xref: /linux-6.15/include/uapi/linux/auto_fs.h (revision 6da2ec56)
1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2 /*
3  * Copyright 1997 Transmeta Corporation - All Rights Reserved
4  * Copyright 1999-2000 Jeremy Fitzhardinge <[email protected]>
5  * Copyright 2005-2006,2013,2017-2018 Ian Kent <[email protected]>
6  *
7  * This file is part of the Linux kernel and is made available under
8  * the terms of the GNU General Public License, version 2, or at your
9  * option, any later version, incorporated herein by reference.
10  *
11  * ----------------------------------------------------------------------- */
12 
13 #ifndef _UAPI_LINUX_AUTO_FS_H
14 #define _UAPI_LINUX_AUTO_FS_H
15 
16 #include <linux/types.h>
17 #include <linux/limits.h>
18 #ifndef __KERNEL__
19 #include <sys/ioctl.h>
20 #endif /* __KERNEL__ */
21 
22 #define AUTOFS_PROTO_VERSION		5
23 #define AUTOFS_MIN_PROTO_VERSION	3
24 #define AUTOFS_MAX_PROTO_VERSION	5
25 
26 #define AUTOFS_PROTO_SUBVERSION		2
27 
28 /*
29  * The wait_queue_token (autofs_wqt_t) is part of a structure which is passed
30  * back to the kernel via ioctl from userspace. On architectures where 32- and
31  * 64-bit userspace binaries can be executed it's important that the size of
32  * autofs_wqt_t stays constant between 32- and 64-bit Linux kernels so that we
33  * do not break the binary ABI interface by changing the structure size.
34  */
35 #if defined(__ia64__) || defined(__alpha__) /* pure 64bit architectures */
36 typedef unsigned long autofs_wqt_t;
37 #else
38 typedef unsigned int autofs_wqt_t;
39 #endif
40 
41 /* Packet types */
42 #define autofs_ptype_missing	0	/* Missing entry (mount request) */
43 #define autofs_ptype_expire	1	/* Expire entry (umount request) */
44 
45 struct autofs_packet_hdr {
46 	int proto_version;		/* Protocol version */
47 	int type;			/* Type of packet */
48 };
49 
50 struct autofs_packet_missing {
51 	struct autofs_packet_hdr hdr;
52 	autofs_wqt_t wait_queue_token;
53 	int len;
54 	char name[NAME_MAX+1];
55 };
56 
57 /* v3 expire (via ioctl) */
58 struct autofs_packet_expire {
59 	struct autofs_packet_hdr hdr;
60 	int len;
61 	char name[NAME_MAX+1];
62 };
63 
64 #define AUTOFS_IOCTL 0x93
65 
66 enum {
67 	AUTOFS_IOC_READY_CMD = 0x60,
68 	AUTOFS_IOC_FAIL_CMD,
69 	AUTOFS_IOC_CATATONIC_CMD,
70 	AUTOFS_IOC_PROTOVER_CMD,
71 	AUTOFS_IOC_SETTIMEOUT_CMD,
72 	AUTOFS_IOC_EXPIRE_CMD,
73 };
74 
75 #define AUTOFS_IOC_READY        _IO(AUTOFS_IOCTL, AUTOFS_IOC_READY_CMD)
76 #define AUTOFS_IOC_FAIL         _IO(AUTOFS_IOCTL, AUTOFS_IOC_FAIL_CMD)
77 #define AUTOFS_IOC_CATATONIC    _IO(AUTOFS_IOCTL, AUTOFS_IOC_CATATONIC_CMD)
78 #define AUTOFS_IOC_PROTOVER     _IOR(AUTOFS_IOCTL, \
79 				     AUTOFS_IOC_PROTOVER_CMD, int)
80 #define AUTOFS_IOC_SETTIMEOUT32 _IOWR(AUTOFS_IOCTL, \
81 				      AUTOFS_IOC_SETTIMEOUT_CMD, \
82 				      compat_ulong_t)
83 #define AUTOFS_IOC_SETTIMEOUT   _IOWR(AUTOFS_IOCTL, \
84 				      AUTOFS_IOC_SETTIMEOUT_CMD, \
85 				      unsigned long)
86 #define AUTOFS_IOC_EXPIRE       _IOR(AUTOFS_IOCTL, \
87 				     AUTOFS_IOC_EXPIRE_CMD, \
88 				     struct autofs_packet_expire)
89 
90 /* autofs version 4 and later definitions */
91 
92 /* Mask for expire behaviour */
93 #define AUTOFS_EXP_IMMEDIATE		1
94 #define AUTOFS_EXP_LEAVES		2
95 
96 #define AUTOFS_TYPE_ANY			0U
97 #define AUTOFS_TYPE_INDIRECT		1U
98 #define AUTOFS_TYPE_DIRECT		2U
99 #define AUTOFS_TYPE_OFFSET		4U
100 
101 static inline void set_autofs_type_indirect(unsigned int *type)
102 {
103 	*type = AUTOFS_TYPE_INDIRECT;
104 }
105 
106 static inline unsigned int autofs_type_indirect(unsigned int type)
107 {
108 	return (type == AUTOFS_TYPE_INDIRECT);
109 }
110 
111 static inline void set_autofs_type_direct(unsigned int *type)
112 {
113 	*type = AUTOFS_TYPE_DIRECT;
114 }
115 
116 static inline unsigned int autofs_type_direct(unsigned int type)
117 {
118 	return (type == AUTOFS_TYPE_DIRECT);
119 }
120 
121 static inline void set_autofs_type_offset(unsigned int *type)
122 {
123 	*type = AUTOFS_TYPE_OFFSET;
124 }
125 
126 static inline unsigned int autofs_type_offset(unsigned int type)
127 {
128 	return (type == AUTOFS_TYPE_OFFSET);
129 }
130 
131 static inline unsigned int autofs_type_trigger(unsigned int type)
132 {
133 	return (type == AUTOFS_TYPE_DIRECT || type == AUTOFS_TYPE_OFFSET);
134 }
135 
136 /*
137  * This isn't really a type as we use it to say "no type set" to
138  * indicate we want to search for "any" mount in the
139  * autofs_dev_ioctl_ismountpoint() device ioctl function.
