To allocate IOVA area at specified address
Signed-off-by: Hiroshi Doyu <hd...@nvidia.com>
---
arch/arm/include/asm/dma-mapping.h | 9 +++++++++
arch/arm/mm/dma-mapping.c | 35 +++++++++++++++++++++++++++++++++++
include/linux/dma-mapping.h | 2 ++
3 files changed, 46 insertions(+), 0 deletions(-)
diff --git a/arch/arm/include/asm/dma-mapping.h
b/arch/arm/include/asm/dma-mapping.h
index 5b86600..f04a533 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -187,6 +187,15 @@ static inline void dma_iova_free(struct device *dev,
dma_addr_t addr,
ops->iova_free(dev, addr, size);
}
+static inline dma_addr_t dma_iova_alloc_at(struct device *dev, dma_addr_t addr,
+ size_t size)
+{
+ struct dma_map_ops *ops = get_dma_ops(dev);
+ BUG_ON(!ops);
+
+ return ops->iova_alloc_at(dev, addr, size);
+}
+
static inline size_t dma_iova_get_free_total(struct device *dev)
{
struct dma_map_ops *ops = get_dma_ops(dev);
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index c18522a..8ca2d1a 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1080,6 +1080,40 @@ static inline dma_addr_t __alloc_iova(struct
dma_iommu_mapping *mapping,
return mapping->base + (start << (mapping->order + PAGE_SHIFT));
}
+static dma_addr_t __alloc_iova_at(struct dma_iommu_mapping *mapping,
+ dma_addr_t iova, size_t size)
+{
+ unsigned int count, start, orig;
+ unsigned long flags;
+
+ count = ((PAGE_ALIGN(size) >> PAGE_SHIFT) +
+ (1 << mapping->order) - 1) >> mapping->order;
+
+ spin_lock_irqsave(&mapping->lock, flags);
+
+ orig = (iova - mapping->base) >> (mapping->order + PAGE_SHIFT);
+ start = bitmap_find_next_zero_area(mapping->bitmap, mapping->bits,
+ orig, count, 0);
+
+ if ((start > mapping->bits) || (orig != start)) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return DMA_ERROR_CODE;
+ }
+
+ bitmap_set(mapping->bitmap, start, count);
+ spin_unlock_irqrestore(&mapping->lock, flags);
+
+ return mapping->base + (start << (mapping->order + PAGE_SHIFT));
+}
+
+static dma_addr_t arm_iommu_iova_alloc_at(struct device *dev, dma_addr_t iova,
+ size_t size)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+
+ return __alloc_iova_at(mapping, iova, size);
+}
+
static dma_addr_t arm_iommu_iova_alloc(struct device *dev, size_t size)
{
struct dma_iommu_mapping *mapping = dev->archdata.mapping;
@@ -1789,6 +1823,7 @@ struct dma_map_ops iommu_ops = {
.sync_sg_for_device = arm_iommu_sync_sg_for_device,
.iova_alloc = arm_iommu_iova_alloc,
+ .iova_alloc_at = arm_iommu_iova_alloc_at,
.iova_free = arm_iommu_iova_free,
.iova_get_free_total = arm_iommu_iova_get_free_total,
.iova_get_free_max = arm_iommu_iova_get_free_max,
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index e85aa04..4cf4427 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -54,6 +54,8 @@ struct dma_map_ops {
u64 (*get_required_mask)(struct device *dev);
#endif
dma_addr_t (*iova_alloc)(struct device *dev, size_t size);
+ dma_addr_t (*iova_alloc_at)(struct device *dev, dma_addr_t dma_addr,
+ size_t size);
void (*iova_free)(struct device *dev, dma_addr_t addr, size_t size);
size_t (*iova_get_free_total)(struct device *dev);
size_t (*iova_get_free_max)(struct device *dev);
--
1.7.5.4
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