NetBSD/sys/dev/dm/dm_target_mirror.c

185 lines
4.8 KiB
C

/*$NetBSD: dm_target_mirror.c,v 1.10 2018/01/05 14:22:26 christos Exp $*/
/*
* Copyright (c) 2009 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Adam Hamsik.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: dm_target_mirror.c,v 1.10 2018/01/05 14:22:26 christos Exp $");
/*
* This file implements initial version of device-mapper mirror target.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/buf.h>
#include "dm.h"
/* dm_target_mirror.c */
int dm_target_mirror_init(dm_dev_t *, void**, char *);
char * dm_target_mirror_status(void *);
int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *);
int dm_target_mirror_sync(dm_table_entry_t *);
int dm_target_mirror_deps(dm_table_entry_t *, prop_array_t);
int dm_target_mirror_destroy(dm_table_entry_t *);
int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *);
#ifdef DM_TARGET_MODULE
/*
* Every target can be compiled directly to dm driver or as a
* separate module this part of target is used for loading targets
* to dm driver.
* Target can be unloaded from kernel only if there are no users of
* it e.g. there are no devices which uses that target.
*/
#include <sys/kernel.h>
#include <sys/module.h>
MODULE(MODULE_CLASS_MISC, dm_target_mirror, "dm");
static int
dm_target_mirror_modcmd(modcmd_t cmd, void *arg)
{
dm_target_t *dmt;
int r;
dmt = NULL;
switch (cmd) {
case MODULE_CMD_INIT:
if ((dmt = dm_target_lookup("mirror")) != NULL) {
dm_target_unbusy(dmt);
return EEXIST;
}
dmt = dm_target_alloc("mirror");
dmt->version[0] = 1;
dmt->version[1] = 0;
dmt->version[2] = 0;
strlcpy(dmt->name, "mirror", DM_MAX_TYPE_NAME);
dmt->init = &dm_target_mirror_init;
dmt->status = &dm_target_mirror_status;
dmt->strategy = &dm_target_mirror_strategy;
dmt->sync = &dm_target_mirror_sync;
dmt->deps = &dm_target_mirror_deps;
dmt->destroy = &dm_target_mirror_destroy;
dmt->upcall = &dm_target_mirror_upcall;
r = dm_target_insert(dmt);
break;
case MODULE_CMD_FINI:
r = dm_target_rem("mirror");
break;
case MODULE_CMD_STAT:
return ENOTTY;
default:
return ENOTTY;
}
return r;
}
#endif
/*
* Init function called from dm_table_load_ioctl.
* start length mirror log_type #logargs logarg1 ... logargN #devs device1 offset1 ... deviceN offsetN
* 0 52428800 mirror clustered_disk 4 253:2 1024 UUID block_on_error 3 253:3 0 253:4 0 253:5 0
*/
int
dm_target_mirror_init(dm_dev_t * dmv, void **target_config, char *argv)
{
printf("Mirror target init function called!!\n");
*target_config = NULL;
dmv->dev_type = DM_MIRROR_DEV;
return ENOSYS;
}
/* Status routine called to get params string. */
char *
dm_target_mirror_status(void *target_config)
{
return NULL;
}
/* Strategy routine called from dm_strategy. */
int
dm_target_mirror_strategy(dm_table_entry_t * table_en, struct buf * bp)
{
printf("Mirror target read function called!!\n");
bp->b_error = EIO;
bp->b_resid = 0;
biodone(bp);
return 0;
}
/* Sync underlying disk caches. */
int
dm_target_mirror_sync(dm_table_entry_t * table_en)
{
return 0;
}
/* Doesn't do anything here. */
int
dm_target_mirror_destroy(dm_table_entry_t * table_en)
{
table_en->target_config = NULL;
/* Unbusy target so we can unload it */
dm_target_unbusy(table_en->target);
return 0;
}
/* Doesn't not need to do anything here. */
int
dm_target_mirror_deps(dm_table_entry_t * table_en, prop_array_t prop_array)
{
return 0;
}
/* Unsupported for this target. */
int
dm_target_mirror_upcall(dm_table_entry_t * table_en, struct buf * bp)
{
return 0;
}