swiotlb: optimize get_max_slots()

[platform/kernel/linux-rpi.git] / kernel / dma / swiotlb.c

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 50a0e9c..394494a 100644 (file)
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -903,9 +903,7 @@ static inline phys_addr_t slot_addr(phys_addr_t start, phys_addr_t idx)
  */
 static inline unsigned long get_max_slots(unsigned long boundary_mask)
 {
-       if (boundary_mask == ~0UL)
-               return 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
-       return nr_slots(boundary_mask + 1);
+       return (boundary_mask >> IO_TLB_SHIFT) + 1;
 }
 
 static unsigned int wrap_area_index(struct io_tlb_pool *mem, unsigned int index)