diff options
Diffstat (limited to 'vm/vm_resident.c')
| -rw-r--r-- | vm/vm_resident.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/vm/vm_resident.c b/vm/vm_resident.c index e276fe68..e3e34dc3 100644 --- a/vm/vm_resident.c +++ b/vm/vm_resident.c @@ -771,6 +771,15 @@ vm_page_t vm_page_grab(void) simple_lock(&vm_page_queue_free_lock); + /* + * XXX Mach has many modules that merely assume memory is + * directly mapped in kernel space. Instead of updating all + * users, we assume those which need specific physical memory + * properties will wire down their pages, either because + * they can't be paged (not part of an object), or with + * explicit VM calls. The strategy is then to let memory + * pressure balance the physical segments with pageable pages. + */ mem = vm_page_alloc_pa(0, VM_PAGE_SEL_DIRECTMAP, VM_PT_KERNEL); if (mem == NULL) { |