root/usr/src/lib/libdiskmgt/common/path.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <fcntl.h>
#include <libdevinfo.h>
#include <stdlib.h>
#include <sys/sunddi.h>
#include <sys/types.h>

#include "libdiskmgt.h"
#include "disks_private.h"

static int              add_path_state(descriptor_t *dp, nvlist_t *attrs);
static int              add_wwn(descriptor_t *dp, nvlist_t *attrs);
static descriptor_t     **get_assoc_drives(descriptor_t *desc, int *errp);
static descriptor_t     **get_assoc_controllers(descriptor_t *desc, int *errp);
static char             *path_state_name(di_path_state_t st);

descriptor_t **
path_get_assoc_descriptors(descriptor_t *desc, dm_desc_type_t type, int *errp)
{
        switch (type) {
        case DM_DRIVE:
            return (get_assoc_drives(desc, errp));
        case DM_CONTROLLER:
            return (get_assoc_controllers(desc, errp));
        }

        *errp = EINVAL;
        return (NULL);
}

nvlist_t *
path_get_attributes(descriptor_t *dp, int *errp)
{
        path_t          *pp;
        nvlist_t        *attrs = NULL;

        pp = dp->p.path;

        if (nvlist_alloc(&attrs, NVATTRS, 0) != 0) {
            *errp = ENOMEM;
            return (NULL);
        }

        if (nvlist_add_string(attrs, DM_CTYPE, pp->ctype) != 0) {
            nvlist_free(attrs);
            *errp = ENOMEM;
            return (NULL);
        }

        /*
         * We add the path state and wwn attributes only for descriptors that
         * we got via their association to a specific drive (since these
         * attributes are drive specific).
         */
        if (dp->name != NULL) {
            if (add_path_state(dp, attrs) != 0) {
                nvlist_free(attrs);
                *errp = ENOMEM;
                return (NULL);
            }
            if (add_wwn(dp, attrs) != 0) {
                nvlist_free(attrs);
                *errp = ENOMEM;
                return (NULL);
            }
        }

        *errp = 0;
        return (attrs);
}

descriptor_t *
path_get_descriptor_by_name(char *name, int *errp)
{
        descriptor_t    **paths;
        int             i;
        descriptor_t    *path = NULL;

        paths = cache_get_descriptors(DM_PATH, errp);
        if (*errp != 0) {
            return (NULL);
        }

        for (i = 0; paths[i]; i++) {
            if (libdiskmgt_str_eq(name, paths[i]->p.path->name)) {
                path = paths[i];
            } else {
                /* clean up the unused descriptors */
                cache_free_descriptor(paths[i]);
            }
        }
        free(paths);

        if (path == NULL) {
            *errp = ENODEV;
        }

        return (path);
}

/* ARGSUSED */
descriptor_t **
path_get_descriptors(int filter[], int *errp)
{
        return (cache_get_descriptors(DM_PATH, errp));
}

char *
path_get_name(descriptor_t *desc)
{
        return (desc->p.path->name);
}

/* ARGSUSED */
nvlist_t *
path_get_stats(descriptor_t *dp, int stat_type, int *errp)
{
        /* There are no stat types defined for paths */
        *errp = EINVAL;
        return (NULL);
}

int
path_make_descriptors()
{
        int             error;
        controller_t    *cp;

        cp = cache_get_controllerlist();
        while (cp != NULL) {
            if (cp->paths != NULL) {
                int i;

                for (i = 0; cp->paths[i]; i++) {
                    cache_load_desc(DM_PATH, cp->paths[i], NULL, NULL, &error);
                    if (error != 0) {
                        return (error);
                    }
                }
            }
            cp = cp->next;
        }

        return (0);
}

/*
 * This is called when we have a name in the descriptor name field.  That
 * only will be the case when the descriptor was created by getting the
 * association from a drive to the path.  Since we filled in the name with
 * the drive device id in that case, we can use the device id to look up the
 * drive-path state.
 */
static int
add_path_state(descriptor_t *dp, nvlist_t *attrs)
{
        ddi_devid_t     devid;
        path_t          *pp;
        int             i;
        int             status = 0;

        if (devid_str_decode(dp->name, &devid, NULL) != 0) {
            return (0);
        }

