1 #ifndef _UAPI_LINUX_SHM_H_ 2 #define _UAPI_LINUX_SHM_H_ 3 4 #include <linux/ipc.h> 5 #include <linux/errno.h> 6 #ifndef __KERNEL__ 7 #include <unistd.h> 8 #endif 9 10 /* 11 * SHMMNI, SHMMAX and SHMALL are default upper limits which can be 12 * modified by sysctl. The SHMMAX and SHMALL values have been chosen to 13 * be as large possible without facilitating scenarios where userspace 14 * causes overflows when adjusting the limits via operations of the form 15 * "retrieve current limit; add X; update limit". It is therefore not 16 * advised to make SHMMAX and SHMALL any larger. These limits are 17 * suitable for both 32 and 64-bit systems. 18 */ 19 #define SHMMIN 1 /* min shared seg size (bytes) */ 20 #define SHMMNI 4096 /* max num of segs system wide */ 21 #define SHMMAX (ULONG_MAX - (1UL << 24)) /* max shared seg size (bytes) */ 22 #define SHMALL (ULONG_MAX - (1UL << 24)) /* max shm system wide (pages) */ 23 #define SHMSEG SHMMNI /* max shared segs per process */ 24 25 /* Obsolete, used only for backwards compatibility and libc5 compiles */ 26 struct shmid_ds { 27 struct ipc_perm shm_perm; /* operation perms */ 28 int shm_segsz; /* size of segment (bytes) */ 29 __kernel_time_t shm_atime; /* last attach time */ 30 __kernel_time_t shm_dtime; /* last detach time */ 31 __kernel_time_t shm_ctime; /* last change time */ 32 __kernel_ipc_pid_t shm_cpid; /* pid of creator */ 33 __kernel_ipc_pid_t shm_lpid; /* pid of last operator */ 34 unsigned short shm_nattch; /* no. of current attaches */ 35 unsigned short shm_unused; /* compatibility */ 36 void *shm_unused2; /* ditto - used by DIPC */ 37 void *shm_unused3; /* unused */ 38 }; 39 40 /* Include the definition of shmid64_ds and shminfo64 */ 41 #include <asm/shmbuf.h> 42 43 /* permission flag for shmget */ 44 #define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */ 45 #define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */ 46 47 /* mode for attach */ 48 #define SHM_RDONLY 010000 /* read-only access */ 49 #define SHM_RND 020000 /* round attach address to SHMLBA boundary */ 50 #define SHM_REMAP 040000 /* take-over region on attach */ 51 #define SHM_EXEC 0100000 /* execution access */ 52 53 /* super user shmctl commands */ 54 #define SHM_LOCK 11 55 #define SHM_UNLOCK 12 56 57 /* ipcs ctl commands */ 58 #define SHM_STAT 13 59 #define SHM_INFO 14 60 61 /* Obsolete, used only for backwards compatibility */ 62 struct shminfo { 63 int shmmax; 64 int shmmin; 65 int shmmni; 66 int shmseg; 67 int shmall; 68 }; 69 70 struct shm_info { 71 int used_ids; 72 __kernel_ulong_t shm_tot; /* total allocated shm */ 73 __kernel_ulong_t shm_rss; /* total resident shm */ 74 __kernel_ulong_t shm_swp; /* total swapped shm */ 75 __kernel_ulong_t swap_attempts; 76 __kernel_ulong_t swap_successes; 77 }; 78 79 80 #endif /* _UAPI_LINUX_SHM_H_ */ 81
