1 files changed, 15 insertions, 4 deletions

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index bfe02b8fc55b..d23762e6652c 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -105,9 +105,9 @@ setup_io_tlb_npages(char *str)
         if (!strcmp(str, "force"))
                 swiotlb_force = 1;
 
-        return 1;
+        return 0;
 }
-__setup("swiotlb=", setup_io_tlb_npages);
+early_param("swiotlb", setup_io_tlb_npages);
 /* make io_tlb_overflow tunable too? */
 
 unsigned long swiotlb_nr_tbl(void)
@@ -115,6 +115,18 @@ unsigned long swiotlb_nr_tbl(void)
         return io_tlb_nslabs;
 }
 EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);
+
+/* default to 64MB */
+#define IO_TLB_DEFAULT_SIZE (64UL<<20)
+unsigned long swiotlb_size_or_default(void)
+{
+        unsigned long size;
+
+        size = io_tlb_nslabs << IO_TLB_SHIFT;
+
+        return size ? size : (IO_TLB_DEFAULT_SIZE);
+}
+
 /* Note that this doesn't work with highmem page */
 static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
                                       volatile void *address)
@@ -188,8 +200,7 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
 void  __init
 swiotlb_init(int verbose)
 {
-        /* default to 64MB */
-        size_t default_size = 64UL<<20;
+        size_t default_size = IO_TLB_DEFAULT_SIZE;
         unsigned char *vstart;
         unsigned long bytes;