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/* SPDX-License-Identifier: MIT */
/*
* Details of the "wire" protocol between Xen Store Daemon and client
* library or guest kernel.
* Copyright (C) 2005 Rusty Russell IBM Corporation
*/
#ifndef _XS_WIRE_H
#define _XS_WIRE_H
enum xsd_sockmsg_type
{
XS_CONTROL,
#define XS_DEBUG XS_CONTROL
XS_DIRECTORY,
XS_READ,
XS_GET_PERMS,
XS_WATCH,
XS_UNWATCH,
XS_TRANSACTION_START,
XS_TRANSACTION_END,
XS_INTRODUCE,
XS_RELEASE,
XS_GET_DOMAIN_PATH,
XS_WRITE,
XS_MKDIR,
XS_RM,
XS_SET_PERMS,
XS_WATCH_EVENT,
XS_ERROR,
XS_IS_DOMAIN_INTRODUCED,
XS_RESUME,
XS_SET_TARGET,
/* XS_RESTRICT has been removed */
XS_RESET_WATCHES = XS_SET_TARGET + 2,
XS_DIRECTORY_PART,
XS_TYPE_COUNT, /* Number of valid types. */
XS_INVALID = 0xffff /* Guaranteed to remain an invalid type */
};
#define XS_WRITE_NONE "NONE"
#define XS_WRITE_CREATE "CREATE"
#define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
/* We hand errors as strings, for portability. */
struct xsd_errors
{
int errnum;
const char *errstring;
};
#define XSD_ERROR(x) { x, #x }
static struct xsd_errors xsd_errors[] __attribute__((unused)) = {
XSD_ERROR(EINVAL),
XSD_ERROR(EACCES),
XSD_ERROR(EEXIST),
XSD_ERROR(EISDIR),
XSD_ERROR(ENOENT),
XSD_ERROR(ENOMEM),
XSD_ERROR(ENOSPC),
XSD_ERROR(EIO),
XSD_ERROR(ENOTEMPTY),
XSD_ERROR(ENOSYS),
XSD_ERROR(EROFS),
XSD_ERROR(EBUSY),
XSD_ERROR(EAGAIN),
XSD_ERROR(EISCONN),
XSD_ERROR(E2BIG)
};
struct xsd_sockmsg
{
uint32_t type; /* XS_??? */
uint32_t req_id;/* Request identifier, echoed in daemon's response. */
uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */
uint32_t len; /* Length of data following this. */
/* Generally followed by nul-terminated string(s). */
};
enum xs_watch_type
{
XS_WATCH_PATH = 0,
XS_WATCH_TOKEN
};
/* Inter-domain shared memory communications. */
#define XENSTORE_RING_SIZE 1024
typedef uint32_t XENSTORE_RING_IDX;
#define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
struct xenstore_domain_interface {
char req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
char rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
XENSTORE_RING_IDX req_cons, req_prod;
XENSTORE_RING_IDX rsp_cons, rsp_prod;
uint32_t server_features; /* Bitmap of features supported by the server */
uint32_t connection;
uint32_t error;
};
/* Violating this is very bad. See docs/misc/xenstore.txt. */
#define XENSTORE_PAYLOAD_MAX 4096
/* Violating these just gets you an error back */
#define XENSTORE_ABS_PATH_MAX 3072
#define XENSTORE_REL_PATH_MAX 2048
/* The ability to reconnect a ring */
#define XENSTORE_SERVER_FEATURE_RECONNECTION 1
/* The presence of the "error" field in the ring page */
#define XENSTORE_SERVER_FEATURE_ERROR 2
/* Valid values for the connection field */
#define XENSTORE_CONNECTED 0 /* the steady-state */
#define XENSTORE_RECONNECT 1 /* guest has initiated a reconnect */
/* Valid values for the error field */
#define XENSTORE_ERROR_NONE 0 /* No error */
#define XENSTORE_ERROR_COMM 1 /* Communication problem */
#define XENSTORE_ERROR_RINGIDX 2 /* Invalid ring index */
#define XENSTORE_ERROR_PROTO 3 /* Protocol violation (payload too long) */
#endif /* _XS_WIRE_H */