Revision 0432a0a066b05361b6d4d26522233c3c76c9e5da authored by Linus Torvalds on 03 August 2019, 17:51:29 UTC, committed by Linus Torvalds on 03 August 2019, 17:51:29 UTC
Pull vdso timer fixes from Thomas Gleixner:
 "A series of commits to deal with the regression caused by the generic
  VDSO implementation.

  The usage of clock_gettime64() for 32bit compat fallback syscalls
  caused seccomp filters to kill innocent processes because they only
  allow clock_gettime().

  Handle the compat syscalls with clock_gettime() as before, which is
  not a functional problem for the VDSO as the legacy compat application
  interface is not y2038 safe anyway. It's just extra fallback code
  which needs to be implemented on every architecture.

  It's opt in for now so that it does not break the compile of already
  converted architectures in linux-next. Once these are fixed, the
  #ifdeffery goes away.

  So much for trying to be smart and reuse code..."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  arm64: compat: vdso: Use legacy syscalls as fallback
  x86/vdso/32: Use 32bit syscall fallback
  lib/vdso/32: Provide legacy syscall fallbacks
  lib/vdso: Move fallback invocation to the callers
  lib/vdso/32: Remove inconsistent NULL pointer checks
2 parent s af42e74 + 33a5898
Raw File
xxhash.c
/*
 * xxHash - Extremely Fast Hash algorithm
 * Copyright (C) 2012-2016, Yann Collet.
 *
 * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following disclaimer
 *     in the documentation and/or other materials provided with the
 *     distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 2 as published by the
 * Free Software Foundation. This program is dual-licensed; you may select
 * either version 2 of the GNU General Public License ("GPL") or BSD license
 * ("BSD").
 *
 * You can contact the author at:
 * - xxHash homepage: http://cyan4973.github.io/xxHash/
 * - xxHash source repository: https://github.com/Cyan4973/xxHash
 */

#include <asm/unaligned.h>
#include <linux/errno.h>
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/xxhash.h>

/*-*************************************
 * Macros
 **************************************/
#define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r)))
#define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r)))

#ifdef __LITTLE_ENDIAN
# define XXH_CPU_LITTLE_ENDIAN 1
#else
# define XXH_CPU_LITTLE_ENDIAN 0
#endif

/*-*************************************
 * Constants
 **************************************/
static const uint32_t PRIME32_1 = 2654435761U;
static const uint32_t PRIME32_2 = 2246822519U;
static const uint32_t PRIME32_3 = 3266489917U;
static const uint32_t PRIME32_4 =  668265263U;
static const uint32_t PRIME32_5 =  374761393U;

static const uint64_t PRIME64_1 = 11400714785074694791ULL;
static const uint64_t PRIME64_2 = 14029467366897019727ULL;
static const uint64_t PRIME64_3 =  1609587929392839161ULL;
static const uint64_t PRIME64_4 =  9650029242287828579ULL;
static const uint64_t PRIME64_5 =  2870177450012600261ULL;

/*-**************************
 *  Utils
 ***************************/
void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src)
{
	memcpy(dst, src, sizeof(*dst));
}
EXPORT_SYMBOL(xxh32_copy_state);

void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src)
{
	memcpy(dst, src, sizeof(*dst));
}
EXPORT_SYMBOL(xxh64_copy_state);

/*-***************************
 * Simple Hash Functions
 ****************************/
static uint32_t xxh32_round(uint32_t seed, const uint32_t input)
{
	seed += input * PRIME32_2;
	seed = xxh_rotl32(seed, 13);
	seed *= PRIME32_1;
	return seed;
}

uint32_t xxh32(const void *input, const size_t len, const uint32_t seed)
{
	const uint8_t *p = (const uint8_t *)input;
	const uint8_t *b_end = p + len;
	uint32_t h32;

	if (len >= 16) {
		const uint8_t *const limit = b_end - 16;
		uint32_t v1 = seed + PRIME32_1 + PRIME32_2;
		uint32_t v2 = seed + PRIME32_2;
		uint32_t v3 = seed + 0;
		uint32_t v4 = seed - PRIME32_1;

		do {
			v1 = xxh32_round(v1, get_unaligned_le32(p));
			p += 4;
			v2 = xxh32_round(v2, get_unaligned_le32(p));
			p += 4;
			v3 = xxh32_round(v3, get_unaligned_le32(p));
			p += 4;
			v4 = xxh32_round(v4, get_unaligned_le32(p));
			p += 4;
		} while (p <= limit);

		h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) +
			xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18);
	} else {
		h32 = seed + PRIME32_5;
	}

	h32 += (uint32_t)len;

	while (p + 4 <= b_end) {
		h32 += get_unaligned_le32(p) * PRIME32_3;
		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
		p += 4;
	}

	while (p < b_end) {
		h32 += (*p) * PRIME32_5;
		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
		p++;
	}

