lib/crypto: chacha: Consolidate into single module

2025-08-29T16:50:19+00:00

Consolidate the ChaCha code into a single module (excluding chacha-block-generic.c which remains always built-in for random.c), similar to various other algorithms: - Each arch now provides a header file lib/crypto/$(SRCARCH)/chacha.h, replacing lib/crypto/$(SRCARCH)/chacha*.c. The header defines chacha_crypt_arch() and hchacha_block_arch(). It is included by lib/crypto/chacha.c, and thus the code gets built into the single libchacha module, with improved inlining in some cases. - Whether arch-optimized ChaCha is buildable is now controlled centrally by lib/crypto/Kconfig instead of by lib/crypto/$(SRCARCH)/Kconfig. The conditions for enabling it remain the same as before, and it remains enabled by default. - Any additional arch-specific translation units for the optimized ChaCha code, such as assembly files, are now compiled by lib/crypto/Makefile instead of lib/crypto/$(SRCARCH)/Makefile. This removes the last use for the Makefile and Kconfig files in the arm64, mips, powerpc, riscv, and s390 subdirectories of lib/crypto/. So also remove those files and the references to them. Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250827151131.27733-7-ebiggers@kernel.org Signed-off-by: Eric Biggers

lwn.git/lib/crypto/riscv/chacha.h, branch master

lib/crypto: chacha: Consolidate into single module