ns/nsctl/nsc_freeze.c

fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * CDDL HEADER START
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * The contents of this file are subject to the terms of the
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Common Development and Distribution License (the "License").
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * You may not use this file except in compliance with the License.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * or http://www.opensolaris.org/os/licensing.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * See the License for the specific language governing permissions
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * and limitations under the License.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * When distributing Covered Code, include this CDDL HEADER in each
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * If applicable, add the following below this CDDL HEADER, with the
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * fields enclosed by brackets "[]" replaced with your own identifying
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * information: Portions Copyright [yyyy] [name of copyright owner]
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * CDDL HEADER END
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Use is subject to license terms.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/types.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/errno.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/cmn_err.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/ksynch.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/kmem.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include <sys/ddi.h>
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#define __NSC_GEN__
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include "nsc_dev.h"
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte#include "../nsctl.h"
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * (Un)Freeze Module
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * This module provides a means to 'freeze' a device and ensure
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * that no SP software has an open reference to that device.  Later
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * the device can be 'unfrozen' and the SP software can resume
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * normal operations.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * This module is required because it is possible to place a virtual
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * volume driver (RAID-0, 1 or 5) into a state whereby it needs to be
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * disabled for corrective action.  The (un)freeze facility provides a
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * method of doing this without downtime.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * A device that is frozen should be frozen on all nodes.  It is the
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * responsibility of the management software or the user to perform
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * the freeze and unfreeze on the required nodes.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteextern nsc_mem_t *_nsc_local_mem;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortetypedef struct _nsc_frz_s {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    struct _nsc_frz_s   *next;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    nsc_path_t      *token;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    char            path[NSC_MAXPATH];
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte} _nsc_frz_t;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteextern int _nsc_frz_stop(char *, int *);        /* forward decl */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic _nsc_frz_t *_nsc_frz_top;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic nsc_def_t _nsc_frz_def[];
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic kmutex_t _nsc_frz_sleep;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic nsc_io_t *_nsc_frz_io;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortevoid
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_init_frz(void)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_init(&_nsc_frz_sleep, NULL, MUTEX_DRIVER, NULL);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    _nsc_frz_io = nsc_register_io("frz",
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            NSC_FREEZE_ID | NSC_FILTER, _nsc_frz_def);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (!_nsc_frz_io)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        cmn_err(CE_WARN, "nsctl: _nsc_init_frz: register failed");
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortevoid
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_deinit_frz(void)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (_nsc_frz_io)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        (void) nsc_unregister_io(_nsc_frz_io, 0);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    _nsc_frz_io = NULL;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_destroy(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * int _nsc_frz_start(char *path, int *rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Freeze a device
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Calling/Exit State:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Must be called from a context that can block.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Returns 0 for success, or one of the following error codes:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *      EINVAL   - invalid 'path' argument
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *      ENOMEM   - failed to allocate memory
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *      EALREADY - 'path' is already frozen
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Description:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Registers 'path' to be accessed through the NSC_FREEZE_ID
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  io module, and forces any open file descriptors for 'path'
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  to be re-opened as appropriate.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_start(path, rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortechar *path;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint *rvp;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    _nsc_frz_t *frz, *xfrz;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    int rc;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    *rvp = 0;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (strlen(path) >= NSC_MAXPATH)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (EINVAL);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    frz = nsc_kmem_zalloc(sizeof (*frz), KM_SLEEP, _nsc_local_mem);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (!frz)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (ENOMEM);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    (void) strcpy(frz->path, path);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_enter(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    for (xfrz = _nsc_frz_top; xfrz; xfrz = xfrz->next)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        if (strcmp(frz->path, xfrz->path) == 0)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            break;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (!xfrz) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        frz->next = _nsc_frz_top;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        _nsc_frz_top = frz;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_exit(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (xfrz) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        nsc_kmem_free(frz, sizeof (*frz));
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (EALREADY);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    frz->token = nsc_register_path(path, NSC_DEVICE, _nsc_frz_io);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (!frz->token) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        (void) _nsc_frz_stop(path, &rc);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (EINVAL);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    return (0);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * int _nsc_frz_stop(char *path, int *rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Unfreeze a device
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Calling/Exit State:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Must be called from a context that can block.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Returns 0 or an error code.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Description:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Removes the path registration for the NSC_FREEZE_ID io module
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  and forces any re-opens as appropriate.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_stop(path, rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortechar *path;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint *rvp;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    _nsc_frz_t **xfrz, *frz = NULL;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    int rc = 0;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    *rvp = 0;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_enter(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    for (xfrz = &_nsc_frz_top; *xfrz; xfrz = &(*xfrz)->next)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        if (strcmp(path, (*xfrz)->path) == 0) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            frz = *xfrz;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            break;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (!frz) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        mutex_exit(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (EINVAL);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (frz->token)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        rc = nsc_unregister_path(frz->token, NSC_PCATCH);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (rc) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        mutex_exit(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (rc);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    (*xfrz) = frz->next;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_exit(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    nsc_kmem_free(frz, sizeof (*frz));
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    return (0);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * int _nsc_frz_isfrozen(char *path, int *rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Tests whether a device is frozen.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Calling/Exit State:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Returns 0 or EINVAL.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Sets *rvp to 1 if the device was not frozen, and 0 otherwise.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  This function returns historical information.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_isfrozen(path, rvp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortechar *path;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint *rvp;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    _nsc_frz_t *frz;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    *rvp = 1;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    if (! _nsc_frz_io)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        return (EINVAL);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_enter(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    for (frz = _nsc_frz_top; frz; frz = frz->next)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        if (strcmp(frz->path, path) == 0) {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            *rvp = 0;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte            break;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte        }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    mutex_exit(&_nsc_frz_sleep);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    return (0);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * static int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * _nsc_frz_open(char *path, int flag, blind_t *cdp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Dummy open function.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Description:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  This is the "Open" function for the I/O module.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  It is just a dummy.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/* ARGSUSED */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_open(path, flag, cdp)
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortechar *path;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteint flag;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forteblind_t *cdp;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte{
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    *cdp = 0;
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    return (0);
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte}
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * static int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * _nsc_frz_close()
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Dummy close function.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Description:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  This is the "Close" function for the I/O module.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  It is just a dummy.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_close() { return (0); }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte/*
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * static int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * _nsc_frz_attach()
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Attach a device to this i/o module.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Calling/Exit State:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  Returns EACCES in all cricumstances.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte * Description:
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  This function is called by the nsctl module when it wishes
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  to attach the device to this I/O module (ie. as part of
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  nsc_reserve() processing).  This function unconditionally
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  returns an error which forces the nsc_reserve() to fail, and
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte *  so no access to possible to the underlying device.
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte */
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic int
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte_nsc_frz_attach() { return (EACCES); }
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Fortestatic nsc_def_t _nsc_frz_def[] = {
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    "Open",     (uintptr_t)_nsc_frz_open,       0,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    "Close",    (uintptr_t)_nsc_frz_close,      0,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    "Attach",   (uintptr_t)_nsc_frz_attach,     0,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    "Provide",  0,              0,
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte    0,      0,              0
fcf3ce441efd61da9bb2884968af01cb7c1452ccJohn Forte};