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-rw-r--r--include/uapi/linux/shm.h80
1 files changed, 80 insertions, 0 deletions
diff --git a/include/uapi/linux/shm.h b/include/uapi/linux/shm.h
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+++ b/include/uapi/linux/shm.h
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+#ifndef _UAPI_LINUX_SHM_H_
+#define _UAPI_LINUX_SHM_H_
+
+#include <linux/ipc.h>
+#include <linux/errno.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_time_t shm_atime; /* last attach time */
+ __kernel_time_t shm_dtime; /* last detach time */
+ __kernel_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>
+
+/* permission flag for shmget */
+#define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */
+#define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */
+
+/* mode for attach */
+#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
+
+/* 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_ */