diff options
Diffstat (limited to 'include/linux/dma-mapping.h')
| -rw-r--r-- | include/linux/dma-mapping.h | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 52635e91143b..faab0a8210b9 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -632,6 +632,25 @@ static inline unsigned long dma_get_seg_boundary(struct device *dev) return DMA_BIT_MASK(32); } +/** + * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units + * @dev: device to guery the boundary for + * @page_shift: ilog() of the IOMMU page size + * + * Return the segment boundary in IOMMU page units (which may be different from + * the CPU page size) for the passed in device. + * + * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for + * non-DMA API callers. + */ +static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev, + unsigned int page_shift) +{ + if (!dev) + return (U32_MAX >> page_shift) + 1; + return (dma_get_seg_boundary(dev) >> page_shift) + 1; +} + static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask) { if (dev->dma_parms) { |