xref: /linux/include/uapi/linux/fcntl.h (revision 06a130e42a5bfc84795464bff023bff4c16f58c5)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _UAPI_LINUX_FCNTL_H
3 #define _UAPI_LINUX_FCNTL_H
4 
5 #include <asm/fcntl.h>
6 #include <linux/openat2.h>
7 
8 #define F_SETLEASE	(F_LINUX_SPECIFIC_BASE + 0)
9 #define F_GETLEASE	(F_LINUX_SPECIFIC_BASE + 1)
10 
11 /*
12  * Request nofications on a directory.
13  * See below for events that may be notified.
14  */
15 #define F_NOTIFY	(F_LINUX_SPECIFIC_BASE + 2)
16 
17 #define F_DUPFD_QUERY	(F_LINUX_SPECIFIC_BASE + 3)
18 
19 /* Was the file just created? */
20 #define F_CREATED_QUERY	(F_LINUX_SPECIFIC_BASE + 4)
21 
22 /*
23  * Cancel a blocking posix lock; internal use only until we expose an
24  * asynchronous lock api to userspace:
25  */
26 #define F_CANCELLK	(F_LINUX_SPECIFIC_BASE + 5)
27 
28 /* Create a file descriptor with FD_CLOEXEC set. */
29 #define F_DUPFD_CLOEXEC	(F_LINUX_SPECIFIC_BASE + 6)
30 
31 /*
32  * Set and get of pipe page size array
33  */
34 #define F_SETPIPE_SZ	(F_LINUX_SPECIFIC_BASE + 7)
35 #define F_GETPIPE_SZ	(F_LINUX_SPECIFIC_BASE + 8)
36 
37 /*
38  * Set/Get seals
39  */
40 #define F_ADD_SEALS	(F_LINUX_SPECIFIC_BASE + 9)
41 #define F_GET_SEALS	(F_LINUX_SPECIFIC_BASE + 10)
42 
43 /*
44  * Types of seals
45  */
46 #define F_SEAL_SEAL	0x0001	/* prevent further seals from being set */
47 #define F_SEAL_SHRINK	0x0002	/* prevent file from shrinking */
48 #define F_SEAL_GROW	0x0004	/* prevent file from growing */
49 #define F_SEAL_WRITE	0x0008	/* prevent writes */
50 #define F_SEAL_FUTURE_WRITE	0x0010  /* prevent future writes while mapped */
51 #define F_SEAL_EXEC	0x0020  /* prevent chmod modifying exec bits */
52 /* (1U << 31) is reserved for signed error codes */
53 
54 /*
55  * Set/Get write life time hints. {GET,SET}_RW_HINT operate on the
56  * underlying inode, while {GET,SET}_FILE_RW_HINT operate only on
57  * the specific file.
58  */
59 #define F_GET_RW_HINT		(F_LINUX_SPECIFIC_BASE + 11)
60 #define F_SET_RW_HINT		(F_LINUX_SPECIFIC_BASE + 12)
61 #define F_GET_FILE_RW_HINT	(F_LINUX_SPECIFIC_BASE + 13)
62 #define F_SET_FILE_RW_HINT	(F_LINUX_SPECIFIC_BASE + 14)
63 
64 /*
65  * Valid hint values for F_{GET,SET}_RW_HINT. 0 is "not set", or can be
66  * used to clear any hints previously set.
67  */
68 #define RWH_WRITE_LIFE_NOT_SET	0
69 #define RWH_WRITE_LIFE_NONE	1
70 #define RWH_WRITE_LIFE_SHORT	2
71 #define RWH_WRITE_LIFE_MEDIUM	3
72 #define RWH_WRITE_LIFE_LONG	4
73 #define RWH_WRITE_LIFE_EXTREME	5
74 
75 /*
76  * The originally introduced spelling is remained from the first
77  * versions of the patch set that introduced the feature, see commit
78  * v4.13-rc1~212^2~51.
79  */
80 #define RWF_WRITE_LIFE_NOT_SET	RWH_WRITE_LIFE_NOT_SET
81 
82 /*
83  * Types of directory notifications that may be requested.
