1/* 2 * linux/arch/arm/lib/csumpartialcopyuser.S 3 * 4 * Copyright (C) 1995-1998 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * 27/03/03 Ian Molton Clean up CONFIG_CPU 11 * 12 */ 13#include <linux/linkage.h> 14#include <asm/assembler.h> 15#include <asm/errno.h> 16#include <asm/asm-offsets.h> 17 18 .text 19 20 .macro save_regs 21 stmfd sp!, {r1, r2, r4 - r8, lr} 22 .endm 23 24 .macro load_regs 25 ldmfd sp!, {r1, r2, r4 - r8, pc} 26 .endm 27 28 .macro load1b, reg1 29 ldrusr \reg1, r0, 1 30 .endm 31 32 .macro load2b, reg1, reg2 33 ldrusr \reg1, r0, 1 34 ldrusr \reg2, r0, 1 35 .endm 36 37 .macro load1l, reg1 38 ldrusr \reg1, r0, 4 39 .endm 40 41 .macro load2l, reg1, reg2 42 ldrusr \reg1, r0, 4 43 ldrusr \reg2, r0, 4 44 .endm 45 46 .macro load4l, reg1, reg2, reg3, reg4 47 ldrusr \reg1, r0, 4 48 ldrusr \reg2, r0, 4 49 ldrusr \reg3, r0, 4 50 ldrusr \reg4, r0, 4 51 .endm 52 53/* 54 * unsigned int 55 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) 56 * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr 57 * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT 58 */ 59 60#define FN_ENTRY ENTRY(csum_partial_copy_from_user) 61#define FN_EXIT ENDPROC(csum_partial_copy_from_user) 62 63#include "csumpartialcopygeneric.S" 64 65/* 66 * FIXME: minor buglet here 67 * We don't return the checksum for the data present in the buffer. To do 68 * so properly, we would have to add in whatever registers were loaded before 69 * the fault, which, with the current asm above is not predictable. 70 */ 71 .pushsection .fixup,"ax" 72 .align 4 739001: mov r4, #-EFAULT 74 ldr r5, [sp, #8*4] @ *err_ptr 75 str r4, [r5] 76 ldmia sp, {r1, r2} @ retrieve dst, len 77 add r2, r2, r1 78 mov r0, #0 @ zero the buffer 799002: teq r2, r1 80 strneb r0, [r1], #1 81 bne 9002b 82 load_regs 83 .popsection 84