diff options
Diffstat (limited to 'include/linux/swiotlb.h')
| -rw-r--r-- | include/linux/swiotlb.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index b18ec5533e8c..325af1de0351 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -7,9 +7,31 @@ struct device; struct dma_attrs; struct scatterlist; +/* + * Maximum allowable number of contiguous slabs to map, + * must be a power of 2. What is the appropriate value ? + * The complexity of {map,unmap}_single is linearly dependent on this value. + */ +#define IO_TLB_SEGSIZE 128 + + +/* + * log of the size of each IO TLB slab. The number of slabs is command line + * controllable. + */ +#define IO_TLB_SHIFT 11 + extern void swiotlb_init(void); +extern void *swiotlb_alloc_boot(size_t bytes, unsigned long nslabs); +extern void *swiotlb_alloc(unsigned order, unsigned long nslabs); + +extern dma_addr_t swiotlb_phys_to_bus(phys_addr_t address); +extern phys_addr_t swiotlb_bus_to_phys(dma_addr_t address); + +extern int swiotlb_arch_range_needs_mapping(void *ptr, size_t size); + extern void *swiotlb_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, gfp_t flags); |