84  */
85 #define DN_ACCESS	0x00000001	/* File accessed */
86 #define DN_MODIFY	0x00000002	/* File modified */
87 #define DN_CREATE	0x00000004	/* File created */
88 #define DN_DELETE	0x00000008	/* File removed */
89 #define DN_RENAME	0x00000010	/* File renamed */
90 #define DN_ATTRIB	0x00000020	/* File changed attibutes */
91 #define DN_MULTISHOT	0x80000000	/* Don't remove notifier */
92 
93 #define AT_FDCWD		-100    /* Special value for dirfd used to
94 					   indicate openat should use the
95 					   current working directory. */
96 
97 
98 /* Generic flags for the *at(2) family of syscalls. */
99 
100 /* Reserved for per-syscall flags	0xff. */
101 #define AT_SYMLINK_NOFOLLOW		0x100   /* Do not follow symbolic
102 						   links. */
103 /* Reserved for per-syscall flags	0x200 */
104 #define AT_SYMLINK_FOLLOW		0x400   /* Follow symbolic links. */
105 #define AT_NO_AUTOMOUNT			0x800	/* Suppress terminal automount
106 						   traversal. */
107 #define AT_EMPTY_PATH			0x1000	/* Allow empty relative
108 						   pathname to operate on dirfd
109 						   directly. */
110 /*
111  * These flags are currently statx(2)-specific, but they could be made generic
112  * in the future and so they should not be used for other per-syscall flags.
113  */
114 #define AT_STATX_SYNC_TYPE		0x6000	/* Type of synchronisation required from statx() */
115 #define AT_STATX_SYNC_AS_STAT		0x0000	/* - Do whatever stat() does */
116 #define AT_STATX_FORCE_SYNC		0x2000	/* - Force the attributes to be sync'd with the server */
117 #define AT_STATX_DONT_SYNC		0x4000	/* - Don't sync attributes with the server */
118 
119 #define AT_RECURSIVE			0x8000	/* Apply to the entire subtree */
120 
121 /*
122  * Per-syscall flags for the *at(2) family of syscalls.
123  *
124  * These are flags that are so syscall-specific that a user passing these flags
125  * to the wrong syscall is so "clearly wrong" that we can safely call such
126  * usage "undefined behaviour".
127  *
128  * For example, the constants AT_REMOVEDIR and AT_EACCESS have the same value.
129  * AT_EACCESS is meaningful only to faccessat, while AT_REMOVEDIR is meaningful
130  * only to unlinkat. The two functions do completely different things and
131  * therefore, the flags can be allowed to overlap. For example, passing
132  * AT_REMOVEDIR to faccessat would be undefined behavior and thus treating it
133  * equivalent to AT_EACCESS is valid undefined behavior.
134  *
135  * Note for implementers: When picking a new per-syscall AT_* flag, try to
136  * reuse already existing flags first. This leaves us with as many unused bits
137  * as possible, so we can use them for generic bits in the future if necessary.
138  */
139 
140 /* Flags for renameat2(2) (must match legacy RENAME_* flags). */
141 #define AT_RENAME_NOREPLACE	0x0001
142 #define AT_RENAME_EXCHANGE	0x0002
143 #define AT_RENAME_WHITEOUT	0x0004
144 
145 /* Flag for faccessat(2). */
146 #define AT_EACCESS		0x200	/* Test access permitted for
147                                            effective IDs, not real IDs.  */
148 /* Flag for unlinkat(2). */
149 #define AT_REMOVEDIR		0x200   /* Remove directory instead of
150                                            unlinking file.  */
151 /* Flags for name_to_handle_at(2). */
152 #define AT_HANDLE_FID		0x200	/* File handle is needed to compare
153 					   object identity and may not be
154 					   usable with open_by_handle_at(2). */
155 #define AT_HANDLE_MNT_ID_UNIQUE	0x001	/* Return the u64 unique mount ID. */
156 
157 #if defined(__KERNEL__)
158 #define AT_GETATTR_NOSEC	0x80000000
159 #endif
160 
161 #endif /* _UAPI_LINUX_FCNTL_H */
162