1/******************************************************************************
2 * Xen Hypervisor Filesystem
3 *
4 * Copyright (c) 2019, SUSE Software Solutions Germany GmbH
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 *
24 */
25
26#ifndef __XEN_PUBLIC_HYPFS_H__
27#define __XEN_PUBLIC_HYPFS_H__
28
29#include "xen.h"
30
31/*
32 * Definitions for the __HYPERVISOR_hypfs_op hypercall.
33 */
34
35/* Highest version number of the hypfs interface currently defined. */
36#define XEN_HYPFS_VERSION      1
37
38/* Maximum length of a path in the filesystem. */
39#define XEN_HYPFS_MAX_PATHLEN  1024
40
41struct xen_hypfs_direntry {
42    uint8_t type;
43#define XEN_HYPFS_TYPE_DIR     0
44#define XEN_HYPFS_TYPE_BLOB    1
45#define XEN_HYPFS_TYPE_STRING  2
46#define XEN_HYPFS_TYPE_UINT    3
47#define XEN_HYPFS_TYPE_INT     4
48#define XEN_HYPFS_TYPE_BOOL    5
49    uint8_t encoding;
50#define XEN_HYPFS_ENC_PLAIN    0
51#define XEN_HYPFS_ENC_GZIP     1
52    uint16_t pad;              /* Returned as 0. */
53    uint32_t content_len;      /* Current length of data. */
54    uint32_t max_write_len;    /* Max. length for writes (0 if read-only). */
55};
56typedef struct xen_hypfs_direntry xen_hypfs_direntry_t;
57
58struct xen_hypfs_dirlistentry {
59    xen_hypfs_direntry_t e;
60    /* Offset in bytes to next entry (0 == this is the last entry). */
61    uint16_t off_next;
62    /* Zero terminated entry name, possibly with some padding for alignment. */
63    char name[XEN_FLEX_ARRAY_DIM];
64};
65
66/*
67 * Hypercall operations.
68 */
69
70/*
71 * XEN_HYPFS_OP_get_version
72 *
73 * Read highest interface version supported by the hypervisor.
74 *
75 * arg1 - arg4: all 0/NULL
76 *
77 * Possible return values:
78 * >0: highest supported interface version
79 * <0: negative Xen errno value
80 */
81#define XEN_HYPFS_OP_get_version     0
82
83/*
84 * XEN_HYPFS_OP_read
85 *
86 * Read a filesystem entry.
87 *
88 * Returns the direntry and contents of an entry in the buffer supplied by the
89 * caller (struct xen_hypfs_direntry with the contents following directly
90 * after it).
91 * The data buffer must be at least the size of the direntry returned. If the
92 * data buffer was not large enough for all the data -ENOBUFS and no entry
93 * data is returned, but the direntry will contain the needed size for the
94 * returned data.
95 * The format of the contents is according to its entry type and encoding.
96 * The contents of a directory are multiple struct xen_hypfs_dirlistentry
97 * items.
98 *
99 * arg1: XEN_GUEST_HANDLE(path name)
100 * arg2: length of path name (including trailing zero byte)
101 * arg3: XEN_GUEST_HANDLE(data buffer written by hypervisor)
102 * arg4: data buffer size
103 *
104 * Possible return values:
105 * 0: success
106 * <0 : negative Xen errno value
107 */
108#define XEN_HYPFS_OP_read              1
109
110/*
111 * XEN_HYPFS_OP_write_contents
112 *
113 * Write contents of a filesystem entry.
114 *
115 * Writes an entry with the contents of a buffer supplied by the caller.
116 * The data type and encoding can't be changed. The size can be changed only
117 * for blobs and strings.
118 *
119 * arg1: XEN_GUEST_HANDLE(path name)
120 * arg2: length of path name (including trailing zero byte)
121 * arg3: XEN_GUEST_HANDLE(content buffer read by hypervisor)
122 * arg4: content buffer size
123 *
124 * Possible return values:
125 * 0: success
126 * <0 : negative Xen errno value
127 */
128#define XEN_HYPFS_OP_write_contents    2
129
130#endif /* __XEN_PUBLIC_HYPFS_H__ */
131