xref: /linux/include/uapi/linux/auto_fs.h (revision 8f72c31f45a575d156cfe964099b4cfcc02e03eb)
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 <jeremy@goop.org>
5  * Copyright 2005-2006,2013,2017-2018 Ian Kent <raven@themaw.net>
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		6
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_NORMAL		0x00
94 #define AUTOFS_EXP_IMMEDIATE		0x01
95 #define AUTOFS_EXP_LEAVES		0x02
96 #define AUTOFS_EXP_FORCED		0x04
97 
98 #define AUTOFS_TYPE_ANY			0U
99 #define AUTOFS_TYPE_INDIRECT		1U
100 #define AUTOFS_TYPE_DIRECT		2U
101 #define AUTOFS_TYPE_OFFSET		4U
102 
set_autofs_type_indirect(unsigned int * type)103 static inline void set_autofs_type_indirect(unsigned int *type)
104 {
105 	*type = AUTOFS_TYPE_INDIRECT;
106 }
107 
autofs_type_indirect(unsigned int type)108 static inline unsigned int autofs_type_indirect(unsigned int type)
109 {
110 	return (type == AUTOFS_TYPE_INDIRECT);
111 }
112 
set_autofs_type_direct(unsigned int * type)113 static inline void set_autofs_type_direct(unsigned int *type)
114 {
115 	*type = AUTOFS_TYPE_DIRECT;
116 }
117 
autofs_type_direct(unsigned int type)118 static inline unsigned int autofs_type_direct(unsigned int type)
119 {
120 	return (type == AUTOFS_TYPE_DIRECT);
121 }
122 
set_autofs_type_offset(unsigned int * type)123 static inline void set_autofs_type_offset(unsigned int *type)
124 {
125 	*type = AUTOFS_TYPE_OFFSET;
126 }
127 
autofs_type_offset(unsigned int type)128 static inline unsigned int autofs_type_offset(unsigned int type)
129 {
130 	return (type == AUTOFS_TYPE_OFFSET);
131 }
132 
autofs_type_trigger(unsigned int type)133 static inline unsigned int autofs_type_trigger(unsigned int type)
134 {
135 	return (type == AUTOFS_TYPE_DIRECT || type == AUTOFS_TYPE_OFFSET);
136 }
137 
138 /*
139  * This isn't really a type as we use it to say "no type set" to
140  * indicate we want to search for "any" mount in the
141  * autofs_dev_ioctl_ismountpoint() device ioctl function.
142  */
set_autofs_type_any(unsigned int * type)143 static inline void set_autofs_type_any(unsigned int *type)
144 {
145 	*type = AUTOFS_TYPE_ANY;
146 }
147 
autofs_type_any(unsigned int type)148 static inline unsigned int autofs_type_any(unsigned int type)
149 {
150 	return (type == AUTOFS_TYPE_ANY);
151 }
152 
153 /* Daemon notification packet types */
154 enum autofs_notify {
155 	NFY_NONE,
156 	NFY_MOUNT,
157 	NFY_EXPIRE
158 };
159 
160 /* Kernel protocol version 4 packet types */
161 
162 /* Expire entry (umount request) */
163 #define autofs_ptype_expire_multi	2
164 
165 /* Kernel protocol version 5 packet types */
166 
167 /* Indirect mount missing and expire requests. */
168 #define autofs_ptype_missing_indirect	3
169 #define autofs_ptype_expire_indirect	4
170 
171 /* Direct mount missing and expire requests */
172 #define autofs_ptype_missing_direct	5
173 #define autofs_ptype_expire_direct	6
174 
175 /* v4 multi expire (via pipe) */
176 struct autofs_packet_expire_multi {
177 	struct autofs_packet_hdr hdr;
178 	autofs_wqt_t wait_queue_token;
179 	int len;
180 	char name[NAME_MAX+1];
181 };
182 
183 union autofs_packet_union {
184 	struct autofs_packet_hdr hdr;
185 	struct autofs_packet_missing missing;
186 	struct autofs_packet_expire expire;
187 	struct autofs_packet_expire_multi expire_multi;
188 };
189 
190 /* autofs v5 common packet struct */
191 struct autofs_v5_packet {
192 	struct autofs_packet_hdr hdr;
193 	autofs_wqt_t wait_queue_token;
194 	__u32 dev;
195 	__u64 ino;
196 	__u32 uid;
197 	__u32 gid;
198 	__u32 pid;
199 	__u32 tgid;
200 	__u32 len;
201 	char name[NAME_MAX+1];
202 };
203 
204 typedef struct autofs_v5_packet autofs_packet_missing_indirect_t;
205 typedef struct autofs_v5_packet autofs_packet_expire_indirect_t;
206 typedef struct autofs_v5_packet autofs_packet_missing_direct_t;
207 typedef struct autofs_v5_packet autofs_packet_expire_direct_t;
208 
209 union autofs_v5_packet_union {
210 	struct autofs_packet_hdr hdr;
211 	struct autofs_v5_packet v5_packet;
212 	autofs_packet_missing_indirect_t missing_indirect;
213 	autofs_packet_expire_indirect_t expire_indirect;
214 	autofs_packet_missing_direct_t missing_direct;
215 	autofs_packet_expire_direct_t expire_direct;
216 };
217 
218 enum {
219 	AUTOFS_IOC_EXPIRE_MULTI_CMD = 0x66, /* AUTOFS_IOC_EXPIRE_CMD + 1 */
220 	AUTOFS_IOC_PROTOSUBVER_CMD,
221 	AUTOFS_IOC_ASKUMOUNT_CMD = 0x70, /* AUTOFS_DEV_IOCTL_VERSION_CMD - 1 */
222 };
223 
224 #define AUTOFS_IOC_EXPIRE_MULTI		_IOW(AUTOFS_IOCTL, \
225 					     AUTOFS_IOC_EXPIRE_MULTI_CMD, int)
226 #define AUTOFS_IOC_PROTOSUBVER		_IOR(AUTOFS_IOCTL, \
227 					     AUTOFS_IOC_PROTOSUBVER_CMD, int)
228 #define AUTOFS_IOC_ASKUMOUNT		_IOR(AUTOFS_IOCTL, \
229 					     AUTOFS_IOC_ASKUMOUNT_CMD, int)
230 
231 #endif /* _UAPI_LINUX_AUTO_FS_H */
232