Add a memory region type to mammoth

lib/mammoth/src/memory_region.cpp

@@ -0,0 +1,36 @@
+#include "mammoth/memory_region.h"
+
+#include <zcall.h>
+
+#include "mammoth/debug.h"
+
+MappedMemoryRegion MappedMemoryRegion::DirectPhysical(uint64_t paddr,
+                                                      uint64_t size) {
+  uint64_t vmmo_cap;
+  check(ZMemoryObjectCreatePhysical(paddr, size, &vmmo_cap));
+
+  uint64_t vaddr;
+  check(ZAddressSpaceMap(Z_INIT_VMAS_SELF, 0, vmmo_cap, &vaddr));
+
+  return MappedMemoryRegion(vmmo_cap, paddr, vaddr, size);
+}
+
+MappedMemoryRegion MappedMemoryRegion::ContiguousPhysical(uint64_t size) {
+  uint64_t vmmo_cap, paddr;
+  check(ZMemoryObjectCreateContiguous(size, &vmmo_cap, &paddr));
+
+  uint64_t vaddr;
+  check(ZAddressSpaceMap(Z_INIT_VMAS_SELF, 0, vmmo_cap, &vaddr));
+
+  return MappedMemoryRegion(vmmo_cap, paddr, vaddr, size);
+}
+
+MappedMemoryRegion MappedMemoryRegion::Default(uint64_t size) {
+  uint64_t vmmo_cap;
+  check(ZMemoryObjectCreate(size, &vmmo_cap));
+
+  uint64_t vaddr;
+  check(ZAddressSpaceMap(Z_INIT_VMAS_SELF, 0, vmmo_cap, &vaddr));
+
+  return MappedMemoryRegion(vmmo_cap, 0, vaddr, size);
+}