To allocate IOVA area at specified address
Signed-off-by: Hiroshi Doyu hdoyu@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);