diff options
Diffstat (limited to 'arch/powerpc/include/asm/checksum.h')
| -rw-r--r-- | arch/powerpc/include/asm/checksum.h | 141 |
1 files changed, 101 insertions, 40 deletions
diff --git a/arch/powerpc/include/asm/checksum.h b/arch/powerpc/include/asm/checksum.h index e8d9ef4755a4..ee655ed1ff1b 100644 --- a/arch/powerpc/include/asm/checksum.h +++ b/arch/powerpc/include/asm/checksum.h @@ -9,30 +9,9 @@ * 2 of the License, or (at your option) any later version. */ -/* - * This is a version of ip_compute_csum() optimized for IP headers, - * which always checksum on 4 octet boundaries. ihl is the number - * of 32-bit words and is always >= 5. - */ #ifdef CONFIG_GENERIC_CSUM #include <asm-generic/checksum.h> #else -extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); - -/* - * computes the checksum of a memory block at buff, length len, - * and adds in "sum" (32-bit) - * - * returns a 32-bit number suitable for feeding into itself - * or csum_tcpudp_magic - * - * this function must be called with even lengths, except - * for the last fragment, which may be odd - * - * it's best to have buff aligned on a 32-bit boundary - */ -extern __wsum csum_partial(const void *buff, int len, __wsum sum); - /* * Computes the checksum of a memory block at src, length len, * and adds in "sum" (32-bit), while copying the block to dst. @@ -47,21 +26,12 @@ extern __wsum csum_partial_copy_generic(const void *src, void *dst, int len, __wsum sum, int *src_err, int *dst_err); -#ifdef __powerpc64__ #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER extern __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr); #define HAVE_CSUM_COPY_USER extern __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len, __wsum sum, int *err_ptr); -#else -/* - * the same as csum_partial, but copies from src to dst while it - * checksums. - */ -#define csum_partial_copy_from_user(src, dst, len, sum, errp) \ - csum_partial_copy_generic((__force const void *)(src), (dst), (len), (sum), (errp), NULL) -#endif #define csum_partial_copy_nocheck(src, dst, len, sum) \ csum_partial_copy_generic((src), (dst), (len), (sum), NULL, NULL) @@ -83,15 +53,6 @@ static inline __sum16 csum_fold(__wsum sum) return (__force __sum16)(~((__force u32)sum + tmp) >> 16); } -/* - * this routine is used for miscellaneous IP-like checksums, mainly - * in icmp.c - */ -static inline __sum16 ip_compute_csum(const void *buff, int len) -{ - return csum_fold(csum_partial(buff, len, 0)); -} - static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, unsigned short proto, @@ -135,17 +96,117 @@ static inline __wsum csum_add(__wsum csum, __wsum addend) { #ifdef __powerpc64__ u64 res = (__force u64)csum; +#endif + if (__builtin_constant_p(csum) && csum == 0) + return addend; + if (__builtin_constant_p(addend) && addend == 0) + return csum; +#ifdef __powerpc64__ res += (__force u64)addend; return (__force __wsum)((u32)res + (res >> 32)); #else asm("addc %0,%0,%1;" "addze %0,%0;" - : "+r" (csum) : "r" (addend)); + : "+r" (csum) : "r" (addend) : "xer"); return csum; #endif } +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksum on 4 octet boundaries. ihl is the number + * of 32-bit words and is always >= 5. + */ +static inline __wsum ip_fast_csum_nofold(const void *iph, unsigned int ihl) +{ + const u32 *ptr = (const u32 *)iph + 1; +#ifdef __powerpc64__ + unsigned int i; + u64 s = *(const u32 *)iph; + + for (i = 0; i < ihl - 1; i++, ptr++) + s += *ptr; + s += (s >> 32); + return (__force __wsum)s; +#else + __wsum sum, tmp; + + asm("mtctr %3;" + "addc %0,%4,%5;" + "1: lwzu %1, 4(%2);" + "adde %0,%0,%1;" + "bdnz 1b;" + "addze %0,%0;" + : "=r" (sum), "=r" (tmp), "+b" (ptr) + : "r" (ihl - 2), "r" (*(const u32 *)iph), "r" (*ptr) + : "ctr", "xer", "memory"); + + return sum; +#endif +} + +static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + return csum_fold(ip_fast_csum_nofold(iph, ihl)); +} + +/* + * computes the checksum of a memory block at buff, length len, + * and adds in "sum" (32-bit) + * + * returns a 32-bit number suitable for feeding into itself + * or csum_tcpudp_magic + * + * this function must be called with even lengths, except + * for the last fragment, which may be odd + * + * it's best to have buff aligned on a 32-bit boundary + */ +__wsum __csum_partial(const void *buff, int len, __wsum sum); + +static inline __wsum csum_partial(const void *buff, int len, __wsum sum) +{ + if (__builtin_constant_p(len) && len <= 16 && (len & 1) == 0) { + if (len == 2) + sum = csum_add(sum, (__force __wsum)*(const u16 *)buff); + if (len >= 4) + sum = csum_add(sum, (__force __wsum)*(const u32 *)buff); + if (len == 6) + sum = csum_add(sum, (__force __wsum) + *(const u16 *)(buff + 4)); + if (len >= 8) + sum = csum_add(sum, (__force __wsum) + *(const u32 *)(buff + 4)); + if (len == 10) + sum = csum_add(sum, (__force __wsum) + *(const u16 *)(buff + 8)); + if (len >= 12) + sum = csum_add(sum, (__force __wsum) + *(const u32 *)(buff + 8)); + if (len == 14) + sum = csum_add(sum, (__force __wsum) + *(const u16 *)(buff + 12)); + if (len >= 16) + sum = csum_add(sum, (__force __wsum) + *(const u32 *)(buff + 12)); + } else if (__builtin_constant_p(len) && (len & 3) == 0) { + sum = csum_add(sum, ip_fast_csum_nofold(buff, len >> 2)); + } else { + sum = __csum_partial(buff, len, sum); + } + return sum; +} + +/* + * this routine is used for miscellaneous IP-like checksums, mainly + * in icmp.c + */ +static inline __sum16 ip_compute_csum(const void *buff, int len) +{ + return csum_fold(csum_partial(buff, len, 0)); +} + #endif #endif /* __KERNEL__ */ #endif |
