/*
 * 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 (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2012 Milan Jurik. All rights reserved.
 * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
 * Copyright 2020 Joyent, Inc.
 */

#include <alloca.h>
#include <dirent.h>
#include <devid.h>
#include <fm/libdiskstatus.h>
#include <inttypes.h>
#include <pthread.h>
#include <strings.h>
#include <string.h>
#include <unistd.h>
#include <sys/dkio.h>
#include <sys/fm/protocol.h>
#include <sys/libdevid.h>
#include <sys/scsi/scsi_types.h>
#include <sys/byteorder.h>
#include <pthread.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/ctfs.h>
#include <libcontract.h>
#include <poll.h>
#include <sys/contract/device.h>
#include <libsysevent.h>
#include <sys/sysevent/eventdefs.h>
#include <scsi/plugins/ses/vendor/sun.h>

#include "disk.h"
#include "ses.h"

#define SES_VERSION     1

#define SES_STARTING_SUBCHASSIS 256     /* valid subchassis IDs are uint8_t */
#define NO_SUBCHASSIS   ((uint64_t)-1)

static int ses_snap_freq = 250;         /* in milliseconds */

#define SES_STATUS_UNAVAIL(s)   \
        ((s) == SES_ESC_UNSUPPORTED || (s) >= SES_ESC_NOT_INSTALLED)

#define HR_SECOND   1000000000

#define SES_INST_NOTSET         UINT64_MAX

/*
 * Because multiple SES targets can be part of a single chassis, we construct
 * our own hierarchy that takes this into account.  These SES targets may refer
 * to the same devices (multiple paths) or to different devices (managing
 * different portions of the space).  We arrange things into a
 * ses_enum_enclosure_t, which contains a set of ses targets, and a list of all
 * nodes found so far.
 */
typedef struct ses_alt_node {
        topo_list_t             san_link;
        ses_node_t              *san_node;
} ses_alt_node_t;

typedef struct ses_enum_node {
        topo_list_t             sen_link;
        ses_node_t              *sen_node;
        topo_list_t             sen_alt_nodes;
        uint64_t                sen_type;
        uint64_t                sen_instance;
        ses_enum_target_t       *sen_target;
} ses_enum_node_t;

typedef struct ses_enum_chassis {
        topo_list_t             sec_link;
        topo_list_t             sec_subchassis;
        topo_list_t             sec_nodes;
        topo_list_t             sec_targets;
        const char              *sec_csn;
        ses_node_t              *sec_enclosure;
        ses_enum_target_t       *sec_target;
        topo_instance_t         sec_instance;
        topo_instance_t         sec_scinstance;
        topo_instance_t         sec_maxinstance;
        boolean_t               sec_hasdev;
        boolean_t               sec_internal;
} ses_enum_chassis_t;

typedef struct ses_enum_data {
        topo_list_t             sed_devs;
        topo_list_t             sed_chassis;
        ses_enum_chassis_t      *sed_current;
        ses_enum_target_t       *sed_target;
        int                     sed_errno;
        char                    *sed_name;
        topo_mod_t              *sed_mod;
        topo_instance_t         sed_instance;
} ses_enum_data_t;

typedef struct sas_connector_phy_data {
        uint64_t    scpd_index;
        uint64_t    scpd_pm;
} sas_connector_phy_data_t;

typedef struct sas_connector_type {
        uint64_t    sct_type;
        char        *sct_name;
} sas_connector_type_t;

static const sas_connector_type_t sas_connector_type_list[] = {
        {   0x0, "Information unknown"  },
        {   0x1, "External SAS 4x receptacle (see SAS-2 and SFF-8470)"  },
        {   0x2, "Exteranl Mini SAS 4x receptacle (see SAS-2 and SFF-8088)" },
        {   0x3, "QSFP+ receptacle (see SAS-2.1 and SFF-8436)" },
        {   0x4, "Mini SAS 4x active receptacle (see SAS-2.1 and SFF-8088)" },
        {   0x5, "Mini SAS HD 4x receptacle (see SAS-2.1 and SFF-8644)" },
        {   0x6, "Mini SAS HD 8x receptacle (see SAS-2.1 and SFF-8644)" },
        {   0x7, "Mini SAS HD 16x receptacle (see SAS-2.1 and SFF-8644)" },
        {   0xF, "Vendor-specific external connector"   },
        {   0x10, "Internal wide SAS 4i plug (see SAS-2 and SFF-8484)"  },
        {   0x11,
        "Internal wide Mini SAS 4i receptacle (see SAS-2 and SFF-8087)" },
        {   0x12, "Mini SAS HD 4i receptacle (see SAS-2.1 and SFF-8643)" },
        {   0x20, "Internal SAS Drive receptacle (see SAS-2 and SFF-8482)" },
        {   0x21, "Internal SATA host plug (see SAS-2 and SATA-2)"      },
        {   0x22, "Internal SAS Drive plug (see SAS-2 and SFF-8482)"    },
        {   0x23, "Internal SATA device plug (see SAS-2 and SATA-2)"    },
        {   0x24, "Micro SAS receptacle (see SAS-2.14)" },
        {   0x25, "Micro SATA device plug (see SAS-2.1 and SATA)"       },
        {   0x26, "Micro SAS plug (see SAS-2.1 and SFF-8486)"   },
        {   0x27, "Micro SAS/SATA plug (see SAS-2.1 and SFF-8486)"      },
        {   0x28,
        "12 Gb/s SAS Drive backplane receptacle (see SAS-34 and SFF-8680)" },
        {   0x29, "12Gb/s SAS Drive Plug (see SAS-3 and SFF-8680)"      },
        {   0x2A, "Multifunction 12 Gb/s 6x Unshielded receptacle connector "
                "receptacle (see SAS-3 and SFF-8639)"   },
        {   0x2B, "Multifunction 12 Gb/s 6x Unshielded receptable connector "
                "plug (see SAS-3 and SFF-8639)" },
        {   0x2F, "Internal SAS virtual connector"  },
        {   0x3F, "Vendor-specific internal connector"  },
        {   0x70, "Other Vendor-specific connector"     },
        {   0x71, "Other Vendor-specific connector"     },
        {   0x72, "Other Vendor-specific connector"     },
        {   0x73, "Other Vendor-specific connector"     },
        {   0x74, "Other Vendor-specific connector"     },
        {   0x75, "Other Vendor-specific connector"     },
        {   0x76, "Other Vendor-specific connector"     },
        {   0x77, "Other Vendor-specific connector"     },
        {   0x78, "Other Vendor-specific connector"     },
        {   0x79, "Other Vendor-specific connector"     },
        {   0x7A, "Other Vendor-specific connector"     },
        {   0x7B, "Other Vendor-specific connector"     },
        {   0x7C, "Other Vendor-specific connector"     },
        {   0x7D, "Other Vendor-specific connector"     },
        {   0x7E, "Other Vendor-specific connector"     },
        {   0x7F, "Other Vendor-specific connector"     },
        {   0x80, "Not Defined" }
};

#define SAS_CONNECTOR_TYPE_CODE_NOT_DEFINED  0x80
#define SAS_CONNECTOR_TYPE_NOT_DEFINED \
        "Connector type not defined by SES-2 standard"
#define SAS_CONNECTOR_TYPE_RESERVED \
        "Connector type reserved by SES-2 standard"

typedef struct phys_enum_type {
        uint64_t    pet_type;
        char        *pet_nodename;
        char        *pet_defaultlabel;
        boolean_t   pet_dorange;
} phys_enum_type_t;

static const phys_enum_type_t phys_enum_type_list[] = {
        {   SES_ET_ARRAY_DEVICE, BAY, "BAY", B_TRUE  },
        {   SES_ET_COOLING, FAN, "FAN", B_TRUE  },
        {   SES_ET_DEVICE, BAY, "BAY", B_TRUE  },
        {   SES_ET_ESC_ELECTRONICS, CONTROLLER, "CONTROLLER", B_TRUE  },
        {   SES_ET_POWER_SUPPLY, PSU, "PSU", B_TRUE  },
        {   SES_ET_SUNW_FANBOARD, FANBOARD, "FANBOARD", B_TRUE  },
        {   SES_ET_SUNW_FANMODULE, FANMODULE, "FANMODULE", B_TRUE  },
        {   SES_ET_SUNW_POWERBOARD, POWERBOARD, "POWERBOARD", B_TRUE  },
        {   SES_ET_SUNW_POWERMODULE, POWERMODULE, "POWERMODULE", B_TRUE  }
};

#define N_PHYS_ENUM_TYPES (sizeof (phys_enum_type_list) / \
        sizeof (phys_enum_type_list[0]))

/*
 * Structure for the hierarchical tree for element nodes.
 */
typedef struct ses_phys_tree {
    ses_node_t  *spt_snode;
    ses_enum_node_t     *spt_senumnode;
    boolean_t   spt_isfru;
    uint64_t    spt_eonlyindex;
    uint64_t    spt_cindex;
    uint64_t    spt_pindex;
    uint64_t    spt_maxinst;
    struct ses_phys_tree    *spt_parent;
    struct ses_phys_tree    *spt_child;
    struct ses_phys_tree    *spt_sibling;
    tnode_t     *spt_tnode;
} ses_phys_tree_t;

typedef enum {
        SES_NEW_CHASSIS         = 0x1,
        SES_NEW_SUBCHASSIS      = 0x2,
        SES_DUP_CHASSIS         = 0x4,
        SES_DUP_SUBCHASSIS      = 0x8
} ses_chassis_type_e;

static const topo_pgroup_info_t smp_pgroup = {
        TOPO_PGROUP_SMP,
        TOPO_STABILITY_PRIVATE,
        TOPO_STABILITY_PRIVATE,
        1
};

static const topo_pgroup_info_t ses_pgroup = {
        TOPO_PGROUP_SES,
        TOPO_STABILITY_PRIVATE,
        TOPO_STABILITY_PRIVATE,
        1
};

static int ses_present(topo_mod_t *, tnode_t *, topo_version_t, nvlist_t *,
    nvlist_t **);
static int ses_contains(topo_mod_t *, tnode_t *, topo_version_t, nvlist_t *,
    nvlist_t **);

static const topo_method_t ses_component_methods[] = {
        { TOPO_METH_PRESENT, TOPO_METH_PRESENT_DESC,
            TOPO_METH_PRESENT_VERSION0, TOPO_STABILITY_INTERNAL, ses_present },
        { TOPO_METH_FAC_ENUM, TOPO_METH_FAC_ENUM_DESC, 0,
            TOPO_STABILITY_INTERNAL, ses_node_enum_facility },
        { TOPO_METH_SENSOR_FAILURE, TOPO_METH_SENSOR_FAILURE_DESC,
            TOPO_METH_SENSOR_FAILURE_VERSION, TOPO_STABILITY_INTERNAL,
            topo_method_sensor_failure },
        { NULL }
};

#define TOPO_METH_SMCI_4U36_LABEL               "smci_4u36_bay_label"
#define TOPO_METH_SMCI_4U36_LABEL_DESC  \
        "compute bay labels on SMCI 4U36 storage platform variants"
#define TOPO_METH_SMCI_4U36_LABEL_VERSION       0
static int smci_4u36_bay_label(topo_mod_t *, tnode_t *, topo_version_t,
    nvlist_t *, nvlist_t **);

static const topo_method_t ses_bay_methods[] = {
        { TOPO_METH_FAC_ENUM, TOPO_METH_FAC_ENUM_DESC, 0,
            TOPO_STABILITY_INTERNAL, ses_node_enum_facility },
        { TOPO_METH_OCCUPIED, TOPO_METH_OCCUPIED_DESC,
            TOPO_METH_OCCUPIED_VERSION, TOPO_STABILITY_INTERNAL,
            topo_mod_hc_occupied },
        { TOPO_METH_SMCI_4U36_LABEL, TOPO_METH_SMCI_4U36_LABEL_DESC,
            TOPO_METH_SMCI_4U36_LABEL_VERSION, TOPO_STABILITY_INTERNAL,
            smci_4u36_bay_label },
        { NULL }
};

static const topo_method_t ses_recep_methods[] = {
        { TOPO_METH_OCCUPIED, TOPO_METH_OCCUPIED_DESC,
            TOPO_METH_OCCUPIED_VERSION, TOPO_STABILITY_INTERNAL,
            topo_mod_hc_occupied },
        { NULL }
};

static const topo_method_t ses_enclosure_methods[] = {
        { TOPO_METH_CONTAINS, TOPO_METH_CONTAINS_DESC,
            TOPO_METH_CONTAINS_VERSION, TOPO_STABILITY_INTERNAL, ses_contains },
        { TOPO_METH_FAC_ENUM, TOPO_METH_FAC_ENUM_DESC, 0,
            TOPO_STABILITY_INTERNAL, ses_enc_enum_facility },
        { NULL }
};

/*
 * The bay_label_overrides table can be used to map a server product ID to a
 * topo method that will be invoked to override the value of the label property
 * for all bay nodes.  By default the property value is static, derived from
 * the corresponding SES array device element's descriptor string.
 */
typedef struct ses_label_overrides {
        const char *slbl_product;
        const char *slbl_mname;
} ses_label_overrides_t;

/*
 * This table covers three generations of SMCI's 4U 36-bay storage server
 * (and the Joyent-branded versions).  There was also an Ivy Bridge variant
 * which has been omitted due to an inability to find one to test on.
 */
static const ses_label_overrides_t bay_label_overrides[] = {
        /* Sandy Bridge variant */
        { "SSG-6047R-E1R36L", TOPO_METH_SMCI_4U36_LABEL },
        { "Joyent-Storage-Platform-5001", TOPO_METH_SMCI_4U36_LABEL },

        /* Broadwell variant */
        { "SSG-6048R-E1CR36L", TOPO_METH_SMCI_4U36_LABEL },
        { "Joyent-Storage-Platform-7001", TOPO_METH_SMCI_4U36_LABEL },

        /* Skylake variant */
        { "SSG-6049P-E1CR36L", TOPO_METH_SMCI_4U36_LABEL },
        { "Joyent-S10G5", TOPO_METH_SMCI_4U36_LABEL }
};

#define N_BAY_LBL_OVERRIDES (sizeof (bay_label_overrides) / \
        sizeof (bay_label_overrides[0]))

/*
 * Functions for tracking ses devices which we were unable to open. We retry
 * these at regular intervals using ses_recheck_dir() and if we find that we
 * can now open any of them then we send a sysevent to indicate that a new topo
 * snapshot should be taken.
 */
typedef struct ses_open_fail_list {
        struct ses_open_fail_list       *sof_next;
        char                            *sof_path;
} ses_open_fail_list_t;

static ses_open_fail_list_t *ses_sofh;
static pthread_mutex_t ses_sofmt;
static void ses_ct_print(char *ptr);

static void
ses_recheck_dir()
{
        ses_target_t *target;
        sysevent_id_t eid;
        char buf[80];
        ses_open_fail_list_t *sof;

        /*
         * check list of "unable to open" devices
         */
        (void) pthread_mutex_lock(&ses_sofmt);
        for (sof = ses_sofh; sof != NULL; sof = sof->sof_next) {
                /*
                 * see if we can open it now
                 */
                if ((target = ses_open(LIBSES_VERSION,
                    sof->sof_path)) == NULL) {
                        (void) snprintf(buf, sizeof (buf),
                            "recheck_dir - still can't open %s", sof->sof_path);
                        ses_ct_print(buf);
                        continue;
                }

                /*
                 * ok - better force a new snapshot
                 */
                (void) snprintf(buf, sizeof (buf),
                    "recheck_dir - can now open %s", sof->sof_path);
                ses_ct_print(buf);
                (void) sysevent_post_event(EC_PLATFORM, ESC_PLATFORM_SP_RESET,
                    SUNW_VENDOR, "fmd", NULL, &eid);
                ses_close(target);
                break;
        }
        (void) pthread_mutex_unlock(&ses_sofmt);
}

static void
ses_sof_alloc(topo_mod_t *mod, char *path)
{
        ses_open_fail_list_t *sof;

        (void) pthread_mutex_lock(&ses_sofmt);
        sof = topo_mod_zalloc(mod, sizeof (*sof));
        topo_mod_dprintf(mod, "sof_alloc %s", path);
        sof->sof_path = path;
        sof->sof_next = ses_sofh;
        ses_sofh = sof;
        (void) pthread_mutex_unlock(&ses_sofmt);
}

static void
ses_sof_freeall(topo_mod_t *mod)
{
        ses_open_fail_list_t *sof, *next_sof;

        (void) pthread_mutex_lock(&ses_sofmt);
        for (sof = ses_sofh; sof != NULL; sof = next_sof) {
                next_sof = sof->sof_next;
                topo_mod_dprintf(mod, "sof_freeall %s", sof->sof_path);
                topo_mod_strfree(mod, sof->sof_path);
                topo_mod_free(mod, sof, sizeof (*sof));
        }
        ses_sofh = NULL;
        (void) pthread_mutex_unlock(&ses_sofmt);
}

/*
 * functions for verifying that the ses_enum_target_t held in a device
 * contract's cookie field is still valid (it may have been freed by
 * ses_release()).
 */
typedef struct ses_stp_list {
        struct ses_stp_list     *ssl_next;
        ses_enum_target_t       *ssl_tgt;
} ses_stp_list_t;

static ses_stp_list_t *ses_sslh;
static pthread_mutex_t ses_sslmt;

static void
ses_ssl_alloc(topo_mod_t *mod, ses_enum_target_t *stp)
{
        ses_stp_list_t *ssl;

