROC(csum_partial_copy_from_user) + +#include "csumpartialcopygeneric.S" + +/* + * FIXME: minor buglet here + * We don't return the checksum for the data present in the buffer. To do + * so properly, we would have to add in whatever registers were loaded before + * the fault, which, with the current asm above is not predictable. + */ + .pushsection .fixup,"ax" + .align 4 +9001: mov r4, #-EFAULT + ldr r5, [sp, #8*4] @ *err_ptr + str r4, [r5] + ldmia sp, {r1, r2} @ retrieve dst, len + add r2, r2, r1 + mov r0, #0 @ zero the buffer +9002: teq r2, r1 + strneb r0, [r1], #1 + bne 9002b + load_regs + .popsection -- cgit v1.2.3