mirror_zfs/lib/libspl/include/sys/file.h
George Wilson 2efea7c82c ZFS Reads may result in unneccesary calls to zil_commit
ZFS supports O_RSYNC for read operations and when specified will ensure
the same level of data integrity that O_DSYNC and O_SYNC provides for
writes. O_RSYNC by itself has no effect so it must be combined with
either O_DSYNC or O_SYNC. However, many platforms don't support O_RSYNC
and have mapped O_SYNC to mean O_RSYNC within ZFS. This is incorrect
and causes unnecessary calls to zil_commit. Only platforms which
support O_RSYNC should implement the zil_commit functionality in the
read code path.

Reviewed-by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: George Wilson <george.wilson@delphix.com>
Closes #8523
2019-03-22 13:09:11 -07:00

50 lines
1.4 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _LIBSPL_SYS_FILE_H
#define _LIBSPL_SYS_FILE_H
#include_next <sys/file.h>
#include <sys/user.h>
#define FREAD 1
#define FWRITE 2
// #define FAPPEND 8
#define FCREAT O_CREAT
#define FTRUNC O_TRUNC
#define FOFFMAX O_LARGEFILE
#define FSYNC O_SYNC
#define FDSYNC O_DSYNC
#define FEXCL O_EXCL
#define FNODSYNC 0x10000 /* fsync pseudo flag */
#define FNOFOLLOW 0x20000 /* don't follow symlinks */
#define FIGNORECASE 0x80000 /* request case-insensitive lookups */
#endif