freebsd-nq/sys/cam/ctl/ctl_backend.c
Alexander Motin 34144c2c71 Cleanup LUN addition/removal.
- Make ctl_add_lun() synchronous.  Asynchronous addition was used by
Copan's proprietary code long ago and never for upstream FreeBSD.
 - Move LUN enable/disable calls from backends to CTL core.
 - Serialize LUN modification and partially removal to avoid double frees.
 - Slightly unify backends code.

MFC after:	2 weeks
Sponsored by:	iXsystems, Inc.
2020-05-02 16:54:59 +00:00

143 lines
4.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2003 Silicon Graphics International Corp.
* All rights reserved.
*
* 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,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
*
* $Id: //depot/users/kenm/FreeBSD-test2/sys/cam/ctl/ctl_backend.c#3 $
*/
/*
* CTL backend driver registration routines
*
* Author: Ken Merry <ken@FreeBSD.org>
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/types.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/condvar.h>
#include <sys/queue.h>
#include <sys/sysctl.h>
#include <cam/scsi/scsi_all.h>
#include <cam/scsi/scsi_da.h>
#include <cam/ctl/ctl_io.h>
#include <cam/ctl/ctl.h>
#include <cam/ctl/ctl_frontend.h>
#include <cam/ctl/ctl_backend.h>
#include <cam/ctl/ctl_ioctl.h>
#include <cam/ctl/ctl_ha.h>
#include <cam/ctl/ctl_private.h>
#include <cam/ctl/ctl_debug.h>
extern struct ctl_softc *control_softc;
int
ctl_backend_register(struct ctl_backend_driver *be)
{
struct ctl_softc *softc = control_softc;
struct ctl_backend_driver *be_tmp;
int error;
/* Sanity check, make sure this isn't a duplicate registration. */
mtx_lock(&softc->ctl_lock);
STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
if (strcmp(be_tmp->name, be->name) == 0) {
mtx_unlock(&softc->ctl_lock);
return (-1);
}
}
mtx_unlock(&softc->ctl_lock);
#ifdef CS_BE_CONFIG_MOVE_DONE_IS_NOT_USED
be->config_move_done = ctl_config_move_done;
#endif
/* Call the backend's initialization routine. */
if (be->init != NULL) {
if ((error = be->init()) != 0) {
printf("%s backend init error: %d\n",
be->name, error);
return (error);
}
}
mtx_lock(&softc->ctl_lock);
STAILQ_INSERT_TAIL(&softc->be_list, be, links);
softc->num_backends++;
mtx_unlock(&softc->ctl_lock);
return (0);
}
int
ctl_backend_deregister(struct ctl_backend_driver *be)
{
struct ctl_softc *softc = control_softc;
int error;
/* Call the backend's shutdown routine. */
if (be->shutdown != NULL) {
if ((error = be->shutdown()) != 0) {
printf("%s backend shutdown error: %d\n",
be->name, error);
return (error);
}
}
mtx_lock(&softc->ctl_lock);
STAILQ_REMOVE(&softc->be_list, be, ctl_backend_driver, links);
softc->num_backends--;
mtx_unlock(&softc->ctl_lock);
return (0);
}
struct ctl_backend_driver *
ctl_backend_find(char *backend_name)
{
struct ctl_softc *softc = control_softc;
struct ctl_backend_driver *be_tmp;
mtx_lock(&softc->ctl_lock);
STAILQ_FOREACH(be_tmp, &softc->be_list, links) {
if (strcmp(be_tmp->name, backend_name) == 0) {
mtx_unlock(&softc->ctl_lock);
return (be_tmp);
}
}
mtx_unlock(&softc->ctl_lock);
return (NULL);
}