        (void) pthread_mutex_lock(&ses_sslmt);
        ssl = topo_mod_zalloc(mod, sizeof (*ssl));
        topo_mod_dprintf(mod, "ssl_alloc %p", stp);
        ssl->ssl_tgt = stp;
        ssl->ssl_next = ses_sslh;
        ses_sslh = ssl;
        (void) pthread_mutex_unlock(&ses_sslmt);
}

static void
ses_ssl_free(topo_mod_t *mod, ses_enum_target_t *stp)
{
        ses_stp_list_t *ssl, *prev_ssl;

        (void) pthread_mutex_lock(&ses_sslmt);
        prev_ssl = NULL;
        for (ssl = ses_sslh; ssl != NULL; ssl = ssl->ssl_next) {
                if (ssl->ssl_tgt == stp) {
                        topo_mod_dprintf(mod, "ssl_free %p", ssl->ssl_tgt);
                        if (prev_ssl == NULL)
                                ses_sslh = ssl->ssl_next;
                        else
                                prev_ssl->ssl_next = ssl->ssl_next;
                        topo_mod_free(mod, ssl, sizeof (*ssl));
                        break;
                }
                prev_ssl = ssl;
        }
        (void) pthread_mutex_unlock(&ses_sslmt);
}

static int
ses_ssl_valid(ses_enum_target_t *stp)
{
        ses_stp_list_t *ssl;

        for (ssl = ses_sslh; ssl != NULL; ssl = ssl->ssl_next)
                if (ssl->ssl_tgt == stp)
                        return (1);
        return (0);
}

/*
 * Functions for creating and destroying a background thread
 * (ses_contract_thread) used for detecting when ses devices have been
 * retired/unretired.
 */
static struct ses_thread_s {
        pthread_mutex_t mt;
        pthread_t tid;
        int thr_sig;
        int doexit;
        int count;
} sesthread = {
        PTHREAD_MUTEX_INITIALIZER,
        0,
        SIGTERM,
        0,
        0
};

typedef struct ses_mod_list {
        struct ses_mod_list     *smod_next;
        topo_mod_t              *smod_mod;
} ses_mod_list_t;

static ses_mod_list_t *ses_smod;

static void
ses_ct_print(char *ptr)
{
        (void) pthread_mutex_lock(&sesthread.mt);
        if (ses_smod != NULL && ses_smod->smod_mod != NULL)
                topo_mod_dprintf(ses_smod->smod_mod, ptr);
        (void) pthread_mutex_unlock(&sesthread.mt);
}

/*ARGSUSED*/
static void *
ses_contract_thread(void *arg)
{
        int efd, ctlfd, statfd;
        ct_evthdl_t ev;
        ctevid_t evid;
        uint_t event;
        char path[PATH_MAX];
        char buf[80];
        ses_enum_target_t *stp;
        ct_stathdl_t stathdl;
        ctid_t ctid;
        struct pollfd fds;
        int pollret;
        sigset_t sigset;

        ses_ct_print("start contract event thread");
        efd = open64(CTFS_ROOT "/device/pbundle", O_RDONLY);
        fds.fd = efd;
        fds.events = POLLIN;
        fds.revents = 0;
        (void) sigaddset(&sigset, sesthread.thr_sig);
        (void) pthread_sigmask(SIG_UNBLOCK, &sigset, NULL);
        for (;;) {
                /* check if we've been asked to exit */
                (void) pthread_mutex_lock(&sesthread.mt);
                if (sesthread.doexit) {
                        (void) pthread_mutex_unlock(&sesthread.mt);
                        break;
                }
                (void) pthread_mutex_unlock(&sesthread.mt);

                /* poll until an event arrives */
                if ((pollret = poll(&fds, 1, 10000)) <= 0) {
                        if (pollret == 0)
                                ses_recheck_dir();
                        continue;
                }

                /* read the event */
                (void) pthread_mutex_lock(&ses_sslmt);
                ses_ct_print("read contract event");
                if (ct_event_read(efd, &ev) != 0) {
                        (void) pthread_mutex_unlock(&ses_sslmt);
                        continue;
                }

                /* see if it is an event we are expecting */
                ctid = ct_event_get_ctid(ev);
                (void) snprintf(buf, sizeof (buf),
                    "got contract event ctid=%d", ctid);
                ses_ct_print(buf);
                event = ct_event_get_type(ev);
                if (event != CT_DEV_EV_OFFLINE && event != CT_EV_NEGEND) {
                        (void) snprintf(buf, sizeof (buf),
                            "bad contract event %x", event);
                        ses_ct_print(buf);
                        ct_event_free(ev);
                        (void) pthread_mutex_unlock(&ses_sslmt);
                        continue;
                }

                /* find target pointer saved in cookie */
                evid = ct_event_get_evid(ev);
                (void) snprintf(path, PATH_MAX, CTFS_ROOT "/device/%ld/status",
                    ctid);
                statfd = open64(path, O_RDONLY);
                (void) ct_status_read(statfd, CTD_COMMON, &stathdl);
                stp = (ses_enum_target_t *)(uintptr_t)
                    ct_status_get_cookie(stathdl);
                ct_status_free(stathdl);
                (void) close(statfd);

                /* check if target pointer is still valid */
                if (ses_ssl_valid(stp) == 0) {
                        (void) snprintf(buf, sizeof (buf),
                            "contract already abandoned %x", event);
                        ses_ct_print(buf);
                        (void) snprintf(path, PATH_MAX,
                            CTFS_ROOT "/device/%ld/ctl", ctid);
                        ctlfd = open64(path, O_WRONLY);
                        if (event != CT_EV_NEGEND)
                                (void) ct_ctl_ack(ctlfd, evid);
                        else
                                (void) ct_ctl_abandon(ctlfd);
                        (void) close(ctlfd);
                        ct_event_free(ev);
                        (void) pthread_mutex_unlock(&ses_sslmt);
                        continue;
                }

                /* find control device for ack/abandon */
                (void) pthread_mutex_lock(&stp->set_lock);
                (void) snprintf(path, PATH_MAX, CTFS_ROOT "/device/%ld/ctl",
                    ctid);
                ctlfd = open64(path, O_WRONLY);
                if (event != CT_EV_NEGEND) {
                        /* if this is an offline event, do the offline */
                        ses_ct_print("got contract offline event");
                        if (stp->set_target) {
                                ses_ct_print("contract thread rele");
                                ses_snap_rele(stp->set_snap);
                                ses_close(stp->set_target);
                                stp->set_target = NULL;
                        }
                        (void) ct_ctl_ack(ctlfd, evid);
                } else {
                        /* if this is the negend, then abandon the contract */
                        ses_ct_print("got contract negend");
                        if (stp->set_ctid) {
                                (void) snprintf(buf, sizeof (buf),
                                    "abandon old contract %d", stp->set_ctid);
                                ses_ct_print(buf);
                                stp->set_ctid = 0;
                        }
                        (void) ct_ctl_abandon(ctlfd);
                }
                (void) close(ctlfd);
                (void) pthread_mutex_unlock(&stp->set_lock);
                ct_event_free(ev);
                (void) pthread_mutex_unlock(&ses_sslmt);
        }
        (void) close(efd);
        return (NULL);
}

int
find_thr_sig(void)
{
        int i;
        sigset_t oset, rset;
        int sig[] = {SIGTERM, SIGUSR1, SIGUSR2};
        int sig_sz = sizeof (sig) / sizeof (int);
        int rc = SIGTERM;

        /* prefered set of signals that are likely used to terminate threads */
        (void) sigemptyset(&oset);
        (void) pthread_sigmask(SIG_SETMASK, NULL, &oset);
        for (i = 0; i < sig_sz; i++) {
                if (sigismember(&oset, sig[i]) == 0) {
                        return (sig[i]);
                }
        }

        /* reserved set of signals that are not allowed to terminate thread */
        (void) sigemptyset(&rset);
        (void) sigaddset(&rset, SIGABRT);
        (void) sigaddset(&rset, SIGKILL);
        (void) sigaddset(&rset, SIGSTOP);
        (void) sigaddset(&rset, SIGCANCEL);

        /* Find signal that is not masked and not in the reserved list. */
        for (i = 1; i < MAXSIG; i++) {
                if (sigismember(&rset, i) == 1) {
                        continue;
                }
                if (sigismember(&oset, i) == 0) {
                        return (i);
                }
        }

        return (rc);
}

/*ARGSUSED*/
static void
ses_handler(int sig)
{
}

static void
ses_thread_init(topo_mod_t *mod)
{
        pthread_attr_t *attr = NULL;
        struct sigaction act;
        ses_mod_list_t *smod;

        (void) pthread_mutex_lock(&sesthread.mt);
        sesthread.count++;
        smod = topo_mod_zalloc(mod, sizeof (*smod));
        smod->smod_mod = mod;
        smod->smod_next = ses_smod;
        ses_smod = smod;
        if (sesthread.tid == 0) {
                /* find a suitable signal to use for killing the thread below */
                sesthread.thr_sig = find_thr_sig();

                /* if don't have a handler for this signal, create one */
                (void) sigaction(sesthread.thr_sig, NULL, &act);
                if (act.sa_handler == SIG_DFL || act.sa_handler == SIG_IGN)
                        act.sa_handler = ses_handler;
                (void) sigaction(sesthread.thr_sig, &act, NULL);

                /* create a thread to listen for offline events */
                (void) pthread_create(&sesthread.tid,
                    attr, ses_contract_thread, NULL);
        }
        (void) pthread_mutex_unlock(&sesthread.mt);
}

static void
ses_thread_fini(topo_mod_t *mod)
{
        ses_mod_list_t *smod, *prev_smod;

        (void) pthread_mutex_lock(&sesthread.mt);
        prev_smod = NULL;
        for (smod = ses_smod; smod != NULL; smod = smod->smod_next) {
                if (smod->smod_mod == mod) {
                        if (prev_smod == NULL)
                                ses_smod = smod->smod_next;
                        else
                                prev_smod->smod_next = smod->smod_next;
                        topo_mod_free(mod, smod, sizeof (*smod));
                        break;
                }
                prev_smod = smod;
        }
        if (--sesthread.count > 0) {
                (void) pthread_mutex_unlock(&sesthread.mt);
                return;
        }
        sesthread.doexit = 1;
        (void) pthread_mutex_unlock(&sesthread.mt);
        (void) pthread_kill(sesthread.tid, sesthread.thr_sig);
        (void) pthread_join(sesthread.tid, NULL);
        sesthread.tid = 0;
}

static void
ses_create_contract(topo_mod_t *mod, ses_enum_target_t *stp)
{
        int tfd, len, rval;
        char link_path[PATH_MAX];

        stp->set_ctid = 0;

        /* convert "/dev" path into "/devices" path */
        if ((len = readlink(stp->set_devpath, link_path, PATH_MAX)) < 0) {
                topo_mod_dprintf(mod, "readlink failed");
                return;
        }
        link_path[len] = '\0';

        /* set up template to create new contract */
        tfd = open64(CTFS_ROOT "/device/template", O_RDWR);
        (void) ct_tmpl_set_critical(tfd, CT_DEV_EV_OFFLINE);
        (void) ct_tmpl_set_cookie(tfd, (uint64_t)(uintptr_t)stp);

        /* strip "../../devices" off the front and create the contract */
        if ((rval = ct_dev_tmpl_set_minor(tfd, &link_path[13])) != 0)
                topo_mod_dprintf(mod, "failed to set minor %s rval = %d",
                    &link_path[13], rval);
        else if ((rval = ct_tmpl_create(tfd, &stp->set_ctid)) != 0)
                topo_mod_dprintf(mod, "failed to create ctid rval = %d", rval);
        else
                topo_mod_dprintf(mod, "created ctid=%" _PRIdID, stp->set_ctid);
        (void) close(tfd);
}

static void
ses_target_free(topo_mod_t *mod, ses_enum_target_t *stp)
{
        if (--stp->set_refcount == 0) {
                /* check if already closed due to contract offline request */
                (void) pthread_mutex_lock(&stp->set_lock);
                if (stp->set_target) {
                        ses_snap_rele(stp->set_snap);
                        ses_close(stp->set_target);
                        stp->set_target = NULL;
                }
                if (stp->set_ctid) {
                        int ctlfd;
                        char path[PATH_MAX];

                        topo_mod_dprintf(mod, "abandon old contract %" _PRIdID,
                            stp->set_ctid);
                        (void) snprintf(path, PATH_MAX,
                            CTFS_ROOT "/device/%" _PRIdID "/ctl",
                            stp->set_ctid);
                        ctlfd = open64(path, O_WRONLY);
                        (void) ct_ctl_abandon(ctlfd);
                        (void) close(ctlfd);
                        stp->set_ctid = 0;
                }
                (void) pthread_mutex_unlock(&stp->set_lock);
                ses_ssl_free(mod, stp);
                topo_mod_strfree(mod, stp->set_devpath);
                topo_mod_free(mod, stp, sizeof (ses_enum_target_t));
        }
}

static void
ses_data_free(ses_enum_data_t *sdp, ses_enum_chassis_t *pcp)
{
        topo_mod_t *mod = sdp->sed_mod;
        ses_enum_chassis_t *cp;
        ses_enum_node_t *np;
        ses_enum_target_t *tp;
        ses_alt_node_t *ap;
        topo_list_t *cpl;


        if (pcp != NULL)
                cpl = &pcp->sec_subchassis;
        else
                cpl = &sdp->sed_chassis;

        while ((cp = topo_list_next(cpl)) != NULL) {
                topo_list_delete(cpl, cp);

                while ((np = topo_list_next(&cp->sec_nodes)) != NULL) {
                        while ((ap = topo_list_next(&np->sen_alt_nodes)) !=
                            NULL) {
                                topo_list_delete(&np->sen_alt_nodes, ap);
                                topo_mod_free(mod, ap, sizeof (ses_alt_node_t));
                        }
                        topo_list_delete(&cp->sec_nodes, np);
                        topo_mod_free(mod, np, sizeof (ses_enum_node_t));
                }

                while ((tp = topo_list_next(&cp->sec_targets)) != NULL) {
                        topo_list_delete(&cp->sec_targets, tp);
                        ses_target_free(mod, tp);
                }

                topo_mod_free(mod, cp, sizeof (ses_enum_chassis_t));
        }

        if (pcp == NULL) {
                dev_list_free(mod, &sdp->sed_devs);
                topo_mod_free(mod, sdp, sizeof (ses_enum_data_t));
        }
}

/*
 * For enclosure nodes, we have a special contains method.  By default, the hc
 * walker will compare the node name and instance number to determine if an
 * FMRI matches.  For enclosures where the enumeration order is impossible to
 * predict, we instead use the chassis-id as a unique identifier, and ignore
 * the instance number.
 */
static int
fmri_contains(topo_mod_t *mod, nvlist_t *nv1, nvlist_t *nv2)
{
        uint8_t v1, v2;
        nvlist_t **hcp1, **hcp2;
        int err, i;
        uint_t nhcp1, nhcp2;
        nvlist_t *a1, *a2;
        char *c1, *c2;
        int mindepth;

        if (nvlist_lookup_uint8(nv1, FM_VERSION, &v1) != 0 ||
            nvlist_lookup_uint8(nv2, FM_VERSION, &v2) != 0 ||
            v1 > FM_HC_SCHEME_VERSION || v2 > FM_HC_SCHEME_VERSION)
                return (topo_mod_seterrno(mod, EMOD_FMRI_VERSION));

        err = nvlist_lookup_nvlist_array(nv1, FM_FMRI_HC_LIST, &hcp1, &nhcp1);
        err |= nvlist_lookup_nvlist_array(nv2, FM_FMRI_HC_LIST, &hcp2, &nhcp2);
        if (err != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));

        /*
         * If the chassis-id doesn't match, then these FMRIs are not
         * equivalent.  If one of the FMRIs doesn't have a chassis ID, then we
         * have no choice but to fall back to the instance ID.
         */
        if (nvlist_lookup_nvlist(nv1, FM_FMRI_AUTHORITY, &a1) == 0 &&
            nvlist_lookup_nvlist(nv2, FM_FMRI_AUTHORITY, &a2) == 0 &&
            nvlist_lookup_string(a1, FM_FMRI_AUTH_CHASSIS, &c1) == 0 &&
            nvlist_lookup_string(a2, FM_FMRI_AUTH_CHASSIS, &c2) == 0) {
                if (strcmp(c1, c2) != 0)
                        return (0);

                mindepth = 1;
        } else {
                mindepth = 0;
        }

        if (nhcp2 < nhcp1)
                return (0);

        for (i = 0; i < nhcp1; i++) {
                char *nm1 = NULL;
                char *nm2 = NULL;
                char *id1 = NULL;
                char *id2 = NULL;

