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#ifdef CONFIG_CPU_SW_DOMAIN_PAN 21 .macro save_regs 22 mrc p15, 0, ip, c3, c0, 0 23 stmfd sp!, {r1, r2, r4 - r8, ip, lr} 24 uaccess_enable ip 25 .endm 26 27 .macro load_regs 28 ldmfd sp!, {r1, r2, r4 - r8, ip, lr} 29 mcr p15, 0, ip, c3, c0, 0 30 ret lr 31 .endm 32#else 33 .macro save_regs 34 stmfd sp!, {r1, r2, r4 - r8, lr} 35 .endm 36 37 .macro load_regs 38 ldmfd sp!, {r1, r2, r4 - r8, pc} 39 .endm 40#endif 41 42 .macro load1b, reg1 43 ldrusr \reg1, r0, 1 44 .endm 45 46 .macro load2b, reg1, reg2 47 ldrusr \reg1, r0, 1 48 ldrusr \reg2, r0, 1 49 .endm 50 51 .macro load1l, reg1 52 ldrusr \reg1, r0, 4 53 .endm 54 55 .macro load2l, reg1, reg2 56 ldrusr \reg1, r0, 4 57 ldrusr \reg2, r0, 4 58 .endm 59 60 .macro load4l, reg1, reg2, reg3, reg4 61 ldrusr \reg1, r0, 4 62 ldrusr \reg2, r0, 4 63 ldrusr \reg3, r0, 4 64 ldrusr \reg4, r0, 4 65 .endm 66 67/* 68 * unsigned int 69 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) 70 * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr 71 * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT 72 */ 73 74#define FN_ENTRY ENTRY(csum_partial_copy_from_user) 75#define FN_EXIT ENDPROC(csum_partial_copy_from_user) 76 77#include "csumpartialcopygeneric.S" 78 79/* 80 * FIXME: minor buglet here 81 * We don't return the checksum for the data present in the buffer. To do 82 * so properly, we would have to add in whatever registers were loaded before 83 * the fault, which, with the current asm above is not predictable. 84 */ 85 .pushsection .text.fixup,"ax" 86 .align 4 879001: mov r4, #-EFAULT 88#ifdef CONFIG_CPU_SW_DOMAIN_PAN 89 ldr r5, [sp, #9*4] @ *err_ptr 90#else 91 ldr r5, [sp, #8*4] @ *err_ptr 92#endif 93 str r4, [r5] 94 ldmia sp, {r1, r2} @ retrieve dst, len 95 add r2, r2, r1 96 mov r0, #0 @ zero the buffer 979002: teq r2, r1 98 strneb r0, [r1], #1 99 bne 9002b 100 load_regs 101 .popsection 102