1 /* 2 * Copyright (c) 2008, XenSource Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * * Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * * Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * * Neither the name of XenSource Inc. nor the names of its contributors 13 * may be used to endorse or promote products derived from this software 14 * without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 20 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 23 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 24 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 25 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 26 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef __IO_OPTIMIZE_H__ 30 #define __IO_OPTIMIZE_H__ 31 32 #include <libaio.h> 33 34 struct opio; 35 36 struct opio_list { 37 struct opio *head; 38 struct opio *tail; 39 }; 40 41 struct opio { 42 char *buf; 43 unsigned long nbytes; 44 long long offset; 45 void *data; 46 struct iocb *iocb; 47 struct io_event event; 48 struct opio *head; 49 struct opio *next; 50 struct opio_list list; 51 }; 52 53 struct opioctx { 54 int num_opios; 55 int free_opio_cnt; 56 struct opio *opios; 57 struct opio **free_opios; 58 struct iocb **iocb_queue; 59 struct io_event *event_queue; 60 }; 61 62 int opio_init(struct opioctx *ctx, int num_iocbs); 63 void opio_free(struct opioctx *ctx); 64 int io_merge(struct opioctx *ctx, struct iocb **queue, int num); 65 int io_split(struct opioctx *ctx, struct io_event *events, int num); 66 int io_expand_iocbs(struct opioctx *ctx, struct iocb **queue, int idx, int num); 67 68 #endif 69