linux-kernel - [PATCH v5 06/14] dma-mapping: remove unused mapping resource callbacks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251015-remove-map-page-v5-6-3bbfe3a25cdf@kernel.org>
Date: Wed, 15 Oct 2025 12:12:52 +0300
From: Leon Romanovsky <leon@...nel.org>
To: Marek Szyprowski <m.szyprowski@...sung.com>,
	Robin Murphy <robin.murphy@....com>,
	Russell King <linux@...linux.org.uk>,
	Juergen Gross <jgross@...e.com>,
	Stefano Stabellini <sstabellini@...nel.org>,
	Oleksandr Tyshchenko <oleksandr_tyshchenko@...m.com>,
	Richard Henderson <richard.henderson@...aro.org>,
	Matt Turner <mattst88@...il.com>,
	Thomas Bogendoerfer <tsbogend@...ha.franken.de>,
	"James E.J. Bottomley" <James.Bottomley@...senPartnership.com>,
	Helge Deller <deller@....de>,
	Madhavan Srinivasan <maddy@...ux.ibm.com>,
	Michael Ellerman <mpe@...erman.id.au>,
	Nicholas Piggin <npiggin@...il.com>,
	Christophe Leroy <christophe.leroy@...roup.eu>,
	Geoff Levand <geoff@...radead.org>,
	"David S. Miller" <davem@...emloft.net>,
	Andreas Larsson <andreas@...sler.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	x86@...nel.org,
	"H. Peter Anvin" <hpa@...or.com>
Cc: iommu@...ts.linux.dev,
	linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	xen-devel@...ts.xenproject.org,
	linux-alpha@...r.kernel.org,
	linux-mips@...r.kernel.org,
	linux-parisc@...r.kernel.org,
	linuxppc-dev@...ts.ozlabs.org,
	sparclinux@...r.kernel.org,
	Jason Gunthorpe <jgg@...pe.ca>,
	Jason Gunthorpe <jgg@...dia.com>
Subject: [PATCH v5 06/14] dma-mapping: remove unused mapping resource callbacks

From: Leon Romanovsky <leonro@...dia.com>

After ARM and XEN conversions to use physical addresses for the mapping,
there are no in-kernel users for map_resource/unmap_resource callbacks,
so remove them.

Reviewed-by: Jason Gunthorpe <jgg@...dia.com>
Signed-off-by: Leon Romanovsky <leonro@...dia.com>
---
 include/linux/dma-map-ops.h |  6 ------
 kernel/dma/mapping.c        | 16 ++++------------
 2 files changed, 4 insertions(+), 18 deletions(-)

diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 79d2a74d4b49..2e98ecc313a3 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -53,12 +53,6 @@ struct dma_map_ops {
 			enum dma_data_direction dir, unsigned long attrs);
 	void (*unmap_sg)(struct device *dev, struct scatterlist *sg, int nents,
 			enum dma_data_direction dir, unsigned long attrs);
-	dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr,
-			size_t size, enum dma_data_direction dir,
-			unsigned long attrs);
-	void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle,
-			size_t size, enum dma_data_direction dir,
-			unsigned long attrs);
 	void (*sync_single_for_cpu)(struct device *dev, dma_addr_t dma_handle,
 			size_t size, enum dma_data_direction dir);
 	void (*sync_single_for_device)(struct device *dev,
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 4080aebe5deb..32a85bfdf873 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -157,7 +157,7 @@ dma_addr_t dma_map_phys(struct device *dev, phys_addr_t phys, size_t size,
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 	bool is_mmio = attrs & DMA_ATTR_MMIO;
-	dma_addr_t addr;
+	dma_addr_t addr = DMA_MAPPING_ERROR;
 
 	BUG_ON(!valid_dma_direction(dir));
 
@@ -171,18 +171,13 @@ dma_addr_t dma_map_phys(struct device *dev, phys_addr_t phys, size_t size,
 		addr = iommu_dma_map_phys(dev, phys, size, dir, attrs);
 	else if (ops->map_phys)
 		addr = ops->map_phys(dev, phys, size, dir, attrs);
-	else if (is_mmio) {
-		if (!ops->map_resource)
-			return DMA_MAPPING_ERROR;
-
-		addr = ops->map_resource(dev, phys, size, dir, attrs);
-	} else {
+	else if (!is_mmio && ops->map_page) {
 		struct page *page = phys_to_page(phys);
 		size_t offset = offset_in_page(phys);
 
 		/*
 		 * The dma_ops API contract for ops->map_page() requires
-		 * kmappable memory, while ops->map_resource() does not.
+		 * kmappable memory.
 		 */
 		addr = ops->map_page(dev, page, offset, size, dir, attrs);
 	}
@@ -227,10 +222,7 @@ void dma_unmap_phys(struct device *dev, dma_addr_t addr, size_t size,
 		iommu_dma_unmap_phys(dev, addr, size, dir, attrs);
 	else if (ops->unmap_phys)
 		ops->unmap_phys(dev, addr, size, dir, attrs);
-	else if (is_mmio) {
-		if (ops->unmap_resource)
-			ops->unmap_resource(dev, addr, size, dir, attrs);
-	} else
+	else
 		ops->unmap_page(dev, addr, size, dir, attrs);
 	trace_dma_unmap_phys(dev, addr, size, dir, attrs);
 	debug_dma_unmap_phys(dev, addr, size, dir);

-- 
2.51.0