diff options
Diffstat (limited to 'drivers/iommu/dma-iommu.c')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 3672d619bcb6..2a9fa0c8cc00 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1038,6 +1038,21 @@ out_unmap: return NULL; } +/* + * This is the actual return value from the iommu_dma_alloc_noncontiguous. + * + * The users of the DMA API should only care about the sg_table, but to make + * the DMA-API internal vmaping and freeing easier we stash away the page + * array as well (except for the fallback case). This can go away any time, + * e.g. when a vmap-variant that takes a scatterlist comes along. + */ +struct dma_sgt_handle { + struct sg_table sgt; + struct page **pages; +}; +#define sgt_handle(sgt) \ + container_of((sgt), struct dma_sgt_handle, sgt) + struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, size_t size, enum dma_data_direction dir, gfp_t gfp, unsigned long attrs) { @@ -1066,6 +1081,24 @@ void iommu_dma_free_noncontiguous(struct device *dev, size_t size, kfree(sh); } +void *iommu_dma_vmap_noncontiguous(struct device *dev, size_t size, + struct sg_table *sgt) +{ + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + + return vmap(sgt_handle(sgt)->pages, count, VM_MAP, PAGE_KERNEL); +} + +int iommu_dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma, + size_t size, struct sg_table *sgt) +{ + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + + if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff) + return -ENXIO; + return vm_map_pages(vma, sgt_handle(sgt)->pages, count); +} + void iommu_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) { |