                (void) nvlist_lookup_string(hcp1[i], FM_FMRI_HC_NAME, &nm1);
                (void) nvlist_lookup_string(hcp2[i], FM_FMRI_HC_NAME, &nm2);
                (void) nvlist_lookup_string(hcp1[i], FM_FMRI_HC_ID, &id1);
                (void) nvlist_lookup_string(hcp2[i], FM_FMRI_HC_ID, &id2);
                if (nm1 == NULL || nm2 == NULL || id1 == NULL || id2 == NULL)
                        return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));

                if (strcmp(nm1, nm2) == 0 &&
                    (i < mindepth || strcmp(id1, id2) == 0))
                        continue;

                return (0);
        }

        return (1);
}

/*ARGSUSED*/
static int
ses_contains(topo_mod_t *mod, tnode_t *tn, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        int ret;
        nvlist_t *nv1, *nv2;

        if (version > TOPO_METH_CONTAINS_VERSION)
                return (topo_mod_seterrno(mod, EMOD_VER_NEW));

        if (nvlist_lookup_nvlist(in, TOPO_METH_FMRI_ARG_FMRI, &nv1) != 0 ||
            nvlist_lookup_nvlist(in, TOPO_METH_FMRI_ARG_SUBFMRI, &nv2) != 0)
                return (topo_mod_seterrno(mod, EMOD_METHOD_INVAL));

        ret = fmri_contains(mod, nv1, nv2);
        if (ret < 0)
                return (-1);

        if (topo_mod_nvalloc(mod, out, NV_UNIQUE_NAME) == 0) {
                if (nvlist_add_uint32(*out, TOPO_METH_CONTAINS_RET,
                    ret) == 0)
                        return (0);
                else
                        nvlist_free(*out);
        }

        return (-1);

}

/*
 * Return a current instance of the node.  This is somewhat complicated because
 * we need to take a new snapshot in order to get the new data, but we don't
 * want to be constantly taking SES snapshots if the consumer is going to do a
 * series of queries.  So we adopt the strategy of assuming that the SES state
 * is not going to be rapidly changing, and limit our snapshot frequency to
 * some defined bounds.
 */
ses_node_t *
ses_node_lock(topo_mod_t *mod, tnode_t *tn)
{
        ses_enum_target_t *tp = topo_node_getspecific(tn);
        hrtime_t now;
        ses_snap_t *snap;
        int err;
        uint64_t nodeid;
        ses_node_t *np;

        if (tp == NULL) {
                (void) topo_mod_seterrno(mod, EMOD_METHOD_NOTSUP);
                return (NULL);
        }

        (void) pthread_mutex_lock(&tp->set_lock);

        /*
         * Determine if we need to take a new snapshot.
         */
        now = gethrtime();

        if (tp->set_target == NULL) {
                /*
                 * We may have closed the device but not yet abandoned the
                 * contract (ie we've had the offline event but not yet the
                 * negend). If so, just return failure.
                 */
                if (tp->set_ctid != 0) {
                        (void) topo_mod_seterrno(mod, EMOD_METHOD_NOTSUP);
                        (void) pthread_mutex_unlock(&tp->set_lock);
                        return (NULL);
                }

                /*
                 * The device has been closed due to a contract offline
                 * request, then we need to reopen it and create a new contract.
                 */
                if ((tp->set_target =
                    ses_open(LIBSES_VERSION, tp->set_devpath)) == NULL) {
                        sysevent_id_t eid;

                        (void) topo_mod_seterrno(mod, EMOD_METHOD_NOTSUP);
                        (void) pthread_mutex_unlock(&tp->set_lock);
                        topo_mod_dprintf(mod, "recheck_dir - "
                            "can no longer open %s", tp->set_devpath);
                        (void) sysevent_post_event(EC_PLATFORM,
                            ESC_PLATFORM_SP_RESET, SUNW_VENDOR, "fmd", NULL,
                            &eid);
                        return (NULL);
                }
                topo_mod_dprintf(mod, "reopen contract");
                ses_create_contract(mod, tp);
                tp->set_snap = ses_snap_hold(tp->set_target);
                tp->set_snaptime = gethrtime();
        } else if (now - tp->set_snaptime > (ses_snap_freq * 1000 * 1000) &&
            (snap = ses_snap_new(tp->set_target)) != NULL) {
                if (ses_snap_generation(snap) !=
                    ses_snap_generation(tp->set_snap)) {
                        /*
                         * If we find ourselves in this situation, we're in
                         * trouble.  The generation count has changed, which
                         * indicates that our current topology is out of date.
                         * But we need to consult the new topology in order to
                         * determine presence at this moment in time.  We can't
                         * go back and change the topo snapshot in situ, so
                         * we'll just have to fail the call in this unlikely
                         * scenario.
                         */
                        ses_snap_rele(snap);
                        (void) topo_mod_seterrno(mod, EMOD_METHOD_NOTSUP);
                        (void) pthread_mutex_unlock(&tp->set_lock);
                        return (NULL);
                } else {
                        ses_snap_rele(tp->set_snap);
                        tp->set_snap = snap;
                }
                tp->set_snaptime = gethrtime();
        }

        snap = tp->set_snap;

        verify(topo_prop_get_uint64(tn, TOPO_PGROUP_SES,
            TOPO_PROP_NODE_ID, &nodeid, &err) == 0);
        verify((np = ses_node_lookup(snap, nodeid)) != NULL);

        return (np);
}

/*ARGSUSED*/
void
ses_node_unlock(topo_mod_t *mod, tnode_t *tn)
{
        ses_enum_target_t *tp = topo_node_getspecific(tn);

        verify(tp != NULL);

        (void) pthread_mutex_unlock(&tp->set_lock);
}

/*
 * Determine if the element is present.
 */
/*ARGSUSED*/
static int
ses_present(topo_mod_t *mod, tnode_t *tn, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        boolean_t present;
        ses_node_t *np;
        nvlist_t *props, *nvl;
        uint64_t status;

        if ((np = ses_node_lock(mod, tn)) == NULL)
                return (-1);

        verify((props = ses_node_props(np)) != NULL);
        verify(nvlist_lookup_uint64(props,
            SES_PROP_STATUS_CODE, &status) == 0);

        ses_node_unlock(mod, tn);

        present = (status != SES_ESC_NOT_INSTALLED);

        if (topo_mod_nvalloc(mod, &nvl, NV_UNIQUE_NAME) != 0)
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));

        if (nvlist_add_uint32(nvl, TOPO_METH_PRESENT_RET,
            present) != 0) {
                nvlist_free(nvl);
                return (topo_mod_seterrno(mod, EMOD_FMRI_NVL));
        }

        *out = nvl;

        return (0);
}

/*
 * Sets standard properties for a ses node (enclosure, bay, controller
 * or expander).
 * This includes setting the FRU, as well as setting the
 * authority information.  When  the fru topo node(frutn) is not NULL
 * its resouce should be used as FRU.
 */
static int
ses_set_standard_props(topo_mod_t *mod, tnode_t *frutn, tnode_t *tn,
    nvlist_t *auth, uint64_t nodeid, const char *path)
{
        int err;
        char *product, *chassis;
        nvlist_t *fmri;

        /*
         * Set the authority explicitly if specified.
         */
        if (auth) {
                verify(nvlist_lookup_string(auth, FM_FMRI_AUTH_PRODUCT,
                    &product) == 0);
                verify(nvlist_lookup_string(auth, FM_FMRI_AUTH_CHASSIS,
                    &chassis) == 0);
                if (topo_prop_set_string(tn, FM_FMRI_AUTHORITY,
                    FM_FMRI_AUTH_PRODUCT, TOPO_PROP_IMMUTABLE, product,
                    &err) != 0 ||
                    topo_prop_set_string(tn, FM_FMRI_AUTHORITY,
                    FM_FMRI_AUTH_CHASSIS, TOPO_PROP_IMMUTABLE, chassis,
                    &err) != 0 ||
                    topo_prop_set_string(tn, FM_FMRI_AUTHORITY,
                    FM_FMRI_AUTH_SERVER, TOPO_PROP_IMMUTABLE, "",
                    &err) != 0) {
                        topo_mod_dprintf(mod, "failed to add authority "
                            "properties: %s\n", topo_strerror(err));
                        return (topo_mod_seterrno(mod, err));
                }
        }

        /*
         * Copy the resource and set that as the FRU.
         */
        if (frutn != NULL) {
                if (topo_node_resource(frutn, &fmri, &err) != 0) {
                        topo_mod_dprintf(mod,
                            "topo_node_resource() failed : %s\n",
                            topo_strerror(err));
                        return (topo_mod_seterrno(mod, err));
                }
        } else {
                if (topo_node_resource(tn, &fmri, &err) != 0) {
                        topo_mod_dprintf(mod,
                            "topo_node_resource() failed : %s\n",
                            topo_strerror(err));
                        return (topo_mod_seterrno(mod, err));
                }
        }

        if (topo_node_fru_set(tn, fmri, 0, &err) != 0) {
                topo_mod_dprintf(mod,
                    "topo_node_fru_set() failed : %s\n",
                    topo_strerror(err));
                nvlist_free(fmri);
                return (topo_mod_seterrno(mod, err));
        }

        nvlist_free(fmri);

        /*
         * Set the SES-specific properties so that consumers can query
         * additional information about the particular SES element.
         */
        if (topo_pgroup_create(tn, &ses_pgroup, &err) != 0) {
                topo_mod_dprintf(mod, "failed to create propgroup "
                    "%s: %s\n", TOPO_PGROUP_SES, topo_strerror(err));
                return (-1);
        }

        if (topo_prop_set_uint64(tn, TOPO_PGROUP_SES,
            TOPO_PROP_NODE_ID, TOPO_PROP_IMMUTABLE,
            nodeid, &err) != 0) {
                topo_mod_dprintf(mod,
                    "failed to create property %s: %s\n",
                    TOPO_PROP_NODE_ID, topo_strerror(err));
                return (-1);
        }

        if (topo_prop_set_string(tn, TOPO_PGROUP_SES,
            TOPO_PROP_TARGET_PATH, TOPO_PROP_IMMUTABLE,
            path, &err) != 0) {
                topo_mod_dprintf(mod,
                    "failed to create property %s: %s\n",
                    TOPO_PROP_TARGET_PATH, topo_strerror(err));
                return (-1);
        }

        return (0);
}

/*
 * Iterate over the SES phy information. If any of the ports indicates that it's
 * a SATA device and we haven't matched any disk devices yet, that means
 * that the HBA was able to create a WWN for the SATA device based on its GUID,
 * which is good. However, SES includes the WWN for the device's STP bridge. In
 * theory, if the driver includes the WWN based on the SATA guid then it should
 * also set the bridge-port property indicating the WWN that should match the
 * SATA device.
 */
static int
ses_create_disk_bridge(ses_enum_data_t *sdp, tnode_t *pnode, nvlist_t *props,
    tnode_t **child)
{
        nvlist_t **phys;
        uint_t i, n_phys;
        topo_mod_t *mod = sdp->sed_mod;

        if (nvlist_lookup_nvlist_array(props, SES_SAS_PROP_PHYS, &phys,
            &n_phys) != 0)
                return (1);

        for (i = 0; i < n_phys; i++) {
                uint64_t wwn;
                boolean_t sata;
                char wwnstr[64];

                if (nvlist_lookup_uint64(phys[i], SES_SAS_PROP_ADDR,
                    &wwn) != 0 || wwn == 0) {
                        continue;
                }

                if (nvlist_lookup_boolean_value(phys[i],
                    SES_SAS_PROP_SATA_DEVICE, &sata) != 0 || !sata) {
                        continue;
                }

                if (scsi_wwn_to_wwnstr(wwn, 0, wwnstr) == NULL)
                        continue;

                if (disk_declare_bridge(mod, pnode, &sdp->sed_devs,
                    wwnstr, child) == 0) {
                        return (0);
                }

        }

        return (1);
}

/*
 * Callback to add a disk to a given bay.  We first check the status-code to
 * determine if a disk is present, ignoring those that aren't in an appropriate
 * state.  We then scan the parent bay node's SAS address array to determine
 * possible attached SAS addresses.  We create a disk node if the disk is not
 * SAS or the SES target does not support the necessary pages for this; if we
 * find the SAS address, we create a disk node and also correlate it with
 * the corresponding Solaris device node to fill in the rest of the data.
 */
static int
ses_create_disk(ses_enum_data_t *sdp, tnode_t *pnode, nvlist_t *props)
{
        topo_mod_t *mod = sdp->sed_mod;
        uint64_t status;
        uint_t s, nsas;
        char **paths;
        int err, ret;
        tnode_t *child = NULL;

        /*
         * Skip devices that are not in a present (and possibly damaged) state.
         * Also, skip devices that this expander is either not fully wired to,
         * or are hidden due to SAS zoning, as indicated by the
         * SES_ESC_NO_ACCESS state.
         */
        if (nvlist_lookup_uint64(props, SES_PROP_STATUS_CODE, &status) != 0)
                return (0);

        if (status != SES_ESC_UNSUPPORTED &&
            status != SES_ESC_OK &&
            status != SES_ESC_CRITICAL &&
            status != SES_ESC_NONCRITICAL &&
            status != SES_ESC_UNRECOVERABLE &&
            status != SES_ESC_UNKNOWN)
                return (0);

        topo_mod_dprintf(mod, "found attached disk");

        /*
         * Create the disk range.
         */
        if (topo_node_range_create(mod, pnode, DISK, 0, 0) != 0) {
                topo_mod_dprintf(mod,
                    "topo_node_create_range() failed: %s",
                    topo_mod_errmsg(mod));
                return (-1);
        }

        /*
         * Look through all SAS addresses and attempt to correlate them to a
         * known Solaris device.  If we don't find a matching node, then we
         * don't enumerate the disk node.
         * Note that TOPO_PROP_SAS_ADDR prop includes SAS address from
         * alternate elements that represent the same device.
         */
        if (topo_prop_get_string_array(pnode, TOPO_PGROUP_SES,
            TOPO_PROP_SAS_ADDR, &paths, &nsas, &err) != 0)
                return (0);

        err = 0;

        for (s = 0; s < nsas; s++) {
                ret = disk_declare_addr(mod, pnode, &sdp->sed_devs, paths[s],
                    &child);
                if (ret == 0) {
                        break;
                } else if (ret < 0) {
                        err = -1;
                        break;
                }
        }

        /*
         * We need to take another pass through the properties for this bay by
         * iterating over the phys and noting if any of these are SATA. Note,
         * this information isn't commonly part of the topo tree at this time,
         * hence why we end up going back and iterating over the properties
         * ourselves.
         */
        if (s == nsas) {
                if (ses_create_disk_bridge(sdp, pnode, props, &child) != 0)
                        (void) disk_declare_non_enumerated(mod, pnode, &child);
        }

        /* copy sas_addresses (target-ports) from parent (with 'w'added) */
        if (child != NULL) {
                int i;
                char **tports;
                uint64_t wwn;

                tports = topo_mod_zalloc(mod, sizeof (char *) * nsas);
                if (tports != NULL) {
                        for (i = 0; i < nsas; i++) {
                                if (scsi_wwnstr_to_wwn(paths[i], &wwn) !=
                                    DDI_SUCCESS)
                                        break;
                                tports[i] = scsi_wwn_to_wwnstr(wwn, 1, NULL);
                                if (tports[i] == NULL)
                                        break;
                        }
                        /* if they all worked then create the property */
                        if (i == nsas)
                                (void) topo_prop_set_string_array(child,
                                    TOPO_PGROUP_STORAGE,
                                    TOPO_STORAGE_TARGET_PORT_L0IDS,
                                    TOPO_PROP_IMMUTABLE, (const char **)tports,
                                    nsas, &err);

                        for (i = 0; i < nsas; i++)
                                if (tports[i] != NULL)
                                        scsi_free_wwnstr(tports[i]);
                        topo_mod_free(mod, tports, sizeof (char *) * nsas);
                }
        }

        for (s = 0; s < nsas; s++)
                topo_mod_free(mod, paths[s], strlen(paths[s]) + 1);
        topo_mod_free(mod, paths, nsas * sizeof (char *));

        return (err);
}

static int
ses_add_bay_props(topo_mod_t *mod, tnode_t *tn, ses_enum_node_t *snp)
{
        ses_alt_node_t *ap;
        ses_node_t *np;
        nvlist_t *props;

        nvlist_t **phys;
        uint_t i, j, n_phys, all_phys = 0;
        char **paths;
        uint64_t addr;
        size_t len;
        int terr, err = -1;

        for (ap = topo_list_next(&snp->sen_alt_nodes); ap != NULL;
            ap = topo_list_next(ap)) {
                np = ap->san_node;
                props = ses_node_props(np);

                if (nvlist_lookup_nvlist_array(props, SES_SAS_PROP_PHYS,
                    &phys, &n_phys) != 0)
                        continue;

                all_phys += n_phys;
        }

        if (all_phys == 0)
                return (0);

        if ((paths = topo_mod_zalloc(mod, all_phys * sizeof (char *))) == NULL)
                return (-1);

        for (i = 0, ap = topo_list_next(&snp->sen_alt_nodes); ap != NULL;
            ap = topo_list_next(ap)) {
                np = ap->san_node;
                props = ses_node_props(np);

                if (nvlist_lookup_nvlist_array(props, SES_SAS_PROP_PHYS,
                    &phys, &n_phys) != 0)
                        continue;

                for (j = 0; j < n_phys; j++) {
                        if (nvlist_lookup_uint64(phys[j], SES_SAS_PROP_ADDR,
                            &addr) != 0)
                                continue;

