PGO_NOBLOCKALLOC
const bool blockalloc = memwrite && (flags & PGO_NOBLOCKALLOC) == 0;
#define PAGERFLAGS (PGO_SYNCIO | PGO_NOBLOCKALLOC | PGO_NOTIMESTAMP)
VM_PROT_WRITE, 0, PGO_SYNCIO | PGO_PASTEOF | PGO_NOBLOCKALLOC |
VM_PROT_WRITE, 0, PGO_SYNCIO | PGO_PASTEOF | PGO_NOBLOCKALLOC |
&npages, 0, access_type, umap->advice, flags | PGO_NOBLOCKALLOC |
PGO_SYNCIO|PGO_OVERWRITE|PGO_PASTEOF|PGO_NOBLOCKALLOC|
gpflags |= PGO_OVERWRITE | PGO_NOBLOCKALLOC;
gpflags |= PGO_NOBLOCKALLOC;