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Diffstat (limited to 'include/uapi/linux/shm.h')
| -rw-r--r-- | include/uapi/linux/shm.h | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/include/uapi/linux/shm.h b/include/uapi/linux/shm.h new file mode 100644 index 000000000..8d1f17a4e --- /dev/null +++ b/include/uapi/linux/shm.h @@ -0,0 +1,111 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef _UAPI_LINUX_SHM_H_ +#define _UAPI_LINUX_SHM_H_ + +#include <linux/ipc.h> +#include <linux/errno.h> +#include <asm-generic/hugetlb_encode.h> +#ifndef __KERNEL__ +#include <unistd.h> +#endif + +/* + * SHMMNI, SHMMAX and SHMALL are default upper limits which can be + * modified by sysctl. The SHMMAX and SHMALL values have been chosen to + * be as large possible without facilitating scenarios where userspace + * causes overflows when adjusting the limits via operations of the form + * "retrieve current limit; add X; update limit". It is therefore not + * advised to make SHMMAX and SHMALL any larger. These limits are + * suitable for both 32 and 64-bit systems. + */ +#define SHMMIN 1 /* min shared seg size (bytes) */ +#define SHMMNI 4096 /* max num of segs system wide */ +#define SHMMAX (ULONG_MAX - (1UL << 24)) /* max shared seg size (bytes) */ +#define SHMALL (ULONG_MAX - (1UL << 24)) /* max shm system wide (pages) */ +#define SHMSEG SHMMNI /* max shared segs per process */ + +/* Obsolete, used only for backwards compatibility and libc5 compiles */ +struct shmid_ds { + struct ipc_perm shm_perm; /* operation perms */ + int shm_segsz; /* size of segment (bytes) */ + __kernel_old_time_t shm_atime; /* last attach time */ + __kernel_old_time_t shm_dtime; /* last detach time */ + __kernel_old_time_t shm_ctime; /* last change time */ + __kernel_ipc_pid_t shm_cpid; /* pid of creator */ + __kernel_ipc_pid_t shm_lpid; /* pid of last operator */ + unsigned short shm_nattch; /* no. of current attaches */ + unsigned short shm_unused; /* compatibility */ + void *shm_unused2; /* ditto - used by DIPC */ + void *shm_unused3; /* unused */ +}; + +/* Include the definition of shmid64_ds and shminfo64 */ +#include <asm/shmbuf.h> + +/* + * shmget() shmflg values. + */ +/* The bottom nine bits are the same as open(2) mode flags */ +#define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */ +#define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */ +/* Bits 9 & 10 are IPC_CREAT and IPC_EXCL */ +#define SHM_HUGETLB 04000 /* segment will use huge TLB pages */ +#define SHM_NORESERVE 010000 /* don't check for reservations */ + +/* + * Huge page size encoding when SHM_HUGETLB is specified, and a huge page + * size other than the default is desired. See hugetlb_encode.h + */ +#define SHM_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT +#define SHM_HUGE_MASK HUGETLB_FLAG_ENCODE_MASK + +#define SHM_HUGE_64KB HUGETLB_FLAG_ENCODE_64KB +#define SHM_HUGE_512KB HUGETLB_FLAG_ENCODE_512KB +#define SHM_HUGE_1MB HUGETLB_FLAG_ENCODE_1MB +#define SHM_HUGE_2MB HUGETLB_FLAG_ENCODE_2MB +#define SHM_HUGE_8MB HUGETLB_FLAG_ENCODE_8MB +#define SHM_HUGE_16MB HUGETLB_FLAG_ENCODE_16MB +#define SHM_HUGE_32MB HUGETLB_FLAG_ENCODE_32MB +#define SHM_HUGE_256MB HUGETLB_FLAG_ENCODE_256MB +#define SHM_HUGE_512MB HUGETLB_FLAG_ENCODE_512MB +#define SHM_HUGE_1GB HUGETLB_FLAG_ENCODE_1GB +#define SHM_HUGE_2GB HUGETLB_FLAG_ENCODE_2GB +#define SHM_HUGE_16GB HUGETLB_FLAG_ENCODE_16GB + +/* + * shmat() shmflg values + */ +#define SHM_RDONLY 010000 /* read-only access */ +#define SHM_RND 020000 /* round attach address to SHMLBA boundary */ +#define SHM_REMAP 040000 /* take-over region on attach */ +#define SHM_EXEC 0100000 /* execution access */ + +/* super user shmctl commands */ +#define SHM_LOCK 11 +#define SHM_UNLOCK 12 + +/* ipcs ctl commands */ +#define SHM_STAT 13 +#define SHM_INFO 14 +#define SHM_STAT_ANY 15 + +/* Obsolete, used only for backwards compatibility */ +struct shminfo { + int shmmax; + int shmmin; + int shmmni; + int shmseg; + int shmall; +}; + +struct shm_info { + int used_ids; + __kernel_ulong_t shm_tot; /* total allocated shm */ + __kernel_ulong_t shm_rss; /* total resident shm */ + __kernel_ulong_t shm_swp; /* total swapped shm */ + __kernel_ulong_t swap_attempts; + __kernel_ulong_t swap_successes; +}; + + +#endif /* _UAPI_LINUX_SHM_H_ */ |