diff --git a/drivers/infiniband/hw/hfi1/file_ops.c b/drivers/infiniband/hw/hfi1/file_ops.c
index 72c21d7455fd..1a36f995c4f6 100644
--- a/drivers/infiniband/hw/hfi1/file_ops.c
+++ b/drivers/infiniband/hw/hfi1/file_ops.c
@@ -326,6 +326,7 @@ static int hfi1_file_mmap(struct file *fp, struct vm_area_struct *vma)
 	void *memvirt = NULL;
 	dma_addr_t memdma = 0;
 	u8 subctxt, mapio = 0, vmf = 0, type;
+	size_t memdmalen = 0;
 	ssize_t memlen = 0;
 	int ret = 0;
 	u16 ctxt;
@@ -371,7 +372,9 @@ static int hfi1_file_mmap(struct file *fp, struct vm_area_struct *vma)
 		mapio = 1;
 		break;
 	case PIO_CRED: {
+		struct credit_return_base *cr = &dd->cr_base[uctxt->sc->node];
 		u64 cr_page_offset;
+
 		if (flags & VM_WRITE) {
 			ret = -EPERM;
 			goto done;
@@ -381,11 +384,18 @@ static int hfi1_file_mmap(struct file *fp, struct vm_area_struct *vma)
 		 * second or third page allocated for credit returns (if number
 		 * of enabled contexts > 64 and 128 respectively).
 		 */
-		cr_page_offset = ((u64)uctxt->sc->hw_free -
-				  (u64)dd->cr_base[uctxt->sc->node].va) &
+		cr_page_offset = ((u64)uctxt->sc->hw_free - (u64)cr->va) &
 				 PAGE_MASK;
-		memvirt = dd->cr_base[uctxt->sc->node].va + cr_page_offset;
-		memdma = dd->cr_base[uctxt->sc->node].dma + cr_page_offset;
+		/*
+		 * dma_mmap_coherent() describes the whole coherent buffer and
+		 * selects the page within it with vma->vm_pgoff, so pass the
+		 * base of the allocation and its length and let vm_pgoff pick
+		 * the page.
+		 */
+		vma->vm_pgoff = cr_page_offset >> PAGE_SHIFT;
+		memvirt = cr->va;
+		memdma = cr->dma;
+		memdmalen = TXE_NUM_CONTEXTS * sizeof(struct credit_return);
 		memlen = PAGE_SIZE;
 		flags &= ~VM_MAYWRITE;
 		flags |= VM_DONTCOPY | VM_DONTEXPAND;
@@ -567,7 +577,8 @@ static int hfi1_file_mmap(struct file *fp, struct vm_area_struct *vma)
 		ret = 0;
 	} else if (memdma) {
 		ret = dma_mmap_coherent(&dd->pcidev->dev, vma,
-					memvirt, memdma, memlen);
+					memvirt, memdma,
+					memdmalen ? memdmalen : memlen);
 	} else if (mapio) {
 		ret = io_remap_pfn_range(vma, vma->vm_start,
 					 PFN_DOWN(memaddr),