                        len = snprintf(NULL, 0, "%016llx", addr) + 1;
                        if ((paths[i] = topo_mod_alloc(mod, len)) == NULL)
                                goto error;

                        (void) snprintf(paths[i], len, "%016llx", addr);

                        ++i;
                }
        }

        err = topo_prop_set_string_array(tn, TOPO_PGROUP_SES,
            TOPO_PROP_SAS_ADDR, TOPO_PROP_IMMUTABLE,
            (const char **)paths, i, &terr);
        if (err != 0)
                err = topo_mod_seterrno(mod, terr);

error:
        for (i = 0; i < all_phys && paths[i] != NULL; i++)
                topo_mod_free(mod, paths[i], strlen(paths[i]) + 1);
        topo_mod_free(mod, paths, all_phys * sizeof (char *));

        return (err);
}

static const char *
lookup_bay_override(const char *product_id)
{
        for (uint_t i = 0; i < N_BAY_LBL_OVERRIDES; i++) {
                if (strcmp(product_id,
                    bay_label_overrides[i].slbl_product) == 0) {
                        return (bay_label_overrides[i].slbl_mname);
                }
        }
        return (NULL);
}

/*
 * Callback to create a basic node (bay, psu, fan, or controller and expander).
 */
static int
ses_create_generic(ses_enum_data_t *sdp, ses_enum_node_t *snp, tnode_t *pnode,
    tnode_t *frutn, const char *nodename, const char *labelname,
    tnode_t **node)
{
        ses_node_t *np = snp->sen_node;
        ses_node_t *parent;
        uint64_t instance = snp->sen_instance;
        topo_mod_t *mod = sdp->sed_mod;
        nvlist_t *props, *aprops;
        nvlist_t *auth = NULL, *fmri = NULL;
        tnode_t *tn = NULL;
        char *clean_label = NULL, label[128];
        int err;
        char *part = NULL, *serial = NULL, *revision = NULL;
        char *desc;
        boolean_t report;

        props = ses_node_props(np);

        (void) nvlist_lookup_string(props, LIBSES_PROP_PART, &part);
        (void) nvlist_lookup_string(props, LIBSES_PROP_SERIAL, &serial);

        topo_mod_dprintf(mod, "adding %s %" PRIu64, nodename, instance);

        /*
         * Create the node.  The interesting information is all copied from the
         * parent enclosure node, so there is not much to do.
         */
        if ((auth = topo_mod_auth(mod, pnode)) == NULL)
                goto error;

        /*
         * We want to report revision information for the controller nodes, but
         * we do not get per-element revision information.  However, we do have
         * revision information for the entire enclosure, and we can use the
         * 'reported-via' property to know that this controller corresponds to
         * the given revision information.  This means we cannot get revision
         * information for targets we are not explicitly connected to, but
         * there is little we can do about the situation.
         */
        if (strcmp(nodename, CONTROLLER) == 0 &&
            nvlist_lookup_boolean_value(props, SES_PROP_REPORT, &report) == 0 &&
            report) {
                for (parent = ses_node_parent(np); parent != NULL;
                    parent = ses_node_parent(parent)) {
                        if (ses_node_type(parent) == SES_NODE_ENCLOSURE) {
                                (void) nvlist_lookup_string(
                                    ses_node_props(parent),
                                    SES_EN_PROP_REV, &revision);
                                break;
                        }
                }
        }

        if ((fmri = topo_mod_hcfmri(mod, pnode, FM_HC_SCHEME_VERSION,
            nodename, (topo_instance_t)instance, NULL, auth, part, revision,
            serial)) == NULL) {
                topo_mod_dprintf(mod, "topo_mod_hcfmri() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        if ((tn = topo_node_bind(mod, pnode, nodename,
            instance, fmri)) == NULL) {
                topo_mod_dprintf(mod, "topo_node_bind() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        /*
         * For the node label, we look for the following in order:
         *
         * <ses-description>
         * <ses-class-description> <instance>
         * <default-type-label> <instance>
         */
        if (nvlist_lookup_string(props, SES_PROP_DESCRIPTION, &desc) != 0 ||
            desc[0] == '\0') {
                parent = ses_node_parent(np);
                aprops = ses_node_props(parent);
                if (nvlist_lookup_string(aprops, SES_PROP_CLASS_DESCRIPTION,
                    &desc) != 0 || desc[0] == '\0')
                        desc = (char *)labelname;
                (void) snprintf(label, sizeof (label), "%s %llu", desc,
                    instance);
                desc = label;
        }

        if ((clean_label = topo_mod_clean_str(mod, desc)) == NULL)
                goto error;

        if (topo_prop_set_string(tn, TOPO_PGROUP_PROTOCOL, TOPO_PROP_LABEL,
            TOPO_PROP_MUTABLE, clean_label, &err) < 0)
                goto error;

        if (ses_set_standard_props(mod, frutn, tn, NULL, ses_node_id(np),
            snp->sen_target->set_devpath) != 0)
                goto error;

        if (strcmp(nodename, BAY) == 0) {
                const char *label_method;
                char *product;
                nvlist_t *args = NULL;

                if (ses_add_bay_props(mod, tn, snp) != 0)
                        goto error;

                if (topo_method_register(mod, tn, ses_bay_methods) != 0) {
                        topo_mod_dprintf(mod,
                            "topo_method_register() failed: %s",
                            topo_mod_errmsg(mod));
                        goto error;
                }

                /*
                 * Ideally we'd perform this sort of override with a platform
                 * specific XML map file, and that would work here if we only
                 * wanted to override the bay node label.  However, we'd also
                 * like the disk node label (if the bay is occupied) to inherit
                 * the overriden bay label.  So we need to ensure the
                 * propmethod is registered before we create the child disk
                 * node.
                 */
                if ((product = topo_mod_product(mod)) == NULL) {
                        (void) topo_mod_seterrno(mod, EMOD_NOMEM);
                        goto error;
                }
                if ((label_method = lookup_bay_override(product)) != NULL) {
                        if (topo_mod_nvalloc(mod, &args, NV_UNIQUE_NAME) != 0 ||
                            topo_prop_method_register(tn, TOPO_PGROUP_PROTOCOL,
                            TOPO_PROP_LABEL, TOPO_TYPE_STRING, label_method,
                            args, &err)) {
                                topo_mod_dprintf(mod,
                                    "Failed to register method: %s on %s=%"
                                    PRIu64, label_method, BAY,
                                    topo_node_instance(tn));
                                topo_mod_strfree(mod, product);
                                nvlist_free(args);
                                goto error;
                        }
                        nvlist_free(args);
                }
                topo_mod_strfree(mod, product);

                if (ses_create_disk(sdp, tn, props) != 0)
                        goto error;
        } else if ((strcmp(nodename, FAN) == 0) ||
            (strcmp(nodename, PSU) == 0) ||
            (strcmp(nodename, CONTROLLER) == 0)) {
                /*
                 * Only fan, psu, and controller nodes have a 'present' method.
                 * Bay nodes are always present, and disk nodes are present by
                 * virtue of being enumerated and SAS expander nodes and
                 * SAS connector nodes are also always present once
                 * the parent controller is found.
                 */
                if (topo_method_register(mod, tn, ses_component_methods) != 0) {
                        topo_mod_dprintf(mod,
                            "topo_method_register() failed: %s",
                            topo_mod_errmsg(mod));
                        goto error;
                }

        }

        snp->sen_target->set_refcount++;
        topo_node_setspecific(tn, snp->sen_target);

        nvlist_free(auth);
        nvlist_free(fmri);
        topo_mod_strfree(mod, clean_label);
        if (node != NULL) *node = tn;
        return (0);

error:
        nvlist_free(auth);
        nvlist_free(fmri);
        topo_mod_strfree(mod, clean_label);
        return (-1);
}

/*
 * Create SAS expander specific props.
 */
/*ARGSUSED*/
static int
ses_set_expander_props(ses_enum_data_t *sdp, ses_enum_node_t *snp,
    tnode_t *ptnode, tnode_t *tnode, int *phycount, int64_t *connlist)
{
        ses_node_t *np = snp->sen_node;
        topo_mod_t *mod = sdp->sed_mod;
        nvlist_t *auth = NULL, *fmri = NULL;
        nvlist_t *props, **phylist;
        int err, i;
        uint_t pcount;
        uint64_t sasaddr, connidx;
        char sasaddr_str[17];
        boolean_t found = B_FALSE, ses_found = B_FALSE;
        dev_di_node_t *dnode, *sesdnode;

        props = ses_node_props(np);

        /*
         * the uninstalled expander is not enumerated by checking
         * the element status code.  No present present' method provided.
         */
        /*
         * Get the Expander SAS address.  It should exist.
         */
        if (nvlist_lookup_uint64(props, SES_EXP_PROP_SAS_ADDR,
            &sasaddr) != 0) {
                topo_mod_dprintf(mod,
                    "Failed to get prop %s.", SES_EXP_PROP_SAS_ADDR);
                goto error;
        }

        (void) sprintf(sasaddr_str, "%llx", sasaddr);

        /* search matching dev_di_node. */
        for (dnode = topo_list_next(&sdp->sed_devs); dnode != NULL;
            dnode = topo_list_next(dnode)) {
                for (i = 0; i < dnode->ddn_ppath_count; i++) {
                        if ((dnode->ddn_target_port[i] != NULL) &&
                            (strstr(dnode->ddn_target_port[i],
                            sasaddr_str) != NULL)) {
                                found = B_TRUE;
                                break;
                        }
                }
                if (found)
                        break;
        }

        if (!found) {
                topo_mod_dprintf(mod,
                    "ses_set_expander_props: Failed to find matching "
                    "devinfo node for Exapnder SAS address %s",
                    SES_EXP_PROP_SAS_ADDR);
                /* continue on to get storage group props. */
        } else {
                /* create/set the devfs-path and devid in the smp group */
                if (topo_pgroup_create(tnode, &smp_pgroup, &err) != 0) {
                        topo_mod_dprintf(mod, "ses_set_expander_props: "
                            "failed to create smp property group %s\n",
                            topo_strerror(err));
                        goto error;
                } else {
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SMP,
                            TOPO_PROP_SMP_TARGET_PORT, TOPO_PROP_IMMUTABLE,
                            dnode->ddn_target_port[i], &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set %s error %s\n", TOPO_PROP_SAS_ADDR,
                                    topo_strerror(err));
                        }
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SMP,
                            TOPO_PROP_SMP_DEV_PATH, TOPO_PROP_IMMUTABLE,
                            dnode->ddn_dpath, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set dev error %s\n", topo_strerror(err));
                        }
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SMP,
                            TOPO_PROP_SMP_DEVID, TOPO_PROP_IMMUTABLE,
                            dnode->ddn_devid, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set devid error %s\n", topo_strerror(err));
                        }
                        if (dnode->ddn_ppath_count != 0 &&
                            topo_prop_set_string_array(tnode, TOPO_PGROUP_SMP,
                            TOPO_PROP_SMP_PHYS_PATH, TOPO_PROP_IMMUTABLE,
                            (const char **)dnode->ddn_ppath,
                            dnode->ddn_ppath_count, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set phys-path error %s\n",
                                    topo_strerror(err));
                        }
                }
        }

        /* update the ses property group with SES target info */
        if ((topo_pgroup_create(tnode, &ses_pgroup, &err) != 0) &&
            (err != ETOPO_PROP_DEFD)) {
                /* SES prop group doesn't exist but failed to be created. */
                topo_mod_dprintf(mod, "ses_set_expander_props: "
                    "ses pgroup create error %s\n", topo_strerror(err));
                goto error;
        } else {
                /* locate assciated enclosure dev_di_node. */
                for (sesdnode = topo_list_next(&sdp->sed_devs);
                    sesdnode != NULL; sesdnode = topo_list_next(sesdnode)) {
                        for (i = 0; i < sesdnode->ddn_ppath_count; i++) {
                                /*
                                 * check if attached port exists and
                                 * its node type is enclosure and
                                 * attached port is same as sas address of
                                 * the expander and
                                 * bridge port for virtual phy indication
                                 * exist.
                                 */
                                if ((sesdnode->ddn_attached_port[i] != NULL) &&
                                    (sesdnode->ddn_dtype == DTYPE_ESI) &&
                                    (strstr(sesdnode->ddn_attached_port[i],
                                    sasaddr_str) != NULL) &&
                                    (sesdnode->ddn_bridge_port[i] != NULL)) {
                                        ses_found = B_TRUE;
                                        break;
                                }
                        }
                        if (ses_found) break;
                }

                if (ses_found) {
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SES,
                            TOPO_PROP_SES_TARGET_PORT, TOPO_PROP_IMMUTABLE,
                            sesdnode->ddn_target_port[i], &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set ses %s error %s\n", TOPO_PROP_SAS_ADDR,
                                    topo_strerror(err));
                        }
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SES,
                            TOPO_PROP_SES_DEV_PATH, TOPO_PROP_IMMUTABLE,
                            sesdnode->ddn_dpath, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set ses dev error %s\n",
                                    topo_strerror(err));
                        }
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_SES,
                            TOPO_PROP_SES_DEVID, TOPO_PROP_IMMUTABLE,
                            sesdnode->ddn_devid, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set ses devid error %s\n",
                                    topo_strerror(err));
                        }
                        if (sesdnode->ddn_ppath_count != 0 &&
                            topo_prop_set_string_array(tnode, TOPO_PGROUP_SES,
                            TOPO_PROP_SES_PHYS_PATH, TOPO_PROP_IMMUTABLE,
                            (const char **)sesdnode->ddn_ppath,
                            sesdnode->ddn_ppath_count, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set ses phys-path error %s\n",
                                    topo_strerror(err));
                        }

                }
        }

        /* create the storage group */
        if (topo_pgroup_create(tnode, &storage_pgroup, &err) != 0) {
                topo_mod_dprintf(mod, "ses_set_expander_props: "
                    "create storage error %s\n", topo_strerror(err));
                goto error;
        } else {
                /* set the SAS address prop out of expander element status. */
                if (topo_prop_set_string(tnode, TOPO_PGROUP_STORAGE,
                    TOPO_PROP_SAS_ADDR, TOPO_PROP_IMMUTABLE, sasaddr_str,
                    &err) != 0) {
                        topo_mod_dprintf(mod, "ses_set_expander_props: "
                            "set %s error %s\n", TOPO_PROP_SAS_ADDR,
                            topo_strerror(err));
                }

                /* Get the phy information for the expander */
                if (nvlist_lookup_nvlist_array(props, SES_SAS_PROP_PHYS,
                    &phylist, &pcount) != 0) {
                        topo_mod_dprintf(mod,
                            "Failed to get prop %s.", SES_SAS_PROP_PHYS);
                } else {
                        /*
                         * For each phy, get the connector element index and
                         * stores into connector element index array.
                         */
                        *phycount = pcount;
                        for (i = 0; i < pcount; i++) {
                                if (nvlist_lookup_uint64(phylist[i],
                                    SES_PROP_CE_IDX, &connidx) == 0) {
                                        if (connidx != 0xff) {
                                                connlist[i] = connidx;
                                        } else {
                                                connlist[i] = -1;
                                        }
                                } else {
                                        /* Fail to get the index. set to -1. */
                                        connlist[i] = -1;
                                }
                        }

                        /* set the phy count prop of the expander. */
                        if (topo_prop_set_uint64(tnode, TOPO_PGROUP_STORAGE,
                            TOPO_PROP_PHY_COUNT, TOPO_PROP_IMMUTABLE, pcount,
                            &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set %s error %s\n", TOPO_PROP_PHY_COUNT,
                                    topo_strerror(err));
                        }

                        /*
                         * set the connector element index of
                         * the expander phys.
                         */
                }

                /* populate other misc storage group properties */
                if (found) {
                        if (dnode->ddn_mfg && (topo_prop_set_string(tnode,
                            TOPO_PGROUP_STORAGE, TOPO_STORAGE_MANUFACTURER,
                            TOPO_PROP_IMMUTABLE, dnode->ddn_mfg, &err) != 0)) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set mfg error %s\n", topo_strerror(err));
                        }

                        if (dnode->ddn_model && (topo_prop_set_string(tnode,
                            TOPO_PGROUP_STORAGE, TOPO_STORAGE_MODEL,
                            TOPO_PROP_IMMUTABLE,
                            dnode->ddn_model, &err) != 0)) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set model error %s\n", topo_strerror(err));
                        }

                        if (dnode->ddn_serial && (topo_prop_set_string(tnode,
                            TOPO_PGROUP_STORAGE, TOPO_STORAGE_SERIAL_NUM,
                            TOPO_PROP_IMMUTABLE,
                            dnode->ddn_serial, &err) != 0)) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set serial error %s\n",
                                    topo_strerror(err));
                        }

                        if (dnode->ddn_firm && (topo_prop_set_string(tnode,
                            TOPO_PGROUP_STORAGE,
                            TOPO_STORAGE_FIRMWARE_REV, TOPO_PROP_IMMUTABLE,
                            dnode->ddn_firm, &err) != 0)) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set firm error %s\n", topo_strerror(err));
                        }
                }
        }

        return (0);

error:
        nvlist_free(auth);
        nvlist_free(fmri);
        return (-1);
}

