From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- lib/crypto/chacha.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 lib/crypto/chacha.c (limited to 'lib/crypto/chacha.c') diff --git a/lib/crypto/chacha.c b/lib/crypto/chacha.c new file mode 100644 index 000000000..86e5d382a --- /dev/null +++ b/lib/crypto/chacha.c @@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The ChaCha stream cipher (RFC7539) + * + * Copyright (C) 2015 Martin Willi + */ + +#include +#include +#include +#include +#include + +static void __maybe_unused +chacha_crypt_generic(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) +{ + /* aligned to potentially speed up crypto_xor() */ + u8 stream[CHACHA_BLOCK_SIZE] __aligned(sizeof(long)); + + while (bytes >= CHACHA_BLOCK_SIZE) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, CHACHA_BLOCK_SIZE); + bytes -= CHACHA_BLOCK_SIZE; + dst += CHACHA_BLOCK_SIZE; + src += CHACHA_BLOCK_SIZE; + } + if (bytes) { + chacha_block_generic(state, stream, nrounds); + crypto_xor_cpy(dst, src, stream, bytes); + } +} + +#ifdef CONFIG_CRYPTO_LIB_CHACHA_ARCH +#include "chacha.h" /* $(SRCARCH)/chacha.h */ +#else +#define chacha_crypt_arch chacha_crypt_generic +#define hchacha_block_arch hchacha_block_generic +#endif + +void chacha_crypt(struct chacha_state *state, u8 *dst, const u8 *src, + unsigned int bytes, int nrounds) +{ + chacha_crypt_arch(state, dst, src, bytes, nrounds); +} +EXPORT_SYMBOL_GPL(chacha_crypt); + +void hchacha_block(const struct chacha_state *state, + u32 out[HCHACHA_OUT_WORDS], int nrounds) +{ + hchacha_block_arch(state, out, nrounds); +} +EXPORT_SYMBOL_GPL(hchacha_block); + +#ifdef chacha_mod_init_arch +static int __init chacha_mod_init(void) +{ + chacha_mod_init_arch(); + return 0; +} +subsys_initcall(chacha_mod_init); + +static void __exit chacha_mod_exit(void) +{ +} +module_exit(chacha_mod_exit); +#endif + +MODULE_DESCRIPTION("ChaCha stream cipher (RFC7539)"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1