+ /*
+ * Found a hole right after below our entry but
+ * make sure we don't erroneously extend backwards.
+ *
+ * Hit.
+ */
+
+ hole_entry = hole_entry->vme_prev;
+ }
+
+ } else if (hole_entry->vme_start > old_entry->vme_end) {
+
+ /*
+ * Useless hint. Start from the top.
+ */
+
+ hole_entry = (vm_map_entry_t) map->holes_list;
+ }
+
+ if (hole_entry != (vm_map_entry_t) map->holes_list) {
+ if (hole_entry->vme_start > old_entry->vme_start) {
+ panic("Hole hint failed: Hole entry start: 0x%llx, entry start: 0x%llx, map hole start: 0x%llx, map hint start: 0x%llx\n",
+ (unsigned long long)hole_entry->vme_start,
+ (unsigned long long)old_entry->vme_start,
+ (unsigned long long)map->holes_list->start,
+ (unsigned long long)map->hole_hint->start);
+ }
+ if (hole_entry->vme_end > old_entry->vme_start) {
+ panic("Hole hint failed: Hole entry end: 0x%llx, entry start: 0x%llx, map hole start: 0x%llx, map hint start: 0x%llx\n",
+ (unsigned long long)hole_entry->vme_end,
+ (unsigned long long)old_entry->vme_start,
+ (unsigned long long)map->holes_list->start,
+ (unsigned long long)map->hole_hint->start);
+ }
+ }
+
+ while (1) {
+
+ next_hole_entry = hole_entry->vme_next;
+
+ /*
+ * Hole is right above the entry.
+ */
+ if (hole_entry->vme_end == old_entry->vme_start) {
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ /*
+ * Is there another hole right below the entry?
+ * Can we combine holes?
+ */
+
+ if (old_entry->vme_end == hole_entry->vme_next->vme_start) {
+
+ vm_map_combine_hole(map, hole_entry);
+ } else {
+
+ hole_entry->vme_end = old_entry->vme_end;
+ }
+ create_new_hole = FALSE;
+#if DEBUG
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+ break;
+ }
+
+ /*
+ * Hole is right below the entry.
+ */
+ if (hole_entry->vme_start == old_entry->vme_end) {
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ hole_entry->vme_start = old_entry->vme_start;
+ create_new_hole = FALSE;
+
+#if DEBUG
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+ break;
+ }
+
+ /*
+ * Hole is beyond our entry. Let's go back to the last hole
+ * before our entry so we have the right place to link up the
+ * new hole that will be needed.
+ */
+ if (hole_entry->vme_start > old_entry->vme_end) {
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ if (hole_entry != (vm_map_entry_t) map->holes_list) {
+ assert(hole_entry->vme_start != old_entry->vme_start);
+ hole_entry = hole_entry->vme_prev;
+ }
+ break;
+ }
+
+ hole_entry = next_hole_entry;
+
+ if (hole_entry == (vm_map_entry_t)map->holes_list) {
+ hole_entry = hole_entry->vme_prev;
+ break;
+ }
+ }
+ }
+
+ if (create_new_hole) {
+ struct vm_map_links *new_hole_entry = NULL;
+ vm_map_entry_t l_next, l_prev;
+
+ new_hole_entry = zalloc(vm_map_holes_zone);
+
+ /*
+ * First hole in the map?
+ * OR
+ * A hole that is located above the current first hole in the map?