/*
 * Create SAS expander specific props.
 */
/*ARGSUSED*/
static int
ses_set_connector_props(ses_enum_data_t *sdp, ses_enum_node_t *snp,
    tnode_t *tnode, int64_t phy_mask)
{
        ses_node_t *np = snp->sen_node;
        topo_mod_t *mod = sdp->sed_mod;
        nvlist_t *props;
        int err, i;
        uint64_t conntype;
        char phymask_str[17], *conntype_str;
        boolean_t   found;

        props = ses_node_props(np);

        /*
         * convert phy mask to string.
         */
        (void) snprintf(phymask_str, 17, "%llx", phy_mask);

        /* create the storage group */
        if (topo_pgroup_create(tnode, &storage_pgroup, &err) != 0) {
                topo_mod_dprintf(mod, "ses_set_expander_props: "
                    "create storage error %s\n", topo_strerror(err));
                return (-1);
        } else {
                /* set the SAS address prop of the expander. */
                if (topo_prop_set_string(tnode, TOPO_PGROUP_STORAGE,
                    TOPO_STORAGE_SAS_PHY_MASK, TOPO_PROP_IMMUTABLE,
                    phymask_str, &err) != 0) {
                        topo_mod_dprintf(mod, "ses_set_expander_props: "
                            "set %s error %s\n", TOPO_STORAGE_SAS_PHY_MASK,
                            topo_strerror(err));
                }

                /* Get the connector type information for the expander */
                if (nvlist_lookup_uint64(props,
                    SES_SC_PROP_CONNECTOR_TYPE, &conntype) != 0) {
                        topo_mod_dprintf(mod, "Failed to get prop %s.",
                            TOPO_STORAGE_SAS_PHY_MASK);
                } else {
                        found = B_FALSE;
                        for (i = 0; ; i++) {
                                if (sas_connector_type_list[i].sct_type ==
                                    SAS_CONNECTOR_TYPE_CODE_NOT_DEFINED) {
                                        break;
                                }
                                if (sas_connector_type_list[i].sct_type ==
                                    conntype) {
                                        conntype_str =
                                            sas_connector_type_list[i].sct_name;
                                        found = B_TRUE;
                                        break;
                                }
                        }

                        if (!found) {
                                if (conntype <
                                    SAS_CONNECTOR_TYPE_CODE_NOT_DEFINED) {
                                        conntype_str =
                                            SAS_CONNECTOR_TYPE_RESERVED;
                                } else {
                                        conntype_str =
                                            SAS_CONNECTOR_TYPE_NOT_DEFINED;
                                }
                        }

                        /* set the phy count prop of the expander. */
                        if (topo_prop_set_string(tnode, TOPO_PGROUP_STORAGE,
                            TOPO_STORAGE_SAS_CONNECTOR_TYPE,
                            TOPO_PROP_IMMUTABLE, conntype_str, &err) != 0) {
                                topo_mod_dprintf(mod, "ses_set_expander_props: "
                                    "set %s error %s\n", TOPO_PROP_PHY_COUNT,
                                    topo_strerror(err));
                        }
                }
        }

        return (0);
}

/*
 * Instantiate SAS expander nodes for a given ESC Electronics node(controller)
 * nodes.
 */
/*ARGSUSED*/
static int
ses_create_esc_sasspecific(ses_enum_data_t *sdp, ses_enum_node_t *snp,
    tnode_t *pnode, ses_enum_chassis_t *cp,
    boolean_t dorange)
{
        topo_mod_t *mod = sdp->sed_mod;
        tnode_t *exptn, *contn;
        boolean_t found;
        sas_connector_phy_data_t connectors[64] = {0};
        uint64_t max;
        ses_enum_node_t *ctlsnp, *xsnp, *consnp;
        ses_node_t *np = snp->sen_node;
        nvlist_t *props, *psprops;
        uint64_t index, psindex, conindex, psstatus, i, j, count;
        int64_t cidxlist[256] = {0};
        int phycount;

        props = ses_node_props(np);

        if (nvlist_lookup_uint64(props, SES_PROP_ELEMENT_ONLY_INDEX,
            &index) != 0)
                return (-1);

        /*
         * For SES constroller node, check to see if there are
         * associated SAS expanders.
         */
        found = B_FALSE;
        max = 0;
        for (ctlsnp = topo_list_next(&cp->sec_nodes); ctlsnp != NULL;
            ctlsnp = topo_list_next(ctlsnp)) {
                if (ctlsnp->sen_type == SES_ET_SAS_EXPANDER) {
                        found = B_TRUE;
                        if (ctlsnp->sen_instance > max)
                                max = ctlsnp->sen_instance;
                }
        }

        /*
         * No SAS expander found notthing to process.
         */
        if (!found)
                return (0);

        topo_mod_dprintf(mod, "%s Controller %" PRIu64 ": creating "
            "%" PRIu64 " %s nodes", cp->sec_csn, index, max + 1, SASEXPANDER);

        /*
         * The max number represent the number of elements
         * deducted from the highest SES_PROP_ELEMENT_CLASS_INDEX
         * of SET_ET_SAS_EXPANDER type element.
         *
         * There may be multiple ESC Electronics element(controllers)
         * within JBOD(typicall two for redundancy) and SAS expander
         * elements are associated with only one of them.  We are
         * still creating the range based max number here.
         * That will cover the case that all expanders are associated
         * with one SES controller.
         */
        if (dorange && topo_node_range_create(mod, pnode,
            SASEXPANDER, 0, max) != 0) {
                topo_mod_dprintf(mod,
                    "topo_node_create_range() failed: %s",
                    topo_mod_errmsg(mod));
                return (-1);
        }

        /*
         * Search exapnders with the parent index matching with
         * ESC Electronics element index.
         * Note the index used here is a global index across
         * SES elements.
         */
        for (xsnp = topo_list_next(&cp->sec_nodes); xsnp != NULL;
            xsnp = topo_list_next(xsnp)) {
                if (xsnp->sen_type == SES_ET_SAS_EXPANDER) {
                        /*
                         * get the parent ESC controller.
                         */
                        psprops = ses_node_props(xsnp->sen_node);
                        if (nvlist_lookup_uint64(psprops,
                            SES_PROP_STATUS_CODE, &psstatus) == 0) {
                                if (psstatus == SES_ESC_NOT_INSTALLED) {
                                        /*
                                         * Not installed.
                                         * Don't create a ndoe.
                                         */
                                        continue;
                                }
                        } else {
                                /*
                                 * The element should have status code.
                                 * If not there is no way to find
                                 * out if the expander element exist or
                                 * not.
                                 */
                                continue;
                        }

                        /* Get the physical parent index to compare. */
                        if (nvlist_lookup_uint64(psprops,
                            LIBSES_PROP_PHYS_PARENT, &psindex) == 0) {
                                if (index == psindex) {
                /* indentation moved forward */
                /*
                 * Handle basic node information of SAS expander
                 * element - binding to parent node and
                 * allocating FMRI...
                 */
                if (ses_create_generic(sdp, xsnp, pnode, pnode, SASEXPANDER,
                    "SAS-EXPANDER", &exptn) != 0)
                        continue;
                /*
                 * Now handle SAS expander unique portion of node creation.
                 * The max nubmer of the phy count is 256 since SES-2
                 * defines as 1 byte field.  The cidxlist has the same
                 * number of elements.
                 *
                 * We use size 64 array to store the connectors.
                 * Typically a connectors associated with 4 phys so that
                 * matches with the max number of connecters associated
                 * with an expander.
                 * The phy count goes up to 38 for Sun supported
                 * JBOD.
                 */
                (void) memset(cidxlist, 0, sizeof (int64_t) * 64);
                if (ses_set_expander_props(sdp, xsnp, pnode, exptn, &phycount,
                    cidxlist) != 0) {
                        /*
                         * error on getting specific prop failed.
                         * continue on.  Note that the node is
                         * left bound.
                         */
                        continue;
                }

                /*
                 * count represetns the number of connectors discovered so far.
                 */
                count = 0;
                (void) memset(connectors, 0,
                    sizeof (sas_connector_phy_data_t) * 64);
                for (i = 0; i < phycount; i++) {
                        if (cidxlist[i] != -1) {
                                /* connector index is valid. */
                                for (j = 0; j < count; j++) {
                                        if (connectors[j].scpd_index ==
                                            cidxlist[i]) {
                                                /*
                                                 * Just update phy mask.
                                                 * The postion for connector
                                                 * index lists(cidxlist index)
                                                 * is set.
                                                 */
                                                connectors[j].scpd_pm =
                                                    connectors[j].scpd_pm |
                                                    (1ULL << i);
                                                break;
                                        }
                                }
                                /*
                                 * If j and count matche a  new connector
                                 * index is found.
                                 */
                                if (j == count) {
                                        /* add a new index and phy mask. */
                                        connectors[count].scpd_index =
                                            cidxlist[i];
                                        connectors[count].scpd_pm =
                                            connectors[count].scpd_pm |
                                            (1ULL << i);
                                        count++;
                                }
                        }
                }

                /*
                 * create range for the connector nodes.
                 * The class index of the ses connector element
                 * is set as the instance nubmer for the node.
                 * Even though one expander may not have all connectors
                 * are associated with we are creating the range with
                 * max possible instance number.
                 */
                found = B_FALSE;
                max = 0;
                for (consnp = topo_list_next(&cp->sec_nodes);
                    consnp != NULL; consnp = topo_list_next(consnp)) {
                        if (consnp->sen_type == SES_ET_SAS_CONNECTOR) {
                                psprops = ses_node_props(consnp->sen_node);
                                found = B_TRUE;
                                if (consnp->sen_instance > max)
                                        max = consnp->sen_instance;
                        }
                }

                /*
                 * No SAS connector found nothing to process.
                 */
                if (!found)
                        return (0);

                if (dorange && topo_node_range_create(mod, exptn,
                    RECEPTACLE, 0, max) != 0) {
                        topo_mod_dprintf(mod,
                            "topo_node_create_range() failed: %s",
                            topo_mod_errmsg(mod));
                        return (-1);
                }

                /* search matching connector element using the index. */
                for (i = 0; i < count; i++) {
                        found = B_FALSE;
                        for (consnp = topo_list_next(&cp->sec_nodes);
                            consnp != NULL; consnp = topo_list_next(consnp)) {
                                if (consnp->sen_type == SES_ET_SAS_CONNECTOR) {
                                        psprops = ses_node_props(
                                            consnp->sen_node);
                                        /*
                                         * Get the physical parent index to
                                         * compare.
                                         * The connector elements are children
                                         * of ESC Electronics element even
                                         * though we enumerate them under
                                         * an expander in libtopo.
                                         */
                                        if (nvlist_lookup_uint64(psprops,
                                            SES_PROP_ELEMENT_ONLY_INDEX,
                                            &conindex) == 0) {
                                                if (conindex ==
                                                    connectors[i].scpd_index) {
                                                        found = B_TRUE;
                                                        break;
                                                }
                                        }
                                }
                        }

                        /* now create a libtopo node. */
                        if (found) {
                                /* Create generic props. */
                                if (ses_create_generic(sdp, consnp, exptn,
                                    topo_node_parent(exptn),
                                    RECEPTACLE, "RECEPTACLE", &contn) !=
                                    0) {
                                        continue;
                                }
                                /* Create connector specific props. */
                                if (ses_set_connector_props(sdp, consnp,
                                    contn, connectors[i].scpd_pm) != 0) {
                                        continue;
                                }
                                if (topo_method_register(mod, contn,
                                    ses_recep_methods) != 0) {
                                        topo_mod_dprintf(mod,
                                            "topo_method_register() failed: "
                                            "%s",
                                            topo_mod_errmsg(mod));
                                        continue;
                                }

                        }
                }
                /* end indentation change */
                                }
                        }
                }
        }

        return (0);
}

/*
 * Instantiate any protocol specific portion of a node.
 */
/*ARGSUSED*/
static int
ses_create_protocol_specific(ses_enum_data_t *sdp, ses_enum_node_t *snp,
    tnode_t *pnode, uint64_t type, ses_enum_chassis_t *cp,
    boolean_t dorange)
{

        if (type == SES_ET_ESC_ELECTRONICS) {
                /* create SAS specific children(expanders and connectors. */
                return (ses_create_esc_sasspecific(sdp, snp, pnode, cp,
                    dorange));
        }

        return (0);
}

/*
 * Instantiate any children of a given type.
 */
static int
ses_create_children(ses_enum_data_t *sdp, tnode_t *pnode, uint64_t type,
    const char *nodename, const char *defaultlabel, ses_enum_chassis_t *cp,
    boolean_t dorange)
{
        topo_mod_t *mod = sdp->sed_mod;
        boolean_t found;
        uint64_t max;
        ses_enum_node_t *snp;
        tnode_t *tn;

        /*
         * First go through and count how many matching nodes we have.
         */
        max = 0;
        found = B_FALSE;
        for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
            snp = topo_list_next(snp)) {
                if (snp->sen_type == type) {
                        found = B_TRUE;
                        if (snp->sen_instance > max)
                                max = snp->sen_instance;
                }
        }

        /*
         * No enclosure should export both DEVICE and ARRAY_DEVICE elements.
         * Since we map both of these to 'disk', if an enclosure does this, we
         * just ignore the array elements.
         */
        if (!found ||
            (type == SES_ET_ARRAY_DEVICE && cp->sec_hasdev))
                return (0);

        topo_mod_dprintf(mod, "%s: creating %" PRIu64 " %s nodes",
            cp->sec_csn, max + 1, nodename);

        if (dorange && topo_node_range_create(mod, pnode,
            nodename, 0, max) != 0) {
                topo_mod_dprintf(mod,
                    "topo_node_create_range() failed: %s",
                    topo_mod_errmsg(mod));
                return (-1);
        }

        for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
            snp = topo_list_next(snp)) {
                if (snp->sen_type == type) {
                        /*
                         * With flat layout of ses nodes there is no
                         * way to find out the direct FRU for a node.
                         * Passing NULL for fru topo node.  Note that
                         * ses_create_children_from_phys_tree() provides
                         * the actual direct FRU for a node.
                         */
                        if (ses_create_generic(sdp, snp, pnode, NULL,
                            nodename, defaultlabel, &tn) != 0)
                                return (-1);
                        /*
                         * For some SES element there may be protocol specific
                         * information to process.   Here we are processing
                         * the association between enclosure controller and
                         * SAS expanders.
                         */
                        if (type == SES_ET_ESC_ELECTRONICS) {
                                /* create SAS expander node */
                                if (ses_create_protocol_specific(sdp, snp,
                                    tn, type, cp, dorange) != 0) {
                                        return (-1);
                                }
                        }

                }
        }

        return (0);
}

/*
 * Instantiate a new subchassis instance in the topology.
 */
static int
ses_create_subchassis(ses_enum_data_t *sdp, tnode_t *pnode,
    ses_enum_chassis_t *scp)
{
        topo_mod_t *mod = sdp->sed_mod;
        tnode_t *tn;
        nvlist_t *props;
        nvlist_t *auth = NULL, *fmri = NULL;
        uint64_t instance = scp->sec_instance;
        char *desc;
        char *clean_label = NULL, label[128];
        char **paths;
        int i, err;
        ses_enum_target_t *stp;
        int ret = -1;

        /*
         * Copy authority information from parent enclosure node
         */
        if ((auth = topo_mod_auth(mod, pnode)) == NULL)
                goto error;

        /*
         * Record the subchassis serial number in the FMRI.
         * For now, we assume that logical id is the subchassis serial number.
         * If this assumption changes in future, then the following
         * piece of code will need to be updated via an RFE.
         */
        if ((fmri = topo_mod_hcfmri(mod, pnode, FM_HC_SCHEME_VERSION,
            SUBCHASSIS, (topo_instance_t)instance, NULL, auth, NULL, NULL,
            NULL)) == NULL) {
                topo_mod_dprintf(mod, "topo_mod_hcfmri() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        if ((tn = topo_node_bind(mod, pnode, SUBCHASSIS,
            instance, fmri)) == NULL) {
                topo_mod_dprintf(mod, "topo_node_bind() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        props = ses_node_props(scp->sec_enclosure);

        /*
         * Look for the subchassis label in the following order:
         *      <ses-description>
         *      <ses-class-description> <instance>
         *      <default-type-label> <instance>
         *
         * For subchassis, the default label is "SUBCHASSIS"
         */
        if (nvlist_lookup_string(props, SES_PROP_DESCRIPTION, &desc) != 0 ||
            desc[0] == '\0') {
                if (nvlist_lookup_string(props, SES_PROP_CLASS_DESCRIPTION,
                    &desc) == 0 && desc[0] != '\0')
                        (void) snprintf(label, sizeof (label), "%s %llu", desc,
                            instance);
                else
                        (void) snprintf(label, sizeof (label),
                            "SUBCHASSIS %llu", instance);
                desc = label;
        }

        if ((clean_label = topo_mod_clean_str(mod, desc)) == NULL)
                goto error;

        if (topo_prop_set_string(tn, TOPO_PGROUP_PROTOCOL, TOPO_PROP_LABEL,
            TOPO_PROP_MUTABLE, clean_label, &err) < 0)
                goto error;

        if (ses_set_standard_props(mod, NULL, tn, NULL,
            ses_node_id(scp->sec_enclosure), scp->sec_target->set_devpath) != 0)
                goto error;