	h32 ^= h32 >> 15;
	h32 *= PRIME32_2;
	h32 ^= h32 >> 13;
	h32 *= PRIME32_3;
	h32 ^= h32 >> 16;

	return h32;
}
EXPORT_SYMBOL(xxh32);

static uint64_t xxh64_round(uint64_t acc, const uint64_t input)
{
	acc += input * PRIME64_2;
	acc = xxh_rotl64(acc, 31);
	acc *= PRIME64_1;
	return acc;
}

static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val)
{
	val = xxh64_round(0, val);
	acc ^= val;
	acc = acc * PRIME64_1 + PRIME64_4;
	return acc;
}

uint64_t xxh64(const void *input, const size_t len, const uint64_t seed)
{
	const uint8_t *p = (const uint8_t *)input;
	const uint8_t *const b_end = p + len;
	uint64_t h64;

	if (len >= 32) {
		const uint8_t *const limit = b_end - 32;
		uint64_t v1 = seed + PRIME64_1 + PRIME64_2;
		uint64_t v2 = seed + PRIME64_2;
		uint64_t v3 = seed + 0;
		uint64_t v4 = seed - PRIME64_1;

		do {
			v1 = xxh64_round(v1, get_unaligned_le64(p));
			p += 8;
			v2 = xxh64_round(v2, get_unaligned_le64(p));
			p += 8;
			v3 = xxh64_round(v3, get_unaligned_le64(p));
			p += 8;
			v4 = xxh64_round(v4, get_unaligned_le64(p));
			p += 8;
		} while (p <= limit);

		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
		h64 = xxh64_merge_round(h64, v1);
		h64 = xxh64_merge_round(h64, v2);
		h64 = xxh64_merge_round(h64, v3);
		h64 = xxh64_merge_round(h64, v4);

	} else {
		h64  = seed + PRIME64_5;
	}

	h64 += (uint64_t)len;

	while (p + 8 <= b_end) {
		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));

		h64 ^= k1;
		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
		p += 8;
	}

	if (p + 4 <= b_end) {
		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
		p += 4;
	}

	while (p < b_end) {
		h64 ^= (*p) * PRIME64_5;
		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
		p++;
	}

	h64 ^= h64 >> 33;
	h64 *= PRIME64_2;
	h64 ^= h64 >> 29;
	h64 *= PRIME64_3;
	h64 ^= h64 >> 32;

	return h64;
}
EXPORT_SYMBOL(xxh64);

/*-**************************************************
 * Advanced Hash Functions
 ***************************************************/
void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed)
{
	/* use a local state for memcpy() to avoid strict-aliasing warnings */
	struct xxh32_state state;

	memset(&state, 0, sizeof(state));
	state.v1 = seed + PRIME32_1 + PRIME32_2;
	state.v2 = seed + PRIME32_2;
	state.v3 = seed + 0;
	state.v4 = seed - PRIME32_1;
	memcpy(statePtr, &state, sizeof(state));
}
EXPORT_SYMBOL(xxh32_reset);

void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
{
	/* use a local state for memcpy() to avoid strict-aliasing warnings */
	struct xxh64_state state;

	memset(&state, 0, sizeof(state));
	state.v1 = seed + PRIME64_1 + PRIME64_2;
	state.v2 = seed + PRIME64_2;
	state.v3 = seed + 0;
	state.v4 = seed - PRIME64_1;
	memcpy(statePtr, &state, sizeof(state));
}
EXPORT_SYMBOL(xxh64_reset);

int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
{
	const uint8_t *p = (const uint8_t *)input;
	const uint8_t *const b_end = p + len;

	if (input == NULL)
		return -EINVAL;

	state->total_len_32 += (uint32_t)len;
	state->large_len |= (len >= 16) | (state->total_len_32 >= 16);

	if (state->memsize + len < 16) { /* fill in tmp buffer */
		memcpy((uint8_t *)(state->mem32) + state->memsize, input, len);
		state->memsize += (uint32_t)len;
		return 0;
	}

	if (state->memsize) { /* some data left from previous update */
		const uint32_t *p32 = state->mem32;

		memcpy((uint8_t *)(state->mem32) + state->memsize, input,
			16 - state->memsize);

		state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32));
		p32++;
		state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32));
		p32++;
		state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32));
		p32++;
		state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32));
		p32++;

		p += 16-state->memsize;
		state->memsize = 0;
	}

	if (p <= b_end - 16) {
		const uint8_t *const limit = b_end - 16;
		uint32_t v1 = state->v1;
		uint32_t v2 = state->v2;
		uint32_t v3 = state->v3;
		uint32_t v4 = state->v4;

		do {
			v1 = xxh32_round(v1, get_unaligned_le32(p));
			p += 4;
			v2 = xxh32_round(v2, get_unaligned_le32(p));
			p += 4;
			v3 = xxh32_round(v3, get_unaligned_le32(p));
			p += 4;
			v4 = xxh32_round(v4, get_unaligned_le32(p));
			p += 4;
		} while (p <= limit);

