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-rw-r--r--kernel/dma/Kconfig12
-rw-r--r--kernel/dma/Makefile3
-rw-r--r--kernel/dma/contiguous.c31
-rw-r--r--kernel/dma/debug.c8
-rw-r--r--kernel/dma/direct.c74
-rw-r--r--kernel/dma/mapping.c214
6 files changed, 238 insertions, 104 deletions
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 1da3f44f2565..f4770fcfa62b 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -5,6 +5,17 @@ config HAS_DMA
depends on !NO_DMA
default y
+config DMA_OPS
+ bool
+
+#
+# IOMMU drivers that can bypass the IOMMU code and optionally use the direct
+# mapping fast path should select this option and set the dma_ops_bypass
+# flag in struct device where applicable
+#
+config DMA_OPS_BYPASS
+ bool
+
config NEED_SG_DMA_LENGTH
bool
@@ -60,6 +71,7 @@ config DMA_NONCOHERENT_CACHE_SYNC
config DMA_VIRT_OPS
bool
depends on HAS_DMA
+ select DMA_OPS
config SWIOTLB
bool
diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile
index 370f63344e9c..32c7c1942bbd 100644
--- a/kernel/dma/Makefile
+++ b/kernel/dma/Makefile
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_HAS_DMA) += mapping.o direct.o dummy.o
+obj-$(CONFIG_HAS_DMA) += mapping.o direct.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
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 15bc5026c485..cff7e60968b9 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -215,6 +215,13 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
return cma_release(dev_get_cma_area(dev), pages, count);
}
+static struct page *cma_alloc_aligned(struct cma *cma, size_t size, gfp_t gfp)
+{
+ unsigned int align = min(get_order(size), CONFIG_CMA_ALIGNMENT);
+
+ return cma_alloc(cma, size >> PAGE_SHIFT, align, gfp & __GFP_NOWARN);
+}
+
/**
* dma_alloc_contiguous() - allocate contiguous pages
* @dev: Pointer to device for which the allocation is performed.
@@ -231,24 +238,14 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
*/
struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)
{
- size_t count = size >> PAGE_SHIFT;
- struct page *page = NULL;
- struct cma *cma = NULL;
-
- if (dev && dev->cma_area)
- cma = dev->cma_area;
- else if (count > 1)
- cma = dma_contiguous_default_area;
-
/* CMA can be used only in the context which permits sleeping */
- if (cma && gfpflags_allow_blocking(gfp)) {
- size_t align = get_order(size);
- size_t cma_align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT);
-
- page = cma_alloc(cma, count, cma_align, gfp & __GFP_NOWARN);
- }
-
- return page;
+ if (!gfpflags_allow_blocking(gfp))
+ return NULL;
+ if (dev->cma_area)
+ return cma_alloc_aligned(dev->cma_area, size, gfp);
+ if (size <= PAGE_SIZE || !dma_contiguous_default_area)
+ return NULL;
+ return cma_alloc_aligned(dma_contiguous_default_area, size, gfp);
}
/**
diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c
index d628ab09d97b..5aba04075530 100644
--- a/kernel/dma/debug.c
+++ b/kernel/dma/debug.c
@@ -144,8 +144,12 @@ static const char *type2name[] = {
[dma_debug_resource] = "resource",
};
-static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE",
- "DMA_FROM_DEVICE", "DMA_NONE" };
+static const char *dir2name[] = {
+ [DMA_BIDIRECTIONAL] = "DMA_BIDIRECTIONAL",
+ [DMA_TO_DEVICE] = "DMA_TO_DEVICE",
+ [DMA_FROM_DEVICE] = "DMA_FROM_DEVICE",
+ [DMA_NONE] = "DMA_NONE",
+};
/*
* The access to some variables in this macro is racy. We can't use atomic_t
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 67f060b86a73..bb0041e99659 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -10,11 +10,9 @@
#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/vmalloc.h>
#include <linux/set_memory.h>
-#include <linux/swiotlb.h>
/*
* Most architectures use ZONE_DMA for the first 16 Megabytes, but some use it
@@ -304,19 +302,6 @@ void dma_direct_free(struct device *dev, size_t size,
