projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b920de1b DH |
1 | /* MN10300 Optimised checksumming wrappers |
| 2 | * | |
| 3 | * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd. | |
| 4 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
| 5 | * Written by David Howells (dhowells@redhat.com) | |
| 6 | * | |
| 7 | * This program is free software; you can redistribute it and/or | |
| 8 | * modify it under the terms of the GNU General Public Licence | |
| 9 | * as published by the Free Software Foundation; either version | |
| 10 | * 2 of the Licence, or (at your option) any later version. | |
| 11 | */ | |
| 12 | #include <linux/module.h> | |
| 13 | #include <linux/errno.h> | |
| 14 | #include <asm/byteorder.h> | |
| 15 | #include <asm/uaccess.h> | |
| 16 | #include <asm/checksum.h> | |
| 17 | #include "internal.h" | |
| 18 | ||
| 19 | static inline unsigned short from32to16(__wsum sum) | |
| 20 | { | |
| 21 | asm(" add %1,%0 \n" | |
| 22 | " addc 0xffff,%0 \n" | |
| 23 | : "=r" (sum) | |
| 24 | : "r" (sum << 16), "0" (sum & 0xffff0000) | |
| d6bb7a1a | 25 | : "cc" |
| b920de1b DH |
26 | ); |
| 27 | return sum >> 16; | |
| 28 | } | |
| 29 | ||
| 30 | __sum16 ip_fast_csum(const void *iph, unsigned int ihl) | |
| 31 | { | |
| 32 | return ~do_csum(iph, ihl * 4); | |
| 33 | } | |
| 34 | EXPORT_SYMBOL(ip_fast_csum); | |
| 35 | ||
| 36 | __wsum csum_partial(const void *buff, int len, __wsum sum) | |
| 37 | { | |
| 38 | __wsum result; | |
| 39 | ||
| 40 | result = do_csum(buff, len); | |
| 41 | result += sum; | |
| 42 | if (sum > result) | |
| 43 | result++; | |
| 44 | return result; | |
| 45 | } | |
| 46 | EXPORT_SYMBOL(csum_partial); | |
| 47 | ||
| 48 | __sum16 ip_compute_csum(const void *buff, int len) | |
| 49 | { | |
| 50 | return ~from32to16(do_csum(buff, len)); | |
| 51 | } | |
| 52 | EXPORT_SYMBOL(ip_compute_csum); | |
| 53 | ||
| 54 | __wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum) | |
| 55 | { | |
| 56 | copy_from_user(dst, src, len); | |
| 57 | return csum_partial(dst, len, sum); | |
| 58 | } | |
| 59 | EXPORT_SYMBOL(csum_partial_copy); | |
| 60 | ||
| 61 | __wsum csum_partial_copy_nocheck(const void *src, void *dst, | |
| 62 | int len, __wsum sum) | |
| 63 | { | |
| 64 | sum = csum_partial(src, len, sum); | |
| 65 | memcpy(dst, src, len); | |
| 66 | return sum; | |
| 67 | } | |
| 68 | EXPORT_SYMBOL(csum_partial_copy_nocheck); | |
| 69 | ||
| 70 | __wsum csum_partial_copy_from_user(const void *src, void *dst, | |
| 71 | int len, __wsum sum, | |
| 72 | int *err_ptr) | |
| 73 | { | |
| 74 | int missing; | |
| 75 | ||
| 76 | missing = copy_from_user(dst, src, len); | |
| 77 | if (missing) { | |
| 78 | memset(dst + len - missing, 0, missing); | |
| 79 | *err_ptr = -EFAULT; | |
| 80 | } | |
| 81 | ||
| 82 | return csum_partial(dst, len, sum); | |
| 83 | } | |
| 84 | EXPORT_SYMBOL(csum_partial_copy_from_user); | |
| 85 | ||
| 86 | __wsum csum_and_copy_to_user(const void *src, void *dst, | |
| 87 | int len, __wsum sum, | |
| 88 | int *err_ptr) | |
| 89 | { | |
| 90 | int missing; | |
| 91 | ||
| 92 | missing = copy_to_user(dst, src, len); | |
| 93 | if (missing) { | |
| 94 | memset(dst + len - missing, 0, missing); | |
| 95 | *err_ptr = -EFAULT; | |
| 96 | } | |
| 97 | ||
| 98 | return csum_partial(src, len, sum); | |
| 99 | } | |
| 100 | EXPORT_SYMBOL(csum_and_copy_to_user); |