140  */
141 static inline void set_autofs_type_any(unsigned int *type)
142 {
143 	*type = AUTOFS_TYPE_ANY;
144 }
145 
146 static inline unsigned int autofs_type_any(unsigned int type)
147 {
148 	return (type == AUTOFS_TYPE_ANY);
149 }
150 
151 /* Daemon notification packet types */
152 enum autofs_notify {
153 	NFY_NONE,
154 	NFY_MOUNT,
155 	NFY_EXPIRE
156 };
157 
158 /* Kernel protocol version 4 packet types */
159 
160 /* Expire entry (umount request) */
161 #define autofs_ptype_expire_multi	2
162 
163 /* Kernel protocol version 5 packet types */
164 
165 /* Indirect mount missing and expire requests. */
166 #define autofs_ptype_missing_indirect	3
167 #define autofs_ptype_expire_indirect	4
168 
169 /* Direct mount missing and expire requests */
170 #define autofs_ptype_missing_direct	5
171 #define autofs_ptype_expire_direct	6
172 
173 /* v4 multi expire (via pipe) */
174 struct autofs_packet_expire_multi {
175 	struct autofs_packet_hdr hdr;
176 	autofs_wqt_t wait_queue_token;
177 	int len;
178 	char name[NAME_MAX+1];
179 };
180 
181 union autofs_packet_union {
182 	struct autofs_packet_hdr hdr;
183 	struct autofs_packet_missing missing;
184 	struct autofs_packet_expire expire;
185 	struct autofs_packet_expire_multi expire_multi;
186 };
187 
188 /* autofs v5 common packet struct */
189 struct autofs_v5_packet {
190 	struct autofs_packet_hdr hdr;
191 	autofs_wqt_t wait_queue_token;
192 	__u32 dev;
193 	__u64 ino;
194 	__u32 uid;
195 	__u32 gid;
196 	__u32 pid;
197 	__u32 tgid;
198 	__u32 len;
199 	char name[NAME_MAX+1];
200 };
201 
202 typedef struct autofs_v5_packet autofs_packet_missing_indirect_t;
203 typedef struct autofs_v5_packet autofs_packet_expire_indirect_t;
204 typedef struct autofs_v5_packet autofs_packet_missing_direct_t;
205 typedef struct autofs_v5_packet autofs_packet_expire_direct_t;
206 
207 union autofs_v5_packet_union {
208 	struct autofs_packet_hdr hdr;
209 	struct autofs_v5_packet v5_packet;
210 	autofs_packet_missing_indirect_t missing_indirect;
211 	autofs_packet_expire_indirect_t expire_indirect;
212 	autofs_packet_missing_direct_t missing_direct;
213 	autofs_packet_expire_direct_t expire_direct;
214 };
215 
216 enum {
217 	AUTOFS_IOC_EXPIRE_MULTI_CMD = 0x66, /* AUTOFS_IOC_EXPIRE_CMD + 1 */
218 	AUTOFS_IOC_PROTOSUBVER_CMD,
219 	AUTOFS_IOC_ASKUMOUNT_CMD = 0x70, /* AUTOFS_DEV_IOCTL_VERSION_CMD - 1 */
220 };
221 
222 #define AUTOFS_IOC_EXPIRE_MULTI		_IOW(AUTOFS_IOCTL, \
223 					     AUTOFS_IOC_EXPIRE_MULTI_CMD, int)
224 #define AUTOFS_IOC_PROTOSUBVER		_IOR(AUTOFS_IOCTL, \
225 					     AUTOFS_IOC_PROTOSUBVER_CMD, int)
226 #define AUTOFS_IOC_ASKUMOUNT		_IOR(AUTOFS_IOCTL, \
227 					     AUTOFS_IOC_ASKUMOUNT_CMD, int)
228 
229 #endif /* _UAPI_LINUX_AUTO_FS_H */
230