#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
defined(CONFIG_SWIOTLB)
-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);
-}
-EXPORT_SYMBOL(dma_direct_sync_single_for_device);
-
void dma_direct_sync_sg_for_device(struct device *dev,
struct scatterlist *sgl, int nents, enum dma_data_direction dir)
{
@@ -335,27 +320,11 @@ void dma_direct_sync_sg_for_device(struct device *dev,
dir);
}
}
-EXPORT_SYMBOL(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) || \
defined(CONFIG_SWIOTLB)
-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);
-}
-EXPORT_SYMBOL(dma_direct_sync_single_for_cpu);
-
void dma_direct_sync_sg_for_cpu(struct device *dev,
struct scatterlist *sgl, int nents, enum dma_data_direction dir)
{
@@ -376,20 +345,6 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
if (!dev_is_dma_coherent(dev))
arch_sync_dma_for_cpu_all();
}
-EXPORT_SYMBOL(dma_direct_sync_sg_for_cpu);
-
-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);
-}
-EXPORT_SYMBOL(dma_direct_unmap_page);
void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
int nents, enum dma_data_direction dir, unsigned long attrs)
@@ -401,35 +356,8 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
dma_direct_unmap_page(dev, sg->dma_address, sg_dma_len(sg), dir,
attrs);
}
-EXPORT_SYMBOL(dma_direct_unmap_sg);
#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)
-{
- 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;
-}
-EXPORT_SYMBOL(dma_direct_map_page);
-
int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs)
{
@@ -450,7 +378,6 @@ out_unmap:
dma_direct_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC);
return 0;
}
-EXPORT_SYMBOL(dma_direct_map_sg);
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)
@@ -467,7 +394,6 @@ dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
return dma_addr;
}
-EXPORT_SYMBOL(dma_direct_map_resource);
int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
void *cpu_addr, dma_addr_t dma_addr, size_t size,
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index a8c18c9a796f..0d129421e75f 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -105,6 +105,196 @@ void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
}
EXPORT_SYMBOL(dmam_alloc_attrs);
+static bool dma_go_direct(struct device *dev, dma_addr_t mask,
+ const struct dma_map_ops *ops)
+{
+ if (likely(!ops))
+ return true;
+#ifdef CONFIG_DMA_OPS_BYPASS
+ if (dev->dma_ops_bypass)
+ return min_not_zero(mask, dev->bus_dma_limit) >=
+ dma_direct_get_required_mask(dev);
+#endif
+ return false;
+}
+
+
+/*
+ * Check if the devices uses a direct mapping for streaming DMA operations.
+ * This allows IOMMU drivers to set a bypass mode if the DMA mask is large
+ * enough.
+ */
+static inline bool dma_alloc_direct(struct device *dev,
+ const struct dma_map_ops *ops)
+{
+ return dma_go_direct(dev, dev->coherent_dma_mask, ops);
+}
+
+static inline bool dma_map_direct(struct device *dev,
+ const struct dma_map_ops *ops)
+{
+ return dma_go_direct(dev, *dev->dma_mask, ops);
+}
+
+dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
+ size_t offset, size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ dma_addr_t addr;
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
+ else
+ addr = ops->map_page(dev, page, offset, size, dir, attrs);
+ debug_dma_map_page(dev, page, offset, size, dir, addr);
+
+ return addr;
+}
+EXPORT_SYMBOL(dma_map_page_attrs);
+
+void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ dma_direct_unmap_page(dev, addr, size, dir, attrs);
+ else if (ops->unmap_page)
+ ops->unmap_page(dev, addr, size, dir, attrs);
+ debug_dma_unmap_page(dev, addr, size, dir);
+}
+EXPORT_SYMBOL(dma_unmap_page_attrs);
+
+/*
+ * dma_maps_sg_attrs returns 0 on error and > 0 on success.
+ * It should never return a value < 0.
