/* * include/asm-s390/shmparam.h * * S390 version * * Derived from "include/asm-i386/shmparam.h" */ #ifndef _ASM_S390_SHMPARAM_H #define _ASM_S390_SHMPARAM_H /* address range for shared memory attaches if no address passed to shmat() */ #define SHM_RANGE_START 0x50000000 #define SHM_RANGE_END 0x60000000 /* * Format of a swap-entry for shared memory pages currently out in * swap space (see also mm/swap.c). * * SWP_TYPE = SHM_SWP_TYPE * SWP_OFFSET is used as follows: * * bits 0..6 : id of shared memory segment page belongs to (SHM_ID) * bits 7..21: index of page within shared memory segment (SHM_IDX) * (actually fewer bits get used since SHMMAX is so low) */ /* * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and * there is a static array of size SHMMNI. */ #define _SHM_ID_BITS 7 #define SHM_ID_MASK ((1<<_SHM_ID_BITS)-1) #define SHM_IDX_SHIFT (_SHM_ID_BITS) #define _SHM_IDX_BITS 15 #define SHM_IDX_MASK ((1<<_SHM_IDX_BITS)-1) /* * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS). */ #define SHMMAX 0x2000000 /* max shared seg size (bytes) */ /* Try not to change the default shipped SHMMAX - people rely on it */ #define SHMMIN 1 /* really PAGE_SIZE */ /* min shared seg size (bytes) */ #define SHMMNI (1<<_SHM_ID_BITS) /* max num of segs system wide */ #define SHMALL /* max shm system wide (pages) */ \ (1<<(_SHM_IDX_BITS+_SHM_ID_BITS)) #define SHMLBA PAGE_SIZE /* attach addr a multiple of this */ #define SHMSEG SHMMNI /* max shared segs per process */ #endif /* _ASM_S390_SHMPARAM_H */
