include/xen/interface/io/xs_wire.h

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