+ */
+int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ int ents;
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ ents = dma_direct_map_sg(dev, sg, nents, dir, attrs);
+ else
+ ents = ops->map_sg(dev, sg, nents, dir, attrs);
+ BUG_ON(ents < 0);
+ debug_dma_map_sg(dev, sg, nents, ents, dir);
+
+ return ents;
+}
+EXPORT_SYMBOL(dma_map_sg_attrs);
+
+void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ debug_dma_unmap_sg(dev, sg, nents, dir);
+ if (dma_map_direct(dev, ops))
+ dma_direct_unmap_sg(dev, sg, nents, dir, attrs);
+ else if (ops->unmap_sg)
+ ops->unmap_sg(dev, sg, nents, dir, attrs);
+}
+EXPORT_SYMBOL(dma_unmap_sg_attrs);
+
+dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ dma_addr_t addr = DMA_MAPPING_ERROR;
+
+ BUG_ON(!valid_dma_direction(dir));
+
+ /* Don't allow RAM to be mapped */
+ if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr))))
+ return DMA_MAPPING_ERROR;
+
+ if (dma_map_direct(dev, ops))
+ addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs);
+ else if (ops->map_resource)
+ addr = ops->map_resource(dev, phys_addr, size, dir, attrs);
+
+ debug_dma_map_resource(dev, phys_addr, size, dir, addr);
+ return addr;
+}
+EXPORT_SYMBOL(dma_map_resource);
+
+void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir, unsigned long attrs)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (!dma_map_direct(dev, ops) && ops->unmap_resource)
+ ops->unmap_resource(dev, addr, size, dir, attrs);
+ debug_dma_unmap_resource(dev, addr, size, dir);
+}
+EXPORT_SYMBOL(dma_unmap_resource);
+
+void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
+ enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ dma_direct_sync_single_for_cpu(dev, addr, size, dir);
+ else if (ops->sync_single_for_cpu)
+ ops->sync_single_for_cpu(dev, addr, size, dir);
+ debug_dma_sync_single_for_cpu(dev, addr, size, dir);
+}
+EXPORT_SYMBOL(dma_sync_single_for_cpu);
+
+void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
+ size_t size, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ dma_direct_sync_single_for_device(dev, addr, size, dir);
+ else if (ops->sync_single_for_device)
+ ops->sync_single_for_device(dev, addr, size, dir);
+ debug_dma_sync_single_for_device(dev, addr, size, dir);
+}
+EXPORT_SYMBOL(dma_sync_single_for_device);
+
+void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ dma_direct_sync_sg_for_cpu(dev, sg, nelems, dir);
+ else if (ops->sync_sg_for_cpu)
+ ops->sync_sg_for_cpu(dev, sg, nelems, dir);
+ debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir);
+}
+EXPORT_SYMBOL(dma_sync_sg_for_cpu);
+
+void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nelems, enum dma_data_direction dir)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ BUG_ON(!valid_dma_direction(dir));
+ if (dma_map_direct(dev, ops))
+ dma_direct_sync_sg_for_device(dev, sg, nelems, dir);
+ else if (ops->sync_sg_for_device)
+ ops->sync_sg_for_device(dev, sg, nelems, dir);
+ debug_dma_sync_sg_for_device(dev, sg, nelems, dir);
+}
+EXPORT_SYMBOL(dma_sync_sg_for_device);
+
/*
* Create scatter-list for the already allocated DMA buffer.
*/
@@ -138,7 +328,7 @@ int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
return dma_direct_get_sgtable(dev, sgt, cpu_addr, dma_addr,
size, attrs);
if (!ops->get_sgtable)
@@ -208,7 +398,7 @@ bool dma_can_mmap(struct device *dev)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
return dma_direct_can_mmap(dev);
return ops->mmap != NULL;
}
@@ -233,7 +423,7 @@ int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
return dma_direct_mmap(dev, vma, cpu_addr, dma_addr, size,
attrs);
if (!ops->mmap)
@@ -246,7 +436,7 @@ u64 dma_get_required_mask(struct device *dev)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
return dma_direct_get_required_mask(dev);
if (ops->get_required_mask)
return ops->get_required_mask(dev);
@@ -277,7 +467,7 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
/* let the implementation decide on the zone to allocate from: */
flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs);
else if (ops->alloc)
cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
@@ -309,7 +499,7 @@ void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
return;
debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
dma_direct_free(dev, size, cpu_addr, dma_handle, attrs);
else if (ops->free)
ops->free(dev, size, cpu_addr, dma_handle, attrs);
@@ -320,7 +510,11 @@ int dma_supported(struct device *dev, u64 mask)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ /*
+ * ->dma_supported sets the bypass flag, so we must always call
+ * into the method here unless the device is truly direct mapped.
+ */
+ if (!ops)
return dma_direct_supported(dev, mask);
if (!ops->dma_supported)
return 1;
@@ -376,7 +570,7 @@ void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
BUG_ON(!valid_dma_direction(dir));
- if (dma_is_direct(ops))
+ if (dma_alloc_direct(dev, ops))
arch_dma_cache_sync(dev, vaddr, size, dir);
else if (ops->cache_sync)
ops->cache_sync(dev, vaddr, size, dir);
@@ -388,7 +582,7 @@ size_t dma_max_mapping_size(struct device *dev)
const struct dma_map_ops *ops = get_dma_ops(dev);
size_t size = SIZE_MAX;
- if (dma_is_direct(ops))
+ if (dma_map_direct(dev, ops))
size = dma_direct_max_mapping_size(dev);
else if (ops && ops->max_mapping_size)
size = ops->max_mapping_size(dev);
@@ -401,7 +595,7 @@ bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
- if (dma_is_direct(ops))
+ if (dma_map_direct(dev, ops))
return dma_direct_need_sync(dev, dma_addr);
return ops->sync_single_for_cpu || ops->sync_single_for_device;
}