Что за константа MODULE_ADDR

/* The kernel image occupies 0x4000000 to 0x6000000 (4MB --> 96MB).
 * The page copy blockops can use 0x6000000 to 0x8000000.
 * The TSB is mapped in the 0x8000000 to 0xa000000 range.
 * The PROM resides in an area spanning 0xf0000000 to 0x100000000.
 * The vmalloc area spans 0x100000000 to 0x200000000.
 * Since modules need to be in the lowest 32-bits of the address space,
 * we place them right before the OBP area from 0x10000000 to 0xf0000000.
 * There is a single static kernel PMD which maps from 0x0 to address
 * 0x400000000.
 */
#define TLBTEMP_BASE            _AC(0x0000000006000000,UL)
#define TSBMAP_BASE             _AC(0x0000000008000000,UL)
#define MODULES_VADDR           _AC(0x0000000010000000,UL)
#define MODULES_LEN             _AC(0x00000000e0000000,UL)
#define MODULES_END             _AC(0x00000000f0000000,UL)
#define LOW_OBP_ADDRESS         _AC(0x00000000f0000000,UL)
#define HI_OBP_ADDRESS          _AC(0x0000000100000000,UL)
#define VMALLOC_START           _AC(0x0000000100000000,UL)
#define VMALLOC_END             _AC(0x0000010000000000,UL)
#define VMEMMAP_BASE            _AC(0x0000010000000000,UL)