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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /arch/s390/include/asm/checksum.h | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/s390/include/asm/checksum.h')
-rw-r--r-- | arch/s390/include/asm/checksum.h | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/s390/include/asm/checksum.h b/arch/s390/include/asm/checksum.h new file mode 100644 index 000000000..a8c02cfbc --- /dev/null +++ b/arch/s390/include/asm/checksum.h @@ -0,0 +1,130 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * S390 fast network checksum routines + * + * S390 version + * Copyright IBM Corp. 1999 + * Author(s): Ulrich Hild (first version) + * Martin Schwidefsky (heavily optimized CKSM version) + * D.J. Barrow (third attempt) + */ + +#ifndef _S390_CHECKSUM_H +#define _S390_CHECKSUM_H + +#include <linux/uaccess.h> +#include <linux/in6.h> + +/* + * 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. + */ +static inline __wsum csum_partial(const void *buff, int len, __wsum sum) +{ + register unsigned long reg2 asm("2") = (unsigned long) buff; + register unsigned long reg3 asm("3") = (unsigned long) len; + + asm volatile( + "0: cksm %0,%1\n" /* do checksum on longs */ + " jo 0b\n" + : "+d" (sum), "+d" (reg2), "+d" (reg3) : : "cc", "memory"); + return sum; +} + +/* + * Fold a partial checksum without adding pseudo headers. + */ +static inline __sum16 csum_fold(__wsum sum) +{ + u32 csum = (__force u32) sum; + + csum += (csum >> 16) | (csum << 16); + csum >>= 16; + return (__force __sum16) ~csum; +} + +/* + * This is a version of ip_compute_csum() optimized for IP headers, + * which always checksums on 4 octet boundaries. + */ +static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + __u64 csum = 0; + __u32 *ptr = (u32 *)iph; + + csum += *ptr++; + csum += *ptr++; + csum += *ptr++; + csum += *ptr++; + ihl -= 4; + while (ihl--) + csum += *ptr++; + csum += (csum >> 32) | (csum << 32); + return csum_fold((__force __wsum)(csum >> 32)); +} + +/* + * Computes the checksum of the TCP/UDP pseudo-header. + * Returns a 32-bit checksum. + */ +static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, + __u8 proto, __wsum sum) +{ + __u64 csum = (__force __u64)sum; + + csum += (__force __u32)saddr; + csum += (__force __u32)daddr; + csum += len; + csum += proto; + csum += (csum >> 32) | (csum << 32); + return (__force __wsum)(csum >> 32); +} + +/* + * Computes the checksum of the TCP/UDP pseudo-header. + * Returns a 16-bit checksum, already complemented. + */ +static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len, + __u8 proto, __wsum sum) +{ + return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); +} + +/* + * Used for miscellaneous IP-like checksums, mainly icmp. + */ +static inline __sum16 ip_compute_csum(const void *buff, int len) +{ + return csum_fold(csum_partial(buff, len, 0)); +} + +#define _HAVE_ARCH_IPV6_CSUM +static inline __sum16 csum_ipv6_magic(const struct in6_addr *saddr, + const struct in6_addr *daddr, + __u32 len, __u8 proto, __wsum csum) +{ + __u64 sum = (__force __u64)csum; + + sum += (__force __u32)saddr->s6_addr32[0]; + sum += (__force __u32)saddr->s6_addr32[1]; + sum += (__force __u32)saddr->s6_addr32[2]; + sum += (__force __u32)saddr->s6_addr32[3]; + sum += (__force __u32)daddr->s6_addr32[0]; + sum += (__force __u32)daddr->s6_addr32[1]; + sum += (__force __u32)daddr->s6_addr32[2]; + sum += (__force __u32)daddr->s6_addr32[3]; + sum += len; + sum += proto; + sum += (sum >> 32) | (sum << 32); + return csum_fold((__force __wsum)(sum >> 32)); +} + +#endif /* _S390_CHECKSUM_H */ |