diff options
Diffstat (limited to 'arch/sparc64/kernel/iommu_common.h')
| -rw-r--r-- | arch/sparc64/kernel/iommu_common.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/sparc64/kernel/iommu_common.h b/arch/sparc64/kernel/iommu_common.h index a90d046e8024..4b5cafa2877a 100644 --- a/arch/sparc64/kernel/iommu_common.h +++ b/arch/sparc64/kernel/iommu_common.h @@ -30,6 +30,32 @@ */ #define IOMMU_PAGE_SHIFT 13 +#define SG_ENT_PHYS_ADDRESS(SG) (__pa(sg_virt((SG)))) + +static inline unsigned long iommu_num_pages(unsigned long vaddr, + unsigned long slen) +{ + unsigned long npages; + + npages = IO_PAGE_ALIGN(vaddr + slen) - (vaddr & IO_PAGE_MASK); + npages >>= IO_PAGE_SHIFT; + + return npages; +} + +static inline unsigned long calc_npages(struct scatterlist *sglist, int nelems) +{ + unsigned long i, npages = 0; + struct scatterlist *sg; + + for_each_sg(sglist, sg, nelems, i) { + unsigned long paddr = SG_ENT_PHYS_ADDRESS(sg); + npages += iommu_num_pages(paddr, sg->length); + } + + return npages; +} + /* You are _strongly_ advised to enable the following debugging code * any time you make changes to the sg code below, run it for a while * with filesystems mounted read-only before buying the farm... -DaveM |