[PATCH 8/9] dma-mapping: move large parts of to kernel/dma

Christoph Hellwig
2020-09-30T08:56:38Z

Most of the dma_direct symbols should only be used by direct.c and
mapping.c, so move them to kernel/dma. In fact more of dma-direct.h
should eventually move, but that will require more coordination with
other subsystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/dma-direct.h | 106 ---------------------------------
kernel/dma/direct.c | 2 +-
kernel/dma/direct.h | 119 +++++++++++++++++++++++++++++++++++++
kernel/dma/mapping.c | 2 +-
4 files changed, 121 insertions(+), 108 deletions(-)
create mode 100644 kernel/dma/direct.h

diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index 38ed3b55034d50..a2d6640c42c04e 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -120,114 +120,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
void dma_direct_free_pages(struct device *dev, size_t size,
struct page *page, dma_addr_t dma_addr,
enum dma_data_direction dir);
-int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
- void *cpu_addr, dma_addr_t dma_addr, size_t size,
- unsigned long attrs);
-bool dma_direct_can_mmap(struct device *dev);
-int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
- void *cpu_addr, dma_addr_t dma_addr, size_t size,
- unsigned long attrs);
int dma_direct_supported(struct device *dev, u64 mask);
-bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr);
-int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
- enum dma_data_direction dir, unsigned long attrs);
dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
size_t size, enum dma_data_direction dir, unsigned long attrs);
-size_t dma_direct_max_mapping_size(struct device *dev);

-#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
- defined(CONFIG_SWIOTLB)
-void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir);
-#else
-static inline void dma_direct_sync_sg_for_device(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
-}
-#endif
-
-#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
- defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \
- defined(CONFIG_SWIOTLB)
-void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
- int nents, enum dma_data_direction dir, unsigned long attrs);
-void dma_direct_sync_sg_for_cpu(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir);
-#else
-static inline void dma_direct_unmap_sg(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir,
- unsigned long attrs)
-{
-}
-static inline void dma_direct_sync_sg_for_cpu(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
-}
-#endif
-
-static inline void dma_direct_sync_single_for_device(struct device *dev,
- dma_addr_t addr, size_t size, enum dma_data_direction dir)
-{
- phys_addr_t paddr = dma_to_phys(dev, addr);
-
- if (unlikely(is_swiotlb_buffer(paddr)))
- swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_DEVICE);
-
- if (!dev_is_dma_coherent(dev))
- arch_sync_dma_for_device(paddr, size, dir);
-}
-
-static inline void dma_direct_sync_single_for_cpu(struct device *dev,
- dma_addr_t addr, size_t size, enum dma_data_direction dir)
-{
- phys_addr_t paddr = dma_to_phys(dev, addr);
-
- if (!dev_is_dma_coherent(dev)) {
- arch_sync_dma_for_cpu(paddr, size, dir);
- arch_sync_dma_for_cpu_all();
- }
-
- if (unlikely(is_swiotlb_buffer(paddr)))
- swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_CPU);
-
- if (dir == DMA_FROM_DEVICE)
- 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)
-{
- phys_addr_t phys = page_to_phys(page) + offset;
- dma_addr_t dma_addr = phys_to_dma(dev, phys);
-
- if (unlikely(swiotlb_force == SWIOTLB_FORCE))
- return swiotlb_map(dev, phys, size, dir, attrs);
-
- if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
- if (swiotlb_force != SWIOTLB_NO_FORCE)
- 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 (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- arch_sync_dma_for_device(phys, size, dir);
- return dma_addr;
-}
-
-static inline void dma_direct_unmap_page(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);
-
- if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
- dma_direct_sync_single_for_cpu(dev, addr, size, dir);
-
- if (unlikely(is_swiotlb_buffer(phys)))
- swiotlb_tbl_unmap_single(dev, phys, size, size, dir, attrs);
-}
#endif /* _LINUX_DMA_DIRECT_H */
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 87697c86f0b82a..bf9f77623022bb 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -7,13 +7,13 @@
#include <linux/memblock.h> /* for max_pfn */
#include <linux/export.h>
#include <linux/mm.h>
-#include <linux/dma-direct.h>
#include <linux/dma-map-ops.h>
#include <linux/scatterlist.h>
#include <linux/pfn.h>
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
#include <linux/slab.h>
+#include "direct.h"

