sys/arch/xen/include/xen3-public/io/xs_wire.h

   1 /* $NetBSD: xs_wire.h,v 1.8 2008/05/04 19:56:29 cegger Exp $ */
   2 /*
   3  * Details of the "wire" protocol between Xen Store Daemon and client
   4  * library or guest kernel.
   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  * Copyright (C) 2005 Rusty Russell IBM Corporation
  25  */
  26
  27 #ifndef _XS_WIRE_H
  28 #define _XS_WIRE_H
  29
  30 enum xsd_sockmsg_type
  31 {
  32     XS_DEBUG,
  33     XS_DIRECTORY,
  34     XS_READ,
  35     XS_GET_PERMS,
  36     XS_WATCH,
  37     XS_UNWATCH,
  38     XS_TRANSACTION_START,
  39     XS_TRANSACTION_END,
  40     XS_INTRODUCE,
  41     XS_RELEASE,
  42     XS_GET_DOMAIN_PATH,
  43     XS_WRITE,
  44     XS_MKDIR,
  45     XS_RM,
  46     XS_SET_PERMS,
  47     XS_WATCH_EVENT,
  48     XS_ERROR,
  49     XS_IS_DOMAIN_INTRODUCED,
  50     XS_RESUME,
  51     XS_SET_TARGET
  52 };
  53
  54 #define XS_WRITE_NONE "NONE"
  55 #define XS_WRITE_CREATE "CREATE"
  56 #define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
  57
  58 /* We hand errors as strings, for portability. */
  59 struct xsd_errors
  60 {
  61     int errnum;
  62     const char *errstring;
  63 };
  64 #define XSD_ERROR(x) { x, #x }
  65 /* LINTED: static unused */
  66 static struct xsd_errors xsd_errors[]
  67 #if defined(__GNUC__)
  68 __attribute__((unused))
  69 #endif
  70     = {
  71     XSD_ERROR(EINVAL),
  72     XSD_ERROR(EACCES),
  73     XSD_ERROR(EEXIST),
  74     XSD_ERROR(EISDIR),
  75     XSD_ERROR(ENOENT),
  76     XSD_ERROR(ENOMEM),
  77     XSD_ERROR(ENOSPC),
  78     XSD_ERROR(EIO),
  79     XSD_ERROR(ENOTEMPTY),
  80     XSD_ERROR(ENOSYS),
  81     XSD_ERROR(EROFS),
  82     XSD_ERROR(EBUSY),
  83     XSD_ERROR(EAGAIN),
  84     XSD_ERROR(EISCONN)
  85 };
  86
  87 struct xsd_sockmsg
  88 {
  89     uint32_t type;  /* XS_??? */
  90     uint32_t req_id;/* Request identifier, echoed in daemon's response.  */
  91     uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */
  92     uint32_t len;   /* Length of data following this. */
  93
  94     /* Generally followed by nul-terminated string(s). */
  95 };
  96
  97 enum xs_watch_type
  98 {
  99     XS_WATCH_PATH = 0,
 100     XS_WATCH_TOKEN
 101 };
 102
 103 /* Inter-domain shared memory communications. */
 104 #define XENSTORE_RING_SIZE 1024
 105 typedef uint32_t XENSTORE_RING_IDX;
 106 #define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
 107 struct xenstore_domain_interface {
 108     char req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
 109     char rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
 110     volatile XENSTORE_RING_IDX req_cons, req_prod;
 111     volatile XENSTORE_RING_IDX rsp_cons, rsp_prod;
 112 };
 113
 114 /* Violating this is very bad.  See docs/misc/xenstore.txt. */
 115 #define XENSTORE_PAYLOAD_MAX 4096
 116
 117 /* Violating these just gets you an error back */
 118 #define XENSTORE_ABS_PATH_MAX 3072
 119 #define XENSTORE_REL_PATH_MAX 2048
 120
 121 #endif /* _XS_WIRE_H */
 122
 123 /*
 124  * Local variables:
 125  * mode: C
 126  * c-set-style: "BSD"
 127  * c-basic-offset: 4
 128  * tab-width: 4
 129  * indent-tabs-mode: nil
 130  * End:
 131  */