1/*
2 * Details of the "wire" protocol between Xen Store Daemon and client
3 * library or guest kernel.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a copy
6 * of this software and associated documentation files (the "Software"), to
7 * deal in the Software without restriction, including without limitation the
8 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
9 * sell copies of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Copyright (C) 2005 Rusty Russell IBM Corporation
24 */
25
26#ifndef _XS_WIRE_H
27#define _XS_WIRE_H
28
29enum xsd_sockmsg_type
30{
31    XS_DEBUG,
32    XS_DIRECTORY,
33    XS_READ,
34    XS_GET_PERMS,
35    XS_WATCH,
36    XS_UNWATCH,
37    XS_TRANSACTION_START,
38    XS_TRANSACTION_END,
39    XS_INTRODUCE,
40    XS_RELEASE,
41    XS_GET_DOMAIN_PATH,
42    XS_WRITE,
43    XS_MKDIR,
44    XS_RM,
45    XS_SET_PERMS,
46    XS_WATCH_EVENT,
47    XS_ERROR,
48    XS_IS_DOMAIN_INTRODUCED,
49    XS_RESUME,
50    XS_SET_TARGET,
51    XS_RESTRICT,
52    XS_RESET_WATCHES
53};
54
55#define XS_WRITE_NONE "NONE"
56#define XS_WRITE_CREATE "CREATE"
57#define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
58
59/* We hand errors as strings, for portability. */
60struct xsd_errors
61{
62    int errnum;
63    const char *errstring;
64};
65#ifdef EINVAL
66#define XSD_ERROR(x) { x, #x }
67/* LINTED: static unused */
68static struct xsd_errors xsd_errors[]
69#if defined(__GNUC__)
70__attribute__((unused))
71#endif
72    = {
73    XSD_ERROR(EINVAL),
74    XSD_ERROR(EACCES),
75    XSD_ERROR(EEXIST),
76    XSD_ERROR(EISDIR),
77    XSD_ERROR(ENOENT),
78    XSD_ERROR(ENOMEM),
79    XSD_ERROR(ENOSPC),
80    XSD_ERROR(EIO),
81    XSD_ERROR(ENOTEMPTY),
82    XSD_ERROR(ENOSYS),
83    XSD_ERROR(EROFS),
84    XSD_ERROR(EBUSY),
85    XSD_ERROR(EAGAIN),
86    XSD_ERROR(EISCONN)
87};
88#endif
89
90struct xsd_sockmsg
91{
92    uint32_t type;  /* XS_??? */
93    uint32_t req_id;/* Request identifier, echoed in daemon's response.  */
94    uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */
95    uint32_t len;   /* Length of data following this. */
96
97    /* Generally followed by nul-terminated string(s). */
98};
99
100enum xs_watch_type
101{
102    XS_WATCH_PATH = 0,
103    XS_WATCH_TOKEN
104};
105
106/* Inter-domain shared memory communications. */
107#define XENSTORE_RING_SIZE 1024
108typedef uint32_t XENSTORE_RING_IDX;
109#define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
110struct xenstore_domain_interface {
111    char req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
112    char rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
113    XENSTORE_RING_IDX req_cons, req_prod;
114    XENSTORE_RING_IDX rsp_cons, rsp_prod;
115};
116
117/* Violating this is very bad.  See docs/misc/xenstore.txt. */
118#define XENSTORE_PAYLOAD_MAX 4096
119
120/* Violating these just gets you an error back */
121#define XENSTORE_ABS_PATH_MAX 3072
122#define XENSTORE_REL_PATH_MAX 2048
123
124#endif /* _XS_WIRE_H */
125
126/*
127 * Local variables:
128 * mode: C
129 * c-set-style: "BSD"
130 * c-basic-offset: 4
131 * tab-width: 4
132 * indent-tabs-mode: nil
133 * End:
134 */
135