		state->v1 = v1;
		state->v2 = v2;
		state->v3 = v3;
		state->v4 = v4;
	}

	if (p < b_end) {
		memcpy(state->mem32, p, (size_t)(b_end-p));
		state->memsize = (uint32_t)(b_end-p);
	}

	return 0;
}
EXPORT_SYMBOL(xxh32_update);

uint32_t xxh32_digest(const struct xxh32_state *state)
{
	const uint8_t *p = (const uint8_t *)state->mem32;
	const uint8_t *const b_end = (const uint8_t *)(state->mem32) +
		state->memsize;
	uint32_t h32;

	if (state->large_len) {
		h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) +
			xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18);
	} else {
		h32 = state->v3 /* == seed */ + PRIME32_5;
	}

	h32 += state->total_len_32;

	while (p + 4 <= b_end) {
		h32 += get_unaligned_le32(p) * PRIME32_3;
		h32 = xxh_rotl32(h32, 17) * PRIME32_4;
		p += 4;
	}

	while (p < b_end) {
		h32 += (*p) * PRIME32_5;
		h32 = xxh_rotl32(h32, 11) * PRIME32_1;
		p++;
	}

	h32 ^= h32 >> 15;
	h32 *= PRIME32_2;
	h32 ^= h32 >> 13;
	h32 *= PRIME32_3;
	h32 ^= h32 >> 16;

	return h32;
}
EXPORT_SYMBOL(xxh32_digest);

int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
{
	const uint8_t *p = (const uint8_t *)input;
	const uint8_t *const b_end = p + len;

	if (input == NULL)
		return -EINVAL;

	state->total_len += len;

	if (state->memsize + len < 32) { /* fill in tmp buffer */
		memcpy(((uint8_t *)state->mem64) + state->memsize, input, len);
		state->memsize += (uint32_t)len;
		return 0;
	}

	if (state->memsize) { /* tmp buffer is full */
		uint64_t *p64 = state->mem64;

		memcpy(((uint8_t *)p64) + state->memsize, input,
			32 - state->memsize);

		state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64));
		p64++;
		state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64));
		p64++;
		state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64));
		p64++;
		state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64));

		p += 32 - state->memsize;
		state->memsize = 0;
	}

	if (p + 32 <= b_end) {
		const uint8_t *const limit = b_end - 32;
		uint64_t v1 = state->v1;
		uint64_t v2 = state->v2;
		uint64_t v3 = state->v3;
		uint64_t v4 = state->v4;

		do {
			v1 = xxh64_round(v1, get_unaligned_le64(p));
			p += 8;
			v2 = xxh64_round(v2, get_unaligned_le64(p));
			p += 8;
			v3 = xxh64_round(v3, get_unaligned_le64(p));
			p += 8;
			v4 = xxh64_round(v4, get_unaligned_le64(p));
			p += 8;
		} while (p <= limit);

		state->v1 = v1;
		state->v2 = v2;
		state->v3 = v3;
		state->v4 = v4;
	}

	if (p < b_end) {
		memcpy(state->mem64, p, (size_t)(b_end-p));
		state->memsize = (uint32_t)(b_end - p);
	}

	return 0;
}
EXPORT_SYMBOL(xxh64_update);

uint64_t xxh64_digest(const struct xxh64_state *state)
{
	const uint8_t *p = (const uint8_t *)state->mem64;
	const uint8_t *const b_end = (const uint8_t *)state->mem64 +
		state->memsize;
	uint64_t h64;

	if (state->total_len >= 32) {
		const uint64_t v1 = state->v1;
		const uint64_t v2 = state->v2;
		const uint64_t v3 = state->v3;
		const uint64_t v4 = state->v4;

		h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) +
			xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18);
		h64 = xxh64_merge_round(h64, v1);
		h64 = xxh64_merge_round(h64, v2);
		h64 = xxh64_merge_round(h64, v3);
		h64 = xxh64_merge_round(h64, v4);
	} else {
		h64  = state->v3 + PRIME64_5;
	}

	h64 += (uint64_t)state->total_len;

	while (p + 8 <= b_end) {
		const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p));

		h64 ^= k1;
		h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4;
		p += 8;
	}

	if (p + 4 <= b_end) {
		h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1;
		h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
		p += 4;
	}

	while (p < b_end) {
		h64 ^= (*p) * PRIME64_5;
		h64 = xxh_rotl64(h64, 11) * PRIME64_1;
		p++;
	}

	h64 ^= h64 >> 33;
	h64 *= PRIME64_2;
	h64 ^= h64 >> 29;
	h64 *= PRIME64_3;
	h64 ^= h64 >> 32;

	return h64;
}
EXPORT_SYMBOL(xxh64_digest);

MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("xxHash");
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