diff options
| -rw-r--r-- | include/linux/iommu-helper.h | 3 | ||||
| -rw-r--r-- | lib/iommu-helper.c | 9 |
2 files changed, 12 insertions, 0 deletions
diff --git a/include/linux/iommu-helper.h b/include/linux/iommu-helper.h index a6d0586e2bf..3b068e5b567 100644 --- a/include/linux/iommu-helper.h +++ b/include/linux/iommu-helper.h @@ -23,4 +23,7 @@ extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size, extern void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr); +extern unsigned long iommu_num_pages(unsigned long addr, unsigned long len, + unsigned long io_page_size); + #endif diff --git a/lib/iommu-helper.c b/lib/iommu-helper.c index 5d90074dca7..75dbda03f4f 100644 --- a/lib/iommu-helper.c +++ b/lib/iommu-helper.c @@ -79,3 +79,12 @@ void iommu_area_free(unsigned long *map, unsigned long start, unsigned int nr) } } EXPORT_SYMBOL(iommu_area_free); + +unsigned long iommu_num_pages(unsigned long addr, unsigned long len, + unsigned long io_page_size) +{ + unsigned long size = (addr & (io_page_size - 1)) + len; + + return DIV_ROUND_UP(size, io_page_size); +} +EXPORT_SYMBOL(iommu_num_pages); |