xref: /aosp_15_r20/external/ltp/include/lapi/watch_queue.h (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2021 SUSE LLC Andrea Cervesato <[email protected]>
4  *
5  * This file is created to resolve conflicts between user space and kernel
6  * space fctnl.h declaration. linux/watch_queue.h is not handled, since
7  * user space fcntl.h redefines kernel space structures.
8  */
9 
10 #ifndef LAPI_WATCH_QUEUE_H__
11 #define LAPI_WATCH_QUEUE_H__
12 
13 #include <stdint.h>
14 #include "lapi/ioctl.h"
15 #include "lapi/fcntl.h"
16 
17 #define O_NOTIFICATION_PIPE	O_EXCL	/* Parameter to pipe2() selecting notification pipe */
18 
19 #define IOC_WATCH_QUEUE_SET_SIZE	_IO('W', 0x60)	/* Set the size in pages */
20 #define IOC_WATCH_QUEUE_SET_FILTER	_IO('W', 0x61)	/* Set the filter */
21 
22 enum watch_notification_type {
23 	WATCH_TYPE_META		= 0,	/* Special record */
24 	WATCH_TYPE_KEY_NOTIFY	= 1,	/* Key change event notification */
25 	WATCH_TYPE__NR		= 2
26 };
27 
28 enum watch_meta_notification_subtype {
29 	WATCH_META_REMOVAL_NOTIFICATION	= 0,	/* Watched object was removed */
30 	WATCH_META_LOSS_NOTIFICATION	= 1,	/* Data loss occurred */
31 };
32 
33 /*
34  * Notification record header.  This is aligned to 64-bits so that subclasses
35  * can contain __u64 fields.
36  */
37 struct watch_notification {
38 	uint32_t			type:24;	/* enum watch_notification_type */
39 	uint32_t			subtype:8;	/* Type-specific subtype (filterable) */
40 	uint32_t			info;
41 #define WATCH_INFO_LENGTH	0x0000007f	/* Length of record */
42 #define WATCH_INFO_LENGTH__SHIFT 0
43 #define WATCH_INFO_ID		0x0000ff00	/* ID of watchpoint */
44 #define WATCH_INFO_ID__SHIFT	8
45 #define WATCH_INFO_TYPE_INFO	0xffff0000	/* Type-specific info */
46 #define WATCH_INFO_TYPE_INFO__SHIFT 16
47 #define WATCH_INFO_FLAG_0	0x00010000	/* Type-specific info, flag bit 0 */
48 #define WATCH_INFO_FLAG_1	0x00020000	/* ... */
49 #define WATCH_INFO_FLAG_2	0x00040000
50 #define WATCH_INFO_FLAG_3	0x00080000
51 #define WATCH_INFO_FLAG_4	0x00100000
52 #define WATCH_INFO_FLAG_5	0x00200000
53 #define WATCH_INFO_FLAG_6	0x00400000
54 #define WATCH_INFO_FLAG_7	0x00800000
55 };
56 
57 /*
58  * Notification filtering rules (IOC_WATCH_QUEUE_SET_FILTER).
59  */
60 struct watch_notification_type_filter {
61 	uint32_t	type;			/* Type to apply filter to */
62 	uint32_t	info_filter;		/* Filter on watch_notification::info */
63 	uint32_t	info_mask;		/* Mask of relevant bits in info_filter */
64 	uint32_t	subtype_filter[8];	/* Bitmask of subtypes to filter on */
65 };
66 
67 struct watch_notification_filter {
68 	uint32_t	nr_filters;		/* Number of filters */
69 	uint32_t	__reserved;		/* Must be 0 */
70 	struct watch_notification_type_filter filters[];
71 };
72 
73 
74 /*
75  * Extended watch removal notification.  This is used optionally if the type
76  * wants to indicate an identifier for the object being watched, if there is
77  * such.  This can be distinguished by the length.
78  *
79  * type -> WATCH_TYPE_META
80  * subtype -> WATCH_META_REMOVAL_NOTIFICATION
81  */
82 struct watch_notification_removal {
83 	struct watch_notification watch;
84 	uint64_t	id;		/* Type-dependent identifier */
85 };
86 
87 /*
88  * Type of key/keyring change notification.
89  */
90 enum key_notification_subtype {
91 	NOTIFY_KEY_INSTANTIATED	= 0, /* Key was instantiated (aux is error code) */
92 	NOTIFY_KEY_UPDATED	= 1, /* Key was updated */
93 	NOTIFY_KEY_LINKED	= 2, /* Key (aux) was added to watched keyring */
94 	NOTIFY_KEY_UNLINKED	= 3, /* Key (aux) was removed from watched keyring */
95 	NOTIFY_KEY_CLEARED	= 4, /* Keyring was cleared */
96 	NOTIFY_KEY_REVOKED	= 5, /* Key was revoked */
97 	NOTIFY_KEY_INVALIDATED	= 6, /* Key was invalidated */
98 	NOTIFY_KEY_SETATTR	= 7, /* Key's attributes got changed */
99 };
100 
101 /*
102  * Key/keyring notification record.
103  * - watch.type = WATCH_TYPE_KEY_NOTIFY
104  * - watch.subtype = enum key_notification_type
105  */
106 struct key_notification {
107 	struct watch_notification watch;
108 	uint32_t	key_id;		/* The key/keyring affected */
109 	uint32_t	aux;		/* Per-type auxiliary data */
110 };
111 
112 #endif /* LAPI_WATCH_QUEUE_H__ */
113