void
kmem_submap(
vm_map_t map,
vm_map_t parent,
vm_offset_t *min,
vm_offset_t *max,
vm_size_t size,
boolean_t pageable)
{
vm_offset_t addr;
kern_return_t kr;
size = round_page(size);
/*
* Need reference on submap object because it is internal
* to the vm_system. vm_object_enter will never be called
* on it (usual source of reference for vm_map_enter).
*/
vm_object_reference(vm_submap_object);
addr = vm_map_min(parent);
kr = vm_map_enter(parent, &addr, size,
(vm_offset_t) 0, TRUE,
vm_submap_object, (vm_offset_t) 0, FALSE,
VM_PROT_DEFAULT, VM_PROT_ALL, VM_INHERIT_DEFAULT);
if (kr != KERN_SUCCESS)
panic("kmem_submap");
pmap_reference(vm_map_pmap(parent));
vm_map_setup(map, vm_map_pmap(parent), addr, addr + size, pageable);
kr = vm_map_submap(parent, addr, addr + size, map);
if (kr != KERN_SUCCESS)
panic("kmem_submap");
*min = addr;
*max = addr + size;
}
/*
* kmem_suballoc:
*
* Allocates a map to manage a subrange
* of the kernel virtual address space.
*
* Arguments are as follows:
*
* parent Map to take range from
* min, max Returned endpoints of map
* size Size of range to find
* superpage_align Request that min is superpage aligned
*/
vm_map_t
kmem_suballoc(vm_map_t parent, vm_offset_t *min, vm_offset_t *max,
vm_size_t size, boolean_t superpage_align)
{
int ret;
vm_map_t result;
size = round_page(size);
*min = vm_map_min(parent);
ret = vm_map_find(parent, NULL, 0, min, size, 0, superpage_align ?
VMFS_SUPER_SPACE : VMFS_ANY_SPACE, VM_PROT_ALL, VM_PROT_ALL,
MAP_ACC_NO_CHARGE);
if (ret != KERN_SUCCESS)
panic("kmem_suballoc: bad status return of %d", ret);
*max = *min + size;
result = vm_map_create(vm_map_pmap(parent), *min, *max);
if (result == NULL)
panic("kmem_suballoc: cannot create submap");
if (vm_map_submap(parent, *min, *max, result) != KERN_SUCCESS)
panic("kmem_suballoc: unable to change range to submap");
return (result);
}
