OvmfPkg/Include/IndustryStandard/Xen/io/xs_wire.h

   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
  29 enum 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     XS_INVALID = 0xffff /* Guaranteed to remain an invalid type */
  55 };
  56
  57 #define XS_WRITE_NONE "NONE"
  58 #define XS_WRITE_CREATE "CREATE"
  59 #define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
  60
  61 /* We hand errors as strings, for portability. */
  62 struct xsd_errors
  63 {
  64     INT32 errnum;
  65     const CHAR8 *errstring;
  66 };
  67 #ifdef EINVAL
  68 #define XSD_ERROR(x) { x, #x }
  69 /* LINTED: static unused */
  70 static struct xsd_errors xsd_errors[]
  71 #if defined(__GNUC__)
  72 __attribute__((unused))
  73 #endif
  74     = {
  75     XSD_ERROR(EINVAL),
  76     XSD_ERROR(EACCES),
  77     XSD_ERROR(EEXIST),
  78     XSD_ERROR(EISDIR),
  79     XSD_ERROR(ENOENT),
  80     XSD_ERROR(ENOMEM),
  81     XSD_ERROR(ENOSPC),
  82     XSD_ERROR(EIO),
  83     XSD_ERROR(ENOTEMPTY),
  84     XSD_ERROR(ENOSYS),
  85     XSD_ERROR(EROFS),
  86     XSD_ERROR(EBUSY),
  87     XSD_ERROR(EAGAIN),
  88     XSD_ERROR(EISCONN),
  89     XSD_ERROR(E2BIG)
  90 };
  91 #endif
  92
  93 struct xsd_sockmsg
  94 {
  95     UINT32 type;  /* XS_??? */
  96     UINT32 req_id;/* Request identifier, echoed in daemon's response.  */
  97     UINT32 tx_id; /* Transaction id (0 if not related to a transaction). */
  98     UINT32 len;   /* Length of data following this. */
  99
 100     /* Generally followed by nul-terminated string(s). */
 101 };
 102
 103 enum xs_watch_type
 104 {
 105     XS_WATCH_PATH = 0,
 106     XS_WATCH_TOKEN
 107 };
 108
 109 /*
 110  * `incontents 150 xenstore_struct XenStore wire protocol.
 111  *
 112  * Inter-domain shared memory communications. */
 113 #define XENSTORE_RING_SIZE 1024
 114 typedef UINT32 XENSTORE_RING_IDX;
 115 #define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
 116 struct xenstore_domain_interface {
 117     CHAR8 req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
 118     CHAR8 rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
 119     XENSTORE_RING_IDX req_cons, req_prod;
 120     XENSTORE_RING_IDX rsp_cons, rsp_prod;
 121     UINT32 server_features; /* Bitmap of features supported by the server */
 122     UINT32 connection;
 123 };
 124
 125 /* Violating this is very bad.  See docs/misc/xenstore.txt. */
 126 #define XENSTORE_PAYLOAD_MAX 4096
 127
 128 /* Violating these just gets you an error back */
 129 #define XENSTORE_ABS_PATH_MAX 3072
 130 #define XENSTORE_REL_PATH_MAX 2048
 131
 132 /* The ability to reconnect a ring */
 133 #define XENSTORE_SERVER_FEATURE_RECONNECTION 1
 134
 135 /* Valid values for the connection field */
 136 #define XENSTORE_CONNECTED 0 /* the steady-state */
 137 #define XENSTORE_RECONNECT 1 /* guest has initiated a reconnect */
 138
 139 #endif /* _XS_WIRE_H */
 140
 141 /*
 142  * Local variables:
 143  * mode: C
 144  * c-file-style: "BSD"
 145  * c-basic-offset: 4
 146  * tab-width: 4
 147  * indent-tabs-mode: nil
 148  * End:
 149  */