        /* find the index of the correct drive assoc. */
        pp = dp->p.path;
        for (i = 0; pp->disks[i] && pp->states[i] != -1; i++) {
            if (pp->disks[i]->devid != NULL &&
                devid_compare(pp->disks[i]->devid, devid) == 0) {

                /* add the corresponding state */
                if (nvlist_add_string(attrs, DM_PATH_STATE,
                    path_state_name(pp->states[i])) != 0) {
                    status = ENOMEM;
                }
                break;
            }
        }
        devid_free(devid);

        return (status);
}

/*
 * This is called when we have a name in the descriptor name field.  That
 * only will be the case when the descriptor was created by getting the
 * association from a drive to the path.  Since we filled in the name with
 * the drive device id in that case, we can use the device id to look up the
 * drive wwn.
 */
static int
add_wwn(descriptor_t *dp, nvlist_t *attrs)
{
        ddi_devid_t     devid;
        path_t          *pp;
        int             i;
        int             status = 0;

        if (devid_str_decode(dp->name, &devid, NULL) != 0) {
            return (0);
        }

        /* find the index of the correct drive assoc. */
        pp = dp->p.path;
        for (i = 0; pp->disks[i] && pp->states[i] != -1; i++) {
            if (pp->disks[i]->devid != NULL &&
                devid_compare(pp->disks[i]->devid, devid) == 0) {

                /* add the corresponding state */
                if (nvlist_add_string(attrs, DM_WWN, pp->wwns[i]) != 0) {
                    status = ENOMEM;
                }
                break;
            }
        }
        devid_free(devid);

        return (status);
}

static descriptor_t **
get_assoc_controllers(descriptor_t *desc, int *errp)
{
        path_t          *pp;
        descriptor_t    **controllers;
        int             i;

        pp = desc->p.path;

        /* a path can have just one controller */

        controllers = (descriptor_t **)calloc(2, sizeof (descriptor_t *));
        if (controllers == NULL) {
            *errp = ENOMEM;
            return (NULL);
        }

        i = 0;
        if (pp->controller != NULL) {
            controllers[i++] = cache_get_desc(DM_CONTROLLER,
                pp->controller, NULL, NULL, errp);
            if (*errp != 0) {
                cache_free_descriptors(controllers);
                return (NULL);
            }
        }

        controllers[i] = NULL;

        *errp = 0;
        return (controllers);
}

static descriptor_t **
get_assoc_drives(descriptor_t *desc, int *errp)
{
        path_t          *pp;
        descriptor_t    **drives;
        int             cnt;
        int             i;

        pp = desc->p.path;

        /* Count how many we have. */
        for (cnt = 0; pp->disks[cnt]; cnt++);

        /* make the snapshot */
        drives = (descriptor_t **)calloc(cnt + 1, sizeof (descriptor_t *));
        if (drives == NULL) {
            *errp = ENOMEM;
            return (NULL);
        }

        for (i = 0; pp->disks[i]; i++) {
            drives[i] = cache_get_desc(DM_DRIVE, pp->disks[i], NULL, NULL,
                errp);
            if (*errp != 0) {
                cache_free_descriptors(drives);
                return (NULL);
            }
        }
        drives[i] = NULL;

        *errp = 0;
        return (drives);
}

static char *
path_state_name(di_path_state_t st)
{
        switch (st) {
            case DI_PATH_STATE_ONLINE:
                return ("online");
            case DI_PATH_STATE_STANDBY:
                return ("standby");
            case DI_PATH_STATE_OFFLINE:
                return ("offline");
            case DI_PATH_STATE_FAULT:
                return ("faulted");
        }
        return ("unknown");
}