#ifndef QEMU_HW_XEN_BACKEND_H
#define QEMU_HW_XEN_BACKEND_H 1

#include "xen_common.h"

/* ------------------------------------------------------------- */

#define XEN_BUFSIZE 1024

struct XenDevice;

/* driver uses grant tables  ->  open gntdev device (xendev->gnttabdev) */
#define DEVOPS_FLAG_NEED_GNTDEV   1
/* don't expect frontend doing correct state transitions (aka console quirk) */
#define DEVOPS_FLAG_IGNORE_STATE  2

struct XenDevOps {
    size_t    size;
    uint32_t  flags;
    void      (*alloc)(struct XenDevice *xendev);
    int       (*init)(struct XenDevice *xendev);
    int       (*connect)(struct XenDevice *xendev);
    void      (*event)(struct XenDevice *xendev);
    void      (*disconnect)(struct XenDevice *xendev);
    int       (*free)(struct XenDevice *xendev);
    void      (*backend_changed)(struct XenDevice *xendev, const char *node);
    void      (*frontend_changed)(struct XenDevice *xendev, const char *node);
};

struct XenDevice {
    const char         *type;
    int                dom;
    int                dev;
    char               name[64];
    int                debug;

    enum xenbus_state  be_state;
    enum xenbus_state  fe_state;
    int                online;
    char               be[XEN_BUFSIZE];
    char               *fe;
    char               *protocol;
    int                remote_port;
    int                local_port;

    int                evtchndev;
    int                gnttabdev;

    struct XenDevOps   *ops;
    TAILQ_ENTRY(XenDevice) next;
};

/* ------------------------------------------------------------- */

/* variables */
extern int xen_xc;
extern struct xs_handle *xenstore;

/* xenstore helper functions */
int xenstore_write_str(const char *base, const char *node, const char *val);
int xenstore_write_int(const char *base, const char *node, int ival);
char *xenstore_read_str(const char *base, const char *node);
int xenstore_read_int(const char *base, const char *node, int *ival);

int xenstore_write_be_str(struct XenDevice *xendev, const char *node, const char *val);
int xenstore_write_be_int(struct XenDevice *xendev, const char *node, int ival);
char *xenstore_read_be_str(struct XenDevice *xendev, const char *node);
int xenstore_read_be_int(struct XenDevice *xendev, const char *node, int *ival);
char *xenstore_read_fe_str(struct XenDevice *xendev, const char *node);
int xenstore_read_fe_int(struct XenDevice *xendev, const char *node, int *ival);

const char *xenbus_strstate(enum xenbus_state state);
struct XenDevice *xen_be_find_xendev(const char *type, int dom, int dev);
void xen_be_check_state(struct XenDevice *xendev);

/* xen backend driver bits */
int xen_be_init(void);
int xen_be_register(const char *type, struct XenDevOps *ops);
int xen_be_set_state(struct XenDevice *xendev, enum xenbus_state state);
int xen_be_bind_evtchn(struct XenDevice *xendev);
void xen_be_unbind_evtchn(struct XenDevice *xendev);
int xen_be_send_notify(struct XenDevice *xendev);
void xen_be_printf(struct XenDevice *xendev, int msg_level, const char *fmt, ...)
    __attribute__ ((format(printf, 3, 4)));

/* actual backend drivers */
extern struct XenDevOps xen_console_ops;      /* xen_console.c     */

#endif /* QEMU_HW_XEN_BACKEND_H */