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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA011CD5BAC for ; Thu, 21 May 2026 15:38:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=Qomyt6SRN6loAiKuzG+mnZMN+9NDAav5uB2vD7COXYY=; b=YQZGzTR5T+E1tsIOhR8VcRnhgn xa3/pwbIVCiIr0yjbb1OloC9cL7lB3HARzinqmpiw6rGzAVQbbWzt6245VjulsCYvbCbUXpyAG6vj kzsEsxShRc0ncupSzWbcTKeHmRlon0vkPIAKjZXNdRZ4WQmUCOrAxVBBYrQIXZkv4llh03Q+jCjFG 0bwgOdPZXvK4qw/sIGpkIhCwtAxQmAiq7+AQWzcDIlNKwjl4/6TnQD/x1VZkAWViHmAA1Phcd47HD O0cK9fiL6ArmfYDy6NumKaY/9NlCXzxjlG7eER/5pjKoYpZtURz6KBpkTMDyR1txUVZ2fpjSYjIth CJAVEtrg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wQ5TK-00000008LpL-2bPt; Thu, 21 May 2026 15:38:06 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wQ5TH-00000008Lnl-2Z3S for linux-arm-kernel@lists.infradead.org; Thu, 21 May 2026 15:38:05 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 1FFBF44148; Thu, 21 May 2026 15:38:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 055241F000E9; Thu, 21 May 2026 15:37:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779377883; bh=Qomyt6SRN6loAiKuzG+mnZMN+9NDAav5uB2vD7COXYY=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=SKjGQCP1jUHZn8lGcvNb16fhytEsPovJvUrNUllKBoXBnYhKzZyiWFp5SXoR00qSh 4Yi1RUq4BpLuoEGXd/ZfpfHeWAgR0+SKGaVyCv/OICsvCL8QuRGyjiXEjI5giDln+y nPHP27gGY79//Ncb34+zHprzV63ewWoOHLFrps3BSWb2kqL1XebtXJJN3TVZe3EV/k urWUK7qq4xQ19I8ijQAMN6p1ereVXTWRx1/nsAg3dl09jZhyb9oK04vIX/Z5RdNTgn 97oMJkfi8HsdKYrcl3kj4rpuwHeCO8ecnTXfnja7vDYtRCrTlYPo8c5gdohMtv0jZ2 UZTZ7iyYKVbCg== X-Mailer: emacs 30.2 (via feedmail 11-beta-1 I) From: Aneesh Kumar K.V To: iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev Cc: Robin Murphy , Marek Szyprowski , Will Deacon , Marc Zyngier , Steven Price , Suzuki K Poulose , Catalin Marinas , Jiri Pirko , Jason Gunthorpe , Mostafa Saleh , Petr Tesarik , Alexey Kardashevskiy , Dan Williams , Xu Yilun , linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , x86@kernel.org Subject: Re: [PATCH v4 07/13] dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED In-Reply-To: <20260512090408.794195-8-aneesh.kumar@kernel.org> References: <20260512090408.794195-1-aneesh.kumar@kernel.org> <20260512090408.794195-8-aneesh.kumar@kernel.org> Date: Thu, 21 May 2026 21:07:49 +0530 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260521_083803_697020_B0F4B0C2 X-CRM114-Status: GOOD ( 16.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org "Aneesh Kumar K.V (Arm)" writes: > diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h > index e05dc7649366..4e35264ab6f8 100644 > --- a/kernel/dma/direct.h > +++ b/kernel/dma/direct.h > @@ -89,36 +89,32 @@ static inline dma_addr_t dma_direct_map_phys(struct device *dev, > dma_addr_t dma_addr; > > if (is_swiotlb_force_bounce(dev)) { > - if (!(attrs & DMA_ATTR_CC_SHARED)) { > - if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) > - return DMA_MAPPING_ERROR; > + if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) > + return DMA_MAPPING_ERROR; > > - return swiotlb_map(dev, phys, size, dir, attrs); > - } > - } else if (attrs & DMA_ATTR_CC_SHARED) { > - return DMA_MAPPING_ERROR; > + return swiotlb_map(dev, phys, size, dir, attrs); > } > > - if (attrs & DMA_ATTR_MMIO) { > - dma_addr = phys; > - if (unlikely(!dma_capable(dev, dma_addr, size, false, attrs))) > - goto err_overflow; > - } else if (attrs & DMA_ATTR_CC_SHARED) { > + if (attrs & DMA_ATTR_CC_SHARED) > dma_addr = phys_to_dma_unencrypted(dev, phys); > + else > + dma_addr = phys_to_dma_encrypted(dev, phys); > + > + if (attrs & DMA_ATTR_MMIO) { > if (unlikely(!dma_capable(dev, dma_addr, size, false, attrs))) > goto err_overflow; > - } else { > - dma_addr = phys_to_dma(dev, phys); > - if (unlikely(!dma_capable(dev, dma_addr, size, true, attrs)) || > - dma_kmalloc_needs_bounce(dev, size, dir)) { > - if (is_swiotlb_active(dev) && > - !(attrs & DMA_ATTR_REQUIRE_COHERENT)) > - return swiotlb_map(dev, phys, size, dir, attrs); > + goto dma_mapped; > + } > > - goto err_overflow; > - } > + if (unlikely(!dma_capable(dev, dma_addr, size, true, attrs)) || > + dma_kmalloc_needs_bounce(dev, size, dir)) { > + if (is_swiotlb_active(dev) && > + !(attrs & DMA_ATTR_REQUIRE_COHERENT)) > + return swiotlb_map(dev, phys, size, dir, attrs); > + goto err_overflow; > } > > +dma_mapped: > if (!dev_is_dma_coherent(dev) && > !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) { > arch_sync_dma_for_device(phys, size, dir); > -- > 2.43.0 I guess we need this change on top of the above modified kernel/dma/direct.h @@ -88,6 +88,13 @@ static inline dma_addr_t dma_direct_map_phys(struct device *dev, { dma_addr_t dma_addr; + /* + * For a device requiring unencrypted DMA, MMIO memory is treated + * as shared by default. + */ + if (force_dma_unencrypted(dev) && (attrs & DMA_ATTR_MMIO)) + attrs |= DMA_ATTR_CC_SHARED; + if (is_swiotlb_force_bounce(dev)) { if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) return DMA_MAPPING_ERROR;