include/linux/blk-iopoll.h

   1 #ifndef BLK_IOPOLL_H
   2 #define BLK_IOPOLL_H
   3
   4 struct blk_iopoll;
   5 typedef int (blk_iopoll_fn)(struct blk_iopoll *, int);
   6
   7 struct blk_iopoll {
   8         struct list_head list;
   9         unsigned long state;
  10         unsigned long data;
  11         int weight;
  12         int max;
  13         blk_iopoll_fn *poll;
  14 };
  15
  16 enum {
  17         IOPOLL_F_SCHED          = 0,
  18         IOPOLL_F_DISABLE        = 1,
  19 };
  20
  21 /*
  22  * Returns 0 if we successfully set the IOPOLL_F_SCHED bit, indicating
  23  * that we were the first to acquire this iop for scheduling. If this iop
  24  * is currently disabled, return "failure".
  25  */
  26 static inline int blk_iopoll_sched_prep(struct blk_iopoll *iop)
  27 {
  28         if (!test_bit(IOPOLL_F_DISABLE, &iop->state))
  29                 return test_and_set_bit(IOPOLL_F_SCHED, &iop->state);
  30
  31         return 1;
  32 }
  33
  34 static inline int blk_iopoll_disable_pending(struct blk_iopoll *iop)
  35 {
  36         return test_bit(IOPOLL_F_DISABLE, &iop->state);
  37 }
  38
  39 extern void blk_iopoll_sched(struct blk_iopoll *);
  40 extern void blk_iopoll_init(struct blk_iopoll *, int, blk_iopoll_fn *);
  41 extern void blk_iopoll_complete(struct blk_iopoll *);
  42 extern void __blk_iopoll_complete(struct blk_iopoll *);
  43 extern void blk_iopoll_enable(struct blk_iopoll *);
  44 extern void blk_iopoll_disable(struct blk_iopoll *);
  45
  46 extern int blk_iopoll_enabled;
  47
  48 #endif