diff --git a/src/common_map.c b/src/common_map.c
index 8757151..68044cd 100644
--- a/src/common_map.c
+++ b/src/common_map.c
@@ -51,5 +51,11 @@ _pci_hidden int
 pci_device_generic_unmap_range(struct pci_device *dev,
 			       struct pci_device_mapping *map)
 {
+#ifdef __alpha__
+    if (map->pre_bwx && map->memory_sparse) {
+	munmap(map->memory_sparse, map->size**(1<<5));
+    }
+#endif
+
     return (munmap(map->memory, map->size) == -1) ? errno : 0;
 }
diff --git a/src/linux_sysfs.c b/src/linux_sysfs.c
index 1832ee7..e24de74 100644
--- a/src/linux_sysfs.c
+++ b/src/linux_sysfs.c
@@ -548,10 +548,28 @@ pci_device_linux_sysfs_map_range(struct pci_device *dev,
              map->region);
 
     fd = open(name, open_flags);
+
+#ifdef __alpha__
+    map->pre_bwx = 0;
     if (fd == -1) {
-        return errno;
+	/* Attempt to map resourceX_dense which exists on non-BWX Alphas. */
+	snprintf(name, 255, "%s/%04x:%02x:%02x.%1u/resource%u_dense",
+		 SYS_BUS_PCI,
+		 dev->domain,
+		 dev->bus,
+		 dev->dev,
+		 dev->func,
+		 map->region);
+	fd = open(name, open_flags);
+	if (fd != -1) {
+	    map->pre_bwx = 1;
+	}
     }
+#endif
 
+    if (fd == -1) {
+	return errno;
+    }
 
     map->memory = mmap(NULL, map->size, prot, MAP_SHARED, fd, offset);
     if (map->memory == MAP_FAILED) {
@@ -597,6 +615,45 @@ pci_device_linux_sysfs_map_range(struct pci_device *dev,
     }
 #endif
 
+#ifdef __alpha__
+    if (map->pre_bwx && dev->regions[map->region].is_IO) {
+	/* Also map sparse mapping for IO.
+	 * This map is only needed for byte or word read/writes, but we
+	 * don't know what the calling routine intends to do so we always
+	 * map sparse.
+	 */
+	close(fd);
+
+	snprintf(name, 255, "%s/%04x:%02x:%02x.%1u/resource%u_sparse",
+		 SYS_BUS_PCI,
+		 dev->domain,
+		 dev->bus,
+		 dev->dev,
+		 dev->func,
+		 map->region);
+	fd = open(name, open_flags);
+	if (fd == -1) {
+	    /* We fail -- any attempt at a byte or word access to the dense
+	     * mapping by the caller will result in a bus error.
+	     */
+	    int saved_errno = errno;
+	    map->memory_sparse = NULL;
+	    pci_device_generic_unmap_range(dev, map);
+	    return saved_errno;
+	}
+
+	map->memory_sparse = mmap(NULL, map->size*(1<<5), prot,
+					MAP_SHARED, fd, offset*(1<<5));
+	if (map->memory_sparse == MAP_FAILED) {
+	    int saved_errno = errno;
+	    map->memory_sparse = NULL;
+	    pci_device_generic_unmap_range(dev, map);
+	    close(fd);
+	    return saved_errno;
+	}
+    }
+#endif
+
     close(fd);
 
     return 0;
diff --git a/src/pciaccess_private.h b/src/pciaccess_private.h
index 77eb57b..e0828f6 100644
--- a/src/pciaccess_private.h
+++ b/src/pciaccess_private.h
@@ -85,6 +85,10 @@ struct pci_device_mapping {
     unsigned region;
     unsigned flags;
     void *memory;
+#ifdef __alpha__
+    void *memory_sparse;
+    int pre_bwx;
+#endif
 };
 
 struct pci_io_handle {