        /*
         * Set the 'chassis-type' property for this subchassis.  This is either
         * 'ses-class-description' or 'subchassis'.
         */
        if (nvlist_lookup_string(props, SES_PROP_CLASS_DESCRIPTION, &desc) != 0)
                desc = "subchassis";

        if (topo_prop_set_string(tn, TOPO_PGROUP_SES,
            TOPO_PROP_CHASSIS_TYPE, TOPO_PROP_IMMUTABLE, desc, &err) != 0) {
                topo_mod_dprintf(mod, "failed to create property %s: %s\n",
                    TOPO_PROP_CHASSIS_TYPE, topo_strerror(err));
                goto error;
        }

        /*
         * For enclosures, we want to include all possible targets (for upgrade
         * purposes).
         */
        for (i = 0, stp = topo_list_next(&scp->sec_targets); stp != NULL;
            stp = topo_list_next(stp), i++)
                ;

        verify(i != 0);
        paths = alloca(i * sizeof (char *));

        for (i = 0, stp = topo_list_next(&scp->sec_targets); stp != NULL;
            stp = topo_list_next(stp), i++)
                paths[i] = stp->set_devpath;

        if (topo_prop_set_string_array(tn, TOPO_PGROUP_SES,
            TOPO_PROP_PATHS, TOPO_PROP_IMMUTABLE, (const char **)paths,
            i, &err) != 0) {
                topo_mod_dprintf(mod, "failed to create property %s: %s\n",
                    TOPO_PROP_PATHS, topo_strerror(err));
                goto error;
        }

        if (topo_method_register(mod, tn, ses_enclosure_methods) != 0) {
                topo_mod_dprintf(mod, "topo_method_register() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        /*
         * Create the nodes for controllers and bays.
         */
        if (ses_create_children(sdp, tn, SES_ET_ESC_ELECTRONICS,
            CONTROLLER, "CONTROLLER", scp, B_TRUE) != 0 ||
            ses_create_children(sdp, tn, SES_ET_DEVICE,
            BAY, "BAY", scp, B_TRUE) != 0 ||
            ses_create_children(sdp, tn, SES_ET_ARRAY_DEVICE,
            BAY, "BAY", scp, B_TRUE) != 0)
                goto error;

        ret = 0;

error:
        nvlist_free(auth);
        nvlist_free(fmri);
        topo_mod_strfree(mod, clean_label);
        return (ret);
}

/*
 * Function we use to insert a node.
 */
static int
ses_phys_tree_insert(topo_mod_t *mod, ses_phys_tree_t **sproot,
    ses_phys_tree_t *child)
{
        uint64_t ppindex, eindex, pindex;
        ses_phys_tree_t *node_ptr;
        int ret = 0;

        assert(sproot != NULL);
        assert(child != NULL);

        if (*sproot == NULL) {
                *sproot = child;
                return (0);
        }

        pindex = child->spt_pindex;
        ppindex = (*sproot)->spt_pindex;
        eindex = (*sproot)->spt_eonlyindex;

        /*
         * If the element only index of the root is same as the physical
         * parent index of a node to be added, add the node as a child of
         * the current root.
         */
        if (eindex == pindex) {
                (void) ses_phys_tree_insert(mod, &(*sproot)->spt_child, child);
                child->spt_parent = *sproot;
        } else if (ppindex == pindex) {
                /*
                 * if the physical parent of the current root and the child
                 * is same, then this should be a sibling node.
                 * Siblings can be different element types and arrange
                 * them by group.
                 */
                if ((*sproot)->spt_senumnode->sen_type ==
                    child->spt_senumnode->sen_type) {
                        child->spt_sibling = *sproot;
                        *sproot = child;
                } else {
                        /* add a node in front of matching element type. */
                        node_ptr = *sproot;
                        while (node_ptr->spt_sibling != NULL) {
                                if (node_ptr->spt_sibling->
                                    spt_senumnode->sen_type ==
                                    child->spt_senumnode->sen_type) {
                                        child->spt_sibling =
                                            node_ptr->spt_sibling;
                                        node_ptr->spt_sibling = child;
                                        break;
                                }
                                node_ptr = node_ptr->spt_sibling;
                        }
                        /* no matching.  Add the child at the end. */
                        if (node_ptr->spt_sibling == NULL) {
                                node_ptr->spt_sibling = child;
                        }
                }
                child->spt_parent = (*sproot)->spt_parent;
        } else {
                /*
                 * The root and the node is not directly related.
                 * Try to insert to the child sub-tree first and then try to
                 * insert to the sibling sub-trees.  If fails for both
                 * the caller will retry insertion later.
                 */
                if ((*sproot)->spt_child) {
                        ret = ses_phys_tree_insert(mod, &(*sproot)->spt_child,
                            child);
                }
                if ((*sproot)->spt_child == NULL || ret != 0) {
                        if ((*sproot)->spt_sibling) {
                                ret = ses_phys_tree_insert(mod,
                                    &(*sproot)->spt_sibling, child);
                        } else {
                                ret = 1;
                        }
                }
                return (ret);
        }
        return (0);
}

/*
 * Construct tree view of ses elements through parent phyiscal element index.
 * The root of tree is already constructed using the enclosure element.
 */
static int
ses_construct_phys_tree(ses_enum_data_t *sdp, ses_enum_chassis_t *cp,
    ses_phys_tree_t *sproot)
{
        ses_enum_node_t *snp;
        ses_phys_tree_t *child;
        ses_phys_tree_t *u_watch = NULL;
        ses_phys_tree_t *u_head = NULL;
        ses_phys_tree_t *u_tail = NULL;
        int u_inserted = 0, u_left = 0;
        nvlist_t *props;
        topo_mod_t *mod = sdp->sed_mod;

        for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
            snp = topo_list_next(snp)) {
                if ((child = topo_mod_zalloc(mod,
                    sizeof (ses_phys_tree_t))) == NULL) {
                        topo_mod_dprintf(mod,
                            "failed to allocate root.");
                        return (-1);
                }
                child->spt_snode = snp->sen_node;
                props = ses_node_props(snp->sen_node);
                if (nvlist_lookup_uint64(props,
                    LIBSES_PROP_PHYS_PARENT, &child->spt_pindex) != 0) {
                        /*
                         * the prop should exist. continue to see if
                         * we can build a partial tree with other elements.
                         */
                        topo_mod_dprintf(mod,
                            "ses_construct_phys_tree(): Failed to find prop %s "
                            "on ses element type %" PRIu64 " and instance %"
                            PRIu64 " (CSN %s).", LIBSES_PROP_PHYS_PARENT,
                            snp->sen_type, snp->sen_instance, cp->sec_csn);
                        topo_mod_free(mod, child, sizeof (ses_phys_tree_t));
                        continue;
                } else {
                        if (nvlist_lookup_boolean_value(props,
                            LIBSES_PROP_FRU, &child->spt_isfru) != 0) {
                                topo_mod_dprintf(mod,
                                    "ses_construct_phys_tree(): Failed to "
                                    "find prop %s on ses element type %" PRIu64
                                    " and instance %" PRIu64 " (CSN %s).",
                                    LIBSES_PROP_FRU,
                                    snp->sen_type, snp->sen_instance,
                                    cp->sec_csn);
                                /*
                                 * Ignore if the prop doesn't exist.
                                 * Note that the enclosure itself should be
                                 * a FRU so if no FRU found the enclosure FRU
                                 * can be a direct FRU.
                                 */
                        }
                        verify(nvlist_lookup_uint64(props,
                            SES_PROP_ELEMENT_ONLY_INDEX,
                            &child->spt_eonlyindex) == 0);
                        verify(nvlist_lookup_uint64(props,
                            SES_PROP_ELEMENT_CLASS_INDEX,
                            &child->spt_cindex) == 0);
                }
                child->spt_senumnode = snp;
                if (ses_phys_tree_insert(mod, &sproot, child) != 0) {
                        /* collect unresolved element to process later. */
                        if (u_head == NULL) {
                                u_head = child;
                                u_tail = child;
                        } else {
                                child->spt_sibling = u_head;
                                u_head = child;
                        }
                }
        }

        /*
         * The parent of a child node may not be inserted yet.
         * Trying to insert the child until no child is left or
         * no child is not added further.  For the latter
         * the hierarchical relationship between elements
         * should be checked through SUNW,FRUID page.
         * u_watch is a watch dog to check the prgress of unresolved
         * node.
         */
        u_watch = u_tail;
        while (u_head) {
                child = u_head;
                u_head = u_head->spt_sibling;
                if (u_head == NULL)
                        u_tail = NULL;
                child->spt_sibling = NULL;
                if (ses_phys_tree_insert(mod, &sproot, child) != 0) {
                        u_tail->spt_sibling = child;
                        u_tail = child;
                        if (child == u_watch) {
                                /*
                                 * We just scanned one round for the
                                 * unresolved list. Check to see whether we
                                 * have nodes inserted, if none, we should
                                 * break in case of an indefinite loop.
                                 */
                                if (u_inserted == 0) {
                                        /*
                                         * Indicate there is unhandled node.
                                         * Chain free the whole unsolved
                                         * list here.
                                         */
                                        u_left++;
                                        break;
                                } else {
                                        u_inserted = 0;
                                        u_watch = u_tail;
                                }
                        }
                } else {
                        /*
                         * We just inserted one rpnode, increment the
                         * unsolved_inserted counter. We will utilize this
                         * counter to detect an indefinite insertion loop.
                         */
                        u_inserted++;
                        if (child == u_watch) {
                                /*
                                 * watch dog node itself is inserted.
                                 * Set it to the tail and refresh the watching.
                                 */
                                u_watch = u_tail;
                                u_inserted = 0;
                                u_left = 0;
                        }
                }
        }

        /* check if there is left out unresolved nodes. */
        if (u_left) {
                topo_mod_dprintf(mod, "ses_construct_phys_tree(): "
                    "Failed to construct physical view of the following "
                    "ses elements of Chassis CSN %s.", cp->sec_csn);
                while (u_head) {
                        u_tail = u_head->spt_sibling;
                        topo_mod_dprintf(mod,
                            "\telement type (%" PRIu64 ") and instance (%"
                            PRIu64 ")", u_head->spt_senumnode->sen_type,
                            u_head->spt_senumnode->sen_instance);
                        topo_mod_free(mod, u_head, sizeof (ses_phys_tree_t));
                        u_head = u_tail;
                }
                return (-1);
        }

        return (0);
}

/*
 * Free the whole phys tree.
 */
static void ses_phys_tree_free(topo_mod_t *mod, ses_phys_tree_t *sproot)
{
        if (sproot == NULL)
                return;

        /* Free child tree. */
        if (sproot->spt_child) {
                ses_phys_tree_free(mod, sproot->spt_child);
        }

        /* Free sibling trees. */
        if (sproot->spt_sibling) {
                ses_phys_tree_free(mod, sproot->spt_sibling);
        }

        /* Free root node itself. */
        topo_mod_free(mod, sproot, sizeof (ses_phys_tree_t));
}

/*
 * Parses phys_enum_type table to get the index of the given type.
 */
static boolean_t
is_type_enumerated(ses_phys_tree_t *node, int *index)
{
        int i;

        for (i = 0; i < N_PHYS_ENUM_TYPES; i++) {
                if (node->spt_senumnode->sen_type ==
                    phys_enum_type_list[i].pet_type) {
                        *index = i;
                        return (B_TRUE);
                }
        }
        return (B_FALSE);
}

/*
 * Recusrive routine for top-down enumeration of the tree.
 */
static int
ses_enumerate_node(ses_enum_data_t *sdp, tnode_t *pnode, ses_enum_chassis_t *cp,
    ses_phys_tree_t *parent, int mrange[])
{
        topo_mod_t *mod = sdp->sed_mod;
        ses_phys_tree_t *child = NULL;
        int i, ret = 0, ret_ch;
        uint64_t prevtype = SES_ET_UNSPECIFIED;
        ses_phys_tree_t *dirfru = NULL;
        tnode_t *tn = NULL, *frutn = NULL;

        if (parent == NULL) {
                return (0);
        }

        for (child = parent->spt_child; child != NULL;
            child = child->spt_sibling) {
                if (is_type_enumerated(child, &i)) {
                        if (prevtype != phys_enum_type_list[i].pet_type) {
                                /* check if range needs to be created. */
                                if (phys_enum_type_list[i].pet_dorange &&
                                    topo_node_range_create(mod, pnode,
                                    phys_enum_type_list[i].pet_nodename, 0,
                                    mrange[i]) != 0) {
                                        topo_mod_dprintf(mod,
                                            "topo_node_create_range() failed: "
                                            "%s", topo_mod_errmsg(mod));
                                        return (-1);
                                }
                                prevtype = phys_enum_type_list[i].pet_type;
                        }

                        if (!(child->spt_isfru)) {
                                for (dirfru = parent; dirfru != NULL;
                                    dirfru = dirfru->spt_parent) {
                                        if (dirfru->spt_isfru) {
                                                break;
                                        }
                                }
                                /* found direct FRU node. */
                                if (dirfru) {
                                        frutn = dirfru->spt_tnode;
                                } else {
                                        frutn = NULL;
                                }
                        } else {
                                frutn = NULL;
                        }

                        if (ses_create_generic(sdp, child->spt_senumnode,
                            pnode, frutn, phys_enum_type_list[i].pet_nodename,
                            phys_enum_type_list[i].pet_defaultlabel, &tn) != 0)
                                return (-1);

                        child->spt_tnode = tn;
                        /*
                         * For some SES element there may be protocol specific
                         * information to process.   Here we are processing
                         * the association between enclosure controller and
                         * SAS expanders.
                         */
                        if (phys_enum_type_list[i].pet_type ==
                            SES_ET_ESC_ELECTRONICS) {
                                /* create SAS expander node */
                                if (ses_create_protocol_specific(sdp,
                                    child->spt_senumnode, tn,
                                    phys_enum_type_list[i].pet_type,
                                    cp, phys_enum_type_list[i].pet_dorange) !=
                                    0) {
                                        return (-1);
                                }
                        }
                } else {
                        continue;
                }
                ret_ch = ses_enumerate_node(sdp, tn, cp, child, mrange);
                if (ret_ch)
                        ret = ret_ch; /* there was an error and set the ret. */
        }

        return (ret);
}

/*
 * Instantiate types of nodes that are specified in the hierarchy
 * element type list.
 */
static int
ses_create_children_from_phys_tree(ses_enum_data_t *sdp, tnode_t *pnode,
    ses_enum_chassis_t *cp, ses_phys_tree_t *phys_tree)
{
        topo_mod_t *mod = sdp->sed_mod;
        int mrange[N_PHYS_ENUM_TYPES] = { 0 };
        ses_enum_node_t *snp;
        int i, ret;

        /*
         * First get max range for each type of element to be enumerated.
         */
        for (i = 0; i < N_PHYS_ENUM_TYPES; i++) {
                if (phys_enum_type_list[i].pet_dorange) {
                        for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
                            snp = topo_list_next(snp)) {
                                if (snp->sen_type ==
                                    phys_enum_type_list[i].pet_type) {
                                        if (snp->sen_instance > mrange[i])
                                                mrange[i] =
                                                    snp->sen_instance;
                                }
                        }
                }
        }

        topo_mod_dprintf(mod, "%s: creating nodes from FRU hierarchy tree.",
            cp->sec_csn);

        if ((ret = ses_enumerate_node(sdp, pnode, cp, phys_tree, mrange)) !=
            0) {
                topo_mod_dprintf(mod,
                    "ses_create_children_from_phys_tree() failed: ");
                return (ret);
        }

        return (0);
}

/*
 * Instantiate a new chassis instance in the topology.
 */
static int
ses_create_chassis(ses_enum_data_t *sdp, tnode_t *pnode, ses_enum_chassis_t *cp)
{
        topo_mod_t *mod = sdp->sed_mod;
        nvlist_t *props;
        char *raw_manufacturer, *raw_model, *raw_revision;
        char *manufacturer = NULL, *model = NULL, *product = NULL;
        char *revision = NULL;
        char *serial;
        char **paths;
        size_t prodlen;
        tnode_t *tn;
        nvlist_t *fmri = NULL, *auth = NULL;
        int ret = -1;
        ses_enum_node_t *snp;
        ses_enum_target_t *stp;
        ses_enum_chassis_t *scp;
        int i, err;
        uint64_t sc_count = 0, pindex;
        ses_phys_tree_t *sproot = NULL;
        hrtime_t start;
        hrtime_t end;
        double duration;

        /*
         * Ignore any internal enclosures.
         */
        if (cp->sec_internal)
                return (0);

        /*
         * Check to see if there are any devices presennt in the chassis.  If
         * not, ignore the chassis alltogether.  This is most useful for
         * ignoring internal HBAs that present a SES target but don't actually
         * manage any of the devices.
         */
        for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
            snp = topo_list_next(snp)) {
                if (snp->sen_type == SES_ET_DEVICE ||
                    snp->sen_type == SES_ET_ARRAY_DEVICE)
                        break;
        }

        if (snp == NULL)
                return (0);

        props = ses_node_props(cp->sec_enclosure);

        /*
         * We use the following property mappings:
         *
         * manufacturer         vendor-id
         * model                product-id
         * serial-number        libses-chassis-serial
         */
        verify(nvlist_lookup_string(props, SES_EN_PROP_VID,
            &raw_manufacturer) == 0);
        verify(nvlist_lookup_string(props, SES_EN_PROP_PID, &raw_model) == 0);
        verify(nvlist_lookup_string(props, SES_EN_PROP_REV,
            &raw_revision) == 0);
        verify(nvlist_lookup_string(props, LIBSES_EN_PROP_CSN, &serial) == 0);

        /*
         * To construct the authority information, we 'clean' each string by
         * removing any offensive characters and trimmming whitespace.  For the
         * 'product-id', we use a concatenation of 'manufacturer-model'.  We
         * also take the numerical serial number and convert it to a string.
         */
        if ((manufacturer = topo_mod_clean_str(mod, raw_manufacturer)) ==
            NULL || (model = topo_mod_clean_str(mod, raw_model)) == NULL ||
            (revision = topo_mod_clean_str(mod, raw_revision)) == NULL) {
                goto error;
        }

        prodlen = strlen(manufacturer) + strlen(model) + 2;
        if ((product = topo_mod_alloc(mod, prodlen)) == NULL)
                goto error;

        (void) snprintf(product, prodlen, "%s-%s", manufacturer, model);

        /*
         * Construct the topo node and bind it to our parent.
         */
        if (topo_mod_nvalloc(mod, &auth, NV_UNIQUE_NAME) != 0)
                goto error;

        if (nvlist_add_string(auth, FM_FMRI_AUTH_PRODUCT, product) != 0 ||
            nvlist_add_string(auth, FM_FMRI_AUTH_CHASSIS, serial) != 0) {
                (void) topo_mod_seterrno(mod, EMOD_NVL_INVAL);
                goto error;
        }

        /*
         * We pass NULL for the parent FMRI because there is no resource
         * associated with it.  For the toplevel enclosure, we leave the
         * serial/part/revision portions empty, which are reserved for
         * individual components within the chassis.
         */
        if ((fmri = topo_mod_hcfmri(mod, NULL, FM_HC_SCHEME_VERSION,
            SES_ENCLOSURE, cp->sec_instance, NULL, auth,
            model, revision, serial)) == NULL) {
                topo_mod_dprintf(mod, "topo_mod_hcfmri() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        if ((tn = topo_node_bind(mod, pnode, SES_ENCLOSURE,
            cp->sec_instance, fmri)) == NULL) {
                topo_mod_dprintf(mod, "topo_node_bind() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        if (topo_method_register(mod, tn, ses_enclosure_methods) != 0) {
                topo_mod_dprintf(mod,
                    "topo_method_register() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        if (ses_set_standard_props(mod, NULL, tn, auth,
            ses_node_id(cp->sec_enclosure), cp->sec_target->set_devpath) != 0)
                goto error;

        /*
         * For enclosures, we want to include all possible targets (for upgrade
         * purposes).
         */
        for (i = 0, stp = topo_list_next(&cp->sec_targets); stp != NULL;
            stp = topo_list_next(stp), i++)
                ;

        verify(i != 0);
        paths = alloca(i * sizeof (char *));

        for (i = 0, stp = topo_list_next(&cp->sec_targets); stp != NULL;
            stp = topo_list_next(stp), i++)
                paths[i] = stp->set_devpath;


        if (topo_prop_set_string_array(tn, TOPO_PGROUP_SES,
            TOPO_PROP_PATHS, TOPO_PROP_IMMUTABLE, (const char **)paths,
            i, &err) != 0) {
                topo_mod_dprintf(mod,
                    "failed to create property %s: %s\n",
                    TOPO_PROP_PATHS, topo_strerror(err));
                goto error;
        }

        if (nvlist_lookup_uint64(props,
            LIBSES_PROP_PHYS_PARENT, &pindex) == 0) {
                start = gethrtime(); /* to mearusre performance */
                /*
                 * The enclosure is supported through SUNW,FRUID.
                 * Need to enumerate the nodes through hierarchical order.
                 */
                if ((sproot = topo_mod_zalloc(mod,
                    sizeof (ses_phys_tree_t))) == NULL) {
                        topo_mod_dprintf(mod,
                            "failed to allocate root: %s\n",
                            topo_strerror(err));
                        goto error;
                }
                sproot->spt_pindex = pindex;
                if (nvlist_lookup_boolean_value(props,
                    LIBSES_PROP_FRU, &sproot->spt_isfru) != 0) {
                        topo_mod_dprintf(mod,
                            "ses_create_chassis(): Failed to find prop %s "
                            "on enclosure element (CSN %s).",
                            LIBSES_PROP_FRU, cp->sec_csn);
                        /* an enclosure should be a FRU. continue to process. */
                        sproot->spt_isfru = B_TRUE;
                }
                if (nvlist_lookup_uint64(props,
                    SES_PROP_ELEMENT_ONLY_INDEX,
                    &sproot->spt_eonlyindex) != 0) {
                        topo_mod_dprintf(mod,
                            "ses_create_chassis(): Failed to find prop %s "
                            "on enclosure element (CSN %s).",
                            LIBSES_PROP_PHYS_PARENT, cp->sec_csn);
                        topo_mod_free(mod, sproot, sizeof (ses_phys_tree_t));
                        goto error;
                }
                if (sproot->spt_pindex != sproot->spt_eonlyindex) {
                        topo_mod_dprintf(mod, "ses_create_chassis(): "
                            "Enclosure element(CSN %s) should have "
                            "itself as the parent to be the root node "
                            "of FRU hierarchical tree.)", cp->sec_csn);
                        topo_mod_free(mod, sproot, sizeof (ses_phys_tree_t));
                        goto error;
                } else {
                        sproot->spt_snode = cp->sec_enclosure;
                        sproot->spt_tnode = tn;
                        /* construct a tree. */
                        if (ses_construct_phys_tree(sdp, cp, sproot) != 0) {
                                topo_mod_dprintf(mod, "ses_create_chassis(): "
                                    "Failed to construct FRU hierarchical "
                                    "tree on enclosure (CSN %s.)",
                                    cp->sec_csn);
                        }

                        /* enumerate elements from the tree. */
                        if (ses_create_children_from_phys_tree(sdp, tn, cp,
                            sproot) != 0) {
                                topo_mod_dprintf(mod, "ses_create_chassis(): "
                                    "Failed to create children topo nodes out "
                                    "of FRU hierarchical tree on enclosure "
                                    "(CSN %s).", cp->sec_csn);
                        }
                        /* destroy the phys tree. */
                        ses_phys_tree_free(mod, sproot);
                }

                end = gethrtime();
                duration = end - start;
                duration /= HR_SECOND;
                topo_mod_dprintf(mod,
                    "FRU boundary tree based enumeration: %.6f seconds",
                    duration);
        } else {
                /*
                 * Create the nodes for power supplies, fans, controllers and
                 * devices.  Note that SAS exopander nodes and connector nodes
                 * are handled through protocol specific processing of
                 * controllers.
                 */
                if (ses_create_children(sdp, tn, SES_ET_POWER_SUPPLY,
                    PSU, "PSU", cp, B_TRUE) != 0 ||
                    ses_create_children(sdp, tn, SES_ET_COOLING,
                    FAN, "FAN", cp, B_TRUE) != 0 ||
                    ses_create_children(sdp, tn, SES_ET_ESC_ELECTRONICS,
                    CONTROLLER, "CONTROLLER", cp, B_TRUE) != 0 ||
                    ses_create_children(sdp, tn, SES_ET_DEVICE,
                    BAY, "BAY", cp, B_TRUE) != 0 ||
                    ses_create_children(sdp, tn, SES_ET_ARRAY_DEVICE,
                    BAY, "BAY", cp, B_TRUE) != 0)
                        goto error;
        }

        if (cp->sec_maxinstance != SES_INST_NOTSET &&
            (topo_node_range_create(mod, tn, SUBCHASSIS, 0,
            cp->sec_maxinstance) != 0)) {
                topo_mod_dprintf(mod, "topo_node_create_range() failed: %s",
                    topo_mod_errmsg(mod));
                goto error;
        }

        for (scp = topo_list_next(&cp->sec_subchassis); scp != NULL;
            scp = topo_list_next(scp)) {

                if (ses_create_subchassis(sdp, tn, scp) != 0)
                        goto error;

                topo_mod_dprintf(mod, "created Subchassis node with "
                    "instance %" PRIu64 "\nand target (%s) under Chassis "
                    "with CSN %s", scp->sec_instance,
                    scp->sec_target->set_devpath, cp->sec_csn);

                sc_count++;
        }

        topo_mod_dprintf(mod, "%s: created %" PRIu64 " %s nodes",
            cp->sec_csn, sc_count, SUBCHASSIS);

        cp->sec_target->set_refcount++;
        topo_node_setspecific(tn, cp->sec_target);

        ret = 0;
error:
        topo_mod_strfree(mod, manufacturer);
        topo_mod_strfree(mod, model);
        topo_mod_strfree(mod, revision);
        topo_mod_strfree(mod, product);

        nvlist_free(fmri);
        nvlist_free(auth);
        return (ret);
}

/*
 * Create a bay node explicitly enumerated via XML.
 */
static int
ses_create_bays(ses_enum_data_t *sdp, tnode_t *pnode)
{
        topo_mod_t *mod = sdp->sed_mod;
        ses_enum_chassis_t *cp;

        /*
         * Iterate over chassis looking for an internal enclosure.  This
         * property is set via a vendor-specific plugin, and there should only
         * ever be a single internal chassis in a system.
         */
        for (cp = topo_list_next(&sdp->sed_chassis); cp != NULL;
            cp = topo_list_next(cp)) {
                if (cp->sec_internal)
                        break;
        }

        if (cp == NULL) {
                topo_mod_dprintf(mod, "failed to find internal chassis\n");
                return (-1);
        }

        if (ses_create_children(sdp, pnode, SES_ET_DEVICE,
            BAY, "BAY", cp, B_FALSE) != 0 ||
            ses_create_children(sdp, pnode, SES_ET_ARRAY_DEVICE,
            BAY, "BAY", cp, B_FALSE) != 0)
                return (-1);

        return (0);
}

/*
 * Initialize chassis or subchassis.
 */
static int
ses_init_chassis(topo_mod_t *mod, ses_enum_data_t *sdp, ses_enum_chassis_t *pcp,
    ses_enum_chassis_t *cp, ses_node_t *np, nvlist_t *props,
    uint64_t subchassis, ses_chassis_type_e flags)
{
        boolean_t internal, ident;

        assert((flags & (SES_NEW_CHASSIS | SES_NEW_SUBCHASSIS |
            SES_DUP_CHASSIS | SES_DUP_SUBCHASSIS)) != 0);

        assert(cp != NULL);
        assert(np != NULL);
        assert(props != NULL);

        if (flags & (SES_NEW_SUBCHASSIS | SES_DUP_SUBCHASSIS))
                assert(pcp != NULL);

        topo_mod_dprintf(mod, "ses_init_chassis: %s: index %" PRIu64
            ", flags (%d)", sdp->sed_name, subchassis, flags);

        if (flags & (SES_NEW_CHASSIS | SES_NEW_SUBCHASSIS)) {

                topo_mod_dprintf(mod, "new chassis/subchassis");
                if (nvlist_lookup_boolean_value(props,
                    LIBSES_EN_PROP_INTERNAL, &internal) == 0)
                        cp->sec_internal = internal;

                cp->sec_enclosure = np;
                cp->sec_target = sdp->sed_target;

                if (flags & SES_NEW_CHASSIS) {
                        if (!cp->sec_internal)
                                cp->sec_instance = sdp->sed_instance++;
                        topo_list_append(&sdp->sed_chassis, cp);
                } else {
                        if (subchassis != NO_SUBCHASSIS)
                                cp->sec_instance = subchassis;
                        else
                                cp->sec_instance = pcp->sec_scinstance++;

                        if (cp->sec_instance > pcp->sec_maxinstance)
                                pcp->sec_maxinstance = cp->sec_instance;

                        topo_list_append(&pcp->sec_subchassis, cp);
                }

        } else {
                topo_mod_dprintf(mod, "dup chassis/subchassis");
                if (nvlist_lookup_boolean_value(props,
                    SES_PROP_IDENT, &ident) == 0) {
                        topo_mod_dprintf(mod,  "overriding enclosure node");

                        cp->sec_enclosure = np;
                        cp->sec_target = sdp->sed_target;
                }
        }

        topo_list_append(&cp->sec_targets, sdp->sed_target);
        sdp->sed_current = cp;

        return (0);
}

/*
 * Gather nodes from the current SES target into our chassis list, merging the
 * results if necessary.
 */
static ses_walk_action_t
ses_enum_gather(ses_node_t *np, void *data)
{
        nvlist_t *props = ses_node_props(np);
        ses_enum_data_t *sdp = data;
        topo_mod_t *mod = sdp->sed_mod;
        ses_enum_chassis_t *cp, *scp;
        ses_enum_node_t *snp;
        ses_alt_node_t *sap;
        char *csn;
        uint64_t instance, type;
        uint64_t prevstatus, status;
        boolean_t report;
        uint64_t subchassis = NO_SUBCHASSIS;

        if (ses_node_type(np) == SES_NODE_ENCLOSURE) {
                /*
                 * If we have already identified the chassis for this target,
                 * then this is a secondary enclosure and we should ignore it,
                 * along with the rest of the tree (since this is depth-first).
                 */
                if (sdp->sed_current != NULL)
                        return (SES_WALK_ACTION_TERMINATE);

                /*
                 * Go through the list of chassis we have seen so far and see
                 * if this serial number matches one of the known values.
                 * If so, check whether this enclosure is a subchassis.
                 */
                if (nvlist_lookup_string(props, LIBSES_EN_PROP_CSN,
                    &csn) != 0)
                        return (SES_WALK_ACTION_TERMINATE);

                (void) nvlist_lookup_uint64(props, LIBSES_EN_PROP_SUBCHASSIS_ID,
                    &subchassis);

                topo_mod_dprintf(mod, "ses_enum_gather: Enclosure Node (%s) "
                    "CSN (%s), subchassis (%" PRIu64 ")", sdp->sed_name, csn,
                    subchassis);

                /*
                 * We need to determine whether this enclosure node
                 * represents a chassis or a subchassis. Since we may
                 * receive the enclosure nodes in a non-deterministic
                 * manner, we need to account for all possible combinations:
                 *      1. Chassis for the current CSN has not yet been
                 *         allocated
                 *              1.1 This is a new chassis:
                 *                      allocate and instantiate the chassis
                 *              1.2 This is a new subchassis:
                 *                      allocate a placeholder chassis
                 *                      allocate and instantiate the subchassis
                 *                      link the subchassis to the chassis
                 *      2. Chassis for the current CSN has been allocated
                 *              2.1 This is a duplicate chassis enclosure
                 *                      check whether to override old chassis
                 *                      append to chassis' target list
                 *              2.2 Only placeholder chassis exists
                 *                      fill in the chassis fields
                 *              2.3 This is a new subchassis
                 *                      allocate and instantiate the subchassis
                 *                      link the subchassis to the chassis
                 *              2.4 This is a duplicate subchassis enclosure
                 *                       check whether to override old chassis
                 *                       append to chassis' target list
                 */

                for (cp = topo_list_next(&sdp->sed_chassis); cp != NULL;
                    cp = topo_list_next(cp))
                        if (strcmp(cp->sec_csn, csn) == 0)
                                break;

                if (cp == NULL) {
                        /* 1. Haven't seen a chassis with this CSN before */

                        if ((cp = topo_mod_zalloc(mod,
                            sizeof (ses_enum_chassis_t))) == NULL)
                                goto error;

                        cp->sec_scinstance = SES_STARTING_SUBCHASSIS;
                        cp->sec_maxinstance = SES_INST_NOTSET;
                        cp->sec_csn = csn;

                        if (subchassis == NO_SUBCHASSIS) {
                                /* 1.1 This is a new chassis */

                                topo_mod_dprintf(mod, "%s: Initialize new "
                                    "chassis with CSN %s", sdp->sed_name, csn);

                                if (ses_init_chassis(mod, sdp, NULL, cp,
                                    np, props, NO_SUBCHASSIS,
                                    SES_NEW_CHASSIS) < 0)
                                        goto error;
                        } else {
                                /* 1.2 This is a new subchassis */

                                topo_mod_dprintf(mod, "%s: Initialize new "
                                    "subchassis with CSN %s and index %" PRIu64,
                                    sdp->sed_name, csn, subchassis);

                                if ((scp = topo_mod_zalloc(mod,
                                    sizeof (ses_enum_chassis_t))) == NULL)
                                        goto error;

                                scp->sec_csn = csn;

                                if (ses_init_chassis(mod, sdp, cp, scp, np,
                                    props, subchassis, SES_NEW_SUBCHASSIS) < 0)
                                        goto error;
                        }
                } else {
                        /*
                         * We have a chassis or subchassis with this CSN.  If
                         * it's a chassis, we must check to see whether it is
                         * a placeholder previously created because we found a
                         * subchassis with this CSN.  We will know that because
                         * the sec_target value will not be set; it is set only
                         * in ses_init_chassis().  In that case, initialise it
                         * as a new chassis; otherwise, it's a duplicate and we
                         * need to append only.
                         */
                        if (subchassis == NO_SUBCHASSIS) {
                                if (cp->sec_target != NULL) {
                                        /* 2.1 This is a duplicate chassis */

