From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id CFF4BC433EF for ; Tue, 10 May 2022 17:10:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 490876B0071; Tue, 10 May 2022 13:10:42 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 43EFF6B0073; Tue, 10 May 2022 13:10:42 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 308076B0074; Tue, 10 May 2022 13:10:42 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 226466B0071 for ; Tue, 10 May 2022 13:10:42 -0400 (EDT) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 0306F21B80 for ; Tue, 10 May 2022 17:10:41 +0000 (UTC) X-FDA: 79450472724.08.4C1D6D2 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf20.hostedemail.com (Postfix) with ESMTP id 850861C00A9 for ; Tue, 10 May 2022 17:10:32 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CD4B861811; Tue, 10 May 2022 17:10:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6860C385A6; Tue, 10 May 2022 17:10:37 +0000 (UTC) Date: Tue, 10 May 2022 18:10:34 +0100 From: Catalin Marinas To: Herbert Xu Cc: Ard Biesheuvel , Will Deacon , Marc Zyngier , Arnd Bergmann , Greg Kroah-Hartman , Andrew Morton , Linus Torvalds , Linux Memory Management List , Linux ARM , Linux Kernel Mailing List , "David S. Miller" , Linux Crypto Mailing List Subject: Re: [RFC PATCH 2/7] crypto: api - Add crypto_tfm_ctx_dma Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: 94jir1qsrcr4piq6k4btnjefj6zu61wf X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 850861C00A9 Authentication-Results: imf20.hostedemail.com; dkim=none; spf=pass (imf20.hostedemail.com: domain of cmarinas@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=cmarinas@kernel.org; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none) X-Rspam-User: X-HE-Tag: 1652202632-702880 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Hi Herbert, Thanks for putting this together. On Tue, May 10, 2022 at 07:07:10PM +0800, Herbert Xu wrote: > diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h > index f50c5d1725da5..cdf12e51c53a0 100644 > --- a/include/crypto/algapi.h > +++ b/include/crypto/algapi.h > @@ -189,10 +189,34 @@ static inline void crypto_xor_cpy(u8 *dst, const u8 *src1, const u8 *src2, > } > } > > +static inline void *crypto_tfm_ctx(struct crypto_tfm *tfm) > +{ > + return tfm->__crt_ctx; > +} > + > +static inline void *crypto_tfm_ctx_align(struct crypto_tfm *tfm, > + unsigned int align) > +{ > + if (align <= crypto_tfm_ctx_alignment()) > + align = 1; > + > + return PTR_ALIGN(crypto_tfm_ctx(tfm), align); > +} > + > static inline void *crypto_tfm_ctx_aligned(struct crypto_tfm *tfm) > { > - return PTR_ALIGN(crypto_tfm_ctx(tfm), > - crypto_tfm_alg_alignmask(tfm) + 1); > + return crypto_tfm_ctx_align(tfm, crypto_tfm_alg_alignmask(tfm) + 1); > +} > + > +static inline void *crypto_tfm_ctx_dma(struct crypto_tfm *tfm) > +{ > + unsigned int align = 1; > + > +#ifdef ARCH_DMA_MINALIGN > + align = ARCH_DMA_MINALIGN; > +#endif > + > + return crypto_tfm_ctx_align(tfm, align); > } Is there a case where a driver needs the minimum alignment between ARCH_DMA_MINALIGN and crypto_tfm_alg_alignmask()+1? Maybe for platforms where ARCH_DMA_MINALIGN is 8 (fully coherent) but the device's bus master alignment requirements are higher. My plan is to have ARCH_DMA_MINALIGN always defined but potentially higher than ARCH_KMALLOC_MINALIGN on specific architectures. I think crypto_tfm_ctx_dma() should use ARCH_KMALLOC_MINALIGN (and no #ifdefs) until I get my patches sorted and I'll replace it with ARCH_DMA_MINALIGN once it's defined globally (still no #ifdefs). Currently in mainline it's ARCH_KMALLOC_MINALIGN that gives the static DMA alignment. With the explicit crypto_tfm_ctx_dma(), can CRYPTO_MINALIGN_ATTR be dropped entirely? This may be beneficial in reducing the structure size when no DMA is required. -- Catalin