auto_fs.h

  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 */
 36typedef unsigned long autofs_wqt_t;
 37#else
 38typedef 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
 45struct autofs_packet_hdr {
 46	int proto_version;		/* Protocol version */
 47	int type;			/* Type of packet */
 48};
 49
 50struct 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) */
 58struct 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
 66enum {
 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
103static inline void set_autofs_type_indirect(unsigned int *type)
104{
105	*type = AUTOFS_TYPE_INDIRECT;
106}
107
108static inline unsigned int autofs_type_indirect(unsigned int type)
109{
110	return (type == AUTOFS_TYPE_INDIRECT);
111}
112
113static inline void set_autofs_type_direct(unsigned int *type)
114{
115	*type = AUTOFS_TYPE_DIRECT;
116}
117
118static inline unsigned int autofs_type_direct(unsigned int type)
119{
120	return (type == AUTOFS_TYPE_DIRECT);
121}
122
123static inline void set_autofs_type_offset(unsigned int *type)
124{
125	*type = AUTOFS_TYPE_OFFSET;
126}
127
128static inline unsigned int autofs_type_offset(unsigned int type)
129{
130	return (type == AUTOFS_TYPE_OFFSET);
131}
132
133static 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 */
143static inline void set_autofs_type_any(unsigned int *type)
144{
145	*type = AUTOFS_TYPE_ANY;
146}
147
148static inline unsigned int autofs_type_any(unsigned int type)
149{
150	return (type == AUTOFS_TYPE_ANY);
151}
152
153/* Daemon notification packet types */
154enum 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) */
176struct 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
183union 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 */
191struct 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
204typedef struct autofs_v5_packet autofs_packet_missing_indirect_t;
205typedef struct autofs_v5_packet autofs_packet_expire_indirect_t;
206typedef struct autofs_v5_packet autofs_packet_missing_direct_t;
207typedef struct autofs_v5_packet autofs_packet_expire_direct_t;
208
209union 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
218enum {
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 */