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 DA765CAC582 for ; Sat, 6 Sep 2025 18:54:01 +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:References:Content-Type: Content-Transfer-Encoding:In-Reply-To:From:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=SihwygswkUbDkI6TEnNcbeL2/U8m9DIalmjgcknmvOM=; b=if55GFuNHL15Z2XcQBwgdA4ndG 3a5YMwYe75vxd31XC8c7OQtvhXg5o0DPbZkLgTIpmQS/kqlsoo4rYtqYhBjdYT9dDk12ZwMu2Ib+W 1kBrw9JrnCwPXJJDbuzE4Xq31IbtyowXaTGLShcawTFrsKbcACfG7/EVTznM7fDhchLElEThv5asO 1h0K+3THyZhEkiP1MVfojKN1LK97s5hhpHxYm956mHbgPB+RdlHDbtXGQTkY7mtPwSdIjm1qGK3m2 6RRvLulO7iTSmF8f4tsPJ+vHihH5QZLRDPBsagqGNhg6JwfA7gUK7DBIszul2qkXctNDSDFkUdeCm QmhZI60w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuy2v-00000008Ixp-3n8R; Sat, 06 Sep 2025 18:53:57 +0000 Received: from mailout2.w1.samsung.com ([210.118.77.12]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuZC9-000000034KQ-26rr for linux-nvme@lists.infradead.org; Fri, 05 Sep 2025 16:21:50 +0000 Received: from eucas1p2.samsung.com (unknown [182.198.249.207]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20250905162148euoutp02604d107873dc75c605be1c2733dda215~ib2qaX6dY1912019120euoutp02_; Fri, 5 Sep 2025 16:21:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20250905162148euoutp02604d107873dc75c605be1c2733dda215~ib2qaX6dY1912019120euoutp02_ DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1757089308; bh=SihwygswkUbDkI6TEnNcbeL2/U8m9DIalmjgcknmvOM=; h=Date:Subject:To:Cc:From:In-Reply-To:References:From; b=TMub8T2AywFu0rH6DpstDybTJowRFDNOBYLDkp6Xzd7qGqwZ8ouj39Pirm529DkBN NnHkZVznzmV8UpKTT429M04YfUlrnl7jwCyuT5my78L0ccVnDyJcAFZshVqjrwHKoZ N2bRFb+07AkY+pQ3ta9ua+sPeKgv85ar3t0gyurM= Received: from eusmtip2.samsung.com (unknown [203.254.199.222]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20250905162147eucas1p221ca4e33b0e6396d02908377c6c5b919~ib2pcEwbH0974409744eucas1p2p; Fri, 5 Sep 2025 16:21:47 +0000 (GMT) Received: from [106.210.134.192] (unknown [106.210.134.192]) by eusmtip2.samsung.com (KnoxPortal) with ESMTPA id 20250905162145eusmtip2342879dbc38ddfe0bbff0062e179f725~ib2nn8yb40979609796eusmtip2i; Fri, 5 Sep 2025 16:21:45 +0000 (GMT) Message-ID: <087e7f3d-1e0d-4efe-822f-72d16d161a60@samsung.com> Date: Fri, 5 Sep 2025 18:21:44 +0200 MIME-Version: 1.0 User-Agent: Betterbird (Windows) Subject: Re: [PATCH v5 07/16] dma-mapping: convert dma_direct_*map_page to be phys_addr_t based To: Leon Romanovsky Cc: Leon Romanovsky , Jason Gunthorpe , Abdiel Janulgue , Alexander Potapenko , Alex Gaynor , Andrew Morton , Christoph Hellwig , Danilo Krummrich , David Hildenbrand , iommu@lists.linux.dev, Jason Wang , Jens Axboe , Joerg Roedel , Jonathan Corbet , Juergen Gross , kasan-dev@googlegroups.com, Keith Busch , linux-block@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-nvme@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-trace-kernel@vger.kernel.org, Madhavan Srinivasan , Masami Hiramatsu , Michael Ellerman , "Michael S. Tsirkin" , Miguel Ojeda , Robin Murphy , rust-for-linux@vger.kernel.org, Sagi Grimberg , Stefano Stabellini , Steven Rostedt , virtualization@lists.linux.dev, Will Deacon , xen-devel@lists.xenproject.org Content-Language: en-US From: Marek Szyprowski In-Reply-To: <6b2f4cb436c98d6342db69e965a5621707b9711f.1756822782.git.leon@kernel.org> Content-Transfer-Encoding: 7bit X-CMS-MailID: 20250905162147eucas1p221ca4e33b0e6396d02908377c6c5b919 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20250902144935eucas1p253de9e94315de54325cc61dea9c76490 X-EPHeader: CA X-CMS-RootMailID: 20250902144935eucas1p253de9e94315de54325cc61dea9c76490 References: <6b2f4cb436c98d6342db69e965a5621707b9711f.1756822782.git.leon@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250905_092149_811192_B6550C81 X-CRM114-Status: GOOD ( 27.83 ) X-Mailman-Approved-At: Sat, 06 Sep 2025 11:45:19 -0700 X-BeenThere: linux-nvme@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-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 02.09.2025 16:48, Leon Romanovsky wrote: > From: Leon Romanovsky > > Convert the DMA direct mapping functions to accept physical addresses > directly instead of page+offset parameters. The functions were already > operating on physical addresses internally, so this change eliminates > the redundant page-to-physical conversion at the API boundary. > > The functions dma_direct_map_page() and dma_direct_unmap_page() are > renamed to dma_direct_map_phys() and dma_direct_unmap_phys() respectively, > with their calling convention changed from (struct page *page, > unsigned long offset) to (phys_addr_t phys). > > Architecture-specific functions arch_dma_map_page_direct() and > arch_dma_unmap_page_direct() are similarly renamed to > arch_dma_map_phys_direct() and arch_dma_unmap_phys_direct(). > > The is_pci_p2pdma_page() checks are replaced with DMA_ATTR_MMIO checks > to allow integration with dma_direct_map_resource and dma_direct_map_phys() > is extended to support MMIO path either. > > Reviewed-by: Jason Gunthorpe > Signed-off-by: Leon Romanovsky > --- > arch/powerpc/kernel/dma-iommu.c | 4 +-- > include/linux/dma-map-ops.h | 8 ++--- > kernel/dma/direct.c | 6 ++-- > kernel/dma/direct.h | 57 +++++++++++++++++++++------------ > kernel/dma/mapping.c | 8 ++--- > 5 files changed, 49 insertions(+), 34 deletions(-) > > diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c > index 4d64a5db50f3..0359ab72cd3b 100644 > --- a/arch/powerpc/kernel/dma-iommu.c > +++ b/arch/powerpc/kernel/dma-iommu.c > @@ -14,7 +14,7 @@ > #define can_map_direct(dev, addr) \ > ((dev)->bus_dma_limit >= phys_to_dma((dev), (addr))) > > -bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr) > +bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr) > { > if (likely(!dev->bus_dma_limit)) > return false; > @@ -24,7 +24,7 @@ bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr) > > #define is_direct_handle(dev, h) ((h) >= (dev)->archdata.dma_offset) > > -bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle) > +bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle) > { > if (likely(!dev->bus_dma_limit)) > return false; > diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h > index f48e5fb88bd5..71f5b3025415 100644 > --- a/include/linux/dma-map-ops.h > +++ b/include/linux/dma-map-ops.h > @@ -392,15 +392,15 @@ void *arch_dma_set_uncached(void *addr, size_t size); > void arch_dma_clear_uncached(void *addr, size_t size); > > #ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT > -bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr); > -bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle); > +bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr); > +bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle); > bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg, > int nents); > bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg, > int nents); > #else > -#define arch_dma_map_page_direct(d, a) (false) > -#define arch_dma_unmap_page_direct(d, a) (false) > +#define arch_dma_map_phys_direct(d, a) (false) > +#define arch_dma_unmap_phys_direct(d, a) (false) > #define arch_dma_map_sg_direct(d, s, n) (false) > #define arch_dma_unmap_sg_direct(d, s, n) (false) > #endif > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 24c359d9c879..fa75e3070073 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -453,7 +453,7 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, > if (sg_dma_is_bus_address(sg)) > sg_dma_unmark_bus_address(sg); > else > - dma_direct_unmap_page(dev, sg->dma_address, > + dma_direct_unmap_phys(dev, sg->dma_address, > sg_dma_len(sg), dir, attrs); > } > } > @@ -476,8 +476,8 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, > */ > break; > case PCI_P2PDMA_MAP_NONE: > - sg->dma_address = dma_direct_map_page(dev, sg_page(sg), > - sg->offset, sg->length, dir, attrs); > + sg->dma_address = dma_direct_map_phys(dev, sg_phys(sg), > + sg->length, dir, attrs); > if (sg->dma_address == DMA_MAPPING_ERROR) { > ret = -EIO; > goto out_unmap; > diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h > index d2c0b7e632fc..3f4792910604 