io_u_queue.c

   1 #include <stdlib.h>
   2 #include "io_u_queue.h"
   3
   4 int io_u_qinit(struct io_u_queue *q, unsigned int nr)
   5 {
   6         q->io_us = calloc(nr, sizeof(struct io_u *));
   7         if (!q->io_us)
   8                 return 1;
   9
  10         q->nr = 0;
  11         q->max = nr;
  12         return 0;
  13 }
  14
  15 void io_u_qexit(struct io_u_queue *q)
  16 {
  17         free(q->io_us);
  18 }
  19
  20 int io_u_rinit(struct io_u_ring *ring, unsigned int nr)
  21 {
  22         ring->max = nr + 1;
  23         if (ring->max & (ring->max - 1)) {
  24                 ring->max--;
  25                 ring->max |= ring->max >> 1;
  26                 ring->max |= ring->max >> 2;
  27                 ring->max |= ring->max >> 4;
  28                 ring->max |= ring->max >> 8;
  29                 ring->max |= ring->max >> 16;
  30                 ring->max++;
  31         }
  32
  33         ring->ring = calloc(ring->max, sizeof(struct io_u *));
  34         if (!ring->ring)
  35                 return 1;
  36
  37         ring->head = ring->tail = 0;
  38         return 0;
  39 }
  40
  41 void io_u_rexit(struct io_u_ring *ring)
  42 {
  43         free(ring->ring);
  44 }