util/aiocb.c

   1 /*
   2  * BlockAIOCB allocation
   3  *
   4  * Copyright (c) 2003-2017 Fabrice Bellard and other QEMU contributors
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25 #include "qemu/osdep.h"
  26 #include "block/aio.h"
  27
  28 void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs,
  29                    BlockCompletionFunc *cb, void *opaque)
  30 {
  31     BlockAIOCB *acb;
  32
  33     acb = g_malloc(aiocb_info->aiocb_size);
  34     acb->aiocb_info = aiocb_info;
  35     acb->bs = bs;
  36     acb->cb = cb;
  37     acb->opaque = opaque;
  38     acb->refcnt = 1;
  39     return acb;
  40 }
  41
  42 void qemu_aio_ref(void *p)
  43 {
  44     BlockAIOCB *acb = p;
  45     acb->refcnt++;
  46 }
  47
  48 void qemu_aio_unref(void *p)
  49 {
  50     BlockAIOCB *acb = p;
  51     assert(acb->refcnt > 0);
  52     if (--acb->refcnt == 0) {
  53         g_free(acb);
  54     }
  55 }