From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- include/net/checksum.h | 191 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 191 insertions(+) create mode 100644 include/net/checksum.h (limited to 'include/net/checksum.h') diff --git a/include/net/checksum.h b/include/net/checksum.h new file mode 100644 index 000000000..3cbab35de --- /dev/null +++ b/include/net/checksum.h @@ -0,0 +1,191 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * INET An implementation of the TCP/IP protocol suite for the LINUX + * operating system. INET is implemented using the BSD Socket + * interface as the means of communication with the user level. + * + * Checksumming functions for IP, TCP, UDP and so on + * + * Authors: Jorge Cwik, + * Arnt Gulbrandsen, + * Borrows very liberally from tcp.c and ip.c, see those + * files for more names. + */ + +#ifndef _CHECKSUM_H +#define _CHECKSUM_H + +#include +#include +#include +#include +#if !defined(_HAVE_ARCH_COPY_AND_CSUM_FROM_USER) || !defined(HAVE_CSUM_COPY_USER) +#include +#endif + +#ifndef _HAVE_ARCH_COPY_AND_CSUM_FROM_USER +static __always_inline +__wsum csum_and_copy_from_user (const void __user *src, void *dst, + int len) +{ + if (copy_from_user(dst, src, len)) + return 0; + return csum_partial(dst, len, ~0U); +} +#endif + +#ifndef HAVE_CSUM_COPY_USER +static __always_inline __wsum csum_and_copy_to_user +(const void *src, void __user *dst, int len) +{ + __wsum sum = csum_partial(src, len, ~0U); + + if (copy_to_user(dst, src, len) == 0) + return sum; + return 0; +} +#endif + +#ifndef _HAVE_ARCH_CSUM_AND_COPY +static __always_inline __wsum +csum_partial_copy_nocheck(const void *src, void *dst, int len) +{ + memcpy(dst, src, len); + return csum_partial(dst, len, 0); +} +#endif + +#ifndef HAVE_ARCH_CSUM_ADD +static __always_inline __wsum csum_add(__wsum csum, __wsum addend) +{ + u32 res = (__force u32)csum; + res += (__force u32)addend; + return (__force __wsum)(res + (res < (__force u32)addend)); +} +#endif + +static __always_inline __wsum csum_sub(__wsum csum, __wsum addend) +{ + return csum_add(csum, ~addend); +} + +static __always_inline __sum16 csum16_add(__sum16 csum, __be16 addend) +{ + u16 res = (__force u16)csum; + + res += (__force u16)addend; + return (__force __sum16)(res + (res < (__force u16)addend)); +} + +static __always_inline __sum16 csum16_sub(__sum16 csum, __be16 addend) +{ + return csum16_add(csum, ~addend); +} + +#ifndef HAVE_ARCH_CSUM_SHIFT +static __always_inline __wsum csum_shift(__wsum sum, int offset) +{ + /* rotate sum to align it with a 16b boundary */ + if (offset & 1) + return (__force __wsum)ror32((__force u32)sum, 8); + return sum; +} +#endif + +static __always_inline __wsum +csum_block_add(__wsum csum, __wsum csum2, int offset) +{ + return csum_add(csum, csum_shift(csum2, offset)); +} + +static __always_inline __wsum +csum_block_sub(__wsum csum, __wsum csum2, int offset) +{ + return csum_block_add(csum, ~csum2, offset); +} + +static __always_inline __wsum csum_unfold(__sum16 n) +{ + return (__force __wsum)n; +} + +#define CSUM_MANGLED_0 ((__force __sum16)0xffff) + +static __always_inline void csum_replace_by_diff(__sum16 *sum, __wsum diff) +{ + *sum = csum_fold(csum_add(diff, ~csum_unfold(*sum))); +} + +static __always_inline void csum_replace4(__sum16 *sum, __be32 from, __be32 to) +{ + __wsum tmp = csum_sub(~csum_unfold(*sum), (__force __wsum)from); + + *sum = csum_fold(csum_add(tmp, (__force __wsum)to)); +} + +/* Implements RFC 1624 (Incremental Internet Checksum) + * 3. Discussion states : + * HC' = ~(~HC + ~m + m') + * m : old value of a 16bit field + * m' : new value of a 16bit field + */ +static __always_inline void csum_replace2(__sum16 *sum, __be16 old, __be16 new) +{ + *sum = ~csum16_add(csum16_sub(~(*sum), old), new); +} + +static inline void csum_replace(__wsum *csum, __wsum old, __wsum new) +{ + *csum = csum_add(csum_sub(*csum, old), new); +} + +static inline unsigned short csum_from32to16(unsigned int sum) +{ + sum += (sum >> 16) | (sum << 16); + return (unsigned short)(sum >> 16); +} + +struct sk_buff; +void inet_proto_csum_replace4(__sum16 *sum, struct sk_buff *skb, + __be32 from, __be32 to, bool pseudohdr); +void inet_proto_csum_replace16(__sum16 *sum, struct sk_buff *skb, + const __be32 *from, const __be32 *to, + bool pseudohdr); +void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb, + __wsum diff, bool pseudohdr, bool ipv6); + +static __always_inline +void inet_proto_csum_replace2(__sum16 *sum, struct sk_buff *skb, + __be16 from, __be16 to, bool pseudohdr) +{ + inet_proto_csum_replace4(sum, skb, (__force __be32)from, + (__force __be32)to, pseudohdr); +} + +static __always_inline __wsum remcsum_adjust(void *ptr, __wsum csum, + int start, int offset) +{ + __sum16 *psum = (__sum16 *)(ptr + offset); + __wsum delta; + + /* Subtract out checksum up to start */ + csum = csum_sub(csum, csum_partial(ptr, start, 0)); + + /* Set derived checksum in packet */ + delta = csum_sub((__force __wsum)csum_fold(csum), + (__force __wsum)*psum); + *psum = csum_fold(csum); + + return delta; +} + +static __always_inline void remcsum_unadjust(__sum16 *psum, __wsum delta) +{ + *psum = csum_fold(csum_sub(delta, (__force __wsum)*psum)); +} + +static __always_inline __wsum wsum_negate(__wsum val) +{ + return (__force __wsum)-((__force u32)val); +} +#endif -- cgit v1.3.1