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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 454C5C3DA4A for ; Fri, 2 Aug 2024 09:38:11 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4Wb13P52yKz3dwr for ; Fri, 2 Aug 2024 19:38:09 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=2604:1380:4641:c500::1; helo=dfw.source.kernel.org; envelope-from=cmarinas@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4Wb12x6xVQz3cVR for ; Fri, 2 Aug 2024 19:37:45 +1000 (AEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id F0D3561446; Fri, 2 Aug 2024 09:37:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C709C32782; Fri, 2 Aug 2024 09:37:41 +0000 (UTC) Date: Fri, 2 Aug 2024 10:37:38 +0100 From: Catalin Marinas To: Baruch Siach Subject: Re: [PATCH v5 2/3] dma: replace zone_dma_bits by zone_dma_limit Message-ID: References: <5821a1b2eb82847ccbac0945da040518d6f6f16b.1722578375.git.baruch@tkos.co.il> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5821a1b2eb82847ccbac0945da040518d6f6f16b.1722578375.git.baruch@tkos.co.il> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-s390@vger.kernel.org, Ramon Fried , Petr =?utf-8?B?VGVzYcWZw61r?= , Will Deacon , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, Elad Nachman , Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Marek Szyprowski Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Fri, Aug 02, 2024 at 09:03:47AM +0300, Baruch Siach wrote: > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 3b4be4ca3b08..62b36fda44c9 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -20,7 +20,7 @@ > * it for entirely different regions. In that case the arch code needs to > * override the variable below for dma-direct to work properly. > */ > -unsigned int zone_dma_bits __ro_after_init = 24; > +u64 zone_dma_limit __ro_after_init = DMA_BIT_MASK(24); u64 here makes sense even if it may be larger than phys_addr_t. It matches the phys_limit type in the swiotlb code. The compilers should no longer complain. > diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c > index d10613eb0f63..7b04f7575796 100644 > --- a/kernel/dma/pool.c > +++ b/kernel/dma/pool.c > @@ -70,9 +70,9 @@ static bool cma_in_zone(gfp_t gfp) > /* CMA can't cross zone boundaries, see cma_activate_area() */ > end = cma_get_base(cma) + size - 1; > if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA)) > - return end <= DMA_BIT_MASK(zone_dma_bits); > + return end <= zone_dma_limit; > if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32)) > - return end <= DMA_BIT_MASK(32); > + return end <= max(DMA_BIT_MASK(32), zone_dma_limit); > return true; > } > > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index 043b0ecd3e8d..bb51bd5335ad 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -450,9 +450,9 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask, > if (!remap) > io_tlb_default_mem.can_grow = true; > if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp_mask & __GFP_DMA)) > - io_tlb_default_mem.phys_limit = DMA_BIT_MASK(zone_dma_bits); > + io_tlb_default_mem.phys_limit = zone_dma_limit; > else if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp_mask & __GFP_DMA32)) > - io_tlb_default_mem.phys_limit = DMA_BIT_MASK(32); > + io_tlb_default_mem.phys_limit = max(DMA_BIT_MASK(32), zone_dma_limit); > else > io_tlb_default_mem.phys_limit = virt_to_phys(high_memory - 1); > #endif These two look correct to me now and it's the least intrusive (the alternative would have been a zone_dma32_limit). The arch code, however, needs to ensure that zone_dma_limit can always support 32-bit devices even if it is above 4GB (with the relevant dma offsets in place for such devices). -- Catalin