+ */
+ if (map->holes_list == NULL || (hole_entry == (vm_map_entry_t) map->holes_list && hole_entry->vme_start > old_entry->vme_start)) {
+
+ if (map->holes_list == NULL) {
+
+ map->holes_list = new_hole_entry;
+ new_hole_entry->prev = new_hole_entry->next = (vm_map_entry_t)map->holes_list;
+ } else {
+
+ l_next = (vm_map_entry_t) map->holes_list;
+ l_prev = map->holes_list->prev;
+ map->holes_list = new_hole_entry;
+ new_hole_entry->next = l_next;
+ new_hole_entry->prev = l_prev;
+
+ l_prev->vme_next = l_next->vme_prev = (vm_map_entry_t) new_hole_entry;
+ }
+ } else {
+
+ l_next = hole_entry->vme_next;
+ l_prev = hole_entry->vme_next->vme_prev;
+
+ new_hole_entry->prev = hole_entry;
+ new_hole_entry->next = l_next;
+
+ hole_entry->vme_next = (vm_map_entry_t)new_hole_entry;
+ l_next->vme_prev = (vm_map_entry_t) new_hole_entry;
+ }
+
+ new_hole_entry->start = old_entry->vme_start;
+ new_hole_entry->end = old_entry->vme_end;
+
+ hole_entry = (vm_map_entry_t) new_hole_entry;
+
+ assert(new_hole_entry->start < new_hole_entry->end);
+ }
+
+#if DEBUG
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+
+ SAVE_HINT_HOLE_WRITE(map, (struct vm_map_links*) hole_entry);
+ return;
+}
+
+
+void
+update_holes_on_entry_creation(vm_map_t map, vm_map_entry_t new_entry);
+void
+update_holes_on_entry_creation(vm_map_t map, vm_map_entry_t new_entry)
+{
+
+ vm_map_entry_t hole_entry, next_hole_entry;
+#if DEBUG
+ struct vm_map_entry old_hole_entry;
+ vm_map_entry_t tmp_entry;
+ boolean_t check_map_with_hole_sanity = TRUE;
+#endif /* DEBUG */
+
+ /*
+ * Case A: The entry is aligned exactly with the start and end of the hole.
+ * This will delete the hole.
+ *
+ * Case B: The entry is completely within a hole but NOT aligned with the start/end of the hole.
+ * This will split a hole.
+ *
+ * Case C: The entry overlaps with the hole. The entry could be extending upwards (C1) or downwards (C2).
+ * This will reduce the size of the hole or delete the hole completely if it is smaller than the entry.
+ */
+
+ hole_entry = (vm_map_entry_t) map->holes_list;
+ assert(hole_entry);
+ next_hole_entry = hole_entry->vme_next;
+
+ while (1) {
+
+#if DEBUG
+ /*
+ * If the entry doesn't exist in the RB tree, we are likely dealing with copy maps where
+ * the entries belonging to the copy map are linked into the list of entries silently and
+ * then added to the RB-tree later on.
+ * So sanity checks are useless in that case.
+ */
+ check_map_with_hole_sanity = vm_map_lookup_entry(map, new_entry->vme_start, &tmp_entry);
+#endif /* DEBUG */
+
+ if (hole_entry->vme_start == new_entry->vme_start &&
+ hole_entry->vme_end == new_entry->vme_end) {
+
+ /* Case A */
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ if (hole_entry == (vm_map_entry_t) map->holes_list) {
+
+ if (hole_entry->vme_next == (vm_map_entry_t) map->holes_list) {
+
+ next_hole_entry = vm_map_last_entry(map);
+ assert(next_hole_entry->vme_end >= map->max_offset);
+ }
+ }
+
+ vm_map_delete_hole(map, hole_entry);
+
+#if DEBUG
+ if (check_map_with_hole_sanity)
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+ return;
+
+ } else if (hole_entry->vme_start < new_entry->vme_start &&
+ hole_entry->vme_end > new_entry->vme_end) {
+
+ /* Case B */
+ struct vm_map_links *new_hole_entry = NULL;
+
+ new_hole_entry = zalloc(vm_map_holes_zone);
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ new_hole_entry->prev = hole_entry;
+ new_hole_entry->next = hole_entry->vme_next;
+ hole_entry->vme_next->vme_prev = (vm_map_entry_t)new_hole_entry;
+ hole_entry->vme_next = (vm_map_entry_t)new_hole_entry;
+
+ new_hole_entry->start = new_entry->vme_end;
+ new_hole_entry->end = hole_entry->vme_end;
+ hole_entry->vme_end = new_entry->vme_start;
+
+ assert(hole_entry->vme_start < hole_entry->vme_end);
+ assert(new_hole_entry->start < new_hole_entry->end);
+
+#if DEBUG
+ if (check_map_with_hole_sanity)
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+
+ SAVE_HINT_HOLE_WRITE(map, (struct vm_map_links*) hole_entry);
+ return;
+
+ } else if ((new_entry->vme_start <= hole_entry->vme_start) && (hole_entry->vme_start < new_entry->vme_end)) {
+
+ /*
+ * Case C1: Entry moving upwards and a part/full hole lies within the bounds of the entry.
