LXR linux/include/xen/interface/io/xs

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Details of the "wire" protocol between Xen Store Daemon and client
   4 * library or guest kernel.
   5 * Copyright (C) 2005 Rusty Russell IBM Corporation
   6 */
   7
   8#ifndef _XS_WIRE_H
   9#define _XS_WIRE_H
  10
  11enum xsd_sockmsg_type
  12{
  13    XS_DEBUG,
  14    XS_DIRECTORY,
  15    XS_READ,
  16    XS_GET_PERMS,
  17    XS_WATCH,
  18    XS_UNWATCH,
  19    XS_TRANSACTION_START,
  20    XS_TRANSACTION_END,
  21    XS_INTRODUCE,
  22    XS_RELEASE,
  23    XS_GET_DOMAIN_PATH,
  24    XS_WRITE,
  25    XS_MKDIR,
  26    XS_RM,
  27    XS_SET_PERMS,
  28    XS_WATCH_EVENT,
  29    XS_ERROR,
  30    XS_IS_DOMAIN_INTRODUCED,
  31    XS_RESUME,
  32    XS_SET_TARGET,
  33    XS_RESTRICT,
  34    XS_RESET_WATCHES,
  35};
  36
  37#define XS_WRITE_NONE "NONE"
  38#define XS_WRITE_CREATE "CREATE"
  39#define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
  40
  41/* We hand errors as strings, for portability. */
  42struct xsd_errors
  43{
  44    int errnum;
  45    const char *errstring;
  46};
  47#define XSD_ERROR(x) { x, #x }
  48static struct xsd_errors xsd_errors[] __attribute__((unused)) = {
  49    XSD_ERROR(EINVAL),
  50    XSD_ERROR(EACCES),
  51    XSD_ERROR(EEXIST),
  52    XSD_ERROR(EISDIR),
  53    XSD_ERROR(ENOENT),
  54    XSD_ERROR(ENOMEM),
  55    XSD_ERROR(ENOSPC),
  56    XSD_ERROR(EIO),
  57    XSD_ERROR(ENOTEMPTY),
  58    XSD_ERROR(ENOSYS),
  59    XSD_ERROR(EROFS),
  60    XSD_ERROR(EBUSY),
  61    XSD_ERROR(EAGAIN),
  62    XSD_ERROR(EISCONN)
  63};
  64
  65struct xsd_sockmsg
  66{
  67    uint32_t type;  /* XS_??? */
  68    uint32_t req_id;/* Request identifier, echoed in daemon's response.  */
  69    uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */
  70    uint32_t len;   /* Length of data following this. */
  71
  72    /* Generally followed by nul-terminated string(s). */
  73};
  74
  75enum xs_watch_type
  76{
  77    XS_WATCH_PATH = 0,
  78    XS_WATCH_TOKEN
  79};
  80
  81/* Inter-domain shared memory communications. */
  82#define XENSTORE_RING_SIZE 1024
  83typedef uint32_t XENSTORE_RING_IDX;
  84#define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
  85struct xenstore_domain_interface {
  86    char req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
  87    char rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
  88    XENSTORE_RING_IDX req_cons, req_prod;
  89    XENSTORE_RING_IDX rsp_cons, rsp_prod;
  90};
  91
  92/* Violating this is very bad.  See docs/misc/xenstore.txt. */
  93#define XENSTORE_PAYLOAD_MAX 4096
  94
  95#endif /* _XS_WIRE_H */
  96