diff options
Diffstat (limited to 'arch/x86/lib/csum-wrappers_64.c')
| -rw-r--r-- | arch/x86/lib/csum-wrappers_64.c | 147 |
1 files changed, 81 insertions, 66 deletions
diff --git a/arch/x86/lib/csum-wrappers_64.c b/arch/x86/lib/csum-wrappers_64.c index fd42a4a095f..459b58a8a15 100644 --- a/arch/x86/lib/csum-wrappers_64.c +++ b/arch/x86/lib/csum-wrappers_64.c @@ -1,117 +1,129 @@ -/* Copyright 2002,2003 Andi Kleen, SuSE Labs. +/* + * Copyright 2002, 2003 Andi Kleen, SuSE Labs. * Subject to the GNU Public License v.2 - * + * * Wrappers of assembly checksum functions for x86-64. */ - #include <asm/checksum.h> #include <linux/module.h> -/** - * csum_partial_copy_from_user - Copy and checksum from user space. - * @src: source address (user space) +/** + * csum_partial_copy_from_user - Copy and checksum from user space. + * @src: source address (user space) * @dst: destination address * @len: number of bytes to be copied. * @isum: initial sum that is added into the result (32bit unfolded) * @errp: set to -EFAULT for an bad source address. - * + * * Returns an 32bit unfolded checksum of the buffer. - * src and dst are best aligned to 64bits. - */ + * src and dst are best aligned to 64bits. + */ __wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum isum, int *errp) -{ +{ might_sleep(); *errp = 0; - if (likely(access_ok(VERIFY_READ,src, len))) { - /* Why 6, not 7? To handle odd addresses aligned we - would need to do considerable complications to fix the - checksum which is defined as an 16bit accumulator. The - fix alignment code is primarily for performance - compatibility with 32bit and that will handle odd - addresses slowly too. */ - if (unlikely((unsigned long)src & 6)) { - while (((unsigned long)src & 6) && len >= 2) { - __u16 val16; - *errp = __get_user(val16, (const __u16 __user *)src); - if (*errp) - return isum; - *(__u16 *)dst = val16; - isum = (__force __wsum)add32_with_carry( - (__force unsigned)isum, val16); - src += 2; - dst += 2; - len -= 2; - } + + if (!likely(access_ok(VERIFY_READ, src, len))) + goto out_err; + + /* + * Why 6, not 7? To handle odd addresses aligned we + * would need to do considerable complications to fix the + * checksum which is defined as an 16bit accumulator. The + * fix alignment code is primarily for performance + * compatibility with 32bit and that will handle odd + * addresses slowly too. + */ + if (unlikely((unsigned long)src & 6)) { + while (((unsigned long)src & 6) && len >= 2) { + __u16 val16; + + *errp = __get_user(val16, (const __u16 __user *)src); + if (*errp) + return isum; + + *(__u16 *)dst = val16; + isum = (__force __wsum)add32_with_carry( + (__force unsigned)isum, val16); + src += 2; + dst += 2; + len -= 2; } - isum = csum_partial_copy_generic((__force const void *)src, - dst, len, isum, errp, NULL); - if (likely(*errp == 0)) - return isum; - } + } + isum = csum_partial_copy_generic((__force const void *)src, + dst, len, isum, errp, NULL); + if (unlikely(*errp)) + goto out_err; + + return isum; + +out_err: *errp = -EFAULT; - memset(dst,0,len); - return isum; -} + memset(dst, 0, len); + return isum; +} EXPORT_SYMBOL(csum_partial_copy_from_user); -/** - * csum_partial_copy_to_user - Copy and checksum to user space. +/** + * csum_partial_copy_to_user - Copy and checksum to user space. * @src: source address * @dst: destination address (user space) * @len: number of bytes to be copied. * @isum: initial sum that is added into the result (32bit unfolded) * @errp: set to -EFAULT for an bad destination address. - * + * * Returns an 32bit unfolded checksum of the buffer. * src and dst are best aligned to 64bits. - */ + */ __wsum csum_partial_copy_to_user(const void *src, void __user *dst, int len, __wsum isum, int *errp) -{ +{ might_sleep(); + if (unlikely(!access_ok(VERIFY_WRITE, dst, len))) { *errp = -EFAULT; - return 0; + return 0; } if (unlikely((unsigned long)dst & 6)) { - while (((unsigned long)dst & 6) && len >= 2) { + while (((unsigned long)dst & 6) && len >= 2) { __u16 val16 = *(__u16 *)src; + isum = (__force __wsum)add32_with_carry( (__force unsigned)isum, val16); *errp = __put_user(val16, (__u16 __user *)dst); if (*errp) return isum; - src += 2; - dst += 2; + src += 2; + dst += 2; len -= 2; } } *errp = 0; - return csum_partial_copy_generic(src, (void __force *)dst,len,isum,NULL,errp); -} - + return csum_partial_copy_generic(src, (void __force *)dst, + len, isum, NULL, errp); +} EXPORT_SYMBOL(csum_partial_copy_to_user); -/** +/** * csum_partial_copy_nocheck - Copy and checksum. * @src: source address * @dst: destination address * @len: number of bytes to be copied. * @isum: initial sum that is added into the result (32bit unfolded) - * + * * Returns an 32bit unfolded checksum of the buffer. - */ + */ __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len, __wsum sum) -{ - return csum_partial_copy_generic(src,dst,len,sum,NULL,NULL); -} +{ + return csum_partial_copy_generic(src, dst, len, sum, NULL, NULL); +} EXPORT_SYMBOL(csum_partial_copy_nocheck); __sum16 csum_ipv6_magic(const struct in6_addr *saddr, @@ -119,17 +131,20 @@ __sum16 csum_ipv6_magic(const struct in6_addr *saddr, __u32 len, unsigned short proto, __wsum sum) { __u64 rest, sum64; - + rest = (__force __u64)htonl(len) + (__force __u64)htons(proto) + (__force __u64)sum; - asm(" addq (%[saddr]),%[sum]\n" - " adcq 8(%[saddr]),%[sum]\n" - " adcq (%[daddr]),%[sum]\n" - " adcq 8(%[daddr]),%[sum]\n" - " adcq $0,%[sum]\n" - : [sum] "=r" (sum64) - : "[sum]" (rest),[saddr] "r" (saddr), [daddr] "r" (daddr)); - return csum_fold((__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32)); -} + asm(" addq (%[saddr]),%[sum]\n" + " adcq 8(%[saddr]),%[sum]\n" + " adcq (%[daddr]),%[sum]\n" + " adcq 8(%[daddr]),%[sum]\n" + " adcq $0,%[sum]\n" + + : [sum] "=r" (sum64) + : "[sum]" (rest), [saddr] "r" (saddr), [daddr] "r" (daddr)); + + return csum_fold( + (__force __wsum)add32_with_carry(sum64 & 0xffffffff, sum64>>32)); +} EXPORT_SYMBOL(csum_ipv6_magic); |