+ */
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ if (hole_entry->vme_end <= new_entry->vme_end) {
+
+ vm_map_delete_hole(map, hole_entry);
+ } else {
+ hole_entry->vme_start = new_entry->vme_end;
+ SAVE_HINT_HOLE_WRITE(map, (struct vm_map_links*) hole_entry);
+ }
+
+#if DEBUG
+ if (check_map_with_hole_sanity)
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+
+ return;
+
+ } else if ((new_entry->vme_start < hole_entry->vme_end) && (hole_entry->vme_end <= new_entry->vme_end)) {
+
+ /*
+ * Case C2: Entry moving downwards and a part/full hole lies within the bounds of the entry.
+ */
+
+#if DEBUG
+ copy_hole_info(hole_entry, &old_hole_entry);
+#endif /* DEBUG */
+
+ if (hole_entry->vme_start >= new_entry->vme_start) {
+ vm_map_delete_hole(map, hole_entry);
+ } else {
+ hole_entry->vme_end = new_entry->vme_start;
+ SAVE_HINT_HOLE_WRITE(map, (struct vm_map_links*) hole_entry);
+ }
+
+#if DEBUG
+ if (check_map_with_hole_sanity)
+ check_map_sanity(map, &old_hole_entry);
+#endif /* DEBUG */
+
+ return;
+ }
+
+ hole_entry = next_hole_entry;
+ next_hole_entry = hole_entry->vme_next;
+
+ if (hole_entry == (vm_map_entry_t)map->holes_list)
+ break;
+ }
+
+ panic("Illegal action: h1: %p, s:0x%llx, e:0x%llx...h2:%p, s:0x%llx, e:0x%llx...h3:0x%p, s:0x%llx, e:0x%llx\n",
+ hole_entry->vme_prev,
+ (unsigned long long)hole_entry->vme_prev->vme_start,
+ (unsigned long long)hole_entry->vme_prev->vme_end,
+ hole_entry,
+ (unsigned long long)hole_entry->vme_start,
+ (unsigned long long)hole_entry->vme_end,
+ hole_entry->vme_next,
+ (unsigned long long)hole_entry->vme_next->vme_start,
+ (unsigned long long)hole_entry->vme_next->vme_end);
+
+}
+
+void
+update_first_free_rb(vm_map_t map, vm_map_entry_t entry, boolean_t new_entry_creation)
+{
+
+ if (map->holelistenabled) {
+
+ /*
+ * Holes can be used to track ranges all the way up to MACH_VM_MAX_ADDRESS or more (e.g. kernel map).
+ */
+ vm_map_offset_t max_valid_offset = (map->max_offset > MACH_VM_MAX_ADDRESS) ? map->max_offset : MACH_VM_MAX_ADDRESS;
+
+ /*
+ * Clipping an entry will not result in the creation/deletion/modification of
+ * a hole. Those calls pass NULL for their target entry.
+ */
+ if (entry == NULL) {
+ return;
+ }
+
+ /*
+ * Commpage is pinned beyond the map's max offset. That shouldn't affect the
+ * holes within the bounds of the map.
+ */
+ if (vm_map_trunc_page(entry->vme_start, VM_MAP_PAGE_MASK(map)) >= max_valid_offset) {
+ return;
+ }
+
+ /*
+ *
+ * Note:
+ *
+ * - A new entry has already been added to the map
+ * OR
+ * - An older entry has already been deleted from the map
+ *
+ * We are updating the hole list after the fact (except in one special case involving copy maps).
+ *
+ */
+
+ if (new_entry_creation) {
+
+ update_holes_on_entry_creation(map, entry);
+ } else {
+
+ update_holes_on_entry_deletion(map, entry);
+ }
+ }
+}
projects / apple / xnu.git / blobdiff