#ifndef BLK_IOPOLL_H
#define BLK_IOPOLL_H

struct blk_iopoll;
typedef int (blk_iopoll_fn)(struct blk_iopoll *, int);

struct blk_iopoll {
struct list_head list;
unsigned long state;
unsigned long data;
int weight;
int max;
blk_iopoll_fn *poll;
};

enum {
IOPOLL_F_SCHED = 0,
IOPOLL_F_DISABLE = 1,
};

/*
* Returns 0 if we successfully set the IOPOLL_F_SCHED bit, indicating
* that we were the first to acquire this iop for scheduling. If this iop
* is currently disabled, return "failure".
*/
static inline int blk_iopoll_sched_prep(struct blk_iopoll *iop)
{
if (!test_bit(IOPOLL_F_DISABLE, &iop->state))
return test_and_set_bit(IOPOLL_F_SCHED, &iop->state);

return 1;
}

static inline int blk_iopoll_disable_pending(struct blk_iopoll *iop)
{
return test_bit(IOPOLL_F_DISABLE, &iop->state);
}

extern void blk_iopoll_sched(struct blk_iopoll *);
extern void blk_iopoll_init(struct blk_iopoll *, int, blk_iopoll_fn *);
extern void blk_iopoll_complete(struct blk_iopoll *);
extern void __blk_iopoll_complete(struct blk_iopoll *);
extern void blk_iopoll_enable(struct blk_iopoll *);
extern void blk_iopoll_disable(struct blk_iopoll *);

extern int blk_iopoll_enabled;

#endif