author was assuming that nextpaddr declared *inside* the do loop would

    survive within the loop.  This is not guarenteed by C.  I have moved
    the nextpaddr declaration to outside the do loop.

1 files changed, 37 insertions, 30 deletions

diff --git a/sys/amd64/amd64/busdma_machdep.c b/sys/amd64/amd64/busdma_machdep.c
index d35967e..30571e5 100644
--- a/sys/amd64/amd64/busdma_machdep.c
+++ b/sys/amd64/amd64/busdma_machdep.c
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *      $Id: busdma_machdep.c,v 1.10 1998/10/07 03:38:14 gibbs Exp $
+ *      $Id: busdma_machdep.c,v 1.11 1998/10/13 08:24:33 dg Exp $
  */
 
 #include <sys/param.h>
@@ -435,38 +435,45 @@ bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
 	seg = 1;
 	sg->ds_len = 0;
 
-	do {
-		bus_size_t	size;
-		vm_offset_t	nextpaddr;	/* GCC warning expected */
+	{
+		/*
+		 * note: nextpaddr not used on first loop
+		 */
+		vm_offset_t	nextpaddr = 0;
 
-		paddr = pmap_kextract(vaddr);
-		size = PAGE_SIZE - (paddr & PAGE_MASK);
-		if (size > buflen)
-			size = buflen;
+		do {
+			bus_size_t	size;
 
-		if (map->pagesneeded != 0
-		 && run_filter(dmat, paddr)) {
-			paddr = add_bounce_page(dmat, map, vaddr, size);
-		}
+			paddr = pmap_kextract(vaddr);
+			size = PAGE_SIZE - (paddr & PAGE_MASK);
+			if (size > buflen)
+				size = buflen;
+
+			if (map->pagesneeded != 0
+			 && run_filter(dmat, paddr)) {
+				paddr = add_bounce_page(dmat, map, 
+				    vaddr, size);
+			}
 
-		if (sg->ds_len == 0) {
-			sg->ds_addr = paddr;
-			sg->ds_len = size;
-		} else if (paddr == nextpaddr) {
-			sg->ds_len += size;
-		} else {
-			/* Go to the next segment */
-			sg++;
-			seg++;
-			if (seg > dmat->nsegments)
-				break;
-			sg->ds_addr = paddr;
-			sg->ds_len = size;
-		}
-		vaddr += size;
-		nextpaddr = paddr + size;
-		buflen -= size;
-	} while (buflen > 0);
+			if (sg->ds_len == 0) {
+				sg->ds_addr = paddr;
+				sg->ds_len = size;
+			} else if (paddr == nextpaddr) {
+				sg->ds_len += size;
+			} else {
+				/* Go to the next segment */
+				sg++;
+				seg++;
+				if (seg > dmat->nsegments)
+					break;
+				sg->ds_addr = paddr;
+				sg->ds_len = size;
+			}
+			vaddr += size;
+			nextpaddr = paddr + size;
+			buflen -= size;
+		} while (buflen > 0);
+	}
 
 	if (buflen != 0) {
 		printf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",