100644 > --- a/kernel/dma/direct.h > +++ b/kernel/dma/direct.h > @@ -80,42 +80,57 @@ static inline void dma_direct_sync_single_for_cpu(struct device *dev, > arch_dma_mark_clean(paddr, size); > } > > -static inline dma_addr_t dma_direct_map_page(struct device *dev, > - struct page *page, unsigned long offset, size_t size, > - enum dma_data_direction dir, unsigned long attrs) > +static inline dma_addr_t dma_direct_map_phys(struct device *dev, > + phys_addr_t phys, size_t size, enum dma_data_direction dir, > + unsigned long attrs) > { > - phys_addr_t phys = page_to_phys(page) + offset; > - dma_addr_t dma_addr = phys_to_dma(dev, phys); > + dma_addr_t dma_addr; > > if (is_swiotlb_force_bounce(dev)) { > - if (is_pci_p2pdma_page(page)) > - return DMA_MAPPING_ERROR; > + if (attrs & DMA_ATTR_MMIO) > + goto err_overflow; > + > return swiotlb_map(dev, phys, size, dir, attrs); > } > > - if (unlikely(!dma_capable(dev, dma_addr, size, true)) || > - dma_kmalloc_needs_bounce(dev, size, dir)) { > - if (is_pci_p2pdma_page(page)) > - return DMA_MAPPING_ERROR; > - if (is_swiotlb_active(dev)) > - return swiotlb_map(dev, phys, size, dir, attrs); > - > - dev_WARN_ONCE(dev, 1, > - "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n", > - &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit); > - return DMA_MAPPING_ERROR; > + if (attrs & DMA_ATTR_MMIO) { > + dma_addr = phys; > + if (unlikely(dma_capable(dev, dma_addr, size, false))) "!dma_capable(dev, dma_addr, size, false)" in the above line. It took me a while to find this after noticing that this patchset breaks booting some of me test systems. > + goto err_overflow; > + } else { > + dma_addr = phys_to_dma(dev, phys); > + if (unlikely(!dma_capable(dev, dma_addr, size, true)) || > + dma_kmalloc_needs_bounce(dev, size, dir)) { > + if (is_swiotlb_active(dev)) > + return swiotlb_map(dev, phys, size, dir, attrs); > + > + goto err_overflow; > + } > } > > - if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) > + if (!dev_is_dma_coherent(dev) && > + !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) > arch_sync_dma_for_device(phys, size, dir); > return dma_addr; > + > +err_overflow: > + dev_WARN_ONCE( > + dev, 1, > + "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n", > + &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit); > + return DMA_MAPPING_ERROR; > } > > -static inline void dma_direct_unmap_page(struct device *dev, dma_addr_t addr, > +static inline void dma_direct_unmap_phys(struct device *dev, dma_addr_t addr, > size_t size, enum dma_data_direction dir, unsigned long attrs) > { > - phys_addr_t phys = dma_to_phys(dev, addr); > + phys_addr_t phys; > + > + if (attrs & DMA_ATTR_MMIO) > + /* nothing to do: uncached and no swiotlb */ > + return; > > + phys = dma_to_phys(dev, addr); > if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) > dma_direct_sync_single_for_cpu(dev, addr, size, dir); > > diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c > index 58482536db9b..80481a873340 100644 > --- a/kernel/dma/mapping.c > +++ b/kernel/dma/mapping.c > @@ -166,8 +166,8 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, > return DMA_MAPPING_ERROR; > > if (dma_map_direct(dev, ops) || > - arch_dma_map_page_direct(dev, phys + size)) > - addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); > + arch_dma_map_phys_direct(dev, phys + size)) > + addr = dma_direct_map_phys(dev, phys, size, dir, attrs); > else if (use_dma_iommu(dev)) > addr = iommu_dma_map_phys(dev, phys, size, dir, attrs); > else > @@ -187,8 +187,8 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, > > BUG_ON(!valid_dma_direction(dir)); > if (dma_map_direct(dev, ops) || > - arch_dma_unmap_page_direct(dev, addr + size)) > - dma_direct_unmap_page(dev, addr, size, dir, attrs); > + arch_dma_unmap_phys_direct(dev, addr + size)) > + dma_direct_unmap_phys(dev, addr, size, dir, attrs); > else if (use_dma_iommu(dev)) > iommu_dma_unmap_phys(dev, addr, size, dir, attrs); > else Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland