[PATCH 10/10] dma-mapping: remove dma_virt_ops

From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
	Bernard Metzler <bmt@zurich.ibm.com>,
	Zhu Yanjun <yanjunz@nvidia.com>,
	Logan Gunthorpe <logang@deltatee.com>,
	Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>,
	Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>,
	Santosh Shilimkar <santosh.shilimkar@oracle.com>,
	linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com,
	linux-pci@vger.kernel.org, iommu@lists.linux-foundation.org
Subject: [PATCH 10/10] dma-mapping: remove dma_virt_ops
Date: Fri,  6 Nov 2020 19:19:41 +0100	[thread overview]
Message-ID: <20201106181941.1878556-11-hch@lst.de> (raw)
In-Reply-To: <20201106181941.1878556-1-hch@lst.de>

Now that the RDMA core deals with devices that only do DMA mapping in
lower layers properly, there is no user for dma_virt_ops and it can
be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/dma-mapping.h |  2 --
 kernel/dma/Kconfig          |  5 ---
 kernel/dma/Makefile         |  1 -
 kernel/dma/virt.c           | 61 -------------------------------------
 4 files changed, 69 deletions(-)
 delete mode 100644 kernel/dma/virt.c

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 956151052d4542..2aaed35b556df4 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -565,6 +565,4 @@ static inline int dma_mmap_wc(struct device *dev,
 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
 		dma_addr_t dma_start, u64 size);
 
-extern const struct dma_map_ops dma_virt_ops;
-
 #endif /* _LINUX_DMA_MAPPING_H */
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index c99de4a2145889..fd2db2665fc691 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -75,11 +75,6 @@ config ARCH_HAS_DMA_PREP_COHERENT
 config ARCH_HAS_FORCE_DMA_UNENCRYPTED
 	bool
 
-config DMA_VIRT_OPS
-	bool
-	depends on HAS_DMA
-	select DMA_OPS
-
 config SWIOTLB
 	bool
 	select NEED_DMA_MAP_STATE
diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile
index dc755ab68aabf9..cd1d86358a7a62 100644
--- a/kernel/dma/Makefile
+++ b/kernel/dma/Makefile
@@ -5,7 +5,6 @@ obj-$(CONFIG_DMA_OPS)			+= ops_helpers.o
 obj-$(CONFIG_DMA_OPS)			+= dummy.o
 obj-$(CONFIG_DMA_CMA)			+= contiguous.o
 obj-$(CONFIG_DMA_DECLARE_COHERENT)	+= coherent.o
-obj-$(CONFIG_DMA_VIRT_OPS)		+= virt.o
 obj-$(CONFIG_DMA_API_DEBUG)		+= debug.o
 obj-$(CONFIG_SWIOTLB)			+= swiotlb.o
 obj-$(CONFIG_DMA_COHERENT_POOL)		+= pool.o
diff --git a/kernel/dma/virt.c b/kernel/dma/virt.c
deleted file mode 100644
index 59d32317dd574a..00000000000000
--- a/kernel/dma/virt.c
+++ /dev/null
@@ -1,61 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * DMA operations that map to virtual addresses without flushing memory.
- */
-#include <linux/export.h>
-#include <linux/mm.h>
-#include <linux/dma-map-ops.h>
-#include <linux/scatterlist.h>
-
-static void *dma_virt_alloc(struct device *dev, size_t size,
-			    dma_addr_t *dma_handle, gfp_t gfp,
-			    unsigned long attrs)
-{
-	void *ret;
-
-	ret = (void *)__get_free_pages(gfp | __GFP_ZERO, get_order(size));
-	if (ret)
-		*dma_handle = (uintptr_t)ret;
-	return ret;
-}
-
-static void dma_virt_free(struct device *dev, size_t size,
-			  void *cpu_addr, dma_addr_t dma_addr,
-			  unsigned long attrs)
-{
-	free_pages((unsigned long)cpu_addr, get_order(size));
-}
-
-static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page,
-				    unsigned long offset, size_t size,
-				    enum dma_data_direction dir,
-				    unsigned long attrs)
-{
-	return (uintptr_t)(page_address(page) + offset);
-}
-
-static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl,
-			   int nents, enum dma_data_direction dir,
-			   unsigned long attrs)
-{
-	int i;
-	struct scatterlist *sg;
-
-	for_each_sg(sgl, sg, nents, i) {
-		BUG_ON(!sg_page(sg));
-		sg_dma_address(sg) = (uintptr_t)sg_virt(sg);
-		sg_dma_len(sg) = sg->length;
-	}
-
-	return nents;
-}
-
-const struct dma_map_ops dma_virt_ops = {
-	.alloc			= dma_virt_alloc,
-	.free			= dma_virt_free,
-	.map_page		= dma_virt_map_page,
-	.map_sg			= dma_virt_map_sg,
-	.alloc_pages		= dma_common_alloc_pages,
-	.free_pages		= dma_common_free_pages,
-};
-EXPORT_SYMBOL(dma_virt_ops);
-- 
2.28.0