                                        topo_mod_dprintf(mod, "%s: Append "
                                            "duplicate chassis with CSN (%s)",
                                            sdp->sed_name, csn);

                                        if (ses_init_chassis(mod, sdp, NULL, cp,
                                            np, props, NO_SUBCHASSIS,
                                            SES_DUP_CHASSIS) < 0)
                                                goto error;
                                } else {
                                        /* Placeholder chassis - init it up */
                                        topo_mod_dprintf(mod, "%s: Initialize"
                                            "placeholder chassis with CSN %s",
                                            sdp->sed_name, csn);

                                        if (ses_init_chassis(mod, sdp, NULL,
                                            cp, np, props, NO_SUBCHASSIS,
                                            SES_NEW_CHASSIS) < 0)
                                                goto error;

                                }
                        } else {
                                /* This is a subchassis */

                                for (scp = topo_list_next(&cp->sec_subchassis);
                                    scp != NULL; scp = topo_list_next(scp))
                                        if (scp->sec_instance == subchassis)
                                                break;

                                if (scp == NULL) {
                                        /* 2.3 This is a new subchassis */

                                        topo_mod_dprintf(mod, "%s: Initialize "
                                            "new subchassis with CSN (%s)",
                                            sdp->sed_name, csn);

                                        if ((scp = topo_mod_zalloc(mod,
                                            sizeof (ses_enum_chassis_t)))
                                            == NULL)
                                                goto error;

                                        scp->sec_csn = csn;

                                        if (ses_init_chassis(mod, sdp, cp, scp,
                                            np, props, subchassis,
                                            SES_NEW_SUBCHASSIS) < 0)
                                                goto error;
                                } else {
                                        /* 2.4 This is a duplicate subchassis */

                                        topo_mod_dprintf(mod, "%s: Append "
                                            "duplicate subchassis with "
                                            "CSN (%s)", sdp->sed_name, csn);

                                        if (ses_init_chassis(mod, sdp, cp, scp,
                                            np, props, subchassis,
                                            SES_DUP_SUBCHASSIS) < 0)
                                                goto error;
                                }
                        }
                }
        } else if (ses_node_type(np) == SES_NODE_ELEMENT) {
                /*
                 * If we haven't yet seen an enclosure node and identified the
                 * current chassis, something is very wrong; bail out.
                 */
                if (sdp->sed_current == NULL)
                        return (SES_WALK_ACTION_TERMINATE);

                /*
                 * If this isn't one of the element types we care about, then
                 * ignore it.
                 */
                verify(nvlist_lookup_uint64(props, SES_PROP_ELEMENT_TYPE,
                    &type) == 0);
                if (type != SES_ET_DEVICE &&
                    type != SES_ET_ARRAY_DEVICE &&
                    type != SES_ET_SUNW_FANBOARD &&
                    type != SES_ET_SUNW_FANMODULE &&
                    type != SES_ET_COOLING &&
                    type != SES_ET_SUNW_POWERBOARD &&
                    type != SES_ET_SUNW_POWERMODULE &&
                    type != SES_ET_POWER_SUPPLY &&
                    type != SES_ET_ESC_ELECTRONICS &&
                    type != SES_ET_SAS_EXPANDER &&
                    type != SES_ET_SAS_CONNECTOR)
                        return (SES_WALK_ACTION_CONTINUE);

                /*
                 * Get the current instance number and see if we already know
                 * about this element.  If so, it means we have multiple paths
                 * to the same elements, and we should ignore the current path.
                 */
                verify(nvlist_lookup_uint64(props, SES_PROP_ELEMENT_CLASS_INDEX,
                    &instance) == 0);
                if (type == SES_ET_DEVICE || type == SES_ET_ARRAY_DEVICE)
                        (void) nvlist_lookup_uint64(props, SES_PROP_BAY_NUMBER,
                            &instance);

                cp = sdp->sed_current;

                for (snp = topo_list_next(&cp->sec_nodes); snp != NULL;
                    snp = topo_list_next(snp)) {
                        if (snp->sen_type == type &&
                            snp->sen_instance == instance)
                                break;
                }

                /*
                 * We prefer the new element under the following circumstances:
                 *
                 * - The currently known element's status is unknown or not
                 *   available, but the new element has a known status.  This
                 *   occurs if a given element is only available through a
                 *   particular target.
                 *
                 * - This is an ESC_ELECTRONICS element, and the 'reported-via'
                 *   property is set.  This allows us to get reliable firmware
                 *   revision information from the enclosure node.
                 */
                if (snp != NULL) {
                        if (nvlist_lookup_uint64(
                            ses_node_props(snp->sen_node),
                            SES_PROP_STATUS_CODE, &prevstatus) != 0)
                                prevstatus = SES_ESC_UNSUPPORTED;
                        if (nvlist_lookup_uint64(
                            props, SES_PROP_STATUS_CODE, &status) != 0)
                                status = SES_ESC_UNSUPPORTED;
                        if (nvlist_lookup_boolean_value(
                            props, SES_PROP_REPORT, &report) != 0)
                                report = B_FALSE;

                        if ((SES_STATUS_UNAVAIL(prevstatus) &&
                            !SES_STATUS_UNAVAIL(status)) ||
                            (type == SES_ET_ESC_ELECTRONICS &&
                            report)) {
                                snp->sen_node = np;
                                snp->sen_target = sdp->sed_target;
                        }

                        if ((sap = topo_mod_zalloc(mod,
                            sizeof (ses_alt_node_t))) == NULL)
                                goto error;

                        sap->san_node = np;
                        topo_list_append(&snp->sen_alt_nodes, sap);

                        return (SES_WALK_ACTION_CONTINUE);
                }

                if ((snp = topo_mod_zalloc(mod,
                    sizeof (ses_enum_node_t))) == NULL)
                        goto error;

                if ((sap = topo_mod_zalloc(mod,
                    sizeof (ses_alt_node_t))) == NULL) {
                        topo_mod_free(mod, snp, sizeof (ses_enum_node_t));
                        goto error;
                }

                topo_mod_dprintf(mod, "%s: adding node (%" PRIu64
                    ", %" PRIu64 ")", sdp->sed_name, type, instance);
                snp->sen_node = np;
                snp->sen_type = type;
                snp->sen_instance = instance;
                snp->sen_target = sdp->sed_target;
                sap->san_node = np;
                topo_list_append(&snp->sen_alt_nodes, sap);
                topo_list_append(&cp->sec_nodes, snp);

                if (type == SES_ET_DEVICE)
                        cp->sec_hasdev = B_TRUE;
        }

        return (SES_WALK_ACTION_CONTINUE);

error:
        sdp->sed_errno = -1;
        return (SES_WALK_ACTION_TERMINATE);
}

static int
ses_process_dir(const char *dirpath, ses_enum_data_t *sdp)
{
        topo_mod_t *mod = sdp->sed_mod;
        DIR *dir;
        struct dirent *dp;
        char path[PATH_MAX];
        ses_enum_target_t *stp;
        int err = -1;

        /*
         * Open the SES target directory and iterate over any available
         * targets.
         */
        if ((dir = opendir(dirpath)) == NULL) {
                /*
                 * If the SES target directory does not exist, then return as if
                 * there are no active targets.
                 */
                topo_mod_dprintf(mod, "failed to open ses "
                    "directory '%s'", dirpath);
                return (0);
        }

        while ((dp = readdir(dir)) != NULL) {
                if (strcmp(dp->d_name, ".") == 0 ||
                    strcmp(dp->d_name, "..") == 0)
                        continue;

                /*
                 * Create a new target instance and take a snapshot.
                 */
                if ((stp = topo_mod_zalloc(mod,
                    sizeof (ses_enum_target_t))) == NULL)
                        goto error;

                (void) pthread_mutex_init(&stp->set_lock, NULL);

                (void) snprintf(path, sizeof (path), "%s/%s", dirpath,
                    dp->d_name);

                /*
                 * We keep track of the SES device path and export it on a
                 * per-node basis to allow higher level software to get to the
                 * corresponding SES state.
                 */
                if ((stp->set_devpath = topo_mod_strdup(mod, path)) == NULL) {
                        topo_mod_free(mod, stp, sizeof (ses_enum_target_t));
                        goto error;
                }

                if ((stp->set_target =
                    ses_open(LIBSES_VERSION, path)) == NULL) {
                        topo_mod_dprintf(mod, "failed to open ses target "
                            "'%s': %s", dp->d_name, ses_errmsg());
                        ses_sof_alloc(mod, stp->set_devpath);
                        topo_mod_free(mod, stp, sizeof (ses_enum_target_t));
                        continue;
                }
                topo_mod_dprintf(mod, "open contract");
                ses_ssl_alloc(mod, stp);
                ses_create_contract(mod, stp);

                stp->set_refcount = 1;
                sdp->sed_target = stp;
                stp->set_snap = ses_snap_hold(stp->set_target);
                stp->set_snaptime = gethrtime();

                /*
                 * Enumerate over all SES elements and merge them into the
                 * correct ses_enum_chassis_t.
                 */
                sdp->sed_current = NULL;
                sdp->sed_errno = 0;
                sdp->sed_name = dp->d_name;
                (void) ses_walk(stp->set_snap, ses_enum_gather, sdp);

                if (sdp->sed_errno != 0)
                        goto error;
        }

        err = 0;
error:
        (void) closedir(dir);
        return (err);
}

/*
 * Different generations of SMCI's 4U36 storage servers used different models
 * of front and rear SAS expanders.
 */
#define SMCI4U36_FRONT_EXPANDER_PID1    "LSI-SAS2X36"
#define SMCI4U36_FRONT_EXPANDER_PID2    "LSI-SAS3x40"
#define SMCI4U36_FRONT_EXPANDER_PID3    "SMC-SC846P"

#define SMCI4U36_REAR_EXPANDER_PID1     "LSI-CORP-SAS2X28"
#define SMCI4U36_REAR_EXPANDER_PID2     "LSI-SAS3x28"

static int
smci_4u36_bay_label(topo_mod_t *mod, tnode_t *node, topo_version_t version,
    nvlist_t *in, nvlist_t **out)
{
        int err, ret = -1;
        nvlist_t *pargs, *auth, *nvl = NULL, *fmri;
        char *label = NULL, *product_id;

        /*
         * Now look for a private argument list to determine if the invoker is
         * trying to do a set operation and if so, return an error as this
         * method only supports get operations.
         */
        if ((nvlist_lookup_nvlist(in, TOPO_PROP_PARGS, &pargs) == 0) &&
            nvlist_exists(pargs, TOPO_PROP_VAL_VAL)) {
                topo_mod_dprintf(mod, "%s: set operation not suppported",
                    __func__);
                return (topo_mod_seterrno(mod, EMOD_NVL_INVAL));
        }

        if (topo_node_resource(node, &fmri, &err) != 0) {
                (void) topo_mod_seterrno(mod, err);
                goto err;
        }

        if (nvlist_lookup_nvlist(fmri, FM_FMRI_AUTHORITY, &auth) != 0 ||
            nvlist_lookup_string(auth, FM_FMRI_AUTH_PRODUCT, &product_id) !=
            0) {
                topo_mod_dprintf(mod, "%s: malformed FMRI", __func__);
                (void) topo_mod_seterrno(mod, EMOD_UNKNOWN);
                nvlist_free(fmri);
                goto err;
        }
        nvlist_free(fmri);

        if (strcmp(product_id, SMCI4U36_FRONT_EXPANDER_PID1) == 0 ||
            strcmp(product_id, SMCI4U36_FRONT_EXPANDER_PID2) == 0 ||
            strcmp(product_id, SMCI4U36_FRONT_EXPANDER_PID3) == 0) {
                err = asprintf(&label, "Front Slot %" PRIu64,
                    topo_node_instance(node));
        } else if (strcmp(product_id, SMCI4U36_REAR_EXPANDER_PID1) == 0 ||
            strcmp(product_id, SMCI4U36_REAR_EXPANDER_PID2) == 0) {
                err = asprintf(&label, "Rear Slot %" PRIu64,
                    topo_node_instance(node));
        } else {
                topo_mod_dprintf(mod, "%s: unexpected expander product id: %s",
                    __func__, product_id);
                (void) topo_mod_seterrno(mod, EMOD_UNKNOWN);
                goto err;
        }

        if (err < 0) {
                (void) topo_mod_seterrno(mod, EMOD_NOMEM);
                goto err;
        }

        if (topo_mod_nvalloc(mod, &nvl, NV_UNIQUE_NAME) != 0 ||
            nvlist_add_string(nvl, TOPO_PROP_VAL_NAME, TOPO_PROP_LABEL) != 0 ||
            nvlist_add_uint32(nvl, TOPO_PROP_VAL_TYPE, TOPO_TYPE_STRING)
            != 0 ||
            nvlist_add_string(nvl, TOPO_PROP_VAL_VAL, label)
            != 0) {
                topo_mod_dprintf(mod, "Failed to allocate 'out' nvlist");
                nvlist_free(nvl);
                (void) topo_mod_seterrno(mod, EMOD_NOMEM);
                goto err;
        }
        *out = nvl;
        ret = 0;
err:
        free(label);
        return (ret);

}

static void
ses_release(topo_mod_t *mod, tnode_t *tn)
{
        ses_enum_target_t *stp;

        if ((stp = topo_node_getspecific(tn)) != NULL) {
                topo_node_setspecific(tn, NULL);
                ses_target_free(mod, stp);
        }
}

/*ARGSUSED*/
static int
ses_enum(topo_mod_t *mod, tnode_t *rnode, const char *name,
    topo_instance_t min, topo_instance_t max, void *arg, void *notused)
{
        ses_enum_chassis_t *cp;
        ses_enum_data_t *data;

        /*
         * Check to make sure we're being invoked sensibly, and that we're not
         * being invoked as part of a post-processing step.
         */
        if (strcmp(name, SES_ENCLOSURE) != 0 && strcmp(name, BAY) != 0)
                return (0);

        /*
         * If this is the first time we've called our enumeration method, then
         * gather information about any available enclosures.
         */
        if ((data = topo_mod_getspecific(mod)) == NULL) {
                ses_sof_freeall(mod);
                if ((data = topo_mod_zalloc(mod, sizeof (ses_enum_data_t))) ==
                    NULL)
                        return (-1);

                data->sed_mod = mod;
                topo_mod_setspecific(mod, data);

                if (dev_list_gather(mod, &data->sed_devs) != 0)
                        goto error;

                /*
                 * We search both the ses(4D) and sgen(4D) locations, so we are
                 * independent of any particular driver class bindings.
                 */
                if (ses_process_dir("/dev/es", data) != 0 ||
                    ses_process_dir("/dev/scsi/ses", data) != 0)
                        goto error;
        }

        if (strcmp(name, SES_ENCLOSURE) == 0) {
                /*
                 * This is a request to enumerate external enclosures.  Go
                 * through all the targets and create chassis nodes where
                 * necessary.
                 */
                for (cp = topo_list_next(&data->sed_chassis); cp != NULL;
                    cp = topo_list_next(cp)) {
                        if (ses_create_chassis(data, rnode, cp) != 0)
                                goto error;
                }
        } else {
                /*
                 * This is a request to enumerate a specific bay underneath the
                 * root chassis (for internal disks).
                 */
                if (ses_create_bays(data, rnode) != 0)
                        goto error;
        }

        /*
         * This is a bit of a kludge.  In order to allow internal disks to be
         * enumerated and share snapshot-specific information with the external
         * enclosure enumeration, we rely on the fact that we will be invoked
         * for the 'ses-enclosure' node last.
         */
        if (strcmp(name, SES_ENCLOSURE) == 0) {
                for (cp = topo_list_next(&data->sed_chassis); cp != NULL;
                    cp = topo_list_next(cp))
                        ses_data_free(data, cp);
                ses_data_free(data, NULL);
                topo_mod_setspecific(mod, NULL);
        }
        return (0);

error:
        for (cp = topo_list_next(&data->sed_chassis); cp != NULL;
            cp = topo_list_next(cp))
                ses_data_free(data, cp);
        ses_data_free(data, NULL);
        topo_mod_setspecific(mod, NULL);
        return (-1);
}

static const topo_modops_t ses_ops =
        { ses_enum, ses_release };

static topo_modinfo_t ses_info =
        { SES_ENCLOSURE, FM_FMRI_SCHEME_HC, SES_VERSION, &ses_ops };

/*ARGSUSED*/
int
_topo_init(topo_mod_t *mod, topo_version_t version)
{
        int rval;

        if (getenv("TOPOSESDEBUG") != NULL)
                topo_mod_setdebug(mod);

        topo_mod_dprintf(mod, "initializing %s enumerator\n",
            SES_ENCLOSURE);

        if ((rval = topo_mod_register(mod, &ses_info, TOPO_VERSION)) == 0)
                ses_thread_init(mod);

        return (rval);
}

void
_topo_fini(topo_mod_t *mod)
{
        ses_thread_fini(mod);
        ses_sof_freeall(mod);
        topo_mod_unregister(mod);
}