dma_patch.diff

diff --git a/sys/arm/arm/busdma_machdep-v6.c b/sys/arm/arm/busdma_machdep-v6.c
index d62522e..2831418 100644
--- a/sys/arm/arm/busdma_machdep-v6.c
+++ b/sys/arm/arm/busdma_machdep-v6.c
@@ -1080,10 +1080,14 @@ _bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
 			curaddr = add_bounce_page(dmat, map, 0, curaddr,
 			    sgsize);
 		} else {
-			if (map->sync_count > 0)
-				sl_end = VM_PAGE_TO_PHYS(sl->pages) +
-				    sl->dataoffs + sl->datacount;
-
+			if (map->sync_count > 0) {
+				if (sl->vaddr == 0)
+					sl_end = VM_PAGE_TO_PHYS(sl->pages) +
+					    sl->dataoffs + sl->datacount;
+				else
+					sl_end = pmap_kextract(sl->vaddr) +
+					    sl->datacount;
+			}
 			if (map->sync_count == 0 || curaddr != sl_end) {
 				if (++map->sync_count > dmat->nsegments)
 					break;
@@ -1091,6 +1095,11 @@ _bus_dmamap_load_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
 				sl->vaddr = 0;
 				sl->datacount = sgsize;
 				sl->pages = PHYS_TO_VM_PAGE(curaddr);
+				if (sl->pages == NULL) {
+					panic("%s: attempt to start DMA from"
+					    " not present memory: 0x%08lx",
+					     __func__, curaddr);
+				}
 				sl->dataoffs = curaddr & PAGE_MASK;
 			} else
 				sl->datacount += sgsize;
@@ -1193,8 +1202,12 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
 			    sgsize);
 		} else {
 			if (map->sync_count > 0) {
-				sl_pend = VM_PAGE_TO_PHYS(sl->pages) +
-				    sl->dataoffs + sl->datacount;
+				if (sl->vaddr == 0)
+					sl_pend = VM_PAGE_TO_PHYS(sl->pages) +
+					    sl->dataoffs + sl->datacount;
+				else
+					sl_pend = pmap_kextract(sl->vaddr) +
+					    sl->datacount;
 				sl_vend = sl->vaddr + sl->datacount;
 			}
 
@@ -1208,6 +1221,12 @@ _bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
 				sl->vaddr = kvaddr;
 				sl->datacount = sgsize;
 				sl->pages = PHYS_TO_VM_PAGE(curaddr);
+				if ((kvaddr == 0) && (sl->pages == NULL)) {
+					panic("%s: attempt load unmapped"
+					    " DMA memory from not"
+					    " present memory: 0x%08lx",
+					     __func__, curaddr);
+				}
 				sl->dataoffs = curaddr & PAGE_MASK;
 			} else
 				sl->datacount += sgsize;
@@ -1307,7 +1326,10 @@ dma_dcache_sync(struct sync_list *sl, bus_dmasync_op_t op)
 	offset = sl->dataoffs;
 	m = sl->pages;
 	size = sl->datacount;
-	pa = VM_PAGE_TO_PHYS(m) | offset;
+	if (sl->vaddr == 0)
+		pa = VM_PAGE_TO_PHYS(m) | offset;
+	else
+		pa = pmap_kextract(sl->vaddr);
 
 	for ( ; size != 0; size -= len, pa += len, offset = 0, ++m) {
 		tempva = 0;
@@ -1319,10 +1341,11 @@ dma_dcache_sync(struct sync_list *sl, bus_dmasync_op_t op)
 			len = sl->datacount;
 			va = sl->vaddr;
 		}
+#if 0 /* Remove me */
 		KASSERT(pa == (VM_PAGE_TO_PHYS(m) | offset),
 		    ("unexpected vm_page_t phys: 0x%08x != 0x%08x",
 		    VM_PAGE_TO_PHYS(m) | offset, pa));
-
+#endif
 		switch (op) {
 		case BUS_DMASYNC_PREWRITE:
 		case BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD: