1 | /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ |
2 | #ifndef _UAPI_LINUX_SHM_H_ |
3 | #define _UAPI_LINUX_SHM_H_ |
4 | |
5 | #include <linux/ipc.h> |
6 | #include <linux/errno.h> |
7 | #include <asm-generic/hugetlb_encode.h> |
8 | #ifndef __KERNEL__ |
9 | #include <unistd.h> |
10 | #endif |
11 | |
12 | /* |
13 | * SHMMNI, SHMMAX and SHMALL are default upper limits which can be |
14 | * modified by sysctl. The SHMMAX and SHMALL values have been chosen to |
15 | * be as large possible without facilitating scenarios where userspace |
16 | * causes overflows when adjusting the limits via operations of the form |
17 | * "retrieve current limit; add X; update limit". It is therefore not |
18 | * advised to make SHMMAX and SHMALL any larger. These limits are |
19 | * suitable for both 32 and 64-bit systems. |
20 | */ |
21 | #define SHMMIN 1 /* min shared seg size (bytes) */ |
22 | #define SHMMNI 4096 /* max num of segs system wide */ |
23 | #define SHMMAX (ULONG_MAX - (1UL << 24)) /* max shared seg size (bytes) */ |
24 | #define SHMALL (ULONG_MAX - (1UL << 24)) /* max shm system wide (pages) */ |
25 | #define SHMSEG SHMMNI /* max shared segs per process */ |
26 | |
27 | /* Obsolete, used only for backwards compatibility and libc5 compiles */ |
28 | struct shmid_ds { |
29 | struct ipc_perm shm_perm; /* operation perms */ |
30 | int shm_segsz; /* size of segment (bytes) */ |
31 | __kernel_old_time_t shm_atime; /* last attach time */ |
32 | __kernel_old_time_t shm_dtime; /* last detach time */ |
33 | __kernel_old_time_t shm_ctime; /* last change time */ |
34 | __kernel_ipc_pid_t shm_cpid; /* pid of creator */ |
35 | __kernel_ipc_pid_t shm_lpid; /* pid of last operator */ |
36 | unsigned short shm_nattch; /* no. of current attaches */ |
37 | unsigned short shm_unused; /* compatibility */ |
38 | void *shm_unused2; /* ditto - used by DIPC */ |
39 | void *shm_unused3; /* unused */ |
40 | }; |
41 | |
42 | /* Include the definition of shmid64_ds and shminfo64 */ |
43 | #include <asm/shmbuf.h> |
44 | |
45 | /* |
46 | * shmget() shmflg values. |
47 | */ |
48 | /* The bottom nine bits are the same as open(2) mode flags */ |
49 | #define SHM_R 0400 /* or S_IRUGO from <linux/stat.h> */ |
50 | #define SHM_W 0200 /* or S_IWUGO from <linux/stat.h> */ |
51 | /* Bits 9 & 10 are IPC_CREAT and IPC_EXCL */ |
52 | #define SHM_HUGETLB 04000 /* segment will use huge TLB pages */ |
53 | #define SHM_NORESERVE 010000 /* don't check for reservations */ |
54 | |
55 | /* |
56 | * Huge page size encoding when SHM_HUGETLB is specified, and a huge page |
57 | * size other than the default is desired. See hugetlb_encode.h |
58 | */ |
59 | #define SHM_HUGE_SHIFT HUGETLB_FLAG_ENCODE_SHIFT |
60 | #define SHM_HUGE_MASK HUGETLB_FLAG_ENCODE_MASK |
61 | |
62 | #define SHM_HUGE_64KB HUGETLB_FLAG_ENCODE_64KB |
63 | #define SHM_HUGE_512KB HUGETLB_FLAG_ENCODE_512KB |
64 | #define SHM_HUGE_1MB HUGETLB_FLAG_ENCODE_1MB |
65 | #define SHM_HUGE_2MB HUGETLB_FLAG_ENCODE_2MB |
66 | #define SHM_HUGE_8MB HUGETLB_FLAG_ENCODE_8MB |
67 | #define SHM_HUGE_16MB HUGETLB_FLAG_ENCODE_16MB |
68 | #define SHM_HUGE_32MB HUGETLB_FLAG_ENCODE_32MB |
69 | #define SHM_HUGE_256MB HUGETLB_FLAG_ENCODE_256MB |
70 | #define SHM_HUGE_512MB HUGETLB_FLAG_ENCODE_512MB |
71 | #define SHM_HUGE_1GB HUGETLB_FLAG_ENCODE_1GB |
72 | #define SHM_HUGE_2GB HUGETLB_FLAG_ENCODE_2GB |
73 | #define SHM_HUGE_16GB HUGETLB_FLAG_ENCODE_16GB |
74 | |
75 | /* |
76 | * shmat() shmflg values |
77 | */ |
78 | #define SHM_RDONLY 010000 /* read-only access */ |
79 | #define SHM_RND 020000 /* round attach address to SHMLBA boundary */ |
80 | #define SHM_REMAP 040000 /* take-over region on attach */ |
81 | #define SHM_EXEC 0100000 /* execution access */ |
82 | |
83 | /* super user shmctl commands */ |
84 | #define SHM_LOCK 11 |
85 | #define SHM_UNLOCK 12 |
86 | |
87 | /* ipcs ctl commands */ |
88 | #define SHM_STAT 13 |
89 | #define SHM_INFO 14 |
90 | #define SHM_STAT_ANY 15 |
91 | |
92 | /* Obsolete, used only for backwards compatibility */ |
93 | struct shminfo { |
94 | int shmmax; |
95 | int shmmin; |
96 | int shmmni; |
97 | int shmseg; |
98 | int shmall; |
99 | }; |
100 | |
101 | struct shm_info { |
102 | int used_ids; |
103 | __kernel_ulong_t shm_tot; /* total allocated shm */ |
104 | __kernel_ulong_t ; /* total resident shm */ |
105 | __kernel_ulong_t shm_swp; /* total swapped shm */ |
106 | __kernel_ulong_t swap_attempts; |
107 | __kernel_ulong_t swap_successes; |
108 | }; |
109 | |
110 | |
111 | #endif /* _UAPI_LINUX_SHM_H_ */ |
112 | |