swiotlb: Keep offset in a page strictly smaller than PAGE_SIZE.

Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/arch/i386/kernel/swiotlb.c b/arch/i386/kernel/swiotlb.c
index abfbc212a4f1c5e7807eeb8cb6b4fa72f6fe5298..dc03ca5c21adf198dd25e592cd9d57bd5cf62f44 100644 (file)
--- a/arch/i386/kernel/swiotlb.c
+++ b/arch/i386/kernel/swiotlb.c
@@ -380,7 +380,7 @@ map_single(struct device *hwdev, struct phys_addr buffer, size_t size, int dir)
        for (i = 0; i < nslots; i++) {
                io_tlb_orig_addr[index+i] = slot_buf;
                slot_buf.offset += 1 << IO_TLB_SHIFT;
-               if (slot_buf.offset > PAGE_SIZE) {
+               if (slot_buf.offset >= PAGE_SIZE) {
                        slot_buf.page++;
                        slot_buf.offset -= PAGE_SIZE;
                }