dma-mapping: remove dma_virt_ops

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.

Link: https://lore.kernel.org/r/20201106181941.1878556-11-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 9561510..2aaed35 100644 (file)
--- 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 c99de4a..fd2db26 100644 (file)
--- 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 dc755ab..cd1d863 100644 (file)
--- 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 (file)
index 59d3231..0000000
--- 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);