[PATCH 05/11] adjust range when changing memory pageability

[Luca Dariz]

* vm/vm_map.c: use actual limits instead of min/max boundaries to
  change pageability of the currently mapped memory.

This caused the initial vm_wire_all(host, task VM_WIRE_ALL) in glibc
startup to fail with KERN_NO_SPACE.
---
 vm/vm_map.c | 31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/vm/vm_map.c b/vm/vm_map.c
index 26e18676..e454bb2a 100644
--- a/vm/vm_map.c
+++ b/vm/vm_map.c
@@ -1829,6 +1829,30 @@ kern_return_t vm_map_pageable(
        return(KERN_SUCCESS);
 }
 
+/* Update pageability of all the memory currently in the map.
+ * The map must be locked, and protection mismatch will not be checked, see
+ * vm_map_pageable().
+ */
+static kern_return_t
+vm_map_pageable_current(vm_map_t map, vm_prot_t access_type)
+{
+       struct rbtree_node *node;
+       vm_offset_t min_address, max_address;
+
+       node = rbtree_first(&map->hdr.tree);
+       min_address = rbtree_entry(node, struct vm_map_entry,
+                                  tree_node)->vme_start;
+
+       node = rbtree_last(&map->hdr.tree);
+       max_address = rbtree_entry(node, struct vm_map_entry,
+                                  tree_node)->vme_end;
+
+       /* Returns with the map read-locked if successful */
+       return vm_map_pageable(map, min_address, max_address,access_type,
+                              FALSE, FALSE);
+}
+
+
 /*
  *     vm_map_pageable_all:
  *
@@ -1859,8 +1883,7 @@ vm_map_pageable_all(struct vm_map *map, vm_wire_t flags)
                map->wiring_required = FALSE;
 
                /* Returns with the map read-locked if successful */
-               kr = vm_map_pageable(map, map->min_offset, map->max_offset,
-                                    VM_PROT_NONE, FALSE, FALSE);
+               kr = vm_map_pageable_current(map, VM_PROT_NONE);
                vm_map_unlock(map);
                return kr;
        }
@@ -1873,9 +1896,7 @@ vm_map_pageable_all(struct vm_map *map, vm_wire_t flags)
 
        if (flags & VM_WIRE_CURRENT) {
                /* Returns with the map read-locked if successful */
-               kr = vm_map_pageable(map, map->min_offset, map->max_offset,
-                                    VM_PROT_READ | VM_PROT_WRITE,
-                                    FALSE, FALSE);
+               kr = vm_map_pageable_current(map, VM_PROT_READ | VM_PROT_WRITE);
 
                if (kr != KERN_SUCCESS) {
                        if (flags & VM_WIRE_FUTURE) {
-- 
2.39.2