cregit-Linux how code gets into the kernel

Release 4.14 arch/parisc/include/asm/checksum.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PARISC_CHECKSUM_H

#define _PARISC_CHECKSUM_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
 */
extern __wsum csum_partial(const void *, int, __wsum);

/*
 * The same as csum_partial, but copies from src while it checksums.
 *
 * Here even more important to align src and dst on a 32-bit (or even
 * better 64-bit) boundary
 */
extern __wsum csum_partial_copy_nocheck(const void *, void *, int, __wsum);

/*
 * this is a new version of the above that records errors it finds in *errp,
 * but continues and zeros the rest of the buffer.
 */
extern __wsum csum_partial_copy_from_user(const void __user *src,
		void *dst, int len, __wsum sum, int *errp);

/*
 *      Optimized for IP headers, which always checksum on 4 octet boundaries.
 *
 *      Written by Randolph Chung <tausq@debian.org>, and then mucked with by
 *      LaMont Jones <lamont@debian.org>
 */

static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) { unsigned int sum; __asm__ __volatile__ ( " ldws,ma 4(%1), %0\n" " addib,<= -4, %2, 2f\n" "\n" " ldws 4(%1), %%r20\n" " ldws 8(%1), %%r21\n" " add %0, %%r20, %0\n" " ldws,ma 12(%1), %%r19\n" " addc %0, %%r21, %0\n" " addc %0, %%r19, %0\n" "1: ldws,ma 4(%1), %%r19\n" " addib,< 0, %2, 1b\n" " addc %0, %%r19, %0\n" "\n" " extru %0, 31, 16, %%r20\n" " extru %0, 15, 16, %%r21\n" " addc %%r20, %%r21, %0\n" " extru %0, 15, 16, %%r21\n" " add %0, %%r21, %0\n" " subi -1, %0, %0\n" "2:\n" : "=r" (sum), "=r" (iph), "=r" (ihl) : "1" (iph), "2" (ihl) : "r19", "r20", "r21", "memory"); return (__force __sum16)sum; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2376.67%133.33%
Al Viro620.00%133.33%
Kyle McMartin13.33%133.33%
Total30100.00%3100.00%

/* * Fold a partial checksum */
static inline __sum16 csum_fold(__wsum csum) { u32 sum = (__force u32)csum; /* add the swapped two 16-bit halves of sum, a possible carry from adding the two 16-bit halves, will carry from the lower half into the upper half, giving us the correct sum in the upper half. */ sum += (sum << 16) + (sum >> 16); return (__force __sum16)(~sum >> 16); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2247.83%133.33%
Al Viro1839.13%133.33%
Matthew Wilcox613.04%133.33%
Total46100.00%3100.00%


static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, __u8 proto, __wsum sum) { __asm__( " add %1, %0, %0\n" " addc %2, %0, %0\n" " addc %3, %0, %0\n" " addc %%r0, %0, %0\n" : "=r" (sum) : "r" (daddr), "r"(saddr), "r"(proto+len), "0"(sum)); return sum; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)1973.08%133.33%
Al Viro519.23%133.33%
Alexander Duyck27.69%133.33%
Total26100.00%3100.00%

/* * 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)); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)3384.62%133.33%
Al Viro410.26%133.33%
Alexander Duyck25.13%133.33%
Total39100.00%3100.00%

/* * this routine is used for miscellaneous IP-like checksums, mainly * in icmp.c */
static inline __sum16 ip_compute_csum(const void *buf, int len) { return csum_fold (csum_partial(buf, len, 0)); }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)2589.29%150.00%
Al Viro310.71%150.00%
Total28100.00%2100.00%

#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 sum) { __asm__ __volatile__ ( #if BITS_PER_LONG > 32 /* ** We can execute two loads and two adds per cycle on PA 8000. ** But add insn's get serialized waiting for the carry bit. ** Try to keep 4 registers with "live" values ahead of the ALU. */ " ldd,ma 8(%1), %%r19\n" /* get 1st saddr word */ " ldd,ma 8(%2), %%r20\n" /* get 1st daddr word */ " add %8, %3, %3\n"/* add 16-bit proto + len */ " add %%r19, %0, %0\n" " ldd,ma 8(%1), %%r21\n" /* 2cd saddr */ " ldd,ma 8(%2), %%r22\n" /* 2cd daddr */ " add,dc %%r20, %0, %0\n" " add,dc %%r21, %0, %0\n" " add,dc %%r22, %0, %0\n" " add,dc %3, %0, %0\n" /* fold in proto+len | carry bit */ " extrd,u %0, 31, 32, %%r19\n" /* copy upper half down */ " depdi 0, 31, 32, %0\n" /* clear upper half */ " add %%r19, %0, %0\n" /* fold into 32-bits */ " addc 0, %0, %0\n" /* add carry */ #else /* ** For PA 1.x, the insn order doesn't matter as much. ** Insn stream is serialized on the carry bit here too. ** result from the previous operation (eg r0 + x) */ " ldw,ma 4(%1), %%r19\n" /* get 1st saddr word */ " ldw,ma 4(%2), %%r20\n" /* get 1st daddr word */ " add %8, %3, %3\n" /* add 16-bit proto + len */ " add %%r19, %0, %0\n" " ldw,ma 4(%1), %%r21\n" /* 2cd saddr */ " addc %%r20, %0, %0\n" " ldw,ma 4(%2), %%r22\n" /* 2cd daddr */ " addc %%r21, %0, %0\n" " ldw,ma 4(%1), %%r19\n" /* 3rd saddr */ " addc %%r22, %0, %0\n" " ldw,ma 4(%2), %%r20\n" /* 3rd daddr */ " addc %%r19, %0, %0\n" " ldw,ma 4(%1), %%r21\n" /* 4th saddr */ " addc %%r20, %0, %0\n" " ldw,ma 4(%2), %%r22\n" /* 4th daddr */ " addc %%r21, %0, %0\n" " addc %%r22, %0, %0\n" " addc %3, %0, %0\n" /* fold in proto+len, catch carry */ #endif : "=r" (sum), "=r" (saddr), "=r" (daddr), "=r" (len) : "0" (sum), "1" (saddr), "2" (daddr), "3" (len), "r" (proto) : "r19", "r20", "r21", "r22", "memory"); return csum_fold(sum); }

Contributors

PersonTokensPropCommitsCommitProp
Matthew Wilcox5460.67%120.00%
Linus Torvalds (pre-git)2831.46%120.00%
Al Viro55.62%120.00%
Alexander Duyck11.12%120.00%
Kyle McMartin11.12%120.00%
Total89100.00%5100.00%

/* * Copy and checksum to user */ #define HAVE_CSUM_COPY_USER
static __inline__ __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len, __wsum sum, int *err_ptr) { /* code stolen from include/asm-mips64 */ sum = csum_partial(src, len, sum); if (copy_to_user(dst, src, len)) { *err_ptr = -EFAULT; return (__force __wsum)-1; } return sum; }

Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)6086.96%133.33%
Al Viro811.59%133.33%
Stephen Hemminger11.45%133.33%
Total69100.00%3100.00%

#endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Linus Torvalds (pre-git)27066.34%17.69%
Matthew Wilcox6415.72%323.08%
Al Viro6014.74%17.69%
Alexander Duyck51.23%215.38%
Arnaldo Carvalho de Melo30.74%17.69%
Kyle McMartin20.49%215.38%
David S. Miller10.25%17.69%
Stephen Hemminger10.25%17.69%
Greg Kroah-Hartman10.25%17.69%
Total407100.00%13100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.