diff options
author | 2015-08-04 12:17:53 -0700 | |
---|---|---|
committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/s390/include/asm/checksum.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/s390/include/asm/checksum.h')
-rw-r--r-- | kernel/arch/s390/include/asm/checksum.h | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/kernel/arch/s390/include/asm/checksum.h b/kernel/arch/s390/include/asm/checksum.h new file mode 100644 index 000000000..740364856 --- /dev/null +++ b/kernel/arch/s390/include/asm/checksum.h @@ -0,0 +1,140 @@ +/* + * 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 <asm/uaccess.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; +} + +/* + * the same as csum_partial_copy, but copies from user space. + * + * here even more important to align src and dst on a 32-bit (or even + * better 64-bit) boundary + * + * Copy from userspace and compute checksum. + */ +static inline __wsum +csum_partial_copy_from_user(const void __user *src, void *dst, + int len, __wsum sum, + int *err_ptr) +{ + if (unlikely(copy_from_user(dst, src, len))) + *err_ptr = -EFAULT; + return csum_partial(dst, len, sum); +} + + +static inline __wsum +csum_partial_copy_nocheck (const void *src, void *dst, int len, __wsum sum) +{ + memcpy(dst,src,len); + return csum_partial(dst, len, 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 checksum on 4 octet boundaries. + * + */ +static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) +{ + return csum_fold(csum_partial(iph, ihl*4, 0)); +} + +/* + * computes the checksum of the TCP/UDP pseudo-header + * returns a 32-bit checksum + */ +static inline __wsum +csum_tcpudp_nofold(__be32 saddr, __be32 daddr, + unsigned short len, unsigned short proto, + __wsum sum) +{ + __u32 csum = (__force __u32)sum; + + csum += (__force __u32)saddr; + if (csum < (__force __u32)saddr) + csum++; + + csum += (__force __u32)daddr; + if (csum < (__force __u32)daddr) + csum++; + + csum += len + proto; + if (csum < len + proto) + csum++; + + return (__force __wsum)csum; +} + +/* + * 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, + unsigned short len, unsigned short proto, + __wsum sum) +{ + return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,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 /* _S390_CHECKSUM_H */ + + |