docker: Add EXTRA_CONFIGURE_OPTS
[qemu.git] / linux-headers / linux / userfaultfd.h
1 /*
2 * include/linux/userfaultfd.h
3 *
4 * Copyright (C) 2007 Davide Libenzi <davidel@xmailserver.org>
5 * Copyright (C) 2015 Red Hat, Inc.
6 *
7 */
8
9 #ifndef _LINUX_USERFAULTFD_H
10 #define _LINUX_USERFAULTFD_H
11
12 #include <linux/types.h>
13
14 #define UFFD_API ((__u64)0xAA)
15 /*
16 * After implementing the respective features it will become:
17 * #define UFFD_API_FEATURES (UFFD_FEATURE_PAGEFAULT_FLAG_WP | \
18 * UFFD_FEATURE_EVENT_FORK)
19 */
20 #define UFFD_API_FEATURES (0)
21 #define UFFD_API_IOCTLS \
22 ((__u64)1 << _UFFDIO_REGISTER | \
23 (__u64)1 << _UFFDIO_UNREGISTER | \
24 (__u64)1 << _UFFDIO_API)
25 #define UFFD_API_RANGE_IOCTLS \
26 ((__u64)1 << _UFFDIO_WAKE | \
27 (__u64)1 << _UFFDIO_COPY | \
28 (__u64)1 << _UFFDIO_ZEROPAGE)
29
30 /*
31 * Valid ioctl command number range with this API is from 0x00 to
32 * 0x3F. UFFDIO_API is the fixed number, everything else can be
33 * changed by implementing a different UFFD_API. If sticking to the
34 * same UFFD_API more ioctl can be added and userland will be aware of
35 * which ioctl the running kernel implements through the ioctl command
36 * bitmask written by the UFFDIO_API.
37 */
38 #define _UFFDIO_REGISTER (0x00)
39 #define _UFFDIO_UNREGISTER (0x01)
40 #define _UFFDIO_WAKE (0x02)
41 #define _UFFDIO_COPY (0x03)
42 #define _UFFDIO_ZEROPAGE (0x04)
43 #define _UFFDIO_API (0x3F)
44
45 /* userfaultfd ioctl ids */
46 #define UFFDIO 0xAA
47 #define UFFDIO_API _IOWR(UFFDIO, _UFFDIO_API, \
48 struct uffdio_api)
49 #define UFFDIO_REGISTER _IOWR(UFFDIO, _UFFDIO_REGISTER, \
50 struct uffdio_register)
51 #define UFFDIO_UNREGISTER _IOR(UFFDIO, _UFFDIO_UNREGISTER, \
52 struct uffdio_range)
53 #define UFFDIO_WAKE _IOR(UFFDIO, _UFFDIO_WAKE, \
54 struct uffdio_range)
55 #define UFFDIO_COPY _IOWR(UFFDIO, _UFFDIO_COPY, \
56 struct uffdio_copy)
57 #define UFFDIO_ZEROPAGE _IOWR(UFFDIO, _UFFDIO_ZEROPAGE, \
58 struct uffdio_zeropage)
59
60 /* read() structure */
61 struct uffd_msg {
62 __u8 event;
63
64 __u8 reserved1;
65 __u16 reserved2;
66 __u32 reserved3;
67
68 union {
69 struct {
70 __u64 flags;
71 __u64 address;
72 } pagefault;
73
74 struct {
75 /* unused reserved fields */
76 __u64 reserved1;
77 __u64 reserved2;
78 __u64 reserved3;
79 } reserved;
80 } arg;
81 } __attribute__((packed));
82
83 /*
84 * Start at 0x12 and not at 0 to be more strict against bugs.
85 */
86 #define UFFD_EVENT_PAGEFAULT 0x12
87 #if 0 /* not available yet */
88 #define UFFD_EVENT_FORK 0x13
89 #endif
90
91 /* flags for UFFD_EVENT_PAGEFAULT */
92 #define UFFD_PAGEFAULT_FLAG_WRITE (1<<0) /* If this was a write fault */
93 #define UFFD_PAGEFAULT_FLAG_WP (1<<1) /* If reason is VM_UFFD_WP */
94
95 struct uffdio_api {
96 /* userland asks for an API number and the features to enable */
97 __u64 api;
98 /*
99 * Kernel answers below with the all available features for
100 * the API, this notifies userland of which events and/or
101 * which flags for each event are enabled in the current
102 * kernel.
103 *
104 * Note: UFFD_EVENT_PAGEFAULT and UFFD_PAGEFAULT_FLAG_WRITE
105 * are to be considered implicitly always enabled in all kernels as
106 * long as the uffdio_api.api requested matches UFFD_API.
107 */
108 #if 0 /* not available yet */
109 #define UFFD_FEATURE_PAGEFAULT_FLAG_WP (1<<0)
110 #define UFFD_FEATURE_EVENT_FORK (1<<1)
111 #endif
112 __u64 features;
113
114 __u64 ioctls;
115 };
116
117 struct uffdio_range {
118 __u64 start;
119 __u64 len;
120 };
121
122 struct uffdio_register {
123 struct uffdio_range range;
124 #define UFFDIO_REGISTER_MODE_MISSING ((__u64)1<<0)
125 #define UFFDIO_REGISTER_MODE_WP ((__u64)1<<1)
126 __u64 mode;
127
128 /*
129 * kernel answers which ioctl commands are available for the
130 * range, keep at the end as the last 8 bytes aren't read.
131 */
132 __u64 ioctls;
133 };
134
135 struct uffdio_copy {
136 __u64 dst;
137 __u64 src;
138 __u64 len;
139 /*
140 * There will be a wrprotection flag later that allows to map
141 * pages wrprotected on the fly. And such a flag will be
142 * available if the wrprotection ioctl are implemented for the
143 * range according to the uffdio_register.ioctls.
144 */
145 #define UFFDIO_COPY_MODE_DONTWAKE ((__u64)1<<0)
146 __u64 mode;
147
148 /*
149 * "copy" is written by the ioctl and must be at the end: the
150 * copy_from_user will not read the last 8 bytes.
151 */
152 __s64 copy;
153 };
154
155 struct uffdio_zeropage {
156 struct uffdio_range range;
157 #define UFFDIO_ZEROPAGE_MODE_DONTWAKE ((__u64)1<<0)
158 __u64 mode;
159
160 /*
161 * "zeropage" is written by the ioctl and must be at the end:
162 * the copy_from_user will not read the last 8 bytes.
163 */
164 __s64 zeropage;
165 };
166
167 #endif /* _LINUX_USERFAULTFD_H */