/*
* Most architectures use ZONE_DMA for the first 16 Megabytes, but some use it
diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h
new file mode 100644
index 00000000000000..b9861557873768
--- /dev/null
+++ b/kernel/dma/direct.h
@@ -0,0 +1,119 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Christoph Hellwig.
+ *
+ * DMA operations that map physical memory directly without using an IOMMU.
+ */
+#ifndef _KERNEL_DMA_DIRECT_H
+#define _KERNEL_DMA_DIRECT_H
+
+#include <linux/dma-direct.h>
+
+int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs);
+bool dma_direct_can_mmap(struct device *dev);
+int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ unsigned long attrs);
+bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr);
+int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
+ enum dma_data_direction dir, unsigned long attrs);
+size_t dma_direct_max_mapping_size(struct device *dev);
+
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
+ defined(CONFIG_SWIOTLB)
+void dma_direct_sync_sg_for_device(struct device *dev, struct scatterlist *sgl,
+ int nents, enum dma_data_direction dir);
+#else
+static inline void dma_direct_sync_sg_for_device(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
+{
+}
+#endif
+
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \
+ defined(CONFIG_SWIOTLB)
+void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
+ int nents, enum dma_data_direction dir, unsigned long attrs);
+void dma_direct_sync_sg_for_cpu(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir);
+#else
+static inline void dma_direct_unmap_sg(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+}
+static inline void dma_direct_sync_sg_for_cpu(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
+{
+}
+#endif
+
+static inline void dma_direct_sync_single_for_device(struct device *dev,
+ dma_addr_t addr, size_t size, enum dma_data_direction dir)
+{
+ phys_addr_t paddr = dma_to_phys(dev, addr);
+
+ if (unlikely(is_swiotlb_buffer(paddr)))
+ swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_DEVICE);
+
+ if (!dev_is_dma_coherent(dev))
+ arch_sync_dma_for_device(paddr, size, dir);
+}
+
+static inline void dma_direct_sync_single_for_cpu(struct device *dev,
+ dma_addr_t addr, size_t size, enum dma_data_direction dir)
+{
+ phys_addr_t paddr = dma_to_phys(dev, addr);
+
+ if (!dev_is_dma_coherent(dev)) {
+ arch_sync_dma_for_cpu(paddr, size, dir);
+ arch_sync_dma_for_cpu_all();
+ }
+
+ if (unlikely(is_swiotlb_buffer(paddr)))
+ swiotlb_tbl_sync_single(dev, paddr, size, dir, SYNC_FOR_CPU);
+
+ if (dir == DMA_FROM_DEVICE)
+ 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)
+{
+ phys_addr_t phys = page_to_phys(page) + offset;
+ dma_addr_t dma_addr = phys_to_dma(dev, phys);
+
+ if (unlikely(swiotlb_force == SWIOTLB_FORCE))
+ return swiotlb_map(dev, phys, size, dir, attrs);
+
+ if (unlikely(!dma_capable(dev, dma_addr, size, true))) {
+ if (swiotlb_force != SWIOTLB_NO_FORCE)
+ 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 (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ arch_sync_dma_for_device(phys, size, dir);
+ return dma_addr;
+}
+
+static inline void dma_direct_unmap_page(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);
+
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ dma_direct_sync_single_for_cpu(dev, addr, size, dir);
+
+ if (unlikely(is_swiotlb_buffer(phys)))
+ swiotlb_tbl_unmap_single(dev, phys, size, size, dir, attrs);
+}
+#endif /* _KERNEL_DMA_DIRECT_H */
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 335ba183e0956a..51bb8fa8eb8948 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -7,7 +7,6 @@
*/
#include <linux/memblock.h> /* for max_pfn */
#include <linux/acpi.h>
-#include <linux/dma-direct.h>
#include <linux/dma-map-ops.h>
#include <linux/export.h>
#include <linux/gfp.h>
@@ -15,6 +14,7 @@
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "debug.h"
+#include "direct.h"

/*
* Managed DMA API
--
2.28.0