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-rw-r--r--kernel/dma/direct.c121
1 files changed, 115 insertions, 6 deletions
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index de87b0282e74..09e85f6aa4ba 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -1,13 +1,15 @@
// SPDX-License-Identifier: GPL-2.0
/*
- * DMA operations that map physical memory directly without using an IOMMU or
- * flushing caches.
+ * Copyright (C) 2018 Christoph Hellwig.
+ *
+ * DMA operations that map physical memory directly without using an IOMMU.
*/
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/dma-direct.h>
#include <linux/scatterlist.h>
#include <linux/dma-contiguous.h>
+#include <linux/dma-noncoherent.h>
#include <linux/pfn.h>
#include <linux/set_memory.h>
@@ -58,8 +60,8 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
return addr + size - 1 <= dev->coherent_dma_mask;
}
-void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
- gfp_t gfp, unsigned long attrs)
+void *dma_direct_alloc_pages(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
int page_order = get_order(size);
@@ -124,7 +126,7 @@ again:
* NOTE: this function must never look at the dma_addr argument, because we want
* to be able to use it as a helper for iommu implementations as well.
*/
-void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs)
{
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
@@ -136,14 +138,106 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
free_pages((unsigned long)cpu_addr, page_order);
}
+void *dma_direct_alloc(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+{
+ if (!dev_is_dma_coherent(dev))
+ return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
+ return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
+}
+
+void dma_direct_free(struct device *dev, size_t size,
+ void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
+{
+ if (!dev_is_dma_coherent(dev))
+ arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
+ else
+ dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
+}
+
+static 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)
+{
+ if (!dev_is_dma_coherent(dev) &&
+ IS_ENABLED(CONFIG_DMA_NONCOHERENT_MMAP))
+ return arch_dma_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
+ return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
+}
+
+static void dma_direct_sync_single_for_device(struct device *dev,
+ dma_addr_t addr, size_t size, enum dma_data_direction dir)
+{
+ if (dev_is_dma_coherent(dev))
+ return;
+ arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir);
+}
+
+static void dma_direct_sync_sg_for_device(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *sg;
+ int i;
+
+ if (dev_is_dma_coherent(dev))
+ return;
+
+ for_each_sg(sgl, sg, nents, i)
+ arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir);
+}
+
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
+static void dma_direct_sync_single_for_cpu(struct device *dev,
+ dma_addr_t addr, size_t size, enum dma_data_direction dir)
+{
+ if (dev_is_dma_coherent(dev))
+ return;
+ arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir);
+ arch_sync_dma_for_cpu_all(dev);
+}
+
+static void dma_direct_sync_sg_for_cpu(struct device *dev,
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *sg;
+ int i;
+
+ if (dev_is_dma_coherent(dev))
+ return;
+
+ for_each_sg(sgl, sg, nents, i)
+ arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir);
+ arch_sync_dma_for_cpu_all(dev);
+}
+
+static void dma_direct_unmap_page(struct device *dev, dma_addr_t addr,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ dma_direct_sync_single_for_cpu(dev, addr, size, dir);
+}
+
+static void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
+ int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ dma_direct_sync_sg_for_cpu(dev, sgl, nents, dir);
+}
+#endif
+
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)
{
- dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset;
+ phys_addr_t phys = page_to_phys(page) + offset;
+ dma_addr_t dma_addr = phys_to_dma(dev, phys);
if (!check_addr(dev, dma_addr, size, __func__))
return DIRECT_MAPPING_ERROR;
+
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ dma_direct_sync_single_for_device(dev, dma_addr, size, dir);
return dma_addr;
}
@@ -162,6 +256,8 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
sg_dma_len(sg) = sg->length;
}
+ if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+ dma_direct_sync_sg_for_device(dev, sgl, nents, dir);
return nents;
}
@@ -197,9 +293,22 @@ int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
const struct dma_map_ops dma_direct_ops = {
.alloc = dma_direct_alloc,
.free = dma_direct_free,
+ .mmap = dma_direct_mmap,
.map_page = dma_direct_map_page,
.map_sg = dma_direct_map_sg,
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE)
+ .sync_single_for_device = dma_direct_sync_single_for_device,
+ .sync_sg_for_device = dma_direct_sync_sg_for_device,
+#endif
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL)
+ .sync_single_for_cpu = dma_direct_sync_single_for_cpu,
+ .sync_sg_for_cpu = dma_direct_sync_sg_for_cpu,
+ .unmap_page = dma_direct_unmap_page,
+ .unmap_sg = dma_direct_unmap_sg,
+#endif
.dma_supported = dma_direct_supported,
.mapping_error = dma_direct_mapping_error,
+ .cache_sync = arch_dma_cache_sync,
};
EXPORT_SYMBOL(dma_direct_ops);