| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm26/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 | #include <linux/config.h> |
| 11 | #include <linux/linkage.h> |
| 12 | #include <asm/assembler.h> |
| 13 | #include <asm/errno.h> |
| 14 | #include <asm/asm_offsets.h> |
| 15 | |
| 16 | .text |
| 17 | |
| 18 | .macro save_regs |
| 19 | stmfd sp!, {r1 - r2, r4 - r9, fp, ip, lr, pc} |
| 20 | mov r9, sp, lsr #13 |
| 21 | mov r9, r9, lsl #13 |
| 22 | ldr r9, [r9, #TSK_ADDR_LIMIT] |
| 23 | mov r9, r9, lsr #24 |
| 24 | .endm |
| 25 | |
| 26 | .macro load_regs,flags |
| 27 | ldm\flags fp, {r1, r2, r4-r9, fp, sp, pc}^ |
| 28 | .endm |
| 29 | |
| 30 | .macro load1b, reg1 |
| 31 | tst r9, #0x01 |
| 32 | 9999: ldreqbt \reg1, [r0], #1 |
| 33 | ldrneb \reg1, [r0], #1 |
| 34 | .section __ex_table, "a" |
| 35 | .align 3 |
| 36 | .long 9999b, 6001f |
| 37 | .previous |
| 38 | .endm |
| 39 | |
| 40 | .macro load2b, reg1, reg2 |
| 41 | tst r9, #0x01 |
| 42 | 9999: ldreqbt \reg1, [r0], #1 |
| 43 | ldrneb \reg1, [r0], #1 |
| 44 | 9998: ldreqbt \reg2, [r0], #1 |
| 45 | ldrneb \reg2, [r0], #1 |
| 46 | .section __ex_table, "a" |
| 47 | .long 9999b, 6001f |
| 48 | .long 9998b, 6001f |
| 49 | .previous |
| 50 | .endm |
| 51 | |
| 52 | .macro load1l, reg1 |
| 53 | tst r9, #0x01 |
| 54 | 9999: ldreqt \reg1, [r0], #4 |
| 55 | ldrne \reg1, [r0], #4 |
| 56 | .section __ex_table, "a" |
| 57 | .align 3 |
| 58 | .long 9999b, 6001f |
| 59 | .previous |
| 60 | .endm |
| 61 | |
| 62 | .macro load2l, reg1, reg2 |
| 63 | tst r9, #0x01 |
| 64 | ldmneia r0!, {\reg1, \reg2} |
| 65 | 9999: ldreqt \reg1, [r0], #4 |
| 66 | 9998: ldreqt \reg2, [r0], #4 |
| 67 | .section __ex_table, "a" |
| 68 | .long 9999b, 6001f |
| 69 | .long 9998b, 6001f |
| 70 | .previous |
| 71 | .endm |
| 72 | |
| 73 | .macro load4l, reg1, reg2, reg3, reg4 |
| 74 | tst r9, #0x01 |
| 75 | ldmneia r0!, {\reg1, \reg2, \reg3, \reg4} |
| 76 | 9999: ldreqt \reg1, [r0], #4 |
| 77 | 9998: ldreqt \reg2, [r0], #4 |
| 78 | 9997: ldreqt \reg3, [r0], #4 |
| 79 | 9996: ldreqt \reg4, [r0], #4 |
| 80 | .section __ex_table, "a" |
| 81 | .long 9999b, 6001f |
| 82 | .long 9998b, 6001f |
| 83 | .long 9997b, 6001f |
| 84 | .long 9996b, 6001f |
| 85 | .previous |
| 86 | .endm |
| 87 | |
| 88 | /* |
| 89 | * unsigned int |
| 90 | * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) |
| 91 | * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr |
| 92 | * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT |
| 93 | */ |
| 94 | |
| 95 | #define FN_ENTRY ENTRY(csum_partial_copy_from_user) |
| 96 | |
| 97 | #include "csumpartialcopygeneric.S" |
| 98 | |
| 99 | /* |
| 100 | * FIXME: minor buglet here |
| 101 | * We don't return the checksum for the data present in the buffer. To do |
| 102 | * so properly, we would have to add in whatever registers were loaded before |
| 103 | * the fault, which, with the current asm above is not predictable. |
| 104 | */ |
| 105 | .align 4 |
| 106 | 6001: mov r4, #-EFAULT |
| 107 | ldr r5, [fp, #4] @ *err_ptr |
| 108 | str r4, [r5] |
| 109 | ldmia sp, {r1, r2} @ retrieve dst, len |
| 110 | add r2, r2, r1 |
| 111 | mov r0, #0 @ zero the buffer |
| 112 | 6002: teq r2, r1 |
| 113 | strneb r0, [r1], #1 |
| 114 | bne 6002b |
| 115 | load_regs ea |